1. IV. Results and Discussion Effect of Substrate Bias on Structure and Properties of W Incorporated Diamond-like Carbon Films Ai-Ying Wang 1, Kwang-Ryeol Lee 1*, 1 Future Technology Research Division, Korea Institute of Science and Technology, Seoul, South Korea I. I. Abstract W incorporated diamond-like carbon (W-DLC) films were deposited on silicon (100) wafer by a hybrid deposition method combining an ion beam deposition of carbon with a DC magnetron sputtering of W. During 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 conditions, 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 the bias voltage of -200 V, which represented the highest sp 3 bond fraction in the film. The highest residual stress, hardness and Young’s modulus were also observed at the bias voltage of -200 V. These results showed that the mechanical properties of W-DLC film were mainly dependent on the atomic bond structure of carbon. On the other hand, the electrical resistivity significantly decreased by the W incorporation. III. III. Experiment II. II. Introduction Significant progress in the understanding of DLC films growth processes has been achieved in the last three decades. Nevertheless, high residual compressive stress (up to 12GPa) and poor adhesion are still the main barrier to their widely industrial applications. Recently, it is reported that Me-DLC films have shown considerable improvement of physical properties than those of pure DLC films. Taking into account each metal owning its characteristics and significant effects of ion energy on growth behaviors of film, however, more elaborate studies on Me-DLC films are required. In this paper, we reported the deposition behavior of W- DLC films and especially the dependence of structure and properties of the film on the negative bias voltage by a comprehensive set of experiments. Schematic diagram of the used system Working gas: Ar, C 6 H 6 Base pressure : 2.0  10 -6 Torr Deposition Pressure : 0.6 ~ 1  10 -4 Torr Ion gun power: 135-200V; 0.48A Sputter gun power: 600V, 0.10~0.16A Bias Voltage : 0 ~ - 600 V Substrate : P-type Si (100) wafer Thickness: 350±60nm Total flow rate: 12sccm Deposition parameters a) RBS spectra. The W concentration is mainly dependent on the Ar fraction in supplying gas, and varied a little within  0.5 at.% as the bias voltage in the range of 0 ~ -600V. The highest stresses and mechanical properties of W-DLC films were all obtained at -200V, respectively, which supposed the structure-property relationship was essentially the same as that in pure DLC films. b) Residual compressive stress and mechanical properties. c) Micro-Raman spectra and G-peak positions. G-peak positions with unstressed state proposed the highest fraction of sp 3 carbon bond occurring at -200V, which agreed well with the results of residual stress and mechanical properties. d) Electrical resistivity. The gradual decrease of resistivity by factor of 3~5 is primarily due to the increase of sp 2 carbon bond caused by the increase of W concentration, and the changes in atomic bond structure from the diamond-like phase to the graphitic one with the increase of negative bias voltage. V. Conclusions  The W-DLC films were deposited by a novel hybrid system consisted of an ion beam deposition of carbon and a DC magnetron sputtering of tungsten.  The W-DLC films were deposited by a novel hybrid system consisted of an ion beam deposition of carbon and a DC magnetron sputtering of tungsten.  Increasing W concentration in the film, for all negative bias voltage, decreased the fraction of sp 3 hybridized carbon bond in the film.  Increasing W concentration in the film, for all negative bias voltage, decreased the fraction of sp 3 hybridized carbon bond in the film.  Despite of significant addition of W, the lowest G-peak position observed at -200V, representing the highest fraction of sp 3 carbon bond, showed that the residual stress and mechanical properties of the W-DLC films were mainly dependent on the changes in the atomic bond structure of carbon network.  Despite of significant addition of W, the lowest G-peak position observed at -200V, representing the highest fraction of sp 3 carbon bond, showed that the residual stress and mechanical properties of the W-DLC films were mainly dependent on the changes in the atomic bond structure of carbon network.  W incorporation made it possible to control the electrical resistivity while the mechanical properties were dominated by the atomic bond structure of carbon.  W incorporation made it possible to control the electrical resistivity while the mechanical properties were dominated by the atomic bond structure of carbon.