Effect of pulsed deposition of Al 2 O 3 for native oxides reduction of GaAs by atomic layer deposition technique

The reduction of native oxides on GaAs substrates is studied by predeposition cleaning as well as by short time pulsing of the metal precursor for the self-cleaning mechanism using atomic layer deposition (ALD) of trimethyl aluminum (TMA). The role of the predeposition cleaning followed by ALD application has significant effects in restraining the regrowth of native oxides. The short time pulsing of the TMA is effective for the self-cleaning mechanism to reduce the intensity of GaAs native oxides. The reduction in native oxides on GaAs surface during ALD of TMA was investigated using x-ray photoelectron spectroscopy. X-ray photoelectron studies demonstrated that the pulsed deposition of TMA in the range of 2 to 4 s is the most effective way of cleaning the GaAs native oxides. Our studies demonstrate a full proof self-cleaning process for GaAs wafers for any potential applications. (C) 2012 American Vacuum Society. [DOI: 10.1116/ 1.3662862]