晶胞级 Bi2O3 超薄膜转印制备与场效应晶体管特性研究OA

Conventional methods face challenges in simultaneously achieving large-area continuity,controlled chemical composition,and improved crystallinity in ultrathin Bi2O3 films.To address these challenges,unit-cell-scale ultrathin Bi2O3 films were fabricated on SiO2/Si substrates by combining contact transfer of a liquid-metal oxide layer with rapid thermal annealing.The chemical states,morphology,thickness,crystal structure,and field-effect characteristics of the films were investigated.After annealing at 400℃,no discernible metallic Bi signal was detected,and Bi was predominantly present in the+3 oxidation state.The annealed films were 1.30 nm thick and exhibited a polycrystalline cubic structure.The resulting back-gated field-effect transistors showed clear gate-voltage modulation,with an on/off current ratio of 6.93×103,a threshold voltage of 7.46 V,and a subthreshold swing of 1.15 V/dec.The nonlinearity and asymmetry of the output curves suggested possible contact-limited carrier transport.Consecutive forward and reverse gate-voltage sweeps produced a hysteresis window of 3.8 V,indicating that trap-related charge trapping and detrapping affected the threshold voltage and subthreshold characteristics of the devices.These results demonstrate that the proposed method can be used to fabricate ultrathin Bi2O3 channels and construct the corresponding field-effect devices.