研究的目的為探討基板偏壓對於氮化釩薄膜結構與性質之影響，試圖找到優化的鍍膜參數範圍。本實驗是利用非平衡磁控濺鍍系統將奈米晶氮化釩(VN)鍍著於(111)矽晶片上，並且在攝氏200度及300度的鍍膜溫度下，應用範圍由0至-120伏特之基板偏壓，實驗結果指出，所有試片都維持在化學劑量比之內且薄膜在攝氏300度之鍍膜溫度其(200)織構強度比在200度時更高。在本研究中，我們發現在基板偏壓小於-45伏特的情況下，雖然由X光繞射圖譜結果顯示氮化釩薄膜擁有極佳結晶度，但由掃描式電子顯微鏡(SEM)觀察薄膜剖面圖發現薄膜微結構為鬆散及多孔隙的柱狀晶，薄膜電阻率上升，機械性質不佳。當基板偏壓超過-45伏特以上，薄膜微結構由鬆散的柱狀晶轉變為緻密的柱狀晶粒，消除了大部分晶粒間或柱狀晶間的孔隙，在攝氏200度或300度，氮化釩薄膜的性質都有顯著的改善。在基板偏壓為-60伏特至-90伏特之間，氮化釩薄膜保持優異的性質，包括：高硬度、高輝度、低電阻及平坦的表面。故在-60伏特至-90伏特之基板偏壓範圍及攝氏200度和300度之鍍膜溫度區間為本研究發現之適當鍍膜窗口，使氮化釩薄膜的平均硬度能夠達到26.9 GPa、平均電阻率達到51μΩ-cm。在鍍膜過程中，鍍膜溫度能夠提供熱能給成長中之薄膜，而基板偏壓除了提供動能給薄膜原子之外，還會轉移動量使原子遷移率上升，因此鍍膜溫度及基板偏壓對薄膜產生協同效應,共同影響薄膜之微結構變化。當不施加基板偏壓時，因為溫度提供的熱能之影響，氮化釩薄膜在不同溫度時會有性質改變的現象；倘若施加基板偏壓至相當程度，溫度提供的熱能量之影響減弱，取而代之的是由基板偏壓主導氮化釩薄膜性質變化。

The objective was to investigate the influence of negative substrate bias on the structure and properties of VN films and further refined the deposition window with excellent properties based on optimum conditions of previous study.
The VN films were deposited by DC unbalanced magnetron sputtering system (UBMS) on Si (100) substrate at 200oC and 300oC. The substrate bias was chosen from 0 to -120V. The results of experiments showed that the all VN specimens maintained a stoichiometric composition regardless of the substrate bias and possessed a stronger (200) texture at the deposited temperature of 300oC rather than 200oC. In this study, when applied substrate bias was less than -45V, the VN films exhibited an excellent crystallinity from XRD patterns. However, the SEM cross-sectional images showed that the microstructure of VN films composed a loose columnar structure and porous grains which was detrimental to the mechanical properties and the electrical resistivity. When the substrate bias exceeded -45V, the microstructure of VN thin films changed from loose column to densely packed fibrous structure with subtle intergrain or intercolumnar voids, which significantly improving the properties at both temperatures such as high hardness, outstanding brilliance, low electrical resistivity, and smooth surface morphology. The refined deposition window of VN thin films was at the substrate bias of -60 to -90V where the hardness and electrical resistivity of VN thin films were respectively around 26.9 GPa and 51 μΩ-cm for the temperature ranges between 200oC and 300oC. In addition, the synergetic effect of temperature induced thermal energy and substrate bias induced momentum during deposition process controlled the evolution of the microstructure of VN films. Without applied substrate bias, the properties of VN thin films had a variation between the deposited temperature of 200oC and 300oC which was due to the effect of thermal energy. When the substrate bias reached a higher level, the effect of temperature was diminished and the substrate bias dominated the properties of VN thin films.

[1] W.D. Sproul, “Very High-Rate Reactive Sputtering of TiN, ZrN and HfN”, Thin Solid Films, 107 (1983) 141-147.
[2] S. Veprek, M.J.G. Veprek-Heijman, “Industrial applications of superhard nanocomposite coatings”, Surf. Coat. Technol., 202 (2008) 5063-5073.
[3] E. Budke, J. Krempel-Hesse, H. Maidhof, H. Schussler, “Decorative hard coatings with improved corrosion resistance”, Surf. & Coat. Technol., 112 (1999) 108-113.
[4] X. Chu, S.A. Barnett, M.S. Wong, W.D. Sproul, “Reactive magnetron sputter deposition of polycrystalline vanadium nitride films”, J. Vac. Sci. Technol., A 14 (1996) 3124-3129.
[5] M.B. Takeyama, T. Itoi, K. Satoh, M. Sakagami, A. Nyoa, “Application of thin nanocrystalline VN film as a high-performance diffusion barrier between Cu and SiO2”, J. Vac. Sci. Technol., B 22 (2004) 2542-2547.
[6] J.C. Caicedo, G. Zambrano, W. Aperador, L. Escobar-Alarcon, E. Camps, “Mechanical and electrochemical characterization of vanadium nitride (VN) thin films”, Appl. Surf. Sci., 258 (2011) 312-320.
[7] X.P. Qu, M. Zhou, T. Chen, Q. Xie, G.P. Ru, B.Z. Li, “Study of ultrathin vanadium nitride as diffusion barrier for copper interconnect”, Microelectron. Eng., 83 (2006) 236-240.
[8] M.B. Takeyama, M. Sato, T. Itoi, E. Aoyagi, A. Noya, “Barrier properties of ultrathin VN films of low resistivity and high density for Cu interconnects”, Jpn. J. Appl. Phys., 50 (2016) 02BC10.
[9] G. Rampelberg, K. Devloo-Casier, D. Deduytsche, M. Schaekers, N. Blasco, C. Detavernier, “Low temperature plasma-enhanced atomic layer deposition of thin vanadium nitride layers for copper diffusion barriers”, Appl. Phys. Lett., 102 (2013) 111910.
[10] R. Lucio-Porto, S. Bouhtiyya, J.F. Pierson, A. Morel, F. Capon, P. Boulet, T. Brousse, “VN thin films as electrode materials for electrochemical capacitors“, Electrochim. Acta, 141 (2014) 203-211.
[11] B. Wang, Z. Chen, G. Lu, T. Wang, Y. Ge, “Exploring electrolyte preference of vanadium nitride supercapacitor electrodes”, Mater. Res. Bull., 46 (2016) 37-40.
[12] Q. Sun and Z.-W. Fu, “Vanadium nitride as a novel thin film anode material for rechargeable lithium batteries”, Electrochim. Acta, 54 (2008) 403-409.
[13] F. Ge, P. Zhu, F. Meng, Q. Xue, F. Huang, “Achieving very low wear rates in binary transition-metal nitrides: The case of magnetron sputtered dense and highly oriented VN coatings”, Surf. Coat. Technol., 248 (2014) 81-90.
[14] J. A. Thornton, “Influence of apparatus geometry and deposition conditions on the structure and topography of thick sputtered coatings”, J. Vac. Sci. Technol., 11 (1974) 666.
[15] R. Wuhrer, W. Y. Yeung, ”A study on the microstructure and property development of dc magnetron cosputtered ternary titanium aluminium nitride coatings - Part III - effect of substrate bias voltage and temperature”, J. Mater. Sci., 37 (2002) 1993-2004.
[16] C.K. Wu, Master Thesis, Department of Engineering System and Science, National Tsing Hua University, Taiwan, (R.O.C.), 2016.
[17] P.T. Shaffer, Plenum Press Handbooks of High-temperature Materials, No. 1, Plenum Press, New York, 1964.
[18] L.E. Toth, Transition Metal Carbides and Nitrides, 1st edition, Academic Press, New York, 1971.
[19] J. Zasadzinski, R. Vaglio, G. Rubino, K. E. Gray, M. Russo,”Properties of superconducting vanadium nitride sputtered films” Phys. Rev., B 32 (1985) 2929.
[20] Hugh O. Pierson, Handbook of Refractory Carbides and Nitrides, 1st edition, Noyes Publications, England, 1996.
[21] H. Okamoto, “N-V (Nitrogen-Vanadium)”, J. Phase Equilib., 22 (2001) 362-362.
[22] JCPDS file 65-0437
[23] Y. Qiu, S. Zhang, B. Li, J-W Lee, D. Zhao, “Influence of Nitrogen Partial Pressure and Substrate Bias on the Mechanical Properties of VN Coatings”, Procedia Eng., 36 (2012) 217-225.
[24] A.B. Mei, R.B. Wilson, D. Li, David G. Cahill, A. Rockett, J. Birch, L. Hultman, J.E. Greene, I. Petrov, “Elastic constants, Poisson ratios, and the elastic anisotropy of VN(001), (011), and (111) epitaxial layers grown by reactive magnetron sputter deposition”, J.Appl. Phys., 115 (2014) 214908.
[25] W.D Münz, “ Titanium aluminum nitride films: A new alternative to TiN coatings”, J. Vac. Sci. Technol., A 4 (1986) 2717.
[26] K. Kutschej, P.H. Mayrhofer, M. Kathrein, P. Polcik, C. Mitterer, “Influence of oxide phase formation on the tribological behaviour of Ti–Al–V–N coatings”, Surf. Coat. Technol., 200 (2005) 1731-1737.
[27] R. Franz, J. Neidhardt, B. Sartory, R. Kaindl, R. Tessadri, P. Polcik, V.H. Derflinger, C. Mitterer, “High-temperature low-friction properties of vanadium-alloyed AlCrN coatings”, Tribol. Lett., 23 (2006) 101-107.
[28] P.H. Mayrhofer, P.Eh. Hovsepian, C. Mitterer , W.D. Münz, “Calorimetric evidence for frictional self-adaptation of TiAlN/VN superlattice coatings”, Surf. Coat. Technol., 177-178 (2004) 341-347.
[29] O. Storz, H. Gasthuber, M. Woydt, “Tribological properties of thermal-sprayed Magnéli-type coatings with different stoichiometries (TinO2n-1)”, Surf. Coat. Technol., 140 (2001) 76-81.
[30] F.C. Walsh, R.G.A. Wills, “The continuing development of Magnéli phase titanium sub-oxides and Ebonex® electrodes”, Electrochim. Acta, 55 (2010) 6342-6351
[31] E. Lugscheider, O. Knotek, K. Bobzin, S. Bärwulf, “Tribological properties, phase generation and high temperature phase stability of tungsten- and vanadium-oxides deposited by reactive MSIP-PVD process for innovative lubrication applications”, Surf. Coat. Technol., 133-134 (2000) 362-368.
[32] G. Gassner, P.H. Mayrhofer, K. Kutschej, C. Mitterer, M. Kathrein, “A new low friction concept for high temperatures: lubricious oxide formation on sputtered VN coatings”, Tribol. Lett., (2004) 751-755.
[33] P.J. Kelly, R.D. Arnell, “Magnetron sputtering: A review of recent developments and applications”, Vacuum, 56 (2000) 159-172.
[34] R.D. Arnell, P.J. Kelly, “Recent advances in magnetron sputtering”, Surf. Coat. Technol., 112 (1999) 170-176.
[35] J. Musil, V. Poulek, “Relation of deposition conditions of Ti—N films prepared by d.c. magnetron sputtering to their microstructure and macrostress”, Surf. Coat. Technol., 60 (1993) 484-488.
[36]B. A. Movchan, A . V. Demchishin, “Study of structure and properties of thick vacuum condensates of nickel, titanium, tungsten, aluminium oxide and zirconium dioxide”, Phys. Met. Metallogr., 28 (1969) 83-90.
[37] J.A. Thornton, “High rate thick film growth”, Ann. Rev. Mater. Sci., 7 (1977) 239-260.
[38] J.A. Thornton, V.L. Hedgcoth, “Tubular hollow cathode sputtering onto substrates of complex shape”, J. Vac. Sci. Technol., 12 (1975) 93.
[39] J.A. Thornton, D.W. Hoffman, “Stress-related effects in thin films”, Thin Solid Films., 171 (1989) 5-31.
[40] R. Messier, A.P. Giri, R.A. Roy, “Revised structure zone model for thin film physical structure”, J. Vac. Sci. Technol., A 2 (1984) 500.
[41] A. Anders, “A structure zone diagram including plasma-based deposition and ion etching”, Thin Solid Films, 518 (2010) 4087-4090.
[42] B. Warcholinski, A. Gilewicz, J. Ratajski, Z. Kuklinski, J. Rochowicz, ”An analysis of macroparticle-related defects on CrCN and CrN coatings in dependence of the substrate bias voltage”, Vacuum, 86 (2012) 1235-1239.
[43] B. Tlili, N. Mustapha, C. Nouveau, Y. Benlatreche, G. Guillemot, M. Lambertin, “Correlation between thermal properties and aluminum fractions in CrAlN layers deposited by PVD technique”, Vacuum, 84 (2010) 1067-1074.
[44] J.H. Huang, K.J. Yu, P. Sit, G.P. Yu, ”Heat treatment of nanocrystalline TiN films deposited by unbalanced magnetron sputtering”, Surf. Coat. Technol., 14-15 (2006) 4291-4299.
[45] Y. Cheng, B. Tay, S. Lau, X. Shi, “Influence of substrate bias on the structure and properties of (Ti, Al) N films deposited by filtered cathodic vacuum arc”, J. Vac. Sci. Technol., A 19/3 (2001) 736.
[46] I. Petrov, L. Hultman, J.E. Sundgren, J. Greene,”Polycrystalline TiN films deposited by reactive bias magnetron sputtering - effects of ion-bombardment on resputtering rates, film composition, and microstructure” J. Vac. Sci. Technol., A 10/2 (1992) 265-272.
[47] B. Warcholinski, A. Gilewicz, ”Effect of substrate bias voltage on the properties of CrCN and CrN coatings deposited by cathodic arc evaporation”, Vacuum, 90 (2013) 145-150.
[48] Y. X. Wang, S. Zhang, J.W. Lee, W. S. Lew, B. Li, ”Influence of bias voltage on the hardness and toughness of CrAlN coatings via magnetron sputtering”, Surf. Coat. Technol., 206 (2012) 5103-5107.
[49] J.P. Zhao, X. Wang, Z.Y. Chen, S.Q. Yang, T.S. Shi, X.H. Liu, ”Overall energy model for preferred growth of TiN films during filtered arc deposition”, J. Phys. D: Appl. Phys., 30 (1997) 5-12.
[50] J.E. Greene, J.E. Sundgren, L. Hultman, I. Petrov, ”Development of preferred orientation in polycrystalline TiN layers growth by ultrahigh-vacuum reactive magnetron sputtering”, D.B. Bergstrom, Appl. Phys. Lett., 67 (1995) 2928.
[51] J.E. Greene, Handbook of Crystal Growth, vol. 1, Elsevier, Amsterdam, 1993.
[52] S. Zhang, D. Sun, Y. Fu, H. Du, “Toughening of hard nanostructural thin films: a critical review“, Surf. Coat. Technol., 198 (2005) 2-8.
[53] P. Patsalas, C. Charitidis, S. Logothetidis, ”The effect of substrate temperature and biasing on the mechanical properties and structure of sputtered titanium nitride thin films”, Surf. Coat. Technol., 125 (2000) 335-340.
[54] Q. Konga, L. Ji , H. Li, X. Liua, Y. Wanga, J. Chen, H. Zhou, “Influence of substrate bias voltage on the microstructure and residual stress of CrN films deposited by medium frequency magnetron sputtering“, Mater. Sci. Eng., B 176 (2011) 850-854.
[55] C. Gautier, H. Moussaoui, F. Elastner, “Comparative study of mechanical and structural properties of CrN films deposited by d.c. magnetron sputtering and vaccum arc evaporation“, J. Machet, Surf. Coat. Technol., 86-87 (1996) 254-262.
[56] M. Ahlgren, H. Blomqvist, “Influence of bias variation on residual stress and texture in TiAlN PVD coatings“, Surf. Coat. Technol., 200 (2005) 157-160.
[57] J.H. Huang, C.Y. Hsu, S.S. Chen, G.P. Yu, “Effect of substrate bias on the structure and properties of ion-plated ZrN on Si and stainless steel substrates“, Mater. Chem. Phys., 77 (2002) 14-21.
[58] D.A. Shirley, “High-Resolution X-Ray Photoemission Spectrum of the Valence Bands of Gold”, Phys. Rev., B 5 (1972) 4709.
[59] M.Y. Liao, Y. Gotoh, H. Tsuji, J. Ishikawa, “Crystallographic structure and composition of vanadium nitride films deposited by direct sputtering of a compound target”, J. Vac. Sci. Technol., A 22 (2004) 146-150.
[60] R.T. Haasch, T.-Y. Lee, D. Gall, J.E. Greene, I. Petrov, “Epitaxial VN (001) Grown and Analyzed In situ by XPS and UPS. I. Analysis of As-deposited Layers”, Surf. Sci. Spectra, 7 (2000) 221-232.
[61] A.M. Glushenkov, D. Hulicova-Jurcakova, D. Llewellyn, G.Q. Lu, Y. Chen, “Structure and Capacitive Properties of Porous Nanocrystalline VN Prepared by 81 Temperature-Programmed Ammonia Reduction of V2O5”, Chem. Mater., 22 (2010) 914-921.
[62] Z. Zhao, Y Liu, H Cao, J Ye, S Gao, M Tu, “Synthesis of VN nanopowders by thermal nitridation of the precursor and their characterization”, J. Alloys Compd., 464 (2008) 75-80.
[63] J.G. Choi, “The surface properties of vanadium compounds by X-ray photoelectron spectroscopy”, Appl. Surf. Sci., 148 (1999) 64-72.
[64] P. Scherrer, “Bestimmung der Grösse und der innern Struktur von Kolloidteilchen mittels Röntgenstrahlen“, Gött. Nachr., 2 (1918) 98-100.
[65] JCPDS file 22-1058
[66] JCPDS file 33-1439
[67] L.V. Azároff, M.J. Buerger, The powder method in X-ray crystallography, McGraw-Hill, New York ,1958.
[68] J. Dean, J.M. Wheeler, T.W. Clyne, “Use of quasi-static nanoindentation data to obtain stress–strain characteristics for metallic materials”, Acta Materialia, 58 (2010) 3613-3623.
[69] W.C. Oliver, G.M. Pharr, “An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments”, J. Mater. Res., 7 (1992) 1564-1583.
[70] G.G. Stoney, “The tension of metallic films deposited by electrolysis”, Proc. Roy. Soc. Lond. A Mat., 82 (1909) 172-175.
[71] W. Nix, “Mechanical properties of thin films”, Metall. Trans., A 20 (1989) 2217-2245.
[72] S.M. Sze, VLSI technology, McGraw-Hill, New York, 1983.
[73] CIE, Colorimetry, Tech. Rept., 15, Bureau Central de la CIE, Paris, 1971.
[74] CIE, Recommendations on uniform color spaces, color difference equation and psychometric terms, Supplement No.2 to CIE publication No.15, Tech. Rept., Bureau Central dela CIE, Paris, 1978.
[75] ASTM, Symposium on Color, American Society for Testing Materials, American Society for Testing Materials, Philadelphia, 1941.
[76] R. F. Bunshah, R. S. Juntz,“Influence of condensation temperature on microstructure and tensile properties of titanium sheet produced by high-rate physical vapor process“, Metall. Trans., 4 (1973) 21-26.
[77] H. Oettel, R. Wiedemann, S. PreiBler, “Residual stresses in nitride hard coatings prepared by magnetron sputtering and arc evaporation“, Surf. Coat. Technol., 74-75 (1995) 273-278.
[78] R. Hull, Properties of crystalline silicon, the Institution of Electrical Engineers, London, 1999.
[79] O. Knotek, R. Elsing, G. Krämer, F. Jungbult, “On the origin of compressive stress in PVD coatings — an explicative model”, Surf. Coat. Technol., 46 (1991) 265.
[80] P.B. Barna, M. Adamik, “Fundamental structure forming phenomena of polycrystalline films and the structure zone models” Thin Solid Films, 317 (1998) 27-33.
[81] S. Mukherjee, F. Prokert, E. Richter, W. Moeller, “Compressive stress, preferred orientation and film composition in Ti-based coatings developed by plasma immersion ion implantation-assisted deposition“, Surf. Coat. Technol., 186 (2004) 99.
[82] J.M. Yu, R. Trivedi, “Surface self-diffusion studies on the (111) surface of vanadium”, Surf. Sci., 125 (1983) 396-408.
[83] M. Ohring, The Material Science of Thin Films, Academic Press, New York, 1992.
[84] J. W. Lee, S. K. Tien, Y. C. Kuo, ”The effects of substrate bias, substrate temperature, and pulse frequency on the microstructures of chromium nitride coatings deposited by pulsed direct current reactive magnetron sputtering”, J. Electron. Mater., 34 (2005) 12.
[85] S. Zhang, H.L. Wang, S.E. Ong, D. Sun, X.L. Bui, ”Hard yet Tough Nanocomposite Coatings – Present Status and Future Trends”, Plasma Process Polym., 4 (2007) 219.
[86] W.J. Chou, G.P. Yu, J.H. Huang, ”Deposition of TiN thin films on Si(100) by HCD ion plating”, Surf. Coat. Technol., 140 (2001) 206.
[87] L. Hultman, M. Shinn, P. Mirkarimi, S. Barnett, “Characterization of misfit dislocations in epitaxial (001)-oriented TiN, NbN, VN, and (Ti,Nb)N film heterostructures by transmission electron microscopy”, J. Cryst. Growth, 135 (1994) 309-317.
[88] H. Ljungcrantz, M. Odén, L. Hultman, J. E. Greene, J. E. Sundgren, “Nanoindentation studies of single‐crystal (001)‐, (011)‐, and (111)‐oriented TiN layers on MgO”, J. Appl. Phys., 80 (1996) 6725-6733.
[89] Q.Y. Chen, Master Thesis, National Tsing Hua University, Taiwan, R.O.C., 2012.
[90] J.D. Eshelby, F.C. Frank, F.R.N. Nabarro, “The equilibrium of linear arrays of dislocations”, Philos. Mag., 42 (1951) 351-364.
[91] G.E. Dieter, D. Bacon, Mechanical metallurgy, McGraw-Hill, New York, 1986.
[92] I.A. Ovid’ko, ” Deformation of Nanostructures”, Science, 295 (2002) 2386.