Semiconductor Patterning with Trimmed Spacer Etch Masks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for forming patterns in semiconductor devices, such as FinFETs, face challenges in achieving varying line widths due to the limitations of double-patterning technologies using spacers, which typically result in patterns with the same line width.
Innovation Solution
The method involves forming sacrificial film patterns and spacers on a semiconductor substrate, removing the sacrificial films, trimming the spacers to achieve different line widths, and using the trimmed spacers as etch masks to form hard mask film patterns, allowing for the creation of semiconductor patterns with varying line widths while maintaining equal pitches between neighboring portions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If spacer-based double-patterning technology is used to form patterns, then pattern formation is achieved, but all patterns have the same line width which limits design flexibility
Solution Approach 1:
The patent applies local quality by introducing a trimming process that selectively modifies the line width of spacers in specific regions. The trimming step removes material from spacer sidewalls to create different line widths (first line width for first spacers, second line width for second spacers) while maintaining the same pitch, enabling local variation in pattern dimensions without changing the overall patterning process
Solution Approach 2:
The patent segments the patterning process into distinct stages: forming sacrificial patterns, depositing spacers, removing sacrificial patterns, and selectively trimming spacers. This segmentation allows independent control of spacer dimensions at different locations, enabling the formation of semiconductor patterns with varying line widths from a unified process flow
2Adaptability or versatility
If traditional spacer-based double-patterning is used, then manufacturing simplicity is maintained, but design freedom for varying line widths is lost
Solution Approach 1:
The patent applies preliminary action by forming all spacers with a uniform initial line width before the trimming step. This preliminary uniform formation ensures precise control and consistency, while the subsequent selective trimming introduces the desired variation. The preliminary uniform spacer formation serves as a controlled baseline from which precise line width variations are intentionally created
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 approach enables the formation of semiconductor patterns with different line widths, enhancing design freedom and allowing for the fabrication of FinFETs with varying threshold voltages, thereby overcoming the limitations of traditional spacer-based double-patterning technologies.
Implementation Method 1
forming first and second hard mask film patterns by etching the hard mask film using the first spacer and the trimmed second spacer as an etch mask
Implementation Method 2
forming first and second semiconductor patterns having different line widths by etching the semiconductor substrate using the first and second hard mask film patterns as an etch mask
Data Source
AI summary
Methods of forming patterns of a semiconductor device are provided. The methods may include forming a hard mask film on a semiconductor substrate. The methods may include forming first and second sacrificial film patterns that are spaced apart from each other on the hard mask film. The methods may include forming a first spacer on opposing sidewalls of the first sacrificial film pattern and a second spacer on opposing sidewalls of the second sacrificial film pattern. The methods may include removing the first and second sacrificial film patterns. The methods may include trimming the second spacer such that a line width of the second spacer becomes smaller than a line width of the first spacer. The methods may include forming first and second hard mask film patterns by etching the hard mask film using the first spacer and the trimmed second spacer as an etch mask.