以CBD法沉積硫化鎘及硫化鋅緩衝層研究及其在銅銦鎵硒薄膜太陽電池之應用

The CBD of CdS/ZnS buffer layers for the applications of CIGS thin film solar cells

何政樺(Cheng-Hua Ho)

指導教授 ： 楊立中

國立虎尾科技大學/工程學院/材料科學與綠色能源工程研究所/碩士(2008年)

摘要

本次研究以化學水浴沉積法(CBD)來製成硫化物(Ⅱ—Ⅵ化合物)半導體薄膜沉積在載玻片、ITO玻璃及CIS(Cu-poor、Cu-rich)基板上，並藉著在不同參數沉積下量測其光電特性。
　　硫化物薄膜的沉積製程條件中，通常改變PH值、溶液溫度(65-75 °C)、錯化劑濃度、反應時間(5-40 min)和反應物濃度(Ⅱ族金屬鹽類及硫尿) 。然後將沉積後薄膜經過退火300、400、500°C持溫半小時，利用FE-SEM量測出表面的結構與膜厚，紫外光(UV)光譜儀量測光的穿透率，XRD量測晶體結構來進一步分析其結果。從實驗中發現製程參數的改變呈現出不同的表面形貌。而CdS薄膜在未退火前有(111)的擇優取向，為閃鋅礦立方結構(Znic Blende)；經過退火後CdS薄膜的(111) 擇優方位取向轉為(100)、(002)、(101) 即轉成纖維鋅礦六角結構(Wurtzite Hexagonal )，且薄膜的透光率隨之上昇，能隙也隨之減低，結晶性變佳。不過在退火500°C光的透光率下降，是由於RTA腔體內的氧吸附在CdS晶界上所導致。根據實驗結果得知在反應40 min沉積的薄膜匹覆性最佳且厚度能控制在50-60 nm間，並將此項最佳參數沉積在銅銦硒(CIS)吸收層上作為薄膜太陽電池的緩衝層，從中發現CdS薄膜在不同成分銅銦硒吸收層(Cu-poor、Cu-rich)，有不同的沉積速率以及不同的表面形貌。

關鍵字

硫化鎘 ； 硫化鋅 ； 緩衝層 ； 銅銦鎵硒 ； 化學水浴沈積

並列摘要

The research fabricated sulfide (Ⅱ-Ⅵ compound) semiconductor thin film on SLG、ITO glasses and CIS (Cu-rich、Cu-poor) substrates by chemical bath deposition(CBD), and measure its optic-electronic properties via different deposition parameters.
We usually changes PH meter、solution temperature (65-75°C)、complex agents concentration(Ⅱ-group metal sulphate and thioure) in the conditions of sulfide thin film deposition process. Then annealed 300、400 and 500°C in half hours. Measuring surface morphology figures and film thicknesses by FE-SEM, transmittances by spectroscopy (UV-VIS) and crystal structures by XRD. In the experiment, changing deposition parameters display different surface morphologies. The Zinc Blende structure has (111) preferred orientation without annealing, whereas the (111) turn into (100)、(002) and (101), structure becomes Wurtzite Hexagonal. The transmittance and crystallinity has been quality transformed, and lowing its band-gap. Due to oxygen in the RTA adsorbed at CdS grain boundaries that caused transmittance decreased in 500°C annealing. As experiment, the reacting time (40mins) of deposition can obtain best coverage and the thickness be able to controlled between 50-60nm. The best deposited parameters can be the buffer layer of CIS thin film solar cell. We can see the CdS thin film on different contents of CIS have the different deposition rate and surface morphology.

並列關鍵字

CdS ； ZnS ； Buffer later ； CIGS ； CBD

參考文獻

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