All-electronic Switch Exceeding 10 THz

We propose to develop a new solid-state, ultra-high frequency metal transistor that exploits the recently discovered dual nature of charge carriers in “goniopolar” materials, where the carrier polarity (electron or hole nature) changes with the crystallographic direction. Such metallic transistors can achieve ultra-high frequencies at unprecedented power levels because they avoid the large capacitive effects that limit high-frequency behavior in semiconductor-based transistors. Capacitive effects are caused by depletion layers at junctions between different materials or doped regions with charge carrier concentrations low enough to act as insulators. Current technology is unable to achieve switching or amplification without the integration of those different materials or doped regions. The proposed single-material all-metal bipolar transistor circumvents this problem and would have the potential for ultra-high frequency and high-power switching not previously thought achievable, since it is a junction-free device made from goniopolar metal with majority electron-conduction along one crystallographic axis and hole-conduction along an orthogonal axis. Efforts will focus on the material Re4Si7 and its implementation into a multistage cascade to optimize gain. Using technology computer aided design (TCAD), we will first design the optimized device structure and operation along with limits for contact resistance, before eventually testing this new device architecture.