Nanoscale Vacuum Channel Hall Sensors

Nanoscale vacuum channel Hall sensors (NVCHSs) were fabricated and simulated. The fabrication flow was compatible with the complementary metal–oxide–semiconductor (CMOS) process, and the active area was etched by using focused ion beam (FIB) technology. The current–voltage (<inline-formula> <tex-math notation="LaTeX">${I}$ </tex-math></inline-formula>–<inline-formula> <tex-math notation="LaTeX">${V}$ </tex-math></inline-formula>) characteristics of the bias terminals were measured to analyze the electron emission mechanism. Hall measurements were performed at ambient conditions to evaluate the Hall voltage, linearity, and voltage-related sensitivity of the proposed Hall sensor. The linearity error was less than 5%, and the voltage-related sensitivity was 0.28 V/VT. The performance of the sensor was similar to that of the common micrometer-sized Hall sensor, but with the benefits of small size and easy integration. Ultimately, a finite-element method (FEM) simulation was performed to show the potential distribution during normal sensor operation and to demonstrate the possibility of high-frequency operation. This work clearly outlines the potential of nanoscale vacuum channel technology in Hall sensor applications.