Wafer Centering Hardware Design for Edge Cut Precision

Solution Overview

Problem

Current semiconductor wafer manufacturing processes face challenges in achieving precise wafer edge cut accuracy and symmetry during photo resist application, leading to variations in edge bead removal (EBR) and asymmetrical distribution of photo resist, which affect the quality and yield of semiconductor wafers.

Innovation Solution

A system and method for positioning a semiconductor wafer on a rotatable chuck using a sensor light and detector to calculate and adjust the wafer's position based on rotatable chuck coordinate information, ensuring precise alignment of the wafer's center coordinates with the chuck's center coordinates, thereby improving EBR accuracy and symmetry.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If conventional wafer positioning methods are used, then the manufacturing process is simple, but the wafer edge cut accuracy and photo resist distribution symmetry are poor

Engineering Contradiction:

Improvewafer edge cut accuracyVSAvoidpositioning system complexity

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The system performs preliminary wafer positioning and alignment before the main photo resist application process. The sensor detector captures wafer position information in advance, calculates the required adjustments, and pre-positions the wafer on the rotatable chuck, ensuring accurate alignment is established before manufacturing operations begin.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The positioning system uses sensor detectors to continuously monitor wafer position and provides feedback to the control system. The calculated position information is used to adjust the wafer placement on the rotatable chuck, creating a closed-loop control system that ensures precise alignment and symmetry during photo resist distribution.

Inventive Principle:

Principle #23Feedback

2Stability of the object's composition

If conventional wafer positioning methods are used, then the manufacturing process is simple, but the photo resist distribution symmetry is poor

Engineering Contradiction:

Improvephoto resist distribution symmetryVSAvoidpositioning system complexity

Core Design Contradiction:

Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The system performs preliminary wafer positioning and alignment before the main photo resist application process. The sensor detector captures wafer position information in advance, calculates the required adjustments, and pre-positions the wafer on the rotatable chuck, ensuring accurate alignment is established before manufacturing operations begin.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The positioning system uses sensor detectors to continuously monitor wafer position and provides feedback to the control system. The calculated position information is used to adjust the wafer placement on the rotatable chuck, creating a closed-loop control system that ensures precise alignment and symmetry during photo resist distribution.

Inventive Principle:

Principle #23Feedback

3Measurement precision

If precise wafer positioning is implemented, then edge bead removal accuracy is improved, but measurement and detection complexity increases

Engineering Contradiction:

Improvewafer position measurement precisionVSAvoidwafer position detection difficulty

Core Design Contradiction:

Measurement precisionVSDifficulty of detecting and measuring

Solution Approach 1:

The system replaces complex mechanical measurement and alignment mechanisms with optical sensing technology. Sensor detectors use light-based measurement to determine wafer position information, which is then processed by a control system to calculate precise positioning adjustments, eliminating the need for complex mechanical measurement devices.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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 enhances the precision and symmetry of wafer edge cuts, reducing defects and improving the effectiveness and yield of semiconductor wafer manufacturing by ensuring consistent and accurate edge bead removal and photo resist distribution.

Implementation Method 1

a sensor light positioned proximate to the rotatable chuck, a sensor detector positioned proximate to the rotatable chuck. The sensor detector is operable to determine wafer position information.

Methodology Applied

Scientific EffectLight detection: Light

Data Source

PatentUS9082802B2Wafer centering hardware design and process

Publication Date: 2015.07.14 MACRONIX INTERNATIONAL CO LTD

AI summary

An apparatus, system, or method for positioning a wafer on a support of a rotatable chuck may improve the accuracy and precision of various wafer edge cuts and wafer profiling at a variety of stages of wafer manufacturing. The apparatus, system, or and/or method may employ one or more of a wafer position calculator to calculate a desired wafer position and to provide desired wafer position information to a wafer arm controller; and a wafer arm controller in communication with the wafer position calculator to provide instructions to adjust a wafer arm to position the wafer on the support according to the desired wafer position. Various sensor detectors and sensor lights or other mechanisms for sensing the position of a wafer may also be used.