Lithography Component Electret Clamping for Low-Pressure Handling

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Lithographic apparatuses operating at low pressures face challenges in securely clamping components like reticles and protective plates without applying unsafe high voltages, and existing solutions like vacuum clamping and mechanical feet lead to contamination and wear.

Innovation Solution

Employ thin-film electret coatings on components to achieve electrostatic adhesion without external forces, utilizing contact electrification or inter-metallic bonding for secure clamping in low-pressure environments.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If vacuum clamping is used to hold components in place, then component positioning is secure, but contamination occurs during cleaning and venting operations

Engineering Contradiction:

Improvecomponent positioningVSAvoidcontamination

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent extracts the harmful vacuum environment from the clamping mechanism by introducing gas pressure to the rear surface of the component. This allows the component to be held securely during normal operation while enabling safe exposure during cleaning and venting operations, as the component is no longer dependent on vacuum for positioning.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent changes the pressure parameter from negative (vacuum) to positive (gas pressure) on the rear surface of the component. This parameter change allows the component to be securely held during imaging operations while enabling safe exposure during maintenance operations, resolving the contradiction between secure positioning and contamination risk.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If electrostatic clamping with high voltages is used to hold components, then component positioning is secure in low pressure, but safety hazards arise during flushing and venting

Engineering Contradiction:

Improvecomponent positioningVSAvoidsafety hazards

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent replaces the electrostatic field-based clamping system with a gas pressure-based mechanical system. By introducing gas pressure to the rear surface, the component is held securely through mechanical pressure rather than high voltage electrostatic fields, eliminating safety hazards during flushing and venting operations while maintaining secure positioning.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Object-affected harmful factors

If protective plates are used instead of reticles, then contamination of the support structure is reduced, but component wear increases due to mechanical contact

Engineering Contradiction:

ImprovecontaminationVSAvoidwear

Core Design Contradiction:

Object-affected harmful factorsVSObject-generated harmful factors

Solution Approach 1:

The patent replaces mechanical contact-based protective plates with a gas pressure-based holding system. Components are held securely through gas pressure applied to the rear surface without mechanical contact, eliminating wear while maintaining protection during cleaning and venting operations.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

4Object-affected harmful factors

If reticles are removed from the support structure during transport, then damage and contamination are prevented, but component positioning accuracy is lost

Engineering Contradiction:

Improvedamage and contaminationVSAvoidpositioning accuracy

Core Design Contradiction:

Object-affected harmful factorsVSMeasurement precision

Solution Approach 1:

The patent extracts the harmful vacuum dependency from the clamping system, allowing components to be securely held during transport through gas pressure rather than vacuum. This enables components to remain installed on the support structure during transport without risk of damage or contamination, while maintaining positioning accuracy through the gas pressure holding mechanism.

Inventive Principle:

Principle #2Taking out (Extraction)

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

Provides safe and reliable clamping of components during operations like flushing, venting, and transport, minimizing contamination and wear, while maintaining component positioning accuracy.

Implementation Method 1

Employ thin-film electret coatings on components to achieve electrostatic adhesion without external forces

Methodology Applied

Scientific EffectElectrostatic adhesion: Electrostatics

Implementation Method 2

utilizing contact electrification or inter-metallic bonding for secure clamping in low-pressure environments

Methodology Applied

Scientific EffectContact electrification: Triboelectric Effect

Data Source

PatentUS12422759B2Component for use in a lithographic apparatus, method of protecting a component and method of protecting tables in a lithographic apparatus

Publication Date: 2025.09.23 ASML NETHERLANDS BV

AI summary

A method of protecting a component of a lithographic apparatus, the method including the steps of: providing a protective cover which is shaped to protect at least part of said component, the protective cover having a contact surface which is arranged to adhere to a first surface of at least part of said lithographic apparatus or said component; and bringing the protective cover into proximity with the component so as to cause the contact surface to adhere to the lithographic apparatus or said component and remain adhered without the application of external force. It is also provided a patterning device for use in a lithographic apparatus and a lithographic apparatus.