中文摘要：

碳化硅和蓝宝石单晶是重要的空间光学材料,也是高亮度发光二极管用的主要衬底材料,实现它们的高质量化学机械抛光（CMP）加工,需要深入理解高化学稳定性衬底材料的超光滑加工过程的材料去除机制,其中一个具有挑战性的问题是力学-化学耦合作用下表面反应层的形成机制.本文评述了反应层形成机理的研究进展和存在的若干问题,包括表面反应层形成的热力学机理和动力学行为、CMP加工模型晶片体系的建立、表面反应层的结构和组成表征、研究结果可比性等,并提出了若干后续研究的突破点,如设计和建立表面结构可控的CMP加工模型晶片体系,并确定表面层形成的化学反应速率来解耦合化学反应过程和扩散过程.本文特别强调了多学科交叉研究方法的重要性,建议密切结合材料的表面结构及缺陷的控制和表征、表界面结构和组成分析、化学反应机理研究以及表面和胶体化学的表界面作用力测量研究.

英文摘要：

Chemical mechanical polishing/planarization（CMP） of wafers is routinely used as the last mechanical process to produce super-smooth or critically planarized surfaces by removing machining-induced surface/subsurface damages and at the same time reduce the surface roughness to the level nanometers or even sub-nanometers without sacrificing the overall flatness. Successful CMP of monocrystalline silicon carbide（SiC） and sapphire substrates—two major substrates besides silicon for fabrication of high-brightness light emission diode（LED） devices, and also two important optical materials for space applications—demands a deeper mechanistic understanding into the CMP material removal process of these two materials. One of crucial challenges is to reveal the mechanism of formation of the chemical reaction layer affected by chemical-mechanical interaction during CMP. This paper critically reviews the current status of relevant progresses, controversies and challenges. First, we reviewed the debate about the thermodynamic behavior of formation of the chemical reaction layer by carefully comparing the original experimental results and arguments by different groups, including numerous studies on the equilibrium of the reactions involved and the stable reaction products. Second, the inconsistencies on the reaction kinetic behavior of formation and removal of the reaction layer, i.e., the temperature dependent materials removal rates in terms of activation energy, were critically compared and re-analyzed by deriving the numerical values of activation energy from the existing literature. Third, the challenge in establishing the model CMP substrate systems was highlightened in order to stress the urgent requirement for a firm foundation without which the results of different labs were difficult to be critically compared. Last, problems of incomplete characterization of the structure and compositions of the reaction layer and substrates as well as the poor cross-lab repeatability of characterization results were di