Spontaneous delamination via compressive buckling facilitates large‐scale β‐Ga2O3 thin film transfer from reusable GaAs substrates

Abstract

The fabrication and transfer via spontaneous delamination of large‐area, high‐quality β‐Ga2O3 nanoscale thin films with centimeter‐scale dimensions is demonstrated via thermal oxidation of reusable GaAs substrates. The films are characterized by using X‐ray diffraction, energy dispersive spectroscopy, Raman spectroscopy, and scanning electron microscopy. The film demonstrates good mechanical flexibility facilitating reliable transfer. The β‐Ga2O3 film's optical band gap and Schottky barrier height with gold are 4.8 and 1.03 eV, respectively. Electrical and optical properties of the transferable β‐Ga2O3 thin films exhibit a potential for application in solar‐blind photodetectors. The scale of the β‐Ga2O3 films transferred herein exceeds what the research community has reported to‐date by more than four orders of magnitude. The macroscopic dimensions of the transferred films may offer a remedy for the low thermal conductance of β‐Ga2O3 via transfer onto substrates with high thermal conductivity.