Characteristics of Doping and Diffusion of Heavily Doped N and P type InP and InGaAs Epitaxial Layers grown by Metal Organic Chemical Vapor Deposition

Electronic and photonic device applications of the InGaAs/InP materials system often require the growth of epitaxial material doped to or near the solubility limit of the impurity in the host material. These requirements present an extreme challenge for the crystal grower. To produce devices with abrupt dopant profiles, preserve the junction during subsequent growth, and retain a high degree of crystalline perfection, it is necessary to understand the limits of dopant incorporation and the behavior of the impurity in the material.In this study, N-type doping above 1019 cm-3 has been achieved in InP and InGaAs using Sn as a dopant P-type Zn doping at these levels has also been achieved in these materials but p type activation above ~3 × 1018 cm-3 in InP has not been seen. All materials were grown by the metalorganic chemical vapor deposition (MOCVD) crystal growth technique. Effective diffusion coefficients have been measured for Zn and Sn in both materials from analysis of secondary ion mass spectra (SIMS) of specially grown and annealed samples.