面向高性能集成电路用硅晶片的电场辅助燃烧合成SiC粉体的活化机制

In the production of silicon wafers for integrated circuits, the grinding process plays a crucial role in the quality and efficiency of the surface processing of silicon wafers. The high-performance SiC abrasives with uniform particle size and regular shape are the key material in this process. However, due to the commercial interests of high-end manufacturing, there is not any relevant report about its synthetic technology at home and abroad..The purpose of this project is to quickly prepare β-SiC abrasive powder with controllable particle size and morphology by the electric field assisted combustion synthesis technology.Because the Joule heat effect, mass transfer effect and ionization activation effect of the applied electric field can interfere with the combustion synthesis process of Si/C system, and control the particle size and grain shape of the product (SiC). Firstly, the influence of electric field and process parameters on the synthesis process and the evolution of the phase composition, microstructure and crystal morphology of the products will be systematically investigted. Then the mechanism of nucleation and growth for SiC will be summarized. Finally, by optimizing the process parameters, the purity, structure, grain shape and particle size of the β-SiC abrasive powder synthesized by electric field assisted combustion synthesis will be effectively regulated.

在集成电路用硅晶片的生产过程中，研磨/磨削工序对硅晶片的表面加工质量和效率起到至关重要的作用，粒径均匀、形状规则的高性能SiC磨料是该工序中的关键材料。但是，由于涉及高端制造中的商业利益，其合成技术国内外未见报道。.本项目旨在利用电场辅助燃烧合成技术，实现粒度和形貌可调控的β-SiC粉体磨料的快速制备。即利用外加电场的焦耳热效应、传质效应和电离活化作用，实现对Si/C体系燃烧合成SiC的过程干预，从而控制β-SiC粉体的粒径和粒形。项目首先系统研究电场和工艺参数对合成过程的影响规律，以及产物的相组成、显微结构和晶体形貌的演化规律，归纳出反应过程中SiC的形核长大机制。然后通过优化工艺，实现对电场辅助燃烧合成β-SiC磨料粉体的纯度、微观结构、粒形和粒径的有效调控。

为了满足集成电路用硅晶片的生产过程中对高质量SiC磨料的迫切需求，本项目旨在利用电场辅助燃烧合成技术，解决Si-C反应过程中β-SiC合成和长大的关键科学问题，实现粒度和形貌可调控的β-SiC粉体磨料的快速制备。本项目首先研制了电场辅助燃烧合成β-SiC的实验装置，并开发了相应的合成工艺，实现了电场作用下Si/C体系的稳定自蔓延燃烧合成反应，成功合成出了β-SiC产品。随后，利用实验结合分动力学计算的方法，研究了Si-C高温反应的影响规律，揭示了电场辅助燃烧合成Si-C反应的实质是焦耳热效应，获取了完全Si-C反应的高温合成工艺参数为：反应温度为1500℃，保温时间≥1h，原料粒径≤3μm，Si/C=1.06~1.10，原料坯体致密度≥50%。最后，利用循环加热处理工艺，对合成的SiC粉体进行高温粗化处理，有效粗化了SiC晶粒，获得了1~10μm粒径的粉体产品。该项目的研究成果为开发我国集成电路用硅晶片用高性能磨料提供了新的思路和发展方向，有望服务于该领域的产业升级。