Trap Dynamics and Conductivity Changes in AlGaN/GaN Heterostructures Under Ultrasonic Loading

Abstract

AlGaN/GaN heterostructures are critical for high-power electronic devices but suffer from electron trapping at defects, limiting reliability. We investigate how ultrasonic vibrations affect electron transport in MOCVD-grown AlGaN/GaN heterostructures by combining temperature-dependent Hall effect and high-resolution X-ray diffraction measurements. Here we demonstrate that ultrasonic loading induces persistent acoustoconductivity and lattice parameter changes, attributed to acoustically driven rearrangement of metastable DX centers. This leads to increased carrier concentration and decreased mobility, reflecting defect state modulation by acoustic strain. These findings provide new insights into trap dynamics under dynamic deformation and suggest ultrasonic treatment as a potential approach to mitigate trapping effects, thereby enhancing the performance and reliability of GaN-based devices.