Surfactant effects on GaAs–Ge heterostructures

Publication date: 1 October 2013
Source:Journal of Crystal Growth, Volume 380
Author(s): L.B. Karlina , A.S. Vlasov , B.Y. Ber , D.Yu. Kazanthev , E.P. Marukhina
A study of the effect of isoelectronic surfactants (In and P) on the photoluminescence and photovoltaic characteristics of GaAs–Ge heterostructures is presented. The surfactants were introduced into the structure by simultaneous post-growth diffusion. A GaAs photoluminescence spectra analysis was performed via a layer-by-layer etching procedure. It is shown that the effect of the surfactants is observed over a wide concentration range from 3×10¹⁷ to 1×10²⁰ cm⁻³. The effects of the In and P passivation of nonradiative recombination centers are observed. A p–n junction was formed via phosphorus diffusion. PV conversion efficiency of 3.2% for the 900–1840nm wavelength region has been registered under 40–400x concentrated sunlight (AM1.5D low-AOD).