Li Shasha, Zhang Xinan, Zhang Penglin, Song Guoxiang, Yuan Li
College of Engineering Physics, Shenzhen Technology University, Shenzhen 518118, China.
School of Physics and Electronics, Henan University, Kaifeng 475004, China.
Nanomaterials (Basel). 2022 Aug 14;12(16):2783. doi: 10.3390/nano12162783.
The use of the semiconductor heterojunction channel layer has been explored as a method for improving the performance of metal oxide thin-film transistors (TFTs). The excellent electrical performance and stability of heterojunction TFTs is easy for vacuum-based techniques, but difficult for the solution process. Here, we fabricated InO/InO:Gd (InO/InGdO) heterojunction TFTs using a solution process and compared the electrical properties with single-layer InO TFTs and InO:Gd (InGdO) TFTs. The InO/InGdO TFT consisted of a highly conductive InO film as the primary transmission layer and a subconductive InGdO film as the buffer layer, and exhibited excellent electrical performance. Furthermore, by altering the Gd dopant concentration, we obtained an optimal InO/InGdO TFT with a higher saturation mobility (µ) of 4.34 cmVs, a near-zero threshold voltage (V), a small off-state current (I) of 1.24×10-9 A, a large on/off current ratio (I/I) of 3.18×105, a small subthreshold swing (SS), and an appropriate positive bias stability (PBS). Finally, an aging test was performed after three months, indicating that InO/InGdO TFTs enable long-term air stability while retaining a high-mobility optimal switching property. This study suggests that the role of a high-performance InO/InGdO heterojunction channel layer fabricated by the solution process in the TFT is underlined, which further explores a broad pathway for the development of high-performance, low-cost, and large-area oxide electronics.
人们已经探索了使用半导体异质结沟道层来提高金属氧化物薄膜晶体管（TFT）性能的方法。异质结TFT优异的电学性能和稳定性对于基于真空的技术来说比较容易实现，但对于溶液法来说却很困难。在此，我们采用溶液法制备了InO/InO:Gd（InO/InGdO）异质结TFT，并将其电学性能与单层InO TFT和InO:Gd（InGdO）TFT进行了比较。InO/InGdO TFT由高导电性的InO薄膜作为主要传输层和亚导电性的InGdO薄膜作为缓冲层组成，并表现出优异的电学性能。此外，通过改变Gd掺杂浓度，我们获得了一种优化的InO/InGdO TFT，其具有4.34 cm²V⁻¹s⁻¹的更高饱和迁移率（µ）、接近零的阈值电压（V）、1.24×10⁻⁹ A的小关态电流（I）、3.18×10⁵的大开/关电流比（Ion/Ioff）、小的亚阈值摆幅（SS）以及适当的正偏压稳定性（PBS）。最后，在三个月后进行了老化测试，结果表明InO/InGdO TFT能够实现长期的空气稳定性，同时保持高迁移率的最佳开关性能。这项研究强调了通过溶液法制备的高性能InO/InGdO异质结沟道层在TFT中的作用，这进一步探索了高性能、低成本和大面积氧化物电子学发展的广阔途径。
