Manufacture and applications of GaN-based piezotronic and piezo-phototronic devices

Abstract

Driven by the urgent demands for information technology, energy, and intelligent industry， third-generation semiconductor GaN has emerged as a pivotal component in electronic and optoelectronic devices. Piezoelectric polarization is the most essential feature of GaN materials. GaN materials based on piezotronics/phototronics combine mechanical signals with electrical signals/optical signals to achieve multi-field coupling of device performance. Piezotronics regulates the carrier transport process in micro-nano devices, which has been proven to significantly improve the performance of devices (such as HEMTs and MicroLEDs) and brings many novel applications. This review examines GaN material properties and the theoretical foundations of piezotronics and phototronics. It also explores GaN device fabrication and integration processes to achieve state-of-the-art device performance. This review also analyzes the impact of introducing three-dimensional stress and regulatory forces on devices' electrical and optical output performance. Additionally, it discusses new applications of GaN devices in neural sensing, optoelectronic output, and energy harvesting. Finally, the potential of piezotronic-controlled GaN devices offers insights for future research and the development of multi-functional, diversified electronic devices.