UNIVERSAL IRON BEHAVIOR IN ZN-DOPED, CD-DOPED AND BE-DOPED PARA-TYPE INP

We studied iron redistribution behaviour during MOVPE growth using Zn-, Cd- and Be-doped layers fabricated by MOVPE, LPE and CBE methods respectively. Common phenomena of a fast extraction of iron from semi-insulating material into p-doped material. independent of the acceptor, have been observed in InP layers. In contrast, an iron diffusion has not been observed in undoped or n-doped material. In order to explain the observed behaviour, we propose that the simple interstitial-substitutional diffusion mechanism is modified in acceptor doped layers. Possible mechanisms of iron-acceptor exchange or/and acceptor interstitial leakage are discussed. This work may have a direct impact on the applicability of semi-insulating layers in the electronic and optoelectronic device design.