Probe Card Alignment via Camera-Based Positioning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge is to easily attach and detach probe cards from a transfer stage in wafer inspection apparatuses, where reducing the gap between positioning pins and pin holes leads to difficulties due to pin entrapment, necessitating improved alignment methods.
Innovation Solution
A method utilizing cameras to determine reference positions and distances for aligning probe cards with attaching units on the transfer stage, eliminating the need for positioning pins or pin holes by ensuring accurate alignment and secure attachment through vacuum attraction and supporting members.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the gap between positioning pin and pin hole is reduced to improve positioning accuracy, then the positioning accuracy is improved, but the positioning pin is caught by the side surface of the pin hole making it difficult to attach/detach probe card
Solution Approach 1:
The patent removes the positioning pin and pin hole structure entirely from the system. Instead of using mechanical positioning features, the probe card is positioned and held in place solely by vacuum attraction between the probe card holder and the probe card base, eliminating the interference between positioning pin and pin hole side surfaces
Solution Approach 2:
The patent employs vacuum attraction (a pneumatic principle) to both position and secure the probe card. The vacuum force acts uniformly across the contact surface between the probe card holder and probe card base, providing both positioning and holding functions without requiring mechanical positioning features that cause interference
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
This method allows for easy and accurate attachment and detachment of probe cards without the need for positioning pins or pin holes, enhancing the reliability and efficiency of the process.
Implementation Method 1
the probe card is brought into contact with the probe card attaching unit through vacuum attraction
Data Source
AI summary
A probe card attaching method makes it easy to attach/detach a probe card to/from a transfer stage. In a wafer inspection apparatus 10, a reference position is determined by moving a transfer stage 18 to align a stage-side camera 28 with a tester-side camera 16 in a tester 15, a first distance from the reference position to a center of a pogo frame 19 in the tester 15 is determined by checking a pin mark 24 in the tester 15 with the stage-side camera 28, a second distance from the reference position to a center of a probe card 20 is determined by checking a target mark 32 in the probe card 20 with the tester-side camera 16. Then, the transfer stage 18 is moved to allow the probe card 20 to face the pogo frame 19 based on the reference position, the first distance, and the second distance.