摘要 |
A system, and methods of its use, for characterizing semiconductor wafers with enhanced S parameter contour mapping employ small signal scatter parameter measurements of a representative sample of die to create a contour map of a wafer surface. Those die which fail to meet performance specifications are marked as bad die before the wafer is sent to a back-end process, where the unmarked good die are extracted and assembled into working products. By using enhanced S parameter mapping for characterizing the die, only those die marked as bad die need be discarded. Thus, instead of scrapping an entire wafer die lot based on the failure of a single die from that wafer, the wafer sort yield may be dramatically increased. The increased in wafer sort yield in turn, increases total production yield. |