表面電漿子波能在次波長範圍來侷限光的特性目前極受到重視。舉例來說，表面電漿子波發生在金屬奈米粒子的介面上的時候，表面電漿子因為侷限在靠近在非常小的金屬結構中發生共振，所以這就是所謂的局域化表面電漿子共振。由於局域化表面電漿子共振的效應，它可以被用來改善光伏設備的吸收率，並大幅度降低太陽能光伏吸收層的厚度。
本篇論文研究的第一個目的為藉由金屬奈米粒子提昇局域化表面電漿子共振效應來提升散射。先分析以及研究加入基本球型以及圓柱型的金屬奈米粒子結構下在不同結構大小以及不同頻率入射光下的影響，且再進一步提出改良型藉由加入外型獨特的子彈型金屬奈米粒子來產生更多的散射的新結構，透過優化子彈型金屬奈米粒子的形狀、大小、材料，如此一來將可以提高光伏元件的整體吸收效率。我們可以得知子彈型以及球形奈米粒子之間的改善指數會接近穩定，子彈型以及圓柱型形奈米粒子之間的改善指數會降低。藉由數值軟體COMSOL的射頻模組來模擬光學結構以及獲得增加指數和相對優良率以及整體增加指數.
第二點，我們改變奈米粒子間的距離以及奈米粒子的半徑大小以至於奈米粒子間的距離是奈米粒子的半徑的6倍。對於奈米粒子間的距離比較小的時候，在波長700奈米的時候會有較佳的增加指數。對於奈米粒子間的距離比較大的時候，增加指數會變得不穩定。當以沒有添加子彈型奈米粒子的例子當作基準，整體增加指數會有上限值8.35%。
不同於以往的文獻，本篇論文首先在不同波長並改變入射角的時候研究增加指數。當波長小於600奈米的時候，增加指數會變的很不穩定。因為在短波長的時候發生法諾效應，會在散射光以及飛散射光之間產生破壞型干涉。當波長大於600奈米的時候，入射角效應幾乎不會影響增加指數。此外，當以沒有添加子彈型奈米粒子的例子當作基準，入射角為0和30和45以及60度時，整體增加指數會是0.94% 和1.46% 和1.50%以及5.80%。當以沒有添加子彈型奈米粒子的例子當作基準，入射角為0和30和45以及60度時，能帶隙躍遷增加指數會是0.49% 和0.91% 和0.89%以及5.51%。在入射角45度時，當以沒有添加奈米粒子的例子當作基準，TE mode的整體增加指數比TM mode好11.82%。所以在不同入射角時，我們會只分析TE mode.在不同入射角時。

Surface plasmon polariton (SPP) has attracted considerable attention owing to the property to confine light in sub-wavelength. For instance, the surface plasmon polariton takes place on the metal nanoparticles interface. In this system, due to localizing near tiny metal structure, it has been called localized surface plasmon resonance (LSPR). According to the effect of localized surface plasmon resonance, it can be used to improve absorption in photovoltaic equipment, permitting a considerable reduction in the physical thickness of solar photovoltaic absorber layers.
The first purpose of this thesis is to present a new geometry metal nanoparticles structure for increasing scattering by the localized surface plasmon resonance effect. First we analyze basic sphere and cylinder metal nanoparticle in different pitch and at different wavelength. Then we present the new plasmonic structure devices to increase the scattering on metal nanoparticle by adding bullet shape metal nanoparticles. We realize that the relative better rates (bullet nanoparticle and sphere nanoparticle) become stable and relative better rates (bullet nanoparticle and cylinder nanoparticle) decrease when increasing nanoparticle radius. With radio frequency (RF) module solver in COMSOL, the optical structures are simulated and enhancement factor, improving factor, total enhancement factor are extracted.
Second, we change the pitch and bullet nanoparticles radius and make that the pitch is six times of the bullet nanoparticles radius. For the smaller pitch, the enhancement factor is better at 700 nm. For the larger pitch, the enhancement factor becomes unstable. The total enhancement factor has an upper value 8.35 % when using the case without bullet nanoparticles as benchmark.
Different from some prior works, this thesis is the first to study the change of the enhancement factor between different angles of incident (AOI) at different wavelength. When the wavelength is smaller than 600 nm, the enhancement factor becomes unstable between different AOI. Because the fano effect which is the destructive interference between scattered and unscattered light that occurs below resonance would affect at short wavelength. When the wavelength is larger than 600 nm, the influence of AOI effect becomes small. In addition, the total enhancement factor would be 0.94%, 1.46% and 1.50% and 5.80% which AOI are 0, 30, 45 and 60 degree when using the case without bullet nanoparticles as benchmark. And the enhancement over band gap factor would be 0.49%, 0.91% and 0.89% and 5.51% which AOI are 0, 30, 45 and 60 degree when using the case without bullet nanoparticles as benchmark. In the case that AOI is 45 degree, TE mode offers a distinct advantage over TM mode about 11.82 % when using the case without nanoparticles as benchmark. Therefore, we would just analyze TE mode between different AOI.

Abstract 1
摘要 3
Contents 5
List of Tables 8
List of Figures 10
1.1 Backgrounds 15
1.2 Motivations and Dissertation Organizations 17
Chapter 2 Literature Review 20
2.1 The category of light trapping 20
2.2 The different structure of metal nanoparticles 26
2.3 The phenomenon and property of Plasmonic 32
2.4 The category of plasmonic structure 35
2.5 Summary 38
Chapter 3 Fundamental Principles 39
3.1 Drude Model 39
3.2 Surface Plasmon Polaritons at Metal Particles Interface 43
Chapter 4 Simulation Methodologies 49
4.1 Simulation analysis 49
4.2 Solving procedure 49
4.3 Structural parameters 50
4.3.1 Material features 51
4.3.2 Boundary conditions 54
4.4 Optical property calculation 56
4.4.1 Enhancement factor (Fe) 56
4.4.2 Scattering cross-section 57
4.4.3 Improving factor (Fi) 59
4.4.4 Total enhancement factor (Fte) 59
4.4.5 The enhancement over band gap factor (Fteobg) 59
Chapter 5 Results and Discussion 61
5.1 10 nm silicon dioxide on silicon 62
5.2 With metal nanoparticle arrays(R = 50 nm) 64
5.3 With metal nanocylinder arrays(R = 50 nm) 66
5.4 With metal nanobullet arrays(R = 50 nm) 68
5.5 Calculation of enhancement 70
5.6 Gold and silver nanoparticle (AOI = 0 degree & Pitch = 300 nm, Radius = 50 nm) 74
5.7 The comparison of simulation 75
5.8 Effect of pitch (AOI = 0 degree) 76
5.9 Different angle of incident (Pitch = 300 nm) 79
Chapter 6 Conclusions 89
Reference 91
Appendix 94
A.Collected parameters for metal 94
B.The others simulation results 97
C.The mesh of simulation 99

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