Effects of Proton Radiation-Induced Defects on Optoelectronic Properties of MoS2

• Published in: IEEE transactions on nuclear science Vol. 66; no. 1; pp. 413 - 419
• Main Authors: Foran, Brendan, Mann, Colin, Peterson, Mark, Bushmaker, Adam, Bo Wang, Jihan Chen, Sisi Yang, Cronin, Stephen B.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.01.2019; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Annealing; Exposure; Flakes (defects); Microscopy; Molybdenum; Molybdenum disulfide; Multilayers; Optoelectronics; Photoluminescence; Photons; Proton irradiation; Proton radiation; Protons; Radiation; Radiation effects; semiconductor nanostructures; Spectroscopy; Substrates; Sulfur; transition metal dichalcalgenide
• ISSN: 0018-9499; 1558-1578
• DOI: 10.1109/TNS.2018.2886180

We report on photoluminescence (PL) spectroscopy and transmission electron microscope imaging of suspended and substrate-supported flakes of the 2-D semiconductor MoS 2 before and after exposure to 100-keV proton radiation with fluences of 6 × 10 13 , 6 × 10 14 , and 6 × 10 15 p/cm 2 , respectively, and subsequent annealing. An indirect-to-direct bandgap transition is observed, which is preserved after annealing. This transition is accompanied by an unexpected increase in PL intensity after radiation exposure of multilayer samples, which is attributed to higher radiative efficiency of the direct-gap transition.