Selective plasma oxidation of GaAs—a study of the interface properties

Studies by electron and photon spectroscopy show that plasma grown GaAs oxide possesses an excess amount elemental As at the oxide—GaAs interface. This amount has been found to be inversely proportional to the growth rate. The excess elemental As is deleterious to the electrical properties of MOS devices. A selective plasma oxidation process using fluorinated oxygen gas shows that the excess As at the interface can be greatly reduced. The resultant electrical properties are also improved.