铟镓锌氧化物（IGZO）靶材烧结行为的原位测量与致密化机理研究

Regarding the problem of the IGZO target material in atmospheric pressure sintering is difficult to achieve ultrahigh density (relative density > 99.5%), we will have an situ measurement on the sintering densification behavior of IGZO target in atmospheric pressure by improving the existed optical dilatometer. We will attempt to find the key factors that influence IGZO densification through a series of tests and analyses which include powder properties (particle size and specific surface area, phase, packing density, etc.), forming and dewaxing art (cold isostatic pressing, slip casting, forming agent content and removal rate, etc.), green compact parameters (relative density, pore distribution and compositional distribution, etc.), sintering atmosphere (oxygen content, atmosphere, gas velocity, etc.), sintering process (temperature, time, ramp speed, two-step sintering, etc.) and their effects on target densification rate, final Sintered density, physical and mechanical properties, pore distribution and microstructure, etc. As data accumulates and bases on the existed densification theories and models, we will deduce a more effective IGZO target densification model by combining power properties, process art, sintering driving force, kinetics and defect chemistry, and check this model through half industrial sintering.

针对IGZO靶材常压烧结难以达到超高密度（相对密度>99.5%理论密度）的问题，本研究拟通过改进现有影像式烧结仪，原位测量IGZO靶材在常压下的烧结致密化行为；探讨粉体性能（粒度、比表面、物相、装填密度等）、成形和脱蜡工艺（冷等静压、注浆、成形剂含量与脱除速度等）、素坯性能（相对密度、孔隙分布，成分分布等）、烧结气氛（氧含量、气氛流速、气氛切换时间等）和烧结工艺（温度、时间、升降温速度、两步烧结等）等因素对IGZO靶材致密化速率、最终烧结体密度、物理、力学性能、孔隙分布和组织结构等的影响，发现影响IGZO致密化的关键因素；然后结合现有通用的致密化理论和模型，从烧结驱动力、烧结动力学和缺陷化学等方面对IGZO靶材致密化机理进行全方位的探讨，阐明IGZO靶材的烧结致密化机理；在此基础上建立一个比较可靠的IGZO烧结致密化模型，为工业上常压烧结制备超高密度IGZO靶材提供理论指导和工艺参考。

铟镓锌氧化物（IGZO）是一种重要的光电功能材料。本项目该项目针对IGZO靶材常压烧结难以达到超高密度（相对密度>99.5%理论密度）的问题，首先对IGZO的原材料粉末进行了系统的研究，制备出了高烧结活性的原材料；同时在基金的支持下建立了一套功能强大的高温原位测量系统，并用该系统原位测量了自制粉末和商业粉末压坯的烧结过程。采用控制烧结曲线理论研究了烧结过程的致密化动力学。研究发现自制粉末较市场粉末具有更高的烧结密度和更低的烧结温度；在粒径相当的情况下，分步沉淀或机械混合粉末较共沉淀粉末具有更低的烧结活化能；控制烧结曲线理论可以完美预测IGZO的烧结致密化过程。本研究为IGZO粉末原料制备和烧结工艺参数制定提供了科学依据，并且可以推广应用到其它同类氧化物半导体材料粉体制备和烧结领域。