A synoptic review of nanoscale vacuum channel transistor: Fabrication to electrical performance

The vacuum channel transistor has emerged as a promising candidate for next-generation technology due to its intriguing features compared to the conventional field effect transistor. Nanoscale vacuum channel transistors have a particular advantage due to the promise of vacuum-like ballistic transport, radiation insensitivity, and nanoscale dimensions. Unlike field emission devices, nanoscale vacuum channel transistors can induce electron emission at a desired temperature; sharp and thin emitters on the cathode are desired to increase field emission. This article provides a comprehensive overview of recent research advancements. It begins with a brief introduction to vacuum transistors and their miniaturization to the nanoscale. Then, recent advancements in different architectures with vacuum gaps, including their physical properties, fabrication methods, and device applications, are discussed. Finally, this review concludes by highlighting some challenges and perspectives in this emerging field.