CROSSLINKABLE POLYMERIC MATERIALS FOR DIELECTRIC LAYERS IN ELECTRONIC DEVICES
20210143348 · 2021-05-13
Inventors
Cpc classification
C08F20/40
CHEMISTRY; METALLURGY
H10K85/141
ELECTRICITY
C08F20/28
CHEMISTRY; METALLURGY
International classification
C08F20/28
CHEMISTRY; METALLURGY
C08F20/40
CHEMISTRY; METALLURGY
Abstract
Compositions for providing a dielectric layer in an electronic device wherein the composition comprises a polymer which polymer contains one or more building blocks, wherein at least 25 mol % of the total number of building blocks in the polymer are of the general formula having olefinic oligo-dihydrodicyclopentadienyl functionalities.
Claims
1. A composition for providing a dielectric layer in an electronic device, the composition comprising: a polymer containing one or more units, wherein at least 25 mol % of the total number of units in the polymer are the following units (A) with crosslinkable side groups, ##STR00007## in which X independently at each occurrence is a methylene group or oxygen, R independently at each occurrence is a methyl group or hydrogen, L.sub.1 is a divalent group which connects the polymer chain to the side group, and L.sub.2 is a divalent group which connects the polymer chain to the side group.
2. The composition according to claim 1, wherein L.sub.1 is selected from the group consisting of carbonyl, carbonyloxyethyl, carbonyloxyisopropyl, carbonyloxyethylamide, phenyl and benzyl groups; X is CH.sub.2; R independently is CH.sub.3 or H; n is 0.
3. The composition according to claim 1, wherein L.sub.1 is a carbonyl or carbonyloxyethyl group; R is CH.sub.3 or H n is 0.
4. The composition according to claim 1, wherein L.sub.1,2 is a carbonyl unit; X is CH.sub.2; R is H. n is 0.
5-6. (canceled)
7. The composition according to claim 1, wherein the polymer further comprises a unit derived from a methacrylate having a linear, branched or cyclic hydrocarbon group which comprises 1-18 carbon atoms.
8. The composition according to claim 1, wherein the polymer further comprises a unit derived from any of claims 1 to 7, characterized in that a further unit comprises styrene, ethylene, methyl vinyl ether or octadecene.
9. The composition according to claim 1, wherein the polymer further comprises one of the following units or combination of units: ##STR00008## ##STR00009##
10-15. (canceled)
16. The composition according to claim 7, wherein at least some hydrogen atoms of the hydrocarbon group are substituted with fluorine atoms.
17. An electronic device comprising at least one dielectric layer, wherein the at least one dielectric layer comprises: a) a crosslinked polymer obtained by polymerizing monomers to obtain a polymer including at least 25 mol % of the following units (A) with crosslinkable side groups, and then crosslinking the crosslinkable side groups: ##STR00010## in which X independently at each occurrence is a methylene group or oxygen, R independently at each occurrence is a methyl group or hydrogen, L.sub.1 is a divalent group which connects the polymer chain to the side group and L.sub.2 is a divalent group which connects the polymer chain to the side group.
18. An electronic device comprising a thin-film capacitor including at least one dielectric layer, wherein the at least one dielectric layer comprises: a) a crosslinked polymer obtained by polymerizing monomers to obtain a polymer including at least 25 mol % of the following units (A) with crosslinkable side groups, and then crosslinking the crosslinkable side groups: ##STR00011## in which X independently at each occurrence is a methylene group or oxygen, R independently at each occurrence is a methyl group or hydrogen, L.sub.1 is a divalent group which connects the polymer chain to the side group, and L.sub.2 is a divalent group which connects the polymer chain to the side group.
19. The electronic device according to claim 17, further comprising an additional polymer.
20. The electronic device according to claim 17, further comprising one or more of a free radical photoinitiator, a stabilizer, and an adhesion promoter.
Description
BRIEF DESCRIPTION OF FIGURES
[0103] The drawings are not necessarily to scale. For reasons of clarity and for greater ease of representation, certain features of the invention may be shown with exaggerated size or in schematic form, and similarly, certain details of conventional or known elements may therefore not be shown.
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[0111] The various embodiments of the present invention, as for example but not exclusively those of the various dependent claims, may be combined with one another in any desired way.
[0112] The invention is now elucidated with reference to the non-limiting examples below.
EXAMPLES
Example A1 Preparation of Polymer 1
[0113] Using a syringe technique, 20 ml of freshly distilled dicyclopentenyloxyethyl methacrylate (FA-512M, Hitachi Chemical) and 20 ml of THF were transferred under argon into a two-necked flask. Then 30 mg of 2,2′-azobisisobutyronitrile in the form of a THF solution were added, and the mixture was heated to 60° C. with stirring. After six hours, the reaction was discontinued by addition of 50 mg of butylated hydroxytoluene (BHT) and cooling to room temperature. The polymerization solution was precipitated from 1000 ml of methanol, and the polymer was isolated by filtration and dried under reduced pressure. The polymer was then dissolved again three times in 100 ml of THF and precipitated from 800 ml of methanol with addition of 20 mg of BHT each time.
[0114] Yield 20.2%
[0115] Mn=219 000 g/mol, Mw=520 000 g/mol
[0116] T.sub.g=61° C.
Example A2 Preparation of Polymer 2
[0117] Using a syringe technique, 20 ml of freshly distilled dicyclopentenyl methacrylate (CD535, Sartomer) and 20 ml of THF were transferred under argon into a two-necked flask. Then 40 mg of 2,2′-azobisisobutyronitrile in the form of a THF solution were added, and the mixture was heated to 50° C. with stirring. After ten hours, the reaction was discontinued by addition of 50 mg of butylated hydroxytoluene (BHT) and cooling to room temperature. The polymerization solution was precipitated from 1000 ml of methanol, and the polymer was isolated by filtration and dried under reduced pressure. The polymer was then dissolved again three times in 100 ml of THF and precipitated from 800 ml of methanol with addition of 20 mg of BHT each time.
[0118] Yield 18.5%
[0119] Mn=89 600 g/mol, Mw=237 000 g/mol
[0120] T.sub.g=178° C.
Example A3 Preparation of Polymer 3
[0121] Using a syringe technique, 10 ml of freshly distilled dicyclopentenyloxyethyl methacrylate (FA-512M, Hitachi Chemical), 10 ml of freshly distilled methyl methacrylate and 40 ml of THF were transferred under argon into a two-necked flask. Then 30 mg of 2,2′-azobisisobutyronitrile in the form of a THF solution were added, and the mixture was heated to 50° C. with stirring. After eight hours, the reaction was discontinued by addition of 50 mg of BHT and cooling to room temperature. The polymerization solution was precipitated from 1000 ml of methanol, and the polymer was isolated by filtration and dried under reduced pressure. The polymer was then dissolved again three times in 100 ml of THF and precipitated from 800 ml of methanol with addition of 20 mg of BHT each time.
[0122] Yield 35%
[0123] Mn=87 700 g/mol, Mw=317 000 g/mol
[0124] T.sub.g=94° C.
[0125] Repeating units in the polymer: FA-512M/MMA ratio 28:72 (determined via .sup.1H-NMR)
Example A4 Preparation of Polymer 4
[0126] 9 g of 5-methacryloyloxy-2,6-norbornanecarbolactone (NLAM, Kuraray) and also, using a syringe technique, 10 ml of freshly distilled dicyclopentenyloxyethyl methacrylate (FA-512M, Hitachi Chemical), and 40 ml of THF were transferred under argon into a two-necked flask. Then 30 mg of 2,2′-azobisisobutyronitrile in the form of a THF solution were added, and the mixture was heated to 50° C. with stirring. After eight hours, the reaction was discontinued by addition of 50 mg of BHT and cooling to room temperature. The polymerization solution was precipitated from 1000 ml of methanol, and the polymer was isolated by filtration and dried under reduced pressure. The polymer was then dissolved again three times in 100 ml of THF and precipitated from 800 ml of methanol with addition of 20 mg of BHT each time.
[0127] Yield 15.3%
[0128] Mn=55 200 g/mol, Mw=158 000 g/mol
[0129] T.sub.g=143° C.
[0130] Repeating units in the polymer: FA-512M/NLAM ratio 48:52 (determined via .sup.1H-NMR)
Example A5 Preparation of Polymer 5
[0131] Using a syringe technique, 10 ml of freshly distilled dicyclopentenyloxyethyl methacrylate (FA-512M, Hitachi Chemical), 1.5 ml of freshly distilled octafluoropentyl methacrylate (OFPMA) and 40 ml of THF were transferred under argon into a two-necked flask. Then 30 mg of 2,2′-azobisisobutyronitrile in the form of a THF solution were added, and the mixture was heated to 50° C. with stirring. After eight hours, the reaction was discontinued by addition of 50 mg of BHT and cooling to room temperature. The polymerization solution was precipitated from 1000 ml of methanol, and the polymer was isolated by filtration and dried under reduced pressure. The polymer was then dissolved again three times in 100 ml of THF and precipitated from 800 ml of methanol with addition of 20 mg of BHT each time.
[0132] Yield 19.8%
[0133] Mn=71 800 g/mol, Mw=201 000 g/mol
[0134] T.sub.g=64° C.
[0135] Repeating units in the polymer: FA-512M/OFPMA ratio 80.5:19.5 (determined via .sup.1H-NMR)
Example A6 Preparation of Polymer 6
[0136] Using a syringe technique, 10 ml of freshly distilled dicyclopentenyl methacrylate (CD535, Sartomer), 0.8 ml of freshly distilled stearyl methacrylate (SMA) and 40 ml of THF were transferred under argon into a two-necked flask. Then 30 mg of 2,2′-azobisisobutyronitrile in the form of a THF solution were added, and the mixture was heated to 50° C. with stirring. After eight hours, the reaction was discontinued by addition of 50 mg of BHT and cooling to room temperature. The polymerization solution was precipitated from 1000 ml of methanol, and the polymer was isolated by filtration and dried under reduced pressure. The polymer was then dissolved again three times in 100 ml of THF and precipitated from 800 ml of methanol with addition of 20 mg of BHT each time.
[0137] Yield 16.3%
[0138] Mn=109 000 g/mol, Mw=319 000 g/mol
[0139] T.sub.g=128° C.
[0140] Repeating units in the polymer: CD535/SMA ratio 91:9 (determined via .sup.1H-NMR)
Example A7 Preparation of Polymer 7
[0141] In a single-necked flask, under nitrogen, 175 g of styrene-co-maleic anhydride (Xiran 28110, Polyscope, 28% MAn fraction, Mw=110 000) were dissolved in 450 ml of solvent naphtha. Then 75.11 g of hydroxydicyclopentadiene (Texmark) and 66.0 g of dicyclopentadiene were added and the reaction solution was stirred at 130° C. for four hours. Following addition of a further 230 ml of solvent naphtha, the reaction solution was stirred for a further four hours under reflux at 160° C. The batch was diluted additionally with 350 ml of xylene. The polymer solution was cooled to room temperature (RT) and 20 g of the solution was precipitated from 475 ml of isopropanol water. Following filtration and washing with 500 ml of isopropanol, the residue was dissolved twice in 25 ml of methyl ethyl ketone and precipitated from 500 ml of Shellsol D25.
[0142] Yield 86.4%
[0143] Mn=73 100 g/mol, Mw=211 000 g/mol
[0144] T.sub.g=147° C.
Example A8 Preparation of Polymer 8
[0145] In a first single-necked flask, 10.4 of polyvinylbenzyl chloride (Sigma Aldrich 182532, Mn=43 300 & Mw=79 600) were dissolved in 250 ml of dried THF at room temperature under argon and with stirring. In a second single-necked flask, 9.4 ml of hydroxydicyclopentadiene were transferred under argon and 43 ml of butyllithium (1.6 molar) in hexane were added dropwise using a syringe technique with stirring. After a reaction time of five hours, the solvent was removed on a rotary evaporator and 80 ml of dried THF were added under argon. Using a syringe technique, the solution was subsequently added dropwise to the polymer solution in the first flask. After 48 hours the reaction was discontinued by precipitation from 1000 ml of isopropanol. The product was isolated by filtration and dried under reduced pressure. It was then dissolved again twice in 300 ml of THF and precipitated from 1000 ml of isopropanol.
[0146] Yield 41%
[0147] Mn=48 300 g/mol, Mw=116 000 g/mol
[0148] T.sub.g=89° C.
Example B1 Preparation of Photocrosslinked Dielectric Layers of Polymer 1-8
[0149] A polymer solution admixed with photoinitiator was filtered through a 0.45 μm PTFE syringe filter and applied by spin coating at 1000 rpm for 30 s to a 25×25 mm glass substrate. After heating of the coated substrate on a hotplate at 90° C. for 60 s, the film was exposed with a 365 nm LED lighting unit (LED Cube 100, Dr. Hönle). The UV dose varied from 300-1000 mJ/cm.sup.2 with a constant irradiation power of 100 mW/cm.sup.2. In order to evaluate the degree of insolubility of the photocrosslinked film, the substrate, after exposure, was immersed for 60 s in a solvent bath corresponding to the process solvent, and then the film retention was ascertained. The film retention was determined from the ratio of the layer thickness of the dry films after and before immersion in the solvent bath. The layer thickness was determined with the aid of a surface profilometer (Surface Profiler 150 Veeco) by scratching the film and determining the step height.
TABLE-US-00001 Photoinitiator content Process Polymer (weight fraction Film Polymer solvent concentration polymer) UV dose retention 1 MAK 120 mg/ml 2% OXE02 300 mJ/cm.sup.2 98% 1 MAK 120 mg/ml 6% ITX 500 mJ/cm.sup.2 94% 2 MAK 100 mg/ml 2% OXE02 300 mJ/cm.sup.2.sup.
Example B2 Preparation of a Photopatterned Layer of Polymer 1
[0150] A 120 mg/ml solution of polymer 1 with 2% of photoinitiator OXE02 (weight fraction polymer) in methyl amyl ketone (MAK) was applied by spin coating to a 25×25 mm glass substrate. The film was heated on a hotplate at 90° C. for 60 s and was subsequently subjected to imagewise UV exposure through a shadow mask (LED 365 nm, 300 mJ/cm.sup.2). Following immersion of the film for 60 s in a MAK solvent bath, the unexposed portion of the film was removed, leaving the imagewise-exposed, crosslinked portion.
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Example C1 Preparation of Capacitor Devices from Polymer 1-8
[0152] The substrate used was an indium tin oxide (ITO)-coated 25×25 mm glass, with the ITO layer (120 nm) serving as the back electrode. A 90-120 mg/ml polymer solution was filtered through a 0.45 μm PTFE syringe filter and applied to the substrate by spin coating at 1000 rpm for 30 s. Thereafter the substrate was heated on a hotplate at 90° C. for ten minutes. Finally, patterned counter-electrodes (50 nm) each with an area of 3 mm.sup.2 were applied by thermal evaporation of gold (HHV Auto 306) with the aid of a shadow mask.
[0153] The capacitor devices were characterized electrically using a Cascade Microtech MS 150 Probe Station and an Agilent E4980A LCR meter.
TABLE-US-00002 Process Polymer Layer Permittivity Loss factor Polymer solvent concentration thickness at 20 Hz at 20 Hz 1 MAK 110 mg/ml 525 nm 3.08 0.0063 2 MAK 100 mg/ml 520 nm 2.82 0.0013 3 MAK 110 mg/ml 510 nm 3.24 0.0181 4 CP:BuAc 1:1 90 mg/ml 485 nm 3.56 0.0098 5 MAK 120 mg/ml 580 nm 3.03 0.0082 6 MAK 110 mg/ml 595 nm 2.85 0.0088 7 PGMEA 100 mg/ml 620 nm 3.25 0.0091 8 MAK 100 mg/ml 535 nm 4.56 0.0268
Example C2 Preparation of a Top Gate OFET with Polymer 1 as Dielectric Layer
[0154] The substrate used was a PET film with prepatterned source and drain electrodes (40 nm gold) (acquired from Fraunhofer IPM, Freiburg). The channel length was 10 μm and the channel width was 10 mm. An 8 mg/ml solution of the semiconductor polymer PDPP2T-TT-OD (Sigma Aldrich 791989) in xylene was filtered through a 0.45 μm PTFE syringe filter and applied to the film by spin coating at 1000 rpm (30 s). The substrate was subsequently heated on a hotplate at 90° C. for 60 s. A 110 mg/ml solution of polymer 1 with 2% of photoinitiator OXE02 (weight fraction polymer) in MAK was filtered through a 0.45 μm PTFE syringe filter and applied to the film by spin coating at 1000 rpm (30 s). The coated substrate was prebaked on a hotplate at 90° C. for 60 s. The substrate was subjected to UV exposure (LED 365 nm, 300 mJ/cm.sup.2), followed by a postbake on a hotplate at 90° C. for 60 s. Subsequently the substrate was immersed for 60 s in a MAK bath, dried under a stream of nitrogen and heated on a hotplate at 90° C. for ten minutes. A patterned gate electrode (50 nm) was applied by thermal evaporation of gold (HHV Auto 306) using a shadow mask.
[0155] The transistor devices were characterized electrically using a Cascade Microtech MS 150 Probe Station and a Keithley 2612A SMU.
[0156]
Example C3 Preparation of a Bottom Gate OFET with Polymer 6 as Dielectric Layer
[0157] The substrate used was an ITO-coated glass substrate, with the ITO layer serving as gate electrode. A 110 mg/ml solution of polymer 6 with 2% of OXE02 (weight fraction polymer) in MAK was filtered through a 0.45 μm PTFE syringe filter and applied to the ITO substrate by spin coating at 1000 rpm for 30 s. The coated substrate was prebaked on a hotplate at 90° C. for 60 s. Thereafter the substrate was subjected to UV exposure (LED 365 nm, 300 mJ/cm.sup.2), followed by a postbake on a hotplate at 90° C. for 60 s. The substrate was subsequently immersed in a MAK bath for 60 s, dried under a stream of nitrogen and heated on a hotplate at 90° C. for ten minutes. The patterned source and drain electrodes (30 nm) were applied by thermal evaporation of gold (HHV Auto 306) with the aid of a shadow mask. The channel length was 100 μm and the channel width was 4 mm. An 8 mg/ml solution of the semiconductor polymer PDPP2T-TT-OD (Sigma Aldrich 791989) in xylene was filtered through a 0.45 μm PTFE syringe filter and applied to the substrate by spin coating at 1000 rpm (30 s). Lastly the substrate was heated on a hotplate at 90° C. for ten minutes.
[0158] The transistor devices were characterized electrically using a Cascade Microtech MS 150 Probe Station and a Keithley 2612A SMU.
[0159]
Example C4 Preparation of a Top Gate OFET with Polymer 7 as Dielectric Layer
[0160] The substrate used was a PET film with prepatterned source and drain electrodes (40 nm gold) (acquired from Fraunhofer IPM, Freiburg). The channel length was 10 μm and the channel width was 10 mm. An 8 mg/ml solution of the semiconductor polymer PDPP2T-TT-OD (Sigma Aldrich 791989) in xylene was filtered through a 0.45 μm PTFE syringe filter and applied to the film by spin coating at 1000 rpm (30 s). The substrate was subsequently heated on a hotplate at 90° C. for 60 s. A 110 mg/ml solution of polymer 7 with 8% of photoinitiator OXE02 (weight fraction polymer) in PGMEA was filtered through a 0.45 μm PTFE syringe filter and applied to the film by spin coating at 1000 rpm (30 s). The coated substrate was prebaked on a hotplate at 90° C. for 60 s. The substrate was subjected to UV exposure (LED 365 nm, 1000 mJ/cm.sup.2), followed by a postbake on a hotplate at 90° C. for 60 s. Subsequently the substrate was immersed for 60 s in a MAK bath, dried under a stream of nitrogen and heated on a hotplate at 90° C. for ten minutes. A patterned gate electrode (50 nm) was applied by thermal evaporation of gold (HHV Auto 306) using a shadow mask.
[0161] The transistor devices were characterized electrically using a Cascade Microtech MS 150 Probe Station and a Keithley 2612A SMU.
[0162]
Example C5 Preparation of a Bottom Gate OFET with Polymer 7 as Dielectric Layer
[0163] The substrate used was an ITO-coated glass substrate, with the ITO layer serving as gate electrode. A 110 mg/ml solution of polymer 7 with 8% of OXE02 (weight fraction polymer) in MAK was filtered through a 0.45 μm PTFE syringe filter and applied to the ITO substrate by spin coating at 1000 rpm for 30 s. The coated substrate was prebaked on a hotplate at 90° C. for 60 s. Thereafter the substrate was subjected to UV exposure (LED 365 nm, 1000 mJ/cm.sup.2), followed by a postbake on a hotplate at 90° C. for 60 s. The substrate was subsequently immersed in a MAK bath for 60 s, dried under a stream of nitrogen and heated on a hotplate at 90° C. for ten minutes. The patterned source and drain electrodes (30 nm) were applied by thermal evaporation of gold (HHV Auto 306) with the aid of a shadow mask. The channel length was 100 μm and the channel width was 4 mm. An 8 mg/ml solution of the semiconductor polymer PDPP2T-TT-OD (Sigma Aldrich 791989) in xylene was filtered through a 0.45 μm PTFE syringe filter and applied to the film by spin coating at 1000 rpm (30 s). Lastly the substrate was heated on a hotplate at 90° C. for ten minutes.
[0164] The transistor devices were characterized electrically using a Cascade Microtech MS 150 Probe Station and a Keithley 2612A SMU.
[0165]