Wafer Centering Device Pneumatic Pusher Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Wafer centering errors during measurement lead to high error rates and reduced operation efficiency in CMP equipment, as wafers often fail to be properly aligned with measuring apparatuses.
Innovation Solution
A wafer centering device comprising a body unit, guide unit with a support part and through-hole, and a displacement unit with actuators and a returning member, which uses air flow to move a pusher within the through-hole to center the wafer, ensuring accurate alignment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If wafers are processed without a centering device, then the device complexity is reduced, but the measurement precision deteriorates due to centering errors
Solution Approach 1:
A pusher component is introduced as an intermediary element between the actuator and the wafer. The pusher translates the actuator's linear motion into precise wafer positioning, mediating the interaction between the driving mechanism and the measured object to achieve accurate centering without complex direct coupling
Solution Approach 2:
The manual or complex mechanical centering adjustment is replaced with a pneumatic actuator system. Compressed air drives the piston-rod mechanism, substituting intricate mechanical linkages with a simpler pneumatic-driven system that achieves the same centering function with fewer moving parts
2Measurement precision
If a complex centering mechanism is used, then the measurement precision is improved, but the device complexity increases
Solution Approach 1:
The centering function is extracted as a separate, modular displacement unit with independent actuator, pusher, and returning member components. This extracted module can be independently designed, adjusted, and maintained without affecting the main measuring apparatus, simplifying the overall system while maintaining precision
Solution Approach 2:
The system uses adjustable parameters including air pressure control for the actuator, spring pre-load for the returning member, and geometric parameters of the guide holes to fine-tune the centering precision. By changing these parameters rather than redesigning the mechanism, optimal performance is achieved without increasing structural complexity
3Productivity
If manual centering adjustment is used, then the device complexity is reduced, but the productivity decreases due to high error rates
Solution Approach 1:
The centering system performs self-centering automatically through the actuator-pusher-spring mechanism without requiring external manual intervention. The wafer is inserted and the system autonomously positions it correctly, then automatically resets via the returning member, enabling continuous operation and improving productivity
Solution Approach 2:
The centering action is performed preliminarily before the measurement process begins. The actuator positions the wafer in the correct centered location in advance, ensuring that the subsequent measurement operation can proceed immediately without adjustment delays, thereby improving overall operation rate
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
Enhances the operation rate of CMP equipment by effectively centering wafers, reducing measurement errors and improving the precision of wafer width measurement.
Implementation Method 1
a returning member which allows the actuators to be elastically supported with respect to the body unit such that the actuators after operation thereof may return to an initial position
Implementation Method 2
a piston which is arranged in the cylinder and moves in the cylinder by the air
Data Source
AI summary
The present invention provides a wafer centering device for a measurement apparatus, the device comprising: a body unit; a guide unit which is installed in the body unit, has a support part for supporting a wafer, and has a through-hole and; and a displacement unit which is formed to be moved in the through-hole and has a pusher for moving the wafer on the support part.