Date of Graduation


Document Type


Degree Type



Statler College of Engineering and Mineral Resources


Lane Department of Computer Science and Electrical Engineering

Committee Chair

Larry Hornak.


Gallium nitride, a III-V compound semiconductor, is a good candidate for applications such as blue laser diodes and power devices due to its wide bandgap. One of the main challenges related to this compound is the growth of high quality crystals. If crystals with high level of purity are grown, the carrier concentration is therefore low, and the resulting high resistivity of the bulk imposes some difficulties for capacitance-related measurements. This thesis deals with the problem of processing and characterization of contacts on highly resistive materials such as unintentionally doped n-type gallium nitride. The ideal electrical model of a depletion layer is analyzed, and modifications are proposed in order to set up a framework for measurements on low carrier concentration materials. A silicon wafer was processed to emulate the behavior of unintentionally doped gallium nitride and validate the developed characterization techniques. Measurements obtained from two samples of gallium nitride are included to illustrate how these studied methodologies can be used to obtain semiconductor parameters such as carrier concentration and built-in voltage.