TY - JOUR
T1 - Chemical trends of deep levels in van der Waals semiconductors
AU - Ci, Penghong
AU - Tian, Xuezeng
AU - Kang, Jun
AU - Salazar, Anthony
AU - Eriguchi, Kazutaka
AU - Warkander, Sorren
AU - Tang, Kechao
AU - Liu, Jiaman
AU - Chen, Yabin
AU - Tongay, Sefaattin
AU - Walukiewicz, Wladek
AU - Miao, Jianwei
AU - Dubon, Oscar
AU - Wu, Junqiao
N1 - Funding Information:
This work was supported by the Electronic Materials Program funded by the Director, Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The device fabrication was partly supported by the Center for Energy Efficient Electronics Science (NSF Award No. 0939514). J.M. and X.T. acknowledge the support by the US Department of Energy, Office of Science, Basic Energy Sciences, Division of Materials Sciences and Engineering under award DE-SC0010378 and by an Army Research Office MURI grant on Ab-Initio Solid-State Quantum Materials: Design, Production and Characterization at the Atomic Scale (18057522). We are grateful for Prof. Mary Scott and Dr. Yaqian Zhang for assistance in TEM, and Dr. Muhua Sun for drawing the schematic of the DLTS device.
Publisher Copyright:
© 2020, The Author(s).
PY - 2020/12/1
Y1 - 2020/12/1
N2 - Properties of semiconductors are largely defined by crystal imperfections including native defects. Van der Waals (vdW) semiconductors, a newly emerged class of materials, are no exception: defects exist even in the purest materials and strongly affect their electrical, optical, magnetic, catalytic and sensing properties. However, unlike conventional semiconductors where energy levels of defects are well documented, they are experimentally unknown in even the best studied vdW semiconductors, impeding the understanding and utilization of these materials. Here, we directly evaluate deep levels and their chemical trends in the bandgap of MoS2, WS2 and their alloys by transient spectroscopic study. One of the deep levels is found to follow the conduction band minimum of each host, attributed to the native sulfur vacancy. A switchable, DX center - like deep level has also been identified, whose energy lines up instead on a fixed level across different hosts, explaining a persistent photoconductivity above 400 K.
AB - Properties of semiconductors are largely defined by crystal imperfections including native defects. Van der Waals (vdW) semiconductors, a newly emerged class of materials, are no exception: defects exist even in the purest materials and strongly affect their electrical, optical, magnetic, catalytic and sensing properties. However, unlike conventional semiconductors where energy levels of defects are well documented, they are experimentally unknown in even the best studied vdW semiconductors, impeding the understanding and utilization of these materials. Here, we directly evaluate deep levels and their chemical trends in the bandgap of MoS2, WS2 and their alloys by transient spectroscopic study. One of the deep levels is found to follow the conduction band minimum of each host, attributed to the native sulfur vacancy. A switchable, DX center - like deep level has also been identified, whose energy lines up instead on a fixed level across different hosts, explaining a persistent photoconductivity above 400 K.
UR - http://www.scopus.com/inward/record.url?scp=85093914922&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85093914922&partnerID=8YFLogxK
U2 - 10.1038/s41467-020-19247-1
DO - 10.1038/s41467-020-19247-1
M3 - Article
C2 - 33097722
AN - SCOPUS:85093914922
SN - 2041-1723
VL - 11
JO - Nature Communications
JF - Nature Communications
IS - 1
M1 - 5373
ER -