Amorphous BaTiO₃ (a ‐BTO) thin films are deposited on p ‐Si(111) substrates by radio frequency (RF) magnetron sputtering without extra substrate heating. The microstructure of a ‐BTO thin films is modified by postannealing at low temperatures (260–600 °C) in air. The results show that distorted TiO₆ octahedra exist in a ‐BTO thin films, and the degree of distortion decreases when the annealing temperature rises. The concentration of O vacancies in the TiO₆ of the thin films remains high when postannealed between 370 and 460 °C, and a built‐in electric field across the a ‐BTO/p ‐Si heterojunction is established in this annealing temperature range. This built‐in electric field is regulated by controlling the concentration of O vacancies from the TiO₆. The tunable C–V characteristic of the Au/a ‐BTO/p ‐Si metal–oxide–semiconductor (MOS) capacitor is obtained by modulating the built‐in electric field at the heterojunction, and the flat band voltage of the MOS capacitor shifts from about −3 V to at least −13 V when the postannealing temperature increases from 260 to 420 °C. This kind of tunable built‐in electric field at the a ‐BTO/p ‐Si heterojunction, controlled by modifying the microstructure of amorphous oxide thin films, has never been observed before, which will be useful for MOS applications.

中文翻译：

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用于金属-氧化物-半导体应用的a-BaTiO3 / p-Si异质结中具有可调内置电场的非晶BaTiO3薄膜的TiO6八面体中氧空位的控制

通过射频（RF）磁控溅射将非晶BaTiO ₃（a- BTO）薄膜沉积在p- Si（111）衬底上，而无需额外的衬底加热。的显微组织一-BTO薄膜是通过在空气中在低温（260-600℃）后续退火修改。结果表明，二氧化钛扭曲₆在八面体存在一个-BTO薄膜，并且当退火温度的升高失真的程度降低。在使TiOø空位浓度₆ 370和460℃之间postannealed当薄膜仍然很高，和一个内置的电场横跨一个-BTO / p在此退火温度范围内建立了Si异质结。通过控制来自TiO ₆的O空位的浓度可以调节这种内置电场。Au / a- BTO / p -Si金属氧化物半导体（MOS）电容器的可调C–V特性是通过调制异质结处的内置电场获得的，并且MOS电容器的平带电压偏移当后退火温度从260°C升高到420°C时，温度从大约-3V降低到至少-13V。这种可调谐的内建电场在一个-BTO / p通过改变非晶氧化物薄膜的微观结构来控制的Si异质结从未见过，这对于MOS应用很有用。