Infrared surface analysis of semiconductors by a noncontact air gap ATR method

Characterization of chemical bonding structure of semiconductor surface is very important in order to develop a new surface treatment method. The air gap ATR method is presented, which gives al enhanced infrared absorption of surface chemical structure 40 times larger than conventional transmission, and is very useful to study the surface of materials with high refractive indices, such as semiconductors. The enhancement is attributable to the so-called optical cavity effect between the prism and the semiconductor samples. This technique is applied to the study of the mechanism of native oxide growth on a Si(100)substrate, H-terminated Si(lll) surfaces, and acid treated GaAs(001) surfaces.