A Low-Cost, Nanowatt, Millimeter-Scale Memristive-Vacuum Sensor

This work demonstrates a low-power, light-weight, and cost-efficient vacuum pressure sensor and air leak detector based on 2 mm
$\times2$
mm Cu/HfO
₂
/
$\text{p}^{+}$
-Si memristor device. The operating principle of the proposed sensor relies on monitoring the off-state resistance (
$\text{R}_{off}$
) of the device, wherein the experimental results show that the
$\text{R}_{off}$
value is inversely proportional to the vacuum pressure. The fabricated sensors demonstrated a sensitivity of 493 Torr
⁻¹
and power consumption as low as
$\sim 8$
nW, when tested in a wide range of sub-atmospheric pressure (
$4.9\times 10^{-5} - 760$
) Torr, making them highly suitable for low-power applications. Furthermore, it is shown that the sensor can be integrated with a microcontroller-based circuitry to serve as a standalone sensing system.