Wafer Scratches

Problem description:

Process equipment scratches the back side of the wafers.  Vast engineering efforts were made without finding the root cause.

InnerSense Solution:

Using SmartWafer  a Wafer Handling Analyzer the customer found that the equipment robot arm touches the wafer every time it goes in. The upper chart shows a peak each time that the arm touches the wafer. The lower chart shows normal behaviour of a robot arm. Finding the root cuase of the wafer breakage caused the customer to adopt the methodology of High Precision Maintenance (HPM)