Enormous enhancement in electrical performance of few-layered MoTe2 due to Schottky barrier reduction induced by ultraviolet ozone treatment  

作　　者：Xiaoming Zheng Xueao Zhang Yuehua Wei Jinxin Liu Hang Yang Xiangzhe Zhang Shitan Wang Haipeng Xie Chuyun Deng Yongli Gao Han Huang 

机构地区：[1]Hunan Key Laboratory of Super-microstructure and Ultrafast Process,School of Physics and Electronics,Central South University,Changsha 410083,China [2]College of Arts and Science,National University of Defense Technology,Changsha 410073,China [3]College of Physical Science and Technology,Xiamen University,Xiamen 361005,China [4]Department of Physics and Astronomy,University of Rochester,Rochester,NY 14627,USA

出　　处：《Nano Research》2020年第4期952-958,共7页纳米研究（英文版）

基　　金：We acknowledge the financial support from the National Natural Science Foundation of China(Nos.11874427,11874423).Dr.H an H uang acknowledges support from the Innovation-Driven project of Central South University(No.2017CX018)and from the Natural Science Foundation of H unan province(No.2016JJ1021).Mr.Xiaoming Zheng acknowledges the support from the Fundamental Research Funds for the Central Universities of Central South University(No.2017zzts066).

摘　　要：Doping can improve the band alignment at the metal-semiconductor interface to modify the corresponding Schottky barrier,which is crucial for the realization of high-performance logic components.Here,we systematically investigated a convenient and effective method,ultraviolet ozone treatment,for p-type doping of MoTe2 field-effect transistors to enormously enhance the corresponding electrical performance.The resulted hole concentration and mobility are near 100 times enhanced to be〜1.0×10^13 cm^-2 and 101.4 cm^2/(V·s),respectively,and the conductivity is improved by 5 orders of magnitude.These values are comparable to the highest ones ever obtained via annealing doping or non-lithographic fabrication methods at room temperature.Compared with the pristine one,the photoresponsivity(522 mA/W)is enhanced approximately 100 times.Such excellent performances can be attributed to the sharply reduced Schottky barrier because of the surface charge transfer from MoTe2 to MoOx(x<3),as proved by photoemission spectroscopy.Additionally,the p-doped devices exhibit excellent stability in ambient air.Our findings show significant potential in future nanoelectronic and optoelectronic applications.

关 键 词：MoTe2 ultraviolet ozone surface charge transfer Schottky barrier air stable hole doping 

分 类 号：TN23[电子电信—物理电子学]