Electrical Properties of the Si Implantation in Mg Doped p-GaN

This work performs Si ion implantation to activate and convert the electrical conduction of p-GaN films from p-type to n-type. Multiple implantation method is used to form a uniform Si implanted region in the p-type GaN epitaxial layer. Implantation energies for the multiple implantation are 40, 100, and 200 keV. The implantation dose is 5 × 1015 cm2 for each implantation energy. After implantation, the samples were annealed in an N2 ambient for different annealing temperatures and annealing times. The activation efficiency reaches as high as 20% when annealing the sample at 1000 °C. The carrier activation energy is about 720 meV. The low activation energy indicates that the hopping process mechanism is the dominant mechanism for the activation of the Si implant in p-GaN. In addition, the rectifying I–V characteristic of the p–n GaN diode is also examined.