Semiconductor Mask Layout for OPC at Step Corners
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In semiconductor manufacturing, the optical proximity effect and loading effect during photolithography and etch processes lead to inaccuracies in transferring circuit patterns from masks to wafers, necessitating effective correction techniques to ensure precise pattern transfer.
Innovation Solution
A method for fabricating masks using optical proximity correction (OPC) involves generating a first target pattern with specific edge configurations, modifying it to create a second target pattern with recesses and protrusions, and iteratively applying OPC to achieve a final pattern that accurately represents the design, thereby improving the mask's edge accuracy and reducing manufacturing time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If optical proximity correction is applied to correct pattern deformation, then manufacturing precision is improved, but device complexity increases due to additional processing steps
Solution Approach 1:
The patent applies optical proximity correction in advance during mask fabrication by generating a corrected pattern that pre-compensates for anticipated deformation. The correction algorithm predicts optical proximity effects and loading effects before photolithography, and modifies the mask pattern accordingly, so that the final transferred pattern matches the design pattern without requiring additional correction steps during manufacturing.
2Manufacturing precision
If mask pattern is modified with recesses and protrusions for correction, then pattern transfer accuracy is improved, but mask data complexity increases
Solution Approach 1:
The patent applies local quality by modifying only specific critical regions of the mask pattern where optical proximity effects cause deformation. Instead of uniformly complicating the entire mask, the correction algorithm identifies areas requiring adjustment (such as regions with inner corners and outer corners of step portions) and applies localized modifications like recesses and protrusions only where needed, maintaining simplicity in non-critical areas.
3Manufacturing precision
If iterative optical proximity correction is performed, then manufacturing precision is improved, but productivity decreases due to extended processing time
Solution Approach 1:
The patent performs optical proximity correction as a preliminary computational step during mask data preparation, using algorithms that predict and compensate for deformation before physical mask fabrication begins. This pre-computation approach consolidates correction iterations in the design phase rather than requiring repeated physical mask adjustments, thereby improving precision without significantly impacting production throughput.
Data Source
AI summary
A method for fabricating a mask for manufacturing a semiconductor device is provided. The method includes generating a first target pattern including a step portion having an inner corner and an outer corner that are spaced apart in a vertical direction; generating a second target pattern from the first target pattern; performing optical proximity correction on the second target pattern to generate a final pattern; and fabricating the mask using the final pattern. Generating the second target pattern includes forming a recess extending inwardly and in a diagonal direction relative to the inner corner of the step portion; and forming a protrusion protruding outwardly and in the diagonal direction relative to the outer corner of the step portion.