低溫化學水浴法沉積硫化鎘薄膜製程之研究

The study of CdS thin film prepared for chemical bath deposition at Low Temperature

林睿騰(Ruei-Teng Lin)

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(2010年)

摘要

摘要
本次研究主要以低溫化學水浴沉積法(CBD)來製成硫化物(Ⅱ—Ⅵ化合物)半導體薄膜沉積在載玻片上，並藉由在不同配方下製程，量測其光電特性，此種製程可以有效改善在製程中產生大量氨水浪費的情形，以及氨水的使用量也較普遍高溫的CBD製程更低，在製程條件上溫度是以50°C為主，並以改變其鍍液反應時間(10-90min)、反應物濃度變化、以及PH值變化(10-10.5)、和不同錯合劑的掺雜以及濃度等各種配方參數變化，使用SEM(掃描式電子顯微鏡)觀察其試片表面形貌，以XRD(X-ray繞射分析儀)分析其晶體結構。CdS薄膜在低PH值時有(111)的擇優取向，為閃鋅礦立方結構(Znic blende Cubic)；在提高鍍液PH值後，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 )，以及使用UV光譜(紫外光-可見光光譜儀)、低溫PL(光激發光光譜儀)量測薄膜光學特性，其光學能隙約為2.2-2.4eV。
選擇製程較佳之配方於製備CIGS太陽能電池，採用FESEM觀察沉積於CIGS吸收層上之緩衝層薄膜表面結構及橫截面，再使用IV量測太陽能電池特性曲線。沉積在銅銦鎵硒(CIGS)吸收層上作為薄膜太陽電池的緩衝層之鍍液配方，在反應30 min時所沉積的薄膜匹覆性最佳且薄膜厚度能控制在60-80 nm間，其太陽能電池元件轉換效率為6.94%。
關鍵詞: 光伏元件、太陽電池、緩衝層、銅銦鎵硒、硫化鎘、IV量測

關鍵字

太陽電池 ； 緩衝層 ； 銅銦鎵硒 ； 硫化鎘

並列摘要

Abstract

The study is focused on sulfide compound prepared by chemical bath deposition. By under different condition, the samples exhibit various properties. Our process have many advantages including low cadimun waste and low processing temperature, compared to traditional CBD process.
Conditions in the manufacturing process the temperature is 50 ° C based , and to change their bath reaction time (10-90min), reactant concentration, as well as changes in PH value (10-10.5) , and the wrong mixture of doping and different concentration of various formulation parameters, using SEM (scanning electron microscope) to observe the surface morphology of the specimen to XRD (X-ray diffraction analyzer) to analyze its crystal structure.
CdS films have a low PH value (111) preferred orientation for the cubic sphalerite structure (Znic blende Cubic); in raising the value of the bath after PH, CdS films (111) preferred orientation orientation to (100), (002), (101) that is converted to wurtzite hexagonal structure (Wurtzite Hexagonal), and the use of UV spectroscopy (UV - visible spectrometer), low temperature PL (photoluminescence spectrometer) to measure the optical properties of thin films, the optical energy gap about 2.2-2.4eV.
Selection process the better formula in the preparation of CIGS solar cells, observed by FESEM CIGS absorbing layer deposited on the buffer layer on the film surface structure and cross-sections, re-use solar cell IV curve measurements. Deposition of copper indium gallium selenium (CIGS) thin film solar cell absorption layer as a buffer layer of bath compositions, in response to 30 min when the cover piece of film deposition and film thickness can be controlled best in the 60-80 nm between The solar cell conversion efficiency of 6.94%.

Keywords: Photovoltaic Devices, Solar Cells, buffer layers,CIGS、CdS、IV measurement

並列關鍵字

Photovoltaic Devices ； Solar Cells ； buffer layers ； CIGS ； CdS

參考文獻

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