Chen Wan-Hsin, Kawakami Naoya, Hsueh Jing-Wen, Kuo Lai-Hsiang, Chen Jiun-Yu, Liao Ting-Wei, Kuo Chia-Nung, Lue Chin-Shan, Lai Yu-Ling, Hsu Yao-Jane, Lien Der-Hsien, Hu Chenming, Chou Jyh-Pin, Luo Meng-Fan, Lin Chun-Liang
Department of Electrophysics, National Yang Ming Chiao Tung University, Hsinchu 300, Taiwan.
Department of Physics, National Central University, Jhongli 320, Taiwan.
ACS Appl Mater Interfaces. 2023 Mar 29;15(12):16153-16161. doi: 10.1021/acsami.2c21150. Epub 2023 Feb 21.
Layered transition metal dichalcogenides (TMDs) are two-dimensional materials exhibiting a variety of unique features with great potential for electronic and optoelectronic applications. The performance of devices fabricated with mono or few-layer TMD materials, nevertheless, is significantly affected by surface defects in the TMD materials. Recent efforts have been focused on delicate control of growth conditions to reduce the defect density, whereas the preparation of a defect-free surface remains challenging. Here, we show a counterintuitive approach to decrease surface defects on layered TMDs: a two-step process including Ar ion bombardment and subsequent annealing. With this approach, the defects, mainly Te vacancies, on the as-cleaved PtTe and PdTe surfaces were decreased by more than 99%, giving a defect density <1.0 × 10 cm, which cannot be achieved solely with annealing. We also attempt to propose a mechanism behind the processes.
层状过渡金属二硫属化物（TMDs）是二维材料，具有多种独特特性，在电子和光电子应用方面具有巨大潜力。然而，用单层或几层TMD材料制造的器件性能会受到TMD材料表面缺陷的显著影响。最近的努力集中在精确控制生长条件以降低缺陷密度，而制备无缺陷表面仍然具有挑战性。在这里，我们展示了一种降低层状TMDs表面缺陷的反直觉方法：包括氩离子轰击和随后退火的两步过程。通过这种方法，在刚解理的PtTe和PdTe表面上的缺陷（主要是碲空位）减少了99%以上，缺陷密度<1.0×10 cm，这是仅通过退火无法实现的。我们还试图提出这些过程背后的机制。
