Electrical and optical properties of sputtered amorphous vanadium oxide thin films

N. J. Podraza, B. D. Gauntt, M. A. Motyka, E. C. Dickey, Mark William Horn

Research output: Contribution to journalArticle

18 Scopus citations

Abstract

Amorphous vanadium oxide (VO x) is a component found in composite nanocrystalline VO x thin films. These types of composite films are used as thermistors in pulsed biased uncooled infrared imaging devices when containing face centered cubic vanadium monoxide phase crystallites, and substantial fractions of amorphous material in the composite are necessary to optimize device electrical properties. Similarly, optoelectronic devices exploiting the metal-to-semiconductor transition contain the room-temperature monoclinic or high-temperature (68 C) rutile vanadium dioxide phase. Thin films of VO x exhibiting the metal-to-semiconductor transition are typically polycrystalline or nanocrystalline, implying that significant amounts of disordered, amorphous material is present at grain boundaries or surrounding the crystallites and can impact the overall optical or electronic properties of the film. The performance of thin film material for either application depends on both the nature of the crystalline and amorphous components, and in this work we seek to isolate and study amorphous VO x. VO x thin films were deposited by pulsed dc reactive magnetron sputtering to produce amorphous materials with oxygen contents 2, which were characterized electrically by temperature dependent current-voltage measurements and optically characterized by spectroscopic ellipsometry. Film resistivity, thermal activation energy, and complex dielectric function spectra from 0.75 to 6.0 eV were used to identify the impact of microstructural variations including composition and density.

Original languageEnglish (US)
Article number073522
JournalJournal of Applied Physics
Volume111
Issue number7
DOIs
StatePublished - Apr 1 2012

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Electrical and optical properties of sputtered amorphous vanadium oxide thin films'. Together they form a unique fingerprint.

  • Cite this