溶胶-凝胶旋涂法制备Sn-Al共掺ZnO薄膜及光电性能研究

The Photoelectric Properties of Sn-Al Co-doped ZnO thin films Prepared

By sol-gel Process and Spin-coating

Abstract

Transparent conductive thin films are widely used in liquid crystal displays,transparent electrode solar cells and various photoelectric devices because of their good photoelectric properties.Transparent conductive oxide films are widely used.However,because of its toxic and expensive price,ITO film limits its application.Because of its own advantages,ZnO based films have been studied by researchers,and the purpose of replacing ITO films has been achieved.Zinc Oxide(Zinc oxide,short for short)is a metal oxide with six angle zinite structure.Room temperature with band gap is a direct band gap of3.37eV.ZnO of the exciton binding energy is relatively high(about60meV),stable performance,not easy to react with other substances,has been applied in optoelectronic devices.So it has been a hot topic of excellent synthesis to choose the appropriate preparation method of ZnO thin films.

In this thesis,intrinsic ZnO thin films using ethylene glycol monomethyl ether as the solvent and zinc acetate as the precursor for the system,Al doped ZnO thin films and Sn-Al Co-doped ZnO thin films using nine hydrated aluminum nitrate and crystallization of four tin chloride as the doping agent to provide Al and Sn sources,ethanolamine as preparation of colloidal stabilizer,were successfully prepared on substrate by sol-gel technique adopting spin coating process after heat treatment.Through the study of the preparation conditions of the intrinsic ZnO,the optimum parameters to prepare ZnO thin films were pre-treatment temperature of180℃and the substrate of Si.The lattice parameters,structure and crystal quality,microstructure,photoluminescence and transmission properties were investigated by X-ray diffraction(XRD),scanning electron microscopy(SEM),photoluminescence(PL) spectrum and ultraviolet visible spectrophotometer(UV-vis).The results show that:(1) introducing two elements of Al and Sn into ZnO thin films,without changing the lattice structure of the films,have a certain effect on the preferred orientation of C axis of the films, and the grain size of the films change.(2)Al doped ZnO thin films have better preferred orientation,smaller grain size,wider band gap,smooth surface and more than90% transmittance of the thin films.(3)Sn-Al Co-doped ZnO films.The incorporation of Sn improves the photoelectric properties of the films,and makes the transmittance of the film further improved and the electrical properties are better.

Key Words：Sol-gel method;ZnO Films;Al Doped thin films;Sn-Al Co-doped;The photoelectrical properties

目录

摘要.............................................................................................................................I Abstract......................................................................................................................................II 1绪论.. (1)

1.1引言 (1)

1.2透明导电薄膜的简介 (1)

1.2.1透明导电薄膜的分类 (1)

1.2.2透明导电薄膜的应用 (2)

1.3ZnO基透明导电薄膜 (3)

1.3.1ZnO的性质 (3)

1.3.2ZnO的晶体结构 (3)

1.3.3ZnO的掺杂 (4)

1.3.4ZnO基透明薄膜的应用 (5)

1.4本论文的研究意义和研究内容 (5)

1.4.1课题研究的目的和意义 (5)

1.4.2课题研究的主要内容 (6)

2薄膜的制备方法和表征手段 (7)

2.1薄膜的主要制备方法 (7)

2.1.1脉冲激光沉积法（PLD） (7)

2.1.2化学气相沉积法（CVD） (7)

2.1.3分子束外延法（MBE） (8)

2.1.4磁控溅射法 (8)

2.1.5超声喷雾热解法（USP） (8)

2.1.6溶胶凝胶法（Sol-Gel） (8)

2.1.7其他工艺 (9)

2.2溶胶凝胶工艺的简介 (9)

2.2.1溶胶凝胶的原理 (9)

2.2.2溶胶凝胶法的成膜特点 (9)

2.2.3胶体的制备机理 (10)

2.2.4溶胶凝胶制膜方法 (11)

2.3薄膜的表征手段 (13)

2.3.1X射线衍射仪 (13)

2.3.2扫描电子显微镜 (14)

2.3.3光致发光谱 (15)

2.3.4紫外—可见分光光度计 (16)

2.3.5样品表征使用的仪器 (17)

2.4本章小结 (17)

3溶胶凝胶旋涂法制备ZnO薄膜及工艺分析 (18)

3.1实验药品和实验器材 (18)

3.1.1实验仪器 (18)

3.1.2实验药品 (18)

3.2ZnO薄膜的制备过程 (19)

3.2.1制备方案与流程 (19)

3.2.2基片的清洗 (20)

3.2.3薄膜的制备 (21)

3.2.4薄膜的热处理 (21)

3.3工艺条件的分析 (22)

3.3.1预退火温度对薄膜的影响 (22)

3.3.2不同衬底对薄膜的影响 (24)

3.4本章小结 (25)

4不同Al掺杂浓度对ZnO薄膜性能的影响 (26)

4.1薄膜晶格结构的分析 (26)

4.2薄膜表面形貌的分析 (27)

4.3薄膜光致发光性能的分析 (29)

4.4薄膜光透过性能的分析 (30)

4.5薄膜电学性能的分析 (31)

4.6本章小结 (32)

5不同Sn掺杂浓度对Sn-Al共掺ZnO薄膜性能的影响 (33)

5.1薄膜晶格结构的分析 (33)

5.2薄膜表面形貌的分析 (35)

5.3薄膜光致发光性能的分析 (37)

5.4薄膜光透过性能的分析 (38)

5.5薄膜电学性能的分析 (39)

5.6本章小结 (40)

6结论和展望 (41)

6.1结论 (41)

6.2展望 (41)

参考文献 (42)

攻读硕士学位期间发表学术论文情况 (45)

致谢 (46)