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تسجيل مستخدم جديدYoungs Modulus and Corresponding Orientation in beta-Ga2O3 Thin Films Resolved by Nanomechanical Resonators
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We report on the non-destructive measurement of Youngs modulus of thin-film single crystal beta gallium oxide (beta-Ga2O3) out of its nanoscale mechanical structures by measuring their fundamental mode resonance frequencies. From the measurements, we extract Youngs modulus in (100) plane, EY,(100) = 261.4+/-20.6 GPa, for beta-Ga2O3 nanoflakes synthesized by low-pressure chemical vapor deposition (LPCVD), and Youngs modulus in [010] direction, EY,[010] = 245.8+/-9.2 GPa, for beta-Ga2O3 nanobelts mechanically cleaved from bulk beta-Ga2O3 crystal grown by edge-defined film-fed growth (EFG) method. The Youngs moduli extracted directly on nanomechanical resonant device platforms are comparable to theoretical values from first-principle calculations and experimentally extracted values from bulk crystal. This study yields important quantitative nanomechanical properties of beta-Ga2O3 crystals, and helps pave the way for further engineering of beta-Ga2O3 micro/nanoelectromechanical systems (M/NEMS) and transducers.
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