Wafer Chucking with Ring Frame Compression for Warped Wafer Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wafer chucking technologies fail to accurately fix warped wafers using vacuum chucks, as they may not provide sufficient downward compression and alignment, potentially damaging the wafer during the process.
Innovation Solution
The apparatus employs a combination of a vacuum chuck, clampers that directly compress the ring frame in a vertical direction, and alignment blocks or a robot to accurately align the wafer, ensuring the wafer is flattened and securely fixed without direct contact that could cause damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a vacuum chuck is used to fix the wafer, then the wafer can be held in place, but warped wafers cannot be accurately fixed or flattened
Solution Approach 1:
The patent introduces a ring frame as an intermediary component between the vacuum chuck and the wafer. The ring frame is attached to the outer periphery of the wafer using an adhesive layer, and the clampers compress the ring frame to indirectly flatten and secure the wafer, resolving the contradiction between holding the wafer in place and achieving flatness.
Solution Approach 2:
The patent divides the wafer handling system into separate functional components: the vacuum chuck for holding, the ring frame for structural support and alignment, and the clampers for compression. This segmentation allows each component to perform its specific function optimally without compromising the others.
2Manufacturing precision
If clampers are used to compress the wafer directly, then the wafer can be flattened, but the wafer may be damaged
Solution Approach 1:
The ring frame serves as a protective intermediary between the clampers and the wafer. The clampers compress the ring frame, which in turn applies gentle pressure to the wafer through the adhesive layer, achieving flatness without direct contact that could cause damage.
Solution Approach 2:
The adhesive layer is applied to the ring frame in advance, creating a cushioning interface before the compression action occurs. This preliminary preparation ensures that the subsequent compression by the clampers is distributed evenly and does not concentrate stress on specific points of the wafer.
3Manufacturing precision
If the wafer is compressed to flatten it, then alignment can be improved, but the wafer may shift or misalign horizontally
Solution Approach 1:
The alignment blocks act as intermediaries that guide the ring frame horizontally during compression. These blocks prevent the ring frame (and thus the wafer) from shifting laterally while allowing vertical compression, ensuring stable alignment throughout the flattening 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
This solution allows for precise alignment and firm fixation of warped wafers without damaging them, ensuring accurate chucking and preventing wafer damage during the cutting process.
Implementation Method 1
a vacuum chuck arranged under the wafer with a ring frame to fix the wafer using vacuum
Data Source
AI summary
An apparatus for chucking a wafer, the apparatus including a vacuum chuck arranged under the wafer with a ring frame to fix the wafer using vacuum, a plurality of clampers directly making contact with the ring frame to downwardly compress the ring frame in a vertical direction, and a plurality of alignment blocks pushing the ring frame toward a central portion of the wafer in a horizontal direction to align the wafer.