EUV Mask Layout Correction for Photolithography Precision
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In advanced photolithography processes using extreme ultraviolet (EUV) light, the precision of the photolithography pattern transferred to a silicon wafer is compromised due to deviations caused by varying azimuth angles and polarization angles of incident rays, leading to reduced accuracy and process window size in the photolithography pattern formation.
Innovation Solution
A correction method for mask layout is introduced, where position information of main patterns and auxiliary patterns is obtained and arranged to optimize spacings between them, accommodating different azimuth angles and polarization angles, thereby enhancing the process window and accuracy of the photolithography pattern. This involves determining specific spacings and arrangements of auxiliary patterns relative to main patterns based on their positions and orientations to minimize deviations and optimize the exposure process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If extreme ultraviolet light is used as a light source in photolithography, then a phot lithographic pattern with a small critical dimension may be formed, but precision of the photolithography pattern formed may be reduced due to deviations caused by varying azimuth angles and polarization angles of incident rays
Solution Approach 1:
The patent applies preliminary action by pre-calculating and pre-positioning auxiliary patterns around main patterns in the mask layout before photolithography. The auxiliary patterns are strategically placed to compensate for anticipated deviations caused by varying azimuth angles and polarization angles of incident EUV rays, thereby correcting precision errors before the actual patterning process occurs
Solution Approach 2:
The patent implements local quality by creating non-uniform spacing between auxiliary patterns and main patterns. The spacing is locally adjusted based on the position of each main pattern in the target layout, with different spacing values applied in different regions to account for position-dependent deviations caused by the arc-shaped slit geometry and varying incident ray angles
2Manufacturing precision
If auxiliary patterns are added to correct precision deviations, then manufacturing precision is improved, but device complexity increases due to additional patterns in the mask layout
Solution Approach 1:
The patent applies segmentation by dividing the correction function into multiple auxiliary patterns distributed around each main pattern. Instead of using a single complex correction structure, the correction is segmented into multiple simpler auxiliary patterns with different spacings, making the overall system more manageable and easier to fabricate despite the increased number of elements
3Manufacturing precision
If non-uniform spacing of auxiliary patterns is used to compensate for position-dependent deviations, then manufacturing precision is improved, but ease of manufacture decreases due to complex spacing calculations and arrangements
Solution Approach 1:
The patent applies parameter changes by systematically varying the spacing parameter between auxiliary patterns and main patterns based on their relative positions. The spacing is changed as a function of position in the target layout, allowing the mask to compensate for position-dependent deviations while maintaining a regular, predictable pattern structure that simplifies fabrication
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 method improves the accuracy and size of the process window in photolithography pattern formation by maintaining suitable spacings between auxiliary and main patterns, even under varying azimuth and polarization angles, simplifying mask fabrication and reducing fabrication time while enhancing the precision of the photolithography process.
Implementation Method 1
light irradiates a silicon wafer coated with a photoresist layer through a mask with light-transmitting areas and reflective areas, and photochemically reacts with a photoresist of the photoresist layer
Data Source
AI summary
Correction method of mask layout and mask containing corrected layout are provided. The method includes providing a target layout including a plurality of main patterns. Each main pattern includes a first side and an opposite second side. Extending directions of the first side and the second side are perpendicular to a first direction. Each main pattern also includes a third side and an opposite fourth side. Extension directions of the third side and the fourth side are perpendicular to a second direction. The second direction and the first direction are perpendicular to each other. The method also includes acquiring position information of each main pattern, and obtaining position information of auxiliary patterns adjacent to each main pattern. The method also includes, according to the position information of the auxiliary patterns adjacent to each main pattern, arranging the auxiliary patterns adjacent to each main pattern around each main pattern.