Improvement of AlSiO/GaN interface by a novel post deposition annealing using ultra high pressure

Abstract A novel post-deposition annealing technique employing ultra-high pressure was demonstrated. A 40 nm thick AlSiO gate insulator was deposited using ALD on n-type GaN layers. These PDAs were performed at 600 ºC in N2 under 400 MPa, with normal pressure. The annealing duration was varied within the range of 10-120 min. For the normal pressure annealing, the flat-band voltage exhibited a shift towards the positive bias direction as the annealing duration increased. Conversely, for the 400 MPa, the flat-band voltage approached the ideal curve. These results suggest that this annealing technique could be a method for improving the interfacial characteristics.