Application of scanning transmission electron microscopy to semiconductor devices

Abstract

High voltage (500 kV) scanning transmission electron microscopy (STEM) has been applied for the first time to the observation of thinned silicon transistors of commercial type by using the transmission and conductive (electron-beam-induced conductivity) imaging modes. A high resolution image of crystal defects is obtained with the transmission signal and an image of the electric field region of the p-n junction is obtained with the conductive signal (either by intensity modulation or by Y-modulation). These two types of signals are sequentially or simultaneously recorded to produce an image that makes possible an unambiguous and highly-localized correlation between crystal defects and electrical properties of the thirmed semiconductor material. The great potential of STEM in the field of semiconductor devices is pointed out and demonstrated in particular cases.