"Wide bandgap semiconductors such as GaN and AlxGa1-xN can be utilized for blue to UV light emitting diodes, lasers, and detecting devices, as well as high-frequency, high-temperature, and high-power electronic devices. However, successful fabrication of such devices must still overcome some important problems such as efficient doping and selective area doping. Thermal diffusion doping in the group-III nitrides is impractical due to the extremely low diffusivity of the impurity species. An alternative doping method other than in-situ doping of GaN materials is ion implantation. This doping technique has many advantages including independent control of the doping level, selective area doping, and the ability to fabricate planar devices and self aligned structures. However, one of the major problems associated with this technique is the need to anneal out the damage created during implantation to make the implanted ions electrically active. A doping technique of ion implantation was investigated to produce good n-type conductive GaN and AlxGa1-xN layer for application to the next generation electronic devices such as high frequency, high temperature, and high power electronic devices, and optoelectronic devices workable at short wavelengths in the UV-blue range. Both electrical and optical activation studies of Si-implanted GaN and AlxGa1-xN have been made as a function of ion does, anneal time, and anneal temperature to obtain maximum possible activation efficiency for use in advanced electronic and optoelectronic devices. The electrical activation efficiency and Hall mobility increase with anneal time and anneal temperature. The photoluminescence measurements show an excellent implantation damage recovery after annealing at the optimum anneal conditions, showing a strong near band emission, and these optical results correlate well with the electrical results. "