臺灣博碩士論文加值系統

在第一部份的實驗中，我們對鐵矽系統的應力變化和固態反應作了詳細的研究，我們在應力圖形中發現了兩個主要的變化曲線，分別位於400 ℃和600℃附近，這兩個應力變化分別來自於FeSi相和β-FeSi2相的形成。FeSi相形成於鐵薄膜和矽基材的界面處，同時FeSi相的生成受到表面的非晶質矽薄膜相當大的影響。在形成的過程中，有相當大的壓應力產生，此壓應力主要來自於鐵薄膜的非晶質化過程，在反應的最後階段有量測到較小的張應力，此張應力則是來自於鐵矽化物的相變化反應。β-FeSi2相的形成是屬於成核控制機制，主要的擴散元素是矽原子。反應在600 ℃以上有停滯的現象，推測是由於矽的擴散距離隨β-FeSi2相的成長而增長所導致的結果，應力量測上則沒有發現明顯的變化，然而由於造成的因素太複雜，很難加以討論。
第二部分的實驗是利用雙層的鐵矽薄膜合成矽化鉭的奈米線，共有三組條件分別是Ni (60nm)/Fe (3nm)/Si、Ni (3nm)/Fe (3nm)/Si和Ni (3nm)/Fe (60nm)/Si。矽化鉭的奈米線是在真空下升溫950℃持溫32小時所合成的，對於Ni (60nm)/Fe (3nm)/Si和Ni (3nm)/Fe (3nm)/Si系統而言，我們發現結構是以矽化鉭(TaSi2)為主，其中摻雜有少量的鐵和鎳，其成長方向是以(2-10)面向上堆疊。特別的是，在Ni (3nm)/Fe (60nm)/Si系統中發現高含量的鐵和鎳，藉由繞射圖形的判定，除了TaSi2以外沒有多餘的點存在，因此量測到的鐵和鎳是以隨機排列的形式存在於奈米線中，本實驗因此成功合成了摻雜有高含量鐵矽的矽化鉭奈米線。同時發現藉由矽化鐵奈米球所合成的奈米線主要結構也是矽化鉭，其高含量的鐵（超過15 %）也一樣是以隨機方式存在。我們同時還對各組條件做長度上的分析，發覺鍍磨條件中鐵的比例對合成長度有很大的影響，經由對基材所做的TEM觀察和成分分析，發覺主要是鐵和鎳矽化物影響奈米線的成長。就成長機制來說，此次合成的奈米線推測是以V-S (Vapor-Solid) 的方式合成，其中鉭蒸汽的來源主要來自於鉭燈絲，而由之前的長度效應分析，矽蒸汽的主要來源應該是鐵和鎳矽化物，其中鐵矽化物(FeSi2)的融點是1200℃而鎳矽化物(NiSi2)的溫度則是993℃，這解釋了為何鎳含量高的系統，奈米線較長。場發射結果發現摻雜有少量鐵和鎳的奈米線，功函數是和塊材相近的4.7eV，然而高摻雜的奈米線中，功函數有降低的現象，因此鐵的摻雜有降低功函數的效果。

In first part of our experiment, stress evolution and detail solid reaction process for Fe/Si system were provided. Two major curvature changes were found near 400 ℃ and 600 ℃, which is related to the transition of FeSi and β-FeSi2. FeSi forms at the interface between Fe film and Si substrate. The amorphous Si capping layer strongly affects the formation of FeSi phase. Large compressive stress was measured during the reaction, which is manly caused by the amorphorization of Fe film due to the diffusion of Si atoms. A small tensile stress was observed at the end of the FeSi transition (from 450 ℃ to 470 ℃) relating to the Fe to FeSi reaction. Nucleation-controlled growth mechanism was found for β-FeSi2. The nucleation site is at the interface between FeSi and Si substrate. The diffusion species is observed to be Si. The increase of diffusion distances cause the reaction retards above 600 ℃. No obvious stress change was found for the formation of β-FeSi2. However, the reason is too complex to give a detail study for it.
In second part, multilayer systems of Ni (60nm)/Fe (3nm)/Si, Ni (3nm)/Fe (3nm)/Si, and Ni (3nm)/Fe (60nm)/Si were used to synthesized tantalum silicide nanowires via vacuum annealing under 950 ℃ for 32 hr. For Ni (60nm)/Fe (3nm)/Si system and Ni (3nm)/Fe (3nm)/Si, TaSi2 wires with small amounts of Fe and Ni were observed. The growth direction is perpendicular to the (2-10) plane. Large concentration of Fe and Ni was found for Ni (3nm)/Fe (60nm)/Si. Owing to the absence of any extra points in the diffraction patterns, the Fe and Ni atoms should exist in a random form. Thus the Fe and Ni doped TaSi2 wires were acquired. The wires with high concentration of Fe (over 15%) induced by Fe dots system are also identified to be TaSi2. Length effect for every different condition was analyzed, and the wire length is highly affected by the Fe concentration. Cross-sectional TEM images of three different substrates show that Fe and Ni disilicides are the keys to the wire growth. The well-known Vapor-Solid (VS) mechanism is the possible candidate. Ta source is provided by Ta filament and the Si source is mainly from Fe and Ni disilicides due to the study of length effect. The melting points of FeSi2 and NiSi2 are 1200 ℃ and 993 ℃, which explains the longer wire obtained by the Ni rich system. Field Emission results show that the work function of wires with small amounts of Fe and Ni is about 4.7eV, which is similar to the bulk. A decrease of work function (2.39eV) was found for the Fe rich system. We also obtain the same result for the Fe dots system. Therefore, the adulteration of Fe atoms will reduce the work function of TaSi2 wire.

Chapter 1 Introduction……………………………………………5
1-1 Stress Evolution of Fe/Si(001) system under isochronal annealing (Part 1)……………………………………………………………………5
1-1.1 The application of silicide ……………………5
1-1.2 The property of iron silicide ……………………6
1-1.3 The growth kinetics ……………………………………10
1-1.4 The theory and influence of film stress ………13
1-1.5 Motivation……………………………………16
1-2 The synthesis of Fe and Ni doped TaSi2 wires (Part 2)…………………17
1-2.1 The introduction of nanowires …………………17
1-2.2 The discovery of tantalum silicide nanowires ………………………18
Chapter 2 Experimental Procedures…………………………20
2-1 Experiments of Stress Evolution (Part 1)…………………………………20
2-1.1 Sample preparation and wafer cleaning …………21
2-1.2 The deposition of thin iron film …………………21
2-1.3 Sample preparation for in-situ curvature measurement……………22
2-1.4 In-situ curvature measurement ……………………23
2-1.5 Phase identification by grazing incidence X-Ray Diffraction ………24
2-1.6 Transmission Electron Microscope (TEM observation)……………24
2-1.7 Sample preparation for Transmission Electron Microscope…………25
2-1.8 Auger Electron Spectroscopy (AES)…………………………………27
2-2 Experiments of TaSi2 nanowires (Part 2)…………………………………28
2-2.1 Silicon wafer cleaning ………………………29
2-2.2 Thin film deposition …………………………………29
2-2.3 Heat treatment…………………………………30
2-2.4 Scanning Electron Microscope (SEM)…………………30
2-2.5 Energy Dispersive Spectrometer (EDS) Analyses…………………31
2-2.6 Transmission Electron Microscopy Observation ……………………31
2-2.7 Preparation of the Samples for TEM Observation……………………31
2-2.8 Field Emission measurement………………………………………33
2-2.9 Electrical Property measurement …………………33
Chapter 3 Results and Discussion ………………………35
Part 1 Stress Evolution of Fe/Si(001) system under isochronal annealing
3-1 The deposition property of as-deposited sample …………………………35
3-2 In-situ curvature evolution ……………………35
3-3 XRD results and phase identification …………37
3-4 The discussion of FeSi phase …………………37
3-4.1 The microstructure discussion during the FeSi phase transition ……37
3-4.2 The schematic model for FeSi solid reaction process ………………40
3-4.3 Stress effect during the FeSi formation ………42
3-5 The discussion of β-FeSi2 phase ………………43
3-5.1 The microstructure discussion during the β-FeSi2 transition…43
3-5.2 The schematic model for β-FeSi2 solid reaction process……………47
3-5.3 Stress effect during the β-FeSi2 formation……………………47
Chapter 4 Results and Discussion……………………………49
Part 2 The synthesis of Fe and Ni doped TaSi2 wires
4-1 Microstructure analysis of Fe-Ni tantalum silicide nanowires………49
4-1.1 Ni (60nm)/Fe (3nm) /Si system …………………………………49
4-1.2 Ni (3nm)/Fe (3nm) /Si system……………………………………50
4-1.3 Ni (3nm)/Fe (60nm)/ Si system………………………………………51
4-1.4 The composition analysis of the nanowire…………………………52
4-1.5 The dopping effect on TaSi2 wires…………………………………53
4-1.6 The Fe and Ni doped TaSi2 wires……………………………………54
4-2 The Discussion of wire growth……………………………………………55
4-2.1 The length effect on wire growth ……………55
4-2.2 Substrate analysis for multilayer system ………56
4-2.3 The mechanisms of wire growth…………………58
4-3 Field Emission property…………………61
4-4 Results of Electrical Property …………………64
Chapter 5 Summary and conclusions……………………66
Reference…………………………………………………………70
Figure caption………………………………………………79
Table…………………………………………………………86

Chapter 1
[1] M.G. Mendez, F.F. Castillon, G. A. Hirata, M. H. Farias, and G. Beamson, “XPS and HRTEM Characterization of Cobalt-Nickel Silicide Thin Films”, Applied Surface Science 161, 61-73 (2000).
[2] Castor Fu, M. P. C. M. Krijn, and S. Doniach, “ Electronic structure and optical properties of FeSi, a strongly correlated insulator”, Physical Review B 49 (3), 2219 – 2222(1993).
[3] V. Jaccarino et al, “Paramagnetic Excited State of FeSi”, Phys. Rev. 160, 476 (1967).
[4] K. Tajima, Y. Endoh, J. Fisher, and G. Shirane, “Spin fluctuations in the temperature-induced paramagnet FeSi”, Phys. Rev. B 38, 6954(1988)
[5] R. Moons, S. Degroote, J. Dekoster, A. Vantomme, and G. Langouche, “Structural characterization of metastable FeSi films and of Fe/FeSi multilayers”, Nucl. Instr. and Meth. in Phys. Res. B 136-138, 268-272 (1998).
[6] E.E. Fullerton, J. E. Mattson, S. R. Lee, C. H. Sowers, Y. Y. Huang, G. Felcher, S. D. Bader, “Magnetic decoupling in sputtered Fe/Si superlattices and multilayers”, J. Appl. Phys. 73, 6335 (1993).
[7] H. Lange, “”Phys. Status Solidi B 201, 3 (1997).
[8] Steffen Wagner, Ettore Carpene, Peter Schaaf, and Martin Weisheit, “ Formation of β-FeSi2 by excimer laser irradiation of Fe/Si bilayers”, Applied Surface Science 186, 156-161 (2002).
[9] M. C. Bost and J. E. Mahan, “Optical properties of semiconducting iron disilicide thin films”, J. Appl. Phys. 58, 2696 (1985).
[10] M. C. Bost and J. E. Mahan, “”, J. Vac. Sci. & Technol. B4, 1336 (1986).
[11] N. E. Christensen, “Electronic structure of beta -FeSi2”, Phys. Rev. B 42, 7148 (1990).
[12] M. Hansen and K. Anderko, “ Constitution of Binary Alloys, 2nd edn.”, McGraw-Hill, New York, p 7139 (1958).
[13] S.S. Lau etc., “Iron Silicide Thin Film Formation at Low Temperatures”, Thin Solid Films, 22, 415-422 (1975).
[14] H. C. Cheng, T. R. Yew, and L. J. Chen, “Interfacial reactions of iron thin films on silicon”, J. Appl. Phys. 72, 5905 (1985).
[15] H. C. Cheng, T. R. Yew, and L. J. Chen, “Interfacial Reactions of Iron Thin Films on Silicon”, J. Appl. Phys. 57(12), 5246-5250 (1985) .
[16] J. M. Gallego and R. Miranda, “The Fe/Si(100) interface”, J. Appl. Phys. 69, 1377 (1991).
[17] J. Alvarez, J. J. Hinarejos, E. G. Michel, J. M. Gallego, A. L. Vazquez de Parga, J. De la Figuera, C. Ocal, and R. Miranda, “Surface characterization of epitaxial, semiconducting, FeSi2 grown on Si(100)”, Appl. Phys. Lett. 59, 99 (1991).
[18] Q. G. Zhu, H. Iwasaki, E. D. Williams, and R. L. Park, “Formation of iron silicide thin films”, J. Appl. Phys. 60, 2629 (1986).
[19] G. Aeppli and Z. Fisk, Comments Condens. Matter Phys. 16, 155 (1992).
[20] D. Mandrus et al., “Thermodynamics of FeSi”, Phys. Rev. B 51, 4769 (1995).
[21] E. E. Fullerton, S. D. Bader, “Temperature-dependent biquadratic coupling in antiferromagnetically coupled Fe/FeSi multilayers”, Phys. Rev. B 53, 5112 (1996).
[22] A. Chaiken and R. P. Michel, M. A. Wall, “Structure and magnetism of Fe/Si multilayers grown by ion-beam sputtering”, Phys. Rev. B 53, 5518 (1996).
[23] J. Kohlhepp, M Valkier, A. van der Graaf, F. J. A. den Broeder, “Mimicking of a strong biquadratic interlayer exchange coupling in Fe/Si multilayers”, Phys. Rev. B 55, 696 (1997).
[24] Y. Tomm, L. Ivaneko, K. Irmscher, St. Brehme, W. Henrion, I. Sieber, and H. Lange, “Effects of doping on the electronic properties of semiconducting iron disilicide“, Material science and engineering B 37. 215-218 (1996).
[25] S. Eisebitt, J.–E. Rubensson, M. Nicodemus, T. Böske, S. Blügel, W. Eberhardt, K. Radermacher, S. Mantl, and G. Bihlmayer, “Electronic structure of buried alpha -FeSi2 and beta -FeSi2 layers: Soft-x-ray-emission and -absorption studies compared to band-structure calculations”, Phys. Rev. B 50, 18330 (1994).
[26] L. Migilo and G. Malegori, “Origin and nature of the band gap in beta -FeSi2”, Phys. Rev. B 52, 1448 (1995).
[27] A. B. Filonov, D. B. Migas, V. L. Shapohnikov, N. N. Dorozhkin, and G. V. Petrov, “Electronic and related properties of crystalline semiconducting iron disilicide”, J. Appl. Phys. 79 (10), 7708 (1996).
[28] V. N. Antonov, O. Jepsen, W. Henrion, M. Rebien, P. Stauß, and H. Lange, “Electronic structure and optical properties of beta -FeSi2”, Phys. Rev. B 57, 8934 (1998).
[29] A. B. Filonov, D. B. Migass, V. L. Shaposhnikovv, V. E. Borisenko, W. Henrion, M. Rebien, P. Stauss, and H. Lange, “Theoretical and experimental study of interband optical transitions in semiconducting iron disilicide”, J. Appl. Phys. 83, 4410 (1998).
[30] S. J. Clark, H.M. Al-Allak, S. Brand, and R.A. Abram, “Structure and electronic properties of FeSi2”, Phys. Rev. B 58, 10389 (1998).
[31] L. Miglio and V. Meregalli, “Theory of FeSi2 direct gap semiconductor on Si(100)”, J. Vac. Sci. Technol. B 16, 1604 (1998).
[32] Leo Migilo, V. Meregalli, and O. Jepsen, “Strain dependent gap nature of epitaxial β-FeSi2 in silicon by first principles calculations”, Appl. Phys. Lett. 75, 385 (1999).
[33] C. A. Dimitriadis, J. H. Werner, S. Logothetidis, M. Stutzmann, J. Weber, and R. Nesper, “Electronic properties of semiconducting FeSi2 films”, J. Appl. Phys. 68, 1726 (1990).
[34] W. M. Duncan, P.-H. Chang, B.-Y. Mao, and C.-E. Chen, “Photoluminescence and microstructural properties of high-temperature annealed buried oxide silicon-on-insulator”, Appl. Phys. Lett. 51, 773 (1987).
[35] S. Fukat, Y. Mera, M. Inoue, K. Maeda, H. Akiyama, and H. Sasaki, “Time-resolved D-band luminescence in strain-relieved SiGe/Si”, Appl. Phys. Lett. 68, 1889 (1996).
[36] A. G. Birdwell, R. Glosser, D. N. Leong, and K. P. Homewood, “Raman investigation of ion beam synthesized β-FeSi2”, J. Appl. Phys. 89, 965 (2001).
[37] K. Radermacher, S. Mantl, C. Dieker, H. Luth, and C. Freiburg, “Growth kinetics of iron silicides fabricated by solid phase epitaxy or ion beam synthesis”, Thin Solid Films 215, 76 (1992).
[38] C. A. Dimitriadis and J. H. Werner, “Growth mechanism and morphology of semiconducting FeSi2 films”, J. Appl. Phys. 68, 93 (1990)
[39] J. F. Jongste, P. F. A. Alkemade, G. C. A. M. Janseen, and S. Radelaar, “Kinetic of the formation of C49 TiSi2 from Ti-Si multilayers as observed by in-situ stress measurements”, J. Appl. Phys. 74, 3869 (1993).
[40] S. P. Murarka, “Metallization: Theory and Practive for VLSI and ULSI”, Butterworth-Heinemann (1993).
[41] R. W. Hoffman, “Physiccs of Thin Films: Vol. 3”, Academic, New York (1996).
[42] P. P. Buaud, F. M. d’Heurle, E. A. Irene, B. K. Patmaik, and N. R. Parikh, “In situ strain measurement during the formation of platinum silicide films”, J. Vac. Sci. Technolo. B 9, 2536 (1991).
[43] J. F. jongste, O. B. Loopstra, G. C. A. M. Janseen, and S. Radelaar, “Elastic constants and thermal expansion coefficient of metastable C49 TiSi2”
[44] J. T. Pan and I. Blech, “In situ measurement of refractory metal silicides during sintering”, J. Appl. Phys. 55, 2874 (1984).
[45] C. J. Tsai and K. H. Yu, “Stress Evolution during isochronal annealing of Ni/Si system”, Thin Solid Films 350, 91 (1999)
[46] A. L. Shull and F. Spaepen, “Measurements of stress during vapor deposition of copper and silver thin films and multilayers”, J. Appl. Phys. 80, 6243 (1996).
[47] Younan Xia, Peidong Yang, Yugang Sun, Yiying Wu, Brian Mayers, Byron Gates, Yadong Yin, Franklin Kim, and Haoquan Yan, “One-dimensional Nanostructures: Synthesis, Characterization, and Applications,” Advanced Materials 15, 353 (2003).
[48] Huber, C. A.; Huber, T. E.; Sadoqi, M.; Lubin, J. A.; Manalis, S.; Parter, C. B. Science 263, 800 (1994)
[49] Y. J. Han, J. M. Kim and G. D. Stucky‚ “ Preparation of Noble Metal Nanowires Using Hexagonal Mesoporous Silica SBA-15,” Chem. Mater. 12, 2068 (2000).
[50] L. Sun, P. C. Searson, C. L. Chien, “Electrochemical deposition of nickel nanowire arrays in single-crystal mica films,” Appl. Phys. Lett. 74, 2803 (1999).
[51] Y. H. Tang, Y. F. Zhang, H. Y. Peng, N. Wang, C. S. Lee and S. T. Lee, “Si nanowires synthesized by laser ablation of mixed SiC and SiO2 powders,” Chem. Phys. Lett. 314, 16 (1999).
[52] Y. G. Guo, L. J. Wan, C. F. Zhu, D. L. Yang, D. M. Chen and C. L. Bai, “Ordered Ni-Cu Nanowire Array with Enhanced Coercivity,” Chem. Mater. 15, 664 (2003)
[53] H. Cao, Z. Xu, D. Sang, C. Tie, “Template Synthesis and Magnetic Behavior of an Array of Cobalt Nanowires Encapsulated in Polyaniline Nanotubules,” Adv. Mater. 13, 21 ( 2001)
[54] S. P. Murarka, M. H. Read, C. J. Doherty, D. B. Fraser, “Resistivities of thin film transition metal silicides,” Electrochem. Soc. 129, 293 (1982).
[55] C. A. Decker, R. Solanki, J. L. Freeouf, J. R. Carruthers and D. R. Evans, “Directed growth of nickel silicide nanowires,” Appl. Phys. Lett. 84, 1389 (2004).
Chapter 3
[1] Hansen and K. Anderko, “Constitution of Binary Alloys, 2nd edn.”, McGraw-Hill, New York, 1958, p. 713.
[2] S.S. Lau etc., “Iron Silicide Thin Film Formation at Low Temperatures”, Thin Solid Films, 22, 415 (1975).
[3] J. Alvarez, A. L. Vazquez de Parga, J. J. Hinarejos, J. de la Figuera, E. G. Michel, C. Ocal, and R. Miranda, “Initial Stages of the growth of Fe on Si(111) 7x7”, Phys. Rev. B 47, 16048 (1993).
[4] D. sander, A. Enders, and J. Kirshner, “Stress evolution during the growth of ultrathin layers of iron and iron silicide on Si(111)”, Appl. Phys. Lett. 67, 1833 (1995).
[5] S. P. Murarka, “Metallization: Theory and Practice for VLSI and ULSI”, Butterworth-Heinemann, (1993).
[6] W. Buckel, “Internal Stresses”, J. Vac. Sci. Tech. 6, 606 (1969).
[7] Victor E., “Semicondicing Silicides”, Borisenko,p68.
[8] N. R. Baldwin, and D. G. Ivey, “Low Temperature Iron Thin Films-silicon Reactions”, J. Mater. Sci. 31, 31 (1996).
[9] “Morphologies and growth modes of FeSi and layers plrepared by rapid thermail annealing, in: Silicide Thin Films- Fabrication, Properties, and Applications, edited by R. T. Tung, P. W. Pellegrini, L. H. Allen (MRS, Pittsburgh, Pennsylvania, 1996)”, pp373-378.
[10] Z. Yang, G. Shao, K. P. Homewood, K. J. Reeson, M. S. Finney, and M. Harry, ”Order domain boundaries in ion beam synthesized semiconducting FeSi2 layers”, Appl. Phys. Lett. 67(5),1995.
[11] G. Shao, K. P. Homewood.,“On the crystallographic characteristics of ion beam synthesized β-FeSi2”, Intermetallics 8, 1405 (2000).
[12] T. Arakawa, G. Shao, S. Makiuchi, T. Ono, H. Tatsuoka, H. Kuwabara, “TEM observation of (110),(101)/Si(111) layers grown by reactive deposition epitaxy in the presence of an Sb flux”, Journal of Crystal Growth 237-239 (2002) 249-253.
[13] H. C. Cheng, T.R. Yew, L. J. Chen, “Interfacial reactions of iron thin films on silicon”, J. Appl. Phys. 53, 6885 (1985).
[14] Q. G. Zhu, H. Iwaraki, E. D. Williams, R. Park, ”Formation of iron silicide thin films”, J. Appl. Phys. 60, 2629 (1986).
[15] C. A. Dimitriadis, J. H. Werner,“Growth mechanism and morphology of semiconducting FeSi2 films”, J. Appl. Phys. 68, 93 (1990).
[16] Karen Maex, Marc Van Rossum,“Metal Silicides”, IMEC, Leuven, Belgium, pp 279-289.
[17] J. F. Jongste, P. F. A. Alkemade, G. C. A. M. Janssen, and S. Radelaar, “Kinetics of the Formation of C49 TiSi2 from Ti-Si Multilayers as Observed by In Situ Sterss Measurements”, J. Appl. Phys., 74, 3869 (1993).
Chapter 4
[1] A. M. Morales, C. M. Liber, “A laser ablation method for the synthesis of crystalline semiconductor nanowires,” Science 279, 208 (1998).
[2] Y. Y. Wu, P. D. Yang,“ Direct Observation of Vapor-Liquid-Solid Nanowire Growth,” J. Am. Soc. 123, 3165 (2001).
[3] P. D. Yang and C. M. Liber,“ Nanostructured high-temperature superconductors : Creation of strong-pinning columnar defects in nanorod/superconductor composites,” J. Mater. Res. 12, 2981 (1997).
[4] Z. W. Pan, Z. R. Dai, Z. L. Wang, “Nanobelts of semiconducting oxides,” Science 291, 1947 (2001).
[5] Zhang, R. Q.; Lifshiz, Y.; Lee, S. T. ,“Oxide assisted growth of semiconducting nanowires,” Adv. Mater. 15, 637 (2003).
[6] Wang, N.; Zhang, Y. F.; Tang, Y. H.; Lee, C.S.; Lee, S. T.,“SiO2-enhanced synthesis of Si nanowires by laser ablation,”Appl. Phys. Lett. 73, 3902 (1998).
[7] Wu, J. J.; Yu, C. C. J.,“ Aligned TiO2 nanorods and nanowalls,” Phys. Chem. B 108, 3378 (2004).
[8] Y. D. Yin, D. G.. Zhang, Y. N. Xia, “ Synthesis and characterization of MgO nanowires through a vapor-phase precursor method,” Adv. Mater.12, 293 (2002).
[9] E. I. Givargizov, “Highly anisotropic crystals,” Terra Scientific Publishing, (1986)
[10] D. A. Porter and K. E. Easterling, “Phase transformations in matels and alloys,” Chapman Hall, (1981).
[11] Wang, Q. H.; Sethur, A. A.; Lauerhaas, M. J.; Dai, J. Y.; Seeling, E. W., “A nanotube based field-emission flat panel display,” Appl. Phys. Lett. 72, 2912 (1998).
[12] Fowler, R. H.; Nordheim, L. W.; Proc. R. Soc. London, Ser. A 119, 173 (1928).
[13] Gomer, R. Field emission and Field Ionization (Harvard University Press, Cambridge, 1961), P. 195.
[14] Collins, P. G.; Zettl, “Unique characteristics of cold cathode carbon nanotube matrix field emitters,” A. Phys. Rev. B 55, 9391 (1997).
[15] F. Nava, K. N. Tu, E. Mazzega, M. Michelini, and G. Queirolo, “Electrical transport properties of transition-metal disilicide films”, J. Appl. Phys 61, 1085 (1987).
[16] V. Probst, H. Schaber, A. Mitwalsky, H. Kabza, and B. Hoffmann, “Metal-dopant-compound formation in TiSi2 and TaSi2: Impact on dopant diffusion and contact resistance”, J. Appl. Phys. 70, 693 (1991).
[17] B. M. Ditchek and M. Levinson, “Si-TaSi2 in situ junction eutectic omposite diodes”, Appl. Phys. Lett. 49, 1656 (1986).
[18] M. Levinson, J. Schlafer, and B. M. Ditchek, “Si-TaSi2 composite Photodiodes with Wavelength-Independent Quantum Efficiency”, IEEE Transactions on Electron Devices 38, 2563 (1991).