ACS Appl Mater Interfaces. 2018 Jun 27;10(25):21061-21065. doi: 10.1021/acsami.8b05229. Epub 2018 Jun 18.
The high room-temperature mobility that can be achieved in BaSnO has created significant excitement for its use as channel material in all-perovskite-based transistor devices such as ferroelectric field effect transistor (FET). Here, we report on the first demonstration of n-type depletion-mode FET using hybrid molecular beam epitaxy grown La-doped BaSnO as a channel material. The devices utilize a heterostructure metal-oxide semiconductor FET (MOSFET) design that includes an epitaxial SrTiO barrier layer capped with a thin layer of HfO used as a gate dielectric. A field-effect mobility of ∼70 cm V s, a record high transconductance value of >2mS/mm at room temperature, and the on/off ratio exceeding 10 at 77 K were obtained. Using temperature- and frequency-dependent transport measurements, we quantify the impact of the conduction band offset at the BaSnO/SrTiO interface as well as bulk and interface traps on device characteristics.
在 BaSnO 中实现的高温室迁移率为其在全钙钛矿基晶体管器件（如铁电场效应晶体管（FET））中作为沟道材料的应用创造了巨大的兴奋。在这里，我们报告了使用混合分子束外延生长的 La 掺杂 BaSnO 作为沟道材料的首例 n 型耗尽模式 FET 的首次演示。这些器件采用异质结构金属氧化物半导体 FET（MOSFET）设计，包括外延 SrTiO 势垒层，其顶部覆盖有一层用作栅介质的薄 HfO。在室温下获得了约 70cm V s 的场效应迁移率、>2mS/mm 的超高跨导值以及超过 77K 的 10 以上的导通/关断比。通过温度和频率相关的输运测量，我们量化了 BaSnO/SrTiO 界面处导带偏移以及体和界面陷阱对器件特性的影响。
