XPS Studies on Al_xGa_1-xAs/GaAs Structure

A series of Al_xGa_1-xAs/GaAs heterojunction materials with different x value have been studied by X-ray photoelectron spectroscopy （XPS） and argon ion soputtering profile.After a definite time of ion sputtering,XPS analyses were carried out to investigate chemical states and relative contents of Al,Ga and As.It was observed that aluminum was segregated on surface and arsenic was preferentially sputtered.The Al content was quantitatively determined by XPS and then the x value can be deduced.As compared with that measured by photoluminescence （PL） method ,a good linear relationship between these two x value can be estimated.