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Title: Phase transition of Al 2 O 3 -encapsulated MoTe 2 via rapid thermal annealing
Among group VI transition metal dichalcogenides, MoTe 2 is predicted to have the smallest energy offset between semiconducting 2H and semimetallic 1T′ states. This makes it an attractive phase change material for both electronic and optoelectronic applications. Here, we report fast, nondestructive, and full phase change in Al 2 O 3 -encapsulated 2H-MoTe 2 thin films to 1T′-MoTe 2 using rapid thermal annealing at 900 °C. Phase change was confirmed using Raman spectroscopy after a short annealing duration of 10 s in both vacuum and nitrogen ambient. No thickness dependence of the transition temperatures was observed for flake thickness ranging from 1.5 to 8 nm. These results represent a major step forward in understanding the structural phase transition properties of MoTe 2 thin films using external heating and underline the importance of surface encapsulation for avoiding thin film degradation.  more » « less
Award ID(s):
1843395
PAR ID:
10341468
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Applied Physics Letters
Volume:
121
Issue:
3
ISSN:
0003-6951
Page Range / eLocation ID:
033101
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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