Robust n-type doping of WSe2 enabled by controllable proton irradiation  

作　　者：Haidong Liang Yue Zheng Leyi Loh Zehua Hu Qijie Liang Cheng Han Michel Bosman Wei Chen Andrew A.Bettiol 

机构地区：[1]Centre for Ion Beam Applications(CIBA),Department of Physics,National University of Singapore,Singapore 117542,Singapore [2]International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education,Institute of Microscale Optoelectronics,Shenzhen University,Shenzhen 518060,China [3]Department of Physics,National University of Singapore,Singapore 117551,Singapore [4]Department of Materials Science and Engineering,National University of Singapore,Singapore 117575,Singapore [5]Department of Chemistry,National University of Singapore,Singapore 117543,Singapore [6]Division of Physics and Applied Physics,School of Physical and Mathematical Science,Nanyang Technological University,Singapore 637371,Singapore [7]Songshan Lake Materials Laboratory,Songshan Lake Mat Lab,Dongguan 523808,China [8]National University of Singapore(Suzhou)Research Institute,377 Lin Quan Street,Suzhou Industrial Park,Suzhou 215123,China

出　　处：《Nano Research》2023年第1期1220-1227,共8页纳米研究（英文版）

基　　金：The authors acknowledge financial support from NRF CRP on Oxide Electronics on Silicon Beyond Moore(NRF-CRP15-2015-01);the National Natural Science Foundation of China(Nos.U2032147,21872100,and 62004128);Singapore MOE Grant T2EP50220-0001,MOE AcRF Tier 1 Startup grant R-284-000-179-133;the Science and Engineering Research Council of A*STAR(Agency for Science,Technology and Research)Singapore,under Grant No.A20G9b0135;the Fundamental Research Foundation of Shenzhen(No.JCYJ20190808152607389).

摘　　要：Two-dimensional(2D)transition metal dichalcogenides(TMDs)are considered to be promising building blocks for the next generation electronic and optoelectronic devices.Various doping schemes and work function engineering techniques have been explored to overcome the intrinsic performance limits of 2D TMDs.However,a reliable and long-time air stable doping scheme is still lacking in this field.In this work,we utilize keV ion beams of H2+to irradiate layered WSe2 crystals and obtain efficient n-type doping effect for all irradiated crystals within a fluence of 1×1014 protons·cm−2(1e14).Moreover,the irradiated WSe2 remains an n-type semiconductor even after it is exposed to ambient conditions for a year.Localized ion irradiation with a focused beam can directly pattern on the sample to make high performance homogenous p-n junction diodes.Raman and photoluminescence(PL)spectra demonstrate that the WSe2 crystal lattice stays intact after irradiation within 1e14.We attribute the reliable electrondoping to the significant increase in Se vacancies after the proton irradiation,which is confirmed by our scanning transmission electron microscope(STEM)results.Our work demonstrates a reliable and long-term air stable n-type doping scheme to realize high-performance electronic TMD devices,which is also suitable for further integration with other 2D devices.

关 键 词：WSe2 proton beam irradiation n-type doping long-time air stable Se vacancies 

分 类 号：O57[理学—粒子物理与原子核物理]