Transparent Chuck Table Imaging for Metallic-Backed Wafers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing processing apparatuses face challenges in imaging the top surface of a wafer when a metallic layer is present on the undersurface, leading to difficulties in detecting processing regions and requiring increased apparatus size due to the need for additional moving and rotating mechanisms.
Innovation Solution
A processing apparatus with a chuck table formed by a transparent body, an angle control mechanism, and an imaging unit positioned to image through the transparent holding member without overlapping with the supporting member, allowing for miniaturization and reduced installation area by eliminating the need for separate horizontal movement of the imaging unit.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If an infrared lamp is used to image the top surface of the wafer through the chuck table, then imaging is enabled even when the top surface is covered, but imaging is obstructed when a metallic layer is present on the undersurface
Solution Approach 1:
The patent introduces a transparent holding member as an intermediary between the wafer and the imaging system. This holding member allows optical signals to pass through while enabling the imaging unit to capture images of the wafer's top surface from below the chuck table, bypassing the obstruction caused by metallic layers on the wafer's undersurface
Solution Approach 2:
The patent changes the imaging dimension by positioning the imaging unit below the chuck table to image through the transparent holding member, rather than attempting to image from above when the surface is covered. This dimensional shift allows imaging to occur through the transparent holder without being blocked by metallic layers on the wafer
2Volume of stationary object
If imaging means is disposed on the lower side of the chuck table to image through the transparent holding member, then apparatus size is reduced, but the imaging unit must be precisely positioned without overlapping with the supporting member
Solution Approach 1:
The patent segments the chuck table structure into a transparent holding member and a supporting member, with the imaging unit positioned to image through the holding member while avoiding overlap with the supporting member. This segmentation allows for compact apparatus design while maintaining clear imaging paths
Solution Approach 2:
The patent applies local quality by making the holding member transparent in the region where imaging occurs, while the supporting member can have different properties. The imaging unit is positioned in a specific location where it can image through the transparent holding member without interference from the supporting member, requiring precise positioning
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
Enables effective imaging of the top surface of the wafer even with metallic layers, reducing the apparatus size and installation area, while maintaining precise positioning and processing capabilities.
Implementation Method 1
a chuck table formed by a transparent body, an angle control mechanism, and an imaging unit positioned to image through the transparent holding member
Data Source
AI summary
A workpiece processing method for processing a workpiece using a processing apparatus including a chuck table, a processing unit, a moving mechanism for moving the chuck table and the processing unit relative to each other, and an imaging unit for imaging the workpiece, where the chuck table includes a holding member formed by a transparent body and a supporting member supporting a part of the holding member and connected to an angle control mechanism. The method includes a tape affixing step, a holding step of holding the workpiece by the chuck table via the tape, and an identifying step of imaging the top surface side of the workpiece through the transparent holding member by the imaging unit positioned in a region that is on a lower side of the holding member and is not superimposed on the supporting member, and identifying a region to be processed in the workpiece.