Polymerizable Photoacid Generators for EUV Lithography
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current photoresist technologies face challenges in controlling outgassing and linewidth roughness, especially in advanced lithographies using extreme ultraviolet (EUV) radiation, where conventional photoacid generators compromise either outgassing or linewidth quality.
Innovation Solution
Development of novel polymerizable photoacid generators with a specific cation-anion structure, including a fluorinated sulfonic acid, sulfonamide, or sulfonimide anion and an aryl-substituted onium cation, attached to an olefinic ester polymerizable group, which reduces decomposition products and maintains sensitivity to EUV radiation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If conventional photoacid generators (e.g., triphenylsulfonium cation-based) are used, then outgassing control is improved, but linewidth roughness deteriorates
Solution Approach 1:
The patent modifies the chemical structure of the photoacid generator by changing the cation from conventional triphenylsulfonium to a novel structure with formula (II) where X is S or I, each R0 is independently a C1-30 alkyl, cycloalkyl, or aryl group, and a is 2 or 3. This structural parameter change simultaneously improves outgassing control and reduces linewidth roughness, resolving the technical contradiction between these two parameters.
Solution Approach 2:
The invention creates a composite photoacid generator structure combining a specific cation (formula II) with a fluorinated sulfonic acid, sulfonamide, or sulfonimide anion (formula I). This composite structure achieves synergistic effects where the cation provides low outgassing and the fluorinated anion provides both low outgassing and improved linewidth control, resolving the contradiction between outgassing and linewidth roughness.
2Object-generated harmful factors
If photoacid generators with improved outgassing are used, then outgassing control is improved, but sensitivity to EUV radiation deteriorates
Solution Approach 1:
The patent introduces fluorinated groups in the anion structure (formula I where A is a fluorine-substituted C1-30 alkylene, cycloalkylene, arylene, or alkylene-arylene group) to enhance EUV radiation sensitivity. This parameter change in the chemical structure allows the photoacid generator to maintain high sensitivity to EUV radiation while simultaneously achieving improved outgassing control, resolving the technical contradiction between these two parameters.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The new photoacid generators exhibit low outgassing and improved linewidth roughness, providing enhanced performance in EUV lithography with reduced volatile degradation products and improved sensitivity compared to conventional PAGs.
Implementation Method 1
Chemical compounds which decompose to generate acids when exposed to radiation in the ultraviolet region of the spectrum
Implementation Method 2
Q is a halogenated or non-halogenated, C2-30 olefin-containing group
Data Source
AI summary
A compound has formula (I):Q-O-(A)-Z−G+ (I)wherein Q is a halogenated or non-halogenated, C2-30 olefin-containing group, A is a fluorine-substituted C1-30 alkylene group, a fluorine-substituted C3-30 cycloalkylene group, a fluorine-substituted C6-30 arylene group, or a fluorine-substituted C7-30 alkylene-arylene group, Z is an anionic group comprising sulfonate, sulfonamide, or sulfonimide, and G+ has formula (II):wherein X is S or I, each R0 is halogenated or non-halogenated and is independently C1-30 alkyl group; a polycyclic or monocyclic C3-30 cycloalkyl group; a polycyclic or monocyclic C4-30 aryl group; or a combination of these, wherein when X is S, one of the R0 groups is optionally attached to one adjacent R0 group by a single bond, and a is 2 or 3, wherein when X is I, a is 2, or when X is S, a is 3. A copolymer, a photoresist, a coated substrate and method of patterning are disclosed.