The effect of argon plasma cleaning on the surface characteristics of GaAs substrate

In this paper, GaAs substrate samples were treated by different Ar ion plasma cleaning process, and then a SiO2 passivation layer was deposited by radio frequency magnetron sputtering to avoid reoxidation or recontamination of the surface. Morphology, composition and fluorescence properties of GaAs substrate surface were investigated respectively by scanning electron microscope, energy dispersive X-ray spectrometer and rapid photoluminescence mapper. The results showed that GaAs samples treated under the condition of sputtering power 8W, chamber pressure 4.7Pa, Ar flow rate 40sccm and cleaning time 48min are free from damage, the oxygen and carbon content on the sample surface decreased obviously. Photoluminescence (PL) intensity increased by 66.73 %.