Wafer Dividing Apparatus Vibration Control
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Solution Overview
Problem
Existing wafer dividing methods, particularly those using dicing tape expansion, face challenges in accurately and efficiently dividing wafers along reduced-strength streets due to random tensile forces, leading to irregular divisions and productivity issues.
Innovation Solution
A wafer dividing apparatus that includes a frame holding mechanism, a wafer holding table with vibration generating means, and tape expanding means to apply controlled vibration and expansion of the dicing tape perpendicular to the wafer, ensuring precise division along reduced-strength streets.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If dicing tape is expanded to apply tensile force to divide the wafer, then the wafer can be divided along the streets, but the tensile force is applied in random directions causing irregular division
Solution Approach 1:
The patent applies vibration to the wafer during the division process. The vibration generates ultrasonic waves that concentrate energy at the street lines where the wafer strength is reduced, enabling precise and consistent division along the desired paths while avoiding irregular breaks caused by random tensile forces.
Solution Approach 2:
The patent changes the physical state and properties of the wafer by applying vibration energy. This alters the stress distribution and energy concentration at the street lines, transforming the division process from one governed by random tensile forces to one controlled by concentrated vibrational energy at specific locations.
2Strength
If a thick cutting blade is used to cut the wafer, then cutting is more robust, but the street width must be increased reducing productivity
Solution Approach 1:
The patent replaces the mechanical cutting system (thick cutting blade) with a vibration-based division system. Instead of using mechanical force to fracture the wafer through a thick blade, the invention uses ultrasonic vibration to concentrate energy at the street lines, achieving division with minimal material removal and narrower street widths.
Solution Approach 2:
The vibration-based division method concentrates energy at the street lines where the wafer is already weakened, enabling division without requiring thick cutting blades. This reduces the necessary street width from about 50 μm to much narrower dimensions, thereby increasing the ratio of device area to street area and improving productivity.
3Manufacturing precision
If laser processing is used to form modified layers along streets, then the wafer strength is reduced for division, but the division process becomes more complex
Solution Approach 1:
The patent combines the laser processing step (for forming modified layers) with the vibration division step into an integrated process. The laser-prepared streets with reduced strength serve as ready-made pathways for the subsequent vibration division, merging two previously separate operations into a coordinated sequence that simplifies the overall 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 apparatus enables accurate, reliable, and efficient division of wafers along multiple streets by applying controlled vibration to the wafer holding table, ensuring consistent and precise separation of individual devices while maintaining productivity.
Implementation Method 1
vibration generating means for applying vibration to the holding surface of the wafer holding table
Data Source
AI summary
A wafer dividing apparatus for dividing a wafer along a plurality of crossing streets in the condition where the wafer is attached to the upper surface of a dicing tape supported to an annular frame and the strength of the wafer is reduced along the streets. The wafer dividing apparatus includes a frame holding unit for holding the annular frame, a wafer holding table having a holding surface for holding the wafer through the dicing tape supported to the annular frame held by the frame holding unit, a tape expanding unit for relatively moving the frame holding unit and the wafer holding table in a direction perpendicular to the holding surface of the wafer holding table to thereby expand the dicing tape, and a vibration generating unit for applying vibration to the holding surface of the wafer holding table.