Vertical Wafer Rotation in Wet Processing Tanks for Uniform Etching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor manufacturing devices face challenges in achieving in-plane uniformity of processing on wafers due to differences in processing solution temperature, etchant concentration, and flow rate, which result in uneven etching across the wafer surface.
Innovation Solution
The semiconductor manufacturing apparatus incorporates a processing tank with a first and second belt conveyor system that supports and rotates the wafer vertically within the tank, ensuring uniform exposure to the processing solution by dispersing the impact points of the solution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the processing solution is discharged from a jet tube and circulated in a processing tank, then the processing solution can be efficiently delivered to the wafer, but the temperature, concentration, and flow rate of the processing solution become non-uniform near the jet tube outlet, resulting in non-uniform etching across the wafer surface
Solution Approach 1:
The wafer is rotated during processing to dynamically change its position relative to the jet tube outlet. This rotation ensures that different regions of the wafer surface are exposed to the processing solution at different times, averaging out the non-uniformities in temperature, concentration, and flow rate that occur near the jet tube outlet, thereby achieving uniform etching across the entire wafer surface
Solution Approach 2:
The invention introduces rotational motion in the angular dimension around the wafer center. By rotating the wafer about its central axis, the system transforms a static exposure problem into a dynamic one, where the temporal variation in solution properties is converted into spatial uniformity across the wafer surface through continuous angular movement
Data Source
AI summary
The semiconductor manufacturing apparatus according to the embodiment includes a processing tank that stores a processing solution for processing wafers and circulates the stored processing solution, a first belt conveyor arranged to extend vertically within the processing tank, a second belt conveyor arranged to extend vertically within the processing tank, and a drive controller that opens and closes the first and second belt conveyors to sandwich and support ends of the wafers, and controls the first and second belt conveyors to rotate.