(A) new vacuum field transistor with insulated gate structure

Abstract

In contrast to the conventional solid state devices such as MOS or BJT which operate by the electron and hole transport in semiconductors, Vacuum Field Transistor proposed here is a device of a new concept that electrons emitted from the source by the applied gate-to-source electric field move through the vacuum channel and enter into the drain. It features a MOS-like structure with the insulated gate which is dissimilar to other vacuum transistors. Theoretical estimation was first performed with Maxwell simulator and C program. Then the devices were designed and fabricated using MOS compatible Si process. For more electron emission diamond-like carbon film was coated onto the source and lift-off process was adopted for its patterning. Electrical characteristics show that the proposed device does operate as we wanted, but the trend is so weak. Though there should be more effort to strengthen the competitiveness over the other devices, the very core seems to be the good choice of source material, which needs careful thought over field emission capability and processability, and its stability and reproducibility.