Substrate Heating Unit with Segmented LED Zones

Solution Overview

Problem

Conventional substrate heating apparatuses suffer from non-uniform light intensity distribution, particularly on the edges and central regions of substrates during high-temperature chemical processing, which affects the etch rate and thermal uniformity.

Innovation Solution

A substrate processing apparatus with a heating unit featuring a disk-shaped heating plate divided into distinct zones, including central, peripheral, and intermediate zones, where heating modules with light-emitting diodes are arranged to emit light in different directions and angles, ensuring uniform heating by concentrating light on specific regions and using a heat rejection structure with fluid flow channels.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If IR lamps are arranged at equal intervals with the outermost lamp having a smaller size than the substrate and the innermost lamp having a specified size in view of a central nozzle, then the heating apparatus can be constructed with a simple and uniform structure, but the light intensity distributions on the edge and central region of the substrate rapidly fall, resulting in non-uniform heating

Engineering Contradiction:

Improveheating apparatus structureVSAvoidheating uniformity

Core Design Contradiction:

Device complexityVSTemperature

Solution Approach 1:

The heating apparatus is segmented into multiple independent heating zones along the substrate processing direction, with each zone containing IR lamps that can be independently controlled. This segmentation allows different regions of the substrate to receive customized heating, preventing the uniform structure from causing non-uniform heating. The first heating zone targets the edge region while the second heating zone targets the central region, resolving the contradiction between structural simplicity and heating uniformity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different heating characteristics are applied to different regions of the substrate. The first heating zone uses IR lamps configured for edge region heating, while the second heating zone uses IR lamps configured for central region heating. This local differentiation ensures that each region receives appropriate heating intensity, solving the problem of rapid light intensity fall-off in both edge and central regions that occurs with uniform lamp arrangement.

Inventive Principle:

Principle #3Local quality

2Ease of manufacture

If the outermost lamp has a smaller size than the substrate, then the lamp arrangement can be simplified, but the light intensity distribution on the edge region of the substrate rapidly falls

Engineering Contradiction:

Improvelamp arrangementVSAvoidedge region light intensity

Core Design Contradiction:

Ease of manufactureVSIllumination intensity

Solution Approach 1:

The heating apparatus is segmented into multiple independent heating zones along the substrate processing direction, with each zone containing IR lamps that can be independently controlled. This segmentation allows different regions of the substrate to receive customized heating, preventing the uniform structure from causing non-uniform heating. The first heating zone targets the edge region while the second heating zone targets the central region, resolving the contradiction between structural simplicity and heating uniformity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different heating characteristics are applied to different regions of the substrate. The first heating zone uses IR lamps configured for edge region heating, while the second heating zone uses IR lamps configured for central region heating. This local differentiation ensures that each region receives appropriate heating intensity, solving the problem of rapid light intensity fall-off in both edge and central regions that occurs with uniform lamp arrangement.

Inventive Principle:

Principle #3Local quality

3Adaptability or versatility

If the innermost lamp has a specified size in view of a central nozzle, then the central nozzle can be accommodated, but the light intensity distribution on the central region of the substrate rapidly falls

Engineering Contradiction:

Improvecentral nozzle accommodationVSAvoidcentral region light intensity

Core Design Contradiction:

Adaptability or versatilityVSIllumination intensity

Solution Approach 1:

The heating apparatus is segmented into multiple independent heating zones along the substrate processing direction, with each zone containing IR lamps that can be independently controlled. This segmentation allows different regions of the substrate to receive customized heating, preventing the uniform structure from causing non-uniform heating. The first heating zone targets the edge region while the second heating zone targets the central region, resolving the contradiction between structural simplicity and heating uniformity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

A reflective member is introduced as an intermediary element to redirect and concentrate light from the IR lamps toward the central region of the substrate. This reflective member compensates for the light intensity fall-off in the central region caused by the presence of the central nozzle, allowing the nozzle to be accommodated while maintaining adequate heating intensity in the central region.

Inventive Principle:

Principle #24Intermediary (Mediator)

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 achieves improved thermal uniformity across the substrate, reducing temperature deviations and enhancing the etch rate during high-temperature chemical processing.

Implementation Method 1

heating modules installed in respective heating zones on the heating plate that are divided from each other, each heating module having a printed circuit board on which heating light sources emitting light for heating are mounted

Methodology Applied

Scientific EffectLight emission for heating: Light

Implementation Method 2

heating light sources emitting light for heating

Methodology Applied

Scientific EffectThermal radiation: Thermal Radiation

Implementation Method 3

The heating plate may have a heat rejection structure with a fluid flow channel through which fluid flows, to reject heat generated by the heating modules

Methodology Applied

Scientific EffectHeat rejection through fluid flow: Convection

Data Source

PatentUS11569100B2Substrate heating unit and substrate processing apparatus having the same

Publication Date: 2023.01.31 SYSTEM ENGINEERING MEGA SOLUTION CO LTD

AI summary

The inventive concept relates to a substrate heating unit. The substrate heating unit includes a chuck stage having an inner space defined by a base and sidewalls, a heating unit provided in the inner space of the chuck stage, and a quartz window that covers the inner space of the chuck stage and has an upper surface on which the substrate is placed. The heating unit includes a heating plate having a disk shape with an opening in the center thereof and heating modules installed in respective heating zones on the heating plate that are divided from each other, each heating module having a printed circuit board on which heating light sources emitting light for heating are mounted.