Effect of Substrate Bias on Structure and Properties of W incorporated Diamond-like Carbon Films Ai-Ying Wang and Kwang-Ryeol Lee Future Technology Research Division, Korea Institute of Science and Technology, P.O.Box 131, Cheongryang, Seoul, 130-650, South Korea ABSTRACT W incorporated diamond-like carbon (W-DLC) films were deposited on silicon (100) wafers by a hybrid deposition method combining ion beam deposition of carbon with DC magnetron sputtering of tungsten. During the films deposition, a wide range of negative bias voltage from 0 to -600 V was applied. W concentration in the film could be controlled by varying the Ar/C 6 H 6 ratio in the supplying gas. In the present experimental condition, WC 1-x nano-sized particles were not observed in the amorphous carbon matrix. Regardless of the W concentration in the film, it was found that the G-peak position of the Raman spectra had a lowest value at a bias voltage of -200 V, which represents the highest sp 3 bond fraction in the film. The highest residual stress, hardness and Young’s modulus were also observed when the bias voltage was -200 V. This result shows that the mechanical properties of W-DLC films were mainly dependent on the atomic bond structure of carbon. On the other hand, the electrical resistivity significantly decreased by the W incorporation. INTRODUCTION After Aisenberg et al. firstly reported the synthesis of diamond-like (DLC) carbon films using a low energy carbon ion beam [1], significant progress in the understanding the growth process of DLC films has been achieved in the last three decades. One noteworthy feature is that the incorporation of metallic components (Ti, W, Ag, Cu, Si, Au etc.) or other third elements (N, Ar, B) is used to overcome the shortcomings of DLC films such as high residual compressive stress, poor thermal stability and ductility [2-12]. Earlier studies on the third element addition showed a considerable improvement of the physical properties of the metal containing DLC films (Me-DLC). Recently, nanocomposite films composed of nano-sized particulates dispersed in the matrix phase drew much attention due to its potential of unique properties. Nevertheless, the size, volume fraction and distribution of the nanometer metallic particulates formed in the films must be optimized carefully [13]. In the present work, we report the deposition behavior of W incorporated DLC (W-DLC) films. It is widely accepted that the Me-DLC films consist of the embedded nanometer metallic particulates (if metal formed carbides) and amorphous carbon or hydrocarbon matrix. However, we focus on the deposition behavior of the films at low W concentration where WC 1-x particulate phase does not form. The dependence of the structure and properties of the deposited film on the negative bias voltage are studied by a comprehensive set of experiments. We confirm that the W P3.22.1 Mat. Res. Soc. Symp. Proc. Vol. 821 © 2004 Materials Research Society