Lu Jianting, Zhang Lingjiao, Ma Churong, Huang Wenjing, Ye Qiaojue, Yi Huaxin, Zheng Zhaoqiang, Yang Guowei, Liu Chuan, Yao Jiandong
State Key Laboratory of Optoelectronic Materials and Technologies, Nanotechnology Research Center, School of Materials Science & Engineering, Sun Yat-sen University, Guangzhou, 510275, Guangdong, P. R. China.
State Key Laboratory of Optoelectronic Materials and Technologies and Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou, 510275, China.
Nanoscale. 2022 Apr 21;14(16):6228-6238. doi: 10.1039/d1nr08134a.
Over the past decade, 2D elemental semiconductors have emerged as an ever-increasingly important group in the 2D material family due to their simple crystal structures and compositions, and versatile physical properties. Taking advantage of the relatively small bandgap, outstanding carrier mobility, high air-stability and strong interactions with light, 2D tellurium (Te) has emerged as a compelling candidate for use in ultra-broadband photoelectric technologies. In this study, high-quality centimeter-scale Te nanofilms have been successfully produced by exploiting pulsed-laser deposition (PLD). By performing deposition on pre-patterned SiO/Si substrates, a Te/Si 2D/3D heterojunction array is formed . To our delight, taking advantage of the relatively small bandgap of Te, the Te/Si photodetectors demonstrate an ultra-broadband photoresponse from ultraviolet to near-infrared (370.6 nm to 2240 nm), enabling them to serve as important alternatives to conventional 2D materials such as MoS. In addition, an outstanding on/off ratio of ∼10 and a fast response rate (a response/recovery time of 3.7 ms/4.4 ms) are achieved, which is associated with the large band offset and strong interfacial built-in electric field that contribute to suppressing the dark current and separating photocarriers. Beyond these, a 35 × 35 matrix array has been successfully constructed, where the devices exhibit comparable properties, with a production yield of 100% for 100 randomly tested devices. The average responsivity, external quantum efficiency and detectivity reach 249 A W, 76 350% and 1.15 × 10 Jones, respectively, making the Te/Si devices among the best-performing 2D/3D heterojunction photodetectors. On the whole, this study has established that PLD is a promising technique for producing high-quality Te nanofilms with good scalability, and the Te/Si 2D/3D heterojunction provides a promising platform for implementing high-performance ultra-broadband photoelectronic technologies.
在过去十年中，二维元素半导体因其简单的晶体结构和组成以及多样的物理性质，在二维材料家族中已成为越来越重要的一类。利用相对较小的带隙、出色的载流子迁移率、高空气稳定性以及与光的强相互作用，二维碲（Te）已成为用于超宽带光电技术的极具吸引力的候选材料。在本研究中，通过利用脉冲激光沉积（PLD）成功制备出了高质量的厘米级碲纳米薄膜。通过在预先图案化的SiO/Si衬底上进行沉积，形成了Te/Si二维/三维异质结阵列。令我们高兴的是，利用碲相对较小的带隙，Te/Si光电探测器展现出从紫外到近红外（370.6纳米至2240纳米）的超宽带光响应，使其能够成为诸如MoS等传统二维材料的重要替代品。此外，实现了约10的出色开/关比和快速响应速率（响应/恢复时间为3.7毫秒/4.4毫秒），这与大的带偏移和强大的界面内建电场有关，有助于抑制暗电流并分离光载流子。除此之外，成功构建了一个35×35的矩阵阵列，其中器件表现出可比的性能，100个随机测试器件的成品率为100%。平均响应度、外量子效率和探测率分别达到249 A/W、76350%和1.15×10 Jones，使Te/Si器件成为性能最佳的二维/三维异质结光电探测器之一。总体而言，本研究证实了PLD是一种用于制备具有良好可扩展性的高质量碲纳米薄膜的有前景的技术，并且Te/Si二维/三维异质结为实现高性能超宽带光电子技术提供了一个有前景的平台。
