Beta-gallium oxide is an ultra wide band gap semiconductor material that holds promise for the next generation of power electronic devices. Its wide bandgap allows for the material to sustain a large electric field before critical failure. Taking advantage of this intrinsic property allows for smaller power electronic devices with a lower on resistance. In addition, gallium oxide can be melt grown, making it a cost-effective material. Despite gallium oxide's many advantages over existing semiconductor materials, it is still in the early stages of development and lacks demonstration of ~100% device yield on large area wafers. In order to improve this yield, this investigation examines the uniformity of gallium oxide films grown on 2 inch melt grown gallium oxide substrates. To determine uniformity we use three different electrical characterization techniques to find and confirm the key parameters. First we take Transfer Length Measurements(TLMs) to find the sheet resistance and contact resistance. Then, we take Capacitance-Voltage measurements to examine the charge profile and electron concentration of our films. Lastly, we take Hall measurements to examine sheet charge and mobility. Current preliminary data shows a contact resistance of 7 ±3 Ω.mm and a sheet resistance of 1.2 ±0.2 kΩ/sq. Finding the other electrical characteristics of the large area films will aid in the progression toward industrial production. Ultimately, gallium oxide shows great promise to create high-efficiency power electronic devices, which are critical in the improvements of electric transportation and a reduction in the burning of fossil fuels.
David Lopez
Project Year
Faculty Sponsor(s):
Sriram Krishnamoorthy
Mentor(s):
Carl Peterson