Premium
Effect of thermal conductivity of substrate on laser‐induced phase transition of MoTe 2
Author(s) -
Chen Zhirong,
Nan Haiyan,
Liu Zheng,
Wang Xiaoya,
Gu Xiaofeng,
Xiao Shaoqing
Publication year - 2019
Publication title -
journal of raman spectroscopy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.748
H-Index - 110
eISSN - 1097-4555
pISSN - 0377-0486
DOI - 10.1002/jrs.5559
Subject(s) - phase transition , materials science , thermal conductivity , laser , raman spectroscopy , substrate (aquarium) , laser power scaling , phase (matter) , optoelectronics , heterojunction , chemical vapor deposition , analytical chemistry (journal) , optics , chemistry , condensed matter physics , composite material , organic chemistry , oceanography , physics , geology
The phase transition of molybdenum ditelluride (MoTe 2 ) has aroused great interest for enormous potential application in two‐dimensional (2D) optoelectronic sensors and nonvolatile information storage. Many in situ synthesis such as chemical vapor deposition and tellurization of Mo as well as postgrowth methods including thermal and strain engineering have been reported to realize the 2H‐to‐1T′ phase transition in MoTe 2 . Laser irradiation as one of thermal engineering has been demonstrated to be efficient and convenient for phase transition in MoTe 2 flakes, but the substrate effect especially the thermal conductivity of substrate has not been studied. In this work, we systematically investigate the effect of four substrates (SiO 2 , Si, PDMS, and GaAs) with different thermal conductivities on the laser‐induced phase transition of MoTe 2 . The evolutions of Raman spectra clearly reveal the phase transition from 2H to 1T′ phase in MoTe 2 on four different substrates with the increase in laser power. The laser power required for the phase transition is proportional to the substrate thermal conductivity. The PDMS substrate with the lowest thermal conductivity of 0.35 W/MK requires the lowest laser power of 2 mW to complete the phase transition. We have also fabricated a micro pattern heterostructure through artificial manipulation of the laser beam. Our work may provide valuable insights on the laser‐induced phase transition in MoTe 2 and be helpful for phase transition of other TMDs.