INTERFACE FORMATION BETWEEN DEPOSITED SN AND HG0.8CD0.2TE

The structure of the interface formed by the reaction of deposited Sn on Hg0.78Cd0.22Te(111)B was investigated by hemispherically scanned x- ray photoelectron spectroscopy including x-ray photoelectron diffracti on (XPD). The interface formation was found to proceed as follows: At the onset of Sn deposition, Hg is expelled and substituted by Sn in th e topmost monolayer of the Hg0.78Gd0.22Te lattice while the zinc-blend e structure of the original surface is maintained. With further Sn dep osition (and further loss of Hg), an epitaxial layer of cubic SnTe (wi th inclusions of CdTe) was found to grow. At room temperature, the SnT e growth stopped after a few monolayers, and the epitaxial growth of c ubic alpha-Sn was observed to start on top of it. At elevated depositi on temperatures, the SnTe intermediate layer continued to grow up to s everal 100 Angstrom.