Wafer level tracking and control to full mini-environment line

This paper addresses wafer level tracking as the key technology to achieve higher productivity in a full mini-environmentalized (M-E) manufacturing line. Texas Instruments has developed and installed the M-E and wafer level tracking control system for the new 8 inch line in Dallas and transferred the same concept to new 8 inch lines in other fabs. The wafer level tracking (WLT) system established the following: elimination of 100% of wafer scraps caused by mishandling by manufacturing technician; retention of the same working productivity in the M-E line as in legacy lines using open cassettes; provision of tracking data for wafer level fault detection. The approach, issues and achievements are discussed in this paper.