Stoichiometric, epitaxial ZrB2 thin films with low oxygen-content deposited by magnetron sputtering from a compound target: Effects of deposition temperature and sputtering power
2015 (English)In: Journal of Crystal Growth, ISSN 0022-0248, E-ISSN 1873-5002, Vol. 430, 55-62 p.Article in journal (Refereed) Published
Zirconium diboride (ZrB2) thin films have been deposited on 4H-SiC(0001) substrates by direct current magnetron sputtering from a compound target. The effect of deposition temperature (500-900 degrees C) and sputtering power (100-400 W) on the composition and structure of the films have been investigated. Electron microscopy and X-ray diffraction reveal that high sputtering power values and high deposition temperatures are favorable to enhance the crystalline order of the epitaxial 0001 oriented films. X-ray photoelectron spectroscopy shows that the composition of the films is near-stoichiometric for all deposition temperatures and for high sputtering power values of 300 W and 400 W, whereas under-stoichiometric films arc obtained when applying 100 W or 200 W. Decreasing the deposition temperature, or in particular the sputtering power, result in higher C and O impurity levels. The resistivity of the films was evaluated by four-point-probe measurements and found to scale with the amount of O impurities in the films. The lowest resistivity value obtained is 130 mu Omega cm, which makes the ZrB2 films interesting as an electrical contact material. (C) 2015 Elsevier B.V. All rights reserved.
Place, publisher, year, edition, pages
ELSEVIER SCIENCE BV , 2015. Vol. 430, 55-62 p.
X-ray diffraction; X-ray photoelectron spectroscopy; Physical vapor deposition processes; Borides
Physical Sciences Chemical Sciences
IdentifiersURN: urn:nbn:se:liu:diva-122186DOI: 10.1016/j.jcrysgro.2015.08.012ISI: 000362014800010OAI: oai:DiVA.org:liu-122186DiVA: diva2:865067
Funding Agencies|Swedish Research Council (VR) [621 2010-3921]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant) [SFO-Mat-LiU 2009-00971]; VINN Excellence Center Functional Nanoscale Materials (FunMat) [2005-02666]; Knut and Alice Wallenberg Foundation [2011.0143]2015-10-262015-10-232016-08-31