DFT Atomic-Scale Modeling and Simulation of Ultrawide Bandgap (UWBG) Heterostructured Materials

Ultra-wide bandgap (UWBG) materials (i.e., Eg &gt; 3.4 eV) possess superior material properties for enabling the next-generation of high-power density and high-performance radio-frequency (RF) monolithic microwave integrated circuit (MMIC) devices. There has been recent major interest in developing high-performance diamond electronics, but there are still some challenges which exist for diamond as a material, such as incomplete ionization for highly n+ doped epilayer films and weak electron mobility at high operating temperatures.<br/> <br/>Here, we report on a deep dive exploration into various UWBG materials (e.g., Diamond, Ga2O3, AlN, cubic boron nitride, hexagonal boron nitride, etc.), and understanding how these UWBG materials form intriguing heterogeneous interfaces with each other. High-throughput density functional theory (DFT) atomic-scale modeling and simulation studies will be presented on these various UWBG materials and a combination of UWBG heterointerfaces. Simulated electronic material parameters such as electronic band-structures, projected density of states (PDOS), electron/hole mobility, thermal conductivity, and Raman will be presented. For example, cubic boron nitride (c-BN) is strongly lattice matched to diamond, is isoelectronic with diamond, and is a strong candidate for enabling diamond/c-BN based two-dimensional electron- and hole gas (i.e., 2DEG and 2DHG) based field effect transistors and other interesting high-power device configurations. This presentation will highlight and also take a deeper exploration into various undoped and doped diamond/c-BN heterointerfaces. <br/> <br/>Overall, the presented DFT modeling and simulation results will shed light into what combination of UWBG materials are within the physical design space and will lay a general pathway for physically realizing high-power density and high-performance RF MMIC devices.