300mm硅片化学机械抛光技术分析

化学机械抛光是单晶硅衬底和集成电路制造中的关键技术之一,然而,传统的化学机械抛光技术还存在一定的缺点或局限性,为了得到更好的硅片平整度和表面洁净度,在300mm硅片的生产中采用了双面化学机械抛光技术.对双面化学机械抛光的优点以及系统变量对抛光速度和抛光质量的影响进行了详细地分析.     

集成电路多层结构中的化学机械抛光技术

化学机械抛光技术（ＣＭＰ）已成功地应用于集成电路多层结构中的介质层和金属层的全局平面化。这是唯一能对亚微米经器件提供全局平面化的技术，对０．３５μｍ及以下的器件工艺是绝对必须的。ＣＭＰ面临的问题主要是难以维持高效的、稳定的、一次通过性的生产运转。     

镶嵌钨的化学机械抛光的研究

研究的是ＵＬＳＩ镶嵌钨ＣＭＰ的选择性，化学与机械作用匹配，桨料的悬浮及存放和后清洗等问题。     

超大规模集成电路制造中硅片化学机械抛光技术分析

目前半导体制造技术已经跨入0.13μm 和300mm时代,化学机械抛光(CMP)技术在ULSI制造中得到了快速发展,已经成为特征尺寸0.35μm以下IC制造不可缺少的技术。CMP是唯一能够实现硅片局部和全局平坦化的方法,但CMP的材料去除机理至今还没有完全理解、CMP系统过程变量和技术等方面的许多问题还没有完全弄清楚。本文着重介绍了化学机械抛光材料去除机理以及影响硅片表面材料去除率和抛光质量的因素。     

300mm硅片化学机械抛光压力控制技术研究

介绍了一种应用于硅片化学机械抛光(CMP)设备的压力控制技术,综合利用在线检测方法和离线检测方法,借助于Matlab数值分析软件分析抛光主轴压力设定值、气缸气压值、传感器示值以及检测仪器测试值之间的关系,并建立了主轴压力闭环控制系统,达到精确控制主轴压力的目的。工艺实验证明,主轴压力闭环控制系统稳定、可靠、精确。     

ULSI制备中二氧化硅等介质化学机械抛光的研究

对 UL SI制备中 Si、 Si O2 等 CMP工艺技术条件 ,尤其是温度对提高全局平面化即平整度、粗糙度 (抛光雾 )进行了深入研究 ,从机理上提出了以化学作用为主的溶除机理 ,确定了低温、快速率、大流量的新的技术方法。     

化学机械抛光设备关键技术研究

化学机械抛光（CMP）技术作为目前唯一可提供在整个晶圆片上全面平坦化的工艺技术,已被越来越广泛地应用到了半导体领域。介绍了CMP技术原理、晶片夹持、抛光台温度控制、抛光垫修整、终点检测、抛光后清洗等技术以及未来对国内CMP设备的展望。     

铜化学机械抛光中的平坦性问题研究

铜的化学机械抛光(Cu-CMP)技术是ULSI多层金属布线结构制备中不可缺少的平坦化工艺.Cu-CMP后硅片表面的蝶形、侵蚀等平坦性缺陷将降低铜线的最终厚度和增大电阻率,从而降低器件性能和可靠性.而且可能进一步影响硅片的面内非均匀性(WIWUN),在多层布线中导致图案转移的不准确.本文介绍了对Cu-CMP平坦性的仿真、模拟和实验研究,并着重分析了碟形、侵蚀和WlWUN与抛光液、线宽和图案密度、抛光速度和载荷等相关参数的关系.     

ULSI铝布线化学机械抛光研究

在分析铝的物理化学特性的基础上,对甚大规模集成电路(ULSI)铝布线化学机械抛光(CMP)机理进行研究,确定采用碱性抛光液。阐述了所选pH值调节剂的特点,探讨了其在化学机械抛光过程中的作用机理,并分析了所选表面活性剂所发挥的提高高低选择比的作用。最后,对所选pH值调节剂和表面活性剂对铝化学机械抛光的影响进行了实验研究。结果表明:pH值在11.0时,去除速率最快,约为390nm/min;表面活性剂的加入对去除速率影响不大,但可以明显改善表面状态,表面粗糙度降至nm级。     

Platinum chemical mechanical polishing (CMP) characteristics for high density ferroelectric memory applications

The key component of ferroelectric random access memory (FeRAM) is a capacitor including a ferroelectric thin film and electrode materials. Platinum is one of the suitable metals which meet requirements such as low resistivity, high thermal stability, and good oxygen resistance. Generally, the ferroelectric and the electrode materials were patterned by a plasma etching process. The application possibility of chemical mechanical polishing (CMP) processes to the patterning of ferroelectric thin film instead of plasma etching was investigated in our previous study for improvement of an angled sidewall which prevents the densification of FeRAM. In this study, the characteristics of platinum CMP for FeRAM applications were also investigated by an approach as bottom electrode materials of ferroelectric material in CMP patterning. The removal rate was increased from 24.81 nm/min by the only alumina slurry (0.0 wt% of H₂O₂ oxidizer) to 113.59 nm/min at 10.0 wt% of H₂O₂ oxidizer. Electrochemical study of platinum and alumina slurry with various concentrations of H₂O₂ was performed in order to investigate the change of the removal rate. The decreased particle size in the alumina slurry with an addition of 10.0 wt% H₂O₂ oxidizer made the improved surface roughness of the platinum thin films. Micro-scratches were observed in all polished samples.     

Experimental investigation on mechanisms of silicon chemical mechanical polishing

In this research, we conducted a series of experiments to investigate the mechanisms of chemical mechanical polishing (CMP) of silicon. Experimental approaches include tribological tests of frictional and lubricating behavior, chemical analysis, and surface characterization. Specifically, the effects of pH in slurry, surface roughness of wafers, and nano-particle size on removal rate were studied. A transmission electron microscope (TEM), a scanning electron microscope (SEM), and x-ray characterization tools were used to study the change of surface structure and chemistry. Experimental results indicate that the removal rate and planarization are dominated by the surface chemistry.     

Design of experiment (DOE) method considering interaction effect of process parameters for optimization of copper chemical mechanical polishing (CMP) process

Chemical mechanical polishing (CMP) has been widely accepted for the metallization of copper interconnection in ultra-large scale integrated circuits (ULSIs) manufacturing. It is important to understand the effect of the process variables such as turntable speed, head speed, down force and back pressure on copper CMP. They are very important parameters that must be carefully formulated to achieve desired the removal rates and non-uniformity. Using a design of experiment (DOE) approach, this study was performed investigating the interaction effect between the various parameters as well as the main effect of the each parameter during copper CMP. A better understanding of the interaction behavior between the various parameters and the effect on removal rate, non-uniformity and ETC (edge to center) is achieved by using the statistical analysis techniques. In the experimental tests, the optimized parameters combination for copper CMP which were derived from the statistical analysis could be found for higher removal rate and lower non-uniformity through the above DOE results.     

光学石英基片CMP表面粗糙度的研究

In order to achieve a high-quality quartz glass substrate and to improve the performance of Ti O2 antireflection coating,chemical mechanical polishing(CMP) method was used.During CMP process,some process parameters including pressure,polishing head speed,platen speed,slurry flow rate,polishing time,and slurry temperature were optimized to obtain lower quartz surface roughness.According to the experiment results,when pressure was 0.75 psi,polishing head speed was 65 rpm,platen speed was 60 rpm,slurry flow rate 150 m L/min,slurry temperature 20°C,and polishing time was 60 s,the material removal rate(MRR) was 56.8 nm/min and the surface roughness(Ra) was 1.93 °(the scanned area was 1010 m2/.These results were suitable for the industrial production requirements.     

Effect of mechanical process parameters on friction behavior and material removal during sapphire chemical mechanical polishing

The effect of mechanical process parameters such as down force and rotation speed on friction behavior and material removal rate (MRR) was investigated during chemical mechanical polishing (CMP) of sapphire substrate. It was found that the increase in both rotation speed and down force can enhance the MRR and friction force almost linearly depends on the down force and rotation speed. The coefficient of friction (COF) decreases with increasing rotation speed under a fixed down force but keeps constant regardless of variation in down force under a fixed rotation speed. Moreover, the relationship between friction force and MRR was obtained. MRR was proportional to friction force with increasing down force whereas converse proportional to that with increasing the rotation speed. In addition, MRR data are fitted to the Preston equation in the sapphire CMP.     

A model for wafer scale variation of removal rate in chemical mechanical polishing based on elastic pad deformation

It is well known that within wafer non-uniformity (WIWNU), due to the variation in material, removal rate (MRR) in the whole wafer plays an important role in determining the quality of a wafer planarized by CMP. Various material removal models also suggest that the MRR is strongly influenced by the interface pressure. In the present work, an analytical expression for pressure distribution at the wafer and pad interface is developed. It is observed that depending on the wafer curvature and polishing conditions, the interface pressure may exhibit significant variation. The analytical model predictions are first verified against finite element method (FEM) simulations. The predicted analytical pressure profiles are then utilized in Preston's equation to estimate the MRR, and these MRR predictions are also compared to experimental observations. The analytical results suggest, that for a specified wafer curvature there exists a certain polishing condition (and vice versa) that will enable holding the WIWNU within a specified tolerance band. The proposed model facilitates the design space exploration for such optimal polishing conditions.     

CMOS工艺中钨的化学机械抛光技术

介绍了深亚微米CMOS集成电路中研制的关键技术———钨化学机械抛光,比较了化学机械抛光技术与传统反应离子回刻法在金属层与层之间的垂直连接中的优缺点,并指出了钨化学机械抛光工艺中尚存的一些问题,最后对该工艺进行了总结与展望。     

Effect of abrasive particle concentration on preliminary chemical mechanical polishing of glass substrate

Effect of abrasive particle concentration on material removal rate (MRR), MRR per particle and the surface quality in the preliminary chemical mechanical polishing (CMP) of rough glass substrate was investigated. Experimental results showed that the MRR increases linearly with the increase of abrasive concentration and reaches to the maximum when the abrasive concentration is 20 wt.%, and then tends to be stable. When the abrasive concentration increases from 2 to 5 wt.%, the MRR per particle increases greatly and reaches a peak. Then the MRR per particle decreases almost linearly with the increase of the abrasive concentration. The root mean squares (RMS) roughness almost decreases with increasing particle concentration. In addition, in situ coefficient of friction (COF) was also conducted during the polishing process and the zeta potentials of abrasive particles in slurry with different solid concentration were also characterized. Results show that COF value is not related to zeta potential but be sensitive to glass surface conditions in terms of rough peaks in preliminary polishing of glass substrate.     

CMP/Post CMP工艺及其设备

对CMP市场、Cu-CMP、低k-CMP、STI-CMP、W-CMP和PostCMP工艺及其设备进行了论述;并介绍了CMP所要求的研磨膏和研磨垫。