Controlled Gas Molecules Doping of Monolayer MoS2 via Atomic-Layer-Deposited Al2O3 Films

Yuanzheng Li; Xinshu Li; Heyu Chen; Jia Shi; Qiuyu Shang; Shuai Zhang; Xiaohui Qiu; Zheng Liu; Qing Zhang; Haiyang Xu; Weizhen Liu; Xinfeng Liu; Yichun Liu

doi:10.1021/acsami.7b08893

Controlled Gas Molecules Doping of Monolayer MoS₂ via Atomic-Layer-Deposited Al₂O₃ Films

ACS Appl Mater Interfaces. 2017 Aug 23;9(33):27402-27408. doi: 10.1021/acsami.7b08893. Epub 2017 Aug 15.

Authors

Yuanzheng Li^{1

2

3}, Xinshu Li^{1

3}, Heyu Chen^{1

3}, Jia Shi², Qiuyu Shang⁴, Shuai Zhang², Xiaohui Qiu², Zheng Liu⁵, Qing Zhang⁴, Haiyang Xu^{1

3}, Weizhen Liu^{1

3}, Xinfeng Liu², Yichun Liu^{1

3}

Affiliations

¹ Centre for Advanced Optoelectronic Functional Materials Research and Key Laboratory of UV-Emitting Materials and Technology (Northeast Normal University), Ministry of Education , Changchun 130024, China.
² Division of Nanophotonics, CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology , Beijing 100190, China.
³ National Demonstration Center for Experimental Physics Education, Northeast Normal University , Changchun 130024, China.
⁴ Department of Materials Science and Engineering, College of Engineering, Peking University , Beijing 100871, China.
⁵ Center for Programmable Materials, School of Materials Science and Engineering, Nanyang Technological University , Singapore 639798, Singapore.

PMID: 28796477
DOI: 10.1021/acsami.7b08893

Abstract

MoS₂ as atomically thin semiconductor is highly sensitive to ambient atmosphere (e.g., oxygen, moisture, etc.) in optical and electrical properties. Here we report a controlled gas molecules doping of monolayer MoS₂ via atomic-layer-deposited Al₂O₃ films. The deposited Al₂O₃ films, in the shape of nanospheres, can effectively control the contact areas between ambient atmosphere and MoS₂ that allows precise modulation of gas molecules doping. By analyzing photoluminescence (PL) emission spectra of MoS₂ with different thickness of Al₂O₃, the doped carrier concentration is estimated at ∼2.7 × 10¹³ cm^-2 based on the mass action model. Moreover, time-dependent PL measurements indicate an incremental stability of single layer MoS₂ as the thicknesses of Al₂O₃ capping layer increase. Effective control of gas molecules doping in monolayer MoS₂ provides us a valuable insight into the applications of MoS₂ based optical and electrical devices.

Keywords: Al2O3; aomic layer deposition (ALD); gas molecules doping; monolayer MoS2; stability.