Multi-aperture plate thermal management for charged particle beam exposure

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional charged particle beam exposure systems using multi-aperture plates face performance issues due to inhomogeneous deformation and distorted patterns caused by temperature-induced internal stress, which affects the accuracy and reliability of pattern formation on substrates.

Innovation Solution

A beam manipulating arrangement with a multi-aperture plate and a frame portion, where heaters are thermally coupled to the frame to evenly distribute temperature changes, reducing internal stress and using varying heat emissivity and radiation cooling to manage temperature gradients, and incorporating a protective plate with a gap to minimize mechanical contact and stress.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If heaters are thermally coupled to the central portion of the multi-aperture plate, then temperature control is improved, but inhomogeneous deformation and pattern distortion worsen

Engineering Contradiction:

Improvetemperature controlVSAvoidpattern accuracy

Core Design Contradiction:

TemperatureVSManufacturing precision

Solution Approach 1:

The multi-aperture plate is divided into two distinct portions: a central portion that defines the apertures and a frame portion that surrounds it. The heater is thermally coupled only to the frame portion, not the central portion. This segmentation allows differential thermal management where the frame can be heated for stress control while the central portion maintains its temperature independently, preventing inhomogeneous deformation of the aperture-defining region.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different portions of the multi-aperture plate are given different thermal properties and treatments. The frame portion is equipped with heaters for active temperature control, while the central portion is designed with specific thermal characteristics to minimize deformation. This local differentiation ensures that temperature control needs are met without compromising the dimensional stability of the critical aperture region.

Inventive Principle:

Principle #3Local quality

2Stability of the object's composition

If the multi-aperture plate is heated uniformly, then internal stress is reduced, but temperature gradients and energy consumption increase

Engineering Contradiction:

Improveinternal stressVSAvoidenergy consumption

Core Design Contradiction:

Stability of the object's compositionVSUse of energy by moving object

Solution Approach 1:

Instead of heating the entire multi-aperture plate uniformly, heating is applied partially and selectively only to the frame portion. This partial action is sufficient to reduce internal stresses in the plate structure without the excessive energy consumption that would result from heating the entire plate, including the central aperture-defining region.

Inventive Principle:

Principle #16Partial or excessive action

3Stability of the object's composition

If mechanical contact between plates is increased, then structural stability is improved, but stress and deformation worsen

Engineering Contradiction:

Improvestructural stabilityVSAvoiddeformation

Core Design Contradiction:

Stability of the object's compositionVSManufacturing precision

Solution Approach 1:

A flexible or compliant layer is introduced between the multi-aperture plate and the protective plate. This layer acts as a stress-absorbing interface that allows the plates to maintain their relative positions and structural stability while accommodating thermal expansion and contraction differences, thereby preventing stress transmission that would cause deformation of the aperture patterns.

Inventive Principle:

Principle #30Flexible shells and thin films

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 solution effectively reduces temperature gradients and internal stress, maintaining the accuracy and reliability of pattern formation by ensuring uniform temperature distribution and minimizing deformation, thus enhancing the performance of charged particle beam exposure systems.

Implementation Method 1

at least one heater thermally coupled to the frame portion of the multi-aperture plate

Methodology Applied

Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

allows to introduce a rise of temperature also in the frame portion of the multi-aperture plate such that changes of internal stress, such as tensile or compressive stress, in the multi-aperture plate are reduced

Methodology Applied

Scientific EffectThermal expansion: Thermal Expansion

Implementation Method 3

using varying heat emissivity and radiation cooling to manage temperature gradients

Methodology Applied

Scientific EffectThermal radiation: Thermal Radiation

Data Source

PatentUS8368030B2Charged particle beam exposure system and beam manipulating arrangement

Publication Date: 2013.02.05 CARL ZEISS SMT GMBH

AI summary

A beam manipulating arrangement for a multi beam application using charged particles comprises a multi-aperture plate having plural apertures traversed by beams of charged particles. A frame portion of the multi-aperture plate is heated to reduce temperature gradients within the multi-aperture plate. Further, a heat emissivity of a surface of the multi-aperture plate may be higher in some regions as compared to other regions in view of also reducing temperature gradients.