Silicon and Selenium Doping Effects on Band-Gap Energy and Sublattice Ordering in Ga_0.5In_0.5P Grown by Metalorganic Vapor Phase Epitaxy

Abstract

Effects of n -type dopants Si and Se on band-gap energy ( E g ) and on sublattice ordering for Ga 0.5 In 0.5 P grown by metalorganic vapor phase epitaxy, under conditions in which E g shows anomalously low E g values if the doping is not carried out, were studied by means of photoluminescence and transmission electron microscopy. In contrast to the previously reported p -type doping case, the effects on E g were interpreted by considering two factors: (i) impurity-doping-induced diorsdering of <1/2, 1/2, 1/2 > superlattice (SL), and (ii) Burstein shift.