鎳矽化合物NiSi是目前最具潛力的金屬矽化物材質，它具有相當多的優點，但其缺點是熱穩定不足。本實驗針對此缺點，嘗試用氮離子佈植的方法去改善。並希望能同時減少漏電流以及改善MOSFETs的電性。
論文的主題分成三個部份: 首先探討用氮離子佈植法去改善NiSi的熱穩定性，再來探討氮離子佈植對NiSi漏電流的影響。最後探討把此法用於MOSFETs元件時，其電性的表現。

在熱穩定性方面，實驗發現氮離子佈植後確實有改善。NiSi熱穩定不足的原因是當其在750°C高溫時會轉成高阻值的NiSi2，而氮離子能有效的減緩其轉換的速度。在漏電流方面也有明顯的改善，原因是氮離子可以防止氧原子的入侵以及減少鎳原子的擴散速度，使得NiSi薄膜和矽基板的界面較為平滑，漏電流也因而減少。對於用在整個MOSFETs元件上時，發現氮離子的佈植可以增強其對熱載子注入(Hot-Carrier Stress)的抗性。因為氮離子在高溫時會擴散至閘極氧化層和矽基板的界面，修補不完整的鍵結，並和矽原子結合形成較強的鍵結，提升了元件的可靠度。

【參考文獻】
[1] T. Morimoto, T. Ohguro, S. Momose, T. Iinuma, I. Kunishima, K. Suguro, I. Katakabe, H. Nakajima, M. Tsuchiaki, M. Ono, Y. Katsumata, H. Iwai, “Self-aligned nickel-mono-silicide technology for high-speed deep submicrometer logic CMOS ULSI,” IEEE Transactions on Electron Devices, vol. 42, pp. 915, 1995.
[2] K. C. Sawaswat and F. Mohammadi, “Effect of Scaling of Interconnections on the Time Delay of VLSI Circuits,” IEEE Trans. Electron Devices, vol. 29, no. 4, pp. 645, 1982.
[3] D. B. Scott, W. R. Hunter and H. Shichijo, “A Transmission Line Model for Silicided Diffusions: Impact on the Performance of VLSI Circuits,” IEEE Trans. Electron Devices, vol. 29, no. 4, pp. 651, 1982.
[4] C. T. Chuang, M. Arienzo, D. D. Tang and R. D. Isaac, “A Schottky-Barrier Diode with Self-Aligned Floating Guard Ring,” IEEE Trans. Electron Devices, vol. 31, no. 10, pp. 1482, 1984.
[5] S. Tohyama, K. Masubuchi, K. Konuma, H. Azuma, “A High Fill Factor and Progressive Scan PtSi Schottky-Barrier IR-CCD Image Sensor Using New Wiring Technology,” IEEE Trans. Electron Devices, vol. 42, pp. 1433, 1995.
[6] Stanley Wolf, “ Silicon Processing For the VLSI Era” vol. 2, p143-p147
[7] D. M. Brown, W. E. Engeler, M. Garfinkel, and P. V. Gray, “Self-aligned molybdenum gate MOSFETs,” J. Electrochem. Soc., vol. 115, pp. 874, 1968.
[8] K. L. Wang, T. C. Holloway, R. F. Pinizzotto, A. P. Sobczak, W. R. Hunter and A. F. Tash, ” Composite TiSi2 / n+ Poly-Si Low- Resistivity Gate Electrode and Interconnect for VLSI Device Technology,” IEEE Trans. Electron Devices, vol. 29, no. 4, pp. 547, 1982.
[9] J. C. Barbour, A. E. M. J. Fischer and J. F. van deer Veen, “The thin-film reaction between Ti and thermally grown SiO2,” J. Appl. Phys., vol. 62, pp.2582, 1987.
[10] Jerome B. Lasky, James S. Nakos, Orison J. Cain, and P. J. Geiss, “ Comparison of Transformation to Low- Resistivity Phase and Agglomeration of TiSi2 and CoSi2,” IEEE Trans. Electron Devices, vol. 38, pp. 262, 1991.
[11] N. S. Parekh, H. Roede, A. A. Bos, A. G. M. Jonkers, and R. D. J. Verhar, “Characterization and implementation of self-aligned TiSi2 in submicrometer CMOS technology,” IEEE Trans. Electron Devices, vol. 38, pp. 88, 1991.
[12] T. Ohurgo, S. Nakamura, M. Koike, T. Morimoto, A. Nishiyama, “Analysis of resistance behavior in Ti and Ni salicide polysilicon films,” IEEE Electron Devices Letters, vol. 15, pp. 342, 1994.
[13] Tohru Mogami, Hitoshi Wakabayashi, “Low-resistance self -aligned Ti silicide technology for Sub-Quarter micro CMOS devices,” IEEE Trans. Electron Devices, vol. 43, pp. 932, 1996.
[14] G. T. Sarcona, M. Stewart, M.K. Hatalis, “Polysilicon thin-film transistors using self-aligned cobalt and nickel silicide source and drain contacts,” IEEE Electron Device Letters, vol. 20, Issue: 7, pp. 332, 1999.
[15] W.T. Sun, M.C. Liaw, “Suppression of cobalt silicide agglomeration using nitrogen(N2+) implantation,” IEEE Electron Device Letters, vol. 19, pp. 163, 1998.
[16] S. R. Das, D. X. Xu, M. Nournia, L. Lebrun, A. Naem, “Thermal Stability of nickel silicide films,” Mat. Res. Soc. Symp. Proc. , vol. 427, pp. 541, 1996.
[17] M. C. Poon, F. Deng, M. Chan, W. Y. Chan, S. S. Lau, “Resistivity and thermal stability of nickel mono-silicide,” Applied Surface
Science, vol. 157, pp. 29, 2000.
[18] M. C. Poon, M. Chan, W. Q. Zhang, F. Deng, S. S. Lau, “Stability of NiSi in boron-doped polycilicon lines,” Microelectronics Reliability, vol. 38, pp. 1499, 1998.
[19] T. Ohguro, S. Nakamura, E. Morifuji, M. Ono, T. Yoshitomi, M. Saito, H. S. Momose, Iwai, H. ,“Nitrogen-doped nickel mono-silicide technique for deep submicron CMOS salicide,” in IEDM Tech, Dig., pp. 453 ,1995.
[20] K.-I. Goto, J. Watanabe, T. Sukegawa, A. Fushida, T. Sakuma, T. Sugii, T, “A comparative study of leakage mechanism of Co and Ni salicide processes,” Reliability Physics Symposium Proceedings, pp.363, 1998.
[21] T. H. Hou, T. F. Lei, and T. S. Chao, ”Improvement of Junction Leakage of Nickel Silicided Junction by a Ti-Capping Layer,” IEEE Electron Device Letter, vol. 20, no. 11, pp. 572, 1999.
[22]T. Ohguro, T. Morimoto, Y. Ushiku, H. Iwai,EXT. Abst. SSDM,
Makuhari,p.192,1993
[23]S. Ogawa, T. Kousaki, T.Youshida and R. Sinclair, J. Appl. Phys.,70(1991)p827
[24] L. W. Cheng, S. L. Cheng, J. Y. Chen, L. I. Chen, B.Y Tsui, “ Formation of Nickel Silicide on Nitrogen implanted Silicon,” Thin Solid Films, vol. 355-356, pp. 412-416, 1999.
[25] L. W. Cheng, J. Y. Cheng, J. C. Chen, S. L. Cheng, L. J. Chen, B.Y. Tsui,“Formation of Nickel Silicide on Nitrogen Ion Implanted Silicon,” Ion Implantation Technology Proceedings, 1998 International Conference on, vol. 2 ,pp. 1002, 1998
[26]T. S. Chao, C.H. .Chien, C. P. Hao, M. C. Liaw, C. H. Chu, C. Y. Chang, T. F. Lei, W. T. Sun and C. H. Hsu, “Suppression of Boron Penetration in P+-Poly-Si Gate Metal-Oxide-Semiconductor Transistor Using Nitrogen Implantation” Jpn. J. Appl. Phys. vol.36, pp.1364, 1997.
[27]X. G. Xiao,J. W. Honeycutt and G. A.Rozonyi,Materials Research
Soc.(1991)p259
[28]X. G. Xiao,J. W. Honeycutt and G. A.Rozonyi,Materials Research Soc.(1991)p429
[29]C. Dehm,I.Kasko,E. P.Burte,J. Gyulai and H. Ryssel,Appl. Surf. Sci.,73(1993)p268
[30]M. Liehr,F. K. LeGoues,G. W. Rubloff and P. S. Ho,J. Vac. Sci. Technol.,A3(1985)p983
[31]J. Amano, K. Nauka, M. P. Scott and J. E. Turner, Appl. Phys. Lett.,49(1986)p737
[32]K. Nauka,J. Amano,M. P. Scott,E. R. Weber, Materials Research Sco.,(1992)p429
[33] Goto, K.-I.; Watanabe, J.; Sukegawa, T.; Fushida, A.; Sakuma, T.; Sugii, T. Reliability Physics Symposium Proceedings, 1998. 36th Annual. 1998 IEEE International , 1998 ,Page(s): 363 –369
[34]K. Ohyu, M. Ohkura, A. Hiraiwa and K. Watanabe, IEEE Trans. Electron Devices,42(1995)p1404
[35]F. M. d`Heurle and P. Gas, J. Mater. Res.,1(1986)p205
[36] E. G. Colgan,J. P. Gambino and Q. Z. Hong,Mater. Sci. Eng.,R16(1996)p43
[38] A. Furukawa, Y. Abe, S. Shimizn, T. Kuroi, Y. Tokuda and M. Inuishi, Sym on VLSI Tech. Dig., 1996.
[39] H. Hwang, W. Ting, D.L. Kwong and J. Lee, in IEDM Tech. Dig, p. 421, 1990.
[40] C. T. Liu, Ma, J. Becerro, S. Nakahara, D. J. Eaglesham, S. J. Hillenius, “Light Nitrogen Implant for Preparing Thin-Gate Oxides”, IEEE, 1997.
[41]Y.Y. Chen, I. M. Gardner, J. Fulford, D. L. Kwong, Tech.Dig. IEDM(1997)p639
[42]Bikas Maiti Philip J. Tobin, Veena Misra, Rama I. Hegde, Tech. Dig. IEDM(1997)p651
[43]Chao Sung Lai, Tien Sheng Chao, Tan Fu Lei, Chung Len Lee,Tiao Yuan Huang, Chun Yen Chang,JJAP,Vol.37(1998)p5507
[44]C.G.Parker, G. Lucovsky, J.R. Hauser,IEEE EDL,vol.19,No.4(1998)p106