Nanoelectromechanical Resonators Enabled by Si-Doped Semiconducting β-Ga2O3 Nanobelts

We report on demonstration of ultrawide bandgap $\beta-\mathbf{Ga}_{2}\mathbf{O}_{3}$ nanoelectromechanical resonators vibrating in the high and very high frequency (HF & VHF) bands. The resonators are fabricated by synthesis of Si-doped $\beta-\mathbf{Ga}_{2}\mathbf{O}_{3}$ nanostructures using low-pressure chemical vapor deposition (LPCVD), followed by dry transfer of the nanomaterials onto prefabricated substrate with microtrenches. Using an ultrasensitive laser interferometry system, we observe multimode thermomechanical resonances in the HF & VHF bands from these $\beta-\mathbf{Ga}_{2}\mathbf{O}_{3}$ resonators. Further, additional anchoring and contacting electrodes are explored by using stencil-mask patterning and metallization, for enhancing the clamping and electrical contact of $\beta-\mathbf{Ga}_{2}\mathbf{O}_{3}$ crystal.