A study of the Cr and Fe deep acceptors in InP by the nuclear transmutation back doping technique

Abstract

This paper reports the use of the nuclear transmutation back doping technique for studying the deep Cr and Fe acceptors in InP. The authors have demonstrated the changes in the electrical characteristics and the photoconductivity spectra for the InP materials studied brought about by this shallow donor compensation technique. In InP:Cr, it has been shown that the E vb+0.95 eV level belongs to the Cr 2- lower charge state. In InP:Fe, it has been possible to confirm some of the optical transitions involving both Fe 3- and Fe 2-. In particular, this work has confirmed that the deep level E cb-0.66 eV is the ground state of Fe 2-. This investigation has also allowed the authors to estimate the Fe doping concentration in a heavily doped sample and this has been found to be approximately 4.8*10 16 cm -3.