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CN-121995693-A - Composition for directed self-assembly and method of patterning

CN121995693ACN 121995693 ACN121995693 ACN 121995693ACN-121995693-A

Abstract

Embodiments of the present disclosure relate to a composition for directed self-assembly and a patterning method, the directed self-assembled composition including a block copolymer, a photoacid generator, and a solvent, by forming a composition composed of the block copolymer, the photoacid generator, and the solvent, since an acetal bond that can be acid-cleaved between a first homopolymer and a second homopolymer forming the block copolymer is formed, the block copolymer obtained by reacting the first homopolymer with the second homopolymer can be decomposed with high efficiency under an exposure condition by the action of the photoacid generator.

Inventors

  • LIU JIE
  • SUN DIANMING
  • LIU ZHONGMING

Assignees

  • 长鑫科技集团股份有限公司

Dates

Publication Date
20260508
Application Date
20241107

Claims (10)

  1. 1. A composition for directed self-assembly comprising a block copolymer having the structural formula (1), Wherein R 1 to R 7 are each independently selected from hydrogen, halogen, saturated or unsaturated C1 to C4 alkyl, C-1 to C10 fluoroalkyl groups or (trialkylsilyl) alkenyl groups; Photoacid generators and solvents.
  2. 2. The composition of claim 1, wherein the block copolymer is obtained by reacting a first homopolymer of formula (2) with a second homopolymer of formula (3), Wherein R comprises R6 or R7.
  3. 3. The composition of claim 2, wherein the step of reacting the first homopolymer with the second homopolymer to obtain the block copolymer comprises: the first homopolymer and the second homopolymer are jointly dissolved in tetrahydrofuran solution, and aldol condensation reaction is carried out under the action of a catalyst to generate the block copolymer; And dissolving the photoacid generator and the block copolymer generated by the reaction in the solvent to obtain the composition.
  4. 4. A composition according to claim 3, wherein the catalyst is an organic or inorganic base.
  5. 5. The composition of claim 2, wherein the molar ratio of the first homopolymer to the second homopolymer is in the range of 1:1 to 1:3.
  6. 6. The composition of claim 2, wherein the first homopolymer has a weight average molecular weight in the range of 1000-10000g/mol and the second homopolymer has a weight average molecular weight in the range of 3000-6000g/mol.
  7. 7. The composition according to claim 2, wherein the mass percentage of the block copolymer in the composition ranges from 5% to 30%, the mass percentage of the solvent in the composition ranges from 70% to 95%, and the mass percentage of the photoacid generator in the composition is less than 1%.
  8. 8. The composition of claim 1, wherein the solvent comprises an ester or ketone compound.
  9. 9. A method for directional self-assembled patterning, comprising: Providing a substrate; forming an anti-reflection layer and a neutral layer on the surface of the substrate; forming a composition layer consisting of the composition of any one of claims 1 to 8 on the neutral layer; exposing the composition layer to light to cause self-assembly of the composition layer to form an array structure of the first homopolymer layer and the second homopolymer layer; and removing the second homopolymer layer in the array structure to form a target pattern.
  10. 10. The method of claim 9, wherein exposing the composition layer to light causes self-assembly of the composition layer to form an array structure of the first homopolymer layer and the second homopolymer layer and removing the second homopolymer layer from the array structure to form the target pattern, comprising: The exposure light source is ultraviolet light, the photoacid generator in the composition generates acidolysis under the irradiation of the ultraviolet light to generate acid so as to decompose the block copolymer in the composition into the first homopolymer and the second homopolymer, the decomposed first homopolymer forms the first homopolymer layer, and the decomposed second homopolymer forms the second homopolymer layer; And removing the second homopolymer layer and the wet etching solution by wet etching to form the target pattern, wherein the etching selectivity ratio of the second homopolymer to the first homopolymer is greater than 95:1.

Description

Composition for directed self-assembly and method of patterning Technical Field Embodiments of the present disclosure relate to the field of semiconductors, and more particularly, to a composition for directed self-assembly and a method of patterning. Background The technology of forming a pattern conversion template by microphase separation between different blocks to manufacture a related semiconductor device is adopted by a block copolymer obtained by polymerizing two or more monomers with different chemical properties by utilizing a block copolymer directed self-assembly technology (DIRECTED SELF-assembly, DSA). Compared with the traditional photoetching technology, the DSA technology using the block copolymer does not need a light source and a mask plate, can obtain a large-scale ordered pattern, and has the advantages of low cost, high resolution, high productivity and the like. Conventional DSA materials still suffer from a number of disadvantages, such as the tendency to over-etch or under-etch when etching to remove the monomeric polymer in the block copolymer, resulting in higher pattern defect rates. Therefore, there is a need to develop a novel block copolymer material to improve the patterning quality. Disclosure of Invention According to some embodiments of the present disclosure, an aspect of the present disclosure provides a composition for directed self-assembly comprising a block copolymer having the structural formula (1), Wherein R1 to R7 are each independently selected from hydrogen, halogen, saturated or unsaturated C1 to C4 alkyl, C-1 to C10 fluoroalkyl groups or (trialkylsilyl) alkenyl groups; Photoacid generators and solvents. In some embodiments, the block copolymer is composed of a first homopolymer of formula (2) and a second homopolymer of formula (3) The second homopolymer is obtained by a reaction of a second homopolymer, Wherein R comprises R6 or R7. In some embodiments, the step of reacting the first homopolymer and the second homopolymer to obtain the block copolymer comprises dissolving the first homopolymer and the second homopolymer together in a tetrahydrofuran solution and performing an aldol condensation reaction under the action of a catalyst to generate the block copolymer, and dissolving the photoacid generator and the block copolymer generated by the reaction in the solvent to obtain the composition. In some embodiments, the catalyst is an organic base or an inorganic base. In some embodiments, the molar ratio of the first homopolymer to the second homopolymer ranges from 1:1 to 1:3. In some embodiments, the first homopolymer has a weight average molecular weight in the range of 1000 to 10000g/mol and the second homopolymer has a weight average molecular weight in the range of 3000 to 6000g/mol. In some embodiments, the block copolymer is present in the composition in a range of 5% to 30% by mass, the solvent is present in the composition in a range of 70% to 95% by mass, and the photoacid generator is present in the composition in a range of less than 1% by mass. In some embodiments, the solvent comprises an ester or ketone compound. According to some embodiments of the present disclosure, there is also provided, in another aspect, a method for directional self-assembled patterning, including: providing a substrate, forming an anti-reflection layer and a neutral layer on the surface of the substrate, forming a composition layer composed of the composition on the neutral layer, exposing the composition layer to light to enable the composition layer to self-assemble to form an array structure composed of the first homopolymer layer and the second homopolymer layer, and removing the second homopolymer layer in the array structure to form a target pattern. In some embodiments, exposing the composition layer to light to self-assemble the composition layer to form an array structure comprising the first homopolymer layer and the second homopolymer layer, and removing the second homopolymer layer from the array structure to form the target pattern, wherein the exposure light source is ultraviolet light, the photoacid generator in the composition is subjected to acidolysis under the irradiation of the ultraviolet light to generate acid so that the block copolymer in the composition is decomposed into the first homopolymer and the second homopolymer, the first homopolymer after decomposition forms the first homopolymer layer, the second homopolymer after decomposition forms the second homopolymer layer, and the second homopolymer layer and the wet etching solution are removed by wet etching to form the target pattern, wherein the etching selectivity ratio of the second homopolymer to the first homopolymer is greater than 95:1. According to the embodiments of the present disclosure, by forming a composition composed of a block copolymer having the structural formula (1), a photoacid generator, and a solvent, since the first homopolymer and the second homopolymer are bonded