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US-12619148-B2 - Crosslinkable photoresist for extreme ultraviolet lithography

US12619148B2US 12619148 B2US12619148 B2US 12619148B2US-12619148-B2

Abstract

A method for forming a semiconductor device includes forming a photoresist layer over a substrate, exposing the photoresist layer to radiation to form a pattern therein, and selectively removing portions of the photoresist layer that are not exposed to the radiation to form a patterned photoresist layer. The photoresist layer comprises a fluorine-containing polymer, a crosslinker and a photoactive compound.

Inventors

  • Li-Po YANG
  • Wei-Han Lai
  • Ching-Yu Chang

Assignees

  • TAIWAN SEMICONDUCTOR MANUFACTURING CO., LTD.

Dates

Publication Date
20260505
Application Date
20220502

Claims (20)

  1. 1 . A method of forming a semiconductor device, comprising: forming a photoresist layer over a substrate, wherein the photoresist layer comprises a polymer, a crosslinker and a photoactive compound; exposing the photoresist layer to radiation to form a pattern therein; and selectively removing portions of the photoresist layer that are not exposed to the radiation to form a patterned photoresist layer, wherein the polymer has the following structure (I): wherein: L 1 , L 2 and L 3 are, at each occurrence, independently a direct bond or a linker selected from oxy, carbonyl, carbonyloxy, oxycarbonyl, carbonate, halogenated or non-halogenated alkylene, halogenated or non-halogenated cycloalkylene, halogenated or non-halogenated oxyalkylene, halogenated or non-halogenated oxycycloalkylene, halogenated or non-halogenated carbonyloxyalkylene, halogenated or non-halogenated heteroalkylene, or halogenated or non-halogenated cycloheteroalkylene; Ar 1 is, at each occurrence, independently halogenated or non-halogenated arylene or halogenated or non-halogenated heteroarylene; Q is, at occurrence, independently an acid labile group; X 1 and X 2 are, at each occurrence, independently a reactive group, or protected form thereof, capable of forming a covalent bond with the crosslinker; R 1 , R 2 and R 3 are, at each occurrence, independently H, alkyl or alkoxy; and 0<x/(x+y+z)<1, 0≤y/(x+y+z)<1 and 0<z/(x+y+z)<1, provided that at least one of L 1 and L 2 is halogenated when y>0 and that L 1 is halogenated alkylene when y=0.
  2. 2 . The method of claim 1 , wherein the at least one of L 1 and L 2 is fluorinated.
  3. 3 . The method of claim 1 , wherein L 1 or L 3 , or both, is a direct bond, and L 2 is fluoroalkylene.
  4. 4 . The method of claim 1 , wherein L 1 , L 2 and L 3 are each independently a direct bond, carbonyloxy or fluoroalkylene.
  5. 5 . The method of claim 4 , wherein L 1 , L 2 and L 3 each independently have one of the following structures:
  6. 6 . The method of claim 1 , wherein Ar 1 has one of the following structures:
  7. 7 . The method of claim 1 , wherein Q is, at each occurrence, independently an alkyl group, a cycloalkyl group, a hydroxyalkyl group, an alkoxy group, an alkoxyalkyl group or a group having a three-dimensional (3D) ring structure.
  8. 8 . The method of claim 7 , wherein the 3D ring structure is adamantyl, cedryl, norbornyl or tricyclodecanyl.
  9. 9 . The method of claim 1 , wherein Q has one of the following structures:
  10. 10 . The method of claim 1 , wherein X 1 and X 2 are, at each occurrence, independently hydroxyl, alkoxy, amine, thiol, ester, melamine, alkene, alkyne, epoxy, aziridine, oxetane, aldehyde, ketone or a carboxylic acid.
  11. 11 . The method of claim 1 , wherein R 1 , R 2 and R 3 are each independently H or methyl.
  12. 12 . The method of claim 1 , wherein the polymer has one of the following structures:
  13. 13 . The method of claim 1 , wherein L 1 and L 2 are fluoroalkylene, and L 3 is a direct bond, wherein the polymer has the following structure (Ia): wherein: R 1 , R 2 and R 3 are, at each occurrence, independently H or alkyl; Rf 1 and Rf 2 are, at each occurrence, independently fluoroalkylene; Z 1 is, at each occurrence, independently F or fluoroalkyl; Q is, at each occurrence, independently an alkyl group, a cycloalkyl group, a hydroxyalkyl group, an alkoxy group, an alkoxyalkyl group, an adamantyl group, a cedryl group, a norbornyl group, or a tricyclodecanyl group; X 1 and X 2 are, at each occurrence, independently hydroxyl, epoxy, melamine, alkene, or alkyne; a 1 is, at each occurrence, an integer from 0 to 4; and 0<x/(x+y+z)<1, 0<y/(x+y+z)<1 and 0<z/(x+y+z)<1.
  14. 14 . The method of claim 1 , wherein L 1 and L 3 are each a direct bond and L 2 is fluoroalkylene, wherein the polymer has the following structure (Ib): wherein: R 1 , R 2 and R 3 are, at each occurrence, independently H or alkyl; Rf 2 is, at each occurrence, independently fluoroalkylene; Z 1 is, at each occurrence, independently F or fluoroalkyl; Q is, at each occurrence, independently an alkyl group, a cycloalkyl group, a hydroxyalkyl group, an alkoxy group, an alkoxyalkyl group, an adamantyl group, a cedryl group, a norbornyl group, or a tricyclodecanyl group; X 1 and X 2 are, at each occurrence, independently hydroxyl, epoxy, melamine, alkene, or alkyne; and a 1 is, at each occurrence, an integer from 0 to 4; and 0<x/(x+y+z)<1, 0<y/(x+y+z)<1 and 0<z/(x+y+z)<1.
  15. 15 . The method of claim 1 , wherein y is 0, L 1 is fluoroalkylene and L 3 is a direct bond, wherein the polymer has the following structure (Ic): wherein: R 1 and R 3 are, at each occurrence, independently H or alkyl; Rf 1 is, at each occurrence, independently fluoroalkylene; Z 1 is, at each occurrence, independently F or fluoroalkyl; Q is, at each occurrence, independently an alkyl group, a cycloalkyl group, a hydroxyalkyl group, an alkoxy group, an alkoxyalkyl group, an adamantyl group, a cedryl group, a norbornyl group, or a tricyclodecanyl group; X 1 is, at each occurrence, independently hydroxyl, epoxy, melamine, alkene, or alkyne; a 1 is, at each occurrence, an integer from 0 to 4, and 0<x/(x+y+z)<1 and 0<z/(x+y+z)<1.
  16. 16 . A method of forming a semiconductor device, comprising: depositing a photoresist layer over a material layer on a substrate, wherein the photoresist layer comprises a polymer, a crosslinker and a photoacid generator; exposing the photoresist layer to radiation, thereby forming a crosslinked polymer in portions of the photoresist layer exposed to the radiation; developing the photoresist layer to form a patterned photoresist layer; and etching the material layer using the patterned photoresist layer as an etch mask, wherein the polymer has the following structure (I): wherein: L 1 and L 2 are, at each occurrence, independently a direct bond or a carbonyloxy or halogenated alkylene linker, provided that at least one of L 1 and L 2 is a halogenated alkylene linker; L 3 is, at each occurrence, a direct bond; Ar 1 is, at each occurrence, independently halogenated or non-halogenated arylene or halogenated or non-halogenated heteroarylene; Q is, at occurrence, independently an acid labile group; X 1 and X 2 are, at each occurrence, independently a reactive group, or protected form thereof, capable of forming a covalent bond with the crosslinker; R 1 , R 2 and R 3 are, at each occurrence, independently H, alkyl or alkoxy; and 0<x/(x+y+z)<1, 0<y/(x+y+z)<1 and 0<z/(x+y+z)<1.
  17. 17 . The method of claim 16 , wherein: L 1 and L 2 each independently have one of the following structures: Ar 1 has one of the following structures: Q has one of the following structures: X 1 and X 2 are, at each occurrence, independently hydroxyl, alkoxy, amine, thiol, ester, melamine, alkene, alkyne, epoxy, aziridine, oxetane, aldehyde, ketone or a carboxylic acid; and R 1 , R 2 and R 3 are each independently H or methyl.
  18. 18 . The method of claim 16 , wherein the polymer has one of the following structures:
  19. 19 . A method of forming a semiconductor device, comprising: depositing a material layer over a substrate; applying a photoresist composition comprising a polymer, a crosslinker and a photoacid generator over the material layer to form a photoresist layer; exposing the photoresist layer to an extreme ultraviolet (EUV) radiation to generate a photoacid, which catalyzes the reaction between the polymer and the crosslinker to form a crosslinked polymer in exposed regions of the photoresist layer; baking the photoresist layer; removing exposed or unexposed regions of the photoresist layer to form a patterned photoresist layer; and etching the material layer using the patterned photoresist layer as an etch mask, wherein the polymer has the following structure (Ia): wherein: R 1 , R 2 and R 3 are, at each occurrence, independently H or alkyl; Rf 1 and Rf 2 are, at each occurrence, independently fluoroalkylene; Z 1 is, at each occurrence, independently F or fluoroalkyl; Q is, at each occurrence, independently an alkyl group, a cycloalkyl group, a hydroxyalkyl group, an alkoxy group, an alkoxyalkyl group, an adamantyl group, a cedryl group, a norbornyl group, or a tricyclodecanyl group; X 1 and X 2 are, at each occurrence, independently hydroxyl, epoxy, melamine, alkene, or alkyne; a 1 is, at each occurrence, an integer from 0 to 4; and 0<x/(x+y+z)<1, 0≤y/(x+y+z)<1 and 0<z/(x+y+z)<1.
  20. 20 . The method of claim 19 , further comprising baking the photoresist layer prior to exposing the photoresist layer to the EUV radiation.

Description

BACKGROUND The semiconductor integrated circuit (IC) industry has experienced exponential growth. Technological advances in IC materials and design have produced generations of ICs where each generation has smaller and more complex circuits than the previous generation. In the course of IC evolution, functional density (i.e., the number of interconnected devices per chip area) has generally increased while geometry size (i.e., the smallest component (or line) that can be created using a fabrication process) has decreased. This scaling down process generally provides benefits by increasing production efficiency and lowering associated costs. Such scaling down has also increased the complexity of processing and manufacturing ICs. BRIEF DESCRIPTION OF THE DRAWINGS Aspects of the present disclosure are best understood from the following detailed description when read with the accompanying figures. It is noted that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion. FIG. 1 is a flow chart of a method for fabricating a semiconductor device, in accordance with some embodiments of the present disclosure. FIGS. 2A-2G are cross-sectional views of a semiconductor device fabricated using the method of FIG. 1, in accordance with some embodiments of the present disclosure. FIG. 3 illustrates examples of crosslinkers having epoxy groups according to some embodiments of the present disclosure. FIG. 4 illustrates examples of crosslinkers having hydroxyl groups according to some embodiments of the present disclosure. FIG. 5 illustrates examples of crosslinkers having melamine groups according to some embodiments of the present disclosure. FIG. 6 illustrates examples of crosslinkers having alkene groups according to some embodiments of the present disclosure. DETAILED DESCRIPTION The following disclosure provides many different embodiments, or examples, for implementing different features of the provided subject matter. Specific examples of components, values, operations, materials, arrangements, or the like, are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. Other components, values, operations, materials, arrangements, or the like, are contemplated. For example, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed between the first and second features, such that the first and second features may not be in direct contact. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. Further, spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. The spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. System may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may likewise be interpreted accordingly. “Alkyl” by itself or as part of another substituent, refers to a straight or branched hydrocarbon chain group consisting solely of carbon and hydrogen atoms, containing no unsaturation, having from one to twelve carbon atoms (C1-C12 alkyl), one to eight carbon atoms (C1-C8 alkyl) or one to six carbon atoms (C1-C6 alkyl), and which is attached to the rest of the molecule by a single bond, e.g., methyl, ethyl, n-propyl, 1-methylethyl (iso-propyl), n-butyl, n-pentyl, 1,1-dimethylethyl (t-butyl), 3-methylhexyl, 2-methylhexyl, and the like. Unless stated otherwise specifically in the specification, an alkyl group is optionally substituted. “Alkylene” as used herein refers to a straight or branched divalent hydrocarbon chain linking the rest of the molecule to a radical group, consisting solely of carbon and hydrogen, containing no unsaturation, and having from one to twelve carbon atoms, e.g., methylene, ethylene, propylene, n-butylene, ethenylene, propenylene, n-butenylene, propynylene, n-butynylene, and the like. The alkylene chain is attached to the rest of the molecule through a single bond and to the radical group through a single bond. The points of attachment of the alkylene chain to the rest of the molecule and to the radical group can be through one carbon or any two carbons within the chain. Unle