Generation of electron-acoustic signals and distribution of potential in transistor chip under applied of bias

An observation area was first selected using scanning electron microscopy (SEM)-mode images. Switching to an electron-acoustic microscopy (EAM)-mode, the area selected from SEM images was then studied with EAM images using electron-acoustic signals. We carried out nondestructive internal observation at the fixed area of an Si transistor chip put into operation by application of bias voltage ( V b ) in situ by EAM. The results showed that (a) the distribution of potential caused by V b application in the chip could be determined nondestructively from the change in the contrast of EAM images and (b) the internal structure of devices in operation could be observed nondestructively by EAM.