Electric field-induced redistribution of free carriers at isotype (In,Ga)P/GaAs interfaces

• Published in: Materials science & engineering. B, Solid-state materials for advanced technology Solid-state materials for advanced technology, 2002-01, Vol.88 (2), p.129-133
• Main Authors: Krispin, P, Knauer, A, Gramlich, S
• Format: Article
• Language: English
• Subjects: (In,Ga)P ordering; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic transport in interface structures; Exact sciences and technology; InGaP/GaAs interfaces; Other semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions; Physics; Sheet charges
• ISSN: 0921-5107; 1873-4944
• DOI: 10.1016/S0921-5107(01)00866-2

Metal–semiconductor contacts are applied to study depth-resolved electrical characteristics of Si- and Zn-doped GaAs/(In,Ga)P/GaAs heterojunctions by capacitance–voltage measurements. The measured depth profiles of the carrier concentration are compared with calculations based on solutions of the Poisson equation. Different growth conditions are chosen in order to produce heterointerfaces with (In,Ga)P layers of various degrees of order. It is shown that (In,Ga)P ordering induces piezoelectric polarization charges at interfaces with GaAs, the density of which increases with higher degree of order. The related electric field results in a redistribution of free carriers. For weakly ordered (In,Ga)P, the interfaces are found to be of type I.