Resist Patterning via Positive-Negative Reversal for Fine Patterns
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current resist patterning technologies face challenges in forming fine patterns due to low resolution and dimensional variations in thermal shrinkage methods, and the use of negative resists results in low overlay accuracy and increased complexity in the double patterning process.
Innovation Solution
A resist patterning process involving a positive-negative reversal using a chemically-amplified positive resist film with acid-labile groups, where the resist is partially crosslinked to maintain solubility in alkaline wet-etching, allowing for the use of organic silicon compounds and high-polar solvents, enabling precise formation of fine patterns with high optical contrast.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a negative resist is used for fine pattern formation, then the pattern can be formed, but the overlay accuracy deteriorates and the process complexity increases
Solution Approach 1:
The invention uses a positive resist to form a positive pattern, then performs a positive-negative reversal to obtain the final negative pattern. This inverts the conventional approach of directly using negative resist, thereby achieving fine pattern formation with high overlay accuracy while simplifying the double patterning process
Solution Approach 2:
The invention performs preliminary crosslinking of the positive resist pattern before the reversal step. This preliminary action stabilizes the pattern structure and prevents dimensional variations during subsequent processing, ensuring high precision in the final fine pattern while maintaining process simplicity
2Manufacturing precision
If a positive pattern is reversed to negative pattern by alkaline etching, then the negative pattern is formed, but the positive pattern solubility in alkaline liquid must be maintained which conflicts with crosslinking
Solution Approach 1:
The invention applies local quality by performing partial crosslinking only in specific regions of the positive resist pattern. The crosslinking density is controlled to maintain alkaline solubility where needed for reversal, while providing sufficient structural stability in other regions. This localized differentiation resolves the conflict between solubility requirements and crosslinking stability
Solution Approach 2:
The invention changes the chemical parameters of the resist by introducing acid-labile groups that can be selectively removed. By controlling the degree of crosslinking and the presence of acid-labile groups, the resist maintains appropriate solubility in alkaline liquids for pattern reversal while achieving the necessary structural stability, thereby enabling precise negative pattern formation
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
This method allows for the formation of precise, high-resolution patterns with improved overlay accuracy and reduced complexity, enabling the creation of fine space and hole patterns with enhanced precision and cost-effectiveness.
Implementation Method 1
a chemically-amplified positive resist film containing a resin having acid-labile groups dissociable by an acid generated during exposure
Implementation Method 2
the acid-labile groups are dissociated by the acid generated during exposure
Implementation Method 3
the resist is partially crosslinked to maintain solubility in alkaline wet-etching
Data Source
AI summary
The present invention provides a patterning process, in which a resistance with regard to an organic solvent used for a composition for formation of a reverse film is rendered to a positive pattern to the degree of necessity and yet solubility into an alkaline etching liquid is secured, thereby enabling to finally obtain a negative image by a positive-negative reversal by performing a wet etching using an alkaline etching liquid.A resist patterning process of the present invention using a positive-negative reversal comprises at least a step of forming a resist film by applying a positive resist composition; a step of obtaining a positive pattern by exposing and developing the resist film; a step of crosslinking the positive resist pattern thus obtained; a step of forming a reverse film; and a step of reversing the positive pattern to a negative pattern by dissolving into an alkaline wet-etching liquid for removal.