本研究以自組之3ω法（3-omega Method）設備進行鍺銻碲（Ge2Sb2Te5,GST）相變化合金薄膜熱傳導係數之量測。以此設備先對二氧化矽（SiO2）薄膜進行量以驗證其可靠性，再對GST與摻雜Ce之GST（GST-Ce）進行熱傳導係數之量測，同時也利用自組之即時電性系量測統分析GST試片之交流阻抗（AC Impedance）性質，並搭配等效電路模型模擬分析GST試片中晶粒與晶界對電與熱性質影響之比重。實驗結果顯示結晶態GST之熱傳導係數（約0.8 W/mK）值皆較非晶態高（約0.35 W/mK），Ce摻雜則降低了GST的熱傳導係數。電性質分析顯示GST試片中之晶界為電阻性質變化之主要貢獻者，此由X光繞射分析顯示Ce掺雜導致晶粒細化，原子尺寸之差異亦引發應力場而成為晶粒成長之阻礙，從而造成相變化溫度與活化能之提高而獲得驗證。正切損失（Tangent Loss）特徵峰值對溫度之變化分析顯示Ce摻雜強化了界面極化（Interfacial Polarization）效應，晶界散射係數計算亦顯示GST-Ce中之細化晶粒結構造成較大程度的電子散射，從而降低了熱傳導係數與提高電阻特性。

This study investigates the thin-film thermal conduction properties of Ge2Sb2Te5 (GST) phase-change alloys by utilizing a self-assembly apparatus based on the 3-omaga (3ω) method. First, the thermal conduction of silicon dioxide (SiO2) was measured in order to identify the reliability of experimental tools. The pristine GST and cerium-doped GST (GST-Ce) thin films were then prepared and their thermal conductivities were measured by the 3ω apparatus. The AC impedance properties of these chalcogenide layers were also evaluated by an in-situ electrical measurement system. The data obtained were then implanted in an equivalent circuit model in order to distinguish the characteristics of grain and grain boundary in the electrical and thermal conduction properties of chalcogenide layers. Experimental results indicated that the intrinsic thermal conductivity of amorphous GST (= 0.35 W/mK) was lower than that of crystalline GST (= 0.8 W/mK) and the Ce doping causes the decrease of thermal conductivity in comparison with the GST of the same microstructure. Electrical analysis revealed grain boundary is the major contributor to the resistance property of GST. This was further confirmed by the grain refinement in GST-Ce sample as revealed by x-ray diffraction analysis as well as the increase of phase-change temperature and activation energy of doped GST layer caused by the stress-induced barrier due to the incorporation of alien atoms in the sample. Analysis of characteristic tangent loss peak shift as a function of temperature shows that Ce doping amplifies the interfacial polarization in GST. A calculation of grain-boundary scattering coefficient illustrates the fine grain structure in GST-Ce implies a more severe electron scattering, leading to the decrease of thermal conductivity and increase of electrical resistance property.

摘 要…………………………………………………………………………….......i
Abstract……………………………………………………………………………......ii
誌 謝…………………………………………………………………………….....iii
目 錄……………………………………………………………………………….iv
圖目錄………………………………………………………………………………...vi
表目錄……………………………………………………………………………….viii
第一章 緒 論………………………………………………………………………1
第二章 文獻回顧………………………………………………………………..……3
2-1、微觀熱傳導現象………………………………………………….…………4
2-2、薄膜熱傳導係數量測方法…………………………………………………4
2-2-1、熱擴散法（Thermal Diffusivity Method）…………………………4
2-2-2、熱傳導法（Thermal Conductance Method）…………………………9
2-3、3?蝒k……………………………………………………………….………11
2-3-1、加熱線上的溫度變化（?幅heater）……………………………………11
2-3-2、待測膜與基板間的溫度變化（?幅interface）…………………….……15
2-3-3、薄膜熱傳導係數的推算……………………………………...……16
2-4、界面熱阻抗（Interfacial Thermal Resistance）……………………………..18
2-4-1、聲異理論模式…………………………………………………...…19
2-4-2、散異理論模式…………………………………………………...…20
2-4-3、散射聲異理論模式………………………………………………...21
2-5、交流阻抗分析（AC Impedance Analysis）…………………………………23
2-6、相變化記憶體（Phase-change Memory，PCM）簡介……………………28
2-7、研究動機……………………………………………………………...……31
第三章 實驗方法及步驟……………………………………………………………32
3-1、實驗流程…………………………………………………………..………32
3-2、試片製備…………………………………………...………………………33
3-2-1、電性量測試片…………………………………………...…………33
3-2-2、3?蝒k熱傳導係數量測試片…………………………………….…33
3-3、電性量測與分析……………………………………………………...……35
3-3-1、退火之GST試片電性量測…………………………………...……36
3-3-2、即時升溫電性量測…………………………………………...……36
3-4、薄膜熱傳導係數量測與分析…………………………………………..…37
3-5、X光繞射分析…………………………………………………………..…37
第四章 結果與討論…………………………………………………………..……..39
4.1、Au/Cr薄膜之TCR測定……………………………………………………39
4.2、標準試片建立暨3?蝬q測系統驗證………………………………………40
4-3、XRD結構分析………………………………………..……………………44
4.4、電性分析……………………………………………………………...……46
4.4.1、交流阻抗分析量測退火試片………………………………………46
4.4.2、即時電性分析………………………………………………………50
4.5、熱傳導係數分析…………………………………………...………………61
第五章 結 論…………………………………………………..…………………70
第六章 未來研究與展望……………………………………………………………71
參考文獻……………………………………………………………………………..72

[1] A. Majumdar, “Microscale Heat Conduction in Dielectric Thin Films”, ASME J. Heat Transfer, 115(1993), p.7.
[2] W.J. Parker, R.J. Jenkins, C.P. Butler, and G.L. Abbott, “Flash Method of Determining Thermal Diffusivity, Heat Capacity, and Thermal Conductivity”, J. Appl. Phys., 32(1961), p.1679.
[3] T. Yao, “Thermal Properties of AlAsr/GaAs Superlattices”, Appl. Phys. Lett., 51(1987), p.1798.
[4] I. Hatta, “Thermal Diffusivity Measurement of Thin Films by Means of an AC Calorimetric Method”, Rev. Sci. Instrum., 56(1985), p.1643.
[5] S.B. Lang, “Technique for the Measurement of Thermal Diffusivity based on the Laser Intensity Modulation Method (LIMM),” Ferroelectrics, 93(1989), p.87.
[6] D.G. Cahill, “Thermal Conductivity Measurements from 30K-750K: The 3 Omega Method”, Rev. Sci. Instrum., 61(1990), p.802.
[7] O.W. Käding, H. Shurk, and K.E. Goodson, “Thermal Conduction in Metallized Silicon-Dioxide Layers on Silicon”, Appl. Phys. Lett., 65(1994), p.1629.
[8] B.V. Seleznev, A.A. Blyablin, A.V. Gavrilov, A.M. Popov, N.V. Suetin, A.V. Knadidov, and A.T. Rakhimov, “Thermal Diffusivity Measurements by “Instantaneous Phase Portrai” Method”, Diamond Relat. Mater., 4(1995), p.1360.
[9] G. Chen, C.L. Tien, X. Wu, and J.S. Smith, “Thermal Diffusivity Measurement of GaAs/AlGaAs Thin-Film Structures”, ASME J. Heat Transfer, 116(1994), p.325.
[10] S.L. Wei and L.C. Chen, “Traveling Wave Method for Measurement of Thermal
[11] K.E. Goodson and M.I. Flik, “Heat Transport in Dielectric Thin Films and at Solid-solid Interfaces”, Microscale Thermophys. Eng., 1(1997), p.85.
[12] E. Jansen and E. Obermeier, “Thermal Conductivity Measurements on Thin Films Based on Micromechanical Devices”, J. Micromech. Microeng., 6(1)(1996), p. 118.
[13] D.G. Cahill, “Heat Transport in Dielectric Thin Films and at Solid-solid Interfaces”, Microscale Thermophysical Engineering, 1(1997), p.85.
[14] D.G. Cahill, “Thermometry and Thermal Transport in Micro/nanoscale Solid-state Devices and Structures”, ASME J. Heat Transfer, 124(2002), p.223.
[15] Carslaw, H. S., J. C. Jaeger, Conduction of Heat in Solids, 2nd ed., Oxford University Press , London, pp. 261-262 (1959).
[16] N.O. Birge and S.R. Nagel, “Wide-frequency Specific Heat Spectrometer”, Rev. Sci. Instrum., 58(1987), p.1464.
[17] S.-M. Lee and D.G. Cahill, “Heat Transport in Thin Dielectric Films”, J. Appl. Phys., 81(1996), p.2590.
[18] T. Borca-Tasciuc. A.R. Kumar and G. Chen, “Data Reduction in 3? Method for Thin-film Thermal Conductivity Determination,” Rev. Sci. Instrum., 72(2001), p.2139.
[19] P.E. Phelan, “Application of Diffuse Mismatch Theory to the Prediction of Thermal Boundary Resistance in Thin-Film High-Tc Superconductors,” ASME J. Heat Transfer, 120(1998), p.37.
[20] G. Chen, “Thermal Conductivity and Ballistic-phonon Transport in the Cross-plane Direction of Superlattices,” Phys. Rev. B, 57(1998), p.14958-14973.
[21] E.T. Swartz and R.O. Pohl, “Thermal Boundary Resistance,” Rev. Modern Phys., 61(1989), p.605.
[22] R.S. Prasher and P.E. Phelan, “A Scattering-Mediated Acoustic Mismatch Model for the Prediction of Thermal Boundary Resistance,” ASME J. Heat Transfer, 123(2001), p.105.
[23] I.S. Beloborodov, A.V. Lopatin, F.W. J. Hekking, R. Fazio, and V. M. Vinokur, “Thermal Transport in Granular Metals”, Europhys. Lett., 69(2005), p.435.
[24] A.A. Abrikosov, Fundamentals of the Theory of Metals, North-Holland, Amsterdam, (1988).
[25] Bo Feng, Zhixin Li, and Xing Zhang, “Effect of grain-boundary scattering on the thermal conductivity of nanocrystalline metallic films”, J. Appl. Phys., 42(2009), p.2849.
[26] E. Barsoukov, Impedance Spectroscopy Theory, Experiment, and Applications, 2nd Ed, John Wiley & Sons, New Jersey, (2005).
[27] T. van Dijk and A.J. Burggraaf, “Grain Boundary Effects on Ionic Conductivity in Ceramic GdxZr1-xO2-(x/2) Solid Solutions”, Phys. Stat. Sol. (a), 63(1981), 229.
[28] M.J. Verkerk, B.J. Middlehuis, and A.J. Burggraaf, “Effect of Grain Boundaries on the Conductivity of High-Purity Zirconium Oxide-Yttrium Oxide Ceramics”, Solid State Ionics, 6(1982), 159.
[29] S.R. Ovshinsky, “Reversible Electrical Switching Phenomena in Disordered Structures”, Phys. Rev. Lett., 21(1968), p.1450.
[30] E. Morales-Sa´nchez, E.F. Prokhorov, J. Gonzalez-Hernandez, and A.Mendoza-Galvan, “Structural, Electric and Kinetic Parameters of Ternary Alloys of GeSbTe”, Thin Solid Films, 471(2005), p.243.
[31] N. Yamada, E. Ohno, K. Nishiuchi and N. Akahira, “Rapid-phase Transitions of GeTe-Sb2Te3 Pseudobinary Amorphous Thin Films for an Optical Disk Memory”, J. Appl. Phys., 69(1991), p.2849.
[32] I. Friedrich, V. Weidenhof, W. Njoroge, P. Franz, and M. Wuttig, “Structural Transformations of Ge2Sb2Te5 Films Studied by Electrical Resistance Measurements”, J. Appl. Phys., 87(2000), p.4130.
[33] T. Ohta, M. Uchida, K. Yoshoka, K. Inoue, T. Akiyama, S. Furukawa, K. Kotera, and S. Nakamura, “Million Cycle Overwritable Phase Change Optical Disk Media”, SPIE, 1078(1989), p.27.
[34] H.-K. Lyeo and D.G. Cahill, “Thermal Conductance of Interfaces Between Highly Dissimilar Materials”, Phys. Rev. B, 73(2006), p.144301.
[35] J. P. Reifenberg, D.L. Kencke, and K.E. Goodson, “The Impact of Thermal Boundary Resistance in Phase-Change Memory Devices”, Appl. Phys. Lett., 29(2008), p.1112.
[36] OMEGA®, “Thermocouple Introduction and Theory“, http://www.omega.com/temperature/Z/pdf/z021-032.pdf.
[37] W.C. Shin and R.S. Besser, “Micromachined Thin-Film Gas Flow Sensor for Microchemical Reactors”, J. Micromech. Microeng., 16(2006), p.731.
[38] T. Yamane, N. Nagai, and S. Katayama, “Measurement of thermal conductivity of silicon dioxide thin films using a 3w method”, J. Appl. Phys., 91(2002), p.9772.
[39] J.A. J. Griffin, F.R. Brotzen, and P.J. Loos, “Effect of thickness on the transverse thermal conductivity of thin dielectric films”, J. Appl. Phys., 75(1994), p.3761.
[40] S. Govorkov, W. Ruerman, and M. W. Horn, “A new method for measuring thermal conductivity of thin films”, Rev. Sci. Instrum., 68(1997), p.3828.
[41] B.Y. Tsui, C.C. Yang, and K.L. Fang, Anisotropic thermal conductivity of nanoporous silica film, IEEE Trans. Electron Devices, 51(1)(2004), p. 20.
[42] C. Hu, M. Morgen, P.S. Ho, A. Jain, W.N. Gill, J.L. Plawaky, and P.C. Wayner, Jr., “Thermal Conductivity Study of Porous Low-k Dielectric Materials,” Appl. Phys. Lett., 77(2000), p.145.
[43] Martin von Arx, “Process-dependent Thin-film Thermal Conductivities for Thermal CMOS MEMS,” J. Microelectromech. Sys., 9(2000), p.136.
[44] G..K. Williamson and W.H. Hall, “X-ray Line Broadening from Filed Aluminum and Wolfram”, Acta Metall., 1(1953), p.22.
[45] S. Arrhenius, “Ober die reacktionsgeschwindigkeit bei der inversion von rohrzucker durch sauren”, Z. Physik. Chem., 4(1889), p.226.