【作者】 高倩；

【导师】 韩高荣； 李吉学；

【作者基本信息】 浙江大学 ， 材料学， 2014， 博士

【摘要】 镀膜玻璃是最主要的新型建筑节能玻璃,既可以保持玻璃的透光性,又可以高效阻隔热量的传递,赋予普通平板玻璃特殊的功能,满足节能、环保、安全和装饰等多种需求,按功能可分为阳光控制镀膜玻璃、低辐射镀膜玻璃、自清洁镀膜玻璃等。利用不同氧化物材料各自的物理和化学性能,采用浮法在线化学气相沉积技术,通过对氧化物薄膜微纳结构与性能的调控,以实现节能镀膜玻璃大面积均匀与高性能的兼顾,在建筑节能领域有着广阔的应用前景。同时,开展纳米尺度氧化物薄膜的可控制备,研究制备工艺-结构-性能之间的相互关系,对于这类材料的发展及应用拓宽具有重要的科学意义。本文首先简要概述了建筑节能镀膜玻璃的研究与应用现状,主要针对低辐射镀膜玻璃与自清洁镀膜玻璃,重点总结和评述了以SnO2:F为代表的透明导电薄膜和Ti02薄膜的制备与性能的研究现状,以及该类薄膜具有节能效果的原理。针对氧化物薄膜制备中存在的大面积均匀稳定镀膜困难、多层膜结构匹配与节能优化技术缺乏等问题,提出开展新型节能玻璃的材料膜系设计、多层匹配和微结构调控技术的研究,本文采用浮法在线化学气相沉积技术,在玻璃表面首次制得微纳结构SnO2：F薄膜、纳米镶嵌结构SiCxOy薄膜以及纳米Ti02薄膜。采用多种分析测试技术对三类薄膜的结构、均匀性、稳定性、光学性能、电学性能和亲水性等性能进行了研究。同时系统研究了低辐射镀膜玻璃在温度场作用下结构与性能变化的过程与机理。本文主要研究内容和结果如下：(1)采用浮法在线MOCVD法,以单丁基氯化锡和三氟乙酸作为先驱体,通过反应温度、薄膜前驱体流量等工艺参数调控、退火处理等手段控制晶体成核-生长过程,首次在玻璃基体表面制得了大面积、均匀、金红石相、柱状生长的微纳结构SnO2:F薄膜,即薄膜是由尺寸为5nm-10nm的SnO2晶粒取向聚集成的100nm-300nm颗粒所形成。微纳结构的SnO2:F薄膜通过对载流子的散射作用,有利于薄膜获得更为优异的低辐射性能。通过结构的调控,获得了雾度值达到～10.3%,方块电阻～11Ω·sq-1,辐射率低于0.16,可见光品质因数～10-3数量级,硬度值达到15.08GPa,杨氏模量达到206.93GPa的SnO2:F透明导电薄膜,该类薄膜在低辐射镀膜玻璃与薄膜太阳能电池领域具有很好的应用前景。(2)采用浮法在线常压CVD法,以硅烷、乙烯、CO2作为前驱体,通过控制表面梯度氧化、薄膜沉积的反应温度和时间等参数调节纳米Si成核-生长过程,获得了大面积、均匀的纳米镶嵌SiCxOy薄膜,即由5nm大小的Si晶粒均匀镶嵌在Si-C-O无序网络中形成。这类薄膜被选择作为阻挡层的膜层材料。(3)结合SnO2:F薄膜和SiCxOy薄膜的制备,在浮法生产线上,采用热分解CVD方法在锡槽内镀硅碳氧等多元化合物薄膜,然后采用MOCVD方法在退火窑内镀氧化锡等氧化物薄膜,制备得到了大面积、均匀的SnO2:F/SiCxOy复合镀膜玻璃。采用FIB-TEM手段,观察到了薄膜的三明治结构,其中SnO2:F膜层趋于柱状生长,具有很好的结晶性,SiCxOy阻挡层为多层纳米镶嵌结构,在膜层与膜层之间存在元素组分的过渡层。(4)系统研究了阻挡层对SnO2:F薄膜结构与性能的影响,选择了SiCxOy和SixSnyO2作为阻挡层膜层材料进行研究和对比。具有阻挡层的SnO2:F薄膜具有更为均匀的表面形貌,颗粒分布在～200nm-300nm,且呈现更为明显的金字塔结构。阻挡层的引入弥补SnO2:F膜层与玻璃基体之间由于晶格不匹配而产生的大量孔洞,保证了膜层之间较好的结合力,改善了薄膜的力学性能。在结构上,阻挡层的引入提高了SnO2:F薄膜的结晶性,增强了其在(200)晶面的取向生长。在性能上,由于结构与形貌的改善,且阻挡了玻璃基体中的Na+、K+离子的扩散,具有阻挡层尤其是SiCxOy阻挡层的SnO2:F薄膜具有更为优异的光电学性能,电阻率下降到4.9×10-4,中远红外反射率提高到～85%,辐射率降低到0.16。因此,SiCxOy薄膜为一种理想的运用于FTO薄膜的阻挡层材料。(5)对低辐射镀膜玻璃的稳定性进行了研究,发现当较长时间热处理且温度高于～580℃,将导致薄膜中微米尺寸的多面体颗粒分裂成纳米尺寸小颗粒,同时产生大量的颗粒界面,这些界面的产生使SnO2:F薄膜的霍尔迁移率和方块电阻增大,进而导致薄膜低辐射性能的劣化。定义了一个“H”因子来定量标定SnO2:F薄膜表面形貌的一致程度,并且将其与薄膜的性能联系起来,从而通过表面形貌的变化来考察薄膜的性能。发现低的“H”因子对应于低辐射性能较优异,方块电阻较小,对低辐射镀膜玻璃的工业化生产具有指导意义。(6)模拟了玻璃钢化的过程,研究了原位和非原位钢化过程中SnO2:F低辐射镀膜玻璃结构与性能的变化。当钢化温度达到650℃,钢化时间大于10min,薄膜的方块电阻明显增大、中远红外反射率降低、低辐射性能明显变差。这是由于薄膜在空气中高温处理,氧气的化学吸附和F的向外扩散,导致了薄膜空位的减少,载流子浓度的降低。同时,薄膜内部界面的变化,通过界面散射导致薄膜霍尔迁移率的明显降低。因此,薄膜的载流子浓度和霍尔迁移率发生明显下降,最终导致薄膜光电性能的劣化。为了保证SnO2:F低辐射镀膜玻璃在钢化过程中保持较好的光电性能以及满足国家标准的低辐射率,钢化时间需控制在10min之内。(7)以四异丙醇钛(TTIP)作为先驱体,采用常压MOCVD方法,通过控制镀膜温度、镀膜气体流量和速度,控制晶体成核-生长过程,在玻璃基体表面快速制备出大面积、均匀的TiO2薄膜,该类薄膜为一种锐钛矿相结构纳米薄膜,由尺寸小于10nm的TiO2纳米晶粒组成,表面均匀、致密,粗糙度小于10nm,从光学参数上分析可以分为致密层与表面粗糙层,具有较好的结晶性,晶态含量大于60%。(8)通过调控TTIP浓度和前驱体总流量,系统研究了浮法在线制备参数对TiO2薄膜结构与形貌的影响,优化了锐钛矿相TiO2薄膜的结晶性,获得了表面致密、粗糙度小于5nm的纳米TiO2薄膜。同时,该类薄膜兼具优异的可见光透过率和亲水性,满足自清洁镀膜玻璃对采光和自清洁性能的要求,是一种较为理想的阳光易洁镀膜玻璃。更多还原

【Abstract】 Due to the energy-saving demands in the world, oxide thin films coated glass has been considered as a promising novel energy-saving building material. Different oxide thin films are selected due to function of the coated glass, including excellent transparency in the visible spectrum range and high electrical conductivity or other properties. Energy-saving coated glass can be classified as low-emission coated glass, solar control coated glass, self-cleaning coated glass, etc. Investigation on the controllable preparation of oxide thin films on the glass substrate via APCVD method on the float production line and further building the relationship between the microstructures and properties, are highly desired to develop and expand application for these materials.In this dissertation, the status of energy-saving coated glass, emphatically summarized SnO2:F low-emissivity coated glass and TiO2self-cleaning coated glass, have been reviewed firstly. The structure, preparation and the principle of energy saving effect of such oxide thin films have been summarized. However, the preparation of large area uniform oxide thin films, the matching of multilayer films, the optimization of the functional properties of such energy-saving glass remain a challenge. Thus, new type of energy-saving multilayer films system has been designed, multi-layer matching and microstructure control technology have been investigated. Via float on-line APCVD technology, micro-nano structural SnO2:F thin film, nano-particle reinforced structural SiCxOy thin film and nano TiO2thin film were prepared for the first time in the glass substrate. Moreover, various measurement methods were employed to study the structure, stability, optical properties, electrical properties and hydrophilic performance of such thin films. In particular, the variation of the structure and functional properties of SnO2:F low-emission coated glass under high temperature has been systematically explored. The main contents and results are summarized as follows:(1) The homogeneous SnO2:F thin film with stable microstructural and functional properties was successfully deposited on glass substrate at a large-scale of3-m in width via APCVD method on an industrial production line. It was observed for the first time that the as-deposited SnO2:F thin film presented a micro-nano structure type, of which micro-sized grains (100-300nm) assembled by nano-sized crystallites (<10nm). With the control of the structure and morphlogy, such SnO2:F series film exhibited haze value of-10.3%, sheet resistance of～11Ω·sq-1, emissivity lower than0.16, hardness reached15.08GPa, Yong’s modulus reached206.93GPa, allowing its potential applications as the low-emission coated glass and the front TCO for amorphous and microcrystalline silicon based solar cells.(2) The homogeneous SiCxOy thin film with nano-particle reinforced structure, of which nano-sized Si particles (<5nm) embedded in the amorphous Si-C-0network, was successfully deposited on glass substrate at a large-scale of3-m in width via APCVD method on an industrial production line. This kind of thin film presented a potential application as barrier layer material during the production of low-emission coated glass.(3) SnO2:F/SiCxOy multilayer low-emission coated glass was designed and prepared. Thermal decomposition CVD method is used to deposit SiCxOy layer in the tin bath, and MOCVD technique is chosen to deposit SnO2:F layer in the annealing kiln. Vie FIB-TEM method, the sandwich structure of the low-emission glass was observed for the first time. The SnO2:F thin film showed a uniform nanocrystalline nature of cassiterite structure and the SiCxOy showed amorphous multilayer structure.(4) The effect of barrier layer, SiCxOy and SixSnyO2on the modification of the structure, surface morphology and functional properties of SnO2:F thin film was investigated and compared. An improvement in preferential orientation, the (200) crystallographic orientation in particular, has been confirmed via inserting barrier layers. Furthermore, a homogeneous surface morphology and enhanced columnar growth structure are confirmed for SnO2:F films with barrierlayer.(200) orientation preferred SnO2:F/SiCxOy/Glass films with larger grain size and a columnar growth structure were found to exhibit lower resistivity(～4.9×10-4), higher reflectance in the mid-far-infrared region (～80%) and lower emissivity (～0.16). The SiCxOy barrier layer has presented more positive influence in improving the preferentially orientation, surface morphology and functional property of SnO2:F thin film compared with the SixSnyO2layer, suggesting that the SiCxOy film maybe a more ideal potential barrier layer material during SnO2:F thin film production.(5) The stability of SnO2:F thin film was investigated. It was found that post-heating at～580℃or above for20min induced a splitting phenomenon of the micro-sized polyhedron-like grains into smaller ones. Meanwhile, more grain boundaries emerged led to the decreased Hall mobility and increased sheet resistance. In addition, the low-emission property of the SnO2:F thin film was found to drop dramatically with such heating conditions. A harmonic factor,’H’factor, was defined to quantify the structural influence on the low-emission functional property. The study has thus demonstrated the highest temperature for SnO2:F low-emission glass to maintain the good functional properties, and provided a critical guidance for the further modern energy-saving glass industrial production.(6) The glass tempering process in industry was simulated by in-situ and ex-situ technology to SnO2:F/SiCxOy low-emission coated glass. After tempering process at-650℃with varied periods, the sheet resistance of the SnO2:F thin film remained stable for less than10min, but increased dramatically when the tempering period exceeded10min, which was mainly due to the oxygen chemisorptions and fluorine ion diffusion. The calculated emissivity of the SnO2:F glass tempered for less than10min has reached as low as0.16. The study has therefore suggested the appropriate tempering conditions for the SnO2:F low-emission glass in industrial.(7) A series of TiO2thin films were prepared via atmospheric pressure chemical vapor deposition (APCVD) method on an industrial production line. By adjusting the deposition temperature, total flow rate, concentration of precursor, etc, the process of crystal nucleation and growth was controlled. The as-deposited large-are TiO2thin film presented good crystallinity of anatase structure, crystalline content greater than60%, uniform surface morphology with roughness less than10nm.(8) Via controlling the concentration of TOP and the total flow rate of precursor, the relationship between the microstructure and properties of TiO2thin film was investigated. The increased concentration and total flow rate modified the crystallinity, decreased the surface roughness and improved the hydrophilic property of TiO2thin film, which allowed it being a potential applications as the self-cleaning coated glass.更多还原