Formulation and method for preparation of organic electronic devices

Abstract

The present invention relates to novel formulations comprising an organic semiconductor (OSC) and one or more organic solvents. The formulation comprises a viscosity at 25 C. of less than 15 mPas and the boiling point of the solvent is at most 400 C. Furthermore, the present invention describes the use of these formulations as inks for the preparation of organic electronic (OE) devices, especially organic photovoltaic (OPV) cells and OLED devices, to methods for preparing OE devices using the novel formulations, and to OE devices, OLED devices and OPV cells prepared from such methods and formulations.

Claims

1. Process of preparing an organic electronic (OE) device, comprising the steps of a) depositing a formulation comprising one or more organic semiconducting compounds (OSC) and one or more organic solvents, wherein said formulation has a viscosity at 25 C. in the range of 1 to 9 mPas and wherein the boiling point of the solvent is at most 400 C., onto a substrate to form a film or layer; and b) removing the solvent(s); wherein the one or more organic semiconducting compounds comprises a repeating unit of formula P-6: ##STR00192## wherein n is an integer >1, R on each occurrence identically or differently denotes H, F, Cl, Br, I, CN, a straight-chain, branched or cyclic alkyl group having from 1 to 40 C atoms, in which one of more C atoms are optionally replaced by O, S, O-C, CO-O, O-CO-O, CR.sup.O=CR.sup.O or CC such that O- and/or S- atoms are not linked directly to each other, and in which one or more H atoms are optionally replaced by F, Cl, Br, I or CN, or denotes an aryl or heteroaryl group having from 4 to 20 ring atoms that is unsubstituted or substituted by one or more non-aromatic groups R.sup.S, and wherein one or more groups R may also form a mono or polycyclic aliphatic or aromatic ring system with one another and/or with the ring to which they are attached, R.sup.Son each occurrence identically or differently denotes F, Cl, Br, I, CN,) Sn(R.sup.OO).sub.3, Si(R.sup.OO).sub.3, or B(R.sup.OO).sub.2 a straight-chain, branched or cyclic alkyl group having from 1 to 25 C atoms, in which one of more C atoms are optionally replaced by 0, S, O-C, CO-O, O-OO-O, CR.sup.O=CR.sup.O or CC such that O- and/or S- atoms are not linked directly to each other, and in which one or more H atoms are optionally replaced by F, Cl, Br, I or CN, or RS denotes an aryl or heteroaryl group having from 4 to 20 ring atoms that is unsubstituted or substituted by one or more non-aromatic groups R.sup.S, and optionally wherein one or more groups R.sup.S form a mono or polycyclic aliphatic or aromatic ring system with one another and/or with R, R.sup.O on each occurrence identically or differently denotes H, F, Cl, CN, alkyl having from 1 to 12 C atoms or aryl or heteroaryl having from 4 to 10 ring atoms, and R.sup.OO on each occurrence identically or differently denotes H or an aliphatic or aromatic hydrocarbon group having from 1 to 20 C atoms, wherein two groups R.sup.OO may also form a ring together with the hetero atom to which they are attached, and wherein the formulation is applied by gravure printing or flexographic printing.

2. Process according to claim 1, wherein the formulation is applied with a printing device and the cell etch of the printing device is in the range of 4 cm.sup.3/m.sup.2 to 18 cm.sup.3/m.sup.2.

3. Process according to claim 1, wherein the print speed is 100 m/minute or less.

4. Process according to claim 1, wherein the surface on which the formulation is applied comprises a surface energy in the range of 25 to 130 mN m.sup.1.

5. Process according to claim 1, wherein the evaporation of the solvent is achieved below the boiling point of the solvent.

6. Process according to claim 1, wherein said formulation is a solution.

7. Process according to claim 1, wherein said formulation has a surface tension in the range of 22 mN/m to 50 mN/m.

8. Process according to claim 1, wherein said organic solvent comprises Hansen Solubility parameters of H.sub.d in the range of 17.0 to 23.2 MPa.sup.0.5, H.sub.p in the range of 0.2 to 12.5 MPa.sup.0.5 and H.sub.h in the range of 0.0 to 20.0 MPa.sup.0.5.

9. Process according to claim 1, wherein said organic solvent comprises Hansen Solubility parameters of H.sub.d in the range of 17.0 to 23.2 MPa.sup.0.5, H.sub.p in the range of 0.2 to 10.5 MPa.sup.0.5 and H.sub.h in the range of 0.0 to 5.0 MPa.sup.0.5.

10. Process according to claim 8, wherein said organic solvent comprises one or more of an aromatic and/or heteroaromatic compound.

11. Process according to claim 10, wherein said organic solvent comprises one or more aromatic hydrocarbon compounds.

12. Process according to claim 11, wherein said aromatic hydrocarbon compound comprises a cycloalkyl group.

13. Process according to claim 11, wherein said aromatic hydrocarbon compound comprises an alkyl group having 1 to 8 carbon atoms.

14. Process according to claim 1, wherein said one or more organic solvents is a mixture of hydrocarbon aromatic compounds.

15. Process according to claim 1, wherein said organic solvent has a boiling point of at least 130 C.

16. Process according to claim 1, wherein said one or more organic solvents is a mixture of compounds having different boiling points and the boiling point of the compound with the lowest boiling point is at least 10 C. below the boiling point of the compound with the highest boiling point.

17. Process according to claim 1, wherein said one or more organic solvents is a mixture of compounds having different boiling points and the boiling point of the compound with the lowest boiling point is at most 100 C. below the boiling point of the compound with the highest boiling point.

18. Process according to claim 1, wherein said formulation comprises at least 80% by weight of said organic solvents.

19. Process according to claim 1, wherein said solvent has a partition ratio log P of at least 1.5.

20. Process according to claim 1, wherein said formulation comprises at least one inert binder.

21. Process according to claim 20, wherein said inert binder is a polymer comprising repeating units derived from styrene monomers and/or olefins.

22. Process according to claim 20, wherein said inert binder is a polymer comprising at least 80% by weight of repeating units derived from styrene monomers and/or olefins.

23. Process according to claim 20, wherein said inert binder is a polymer having a weight average molecular weight of at least 200,000 g/mol.

24. Process according to claim 1, wherein the organic semiconducting compound is an organic light emitting material and/or charge transporting material.

25. Process according to claim 1, wherein the organic semiconducting compound has a molecular weight of 5000 g/mol or less.

26. Process according to claim 1, wherein the formulation comprises a host material.

27. Process according to claim 1, wherein the formulation comprises 0.1 to 5% by weight organic semiconducting compounds.

28. Process according to claim 20, wherein the weight ratio of said semiconducting compound to said inert binder is in the range of 5:1 to 1:1.

29. Process according to claim 1, wherein the formulation comprises at least one wetting agent.

30. Process according to claim 29, wherein the wetting agent is volatile and is not capable of chemically reacting with said semiconducting compound.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1A exemplarily and schematically depicts a typical bottom gate (BG), top contact (TC) OFET device according to the present invention.

(2) FIG. 1B exemplarily and schematically depicts a typical bottom gate (BG), bottom contact (BC) OFET device according to the present invention.

(3) FIG. 2 exemplarily and schematically depicts a top gate (TG) OFET device according to the present invention.

(4) FIG. 3 exemplarily and schematically depicts a typical OPV device according to the present invention.

(5) FIG. 4 exemplarily and schematically depicts a preferred OPV device according to the present invention.

(6) FIG. 5 shows the results of transfer and stress measurements of an embodiment of an OFET device according to the invention.

(7) FIG. 6 shows the results of transfer and stress measurements of another embodiment of an OFET device according to the invention.

(8) FIG. 7 shows the results of transfer and stress measurements of an embodiment of an OFET device according to the invention.

(9) FIG. 8 shows the results of transfer and stress measurements of another embodiment of an OFET device according to the invention.

(10) FIG. 9 shows the results of transfer and stress measurements of an embodiment of an OFET device according to the invention.

(11) FIG. 10 shows the results of transfer and stress measurements of another embodiment of an OFET device according to the invention.

(12) FIG. 11 shows the results of transfer and stress measurements of an embodiment of an OFET device according to the invention.

(13) FIG. 12 shows the results of transfer and stress measurements of another embodiment of an OFET device according to the invention.

(14) FIG. 13 shows the results of transfer and stress measurements of an embodiment of an OFET device according to the invention.

(15) FIG. 14 shows the results of transfer and stress measurements of another embodiment of an OFET device according to the invention.

(16) FIG. 15a shows the results of the transfer characteristic measurement of an embodiment of an OFET device according to the invention.

(17) FIG. 15b shows the results of the linear and saturation mobility of this same embodiment of an OFET device according to the invention.

(18) FIG. 16 shows the results of transfer and stress measurements of another embodiment of an OFET device according to the invention.

(19) FIG. 17a shows the results of the transfer characteristic measurement of an embodiment of an OFET device according to the invention.

(20) FIG. 17b shows the results of the linear and saturation mobility of this same embodiment of an OFET device according to the invention.

(21) FIG. 18 shows the results of transfer and stress measurements of another embodiment of an OFET device according to the invention.

(22) FIG. 19 shows the results of transfer and stress measurements of an embodiment of an OFET device according to the invention.

(23) FIG. 20 shows the results of transfer and stress measurements of another embodiment of an OFET device according to the invention.

(24) FIG. 1A exemplarily and schematically depicts a typical bottom gate (BG), top contact (TC) OFET device according to the present invention, comprising a substrate (1), a gate electrode (2), a layer of dielectric material (3) (also known as gate insulator layer), an OSC layer (4), and source and drain (S/D) electrodes (5), and an optional passivation or protection layer (6).

(25) The device of FIG. 1A can be prepared by a process comprising the steps of depositing a gate electrode (2) on a substrate (1), depositing a dielectric layer (3) on top of the gate electrode (2) and the substrate (1), depositing an OSC layer (4) on top of the dielectric layer (3), depositing S/D electrodes (5) on top of the OSC layer (4), and optionally depositing a passivation or protection layer (6) on top of the S/D electrodes (5) and the OSC layer (4).

(26) FIG. 1B exemplarily and schematically depicts a typical bottom gate (BG), bottom contact (BC) OFET device according to the present invention, comprising a substrate (1), a gate electrode (2), a dielectric layer (3), S/D electrodes (5), an OSC layer (4), and an optional passivation or protection layer (6).

(27) The device of FIG. 1B can be prepared by a process comprising the steps of depositing a gate electrode (2) on a substrate (1), depositing a dielectric layer (3) on top of the gate electrode (2) and the substrate (1), depositing S/D electrodes (5) on top of the dielectric layer (3), depositing an OSC layer (4) on top of the S/D electrodes (4) and the dielectric layer (3), and optionally depositing a passivation or protection layer (6) on top of the OSC layer (4).

(28) FIG. 2 exemplarily and schematically depicts a top gate (TG) OFET device according to the present invention, comprising a substrate (1), source and drain electrodes (5), an OSC layer (4), a dielectric layer (3), and a gate electrode (2), and an optional passivation or protection layer (6).

(29) The device of FIG. 2 can be prepared by a process comprising the steps of depositing S/D electrodes (5) on a substrate (1), depositing an OSC layer (4) on top of the S/D electrodes (4) and the substrate (1), depositing a dielectric layer (3) on top of the OSC layer (4), depositing a gate electrode (2) on top of the dielectric layer (3), and optionally depositing a passivation or protection layer (6) on top of the gate electrode (2) and the dielectric layer (3).

(30) The passivation or protection layer (6) in the devices described in FIGS. 1A, 1B and 2 has the purpose of protecting the OSC layer and the S/D or gate electrodes from further layers or devices that may be later provided thereon, and/or from environmental influence.

(31) The distance between the source and drain electrodes (5), as indicated by the double arrow in FIGS. 1A, 1B and 2, is the channel area.

(32) In case of formulations for use in OPV cells, the formulation preferably comprises or contains, more preferably consists essentially of, very preferably exclusively of, a p-type semiconductor and a n-type semiconductor, or an acceptor and a donor material. A preferred material of this type is a blend or mixture of poly(3-substituted thiophene) or P3AT with a C.sub.60 or C.sub.70 fullerene or modified C.sub.60 molecule like PCBM [(6,6)-phenyl C61-butyric acid methyl ester], as disclosed for example in WO 94/05045 A1, wherein preferably the ratio of P3AT to fullerene is from 2:1 to 1:2 by weight, more preferably from 1.2:1 to 1:1.2 by weight.

(33) FIG. 3 and FIG. 4 exemplarily and schematically depict typical and preferred OPV devices according to the present invention [see also Waldauf et al., Appl. Phys. Lett. 89, 233517 (2006)].

(34) An OPV device as shown in FIG. 3 preferably comprises: a low work function electrode (31) (for example a metal, such as aluminum), and a high work function electrode (32) (for example ITO), one of which is transparent, a layer (33) (also referred to as active layer) comprising a hole transporting material and an electron transporting material, preferably selected from OSC materials, situated between the electrodes (31,32); the active layer can exist for example as a bilayer or two distinct layers or blend or mixture of p and n type semiconductor, an optional conducting polymer layer (34), for example comprising a blend of PEDOT:PSS (poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)), situated between the active layer (33) and the high work function electrode (32), to modify the work function of the high work function electrode to provide an ohmic contact for holes, an optional coating (35) (for example of LiF) on the side of the low workfunction electrode (31) facing the active layer (33), to provide an ohmic contact for electrons.

(35) An inverted OPV device as shown in FIG. 4 preferably comprises: a low work function electrode (41) (for example a metal, such as gold), and a high work function electrode (42) (for example ITO), one of which is transparent, a layer (43) (also referred to as active layer) comprising a hole transporting material and an electron transporting material, preferably selected from OSC materials, situated between the electrodes (41,42); the active layer can exist for example as a bilayer or two distinct layers or blend or mixture of p and n type semiconductor, an optional conducting polymer layer (44), for example comprising a blend of PEDOT:PSS, situated between the active layer (43) and the low work function electrode (41) to provide an ohmic contact for electrons, an optional coating (45) (for example of TiO.sub.x) on the side of the high workfunction electrode (42) facing the active layer (43), to provide an ohmic contact for holes.

(36) The OPV devices of the present invent invention typically comprise a p-type (electron donor) semiconductor and an n-type (electron acceptor) semiconductor. The p-type semiconductor is for example a polymer like poly(3-alkyl-thiophene) (P3AT), preferably poly(3-hexylthiophene) (P3HT), or alternatively another selected from the groups of preferred polymeric and monomeric OSC material as listed above. The n-type semiconductor can be an inorganic material such as zinc oxide or cadmium selenide, or an organic material such as a fullerene derivate, for example (6,6)-phenyl-butyric acid methyl ester derivatized methano C.sub.60 fullerene, also known as PCBM or C.sub.60PCBM, as disclosed for example in G. Yu, J. Gao, J. C. Hummelen, F. Wudl, A. J. Heeger, Science 1995, Vol. 270, p. 1789 ff and having the structure shown below, or an structural analogous compound with e.g. a C.sub.70 fullerene group (C.sub.70PCBM), or a polymer (see for example Coakley, K. M. and McGehee, M. D. Chem. Mater. 2004, 16, 4533).

(37) ##STR00189##

(38) A preferred material of this type is a blend or mixture of a polymer like P3HT or another polymer selected from the groups listed above, with a C.sub.60 or C.sub.70 fullerene or modified fullerene like PCBM. Preferably the ratio polymer:fullerene is from 2:1 to 1:2 by weight, more preferably from 1.2:1 to 1:1.2 by weight, most preferably 1:1 by weight. For the blended mixture, an optional annealing step may be necessary to optimize blend morpohology and consequently OPV device performance.

(39) During the process of preparing an OE device, the OSC layer is deposited onto a substrate, followed by removal of the solvent together with any volatile additive(s) present, to form a film or layer.

(40) Various substrates may be used for the fabrication of OE devices, for example glass, ITO coated glass, ITO glass with pre coated layers including PEDOT, PANI etc, or plastics, plastics materials being preferred, examples including alkyd resins, allyl esters, benzocyclobutenes, butadiene-styrene, cellulose, cellulose acetate, epoxide, epoxy polymers, ethylene-chlorotrifluoro ethylene, ethylene-tetra-fluoroethylene, fibre glass enhanced plastic, fluorocarbon polymers, hexafluoropropylenevinylidene-fluoride copolymer, high density polyethylene, parylene, polyamide, polyimide, polyaramid, polydimethylsiloxane, polyethersulphone, polyethylene, polyethylenenaphthalate, polyethyleneterephthalate, polyketone, polymethylmethacrylate, polypropylene, polystyrene, polysulphone, polytetrafluoroethylene, polyurethanes, polyvinylchloride, silicone rubbers, silicones, and flexible films with ITO, or other conducting layers and barrier layers e.g. Vitex film.

(41) Preferred substrate materials are polyethyleneterephthalate, polyimide, and polyethylenenaphthalate. The substrate may be any plastic material, metal or glass coated with the above materials. The substrate should preferably be homogeneous to ensure good pattern definition. The substrate may also be uniformly pre-aligned by extruding, stretching, rubbing or by photochemical techniques to induce the orientation of the organic semiconductor in order to enhance carrier mobility.

(42) The electrodes can be deposited by liquid coating, such as spray-, dip-, web- or spin-coating, or by vacuum deposition or vapor deposition methods. Suitable electrode materials and deposition methods are known to the person skilled in the art. Suitable electrode materials include, without limitation, inorganic or organic materials, or composites of the two. Examples for suitable conductor or electrode materials include polyaniline, polypyrrole, PEDOT or doped conjugated polymers, further dispersions or pastes of graphite or particles of metal such as Au, Ag, Cu, Al, Ni or their mixtures as well as sputter coated or evaporated metals such as Cu, Cr, Pt/Pd or metal oxides such as indium tin oxide (ITO). Organometallic precursors may also be used deposited from a liquid phase.

(43) Preferably, the substrate on surface on which the formulation according to the present invention is applied comprises a surface energy in the range of 130 to 25 mN m.sup.1 more preferably in the range of 115 to 30 mN m.sup.1 determined by measuring the contact angle of at least 2 solvents, e.g. water and methylene iodide, but other solvents can be used. These are typically measured using a contact angle goniometer such as a FTA 1000, at a temperature of 20-25 C. (room temp and at normal atmospheric pressure.the contact angle of the 2 solvents are then combined using a variety of mathematical models, typically Owens-Wendt geometric mean or Wu's harmonic mean. Preferably, the Owens-Wendt method is used.
(1+cos ).sub.LV=2(.sup.D.sub.SV.sup.D.sub.LV+2(.sup.P.sub.SV.sup.P.sub.LV)Owens-Wendt formula
(1+cos ).sub.LV=4{.sup.D.sub.SV.sup.D.sub.LV/(.sup.D.sub.SV+.sup.D.sub.LV)+.sup.P.sub.SV.sup.P.sub.LV/(.sup.P.sub.SV+.sup.P.sub.LV)}Wu's Harmonic mean formula

(44) Deposition of the OSC layer can be achieved by standard methods that are known to the skilled person and are described in the literature. Suitable and preferred deposition methods include liquid coating and printing techniques. Very preferred deposition methods include, without limitation, dip coating, spin coating, spray coating, aerosol jetting, ink jet printing, nozzle printing, gravure printing, doctor blade coating, roller printing, reverse-roller printing, flexographic printing, web printing, spray coating, dip coating, curtain coating, kiss coating, meyer bar coating, 2 roll nip fed coating, anilox coaters, knife coating or slot dye coating. Preferably, the OSC layer is applied with gravure printing, doctor blade coating, roller printing, reverse-roller printing, flexographic printing, web printing, anilox coaters. Gravure and flexographic printing and varients of these printing methods are preferred. These include but or not limited to, micro gravure, reverse gravure, offset gravure, reverse roll etc. Both web fed (roll to roll) and sheetfed in both flatbed and the more conventional on the round configurations can be used.

(45) For flexo printing the anilox can be either chromed steel or ceramic, preferably ceramic. The cell etch can vary between 2 cm.sup.3/m.sup.2 to 120 cm.sup.3/m.sup.2 but most preferably between 3 cm.sup.3/m.sup.2 to 20 cm.sup.3/m.sup.2 and most preferably between 4 cm.sup.3/m.sup.2 to 18 cm.sup.3/m.sup.2, however the dried film thickness will vary on the concentration of the active material and the transfer characteristics of said formulation.

(46) The cell configuration, ie shape, depth, cell wall linking can be adapted by a person skilled in the art to achieve an optimal printing result.

(47) For gravure printing the chromed steel is preferably used but this does not exclude other materials. The engraving requirements are approximately 50% of those for the flexographic printing because there is one less transfer process involved.

(48) The speed can vary significantly depending on the press type and configuration, for flatbed printing the print speed is typically very slow, typically 100 mm/minute or less. On roll to roll presses the speed can exceed 500 m/min.

(49) According to a special aspect, an insulator layer can be deposited on a substrate in order to achieve a special type of an OE according to the present invention. Preferably, the insulator layer is deposited by solution processing, very preferably using a solution of a dielectric material, which is optionally cross-linkable, in one or more organic solvents. Preferably the solvent used for depositing the dielectric material is orthogonal to the solvent used for depositing the OSC material, and vice versa.

(50) When spin coating is used as deposition method, the OSC or dielectric material is spun for example between 1000 and 2000 rpm for a period of for example 30 seconds to give a layer with a typical layer thickness between 0.5 and 1.5 m. After spin coating the film can be heated at an elevated temperature to remove all residual volatile solvents.

(51) If a cross-linkable dielectric is used, it is preferably cross-linked after deposition by exposure to electron beam or electromagnetic (actinic) radiation, like for example X-ray, UV or visible radiation. For example, actinic radiation can be used having a wavelength of from 50 nm to 700 nm, preferably from 200 to 450 nm, most preferably from 300 to 400 nm. Suitable radiation dosages are typically in the range from 25 to 3,000 mJ/cm.sup.2. Suitable radiation sources include mercury, mercury/xenon, mercury/halogen and xenon lamps, argon or xenon laser sources, x-ray, or e-beam. The exposure to actinic radiation will induce a cross-linking reaction in the cross-linkable groups of the dielectric material in the exposed regions. It is also possible for example to use a light source having a wavelength outside the absorption band of the cross-linkable groups, and to add a radiation sensitive photosensitizer to the cross-linkable material.

(52) Optionally the dielectric material layer is annealed after exposure to radiation, for example at a temperature from 70 C. to 130 C., for example for a period of from 1 to 30 minutes, preferably from 1 to 10 minutes. The annealing step at elevated temperature can be used to complete the cross-linking reaction that was induced by the exposure of the cross-linkable groups of the dielectric material to photoradiation.

(53) Removal of the solvent and any volatile additive(s) is preferably achieved by evaporation, for example by exposing the deposited layer to high temperature and/or reduced pressure, preferably at 50 C. to 300 C., more preferably 20 C. to 250 C. According to a special aspect of the present invention, the solvent(s) and any volatile additive can be evaporated under reduced pressure. Preferably either atmospheric pressure or reduced pressure the pressure for solvent evaporation ranges from 10.sup.3 mbar to 1 bar, especially from 10.sup.2 mbar to 100 mbar and more preferably from 0.1 mbar to 10 mbar. Moreover, the evaporation of the solvent can be preferably achieved below the boiling point of the solvent.

(54) The thickness of the dried OSC layer is preferably from 1 nm to 50 m, especially from 2 to 1000 nm and more preferably 3 to 500 nm. Preferred layers comprising organic light emitting materials and/or charge transporting materials can have a thickness in the range of 2 to 150 nm.

(55) Further to the materials and methods as described above and below, the OE device and its components can be prepared from standard materials and standard methods, which are known to the person skilled in the art and described in the literature.

(56) It will be appreciated that variations to the foregoing embodiments of the invention can be made while still falling within the scope of the invention. Each feature disclosed in this specification, unless stated otherwise, may be replaced by alternative features serving the same, equivalent or similar purpose. Thus, unless stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

(57) All of the features disclosed in this specification may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. In particular, the preferred features of the invention are applicable to all aspects of the invention and may be used in any combination. Likewise, features described in non-essential combinations may be used separately (not in combination).

(58) It will be appreciated that many of the features described above, particularly of the preferred embodiments, are inventive in their own right and not just as part of an embodiment of the present invention. Independent protection may be sought for these features in addition to or alternative to any invention presently claimed.

(59) Unless the context clearly indicates otherwise, as used herein plural forms of the terms herein are to be construed as including the singular form and vice versa.

(60) Throughout the description and claims of this specification, the words comprise and contain and variations of the words, for example comprising and comprises, mean including but not limited to, and are not intended to (and do not) exclude other components.

(61) The term polymer includes homopolymers and copolymers, e.g. statistical, alternating or block copolymers. In addition, the term polymer as used hereinafter does also include oligomers and dendrimers. Dendrimers are typically branched macromolecular compounds consisting of a multifunctional core group onto which further branched monomers are added in a regular way giving a tree-like structure, as described e.g. in M. Fischer and F. Vgtle, Angew. Chem., Int. Ed. 1999, 38, 885. The term conjugated polymer means a polymer containing in its backbone (or main chain) mainly C atoms with sp.sup.2-hybridisation, or optionally sp-hybridisation, which may also be replaced by hetero atoms, enabling interaction of one -orbital with another across an intervening -bond. In the simplest case this is for example a backbone with alternating carbon-carbon (or carbon-hetero atom) single and multiple (e.g. double or triple) bonds, but does also include polymers with units like 1,3-phenylene. Mainly means in this connection that a polymer with naturally (spontaneously) occurring defects, which may lead to interruption of the conjugation, is still regarded as a conjugated polymer. Also included in this meaning are polymers wherein the backbone comprises for example units like aryl amines, aryl phosphines and/or certain heterocycles (i.e. conjugation via N-, O-, P- or S-atoms) and/or metal organic complexes (i.e. conjugation via a metal atom). The term conjugated linking group means a group connecting two rings (usually aromatic rings) consisting of C atoms or hetero atoms with sp.sup.2-hybridisation or sp-hybridisation. See also IUPAC Compendium of Chemical terminology, Electronic version.

(62) Unless stated otherwise, the molecular weight is given as the number average molecular weight M.sub.n or as weight average molecular weight M.sub.w, which unless stated otherwise are determined by gel permeation chromatography (GPC) against polystyrene standards.

(63) The degree of polymerization (n) means the number average degree of polymerization, unless stated otherwise given as n=M.sub.n/M.sub.U, wherein M.sub.U is the molecular weight of the single repeating unit.

(64) The term small molecule means a monomeric, i.e. a non-polymeric compound.

(65) Unless stated otherwise, percentages of solids are percent by weight (wt.), percentages or ratios of liquids (like e.g. in solvent mixtures) are percent by volume (vol. %), and all temperatures are given in degrees Celsius ( C.).

(66) Unless stated otherwise, concentrations or proportions of mixture components, given in percentages or ppm are related to the entire formulation including the solvents.

(67) The invention will now be described in more detail by reference to the following examples, which are illustrative only and do not limit the scope of the present invention.

(68) All process steps described above and below can be carried out using known techniques and standard equipment which are described in prior art and are well-known to the skilled person.

EXAMPLES

Example 1

Small Molecule, Flexo Printed, Top Gate

(69) Compound A is a mixture of the following isomers

(70) ##STR00190##

(71) Compound A and its preparation are disclosed in S. Subramanian, J. Anthony et al., J. Am. Chem. Soc. 2008, 130, 2706-2707 (including Supporting Information).

(72) An OFET device was prepared as follows:

(73) Teonex Q65FA film (available from DuPont Teijin Flims) was washed in an ultrasonic methanol bath for 2 minutes and then rinsed with methanol. Approximately 60 nm thick gold source drain electrodes were evaporated with a parallel plate geometry of 20 micron wide by 1000 micron long. The substrate was cleaned with plasma ozone for 1 minutes. The electrodes were treated with Lisicon M001 (available from Merck Chemicals) SAM treatment by spin coating from isopropyl alcohol and evaporating the excess off on a hot plate at 100 C. for 1 min.

(74) An OSC formulation was prepared by dissolving of 1.6 Compound A and 0.4 parts 350 000 Mw polystyrene in 78.4 parts cyclohexylbenzene and 19.6 parts of mesitylene filtering the solution through a 0.2 m PTFE cartridge filter.

(75) Viscosity of 2.2 cP as measured using an AR G-2 rheometer ex TA instruments. The viscosity was measured over a shear rate range of 10 sec.sup.1 to 1000 sec.sup.1 viscosity extrapolated using a Newtonian fit equation, all measurements taken at 25 C.

(76) The OSC formulation was then printed as a 55 cm wide area block on the array of source drain electrodes on PEN film as described above using a RK Flexiproof 100 flexographic printing with a 8 cm.sup.3/m.sup.2 loaded anilox and a Cyrel HiQS flexo mat running at 80 m/min speed. The printed OSC layer was then annealed at 70 C. for 3 minutes.

(77) A dielectric layer of fluoro-polymer Lisicon D139 (9% solids available from Merck Chemicals) was spun on top of the OSC layer on the device and annealed at 100 C. for 2 minutes to give a dry dielectric film of approximately 1 micron thick.

(78) Finally a 40 nm thick gold gate electrode array of evaporated on top of the dielectric layer in such a way that it covered the existing source drain electrode structures.

(79) The transfer and stress measurements of the OFET device was performed by using Keithley 4200. The transistor transfer characteristic and the linear and saturation mobility are depicted in FIG. 5.

Example 2

Small Molecule, Flexo Printed, Top Gate

(80) An OFET device was prepared as follows:

(81) Teonex Q65FA film (available from DuPont Teijin Flims) was washed in an ultrasonic methanol bath for 2 minutes and then rinsed with methanol. Approximately 60 nm thick gold source drain electrodes were evaporated with a parallel plate geometry of 20 micron wide by 1000 micron long. The substrate was cleaned with plasma ozone for 1 minutes. The electrodes were treated with Lisicon M001 (available from Merck Chemicals) SAM treatment by spin coating from isopropyl alcohol and evaporating the excess off on a hot plate at 100 C. for 1 min.

(82) An OSC formulation was prepared by dissolving of 1.3 parts Compound A (as mentioned in Example 1) and 0.7 parts 350 000 Mw polystyrene in 78.4 parts cyclohexylbenzene and 19.6 parts of mesitylene filtering the solution through a 0.2 m PTFE cartridge filter.

(83) Viscosity of 2.3 cP as measured using an AR G-2 rheometer ex TA instruments. The viscosity was measured over a shear rate range of 10 sec.sup.1 to 1000 sec.sup.1 viscosity extrapolated using a Newtonian fit equation, all measurements taken at 25 C.

(84) The OSC formulation was then printed as a 55 cm wide area block on the array of source drain electrodes on PEN film as described above using a RK Flexiproof 100 flexographic printing with a 8 cm.sup.3/m.sup.2 loaded anilox and a Cyrel HiQS flexo mat running at 80 m/min speed. The printed OSC layer was then annealed at 70 C. for 3 minutes.

(85) A dielectric layer of fluoro-polymer Lisicon D139 (9% solids available from Merck Chemicals) was spun on top of the OSC layer on the device and annealed at 100 C. for 2 minutes to give a dry dielectric film of approximately 1 micron thick.

(86) Finally a 40 nm thick gold gate electrode array of evaporated on top of the dielectric layer in such a way that it covered the existing source drain electrode structures.

(87) The transfer and stress measurements of the OFET device was performed by using Keithley 4200. The transistor transfer characteristic and the linear and saturation mobility are depicted in FIG. 6.

Example 3

Small Molecule, Flexo Printed, Top Gate

(88) An OFET device was prepared as follows:

(89) Teonex Q65FA film (available from DuPont Teijin Flims) was washed in an ultrasonic methanol bath for 2 minutes and then rinsed with methanol. Approximately 60 nm thick gold source drain electrodes were evaporated with a parallel plate geometry of 20 micron wide by 1000 micron long. The substrate was cleaned with plasma ozone for 1 minutes. The electrodes were treated with Lisicon M001 (available from Merck Chemicals) SAM treatment by spin coating from isopropyl alcohol and evaporating the excess off on a hot plate at 100 C. for 1 min.

(90) An OSC formulation was prepared by dissolving of 1.3 parts Compound A (as mentioned in Example 1) and 0.7 parts 350 000 Mw polystyrene in 58.8 parts cyclohexylbenzene and 39.2 parts of mesitylene filtering the solution through a 0.2 m PTFE cartridge filter.

(91) Viscosity of 1.6 cP as measured using an AR G-2 rheometer ex TA instruments. The viscosity was measured over a shear rate range of 10 sec.sup.1 to 1000 sec.sup.1 viscosity extrapolated using a Newtonian fit equation, all measurements taken at 25 C.

(92) The OSC formulation was then printed as a 55 cm wide area block on the array of source drain electrodes on PEN film as described above using a RK Flexiproof 100 flexographic printing with a 8 cm.sup.3/m.sup.2 loaded anilox and a Cyrel HiQS flexo mat running at 80 m/min speed. The printed OSC layer was then annealed at 70 C. for 3 minutes.

(93) A dielectric layer of fluoro-polymer Lisicon D139 (9% solids available from Merck Chemicals) was spun on top of the OSC layer on the device and annealed at 100 C. for 2 minutes to give a dry dielectric film of approximately 1 micron thick.

(94) Finally a 40 nm thick gold gate electrode array of evaporated on top of the dielectric layer in such a way that it covered the existing source drain electrode structures.

(95) The transfer and stress measurements of the OFET device was performed by using Keithley 4200. The transistor transfer characteristic and the linear and saturation mobility are depicted in FIG. 7.

Example 4

Small Molecule, Gravure Printed, Top Gate

(96) An OFET device was prepared as follows:

(97) Teonex Q65FA film (available from DuPont Teijin Flims) was washed in an ultrasonic methanol bath for 2 minutes and then rinsed with methanol. Approximately 60 nm thick gold source drain electrodes were evaporated with a parallel plate geometry of 20 micron wide by 1000 micron long. The substrate was cleaned with a 500 W argon plasma for 1 minute. The electrodes were treated with Lisicon M001 (available from Merck Chemicals) SAM treatment by spin coating from isopropyl alcohol and evaporating the excess off on a hot plate at 100 C. for 1 min.

(98) OSC formulation was prepared by dissolving of 1.6 parts Compound A (as mentioned in Example 1) and 0.4 parts 350000 Mw polystyrene in 78.4 parts cyclohexylbenzene and 19.6 parts o-xylene and filtering the solution through a 0.2 m PTFE cartridge filter.

(99) Viscosity of 2.23 cP as measured using an AR G-2 rheometer ex TA instruments. The viscosity was measured over a shear rate range of 10 sec.sup.1 to 1000 sec.sup.1 viscosity extrapolated using a Newtonian fit equation, all measurements taken at 25 C.

(100) The OSC formulation was then gravure printed as a wide area block on the array of source drain electrodes on PEN film as described above using a RK Flexiproof 100 printer by directly contacting a 8 cm.sup.3/m.sup.2 loaded anilox running at 90 m/min speed with the PEN substrate. The printed OSC layer was then annealed at 70 C. for 3 minutes.

(101) A dielectric layer of fluoro-polymer Lisicon D139 (9% solids available from Merck Chemicals) was spun on top of the OSC layer on the device and annealed at 100 C. for 2 minutes to give a dry dielectric film of approximately 1 micron thick.

(102) Finally a 40 nm thick gold gate electrode array of evaporated on top of the dielectric layer in such a way that it covered the existing source drain electrode structures.

(103) The transfer and stress measurements of the OFET device was performed by using Keithley 4200. The transistor transfer characteristic and the linear and saturation mobility are depicted in FIG. 8.

Example 5

Small Molecule, Flexo Printed, Bottom Gate

(104) An OFET device was prepared as follows:

(105) Teonex Q65FA (PEN) film (available from DuPont Teijin Flims) was washed in an ultrasonic methanol bath for 3 minutes and then rinsed with methanol. Approximately 40 nm thick gold gate electrode were evaporated on top of the PEN substrate. A dielectric layer of D206 available (from Merck Chemicals) was spun on top of the gold gate electrode, at a spin speed of 1500 rpm for 30 seconds; annealed at 120 C. for 1 minute, and then UV cured under UV light (302 nm) for 5 minutes. Approximately 40 nm thick gold source drain electrodes were evaporated. The electrodes were treated with Lisicon M001 (available from Merck Chemicals) SAM treatment by spin coating from isopropyl alcohol and then rinsed with IPA and spin dried evaporating the excess off on a hot plate at 100 C. for 1 min.

(106) An OSC formulation was prepared by dissolving of 1.6 parts Compound A (as mentioned in Example 1) and 0.4 parts 6 000 000 Mw polystyrene in mesitylene filtering the solution through a 0.2 m PTFE cartridge filter.

(107) Viscosity of 3.6 cP as measured using an AR G-2 rheometer ex TA instruments. The viscosity was measured over a shear rate range of 10 sec.sup.1 to 1000 sec.sup.1 viscosity extrapolated using a Newtonian fit equation, all measurements taken at 25 C.

(108) The OSC formulation was then printed as a 55 cm wide area block on the array of source drain electrodes on PEN film as described above using a RK Flexiproof 100 flexographic printing with a 8 cm.sup.3/m.sup.2 loaded anilox and a Cyrel HiQS flexo mat running at 80 m/min speed. The printed OSC layer was then annealed at 70 C. for 3 minutes.

(109) The transfer and stress measurements of the OFET device was performed by using Keithley 4200. The transistor transfer characteristic and the linear and saturation mobility are depicted in FIG. 9.

Example 6

Small Molecule, Flexo Printed, Bottom Gate

(110) An OFET device was prepared as follows:

(111) Teonex Q65FA (PEN) film (available from DuPont Teijin Flims) was washed in an ultrasonic methanol bath for 3 minutes and then rinsed with methanol. Approximately 40 nm thick gold gate electrode were evaporated on top of the PEN substrate. A dielectric layer of D206 available (from Merck Chemicals) was spun on top of the gold gate electrode, at a spin speed of 1500 rpm for 30 seconds; annealed at 120 C. for 1 minute, and then UV cured under UV light (302 nm) for 5 minutes. Approximately 40 nm thick gold source drain electrodes were evaporated. The electrodes were treated with Lisicon M001 (available from Merck Chemicals) SAM treatment by spin coating from isopropyl alcohol and then rinsed with IPA and spin dried evaporating the excess off on a hot plate at 100 C. for 1 min.

(112) An OSC formulation was prepared by dissolving of 1.6 parts Compound A (as mentioned in Example 1) and 0.4 parts 6 000 000 Mw polystyrene in cyclohexylbenzene/mesitylene in a 1:1 blend filtering the solution through a 0.2 m PTFE cartridge filter.

(113) Viscosity of 5.6 cP as measured using an AR G-2 rheometer ex TA instruments. The viscosity was measured over a shear rate range of 10 sec.sup.1 to 1000 sec.sup.1 viscosity extrapolated using a Newtonian fit equation, all measurements taken at 25 C.

(114) The OSC formulation was then printed as a 55 cm wide area block on the array of source drain electrodes on PEN film as described above using a RK Flexiproof 100 flexographic printing with a 8 cm.sup.3/m.sup.2 loaded anilox and a Cyrel HiQS flexo mat running at 80 m/min speed. The printed OSC layer was then annealed at 70 C. for 3 minutes.

(115) The transfer and stress measurements of the OFET device was performed by using Keithley 4200. The transistor transfer characteristic and the linear and saturation mobility are depicted in FIG. 10.

Example 7

Polymer, Flexo Printed, Top Gate

(116) An OFET device was prepared as follows:

(117) Teonex Q65FA film (available from DuPont Teijin Flims) was washed in an ultrasonic methanol bath for 2 minutes and then rinsed with methanol. Approximately 60 nm thick gold source drain electrodes were evaporated with a parallel plate geometry of 20 micron wide by 1000 micron long. The substrate was cleaned with plasma ozone for 1 minutes. The electrodes were treated with Lisicon M001 (available from Merck Chemicals) SAM treatment by spin coating from methoxy propanol and evaporating the excess off on a hot plate at 100 C. for 1 min.

(118) An OSC formulation was prepared by dissolving of 1% polymer comprising phenanthrene units having the following structure

(119) ##STR00191##
and a weight average molecular weight of 78,000 in mesitylene filtering the solution through a 0.2 m PTFE cartridge filter.

(120) Viscosity of 6.1 cP as measured using an AR G-2 rheometer ex TA instruments. The viscosity was measured over a shear rate range of 10 sec.sup.1 to 1000 sec.sup.1 viscosity extrapolated using a Newtonian fit equation, all measurements taken at 25 C.

(121) The OSC formulation was then printed as a 55 cm wide area block on the array of source drain electrodes on PEN film as described above using a RK Flexiproof 100 flexographic printing with a 8 cm.sup.3/m.sup.2 loaded anilox and a Cyrel HiQS flexo mat running at 80 m/min speed. The printed OSC layer was then annealed at 70 C. for 3 minutes.

(122) A dielectric layer of fluoro-polymer Lisicon D139 (9% solids available from Merck Chemicals) was spun on top of the OSC layer on the device and annealed at 100 C. for 2 minutes to give a dry dielectric film of approximately 1 micron thick.

(123) Finally a 40 nm thick gold gate electrode array of evaporated on top of the dielectric layer in such a way that it covered the existing source drain electrode structures.

(124) The transfer and stress measurements of the OFET device was performed by using Keithley 4200. The transistor transfer characteristic and the linear and saturation mobility are depicted in FIG. 11.

Example 8

Small Molecule, Flexo Printed, Bottom Gate

(125) An OFET device was prepared as follows:

(126) Teonex Q65FA (PEN) film (available from DuPont Teijin Flims) was washed in an ultrasonic methanol bath for 3 minutes and then rinsed with methanol. Approximately 40 nm thick gold gate electrode were evaporated on top of the PEN substrate. A dielectric layer of D206 available (from Merck Chemicals) was spun on top of the gold gate electrode, at a spin speed of 1500 rpm for 30 seconds; annealed at 120 C. for 1 minute, and then UV cured under UV light (302 nm) for 5 minutes. Approximately 40 nm thick gold source drain electrodes were evaporated. The electrodes were treated with Lisicon M001 (available from Merck Chemicals) SAM treatment by spin coating from isopropyl alcohol and then rinsed with IPA and spin dried evaporating the excess off on a hot plate at 100 C. for 1 min.

(127) An OSC formulation was prepared by dissolving of 1.6 parts Compound A (as mentioned in Example 1) and 0.4 parts 6 000 000 Mw polystyrene in cyclohexylbenzene, filtering the solution through a 0.2 m PTFE cartridge filter.

(128) Viscosity of 6.5 cP as measured using an AR G-2 rheometer ex TA instruments. The viscosity was measured over a shear rate range of 10 sec.sup.1 to 1000 sec.sup.1 viscosity extrapolated using a Newtonian fit equation, all measurements taken at 25 C.

(129) The OSC formulation was then printed as a 55 cm wide area block on the array of source drain electrodes on PEN film as described above using a RK Flexiproof 100 flexographic printing with a 8 cm.sup.3/m.sup.2 loaded anilox and a Cyrel HiQS flexo mat running at 80 m/min speed. The printed OSC layer was then annealed at 70 C. for 3 minutes.

(130) The transfer and stress measurements of the OFET device was performed by using Keithley 4200. The transistor transfer characteristic and the linear and saturation mobility are depicted in FIG. 12.

Example 9

Small Molecule, Gravure Printed, Bottom Gate, Mesitylene/CHB

(131) Teonex Q65FA (PEN) film (available from DuPont Teijin Flims) was washed in an ultrasonic methanol bath for 2 minutes and then rinsed with methanol. Approximately 50 nm thick gold gate electrode were evaporated on top of the PEN substrate. A dielectric layer of D206 available (from Merck Chemicals) was spun on top of the gold gate electrode, at a spin speed of 1500 rpm for 30 seconds; annealed at 100 C. for 10 minute, and then UV cured under UV light (306 nm) for 5 minutes. Approximately 60 nm thick gold source drain electrodes were evaporated. The electrodes were treated with M001 (available from Merck Chemicals) SAM treatment by covering for 1 min and then spin coating to remove excess M001 and then rinsed with IPA and spin dried evaporating the excess off on a hot plate at 100 C. for 1 min.

(132) An OSC formulation was prepared by dissolving of 1.6 parts Compound A and 0.4 parts 6000000 Mw polystyrene in cyclohexylbenzene/mesitylene (1:1) filtering the solution through a 0.2 m PTFE cartridge filter. Viscosity of 5.6 cP as measured using an AR G-2 rheometer ex TA Instruments. The viscosity was measured over a shear rate range of 10 sec.sup.1 to 1000 sec.sup.1 viscosity extrapolated using a Newtonian fit equation, all measurements taken at 25 C.

(133) The OSC formulation was then printed using a CP 90-100-13 Sauerressig lab proofer. The gravure cylinder had many cell depths in order to achieve different volumes. The Anilox was 6.8 ml/m.sup.2. The doctor blade was put into contact with the gravure cylinder, the formulation was placed in the nip between the doctor blade and the gravure cylinder and then rotated by hand. The print head was then slowly pulled over the substrate. The printed OSC layer was then annealed (forced air) at 70 C. for 4 minutes.

(134) The transfer and stress measurements of the OFET device was performed by using Keithley 4200. The transistor transfer characteristic and the linear and saturation mobility are depicted in FIG. 13.

Example 10

Small Molecule, Gravure Printed, Top Gate

(135) Teonex Q65FA film (available from DuPont Teijin Flims) was washed in an ultrasonic methanol bath for 2 minutes and then rinsed with methanol. Approximately 60 nm thick gold source drain electrodes were evaporated with a parallel plate geometry of 20 micron wide by 1000 micron long. The substrate was cleaned with a 1000 W oxygen plasma for 1 minute. The electrodes were treated with M001 (available from Merck Chemicals) SAM treatment by depositing a film and leaving for 1 minute and then spinning-off excess and evaporating the excess off on a hot plate at 100 C. for 1 min.

(136) An OSC formulation was prepared by dissolving of 1.6 parts Compound A and 0.4 parts 6000000 Mw polystyrene in cyclohexylbenzene/mesitylene (1:1) filtering the solution through a 0.2 m PTFE cartridge filter. Viscosity of 5.6 cP as measured using an AR G-2 rheometer ex TA Instruments. The viscosity was measured over a shear rate range of 10 sec.sup.1 to 1000 sec.sup.1 viscosity extrapolated using a Newtonian fit equation, all measurements taken at 25 C.

(137) The OSC formulation was then printed using a CP 90-100-13 Sauerressig lab proofer. The gravure cylinder had many cell depths in order to achieve different volumes. The doctor blade was put into contact with the gravure cylinder, the formulation was placed in the nip between the doctor blade and the gravure cylinder and then rotated by hand. The print head was then slowly pulled over the substrate. The printed OSC layer was then annealed at 70 C. for 4 minutes.

(138) A dielectric layer of fluoro-polymer D139 (9% solids available from Merck Chemicals) was spun on top of the OSC layer on the device and annealed at 70 C. for 3 minutes and then 100 C for 1 minute, to give a dry dielectric film of approximately 1 micron thick.

(139) Finally a 50 nm thick gold gate electrode array of evaporated on top of the dielectric layer in such a way that it covered the existing source drain electrode structures.

(140) The transfer and stress measurements of the OFET device was performed by using Keithley 4200. The transistor transfer characteristic and the linear and saturation mobility are depicted in FIG. 14.

Example 11

Small Molecule, Flexo Printed, Top Gate, in Dimethoxytoluene

(141) An OFET device was prepared as follows:

(142) Teonex Q65FA film (available from DuPont Teijin Flims) was washed in an ultrasonic methanol bath for 2 minutes and then rinsed with methanol. Approximately 60 nm thick gold source drain electrodes were evaporated with a parallel plate geometry of 20 micron wide by 1000 micron long. The substrate was cleaned with plasma ozone for 1 minutes. The electrodes were treated with Lisicon M001 (available from Merck Chemicals) SAM treatment by spin coating from isopropyl alcohol and evaporating the excess off on a hot plate at 100 C. for 1 min.

(143) An OSC formulation was prepared by dissolving of 1.0 parts Compound A (as mentioned in Example 1) and 1.0 parts PTAA in dimethoxytoluene filtering the solution through a 0.2 m PTFE cartridge filter.

(144) Viscosity of 5.0 cP as measured using an AR G-2 rheometer ex TA instruments. The viscosity was measured over a shear rate range of 10 sec-1 to 1000 sec-1 viscosity extrapolated using a Newtonian fit equation, all measurements taken at 25 C.

(145) The OSC formulation was then printed as a 55 cm wide area block on the array of source drain electrodes on PEN film as described above using a RK Flexiproof 100 flexographic printing with a 8 cm3/m2 loaded anilox and a Cyrel HiQS flexo mat running at 80 m/min speed. The printed OSC layer was then annealed at 70 C. for 3 minutes.

(146) A dielectric layer of fluoro-polymer Lisicon D139 (9% solids available from Merck Chemicals) was spun on top of the OSC layer on the device and annealed at 100 C. for 2 minutes to give a dry dielectric film of approximately 1 micron thick.

(147) Finally a 40 nm thick gold gate electrode array of evaporated on top of the dielectric layer in such a way that it covered the existing source drain electrode structures.

(148) The transfer and stress measurements of the OFET device was performed by using Keithley 4200. The transistor transfer characteristic is depicted in FIG. 15a and the linear and saturation mobility are depicted in FIG. 15b.

Example 12

Small Molecule, Flexo Printed, Top Gate, in Isochroman

(149) An OFET device was prepared as follows:

(150) Teonex Q65FA film (available from DuPont Teijin Flims) was washed in an ultrasonic methanol bath for 2 minutes and then rinsed with methanol.

(151) Approximately 60 nm thick gold source drain electrodes were evaporated with a parallel plate geometry of 20 micron wide by 1000 micron long. The substrate was cleaned with plasma ozone for 1 minutes. The electrodes were treated with Lisicon M001 (available from Merck Chemicals) SAM treatment by spin coating from isopropyl alcohol and evaporating the excess off on a hot plate at 100 C. for 1 min.

(152) An OSC formulation was prepared by dissolving of 1.0 parts Compound A (as mentioned in Example 1) and 1.0 parts polytriarylamine (PTAA) in isochroman 95 parts and 1-methy naphthalene 3 parts filtering the solution through a 0.2 m PTFE cartridge filter.

(153) Viscosity of 5.3 cP as measured using an AR G-2 rheometer ex TA instruments. The viscosity was measured over a shear rate range of 10 sec-1 to 1000 sec-1 viscosity extrapolated using a Newtonian fit equation, all measurements taken at 25 C.

(154) The OSC formulation was then printed as a 55 cm wide area block on the array of source drain electrodes on PEN film as described above using a RK Flexiproof 100 flexographic printing with a 8 cm3/m2 loaded anilox and a Cyrel HiQS flexo mat running at 80 m/min speed. The printed OSC layer was then annealed at 70 C. for 3 minutes.

(155) A dielectric layer of fluoro-polymer Lisicon D139 (9% solids available from Merck Chemicals) was spun on top of the OSC layer on the device and annealed at 100 C. for 2 minutes to give a dry dielectric film of approximately 1 micron thick.

(156) Finally a 40 nm thick gold gate electrode array of evaporated on top of the dielectric layer in such a way that it covered the existing source drain electrode structures.

(157) The transfer and stress measurements of the OFET device was performed by using Keithley 4200. The transistor transfer characteristic and the linear and saturation mobility are depicted in FIG. 16.

Example 13

Small Molecule, Flexo Printed, Top Gate, in Tetralin

(158) An OFET device was prepared as follows:

(159) Teonex Q65FA film (available from DuPont Teijin Flims) was washed in an ultrasonic methanol bath for 2 minutes and then rinsed with methanol. Approximately 60 nm thick gold source drain electrodes were evaporated with a parallel plate geometry of 20 micron wide by 1000 micron long. The substrate was cleaned with plasma ozone for 1 minutes. The electrodes were treated with Lisicon M001 (available from Merck Chemicals) SAM treatment by spin coating from isopropyl alcohol and evaporating the excess off on a hot plate at 100 C. for 1 min.

(160) An OSC formulation was prepared by dissolving of 1.0 parts Compound A (as mentioned in Example 1) and 1.0 parts PTAA in tetralin filtering the solution through a 0.2 m PTFE cartridge filter.

(161) Viscosity of 2.9 cP as measured using an AR G-2 rheometer ex TA instruments. The viscosity was measured over a shear rate range of 10 sec-1 to 1000 sec-1 viscosity extrapolated using a Newtonian fit equation, all measurements taken at 25 C.

(162) The OSC formulation was then printed as a 55 cm wide area block on the array of source drain electrodes on PEN film as described above using a RK Flexiproof 100 flexographic printing with a 8 cm3/m2 loaded anilox and a Cyrel HiQS flexo mat running at 80 m/min speed. The printed OSC layer was then annealed at 70 C. for 3 minutes.

(163) A dielectric layer of fluoro-polymer Lisicon D139 (9% solids available from Merck Chemicals) was spun on top of the OSC layer on the device and annealed at 100 C. for 2 minutes to give a dry dielectric film of approximately 1 micron thick.

(164) Finally a 40 nm thick gold gate electrode array of evaporated on top of the dielectric layer in such a way that it covered the existing source drain electrode structures.

(165) The transfer and stress measurements of the OFET device was performed by using Keithley 4200. The transistor transfer characteristic is depicted in FIG. 17a and the linear and saturation mobility are depicted in FIG. 17b.

Example 14

Small Molecule, Flexo Printed, Top Gate, Butyl Phenyl Ether

(166) An OFET device was prepared as follows:

(167) Teonex Q65FA film (available from DuPont Teijin Flims) was washed in an ultrasonic methanol bath for 2 minutes and then rinsed with methanol. Approximately 60 nm thick gold source drain electrodes were evaporated with a parallel plate geometry of 20 micron wide by 1000 micron long. The substrate was cleaned with plasma ozone for 1 minutes. The electrodes were treated with Lisicon M001 (available from Merck Chemicals) SAM treatment by spin coating from isopropyl alcohol and evaporating the excess off on a hot plate at 100 C. for 1 min.

(168) An OSC formulation was prepared by dissolving of 1.6 parts Compound A (as mentioned in Example 1) and 0.4 parts Poly (alpha)methylstyrene having a weight average molecular weight below 10,000 g/mol in butyl phenyl ether filtering the solution through a 0.2 m PTFE cartridge filter.

(169) Viscosity of 1.6 cP as measured using an AR G-2 rheometer ex TA instruments. The viscosity was measured over a shear rate range of 10 sec-1 to 1000 sec-1 viscosity extrapolated using a Newtonian fit equation, all measurements taken at 25 C.

(170) The OSC formulation was then printed as a 55 cm wide area block on the array of source drain electrodes on PEN film as described above using a RK Flexiproof 100 flexographic printing with a 8 cm.sup.3/m.sup.2 loaded anilox and a Cyrel HiQS flexo mat running at 80 m/min speed. The printed OSC layer was then annealed at 70 C. for 3 minutes.

(171) A dielectric layer of fluoro-polymer Lisicon D139 (9% solids available from Merck Chemicals) was spun on top of the OSC layer on the device and annealed at 100 C. for 2 minutes to give a dry dielectric film of approximately 1 micron thick.

(172) Finally a 40 nm thick gold gate electrode array of evaporated on top of the dielectric layer in such a way that it covered the existing source drain electrode structures.

(173) The transfer and stress measurements of the OFET device was performed by using Keithley 4200. The transistor transfer characteristic and the linear and saturation mobility are depicted in FIG. 18.

Example 15

Small Molecule, Flexo Printed, Bottom Gate

(174) An OFET device was prepared as follows:

(175) Teonex Q65FA (PEN) film (available from DuPont Teijin Flims) was washed in an ultrasonic methanol bath for 3 minutes and then rinsed with methanol. Approximately 40 nm thick gold gate electrode were evaporated on top of the PEN substrate. A dielectric layer of D206 available (from Merck Chemicals) was spun on top of the gold gate electrode, at a spin speed of 1500 rpm for 30 seconds; annealed at 120 C. for 1 minute, and then UV cured under UV light (302 nm) for 5 minutes. Approximately 40 nm thick gold source drain electrodes were evaporated. The electrodes were treated with Lisicon M001 (available from Merck Chemicals) SAM treatment by spin coating from isopropyl alcohol and then rinsed with IPA and spin dried evaporating the excess off on a hot plate at 100 C. for 1 min.

(176) An OSC formulation was prepared by dissolving of 1.6 parts Compound A (as mentioned in Example 1) and 0.4 parts 6 000 000 Mw polystyrene in cyclohexylbenzene/mesitylene in a 60/40 blend filtering the solution through a 0.2 m PTFE cartridge filter.

(177) Viscosity of 8 cP as measured using an AR G-2 rheometer ex TA instruments. The viscosity was measured over a shear rate range of 10 sec.sup.1 to 1000 sec.sup.1 viscosity extrapolated using a Newtonian fit equation, all measurements taken at 25 C.

(178) The OSC formulation was then printed as a 55 cm wide area block on the array of source drain electrodes on PEN film as described above using a RK Flexiproof 100 flexographic printing with a 8 cm.sup.3/m.sup.2 loaded anilox and a Cyrel HiQS flexo mat running at 80 m/min speed. The printed OSC layer was then annealed at 70 C. for 3 minutes.

(179) The transfer and stress measurements of the OFET device was performed by using Keithley 4200. The transistor transfer characteristic and the linear and saturation mobility are depicted in FIG. 19.

Example 16

Small Molecule, Flexo Printed, Bottom Gate

(180) An OFET device was prepared as follows:

(181) Teonex Q65FA (PEN) film (available from DuPont Teijin Flims) was washed in an ultrasonic methanol bath for 3 minutes and then rinsed with methanol. Approximately 40 nm thick gold gate electrode were evaporated on top of the PEN substrate. A dielectric layer of D206 available (from Merck Chemicals) was spun on top of the gold gate electrode, at a spin speed of 1500 rpm for 30 seconds; annealed at 120 C. for 1 minute, and then UV cured under UV light (302 nm) for 5 minutes. Approximately 40 nm thick gold source drain electrodes were evaporated. The electrodes were treated with Lisicon M001 (available from Merck Chemicals) SAM treatment by spin coating from isopropyl alcohol and then rinsed with IPA and spin dried evaporating the excess off on a hot plate at 100 C. for 1 min.

(182) An OSC formulation was prepared by dissolving of 1.6 parts Compound A (as mentioned in Example 1) and 0.5 parts 6 000 000 Mw polystyrene in cyclohexylbenzene/mesitylene in a 60:40 blend filtering the solution through a 0.2 m PTFE cartridge filter.

(183) Viscosity of 10 cP as measured using an AR G-2 rheometer ex TA instruments. The viscosity was measured over a shear rate range of 10 sec.sup.1 to 1000 sec.sup.1 viscosity extrapolated using a Newtonian fit equation, all measurements taken at 25 C.

(184) The OSC formulation was then printed as a 55 cm wide area block on the array of source drain electrodes on PEN film as described above using a RK Flexiproof 100 flexographic printing with a 8 cm.sup.3/m.sup.2 loaded anilox and a Cyrel HiQS flexo mat running at 80 m/min speed. The printed OSC layer was then annealed at 70 C. for 3 minutes.

(185) The transfer and stress measurements of the OFET device was performed by using Keithley 4200. The transistor transfer characteristic and the linear and saturation mobility are depicted in FIG. 20.