Non-invasive digital etching of van der Waals semiconductors

Jian Zhou; Chunchen Zhang; Li Shi; Xiaoqing Chen; Tae Soo Kim; Minseung Gyeon; Jian Chen; Jinlan Wang; Linwei Yu; Xinran Wang; Kibum Kang; Emanuele Orgiu; Paolo Samorì; Kenji Watanabe; Takashi Taniguchi; Kazuhito Tsukagoshi; Peng Wang; Yi Shi; Songlin Li

doi:10.1038/s41467-022-29447-6

Non-invasive digital etching of van der Waals semiconductors

Nat Commun. 2022 Apr 5;13(1):1844. doi: 10.1038/s41467-022-29447-6.

Authors

Jian Zhou^#^{1

2}, Chunchen Zhang^#^{1

3}, Li Shi⁴, Xiaoqing Chen^{1

2}, Tae Soo Kim⁵, Minseung Gyeon⁵, Jian Chen^{1

2}, Jinlan Wang⁴, Linwei Yu^{1

2}, Xinran Wang^{1

2}, Kibum Kang⁵, Emanuele Orgiu⁶, Paolo Samorì⁷, Kenji Watanabe⁸, Takashi Taniguchi⁸, Kazuhito Tsukagoshi⁸, Peng Wang^{9

10

11}, Yi Shi^{12

13}, Songlin Li^{14

15}

Affiliations

¹ National Laboratory of Solid-State Microstructures and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China.
² School of Electronic Science and Engineering, Nanjing University, Nanjing, China.
³ College of Engineering and Applied Sciences and Jiangsu Key Laboratory of Artificial Functional Materials, Nanjing University, Nanjing, China.
⁴ Department of Physics, Southeast University, Nanjing, China.
⁵ Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea.
⁶ Institut national de la recherche scientifique, Centre Énergie Matériaux Télécommunications, 1650 Blvd. Lionel-Boulet, J3X 1S2, Varennes, QC, Canada.
⁷ University of Strasbourg, CNRS, ISIS UMR 7006, 8 allée Gaspard Monge, F-67000, Strasbourg, France. samori@unistra.fr.
⁸ WPI-MANA, National Institute for Materials Science, Tsukuba, 305-0044, Ibaraki, Japan.
⁹ National Laboratory of Solid-State Microstructures and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China. wangpeng@nju.edu.cn.
¹⁰ College of Engineering and Applied Sciences and Jiangsu Key Laboratory of Artificial Functional Materials, Nanjing University, Nanjing, China. wangpeng@nju.edu.cn.
¹¹ Department of Physics, University of Warwick, CV4 7AL, Coventry, UK. wangpeng@nju.edu.cn.
¹² National Laboratory of Solid-State Microstructures and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China. yshi@nju.edu.cn.
¹³ School of Electronic Science and Engineering, Nanjing University, Nanjing, China. yshi@nju.edu.cn.
¹⁴ National Laboratory of Solid-State Microstructures and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China. sli@nju.edu.cn.
¹⁵ School of Electronic Science and Engineering, Nanjing University, Nanjing, China. sli@nju.edu.cn.

^# Contributed equally.

Abstract

The capability to finely tailor material thickness with simultaneous atomic precision and non-invasivity would be useful for constructing quantum platforms and post-Moore microelectronics. However, it remains challenging to attain synchronized controls over tailoring selectivity and precision. Here we report a protocol that allows for non-invasive and atomically digital etching of van der Waals transition-metal dichalcogenides through selective alloying via low-temperature thermal diffusion and subsequent wet etching. The mechanism of selective alloying between sacrifice metal atoms and defective or pristine dichalcogenides is analyzed with high-resolution scanning transmission electron microscopy. Also, the non-invasive nature and atomic level precision of our etching technique are corroborated by consistent spectral, crystallographic, and electrical characterization measurements. The low-temperature charge mobility of as-etched MoS₂ reaches up to 1200 cm² V^-1s^-1, comparable to that of exfoliated pristine counterparts. The entire protocol represents a highly precise and non-invasive tailoring route for material manipulation.