Positive Resist Composition for Thermal Flow Pattern Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional ArF excimer laser lithography resist compositions face challenges in thermal flow processes due to high glass transition temperatures of base resins, making it difficult to form resist patterns with precise control over pattern size.
Innovation Solution
A positive resist composition incorporating a polymer compound with structural units that decrease glass transition temperature, such as those represented by general formulas (a0) and (a0)′, which exhibit increased alkali solubility under acid action and contain acid-dissociable dissolution inhibiting groups, allowing for controlled thermal flow and pattern formation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a conventional base resin (PHS-based resin) is used in ArF excimer laser lithography, then transparency to KrF excimer laser (248 nm) is improved, but transparency to light having wavelength of 193 nm deteriorates, resulting in low resolution
Solution Approach 1:
The patent changes the chemical composition parameters of the base resin by incorporating specific structural units (formula a0 with aliphatic cyclic groups and formula a2 with lactone-containing cyclic groups) that modify the resin's optical properties, enabling high transparency at 193 nm wavelength while maintaining necessary functional characteristics
Solution Approach 2:
The patent creates a composite resin system by combining multiple structural units (a0, a1, a2) with specific functional properties within a single polymer chain, achieving a balance between optical transparency, thermal properties, and lithographic performance that cannot be obtained with conventional homogeneous resins
2Stability of the object's composition
If a base resin with high glass transition temperature is used in thermal flow process, then pattern formation stability is improved, but controllability of resist pattern size deteriorates
Solution Approach 1:
The patent modifies the glass transition temperature parameter of the base resin by incorporating structural units with specific thermal properties (aliphatic cyclic groups and lactone-containing cyclic groups), lowering the Tg to an optimal range that enables both adequate pattern formation stability and precise size control during thermal flow processing
Solution Approach 2:
The patent creates a resin system with dynamic thermal properties that allow the material to transition between different states (glassy and rubbery phases) at processing temperatures, enabling controlled flow behavior that balances stability and controllability during the thermal flow process
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 resist composition enables excellent controllability of resist pattern size in thermal flow processes, allowing for the formation of finer patterns with improved lithography characteristics and reduced glass transition temperature, facilitating easier pattern formation and processing.
Implementation Method 1
an acid generator component (B) which generates an acid upon exposure
Implementation Method 2
the resist pattern is softened and allowed to flow in the space direction of the pattern by heating
Implementation Method 3
a thermal flow process in which a resist pattern is formed by a conventional lithography technique and the resist pattern is subjected to a heat treatment thereby conducting miniaturization of the pattern size
Data Source
AI summary
Disclosed is a positive resist composition comprising a resin component (A) and an acid generator component (B), wherein the component (A) contains a polymer compound (A1) containing a structural unit (a0) represented by formula (a0) shown below and a structural unit (a2) derived from an acrylate ester containing a lactone-containing cyclic group:(wherein R represents a hydrogen atom, a halogen atom, a lower alkyl group, or a halogenated lower alkyl group; Y1 represents an aliphatic cyclic group; Z represents an acid dissociable, dissolution inhibiting group containing a tertiary alkyl group; a represents an integer from 1 to 3, b represents an integer from 0 to 2, and a+b=1 to 3; and c, d and e each represents, independently, an integer from 0 to 3).