Surface characterization of semiconductors with plasma and thermal waves analysis

Abstract

The well characterized (100)-Si surface is used to demonstrate the capacity of the noncontact measurement of surface recombination velocity of excess carriers using photothermal heterodyne spectroscopy. The oxidized silicon surface is cleaned by an electron irradiation or by excimer laser in ultrahigh vacuum (UHV). The beam induced desorption and changes of surface binding states are monitored by Auger electron spectroscopy (AES). During the surface processing in UHV the sample is in situ excited by laser irradiation. The modulated reflectivity is recorded and change carrier and thermal wave analysis are carried out to measure the change of the surface recombination velocity. The influence of ion implantation and annealing on surface recombination velocity are monitored. © 1995.