Bevel Etcher Vacuum Chuck Substrate Curvature Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
During the processing of semiconductor substrates, the accumulation of byproduct layers on the bevel edge leads to weakened bonds and potential contamination when these layers peel off, especially during substrate transport, due to uneven plasma etching density.
Innovation Solution
A vacuum chuck arrangement with a support ring and recessed surface is used in a bevel etcher, which includes a plasma cleaning mechanism to etch the bevel edge, maintaining a vacuum force and using process gases to remove buildup, thereby reducing curvature and preventing contamination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If plasma etching is performed on the bevel edge, then the byproduct layers are removed, but the plasma density is lower near the edge resulting in accumulation of byproduct layers
Solution Approach 1:
The patent introduces a localized plasma generation source (ring electrode or linear electrode) positioned specifically at the bevel edge region to provide enhanced plasma density where it is most needed. This local quality enhancement ensures uniform etching across the bevel edge while preventing byproduct accumulation in this critical area.
2Productivity
If multiple etch processes are performed, then the substrate is processed, but the byproduct layers accumulate and bonds weaken causing peeling and contamination
Solution Approach 1:
The patent performs plasma cleaning of the bevel edge either before or between etch processes as a preliminary action. This prevents byproduct accumulation from occurring in the first place, maintaining substrate integrity throughout multiple processing steps and preventing contamination during substrate transport.
3Productivity
If the bevel edge is not cleaned, then processing is faster, but contamination occurs during substrate transport
Solution Approach 1:
The patent implements continuous or periodic plasma cleaning of the bevel edge throughout the processing sequence, ensuring the edge remains clean during substrate transport and between etch steps. This continuous action maintains substrate integrity without significantly impacting overall processing throughput.
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 substrate curvature and prevents contamination by ensuring consistent plasma etching across the bevel edge, maintaining the substrate's integrity and cleanliness during processing.
Implementation Method 1
a source of vacuum in fluid communication with the space, the vacuum source being adapted to establish a vacuum force which holds the substrate in place on the support ring
Implementation Method 2
a plasma generation unit adapted to energize process gas into a plasma state in the vicinity of the bevel edge and a source of vacuum in fluid communication with the space
Implementation Method 3
energizing process gas into a plasma state and removing buildup on the bevel edge by etching the buildup with the plasma
Data Source
AI summary
A bevel etcher incorporating a vacuum chuck used for cleaning the bevel edge and for reducing the bending curvature of a semiconductor substrate. The bevel etcher includes a vacuum chuck and a plasma generation unit which energizes process gas into a plasma state. The vacuum chuck includes a chuck body and a support ring. The top surface of the chuck body and inner periphery of the support ring form a vacuum region enclosed by the bottom surface of a substrate mounted on the support ring. A vacuum pump evacuates the vacuum region during operation. The vacuum chuck is operative to hold the substrate in place by the pressure difference between the top and bottom surfaces of the substrate. The pressure difference also generates a bending force to reduce the bending curvature of the substrate.