Dual-gate MoS2 phototransistor with atomic-layer-deposited HfO2 as top-gate dielectric for ultrahigh photoresponsivity
Dual-gate MoS2 phototransistor with atomic-layer-deposited HfO2 as top-gate dielectric for ultrahigh photoresponsivity
复制标题
采用原子层沉积 HfO2 作为顶栅电介质的双栅极 MoS2 光电晶体管，具有超高光响应性
DOI：
10.1088/1361-6528/abe2cc
复制
发表时间：
2021-05-21
期刊：
影响因子：
3.5
通讯作者：
Lu, Hong-Liang
中科院分区：
文献类型：
--
作者：
Li, Xiao-Xi;Chen, Xin-Yu;Lu, Hong-Liang
采用原子层沉积的HfO 2作为顶栅介质，研制了一种具有良好电学性能和光学响应的非对称双栅MoS 2场效应晶体管（FET）。MoS 2 FET的有效DG调制表现出出色的电气性能，具有6 x 10（8）的高开/关电流比。此外，在DG MoS 2光电晶体管中，可以获得作为TG电压的函数的从-20.5到-39.3V的大的阈值电压调制。同时，在550 nm激光照射下，系统地研究了不同栅偏压和不同照射光功率下薄膜的光学特性。由于DG形成的电场可以有效地分离光生电子和空穴，因此DG-MoS_2光电晶体管的结构具有2.04 × 10 ~（5）AW ~（-1）的光电响应度。因此，具有高光响应性的二维材料的DG设计为光电器件的应用提供了一个有希望的机会。
An asymmetric dual-gate (DG) MoS2 field-effect transistor (FET) with ultrahigh electrical performance and optical responsivity using atomic-layer-deposited HfO2 as a top-gate (TG) dielectric was fabricated and investigated. The effective DG modulation of the MoS2 FET exhibited an outstanding electrical performance with a high on/off current ratio of 6 x 10(8). Furthermore, a large threshold voltage modulation could be obtained from -20.5 to -39.3 V as a function of the TG voltage in a DG MoS2 phototransistor. Meanwhile, the optical properties were systematically explored under a series of gate biases and illuminated optical power under 550 nm laser illumination. An ultrahigh photoresponsivity of 2.04 x 10(5) AW(-1) has been demonstrated with the structure of a DG MoS2 phototransistor because the electric field formed by the DG can separate photogenerated electrons and holes efficiently. Thus, the DG design for 2D materials with ultrahigh photoresponsivity provides a promising opportunity for the application of optoelectronic devices.