Optical Characterization of Heavily Sn-Doped GaAs_(1-x)Sb_x Epilayers Grown by Molecular Beam Epitaxy on (001) GaAs Substrates

摘要

We have optically investigated ternary GaAs_(1-x)Sb_x (x < 0.58) epilayers and Sn-doped GaAs_(1-x)Sb_x (x = 0.10-0.14) epilayers grown by molecular beam epitaxy on GaAs (001) substrates. Sn-doped GaAsSb layers were grown as a function of Sn Knudsen-cell temperature, and then characterized by low-temperature photoluminescence (PL) measurements and Hall effect measurements. The Sn-doped GaAsSb films grown at a K-cell temperature of 670℃ changed from exhibiting p-type conduction to exhibiting n-type conduction, and showed a maximum PL intensity and a maximum electron mobility of 1900 cm~2/Vs. The PL intensities obtained for Sn-doped GaAsSb films showed a relatively good correlation with the variations in Hall mobility.