EUV Mask Border Magnetic Layer for Particle Deflection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In the semiconductor industry, extreme ultraviolet (EUV) lithography faces challenges due to phase defects caused by magnetic particles like iron and nickel, which contaminate EUV masks and lead to critical dimension errors during wafer exposure, as these particles can attach to the pattern region of the EUV mask and affect the fidelity of the lithographically transferred pattern.

Innovation Solution

The introduction of a patterned absorber layer made of non-magnetic material in the pattern region and a magnetic layer in the border region of the EUV mask, where the magnetic field attracts and deflects magnetic particles away from the pattern region, preventing contamination and improving pattern fidelity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a conventional EUV mask without magnetic layer is used, then the mask structure is simpler and easier to manufacture, but magnetic particles attach to the pattern region causing phase defects and critical dimension errors

Engineering Contradiction:

Improvepattern fidelityVSAvoidmask structure

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The mask is segmented into distinct functional regions: a pattern region containing the circuit pattern and a border region containing a magnetic layer. This segmentation allows the magnetic layer to be positioned specifically in the border region where it can attract magnetic particles away from the pattern region, thereby improving pattern fidelity without requiring magnetic material throughout the entire mask structure.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The magnetic layer acts as an intermediary element that intercepts magnetic particles (iron, nickel) in the border region before they can reach and contaminate the pattern region. This intermediary magnetic layer deflects magnetic particles away from the critical pattern area, preventing phase defects and critical dimension errors while maintaining optical performance.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If the magnetic layer is positioned in the pattern region, then magnetic particles are attracted and prevented from attaching, but the magnetic material interferes with the lithographic pattern transfer

Engineering Contradiction:

Improvecontamination preventionVSAvoidpattern accuracy

Core Design Contradiction:

ReliabilityVSManufacturing precision

Solution Approach 1:

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The magnetic layer is applied locally only in the border region of the mask, not uniformly across the entire mask surface. This local application ensures that magnetic particles are attracted and prevented from reaching the pattern region, while the pattern region itself remains free of magnetic material that would interfere with lithographic pattern transfer, thus maintaining both contamination prevention and pattern accuracy.

Inventive Principle:

Principle #3Local quality

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 solution effectively reduces patterning errors by preventing magnetic particles from attaching to the pattern region of the EUV mask, thereby enhancing the accuracy and fidelity of the lithographically transferred patterns on semiconductor wafers.

Implementation Method 1

a magnetic layer in the border region, where the magnetic field attracts and deflects magnetic particles away from the pattern region

Methodology Applied

Scientific EffectMagnetic field: Magnetic Field

Data Source

PatentUS20240393674A1Methods for forming extreme ultraviolet mask comprising magnetic material

Publication Date: 2024.11.28 TAIWAN SEMICONDUCTOR MANUFACTURING CO LTD

AI summary

An extreme ultraviolet mask includes a substrate, a reflective multilayer stack over the substrate, a capping layer over the reflective multilayer stack, a patterned absorber layer over a first portion of the capping layer, and a magnetic layer over a second portion of the capping layer around the first portion.