近年來，面對能源的日益枯竭，發展太陽能電池研究的比重增多，為了使得生產成本降低且效率提高，於是，我們致力於利用低溫製程中的鋁誘發結晶製程(Aluminum induced crystallization, AIC)發展多晶矽薄膜沉積於異質基板上來製作太陽能電池的種晶層(Seed layer)，未來也可以使用於建築外牆上。然而，雖然鋁誘發結晶製程可製備出的大晶粒的多晶矽薄膜(>10μm)，但整體過程的反應時間太長(>5Hr)，為了改善鋁誘發結晶製程的反應速率，在這篇論文中我們將1%Si摻雜於初始鋁層中，以加快反應速率，成功在400℃下，退火6分鐘製備出連續的多晶矽薄膜，為了瞭解摻雜矽於初始鋁層對鋁誘發結晶過程中鋁矽交互作用的影響，整個研究以一系列不同退火氣氛、退火溫度、退火時間當作分辨率，分成三個主軸:1)觀察未退火α-Si/Al2O3/Al+1%Si/glass結構的氧化鋁層是否變薄，使得非晶矽層的矽原子更容易擴散到鋁層，加速反應速率；2)探討摻雜法對多晶矽薄膜品質影響；3)探討摻雜1%Si於初始鋁層對多晶矽薄膜結晶性、晶粒大小、結晶方向及成核點影響，進而推測摻雜法如何改變鋁誘發結晶製程的機制。
由實驗結果我們得知，摻雜1%Si於初始鋁層中，在退火的過程中，過飽和的矽會預先在鋁層析出增加矽的成核點，加快反應速率，但與純鋁系統相比，以摻雜法經由鋁誘發結晶製程所製出的多晶矽薄膜晶格方向不再以(100)為主，不利於後續磊晶過程，且薄膜缺陷較多，晶粒較小，使得太陽能電池效率降低，未來希望利用後製程堆疊的方式，幫助效率提高。
在未來研究方向，我們設計將Al+Si層插入α-Si/Al2O3/Al /glass堆疊結構的Al /glass介面，形成α-Si/Al2O3/Al /Al+Si/glass堆疊結構，且此Al+Si層的矽含量不可以超過矽在鋁的飽和溶解度，在退火過程中不會增加成核點，即不會減少(100)結晶方向且晶粒尺寸較不會變小，雙晶密度也不會大幅增加，但可在氧化鋁及鋁層介面處成核後，幫助矽晶粒的成長，達到加速反應速率的效果。

Grow of thin-film polycrystalline Si (pc-Si) as a seed layer has been shown to be useful for further epitaxially thickening absorber layers for thin film solar cell. In order to effectively reduce the cost of seed layer, we propose in this thesis to deposit pc-Si via AIC process on a cheaper foreign substrate such as ceramics or glass which has better mechanical strength. The solar cell fabricated with this proposed process can be potentially used as bricks in the wall of building in the future.
Efficiency of pc-Si thin film solar cell is strongly dependent of grain size and amount of intragraunalr defect. The grain boundary and intragraunlar defects offer electron-hole recombination sites which lead to degrade the efficiency of thin film pc-Si based solar cell. Thus, defect-free large-grain pc-Si film appears to favor solar cell efficiency.
The poly-Si can be grown on a heterogeneous substrate from amorphous Si via aluminum induced crystallization (AIC) method with intermediary metals such as aluminum (Al) at low temperature. For increasing the reaction rate of AIC, in this work, we dope 1% Si into Al layer during AIC process. The effect of aluminum oxide thickness on AIC process, defect density in thin film, crystallinity and nucleation sites of Si grains in the Al layer are carefully studied using high resolution TEM/ EDX. We further discuss the mechanism of Si dopant in initial aluminum layer.
Si dopant in Al layer act as nucleation source in the AIC process, which offers rich nucleation sites to accelerate the reaction rate and reduce the annealing temperature. However, enhanced nucleation process suppresses the grain growth resulting in reduction of grain size. Furthermore, the twin density in poly-Si grains in the grown film with 1%Si doped process is higher than that via a undoped process. Furthermore, preferred orientation of Si grains is not {100} as in the case of undoped process.

[ 1 ]
IMEC, Solar Cells Technology Group, Advances in OptoElectronics, 2007
[ 2 ]
V. M. Fthenakis and P. D. Moskowitz, Progress in Photovoltaics 8, 1, 27-38, 2000
[ 3 ]
B. A. Andersson, Progress in Photovoltaics 81, 61-76,2000.
[ 4 ]
K. Yamamoto, M. Yoshimi, Y. Tawada, Y. Okamoto, A. Nakajima and S. Igari, Applied Physics a-Materials Science & Processing, 69, 2, 179-185, 1999
[ 5 ]
J. Yang, A. Banerjee and S. Guha, Appl. Phys. Lett., 70 , 22, 2975-2977, 1997
[ 6 ]
M.A. Green, Sol. Energy 74, 181, 2003
[ 7 ]
W. Fuhs, S. Gall, B. Rau, M. Schmidt, J. Schneider, Sol. Energy 77, 961, 2004
[ 8 ]
A. L. Fripp, “Dependence of resistivity on the doping level of polycrystalline silicon”, J. Appl. Phys., 46, 1240-1244, 1975
[ 9 ]
S. Y. Yoon, N. Young, P. J. van der Zaag, and D. McCulloch,“High-Performance Poly-Si TFTs Made by Ni-Mediated Crystallization Through Low-Shot Laser Annealing”, IEEE Electron Device Lett., 24, 22-24, 200.
[10 ]
R. B. Bergmann, Applied Physics a-Materials Science & Processing 69 , 2, 187-194, 1999
[ 11 ]
D. Fischer, S. Dubail, J. A. Selvan, N. P. Vaucher, R. Platz, C. Hof, U. Kroll, et al., IEEE Photovoltaic Specialists, 13–17, 1053, 1996
[ 12 ]
S. Reber and W. Wettling, Applied Physics a-Materials Science & Processing 69 , 2, 215-220, 1999
[ 13 ]
R.B. Bergmann, G. Oswald, M. Albrecht and V. Gross, Solar Energy Mater. Solar Cells 46, 147-155 ,1997
[ 14 ]
R. S. Sposili and J. S. Im, Appl. Phys. Lett., 69, 2864, 1996
[ 15 ]
R. Petinot, F. Plais, D. Mencaraglia, P. Legagneux, C. Reita, O. Huet, J. Non-Cryst. Solids, 227–230, 1207, 1998
[ 16 ]
K. Ishikawa, M. Ozawa, C.-H. Oh, and M. Matsumura, J. Appl. Phys, 37, 731, 1998
[ 17 ]
O. Nast, T. Puzzer, L.M. Koschier, A.B. Sproul, S.R. Wenham, Appl. Phys, 73, 3214-3216, 1998
[ 18 ]
S.R. Herd, P. Chaudhari, M. H. Brodsky, J Non-Cryst Solid, 7,309 ,1972
[ 19 ]
K. N. Tu, Appl. Phys. 21, 221, 1975
[ 20 ]
L. Hultman, A. Robertsson, H. T. G. Hentzell, I. Engstrom and P. A. Psaras, J. Appl. Phy 62, 9, 3647-3655, 1987
[ 21 ]
O. Nast, S. Brehme, D. H. Neuhaus, S. R. Wenham, IEEE Transactions on Electron Devices 46, 10, 2062-2068, 1999
[ 22 ]
M. S. Haque, H. A. Naseem, and W. D. Brown, J. Appl. Phys. 79, 7529,1996
[ 23 ]
S. Y. Yoon, K. H. Kim, C. O. Kim, J. Y. Oh, and J. Jang, J. Appl. Phys. 82,5865, 1997
[ 24 ]
S-I. Muramatsu, Y. Minagawa, F. Oka, T. Sasaki, and Y. Yazawa, Sol. Energy Mater. Sol. Cells 74, 275, 2002
[ 25 ]
C. Hayzelden and J. L. Batstone, “Silicide Formation and Silicide-Mediated Crystallization of Nickel Implanted Amorphous Silicon Thin Films,” J. Appl. Phys., 73, 12, 8279–8289, 1993
[ 26 ]
M. S. Haque, H. A. Naseem, W. D. Brown, J. Appl. Phys. 75, 3928 ,1994
[ 27 ]
B. Rau, I. Sieber, J. Schneider, M. Muske, M. Stőger-Pollach, P. Schattschneider, S. Gall, W. Fuhs, J. Cryst. Growth 270, 396, 2004
[ 28 ]
E. Pihan, A. Focsa, A. Slaoui, and C. Maurice, Thin Solid Films, 15, 511–512, 2006
[ 29 ]
S. Gall, J. Schneider, J. Klein, K. Hubener, M. Muske, B. Rau, E. Conrad,I. Sieber, K. Petter, K. Lips, M. Stoger-Pollach, P. Schattschneider, W.Fuhs, Thin Solid Films, 7, 511–512, 2006
[ 30 ]
W. Fuhs, S. Gall, B. Rau, M. Schmidt, J. Schneider, Sol. Energy 77, 961, 2004
[ 31 ]
F. W. DelRio, J. Lai, N. Ferralis, T. J. K. Liu and R. Maboudian, Electrochemical and Solid State Letters 10, 11, H337-H339 , 2007.
[ 32 ]
O. Nast, A.J. Hartmann, J. Appl. Phys. 88 (2000) 716.
[ 33 ]
J. Schneider, J. Klein, M. Muske, S. Gall and W. Fuhs, Applied Physics Letters 87, 3, 2005
[ 34 ]
Jef Poortmans, Vladimir Arkhipov, Thin Film Solar Cells
[ 35 ]
Spinella, S. Lombardo, F. Priolo, J. Appl. Phys. 84, 5383, 1993
[ 36 ]
J. Nelson, The Physics of Solar Cell, 2003
[ 37 ]
Andrey Sarikov, Jens Schneider, Juliane Berghold, Martin Muske, Ina Sieber, Stefan Gall, Walther Fuhs, J. Appl. Phys. 107, 114318, 2010
[ 38 ]
D. Van Gestel, P. Dogan, I. Gordon, H. Bender, K. Y. Lee, G. Beaucarne, S. Gall and J. Poortmans, Materials Science and Engineering B-Advanced Functional Solid-State Materials 159-60, 134-137, 2009
[ 39 ]
F. Liu, M. J. Romero, K. M. Jones, A. G. Norman, M. M. Al-Jassim, D. Inns and A. G. Aberle, Thin Solid Films 516 ,18, 6409-6412, 2008
[ 40 ]
H. Shuman, C. F. Chang and A. P. Somlyo, Ultramicorsc., 19, 121, 1986
[ 41 ]
F. Hofer and P. Warbichler, Ultramucrosc., 63, 21, 1996
[ 42 ]
N. Bonnet, C. Coliex, C. Mory and M. Tence, Scanning Microscopy 2, 351 , 1988
[ 43 ]
A. Berger, J. Mayer and H. Kohl, Ultramicrosc., 55, 101, 1994
[ 44 ]
P. A. Crozier and R. F. Egerton, Ultramicrosc., 27, 9,1988
[ 45 ]
D. B. Williams and C. B. Carter, “Transmission Electron Microscopy”, Plenum Press. New York & London, 1996)
[ 46 ]
A.J .Schwartz, M. Kumar, and B.L. Adams, Electron Backscatter Diffraction in Materials Science, Kluwer Academic , New York, 2000
[ 47 ]
Gall, S., Muske, M., Sieber, I., Nast, O. & Fuhs, W. Aluminum-induced crystallization of amorphous silicon. J. Non-Cryst. Solids 299, 741-745, 2002
[ 48 ]
R MEYER, J PILLOT, B ANDRIES - POWDER MET, 561-581,1971
[ 49 ]
P. S. Chung, “Time Resolved TEM Study of Defects Annihilation in Poly-Si film grown by Aluminum Induced Crystallization Process “, 2011
[ 50 ]
Andrey Sarikov , Jens Schneider , Martin Muske, Ina Sieber, Stefan Gall, Thin Solid Films 515, 7465–7468, 2007
[ 51 ]
S. Gall, M. Muske, I. Sieber, O. Nast, W. Fuhs, J. Non-Cryst. Solids 741, 299–302, 2002
[ 52 ]
J.O. McCaldin, H. Sankur, Appl. Phys. Lett. 19, 524,1971
[ 53 ]
Schneider, A. Schneider, A. Sarikov 1, J. Klein, M. Muske, S. Gall, W. Fuhs, Journal of Non-Crystalline Solids 352, 972–97, 2006
[ 54 ]
R. E. Reed-Hill, ‘Physical Metallurgy Principles’, 3rd ed, 1992