This work performs Si ion implantation the electrical conductive type of th
e p-GaN film from p-type to n-type. Multiple implantation method is also us
ed to form a uniform Si implanted region in the p-type GaN epitaxial layer.
Implant energies for the multiple implantation are 40, 100, and 200 KeV. T
he implant dose is 5 x 10(15) cm(-2) for each implant energy. After implant
ation, the samples are annealed in a N-2 ambient for different annealing te
mperatures and annealing times. The activation efficiency reaches as high a
s 20% when annealing the sample at 1000 degrees C. The carrier activation e
nergy is about 720 meV. The low activation energy indicates that the hoppin
g process mechanism is the dominant mechanism for the activation of the Si
implantation in p-GaN. Moreover, the rectifying I-V characteristic of the p
-n GaN diode is also examined.