ChemInform Abstract: Molecular Beam Epitaxy Grown Al(Ga)InAs: Schottky Contacts and Deep Levels.

Abstract

Molecular Beam Epitaxy Grown Al(Ga)InAs: Schottky Contacts and Deep Levels.-It is shown that the crystalline quality of MBE grown Al(Ga)InAs layers on InP substrates is lowest for AlInAs and is significantly improved by low Ga concentrations. Reliable Schottky contacts with high barriers up to 0.73 eV and low leakage current densities of 0.22 . mu.A/mm2 are obtained by treating the surface with buffered phosphoric acid before metal evaporation. The deep level concentration of AlxGayIn1-x-yAs is found to decrease with increasing Ga content (by a factor of 2 from y = 0 to y = 0.12). The reduced trap concentration of the quaternary material is explained by the improved layer quality. -(SCHRAMM, C.; BACH, H. G.; KUENZEL, H.; PRASEUTH, J. P.; J. Electrochem. Soc. 138 (1991) 9, 2808-2811; Heinrich-Hertz-Inst. Nachrichtentech. Berlin