Nondestructive Profiling of Transistor-Chip under Bias Application by Electron-Acoustic Microscopy

In electron-acoustic microscopy (EAM), the electron acoustic signal was amplified with a two-phase lock-in amplifier and the phase signal was calculated from the two-output (in-phase and out-phase) signals of the amplifier using a personal computer. Nondestructive profiling of an Si transistor-chip (Tr-chip) under bias application was attempted by EAM using the phase images (PhIs) obtained. It was found that (a) dislocation lines were presented in the base layer which underlay the surface Al electrode (3 µm thick) of the specimen, and (b) PhI changed with bias conditions. The distribution of dislocation lines was investigated.