Ohmic Contacts to N -Type Gallium Nitride Based Semiconductors

In this work, the development and characterization of electrical and materials performance of ohmic contacts are presented. Surface treatment techniques were developed to improve the electrical characteristics of ohmic contacts. Ti/Al/Mo/Au metallization scheme was developed to form ohmic contacts to n-GaN, n-AlxGa1-xN, and AlGaN/GaN HEMTs. Materials microstructural analysis techniques were used to understand the evolution of electrical behavior of these contacts at higher temperatures.