Title: Optimized oxygen deprived low temperature sputtered WO3 thin films for crystalline structures

Journal Article · · Nanotechnology
ORCiD logo [1];  [1];  [2];  [1];  [1]
  1. Univ. of Illinois at Chicago, IL (United States)
  2. Argonne National Lab. (ANL), Lemont, IL (United States). Center for Nanoscale Materials

In this work, we report a detailed analysis on the effects of processing parameters for sputtered tungsten trioxide (WO3) thin nanoscale films on their structural, vibrational and electrical properties. The research aims to understand the fundamental aspects of WO3 sputtering at relatively low temperatures and in an oxygen deprived environment targeting applications of temperature and oxygen sensitive substrates. Structural analysis indicates that films deposited at room temperature, or substrate temperatures at or below 400 degrees C with low oxygen partial pressure are amorphous. Furthermore, crystallization of the films was observed with distinct Raman peaks when the films were annealed at 300 degrees C or above using rapid thermal annealing for 10 min. Films revealed monoclinic phases of WO3 with the presence of W-O-W stretching, bending and lattice vibrational modes in the Raman spectra. Interestingly, a change of transport behavior from insulating to semiconducting was observed for as deposited films on post annealing. Annealed films revealed stoichiometric WO3 phases with no external defects detected. The present study adopts a route to intercalate WO3 in a variety of applications from electrochromic coloration to a nanocrystalline thin film for electronic devices sensitive to higher temperatures and gas flow in the sputtering system.

Research Organization:
Argonne National Laboratory (ANL), Argonne, IL (United States)
Sponsoring Organization:
US Army Research Laboratory (ARL); USDOE Office of Science (SC), Office of Basic Energy Sciences (BES), Scientific User Facilities Division
Grant/Contract Number:
AC02-06CH11357
OSTI ID:
1607425
Journal Information:
Nanotechnology, Journal Name: Nanotechnology Journal Issue: 9 Vol. 31; ISSN 0957-4484
Publisher:
IOP PublishingCopyright Statement
Country of Publication:
United States
Language:
English

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