EXPANSION POLYMERIZATION IMPRINTING GLUE FOR NANO-PRINTING

Abstract

An expansion polymerization imprinting glue for nano-imprinting. Raw materials required for the preparation of the expansion polymerization imprinting glue comprise a low polymer and an expansion monomer. Compared with the prior art, after the expansion monomer is introduced into the expansion polymerization imprinting glue for nano-imprinting, the expansion monomer can be polymerized with the low polymer, the volume change of the imprinting glue after polymerization can be adjusted, and accordingly the volume shrinkage after the imprinting glue is cured is reduced or even eliminated; and the imprinting glue having zero curing shrinkage or volume expansion can be obtained by adjusting the content of the expansion monomer. The imprinting glue can effectively reduce the residual stress in a micro-nano pattern, and the generation of pattern defects in the nano-imprinting demolding process caused by the residual stress is reduced while accurate pattern copying is implemented.

Claims

1. An expansion polymerization imprint resist for nano-imprinting, raw materials required for the preparation of which comprise an oligomer, wherein the raw materials further comprise an expansion monomer.

2. The expansion polymerization imprint resist for nano-imprinting according to claim 1, wherein the expansion monomer accounts for 10-200% of the weight of the oligomer.

3. The expansion polymerization imprint resist for nano-imprinting according to claim 1, wherein the expansion monomer is one selected from the group consisting of spiro orthoester compound, spiro orthocarbonate compound, bicyclic orthoester compound and bicyclic lactone compound, or a mixture of at least two thereof.

4. The expansion polymerization imprint resist for nano-imprinting according to claim 3, wherein the spiro orthoester compound is selected from the spiro orthoester monomer represented by formula I or derivatives thereof, the unsaturated spiro orthoester monomer represented by formula II or derivatives thereof; ##STR00015## in formula I, R=(CH.sub.2).sub.n, n=2, 3 or 4; R.sub.1=hydrogen, alkyl, haloalkyl, phenyl, anisyl or o-methyl anisyl; in formula II, R=(CH.sub.2).sub.n, n=2, 3 or 4.

5. The expansion polymerization imprint resist for nano-imprinting according to claim 3, wherein the spiro orthocarbonate compound is selected from the spiro orthocarbonate monomer represented by formula III or derivatives thereof, an unsaturated spiro orthocarbonate monomer or derivatives thereof; ##STR00016## in formula III, R=(CH.sub.2).sub.n, n=1, 2, 3, 4; R.sub.1=(CH.sub.2).sub.n, n=1, 2, 3, 4.

6. The expansion polymerization imprint resist for nano-imprinting according to claim 3, wherein the bicyclic orthoester compound comprises a bicyclic orthoester monomer represented by formula IV and derivatives thereof; ##STR00017## in formula IV, R=(CH.sub.2).sub.n, n=0 or 1; R.sub.1=hydrogen, alkyl, haloalkyl, phenyl, alkylhydroxyl, nitro, amine or ester group; R.sub.2=hydrogen, alkyl, haloalkyl, phenyl, halophenyl, tolyl or methoxyphenyl.

7. The expansion polymerization imprint resist for nano-imprinting according to claim 3, wherein the bicyclic lactone compound is a bicyclic lactone monomer represented by formula V; ##STR00018##

8. The expansion polymerization imprint resist for nano-imprinting according to claim 1, wherein the raw materials further comprise a photoinitiator, which accounts for 0.1-5% of the total weight of the oligomer and the expansion monomer.

9. The expansion polymerization imprint resist for nano-imprinting according to claim 1, wherein the raw materials further comprise a diluent, which is added at such an amount that the viscosity of the imprint resist is allowed to be 1-10000 cP.

10. The expansion polymerization imprint resist for nano-imprinting according to claim 1, wherein the oligomer is an epoxy resin oligomer;

11. The expansion polymerization imprint resist for nano-imprinting according to claim 4, wherein the derivatives of the spiro orthoester monomer are selected from at least one of the followings: ##STR00019##

12. The expansion polymerization imprint resist for nano-imprinting according to claim 5, wherein the derivatives of the spiro orthocarbonate monomer are selected from at least one of the followings: ##STR00020##

13. The expansion polymerization imprint resist for nano-imprinting according to claim 5, wherein the unsaturated spiro orthocarbonate monomer and derivatives thereof are selected from at least one of the followings: ##STR00021##

14. The expansion polymerization imprint resist for nano-imprinting according to claim 6, wherein the derivatives of the bicyclic orthoester monomer are selected from the followings: ##STR00022##

15. The expansion polymerization imprint resist for nano-imprinting according to claim 8, wherein the photoinitiator is a cationic photoinitiator.

16. The expansion polymerization imprint resist for nano-imprinting according to claim 8, wherein the photoinitiator is one selected from the group consisting of aryldiazonium salt, diaryliodonium salt, triarylsulfonium salt and aryl ferrocenium salt, or a mixture of at least two thereof.

17. The expansion polymerization imprint resist for nano-imprinting according to claim 1, wherein the raw materials for preparing the expansion polymerization imprint resist for nano-imprinting further comprise a cross-linking agent.

18. The expansion polymerization imprint resist for nano-imprinting according to claim 17, wherein the cross-linking agent contains at least one epoxy group.

19. The expansion polymerization imprint resist for nano-imprinting according to claim 1, wherein the raw materials for preparing the expansion polymerization imprint resist for nano-imprinting further comprise a demolding agent.

20. The expansion polymerization imprint resist for nano-imprinting according to claim 1, wherein the expansion polymerization imprint resist for nano-imprinting further comprises one selected from the group consisting of a defoaming agent, a leveling agent, a dispersing agent, a matting agent and a polymerization inhibitor, or a combination of at least two thereof.

Description

DESCRIPTION OF THE DRAWINGS

[0036] FIG. 1 is a microscope image of an imprint pattern obtained according to Example 2 of the present invention;

[0037] FIG. 2 is an atomic force microscope image (i.e. an AFM image) of an imprint pattern obtained according to Example 2 of the present invention.

DETAILED DESCRIPTION

[0038] The present invention will be further described in detail with reference to the examples and the accompanying drawings.

Example 1: A Mixed Imprint Resist System of Spiro Orthocarbonate and Epoxy Resin

[0039] Raw materials required for the preparation of the expansion polymerization imprint resist for nano-imprinting in this example comprise an oligomer, an expansion monomer and a photoinitiator, wherein the oligomer is an epoxy resin monomer, the expansion monomer is a spiro orthocarbonate compound, specifically is 2,4,8,10-tetramethyl-1,5,7,11-tetraoxaspiro[5,5]undecane having a structure as shown in formula VI, and the photoinitiator is triaryliodonium salt.

##STR00009##

[0040] The preparation process of the expansion polymerization imprint resist for nano-imprinting of the present example is as following: the epoxy resin oligomer, the expansion monomer 2,4,8,10-tetramethyl-1,5,7,11-tetraoxaspiro[5,5]undecane and the triaryliodonium salt photoinitiator were uniformly mixed when avoiding light. The weight percentage of the oligomer, expansion monomer and photoinitiator were 90 wt %, 9 wt % and 1 wt %, respectively. In the present example, 2,4,8,10-tetramethyl-1,5,7,11-tetraoxyspiro[5,5]undecane was prepared by using the reaction of di-n-butyl tin ester and carbon disulfide. Besides this method, three other methods, i.e. the transesterification reaction, the reaction of alkoxy thallium compound and carbon disulfide and the reaction of sodium diol and nitromethane can be used.

[0041] The imprint resist as described above was dropped on a substrate. The contact angle of the imprint resist liquid droplets and the substrate was measured by using a contact angle measuring instrument, and the contact angle was converted to the volume of the liquid droplet, designated as V.sub.1. The imprint resist liquid droplets as described above were exposed to UV light. The contact angle was measured by a contact angle measuring instrument after curing, and converted to volume, designated as V.sub.s. The shrinkage rate, (V.sub.1V.sub.s)/V1, was 1.6%, which decreased by 55% compared with the shrinkage when no expansion monomer was added.

Example 2: A Mixed Imprint Resist System of Spiro Orthocarbonate and Silicon-Containing Epoxy Resin

[0042] Raw materials required for the preparation of the expansion polymerization imprint resist for nano-imprinting in this example comprise an oligomer, an expansion monomer, a photoinitiator and a diluent, wherein the oligomer is a silicon-containing epoxy resin monomer, the expansion monomer is a spiro orthocarbonate compound, specifically is 1,5,7,11-tetraoxaspiro[5,5]undecane having a structure as shown in formula VII, the photoinitiator is triaryliodonium salt, and the diluent is PGMEA.

##STR00010##

[0043] The preparation process of the expansion polymerization imprint resist for nano-imprinting of the present example is as following: the silicon-containing epoxy resin oligomer, the expansion monomer 1,5,7,11-tetraoxaspiro[5,5]undecane, the photoinitiator and the diluent PGMEA were uniformly mixed when avoiding light. The weight percentage of the oligomer, expansion monomer, photoinitiator and diluent were 20 wt %, 19 wt %, 1 wt % and 60 wt %, respectively. In the present example, 1,5,7,11-tetraoxyspiro[5,5]undecane was prepared by using the transesterification reaction. Besides this method, three other methods, i.e. the reaction of tri-n-butyl tin ester and carbon disulfide, the reaction of alkoxy thallium compound and carbon disulfide and the reaction of sodium diol and nitromethane can be used.

[0044] The imprint resist as described above was dropped on a substrate. The contact angle of the imprint resist liquid droplets and the substrate was measured by using a contact angle measuring instrument, and the contact angle was converted to the volume of the liquid droplet, designated as V.sub.1. The imprint resist liquid droplets as described above were exposed to UV light. The contact angle was measured by a contact angle measuring instrument after curing, and converted to volume, designated as V.sub.s. The shrinkage rate, (V.sub.1V.sub.s)/V.sub.1, was 0.

[0045] Before the imprint resist was spin-coated, a polymer film which was not soluble in PGMEA was firstly spin-coated on the substrate and then the imprint resist was spin-coated. The pre-spin coating of polymer thin film can prevent the imprint glue from wetting, which facilitate obtaining a uniform imprint glue thin film. Meanwhile, the polymer film can be used as an intermediate layer in pattern transferring. After removing the diluent by soft baking the liquid thin film, the imprinting was performed at room temperature under low pressure, and the film was exposed to UV at a wavelength of 365 nm. Five minutes later, the template was separated from the imprint resist to obtain a complete imprint pattern with imprint lines having a cycle width of 20 m and a raised width of 15 The surface morphology of the imprint pattern was observed by using a microscope and an AFM at a magnification of 50 times, as shown in FIG. 1 and FIG. 2, respectively.

Example 3: A Mixed Imprint Resist System of Spiro Orthocarbonate and Silicon-Containing Epoxy Resin

[0046] Raw materials required for the preparation of the expansion polymerization imprint resist for nano-imprinting in this example comprise an oligomer, an expansion monomer, a photoinitiator and a diluent, wherein the oligomer is a silicon-containing epoxy resin monomer, the expansion monomer is a spiro orthocarbonate compound, specifically is 1,5,7,11-tetraoxaspiro[5,5]undecane having a structure as shown in formula VII, the photoinitiator is triaryliodonium salt, and the diluent is epoxy cationic active diluent.

[0047] The preparation process of the expansion polymerization imprint resist for nano-imprinting of the present example is as following: the silicon-containing epoxy resin oligomer, the expansion monomer 1,5,7,11-tetraoxaspiro[5,5]undecane, the photoinitiator and the diluent were uniformly mixed when avoiding light. The weight percentage of the oligomer, expansion monomer, photoinitiator and diluent were 20 wt %, 35 wt %, 1 wt % and 44 wt %, respectively. In the present example, 1,5,7,11-tetraoxyspiro[5,5]undecane was prepared by using the transesterification reaction. Besides this method, three other methods, i.e. the reaction of tri-n-butyl tin ester and carbon disulfide, the reaction of alkoxy thallium compound and carbon disulfide and the reaction of sodium diol and nitromethane can be used.

[0048] The imprint resist as described above was dropped on a substrate. The contact angle of the imprint resist liquid droplets and the substrate was measured by using a contact angle measuring instrument, and the contact angle was converted to the volume of the liquid droplet, designated as V.sub.1. The imprint resist liquid droplets as described above were exposed to UV light. The contact angle was measured by a contact angle measuring instrument after curing, and converted to volume, designated as V.sub.s. The shrinkage rate, (V.sub.1V.sub.s)/V.sub.1, was 1%, which decreased by 70% compared with the shrinkage when no expansion monomer was added.

Example 4: A Mixed Imprint Resist System of Spiro Orthocarbonate and Silicon-Containing Epoxy Resin

[0049] Raw materials required for the preparation of the expansion polymerization imprint resist for nano-imprinting in this example comprise an oligomer, an expansion monomer, a photoinitiator, a cross-linking agent and a diluent, wherein the oligomer is a silicon-containing epoxy resin monomer, the expansion monomer is a spiro orthocarbonate compound, specifically is 1,4,6,9-tetraoxaspiro[4,4]nonane having a structure as shown in formula VIII, the photoinitiator is triaryliodonium salt, the cross-linking agent is silicon-containing epoxy resin monomer containing four epoxy groups and the diluent is PGMEA.

##STR00011##

[0050] The preparation process of the expansion polymerization imprint resist for nano-imprinting of the present example is as following: the silicon-containing epoxy resin oligomer, the expansion monomer 1,4,6,9-tetraoxaspiro[4,4]nonane, the triaryliodonium salt photoinitiator, the cross-linking agent and the diluent were uniformly mixed when avoiding light. The weight percentage of the oligomer, expansion monomer, photoinitiator, cross-linking agent and diluent were 12 wt %, 22 wt %, 1 wt %, 5 wt % and 60% respectively. In the present example, 1,4,6,9-tetraoxaspiro[4,4]nonane was prepared by using the reaction of di-n-butyl tin ester and carbon disulfide. Besides this method, three other methods, i.e. the transesterification reaction, the reaction of alkoxy thallium compound and carbon disulfide and the reaction of sodium diol and nitromethane can be used.

[0051] The imprint resist as described above was dropped on a substrate. The contact angle of the imprint resist liquid droplets and the substrate was measured by using a contact angle measuring instrument, and the contact angle was converted to the volume of the liquid droplet, designated as V.sub.1. The imprint resist liquid droplets as described above were exposed to UV light. The contact angle was measured by a contact angle measuring instrument after curing, and converted to volume, designated as V.sub.s. The shrinkage rate, (V.sub.1V.sub.s)/V.sub.1, was 1.5%, which decreased by 57% compared with the shrinkage when no expansion monomer was added.

Example 5: A Mixed Imprint Resist System of Spiro Orthoester and Silicon-Containing Epoxy Resin

[0052] Raw materials required for the preparation of the expansion polymerization imprint resist for nano-imprinting in this example comprise an oligomer, an expansion monomer, a photoinitiator, a cross-linking agent and a diluent, wherein the oligomer is a silicon-containing epoxy resin monomer, the expansion monomer is a spiro orthoester compound, specifically is 1,4,6-trioxaspiro[4,4]nonane having a structure as shown in formula IX, the photoinitiator is triaryliodonium salt, the cross-linking agent is silicon-containing epoxy resin monomer containing four epoxy groups and the diluent is PGMEA.

##STR00012##

[0053] The preparation process of the expansion polymerization imprint resist for nano-imprinting of the present example is as following: the silicon-containing epoxy resin oligomer, the expansion monomer 1,4,6-trioxaspiro[4,4]nonane, the triaryliodonium salt photoinitiator, the cross-linking agent and the diluent were uniformly mixed when avoiding light. The weight percentage of the oligomer, expansion monomer, photoinitiator, cross-linking agent and diluent were 17 wt %, 17 wt %, 1 wt %, 5 wt % and 60% respectively. In the present example, 1,4,6-trioxaspiro[4,4]nonane was prepared by using the reaction of lactone and oxidized alkylene. Besides this method, an addition reaction of unsaturated acetal can also be used.

[0054] The imprint resist as described above was dropped on a substrate. The contact angle of the imprint resist liquid droplets and the substrate was measured by using a contact angle measuring instrument, and the contact angle was converted to the volume of the liquid droplet, designated as V.sub.1. The imprint resist liquid droplets as described above were exposed to UV light. The contact angle was measured by a contact angle measuring instrument after curing, and converted to volume, designated as V.sub.s. The shrinkage rate, (V.sub.1V.sub.s)/V.sub.1, was 1.8%, which decreased by 49% compared with the shrinkage when no expansion monomer was added.

Example 6: A Mixed Imprint Resist System of Bicyclic Orthoester and Silicon-Containing Epoxy Resin

[0055] Raw materials required for the preparation of the expansion polymerization imprint resist for nano-imprinting in this example comprise an oligomer, an expansion monomer, a photoinitiator, a cross-linking agent and a diluent, wherein the oligomer is a silicon-containing epoxy resin monomer, the expansion monomer is a bicyclic orthoester compound, specifically is 2,6,7-trioxaspiro[2,2,1]heptane having a structure as shown in formula X, the photoinitiator is diaryliodonium salt, the cross-linking agent is silicon-containing epoxy resin monomer containing four epoxy groups and the diluent is PGMEA.

##STR00013##

[0056] The preparation process of the expansion polymerization imprint resist for nano-imprinting of the present example is as following: the silicon-containing epoxy resin oligomer, the expansion monomer 2,6,7-trioxaspiro[2,2,1]heptane, the diaryliodonium salt photoinitiator, the cross-linking agent and the diluent were uniformly mixed when avoiding light. The weight percentage of the oligomer, expansion monomer, photoinitiator, cross-linking agent and diluent were 22 wt %, 22 wt %, 1 wt %, 5 wt % and 50% respectively. In the present example, 2,6,7-trioxaspiro[2,2,1]heptane was prepared by using the exchange reaction of orthoester and triol.

[0057] The imprint resist as described above was dropped on a substrate. The contact angle of the imprint resist liquid droplets and the substrate was measured by using a contact angle measuring instrument, and the contact angle was converted to the volume of the liquid droplet, designated as V.sub.1. The imprint resist liquid droplets as described above were exposed to UV light. The contact angle was measured by a contact angle measuring instrument after curing, and converted to volume, designated as V.sub.s. The shrinkage rate, (V.sub.1V.sub.s)/V.sub.1, was 2.1%, which decreased by 40% compared with the shrinkage when no expansion monomer was added.

Example 7: A Mixed Imprint Resist System of Bicyclic Lactone and Silicon-Containing Epoxy Resin

[0058] Raw materials required for the preparation of the expansion polymerization imprint resist for nano-imprinting in this example comprise an oligomer, an expansion monomer, a photoinitiator and a diluent, wherein the oligomer is a silicon-containing epoxy resin monomer, the expansion monomer is a bicyclic lactone having a structure as shown in formula XI, the photoinitiator is triaryliodonium salt and the diluent is PGMEA.

##STR00014##

[0059] The preparation process of the expansion polymerization imprint resist for nano-imprinting of the present example is as following: the silicon-containing epoxy resin oligomer, the bicyclic lactone expansion monomer, the photoinitiator and the diluent were uniformly mixed when avoiding light. The weight percentage of the oligomer, expansion monomer, photoinitiator and diluent were 24 wt %, 25 wt %, 1 wt % and 50% respectively.

[0060] The imprint resist as described above was dropped on a substrate. The contact angle of the imprint resist liquid droplets and the substrate was measured by using a contact angle measuring instrument, and the contact angle was converted to the volume of the liquid droplet, designated as V.sub.1. The imprint resist liquid droplets as described above were exposed to UV light. The contact angle was measured by a contact angle measuring instrument after curing, and converted to volume, designated as V.sub.s. The shrinkage rate, (V.sub.1V.sub.s)/V.sub.1, was 2.5%, which decreased by 28% compared with the shrinkage when no expansion monomer was added.

[0061] The above contents are only preferred examples of the present invention, and those skilled in the art may make modifications to the specific embodiments and application scope according to the concept of the present invention, and the contents of the specification should not be construed as a limitation to the present invention.