芯片互连层化学机械平坦化过程中材料移除机理研究进展

doi:10.3901/JME.2022.02.147

摘要/Abstract

摘要： 化学机械平坦化（Chemical mechanical planarization，CMP）是芯片制造中的关键技术，用于实现多种结构表面纳米级别的超精细平坦化。互连层金属和芯片结构中的其他材料性质差异较大，其平坦化过程更加依赖于抛光浆料中的化学组分。协同机理适用于描述金属CMP的材料移除过程：抛光浆料中的化学组分对互连层表面进行化学改性，继而在研磨粒子的机械磨削作用下去除。基于此，综述重点介绍了研究研磨粒子微观状态和作用的接触机制和其相关模型的发展；并分别阐述了氧化剂、络合剂和抑制剂等化学组分的作用和金属的反应过程和原理；最后对抛光液组分最新研究进展和发展趋势进行了归纳总结，以期在芯片制造技术发展过程中，对新型浆料的开发提供参考，以满足不同工况条件下所需的材料去除速率，超精细平坦化和超低缺陷的要求。

关键词: 化学机械平坦化, CMP, 抛光液, 接触机制, 协同机理

Abstract: Chemical mechanical planarization, known as CMP, is one of the key technologies in chip manufacturing and is widely used to achieve the ultrafine planarization of a variety of structures on the nanometer scale. The metals in interconnection layer exhibits quite different properties from the materials in other structures in chips, whose planarization relies more on the chemical components in the polishing slurry. The synergistic mechanism depicts the process of material removal in metal CMP:the surface of the interconnection layer is first chemically modified by the chemical components in the slurry, followed by the subsequent mechanical abrasion and then removed away. Based on the mechanism, the review highlights the contact mechanics which studies the microscopic states and functions of the abrasive particles and the developments of related models; elaborates the roles of the chemical components including oxidizers, complexing agents and inhibitors, and the process and principle of their reactions with metals; summarizes the latest progress and tendency of slurry development. It is expected that it could provide insight on the future slurry developed for new process and materials, so as to achieve the desired material removal rate, superfine planarization and ultra-low defects requirements under different situations during the rapid advancement of the semiconductor manufacturing.

Key words: chemical mechanical planarization, CMP, polishing slurry, contact mechanism, synergistic mechanism

中图分类号:

TG175

杭弢, 常鹏飞, 李明. 芯片互连层化学机械平坦化过程中材料移除机理研究进展[J]. 机械工程学报, 2022, 58(2): 147-158.

HANG Tao, CHANG Pengfei, LI Ming. Research Progress of Material Removal Mechanism in Chemical Mechanical Planarization for Metal Interconnection Layer of Chips[J]. Journal of Mechanical Engineering, 2022, 58(2): 147-158.

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