化学是ECMP效率的关键

不同于传统的CMP,ECMP的去除速率与下压力无关。由于利用了二价铜离子与铜界面之间的弱键合,ECMP能够用电解抑制剂来进行更有效的去除。电化学机械抛光(ECMP)技术利用电荷来使平坦化变得更容易。外加电压将金属铜氧化,得到它的离子(Cu 和Cu )。然后这些铜离子与电解液中的化学物质发生反应,形成钝化层。抑制剂是ECMP所用电     

ULSI制造中Cu的电化学机械抛光

电化学机械抛光(ECMP)技术可以在低压力下进行,有可能替代化学机械抛光(CMP)技术,满足含易碎、低介电常数材料的小尺寸特征结构的ULSI中Cu的抛光要求。利用自制的抛光液和改装的抛光机对晶圆片和图案晶圆片上的Cu进行电化学机械抛光,研究了抛光电压、抛光台转速、抛光压力和抛光液流量对抛光速率的影响,发现在抛光电压为4.7V、流量为150～200mL/min、抛光台转速为30～40r/min、抛光压力为3.45kPa时能达到较好的抛光速率。考察了抛光电压对图案晶圆片上台阶高度减小效率的影响,发现台阶高度减小效率随抛光电压增大而减小,并且对抛光机理做了初步分析。     

ULSI多层互连中的化学机械抛光工艺

介绍了化学机械抛光(CMP)技术在大规模集成电路多层互连工艺[1]中的重要作用,对CMP过程和CMP的影响因素进行简单分析。总结出CMP技术在多层互联平坦化中的优势,介绍目前常用互连材料中SiO2介质及其金属材料钨和铜的化学机械抛光常用分析机理,并简单介绍了各种互联材料常用的抛光液及抛光液的组分,对抛光液作了简单的对比。针对传统CMP过程存在的问题,分析了皮带式和固定磨料的CMP技术。     

低压力Cu布线CMP速率的研究

采用低介电常数材料(低k介质)作为Cu布线中的介质层,已经成为集成电路技术发展的必然趋势.由于低k介质的低耐压性,加工的机械强度必须降低,这对传统化学机械抛光(CMP)工艺提出了挑战.通过对CMP过程的机理分析,提出了影响低机械强度下Cu布线CMP速率的主要因素,详细分析了CMP过程中磨料体积分数、氧化剂体积分数、FA/O螯合剂体积分数等参数对去除速率的影响.在4.33 kPa的低压下通过实验得出,在磨料体积分数为20%,氧化剂体积分数为3%,FA/O螯合剂体积分数为1.5%时可以获得最佳的去除速率及良好的速率一致性.     

CMP在集成电路非金属材料平坦化中的应用（Ⅰ）

化学机械抛光（CMP）工艺由IBM于1984年引入集成电路制造工业，并首先用在后道工艺的金属间绝缘介质（IMD）的平坦化，然后通过设备和工艺的改进用于钨（W）的平坦化，随后用于浅沟槽隔离（STI）和铜（Cu）的平坦化。化学机械抛光（CMP）为近年来IC制程中成长最快、最受重视的一项技术。其主要原因是由于超大规模集成电路随着线宽不断细小化而产生对平坦化的强烈需求。本文重点介绍CMP在集成电路中的非金属材料的平坦化应用。     

硅晶圆CMP抛光速率影响因素分析

化学机械抛光(CMP)技术是半导体工艺中不可缺少的重要工艺.针对硅晶圆CMP平坦性问题,系统地考察了压力、转速、抛光垫、浆料、温度等因素对硅晶圆平坦化速率的影响,从中找到它们之间的优化参数,减少CMP工艺中的表面划伤、抛光雾、金属离子沾污,清除残余颗粒,保证硅晶圆的平坦化质量.     

基于DOE优化设计抛光工艺参数

适宜的抛光工艺参数对Si片表面平整度TTV、TIR、STIR等参数起到至关重要的作用.介绍了化学机械抛光(CMP)有效实现Si片全局和局部平坦化的方法和设施,指出并说明CMP是一种化学作用和机械作用相结合的技术,给出了其影响因素.利用DOE(design of experiment)实验方法,结合实际生产条件,获得并验证了最优化的生产工艺参数,改善了Si片表面平整度.     

硅晶圆CMP抛光速率影响因素分析

化学机械抛光(CMP)技术是半导体工艺中不可缺少的重要工艺。针对硅晶圆CMP平坦性问题,系统地考察了压力、转速、抛光垫、浆料、温度等因素对硅晶圆平坦化速率的影响,从中找到它们之间的优化参数,减少CMP工艺中的表面划伤、抛光雾、金属离子沾污,清除残余颗粒,保证硅晶圆的平坦化质量。     

化学机械抛光中的硅片夹持技术

目前半导体制造技术已经进入0.1 3μm时代,化学机械抛光(CMP)已经成为IC制造中不可缺少的技术.本文描述了下一代IC对大尺寸硅片(≥300mm)局部和全局平坦化精度的要求,介绍了目前工业发达国家在化学机械抛光加工中硅片夹持技术方面的研究现状,分析了当前硅片夹持技术中存在的问题,并指出了未来大尺寸硅片超精密平坦化加工中夹持与定位技术的发展趋势.     

用于钴互连CMP抛光液的研究进展

当集成电路技术节点进入10 nm及以下，传统的铜(Cu)互连材料面临着阻容(RC)延迟高、电子散射强等问题，钴(Co)作为制程工艺中的新材料，以其更低的电阻率、更高的硬度和更低的平均电子自由程，成为了替代Cu作为互连材料的优选金属。化学机械抛光(CMP)是去除Co布线层多余材料，实现全局平坦化的唯一技术。而抛光液作为CMP工艺中最重要的耗材之一，其性能的好坏直接决定了晶圆的抛光效果和良品率。回顾了近年来钴互连金属材料的各种新型抛光液的国内外研究进展，讨论了不同化学添加剂对Co材料的去除速率、腐蚀抑制和表面质量的影响。同时总结了钴互连CMP抛光液面临的挑战及发展方向。     

Cu Planarization for ULSI Processing by Electrochemical Methods: A Review

The planned introduction of porous, low-k dielectric materials into Si-based semiconductor devices will provide substantial challenges for chemical mechanical planarization. These challenges arise primarily from the mechanical fragility of such dielectrics, which may not withstand the force applied during chemical mechanical planarization. Planarization by Cu electropolishing has many advantages, including its noncontact nature, easy endpoint detection, and minimal introduction of contamination. However, pattern sensitivity may limit application of Cu electropolishing to augmenting, rather than completely replacing, chemical mechanical planarization. Electrochemical mechanical planarization appears to have less pattern dependence, but is still an evolving technology whose potential limitations are still unclear. Alternative electrochemical methods for Cu planarization, including electropolishing and electrochemical mechanical planarization are herein reviewed and discussed.     

基于化学机械动力学的碱性铜抛光液平坦化机理研究

The planarization mechanism of alkaline copper slurry is studied in the chemical mechanical polishing (CMP) process from the perspective of chemical mechanical kinetics.Different from the international dominant acidic copper slurry,the copper slurry used in this research adopted the way of alkaline technology based on complexation. According to the passivation property of copper in alkaline conditions,the protection of copper film at the concave position on a copper pattern wafer surface can be achieved without the corrosion inhibitors such as benzotriazole(BTA),by which the problems caused by BTA can be avoided.Through the experiments and theories research,the chemical mechanical kinetics theory of copper removal in alkaline CMP conditions was proposed. Based on the chemical mechanical kinetics theory,the planarization mechanism of alkaline copper slurry was established. In alkaline CMP conditions,the complexation reaction between chelating agent and copper ions needs to break through the reaction barrier.The kinetic energy at the concave position should be lower than the complexation reaction barrier,which is the key to achieve planarization.     

Flat, cheap, and under control [electrochemical mechanical planarization]

This paper describes Applied Material's wafer polishing technology, called electrochemical mechanical planarization (ECMP). ECMP is the answer to the problems of electropolishing and chemical mechanical planarization (CMP) of the chip-making process: manufacturing faster, more powerful chips without obliterating their vanishing fine and increasingly fragile features. It is designed to remove excess copper from the top of a newly formed layer of wiring on a chip without damaging the fragile insulation material, called a dielectric, beneath it. ECMP combines aspects of two other technologies, chemical mechanical planarization (CMP) and electropolishing.     

ULSI化学机械抛光的研究与展望

随着半导体行业的飞速发展，集成电路特征尺寸的微细化，半导体薄膜表面的高平坦化对器件高性能、低成本、高成品率有着重要的影响。作为唯一能实现全局平坦化方法的化学机械抛光(CMP)，近年来发展迅速，应用广泛。文章综述了化学机械抛光技术的发展现状：包括化学机械抛光设备、抛光液、抛光机理模型及应用研究进展；在此基础上，对CMP下一步发展的方向及其应用前景进行了展望。     

Planarization properties of hydrogen silsesquioxane (HSQ) influence on CMP

Low dielectric constant materials are now required as intermetallic dielectrics to reduce RC delay in advanced technologies. Hydrogen silsesquioxane (HSQ) is a spin-on dielectric with a dielectric constant around 3. Local planarization of HSQ and its impact on the global planarization due to CMP process was studied. Local planarization of HSQ and its impact on the global planarization due to CMP process was studied. When lines and spaces are equal, HSQ shows a good planarization for lines smaller than 20 μm. In this case, the HSQ thickness on metal line is equal to 2500 Å, which is the minimum which can be obtained for this metal thickness and HSQ deposited. For various environments of the metal line HSQ planarizes better for small lines in a dense zone created by an array of lines or plates of metal. For the CMP process the planarization is good for small lines, as for HSQ but in an array of lines only. Plates must be totally prohibited for CMP process. Finally, for an intermetal dielectric including HSQ the goal of CMP is no more a local planarization as for gap fill but a large scale intra-die planarization.     

用于新一代器件的最新STI和金属CMP浆料

现已开发出了用于浅沟道隔离穴STI雪、铜CMP和低k介质的新型材料。90nm以及下一代技术节点的新型器件要求在软接触CMP条件下减少缺陷率,改善片子表面形貌的衰减。获得的新材料展示了在CMP性能和街写特性方面的改进,因此这些材料被认为能够适应未来技术要求。这些材料的关键之处在于大颗粒尺寸的控制,进行平面化和金属抛光的化学控制以及将控制方法用于旋涂玻璃()材料。     

Mechanical processes in chemical-mechanical planarization: Plasticity effects in oxide thin films

The role of plastic behavior of normally brittle oxide films in controlling materials removal mechanisms in chemical-mechanical planarization (CMP) is discussed. Particular attention is given to how material removal mechanisms are sensitive to fundamental changes in surface materials properties. It is suggested that the synergism between chemical and mechanical effects in CMP can be framed in the context of an environmentally sensitive fracture process. The concept of “fracture” in the case of CMP, however it is argued, occurs at the nanometric or ultimately at the atomistic scale. This type of paradigm for chemical-mechanical planarization is developed through an analysis of the different types of materials behavior associated with surface changes where environment and mechanical effects are coupled.     

在铜CMP过程中降低抛光压力与磨料的机械作用

Chemical mechanical planarization(CMP) is a critical process in deep sub-micron integrated circuit manufacturing. This study aims to improve the planarization capability of slurry, while minimizing the mechanical action of the pressure and silica abrasive. Through conducting a series of single-factor experiments, the appropriate pressure and the optimum abrasive concentration for the alkaline slurry were confirmed. However, the reduced mechanical action may bring about a decline of the polishing rate, and further resulting in the decrease of throughput.Therefore, we take an approach to compensating for the loss of mechanical action by optimizing the composition of the slurry to enhance the chemical action in the CMP process. So 0.5 wt% abrasive concentration of alkaline slurry for copper polishing was developed, it can achieve planarization efficiently and obtain a wafer surface with no corrosion defect at a reduced pressure of 1.0 psi. The results presented here will contribute to the development of a “softer gentler polishing” technique in the future.     

用于铜互连CMP工艺的络合剂研究进展

化学机械平坦化(CMP)是实现65 nm及以下技术节点多层铜互连表面全局平坦化的唯一可靠工艺。络合剂为抛光液的主要组分,对材料去除速率、表面完整性起着至关重要的作用。综合分析了不同官能团的络合剂在铜互连CMP工艺中的应用研究现状,探究了不同官能团络合剂的作用机理,分析了络合剂与其他试剂的兼容性,总结了络合剂的发展趋势。     

Study on the Mechanical Properties of CMP Pads

The mechanical properties of chemical–mechanical planarization (CMP) pads are very important to their performance. In this paper, pads are described in terms of their bulk properties and the properties of their asperity layer for applications in copper CMP. In particular, the elastic properties of these layers are studied.