Integration of GaAs/In0.1Ga0.9As/AlAs resonance tunneling heterostructures into micro‐electro‐mechanical systems for sensor applications

Double‐barrier quantum‐well resonant tunneling heterostructures of GaAs/In 0.1 Ga 0.9 As/AlAs have been used as pressure‐sensing elements of designed micro‐electro‐mechanical systems. The static experiments have been conducted on the heterostructure, in both positive and negative differential resistance (PDR and NDR) regions, showing a piezoresistive coefficient of 3.85 × 10 −9 Pa −1 , which is about seven times larger than that of piezoresistive silicon devices. At the same time, the devices also provided an improved dynamic response (119.6 µV · g −1 V −1 ) and signal‐to‐noise ratio (57 dB) in the NDR region.