Effect of radio frequency power on the inductively coupled plasma etched Al0.65Ga0.35N surface

The etching effects on the surface and electrical characteristics of high Al mole fraction AlxGa1−xN (x = 0.65) have been characterized by X-ray photoelectron spectroscopy (XPS) and transfer length method (TLM) as a function of radio frequency power. XPS results show that the Ga–N and Al–N peaks move to the lower energy after ICP etchings. An increase in the amount of oxygen and a decrease in the amount of nitrogen are observed for the etched samples along with the RF power. The annealing at 450 °C is partly effective on removing the oxygen amount which would come from the C–O component and recovering the N deficiencies on the surface of etched sample. The extracted sheet resistance of the AlGaN layer from TLM increases gradually after ICP etching with an increase of RF power. The correlation between the XPS peaks and the electrical properties of the etched samples has been discussed and the annealing effect on the inverse leakage current of the p-i-n AlGaN solar blind UV detector is examined.