Measurement of GaAs/InP and InAs/InP heterojunction band offsets by x-ray photoemission spectroscopy

Abstract

The unstrained valence‐band offset ΔE_v for the x=0 and x=1 end points of the In_xGa_1−xAs/InP (100) heterojunction system has been measured by x‐ray photoemission spectroscopy (XPS). Although the GaAs/InP and InAs/InP interfaces are strained because of lattice mismatch, the ΔE_v values obtained by the XPS measurement method used are characteristic of an unstrained interface. Values of ΔE_v (GaAs/InP)=0.19 eV and ΔE_v (InAs/InP)=0.31 eV are observed. A linear interpolation between the x=0 and x=1 values gives ΔE_v (In_0.53 Ga_0.47As/ InP)=0.25 eV for the x=0.53 lattice‐matched interface (ΔE_c /ΔE_v =58/42).