Experimental and theoretical investigation of phosphorus in-situ doping of germanium epitaxial layers

Abstract

We investigate phosphorus in-situ doping characteristics in germanium (Ge) during epitaxial growth by spreading resistance profiling analysis. In addition, we present an accurate model for the kinetics of the diffusion in the in-situ process, modeling combined growth and diffusion events. The activation energy and pre-exponential factor for phosphorus (P) diffusion are determined to be 1.91 eV and 3.75 x 10(-5) cm(2)/s. These results show that P in-situ doping diffusivity is low enough to form shallow junctions for high performance Ge devices. (C) 2013 Elsevier B.V. All rights reserved.