层叠式超薄蓝宝石晶片界面反应高效抛光方法研究

Ultra thin sapphire substrates are widely used as LED substrates and mobile phone cover plates. This project innovatively proposes a layer stacked double-side high efficiency polishing method based on interfacial reaction (solid phase reaction and hydration reaction) for ultra thin sapphire substrates, in an effort to address challenges in double sided simultaneous polishing and low material removal rate with ultra thin sapphire substrates: through “sapphire substrate-ceramics substrate-sapphire substrate” layer stacked weighted thickness increase and sapphire single crystal interface reaction rate enhancement to realize double sided polishing for ultra thin sapphire substrates. Through theoretical analysis and experimental studies to reveal interfacial adsorption mechanisms of ultra thin substrate-hydraulic film-substrate, to reveal interfacial reaction mechanisms of sapphire single crystal substrate, to determine conditions for enhancing interfacial reaction of sapphire single crystal substrate, and to establish a high efficiency polishing method based on sapphire single crystal interfacial reaction enhancement. This research project will have profound importance for the development of sapphire processing industry and the expansion of ultra thin substrate applications in mobile cover plate and LED substrate for our country.

蓝宝石超薄晶片将大量应用于LED衬底以及手机面板，针对蓝宝石超薄晶片难以双面同时抛光、抛光去除率低的难题，本项目创新提出一种基于界面反应（固相反应及水合反应）的蓝宝石超薄晶片层叠式高效双面抛光方法：通过“蓝宝石晶片-陶瓷基片-蓝宝石晶片”层叠式当量增厚方式和强化蓝宝石单晶界面反应速率，以实现蓝宝石超薄晶片的双面抛光。通过机械学、材料学、界面物理和界面化学理论分析和实验研究，揭示超薄晶片-水膜-基片之间的的界面吸附机理，揭示蓝宝石单晶的界面反应机制，确定强化蓝宝石单晶界面反应的条件，由此建立起强化蓝宝石单晶界面反应的高效抛光方法。开展本项目的研究对推动我国蓝宝石加工产业的发展，扩大蓝宝石超薄晶片在手机面板和LED衬底中的应用具有重要意义。

蓝宝石单晶（Sapphire, α-Al2O3）具有优异的光学性能、机械性能和化学稳定性，已作为LED衬底材料获得大量应用，但相对高昂的制造成本制约了蓝宝石晶片的应用。目前，超薄蓝宝石晶片是蓝宝石行业发展的重要方向，但蓝宝石晶片加工普遍采用单平面加工的方式，针对单平面加工超薄蓝宝石晶片效率低、碎片率高的问题，本项目提出了一种超薄蓝宝石超精密加工新方法：利用层叠吸附的方式当量增厚蓝宝石晶片，基于强化界面反应的方式提高加工效率，从而实现超薄蓝宝石晶片的高效超精密加工。本项目通过理论分析、加工实验和计算机仿真相结合的方法揭示了蓝宝石界面反应以及层叠吸附机理，制作了基于强化界面反应的磨具及层叠吸附夹具，分析影响界面反应转化率的因素，实现2英寸0.17mm厚度蓝宝石晶片高效低成本双平面加工技术，为超薄蓝宝石高效超精密加工奠定理论基础，提供关键技术支撑。本项目的研究对丰富超薄蓝宝石超精密加工技术、建立拥有自主知识产权的高效超精密超薄蓝宝石晶片加工技术与理论具有重要意义。