Department of Physics, University of Texas-Arlington , Arlington, Texas 76019, United States.
Department of Physics and Astronomy, University of Nebraska-Lincoln , Lincoln, Nebraska 68588, United States.
Nano Lett. 2017 Oct 11;17(10):6248-6257. doi: 10.1021/acs.nanolett.7b02947. Epub 2017 Sep 13.
The epitaxial growth of multifunctional oxides on semiconductors has opened a pathway to introduce new functionalities to semiconductor device technologies. In particular, the integration of gate materials that enable nonvolatile or hysteretic functionality in field-effect transistors could lead to device technologies that consume less power or allow for novel modalities in computing. Here we present electrical characterization of ultrathin single crystalline SrZrTiO (x = 0.7) films epitaxially grown on a high mobility semiconductor, Ge. Epitaxial films of SrZrTiO exhibit relaxor behavior, characterized by a hysteretic polarization that can modulate the surface potential of Ge. We find that gate layers as thin as 5 nm corresponding to an equivalent-oxide thickness of just 1.0 nm exhibit a ∼2 V hysteretic window in the capacitance-voltage characteristics. The development of hysteretic metal-oxide-semiconductor capacitors with nanoscale gate thicknesses opens new vistas for nanoelectronic devices.
在半导体上外延生长多功能氧化物为半导体器件技术引入新功能开辟了一条途径。特别是，在场效应晶体管中集成能够实现非易失性或滞后功能的栅极材料，可以导致功耗更低的器件技术，或者允许在计算中采用新的模式。在这里，我们展示了在高迁移率半导体 Ge 上外延生长的超薄单晶 SrZrTiO（x = 0.7）薄膜的电特性。SrZrTiO 的外延薄膜表现出弛豫行为，其特征是滞后极化，可以调制 Ge 的表面势。我们发现，厚度薄至 5nm 的栅极层（对应于仅 1.0nm 的等效氧化物厚度）在电容-电压特性中表现出约 2V 的滞后窗口。具有纳米级栅极厚度的滞后金属氧化物半导体电容器的发展为纳米电子器件开辟了新的前景。
