Mask Pattern Generation Using Lower Layer Data

Solution Overview

Problem

Existing methods for generating mask patterns do not effectively consider the relationship between the position of the lower layer pattern and the auxiliary pattern during transfer, leading to potential defects and limited improvement in resolving properties of the main pattern.

Innovation Solution

A method that uses computer-generated data for both the main and auxiliary patterns, where the auxiliary pattern's generation condition is set based on the lower layer's pattern data to ensure it is transferred only on specific positions, improving the resolving properties of the main pattern without affecting the lower layer's structure.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If the size of the auxiliary pattern is increased to improve the resolving property of the main pattern, then the resolving property is improved, but the auxiliary pattern itself is transferred to the wafer causing defects

Engineering Contradiction:

Improveresolving property of main patternVSAvoiddefect rate of lower layer

Core Design Contradiction:

Manufacturing precisionVSReliability

Solution Approach 1:

The patent applies local quality by differentiating the treatment of different spatial regions. The auxiliary pattern is designed with locally varying characteristics: in regions where the lower layer has patterns, the auxiliary pattern size is controlled to prevent transfer; in regions where the lower layer has spaces, the auxiliary pattern can be larger to improve main pattern resolution. This spatially differentiated approach allows the same auxiliary pattern structure to serve different functions in different locations.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent implements preliminary action by performing OPC processing on the auxiliary pattern before determining its final configuration. The system calculates the aerial image of the auxiliary pattern in advance, uses this information to determine appropriate auxiliary pattern sizes, and then applies these predetermined sizes to prevent unwanted transfer. This pre-calculation and pre-determination approach allows the system to proactively prevent defects before they occur during actual manufacturing.

Inventive Principle:

Principle #10Preliminary action

2Manufacturing precision

If the auxiliary pattern is completely transferred to the wafer, then the resolving property improvement is maximized, but the lower layer structure is adversely affected

Engineering Contradiction:

Improveresolving property of main patternVSAvoidprocessing of lower layer by auxiliary pattern

Core Design Contradiction:

Manufacturing precisionVSObject-affected harmful factors

Solution Approach 1:

The patent applies local quality by differentiating the treatment of different spatial regions. The auxiliary pattern is designed with locally varying characteristics: in regions where the lower layer has patterns, the auxiliary pattern size is controlled to prevent transfer; in regions where the lower layer has spaces, the auxiliary pattern can be larger to improve main pattern resolution. This spatially differentiated approach allows the same auxiliary pattern structure to serve different functions in different locations.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent implements preliminary action by performing OPC processing on the auxiliary pattern before determining its final configuration. The system calculates the aerial image of the auxiliary pattern in advance, uses this information to determine appropriate auxiliary pattern sizes, and then applies these predetermined sizes to prevent unwanted transfer. This pre-calculation and pre-determination approach allows the system to proactively prevent defects before they occur during actual manufacturing.

Inventive Principle:

Principle #10Preliminary action

3Reliability

If the auxiliary pattern size is limited to prevent transfer, then the lower layer is protected, but the resolving property improvement is limited

Engineering Contradiction:

Improveintegrity of lower layerVSAvoidresolving property of main pattern

Core Design Contradiction:

ReliabilityVSManufacturing precision

Solution Approach 1:

The patent applies local quality by differentiating the treatment of different spatial regions. The auxiliary pattern is designed with locally varying characteristics: in regions where the lower layer has patterns, the auxiliary pattern size is controlled to prevent transfer; in regions where the lower layer has spaces, the auxiliary pattern can be larger to improve main pattern resolution. This spatially differentiated approach allows the same auxiliary pattern structure to serve different functions in different locations.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent applies dimensionality change by adding a spatial dimension to the auxiliary pattern size determination. Instead of using a uniform size constraint, the system varies the auxiliary pattern size based on the two-dimensional layout of the lower layer pattern. This creates a three-dimensional solution space (x, y, size) that optimizes both protection and resolution improvement simultaneously.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Data Source

PatentUS8986912B2Method for generating mask pattern

Publication Date: 2015.03.24 CANON KK

AI summary

A method for generating, via a computer, a mask pattern to be used for an exposure apparatus that exposes an image of the mask pattern on a substrate by irradiating a mask includes obtaining data of a main pattern to be formed on the substrate, and data of a pattern of a lower layer of a layer to which the main pattern is transferred, setting a generation condition for an auxiliary pattern with respect to the main pattern using data of the pattern of the lower layer, determining the auxiliary pattern using the generation condition, and generating data of the mask pattern including the main pattern and the determined auxiliary pattern.