DOPING OF THE WIDE-GAP SEMICONDUCTOR CD1-XMGXTE DURING MOLECULAR-BEAMEPITAXY

We investigated the n-type doping of the wide-gap II-VI semiconductor (CdMg)Te. The n-type doping of (CdMg)Te has previously been achieved i n only a small range of magnesium concentration. By the use of zinc io dine as dopant source material, we obtained highly doped (CdMg)Te laye rs up to a magnesium concentration of 40%. The limiting factor for the free carrier concentration at room temperature is the occurrence of a deep level, which dominates the electrical properties at room tempera ture of layers with more than 30% magnesium. Compensating defects or d efect complexes are considered, to explain the observed properties of the deep level, which do not seem to be characteristic of an isolated donor state.