Presentation Information
[11a-PA6-13]Local surface potential measurement of GaN thin films by Kelvin probe force microscopy
〇Haruhito Echigo1, Gen Fujitsuka1, Toshiki Okamura1, Hirofumi Yamada2, Shin-ichi Yamamoto1, Yuji Miyato1 (1.Ryukoku univ., 2.Cent. of Sci. and Tech. Ryukoku Univ.)
Keywords:
Gallium nitride,Kelvin probe force microscopy,Sputtering
We are studying sputter-deposited GaN thin films as a promising approach to low-cost light-emitting device fabrication. We fabricated GaN thin films on Si substrates by RF sputtering, followed by annealing. We evaluated their local surface potential under vacuum using frequency-modulated Kelvin probe force microscopy (FM-KFM). In one case involving Si-doped films, the surface potential of the GaN thin film was about 0.05 V higher than that of the Pt reference film. This indicates that the work function of GaN is lower than that of Pt. Furthermore, we observed variations in local potential distributions, which we attribute to defects in the films. In this presentation, we will report results for different process conditions, including dopant species and annealing temperatures, and discuss their effects.