應用無毒性AZO改善CIGS及DSSC太陽能電池效率之研究

Abstract

本研究針對RF射頻磁控濺鍍在常溫下製備AZO透明導電膜，應用田口實驗設計配合灰關聯-田口法，分析AZO透明導電膜結晶性對電阻率、光穿透率的影響。在進行退火處理，因蘇打玻璃具有鹼元素可能會擴散到薄膜內影響薄膜電性，因此在蘇打玻璃與AZO透明導電膜間加入Al2O3緩衝層來防止鹼元素擴散到AZO透明導電膜，實驗結果於添加Al2O3緩衝層後電阻率下降至2.64×10-3 Ω-cm，薄膜光穿透率可維持在84%左右。 AZO透明導電膜應用於染料敏化太陽能電池中電極結構，於AZO透明導電膜間加入二氧化鈦緻密層(TiO2 compact layer)可以防止電子、電洞對在次結合，能有效提升染料敏化太陽能電池之光電轉換效率，使用田口法規劃TiO2 compact layer製程，配合灰關聯尋求TiO2薄膜最佳鍍膜參數(濺鍍功率、基板溫度、氬氧比及製程壓力)，進一步分析TiO2 compact layer對薄膜光觸媒性質與電池轉換效率影響，由實驗結果顯示TiO2 compact layer可以提高染料敏化太陽能電池的短路電流提升電池的光電轉換效率。 最後應用磁控濺鍍系統製備可撓性CIGS薄膜太陽能電池進行研究，於電極層沉積不同製程參數的鉬合金，探討薄膜結構對電極的片電阻值、附著力影響及變化，經計算後最佳電阻率為2.8×10-4Ω-cm，符合做為CIGS薄膜太陽能電池之需求，以直流濺鍍的方式鍍製CIG金屬層前驅物，藉由改變銦靶鍍膜時間來調整Cu/(In+Ga)比產生CIGS吸收層，研究結果發現，當元件經由光電轉換效率量測所得到的轉換效率為:對照組:(η)= 5.13% ；三明治堆疊法: (η)= 8.71%；擴散法: (η)= 7.37%；披覆法: (η)= 6.96%。

AZO thin films were deposited on soda lime glass by RF magnetron sputtering .Taguchi method with a L9 orthogonal array, signal-to-noise (S/N) ratio and analysis of variance (ANOVA) were employed to examine the performance characteristics of the coating operations. The grey-based Taguchi method showed that the electrical resistivity of AZO films is about 3.33×10-3 Ω-cm, and the visible range transmittance is about 87.64 %. Furthermore, by applying a very thin Al2O3 buffer layer with the thickness of 10 nm. The lowest electrical resistivity was 2.64×10-3Ω-cm. A thin TiO2 compact layers which is by means of radio frequency (rf) magnetron sputtering coating ensures higher photo catalytic activity and increased dye-sensitized solar cells (DSSC) conversion efficiency. It can prevent charge recombination and a higher short circuit current density. The experimental results show that the DSSC conversion efficiency is critically affected by the thickness of the compact TiO2 layer. CIGS thin film solar cells are coated on SUS430 which is flexible. CIGS thin film solar cells are coated on MoNa and Mo films back contact which is made form Direct current (DC) magnetron sputtering system. The electrical, adhesion, structural and morphological properties were analyzed that the thickness was fixed at 1000 μm. Above of all, the best conversion efficiency (η) reaches 8.71 %