Dynamic Peeling Angle Wafer Sheet Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing sheet peeling methods for semiconductor wafers with protection sheets and bumps cause adhesive residue and stress-induced damage due to continuous peeling force, leading to cracks and adhesive residue on the wafer surface.
Innovation Solution
A sheet peeling apparatus with a movable peeling unit that forms an initial peeling angle along the wafer surface and transitions to a subsequent smaller angle, using a peeling tape bonded and wound to minimize load on the wafer and prevent adhesive residue, with a distance adjusting unit to manage peeling force.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a large peeling angle (near 180 degrees) is maintained throughout the peeling process, then cracks on the wafer are prevented, but adhesive remains among the projecting portions (bumps)
Solution Approach 1:
The peeling angle is made dynamic rather than static. The apparatus transitions from an initial large peeling angle (near 180 degrees) to a subsequent smaller peeling angle. This dynamic adjustment allows the system to first prevent cracks during initial peeling, then effectively remove adhesive from bump areas in the subsequent phase.
Solution Approach 2:
The initial large peeling angle serves as a preliminary action to safely initiate peeling without causing cracks. Once this preliminary phase is complete, the system transitions to the second phase with a smaller peeling angle that is optimized for complete adhesive removal from the bump areas.
2Productivity
If continuous press force is applied during peeling, then the sheet is peeled off effectively, but the wafer is damaged due to induced load
Solution Approach 1:
The press force is applied periodically rather than continuously. The apparatus includes a press force application phase followed by a release phase. This periodic action maintains peeling efficiency during the force application phase while preventing wafer damage during the release phase when the load is removed.
Solution Approach 2:
The press force transitions from static continuous application to dynamic periodic application. The system adjusts the press force magnitude and timing to optimize peeling efficiency while minimizing harmful loads on the wafer structure.
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 effectively peels off protection sheets without leaving adhesive residue on the wafer, reducing stress and damage by adjusting peeling angles and forces, ensuring minimal load on the wafer during the peeling process.
Implementation Method 1
a peeling tape paid out from the sheet peeling unit is bonded to the sheet
Data Source
AI summary
A peeling apparatus 10 includes a peeling table 11 supporting a wafer W on which a sheet S is stuck and a sheet peeling unit 12 disposed above the peeling table 11, in which sheet S can be peeled off with relative movement of the sheet peeling unit 12 and the peeling table 11. The peeling apparatus 10 includes a support roll 20 of peeling tape PT, first and second rolls 30, 31 bonding the peeling tape PT to the sheet S surface, and a winding roll 21 of the peeling tape PT. Peeling-off is performed in a state of forming an initial peeling angle a1 such that a peeling tape PT is folded in an aperture C formed between the second roll 31 and the sheet S, and afterwards the sheet S is peeled off at subsequent peeling angle a2 corresponding to a diameter of the second roll 31.