Effect of Fe inter‐diffusion on properties of InP layers grown with addition of RE elements

Abstract

This contribution reports the redistribution behaviour of Fe during the growth of InP layers from liquid phase with addition of some rare earth elements on semi‐insulating InP:Fe substrates. We have studied the influence of different rare earths on the Fe diffusion into InP layer and compared it with the phenomenon of an extraction of iron from Fe doped materials into adjacent layers doped by Zn, Cd and Be, reported recently. In the case of Tm addition a conversion of electrical conductivity of InP layer to semi‐insulating as a consequence of Fe diffusion has been observed while no significant Fe inter‐diffusion has been confirmed in the presence of other investigated rare earth additions. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Annealed semi-insulating p-type InP grown by the Czochralski technique with Cu in the melt

“…Copper doped p-type SI InP can be recommended for radiation detection at room temperature because Schottky-like highly blocking electrodes could possibly be made on it. The Cu inter-diffusion between this material and p-type InP to compare it with Fe inter-diffusion [2] is to be tested.…”

“…The high diffusivity of Fe in InP degrades the thermal stability of semi-insulating InP [1]. This problem is most evident in the case of inter-diffusion with p-type InP [2]. Besides, while room-temperature detectors of radioactive radiation based on semi-insulating InP are very interesting devices, when made of Fe-doped InP their charge-collection efficiency and energy resolution are limited due to the large carrier capture cross section of Fe [3].…”

Role of Rare-Earth Elements in the Technology of III-V Semiconductors Prepared by Liquid Phase Epitaxy

“…The proposed mechanism involves an acceptor insterstitial out diffusion from the ptype material into the SI substrate. The vacancy equilibrium is shifted in p-type layer leading to the excess of the phosphorus vacancy concentration, and thus, enables a higher incorporation ratio of the substitutional Fe (Procházková et al, 2005b). The iron redistribution can be well suppressed by inserting a thin buffer layer of undoped InP.…”