Accession Number:

AD1111934

Title:

Laser-Processing of VO2 Thin Films Synthesized by Polymer-Assisted-Deposition

Descriptive Note:

Journal Article - Open Access

Corporate Author:

Naval Research Laboratory Washington United States

Report Date:

2016-12-01

Pagination or Media Count:

19.0

Abstract:

We investigate a novel route for synthesis and laser-sintering of VO2 thin films via solution-based polymer-assisted-deposition PAD. By replacing the traditional solvent for PAD water with propylene glycol, we are able to control the viscosity and improve the environmental stability of the precursor. The solution stability and ability to control the viscosity makes for an ideal solution to pattern simple or complex shapes via direct-write methods. We demonstrate the potential of our precursor for printing applications by combining PAD with laser induced forward transfer LIFT. We also demonstrate large-area film synthesis on 4 in. diameter glass wafers. By varying the annealing temperature, we identify the optimal synthesis conditions, obtaining optical transmittance changes of 60 at a 2500 nm wavelength and a two-order-of-magnitude semiconductor-to-metal transition. We go on to demonstrate two routes for improved semiconductor-to-metal characteristics. The first method uses a multi-coating process to produce denser films with large particles. The second method uses a pulsed-UV-laser sintering step in films annealed at low temperatures 450 degrees C to promote particle growth and improve the semiconductor-to-metal transition. By comparing the hysteresis width and semiconductor-to-metal transition magnitude in these samples, we demonstrate that both methods yield high quality VO2 with a three-order-of-magnitude transition.

Subject Categories:

  • Coatings, Colorants and Finishes
  • Manufacturing and Industrial Engineering and Control of Production Systems
  • Electrical and Electronic Equipment
  • Solid State Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE