STM study of the Te/Si(100) interface

The structure of Te/Si(100)-(2 x 1) has been studied by scanning tunnelling microscopy (STM). The samples were prepared as follows: first, Te was depo sited at elevated temperature, then a CdTe((111) over bar)B film was grown by molecular beam epitaxy. The structural quality of the CdTe film was chec ked by double-crystal X-ray diffraction. Finally, the CdTe film was desorbe d at 500 degrees C in ultra-high vacuum. Auger electron spectroscopy confir ms previous photoelectron spectroscopy data showing that this procedure res ults in a Te coverage of about one monolayer. In addition to the well-known (2 x 1) reconstruction of the Te/Si(100) surface, STM reveals areas of a ( 3 x 1)-like reconstruction which are probably related to defects on the Si surface. We propose a model in which the STM images from both these reconst ructions can be explained in terms of buckled or non-buckled Te dimers. (C) 1999 Elsevier Science B.V. All rights reserved.