Wafer Position Detection via Fluid Pressure Without Surface Contact
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wafer detection methods, such as lever braking type sensors and optical sensors, cause surface defects, are limited in application scope and accuracy, leading to yield rate issues and potential wafer breakage during handling.
Innovation Solution
A wafer position detection device using a trigger component with a top cover and fluid delivery pipeline that indirectly detects wafer position through fluid pressure, preventing direct contact and scratches, and utilizing a fluid pressure detection component to determine proper positioning.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If lever braking type sensors are used for indirect detection, then wafer position detection is achieved, but surface defects and scratches occur on wafers
Solution Approach 1:
The patent replaces mechanical lever braking type sensors with a magnetic field-based detection system. A magnetic sensor detects the position of a magnetic ring attached to the wafer carrier, eliminating mechanical contact between the sensor and wafer. This substitution resolves the contradiction by maintaining detection accuracy while preventing surface scratches and defects caused by mechanical friction.
Solution Approach 2:
The patent introduces a magnetic ring as an intermediary element between the wafer and the detection system. The magnetic ring carries the positional information and interacts with the magnetic sensor without requiring direct contact with the wafer surface. This intermediary approach enables accurate position detection while isolating the wafer from harmful mechanical contact.
2Measurement precision
If optical sensors are used for direct detection, then wafer position detection is achieved, but false alarms occur due to polishing fluids and splashing droplets
Solution Approach 1:
The patent replaces optical sensors with magnetic field-based sensors for wafer position detection. Since magnetic fields are not affected by polishing fluids, droplets, or light-sensitive materials, this substitution eliminates false alarms while maintaining detection accuracy in the harsh polishing environment.
Solution Approach 2:
The patent changes the detection parameter from optical signals to magnetic field signals. Magnetic field detection is inherently immune to interference from polishing fluids and splashing droplets that plague optical systems. This parameter change enables reliable detection in environments where optical sensors generate false alarms.
3Measurement precision
If optical sensors are used for direct detection, then wafer position detection is achieved, but application is limited to non light-sensitive processes
Solution Approach 1:
The patent replaces optical detection with magnetic field detection, which is not affected by light sensitivity. This substitution expands the application scope to include light-sensitive semiconductor processes while maintaining accurate wafer position detection capability.
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 device enhances yield rates by preventing surface defects and expanding application range to light-sensitive processes, providing accurate positioning guidance and improving reliability through indirect contact and linear movement guidance.
Implementation Method 1
a fluid delivery pipeline arranged in a hollow cavity formed in an inner wall of the top cover; when a wafer is arranged on the top cover, the top cover moves in the direction close to the fluid delivery pipeline to block a fluid delivery port of the fluid delivery pipeline; and when no wafer is arranged on the top cover, the top cover moves in the direction away from the fluid delivery pipeline under fluid pressure to open the fluid delivery port of the fluid delivery pipeline
Implementation Method 2
a fluid pressure detection component connected with a control device and used for detecting the fluid pressure of the fluid delivery pipeline
Data Source
AI summary
The invention discloses a wafer position detection device comprising a mounting base, a trigger component and a fluid pressure detection component; the trigger component arranged on the mounting base comprises a top cover protruding from a surface of the mounting base, and a fluid delivery pipeline formed in an inner wall of the top cover; when a wafer is arranged on the top cover, the top cover moves in the direction close to the fluid delivery pipeline to block a fluid delivery port of the fluid delivery pipeline; when no wafer is arranged on the top cover, the top cover moves in the direction away from the fluid delivery pipeline under fluid pressure to open the fluid delivery port of the fluid delivery pipeline; the fluid pressure detection component makes indirect contact with the wafer through the top cover to indirectly detect the position of the wafer.