THEORY OF SCANNING TUNNELING SPECTROSCOPY - APPLICATION TO SI(100)2X1 SURFACE

Presented is the theory of scanning tunneling microscopy (STM) based on the quasistationary states approach. The tunneling current is calculated as a sum of quasistationary states decay rates. This method naturally takes into account the atomic structure of the tip and crystal surfaces as well as their mutual influence. In the weak tip-to-crystal coupling limit our expression for the tunneling current reduces to that derived in the Bardeen-Tersoff-Hamann method. Tunneling current relief, I-V characteristics and tunneling density of states for the Si(100)2 x 1 surface have been calculated and compared with experimental results.