Orientation-engineered halide perovskite single-crystal cathodes for efficient field emission in nano vacuum channel transistors

Abstract Nano vacuum channel transistors (NVCTs) are increasingly recognized as a promising class of devices for high-frequency, radiation-hardened, and beyond-complementary metal-oxide-semiconductor (CMOS) electronics, yet their progress has been constrained by the low emission current, high turn-on voltage, and limited manufacturability. Here, we reported the first integration of halide perovskite single crystals (MAPbBr3, MA stands for methylammonium) as the electron emitter in NVCTs, achieving performance levels incomparable to those using other cathode materials. Remarkably, even with a large vacuum channel length of ~ 230 nm, the devices delivered drain currents up to 1.26 mA and operated at a remarkably low turn-on voltage of 8 V in air, highlighting their exceptional emission capability. The perovskite-assisted NVCTs exhibited a robust gate modulation with negligible leakage and pronounced photo-responsivity, enabling potential electrical–optical joint control. Importantly, the devices were fabricated on display glass substrates using thin-film transistor-liquid crystal display (TFT-LCD) manufacturing processes, offering a pathway toward low-cost, scalable, and integrable nano-vacuum electronics. This work established perovskite single crystals as a new material platform for manufacturable, multifunctional vacuum electronics with relevance to the next-generation information and communication technologies.