Ma Qian, Zheng He-Mei, Shao Yan, Zhu Bao, Liu Wen-Jun, Ding Shi-Jin, Zhang David Wei
State Key Laboratory of ASIC and System, Shanghai Institute of Intelligent Electronics and Systems, School of Microelectronics, Fudan University, Shanghai, 200433, China.
Nanoscale Res Lett. 2018 Jan 9;13(1):4. doi: 10.1186/s11671-017-2414-0.
Atomic-layer-deposition (ALD) of InO nano-films has been investigated using cyclopentadienyl indium (InCp) and hydrogen peroxide (HO) as precursors. The InO films can be deposited preferentially at relatively low temperatures of 160-200 °C, exhibiting a stable growth rate of 1.4-1.5 Å/cycle. The surface roughness of the deposited film increases gradually with deposition temperature, which is attributed to the enhanced crystallization of the film at a higher deposition temperature. As the deposition temperature increases from 150 to 200 °C, the optical band gap (E) of the deposited film rises from 3.42 to 3.75 eV. In addition, with the increase of deposition temperature, the atomic ratio of In to O in the as-deposited film gradually shifts towards that in the stoichiometric InO, and the carbon content also reduces by degrees. For 200 °C deposition temperature, the deposited film exhibits an In:O ratio of 1:1.36 and no carbon incorporation. Further, high-performance InO thin-film transistors with an AlO gate dielectric were achieved by post-annealing in air at 300 °C for appropriate time, demonstrating a field-effect mobility of 7.8 cm/V⋅s, a subthreshold swing of 0.32 V/dec, and an on/off current ratio of 10. This was ascribed to passivation of oxygen vacancies in the device channel.
已使用环戊二烯基铟（InCp）和过氧化氢（HO）作为前驱体对氧化铟（InO）纳米薄膜的原子层沉积（ALD）进行了研究。InO薄膜可在160 - 200°C的相对低温下优先沉积，呈现出1.4 - 1.5 Å/循环的稳定生长速率。沉积薄膜的表面粗糙度随沉积温度逐渐增加，这归因于在较高沉积温度下薄膜结晶增强。随着沉积温度从150°C升高到200°C，沉积薄膜的光学带隙（E）从3.42 eV升至3.75 eV。此外，随着沉积温度的升高，沉积薄膜中In与O的原子比逐渐向化学计量比的InO转变，碳含量也逐渐降低。对于200°C的沉积温度，沉积薄膜的In:O比为1:1.36且无碳掺入。此外，通过在空气中300°C适当时间的后退火，制备出了具有AlO栅极电介质的高性能InO薄膜晶体管，其场效应迁移率为7.8 cm²/V⋅s，亚阈值摆幅为0.32 V/dec，开/关电流比为10⁷。这归因于器件沟道中氧空位的钝化。
