Large area CIGS nanotips array (CIGS NTs) are directly demonstrated by using one step ion milling with deice size over 10 cm2. By controlling the ion milling time and Ar+ incident angles, the length of CIGS NTs can be precisely controlled from 120 nm to 320 nm and the orientation can be adjusted from vertical to tilting angle of 15⁰ with density of nanotips over 4.5 × 1013/cm2. Transmission electron microcopy (TEM) results indicate that these nanotips are of single-crystal structure. The optical properties of the large area CIGS nanotips array (CIGS NTs) were measured by UV-NIR spectrometer, indicating that the reflectance of CIGS NTs is < 1 % at incident wavelengths from 300 nm to 1200 nm. Formation mechanism of these CIGS NTs had been discussed in terms of inhomogeneous concentration variation, crystal quality, and sputtering theories. Both light/dark I-V behavior and external quantum efficiency of these CIGS large area CIGS nanotips array (CIGS NTs) were measured. The results implied that with nanostructure the performance of CIGS NTs might be enhanced.

摘要
本研究採用CIGS四元靶材進行物理性濺鍍製備銅銦鎵硒薄膜，再使用離子蝕刻技術直接於銅銦鎵硒薄膜(CIGS thin film)表面製備大面積規則銅銦鎵硒奈米尖錐陣列(CIGS NTs)以增加接觸面面積進而提高光電轉換效率。藉由調整蝕刻時間可以控制銅銦鎵硒奈米尖錐陣列的長度從120 nm到320 nm，另外，控制氬離子入射角進面控制銅銦鎵硒奈米尖錐陣列的夾角從最大90 度(垂直)到15度。所製備之銅銦鎵硒奈米尖錐陣列之密度更可大於4.5 × 1013/cm2。藉由穿透式電子顯微鏡(TEM)的分析可得知此銅銦鎵硒奈米尖錐陣列為單晶結構。由反射光譜可知，銅銦鎵硒奈米尖錐陣列對於紫外光到近紅外光波段的光具有全反射性質，亦即反射率全小於1%。藉由探討銅銦鎵硒奈米尖錐陣列相對於各種製程條件的成長狀況，釐清離子式蝕刻製備奈米結構形成原因。更進一步藉由量測銅銦鎵硒奈米尖錐陣列之亮/暗電流-電壓和外部量子效應之表現以了解此奈米結構之光電轉換效率。

Contents
Abstract I
摘要 II
Acknowledge III
List of figures VI
List of table VIII
List of Acronyms and Abbreviations IX
Chapter 1. Introduction 1
Chapter 2. Experimental procedures 7
Section 1. Fabrication of CIGS solar cells 7
Section 2. Fabrication nanostructures onto CIGS thin films 8
Section 3. Microstructure analysis 8
Section 4. Measurement of solar cell efficiency 9
Section 5. Instrument list 9
Chapter 3. Results and discussion 17
Chapter 4 Conclusions 35
Reference 36

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