III-nitride MQW-based optoelectronic sensors for multifunctional environmental monitoring

This work presents an integrated multi-quantum well (MQW) optoelectronic sensor leveraging III-nitride materials for multifunctionality on a monolithic chip. The sensor was fabricated using standard microfabrication techniques and adopted the identical InGaN/GaN MQWs, which enables simultaneous emission and detection. The sensor is featured with a double concentric circle structure which supports both on-chip and off-chip detection mechanisms, being capable of detecting environmental parameters like rotational speed, proximity, and sucrose concentration. It exhibits stable photocurrent response to rotational speed up to 8000 rpm, a 3 cm vertical detection range, and a linear response with 3.9 nA/% sensitivity to changes in sucrose concentration, which demonstrates the potential for diverse applications in industrial and biomedical fields.