Figures

Figure 1

SRPES spectra: (a) Ga 3d photoelectrons, (b) O 1s photoelectrons and (c) valence bands with surface treatments. The position of valence band maximum was determined by the linear extrapolation as shown in (c).

Figure 2

Change of Ga/N atomic ratio with the detection angle. The surface normal of sample was defined as 90°.

Figure 3

Schematic of energy band diagrams below the interfaces of Ti/n-type GaN: (a) the HCl-treated contact and (b) the plasma-treated contact.

© 2001 The Materials Research Society