Activation energy in metal-containing DLC films with various metals of various concentrations

作者：Takeno Takanori; Hoshi Yuhtaro; Miki Hiroyuki; Takagi Toshiyuki^*

来源：Diamond and Related Materials, 2008, 17(7-10): 1669-1673.

DOI：10.1016/j.diamond.2008.03.039

• activation energy
• DLC
• metal

The activation energy of (Co, Mo, W)-containing diamond-like carbon (DLC) films with different metal concentrations was investigated. The films were deposited onto silicon substrates by radio frequency discharged methane plasma and a co-sputtering of the metal target. The structure of the films was analyzed by Raman spectroscopy and using a transmission electron microscope. The results indicated that crystalline metal clusters are dispersed in amorphous carbon insulating matrix, and hence the metal-containing DLC films investigated can be classified as granular films. The temperature dependence of the resistance was also measured. From the temperature dependence, the activation energy was calculated numerically using (sigma=sigma(0)exp(-E/kT). The calculated activation energy rapidly decreases as the metal concentration increases. This is because of the increase in the average size of the metal clusters. A detailed discussion is presented in terms of the radius of the metal clusters inside the films.

• 出版日期2008-10