Enhanced electrical properties of flexible AlGaN/GaN HEMT arrays via stress engineering

Abstract

Wide-bandgap semiconductors, by virtue of their superior electrical and mechanical properties, enable significant performance enhancements in flexible electronics. Here, we report flexible AlGaN/GaN high-electron-mobility transistor (HEMT) arrays fabricated through deep silicon etching and wafer-scale substrate transfer processes. The flexible AlGaN/GaN HEMT devices demonstrate a maximum saturated drain current density of 166.5 mA/mm at VGS = 1 V and a peak transconductance of 42.6 mS/mm at VDS = 5 V, along with notable tolerance to mechanical deformation. Moreover, under in-plane tensile strain, the devices exhibit improved electrical performance. This enhancement is attributed to the modulation of the two-dimensional electron gas density at the AlGaN/GaN heterointerface driven by strain-induced piezoelectric polarization. These favorable characteristics underscore the strong potential of HEMTs for next-generation flexible electronic applications, particularly in fields such as biosensing, smart wearable technology, human–machine interactions, and intelligent microsystems.