TEMPERATURE PROGRAMMED DESORPTION STUDY OF (NH4)2SX TREATED GAAS-SURFACES

The effect of the (NH4)2Sx treatment temperature on the sulfide layer formed on GaAs(001) surface is investigated by RHEED and temperature programmed desorption (TPD). Decrease of the oxide layer formed during the chemical etching process is clarified by RHEED. The TPD result also indicates that the (NH4)2Sx treatment decreases the oxide layer. However, a small fraction of the surface oxide still remains on the treated GaAs surface. The desorbing species detected as sulfide is Ga2S. Change in the treatment temperature does not affect the desorption of Ga2O. An increase of the treatment temperature caused an increase of the activation energy of Ga2S desorption.