【作者】 曹雪；

【导师】 舒永春；

【作者基本信息】 南开大学 ， 凝聚态物理， 2012， 博士

【摘要】 本论文“ITO、AZO靶材用纳米粉体的制备与III-V族半导体合金薄膜的生长研究”,在所进行的课题研究上分为两个主要方向：批量分别制备ITO靶材与AZO靶材用的SnO2、In2O3与ZnO纳米粉体和采用固态源分子束外延技术生长三元半导体合金薄膜的热力学研究。论文的主要内容分为透明导电氧化物薄膜及其陶瓷靶材、ITO靶材用纳米粉体的制备及工艺优化、AZO靶材用ZnO纳米粉体的制备及工艺优化、SSMBE生长III-V族半导体合金薄膜的研究四个部分。取得的主要成果和结论如下：1、利用高压反应釜水热法制备出ITO靶材用SnO2纳米粉体。系统研究了在批量（0.5kg/批）制备粉体的条件下，各项工艺参数：反应溶液浓度、前驱体溶液的pH值、水热反应温度、釜内反应最高压力以及水热反应时间等对于SnO2纳米粉体粒径、形貌以及晶型的影响，从而得到优化的制备工艺参数。发现了与文献报道中不同的现象：在保持反应最高压力恒定的情况下，水热反应温度对粒径的影响存在一个转变点（220℃），当反应温度低于220℃时，晶粒度会随着温度升高变大；当反应温度高于220℃时，随着温度升高其晶粒度反而呈现下降的趋势。水热反应时间也存在一个敏感点（12h），当反应时间低于12h时，随着反应时间的增加，SnO2开始成核并逐渐长大，晶粒度随着时间的增加而增大；当反应时间进一步增加到12h后，晶粒度随着时间的延长而变小。2、利用高压反应釜采用水热法对In2O3纳米粉体进行了批量制备工艺的研究，确定了利用水热法制得的中间产物In(OH)3经过高温烧结后得到In2O3纳米粉体的基本工艺。通过调整烧结温度，得到适宜的并能与SnO2粉体相匹配的In2O3纳米粉体，为粉体的进一步烧结以及制备ITO靶材奠定基础。3、采用直接沉淀化学法制备了AZO靶材用ZnO纳米粉体。结合XRD、SEM等粉体表征手段，对采用不同锌盐原料、反应溶液浓度、溶剂中乙醇的含量、煅烧温度等工艺条件对ZnO的粒径、形貌和晶型的影响进行了综合比较研究，并得到优化的制备工艺参数。4、采用固态源分子束外延技术生长III-V族半导体合金薄膜材料，建立了三元化合物的热力学理论模型，将晶格应变能和温度对吸附和脱附的影响这两个参数因子引入模型中，推导出束流、生长温度和组分在MBE生长过程中的相互关系，并根据实验生长数据模拟出所建模型的具体参数值。通过计算拟合得到的理论曲线与实验数据得到较好的吻合。该热力学模型对后续的III-V族半导体薄膜材料的生长具有一定的指导意义。更多还原

【Abstract】 This dissertation is focused on the preparations of ITO and AZO tagetnanopowders and the growth of III-V semiconductor alloy films, which is dividedinto two main directions. One is the preparations of large-scale SnO2and In2O3nanopowders for ITO target materials and ZnO nanopowders for AZO. The other isthe thermodynamic alalysis of ternary semiconductor alloys grown by SSMBE. Thereare four main parts in this work: the summaries of transparent conductive oxide thinfilm target materials; the preparations and process optimizations of ITO nanopowders;the preparations and process optimizations of AZO nanopowders; the study of III-Vsemiconductor alloy compounds grown by SSMBE. In the following, the primaryachievements in this dissertation are described.1. SnO2nanopowders of ITO target materials have been prepared byhydrothermal method with an autoclave. In the case0.5kg/batch production, theeffects of synthesis conditions including concentration of initial solution, pH value ofprecursor solution, reaction temperature, maximum pressure and reaction time ongrain size, particle morphology and crystal structure have been systematically studied.Unlike previous reports, some unusual dependences of the grain size of SnO2onreaction temperature and time have been found. There is a transition point (220℃) inreaction temperature effect on the production grain sizes. When the temperature isbelow220℃,grain sizes become larger with the temperature rising; when it is above220℃, on the opposite, grain sizes become smaller with the temperature rising. Andthere is also a transition point (12h) in reaction time effect. When the time is less than12h, SnO2particles begin to nucleate and grow up with the time rising; when the timeis more than12h, grain sizes become smaller with the time rising opposite.2. The batch preparations of In2O3nanopowders have been studied byhydrothermal method with an autoclave. The results show that the synthetic powdersby hydrothermal method are In(OH)3, and the hydroxides will be transformed intoIn2O3after sintering. By adjusting the sintering temperature, In2O3nanopowders canbe matched with SnO2nanopoeders, which lays the foundation for further sintering of the powder targets.3. ZnO nanopowders of AZO target materials have been prepared by directprecipitation method. The powders are characterized by means of X-ray diffractionand Scanning electron microscopy. The effects of synthesis conditions includingdifferent zinc salts as precursor, concentration of initial solution, solvent mixeddifferent proportions of ethanol and sintering temperature on grain size, particlemorphology and crystal structure have been systematically studied.4. A thermodynamic model for solid source molecular beam epitaxy growth ofternary III-V semiconductor alloys has been established. The energy of lattice strainand the decomposition of group-V element are both incoporated into this model, anda clear relational expression among growth temperature, flux ratio and alloycomposition is derivated. The calculation results are presented as well as comparisonswith existing experimental data. This setup model has some directions for the growthof other III-V semiconductor thin film materials.更多还原