化学机械抛光技术研究进展

通过回顾化学机械抛光技术的发展历史,概述了化学机械抛光作用机制与实际应用情况,着重阐述了几种重要抛光浆料(如CeO2、SiO2、Al2O3抛光浆料)的优缺点、抛光机理及其国内外新近制备方法,进一步展望了化学机械抛光技术的发展前景与新型抛光浆料的开发方向.     

化学机械抛光液的研究现状

化学机械抛光(CMP)是一种化学腐蚀和机械磨削协同作用的超精密加工技术。化学机械抛光液是化学机械抛光技术中关键的一部分,对材料的全局平坦化处理起到了至关重要的作用。综述了化学机械抛光液中各组分对抛光性能的影响研究。     

化学机械抛光装置

公开号　ＣＮ1251791Ａ　　申请人　日本电气株式会社　　地址　日本东京都　　一种化学一机械抛光装置,包括一个抛光垫、一个抛光台、一个晶片夹具、一个用于在对特定数目的晶片进行化学和机械抛光之后设置抛光垫的修整器;及一个根据抛光速度和所需的抛光时间控制设置抛光垫的条件的条件控制器。化学机械抛光装置可在每次对待定数目的晶片抛光之后适宜的调整抛光垫的设置条件,并能正确的进行后续的抛光。化学机械抛光装置     

化学镀镍工艺的应用

对化学镀镍工艺技术在实际生产中的应用作了详细的论述,介绍了阳极保护技术在维护镀液稳定性、镀后机械抛光及提高镀层装饰上的应用,总结了化学镀镍在实际生产中应注意的操作事项及常见的故障分析和解决方法。     

化学机械抛光中机械作用去除机理的研究

在计算机硬盘技术中,为了满足磁头磁盘的表面粗糙度及波纹度的要求,将化学机械抛光(Chemical Mechanical Polishing,CMP)作为硬盘盘片表面最终精加工手段。CMP是一个复杂的化学机械过程,主要作用为磨粒的机械作用,通过建立一个机械去除模型分析硬盘盘片与抛光垫之间的相对速度、抛光液中的颗粒浓度以及压力三个过程变量对CMP材料去除速率的影响。     

聚氨酯/无纺布复合抛光垫的微结构控制及透水性能改进

化学机械抛光中,抛光垫的材料特性是影响抛光效率和光亮度的重要因素之一。聚氨酯抛光垫通常由聚氨酯和无纺布复合制备而成。具有微结构可调性能的聚氨酯抛光垫由改进后的两步法制得,无纺布浸渍聚氨酯浆料后,部分溶剂在水浴中去除,然后在烘箱中去除剩余溶剂。改进后工艺的预凝聚温度、预凝聚时间、浆料浓度等参数获得了优化,并研究了其对抛光垫结构、性能的影响。改进后的方法使聚氨酯与无纺布纤维紧密结合,既保证了纤维之间孔隙的存在,又增加了材料的强度,在不损失材料硬度的前提下,显著提高了产品的透水性,并有利于打磨效率的提高。与此同时,该方法可以有效减少有机溶剂的使用,大幅缩减生产成本,具有节能、环保的特点。     

半导体工业中的化学机械抛光(CMP)技术

介绍了半导体工业中蓬勃发展的化学机械抛光(CMP)技术.重点叙述了CMP技术所采用的设备及消耗品,CMP过程机理,抛光片的检测及影响抛光片质量的因素,CMP技术的应用及发展趋势.     

电化学测试技术在集成电路制程化学机械抛光中的应用现状

简述了包括开路电位法、极化曲线法、恒电位法、电化学阻抗谱在内的常规电化学测试技术的原理.总结了近几年内这几种电化学测试技术在化学机械抛光领域研究中的应用现状,展望了未来的发展方向.     

聚乙烯醇浆料在织物上浆中的适用情况

通过对聚乙烯醇化学结构与物理化学性能的分析,并与传统浆料的性能进行比较,提出了作为浆料的聚乙烯醇系列产品的工艺性能、品种选择以及所用添加剂使用的范围,并就目前国内外生产的品种提出参考使用的范围。     

PA6/不锈钢热压复合界面性能研究

采用机械抛光、化学刻蚀以及退火分别对304不锈钢表面进行预处理,并利用自制模具将聚酰胺6（PA6）注塑试样与不锈钢进行热压成型。力学性能测试结果表明,经过机械抛光后的不锈钢与PA6热压的搭接强度为3.31 MPa, 而经过抛光、化学腐蚀和退火处理后,复合制件的搭接强度达到17.48 MPa,失效模式由界面失效变为内聚失效;扫描电子显微镜、原子力显微镜观察结果表明,化学刻蚀后的不锈钢表面具有微纳米孔洞,热压时塑料熔体进入金属表面微纳米孔洞形成锚定效果;傅里叶红外光谱分析结果表明,PA6与退火处理后的金属表面氧化物形成了化学键;锚定结构与化学键合有利于提高复合件的力学性能。     

EFFECTS OF NONIONIC SURFACTANTS ON PERFORMANCE OF COPPER CHEMICAL MECHANICAL POLISHING

During copper chemical mechanical polishing (Cu-CMP), the physical properties of slurry, such as the dispersion and suspension stability of abrasives, the interaction between particles and the polished surface, and the rheological characteristics, greatly affect the planarization efficiency. In this study, several nonionic surfactants were added to change the aforementioned physical characteristics of slurry and Cu-CMP performance. Their effects were investigated. The experimental results showed that Al₂O₃ slurry with 300 ppm Triton DF-16 could enhance the wettability of the Cu surface and stabilize the dispersion of abrasives in the slurry. Therefore, the passivation reaction on the Cu surface during CMP would occur uniformly, and the removal of particles during post cleaning could be improved. Cu CMP using the slurry with an adequate amount of nonionic surfactants, Triton DF-16, is proposed to reduce the surface roughness, enhancing the planarity.     

EFFECTS OF NONIONIC SURFACTANTS ON PERFORMANCE OF COPPER CHEMICAL MECHANICAL POLISHING

During copper chemical mechanical polishing (Cu-CMP), the physical properties of slurry, such as the dispersion and suspension stability of abrasives, the interaction between particles and the polished surface, and the rheological characteristics, greatly affect the planarization efficiency. In this study, several nonionic surfactants were added to change the aforementioned physical characteristics of slurry and Cu-CMP performance. Their effects were investigated. The experimental results showed that Al₂O₃ slurry with 300 ppm Triton DF-16 could enhance the wettability of the Cu surface and stabilize the dispersion of abrasives in the slurry. Therefore, the passivation reaction on the Cu surface during CMP would occur uniformly, and the removal of particles during post cleaning could be improved. Cu CMP using the slurry with an adequate amount of nonionic surfactants, Triton DF-16, is proposed to reduce the surface roughness, enhancing the planarity.     

Potassium sorbate as an inhibitor in copper chemical mechanical planarization slurries. Part II: Effects of sorbate on chemical mechanical planarization performance

This study reports on the effects of potassium sorbate (K[CH₃(CH)₄CO₂]) on copper chemical mechanical planarization (CMP) performance and demonstrates how the performance can be controlled by the inhibitor concentration in the slurry. The study is a continuation of a recent report on the copper polishing mechanism in H₂O₂/glycine-based slurries using sorbate as an inhibitor. CMP performance with respect to the inhibitor concentration in the slurry is evaluated in terms of surface roughness, polishing uniformity and dishing values. CMP results obtained from blanket wafers show that an increased sorbate concentration provides lower roughness values. CMP data obtained from patterned wafers shows that an increased sorbate concentration provides better polishing uniformity and lower dishing values for copper lines. The high solubility of sorbate in water (up to 9 M) is a major advantage for CMP processing.     

Potassium sorbate as an inhibitor in copper chemical mechanical planarization slurry. Part I. Elucidating slurry chemistry

The integration of an advanced inhibitor, potassium sorbate (K[CH₃(CH)₄CO₂]), in a copper CMP slurry based on hydrogen peroxide and glycine is reported. The first part of the study discusses the slurry chemistry by qualitatively describing the processes involved and proposes a mechanism for a hydrogen peroxide-glycine based slurry having sorbate anion as an inhibitor. For this purpose, the specific role of each chemical constituent in the slurry was elucidated at a fundamental level by electrochemical studies, X-ray photon spectroscopy (XPS) and contact angle measurements, all linked to the CMP performance on blanket wafers. Once the polishing mechanism was resolved the influence of the inhibitor was evaluated by CMP processing of patterned wafers.     

Effect of hydroxy carboxylates as complexing agent on improving chemical mechanical polishing performance of M-plane sapphire and action mechanism analysis

As sapphire device performance continues to improve, greater challenges are posed to the chemical mechanical polishing (CMP) of sapphire, with its high degree of hardness and brittleness. M-plane sapphire substrates are not widely used because they are more difficult to process, despite having higher luminous efficiency than C-plane substrates. In this study, the effect of three hydroxyl carboxylates, namely potassium tartrate (PT), potassium citrate (Cit) and sodium gluconate (Gluc), as complexing agents on the CMP of M-plane sapphire was investigated to obtain a high material removal rate (MRR) and low root mean square surface roughness (Sq). First, the chemical reactivities of the three complexing agents were predicted with Material Studio (MS) software. The predicted results showed that the complexing ability of the three complexing agents was greatest for Gluc, followed by Cit, with PT having the least complexing ability. Experimental results confirmed that Gluc was the optimal complexing agent for the M-plane sapphire CMP. The mechanism of action during CMP was revealed by X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (FTIR). The results showed that the Al(OH)₄^? ions produced by the sapphire were complexed by Gluc to form the soluble complex Al(OH)₄^?/Gluc^?. At the same time, a solid phase reaction also occurred between the M-plane sapphire, SiO₂, and water during CMP, and Al₂Si₂O₇?2H₂O was generated. After polishing with the optimized slurry, the M-plane MRR was improved to 5.358 μm/h, a 50% improvement compared with the reference slurry, and the Sq decreased from 0.345 nm to 0.172 nm. These findings provide important guidance for the development of high-performance sapphire devices.     

Mechanistic difference between Si-face and C-face polishing of 4H–SiC substrates in aqueous and non-aqueous slurries

The traditional aqueous-based polishing slurries have been extensively used in the ultra-precision machining process of SiC substrates, but their processing efficiency remains a major challenge in making SiC wafers with high surface quality. SiC polishing slurries based on non-aqueous solvents have been explored and reported, however, the mechanism for the accelerated SiC material removal rate (MRR) remains unknown. In this work, the Si-face and C-face of the SiC wafer were polished with water and methanol as polishing liquid carriers, respectively. The MRR of Si-face using the methanol-based slurry, can reach 260.9 nm/h, and the polished Si-face surface roughness Ra reduces to 0.150 nm. In contrast, the MRR of Si-face by using the aqueous-based slurry, is 66.8 nm/h, the polished Si-face surface roughness Ra is 0.691 nm. However, the results of MRR and Ra for C-face are opposite. The reaction between the polishing liquid carriers and the atomic structures of Si-face and C-face lead to differences of the MRRs by analyzing contact angle, XPS, and molecular dynamics (MD) simulation results. The newly revealed polishing mechanisms shined light for speeding up the development of SiC polishing slurries based on the specific aspects of the polishing surface of SiC.     

集成电路铜互连钌阻挡层异质材料去除选择性的研究

针对集成电路铜互连钌阻挡层异质材料(包括Cu、Ru、TEOS)在化学机械抛光(CMP)中选择性差的问题,在SiO2 H2O2体系抛光液中研究了(NH4)2SO4和2,2′{[(甲基1H苯并三唑1基)甲基]亚氨基}双乙醇(TT)对Cu、Ru、TEOS去除速率的影响,并使用钌阻挡层图形片对抛光液的平坦化性能进行验证。结果表明,(NH4)2SO4的添加可以提高Cu、Ru和TEOS的去除速率,进一步加入TT后,Cu的去除速率减小,Ru和TEOS的去除速率基本不变。采用由5%(质量分数,下同)SiO2、0.15%H2O2、40 mmol/L(NH4)2SO4和1 g/L TT组成的抛光液对钌阻挡层图形片化学机械抛光30 s后,碟形坑和蚀坑的深度得到了有效降低。     

Chemical-mechanical polishing of low dielectric constant poly(silsesquioxane): HSQ

In this study, the chemical-mechanical polishing (CMP) characteristics of the low dielectric constant poly(silsesquioxane) (HSQ) were investigated. CMP behavior was studied using different kinds of slurries, additives, and pads. The slurriesused included SiO₂ based slurry (SS-25), ZrO₂ based slurry (A-1), and Al₂O₃ based slurry (WA400). The additives used to change the surface interaction behavior were Triton X-100 and HNO₃. The role of the polishing pad was investigated by a hard pad (IC 1400) and a soft pad (Politex). The experimental results suggested that the hardness of the abrasives and pads and the electrostatic interaction between the abrasive and polymer surface were responsible for the polishing results.     

Electrochemical characterization of Cu dissolution and chemical mechanical polishing in ammonium hydroxide–hydrogen peroxide based slurries

Chemical mechanical polishing (CMP) of copper in ammonium hydroxide based slurry in the presence of hydrogen peroxide was investigated. The polishing trend was found to be similar to that exhibited by other slurries containing hydrogen peroxide and various complexing agents used for Cu CMP. When the hydrogen peroxide concentration is increased, the polish rate increases, reaches a maximum and then decreases. The location and the magnitude of the maximum depend on the ammonium hydroxide concentration. The dissolution of copper in the NH₄OH–hydrogen peroxide solution was probed by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) experiments. Electrical equivalent circuit (EEC) and reaction mechanism analysis (RMA) were employed to determine the mechanistic reaction pathway of Cu dissolution in NH₄OH–hydrogen peroxide system. Based on the RMA analysis, a four step catalytic mechanism with two adsorbed intermediate species is proposed.     

Study on the interaction between SiO2 and ZrO2 in the chemical mechanical polishing of zirconia ceramic with colloidal silica

Colloidal silica is usually used for the chemical mechanical polishing of zirconia ceramic wafer in industry, but the process is often optimized only through experience without a precise understanding of the polishing mechanism. There are still many theoretical and technical issues, especially the material removal mechanism and the effect of polishing on the phase transformation, have not been studied in depth. In this study, the effect of the abrasive concentration, polishing pressure and slurry pH on the material removal rate was analyzed. It is found that the removal rate tends to be stable when the concentration exceeds 30 wt%; the influence of pressure on the polishing rate conforms to the Preston formula. When the pH of the slurry is 6, the removal rate is the highest, but polishing under acidic conditions will leave corrosion pits due to the dissolution of the stabilizer. Through X-ray photoelectron spectroscopy analysis of the residue on the wafer surface, it was found that Si-O-Zr bonds were formed, but it was uncertain whether the residue was zirconium silicate. Through X-ray diffraction analysis, it is found that polishing will not affect the crystal structure of zirconia. The Zr-O-Si bond formed by tribochemical action on the ceramic surface prevents the deep migration of surface hydroxyl groups. At the same time, kinetic factors will cause internal hydroxyl groups to transfer to the surface for recovery oxygen vacancies, thereby stabilizing the tetragonal phase.