High-Speed Probe Card Analysis

Probe cards represent an indispensable component in wafer testing processes. Due to their frequent contacts with wafer pads, the physical condition of probe cards needs to be closely monitored and analyzed to maintain the integrity of testing. This paper proposes a new vision-based probe card analysis technique that can be applied to a situation where the vision system is continuously running to take moving images for fast inspection. The approach taken in this paper is to operate the machine vision in time synchrony with the position sensing and to restore the blurred pixel data with the image restoration technique. The main concepts are demonstrated using an experimental test bed and a commercial probe card. Compared to the existing stop-and-go approach, the proposed technique can substantially enhance the inspection speed without additional cost for major hardware change.