Thermally Strained Band Gap Engineering of Transition-Metal Dichalcogenide Bilayers with Enhanced Light-Matter Interaction toward Excellent Photodetectors

Sheng Wen Wang, Henry Medina, Kuo Bin Hong, Chun Chia Wu, Yindong Qu, Arumugam Manikandan, Teng Yu Su, Po-Tsung Lee, Zhi Quan Huang, Zhiming Wang, Feng Chuan Chuang, Hao-Chung Kuo*, Yu Lun Chueh

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

33 Scopus citations

Abstract

Integration of strain engineering of two-dimensional (2D) materials in order to enhance device performance is still a challenge. Here, we successfully demonstrated the thermally strained band gap engineering of transition-metal dichalcogenide bilayers by different thermal expansion coefficients between 2D materials and patterned sapphire structures, where MoS2 bilayers were chosen as the demonstrated materials. In particular, a blue shift in the band gap of the MoS2 bilayers can be tunable, displaying an extraordinary capability to drive electrons toward the electrode under the smaller driven bias, and the results were confirmed by simulation. A model to explain the thermal strain in the MoS2 bilayers during the synthesis was proposed, which enables us to precisely predict the band gap-shifted behaviors on patterned sapphire structures with different angles. Furthermore, photodetectors with enhancement of 286% and 897% based on the strained MoS2 on cone- and pyramid-patterned sapphire substrates were demonstrated, respectively.

Original languageEnglish
Pages (from-to)8768-8776
Number of pages9
JournalACS Nano
Volume11
Issue number9
DOIs
StatePublished - 26 Sep 2017

Keywords

  • chemical vapor deposition
  • molybdenum disulfide
  • patterned sapphire substrate
  • photodetector
  • thermal strain
  • transition-metal dichalcogenide

Fingerprint Dive into the research topics of 'Thermally Strained Band Gap Engineering of Transition-Metal Dichalcogenide Bilayers with Enhanced Light-Matter Interaction toward Excellent Photodetectors'. Together they form a unique fingerprint.

Cite this