INTERACTION OF AU WITH RADIATION-INDUCED DEFECTS IN Ge_0.9Si_0.1 SINGLE CRYSTALS

摘要

Thermal stability of radiation-induced defects in single-crystal Ge_0.9Si_0.1 doped with Au and Sb was studied. At a hole concentration of (5-7)×10~14 cm~-3, an Au acceptor level at E_v + 0.15 eV is observed. Upon irradiation with 5-Me V electrons to doses from 10~13 to 4×10~15 cm~-2,this level persists; however, the hole concentration decreases drastically.At a dose of 4×10~15 cm~-2 ,a second Au acceptor levels appears at Ec -0.25 eV. The decrease in hole concentration upon irradiation is presumably related to the transition of Au atoms from substitutional to interstitial sites as a result of their interaction with radiation-induced defects.