Neutral defects MBE films CdHgTe

Abstract

Electro–physical and optical investigations of defect structure of CdHgTe films grown by molecular–beam epitaxy (MBE) were carried out. It was shown that the films contained neutral defects, which were formed at the stage of the growth and were specific to MBE–grown material. It is suggested that the defects in question are tellurium nanocomplexes. Under ion milling, these defects are activated by interstitial mercury and form donor centers with concentration of ~1017 cm-3, which makes it possible to detect them with the use of electrical measurements. It is shown also, that under arsenic doping of CdHgTe with high–temperature cracking, the dimers As2 in the arsenic flux block formation of neutral Te nanocomplexes with formation of As2Te3 donor complexes. The results of electro–physical investigations are compared to these of micro–Raman spectroscopy.