Origin of point defects in AgInS2/GaAs epilayer obtained from photoluminescence measurement

Abstract

The AgInS2 epilayers with a chalcopyrite structure grown using a hot-wall epitaxy method have been confirmed to be a high quality crystal. From the optical absorption measurement, the temperature dependence of the energy band gap on AgInS2/GaAs was found to be Eg(T)=2.1365 eV−(9.89×10−3 eV)T2/(2930+T). After the as-grown AgInS2/GaAs was annealed in AgInS2/GaAs has been investigated by using the photoluminescence (PL) at 10 K. The native defects of VAg, VS, Agint, and Sint obtained from PL measurements were classified as a donors or acceptors type AgInS2/GaAs to an optical p type. Also, we confirmed that In in AgInS2/GaAs did not form the native defects because In in AgInS2 did exist in the form of stable bonds.