Investigation of semiconducting properties in epitaxial AlN film and single crystal

Due to its wide bandgap of approximately 6.2 eV, high thermal conductivity and high breakdown field, aluminum nitride (AlN) has attracted lots of attention not only for power electronics applications but also for space semiconductors. However, high activation energy of p-type dopant in AlN suffers hole transport. In this study, we have performed ion-beam implantation of acceptor dopants into AlN epitaxial thin films and single crystals In order to achieve ohmic contact with metal electrodes, we investigated to find the optimal conditions for multilayer electrodes with high work function. Rapid Thermal Annealing (RTA) was employed to activate the dopants and to improve the contact resistance between the metal electrodes and p-type AlN. In this presentation, we will show the semiconductor properties of AlN epitaxial thin films and single crystals depending on implantation conditions, metallic multilayer structures, and rapid thermal annealing parameters.