DETECTION OF SOI FATAL DEFECTS BY CU DECORATION IN CONJUNCTION WITH HF IMMERSION

摘要

New Cu decoration method in conjunction with HF immersion is developed for its efficient line monitoring in SOI wafer production. This is able to detect pinholes in both a top Si layer and a buried oxide layer in the identical wafers by visual inspection. It becomes possible to count the genuine pinholes correctly by eliminating the high concentration of copper decoration near the edge which is induced by current leakage by a penetration of HF solution into the wafer edge. As a result, the pinhole density is measured and confirmed less than 0.05/cm~2 in ELTRAN~(~R) SOI wafers by using this method.