Chemically Amplified Resist Pattern Formation Process
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current patterning technologies face challenges in forming fine rectangular space patterns with narrow slits, particularly in the double patterning process, where the use of positive resist materials leads to deformation and scum formation, while negative tone development results in elliptic shapes, and existing methods require multiple etching steps and hard masks.
Innovation Solution
A pattern forming process involving a chemically amplified positive resist composition that undergoes partial crosslinking to become insoluble in organic solvents, allowing for the simultaneous formation of a positive and negative pattern using a single hard mask and a single dry etching step, with the second resist material developed in organic solvent to prevent scum formation and achieve high contrast.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If positive resist material is used for double patterning, then the first pattern can be formed, but the pattern deforms and scum forms during subsequent processing
Solution Approach 1:
The patent changes the chemical parameters of the first resist material by using a chemically amplified positive resist that becomes insoluble in organic solvents after exposure and development. This chemical transformation allows the first pattern to maintain its shape during subsequent organic solvent development of the second resist, preventing scum formation while preserving pattern accuracy
Solution Approach 2:
Instead of using conventional positive resist that remains soluble throughout the process, the patent inverts the solubility behavior by selecting a resist that transforms from soluble to insoluble in organic solvents after exposure. This inversion allows the first pattern to serve as a stable mask during the second exposure and organic solvent development step
2Manufacturing precision
If negative tone development is used, then high contrast can be achieved, but the pattern becomes elliptic instead of rectangular
Solution Approach 1:
The patent segments the patterning process into two distinct parts: first exposure forming a positive pattern with a chemically amplified resist, and second exposure forming a negative pattern with conventional resist. This segmentation allows each step to optimize for its specific function - the first step creates precise rectangular features that serve as masks, while the second step fills the spaces, avoiding the elliptic distortion problem of conventional negative tone development
3Manufacturing precision
If conventional double patterning is used, then fine patterns can be formed, but multiple etching steps and hard masks are required
Solution Approach 1:
The patent makes the first resist pattern serve multiple functions: it acts as both the pattern definition layer from the first exposure and as a protective mask during the organic solvent development of the second resist. This multi-functionality eliminates the need for separate hard mask layers and multiple etching steps, reducing process complexity while maintaining fine pattern resolution
Solution Approach 2:
The patent merges the first resist pattern with the mask function by selecting a chemically amplified positive resist that becomes insoluble in organic solvents. This merging combines the pattern formation function with the mask protection function into a single layer, eliminating the need for separate hard mask layers and reducing the total number of process steps
Data Source
AI summary
A pattern is formed by coating a first chemically amplified positive resist composition comprising a resin comprising recurring units having an acid labile group so that it may turn soluble in alkaline developer upon elimination of the acid labile group, a photoacid generator, and a first organic solvent, onto a processable substrate, prebaking, exposing, PEB, and developing in an alkaline developer to form a positive pattern; heating the positive pattern to render it resistant to a second organic solvent used in a second resist composition; coating the second resist composition, prebaking, exposing, PEB, and developing in a third organic solvent to form a negative pattern. The positive pattern and the negative pattern are simultaneously formed.