Semiconductor Wafer Edge Thickness Profiling for Crack-Safe Spin Etching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor substrate processing methods face challenges in achieving uniform thickness and preventing wafer cracking, particularly for large-diameter wafers, during grinding and spin etching processes.
Innovation Solution
A manufacturing method that involves grinding the first surface of the semiconductor substrate to form an outer peripheral surplus region and then performing spin etching, where the thickness of the substrate is made non-uniform by forming a slope portion to ensure uniformity and reduce the need for high-speed rotation, thereby preventing wafer breakage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If high-speed rotation is used in spin etching to achieve uniform thickness, then etching uniformity is improved, but wafer cracking risk increases
Solution Approach 1:
The method performs preliminary grinding to form an outer peripheral surplus region with increased thickness before spin etching. This pre-prepared thicker region serves as a reinforcement that prevents wafer cracking during subsequent high-speed spin etching, while the gradient structure ensures uniform etching across the wafer surface.
Solution Approach 2:
The invention creates a non-uniform thickness distribution with a gradient structure, where the outer peripheral region has greater thickness than the center region. This local variation in thickness provides targeted reinforcement at the periphery without affecting the central device region, resolving the contradiction between uniformity and cracking prevention.
2Manufacturing precision
If uniform thickness is achieved through conventional grinding, then dimensional consistency is improved, but spin etching requires high-speed rotation increasing breakage risk
Solution Approach 1:
The invention intentionally creates a non-uniform thickness distribution with a gradient structure, where the outer peripheral region has greater thickness than the center region. This local variation in thickness provides targeted reinforcement at the periphery without affecting the central device region, resolving the contradiction between uniformity and cracking prevention.
Solution Approach 2:
The method performs preliminary grinding to form an outer peripheral surplus region with increased thickness before spin etching. This pre-prepared thicker region serves as a reinforcement that prevents wafer cracking during subsequent high-speed spin etching, while the gradient structure ensures uniform etching across the wafer surface.
3Strength
If the outer peripheral surplus region is formed with larger width, then reinforcement effect is improved, but manufacturing complexity increases
Solution Approach 1:
The invention controls the width of the outer peripheral surplus region within a specific range (1mm to 5mm) to optimize the reinforcement effect while maintaining manufacturing simplicity. This parameter optimization ensures sufficient strength without excessive complexity in the grinding process.
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 method achieves uniform thickness and reduces the risk of wafer cracking by allowing low-speed spin etching, enhancing processing stability and preventing damage to large-diameter wafers.
Implementation Method 1
grinding the first surface of the semiconductor substrate to form an outer peripheral surplus region
Implementation Method 2
performing spin etching, where the thickness of the substrate is made non-uniform by forming a slope portion to ensure uniformity and reduce the need for high-speed rotation
Data Source
AI summary
Provided is a manufacturing method of semiconductor apparatus comprising a semiconductor substrate, the method comprising: grinding a first surface of the semiconductor substrate to form an outer peripheral surplus region on an outer periphery of the semiconductor substrate; and spin etching the first surface of the semiconductor substrate by a chemical liquid, and wherein after the grinding, in a region of the semiconductor substrate which is closer to an inner side than the outer peripheral surplus region, a thickness of the semiconductor substrate in an end portion of the region is greater than a thickness of the semiconductor substrate in a center portion of the region.