CeO_2/SiO_2复合磨粒抛光性能及机制研究

为提高硅片抛光质量与效率,利用均相沉淀法制备CeO2/SiO2复合磨粒,配制绿色环保水基型抛光液对硅片进行化学机械抛光,研究pH值、抛光时间、抛光速度、抛光压力等抛光工艺参数对硅片抛光性能的影响。结果表明:随抛光液pH值增加,材料去除率相应增大;材料去除率在一定时间范围内随抛光时间增加而下降;材料去除量随抛光速度、抛光压力的增加均先增大后减小。推测CeO2/SiO2复合磨粒抛光机制为由于水合作用,在硅片表面形成一层易于磨削的软质层。     

蓝宝石化学机械抛光时磨粒运动轨迹及抛光效果研究

通过化学机械抛光工艺,获得表面平整度和粗糙度优良的蓝宝石晶片,提高蓝宝石键合接触面的表面性能。采用数值分析软件对蓝宝石晶片化学机械抛光过程中磨粒的运动轨迹进行仿真,结果发现,随着晶片转速的上升,磨粒的覆盖区域增大,当晶片转速与抛光盘转速接近于1∶1时,磨粒的抛光区域覆盖整个晶面。采用控制变量实验的方法研究摆臂的运动和抛光盘的转速对抛光效果的影响,并采用AFM对抛光后的蓝宝石晶片表面形貌进行分析。结果表明,抛光盘转速对抛光效果的影响最大,而移动幅度与移动速度的影响较小。通过调整晶片转速,蓝宝石晶片抛光后达到了键合工艺所要求的表面平整度和表面粗糙度要求。     

超细CeO2磨料对硅片的抛光性能研究

用均相沉淀法制备了不同形状和尺寸的CeO2超细粉体，并配制成不同pH值的抛光液对硅片进行化学机械抛光。研究了不同粒径CeO2磨料的抛光效果，结果表明，微米级的CeO2磨料粒径比较大，切削深度比较深，材料的去除是以机械作用为主。随着磨料粒径的减小，切削深度随之减小，材料以塑性流动的方式去除，最终在2μm的范围内得到了微观表面粗糙度Ra=0．120nm的超光滑表面。实验证明，CeO2磨料对硅片具有良好的抛光效果。     

蓝宝石晶片抛光过程运动仿真及实验分析

本文分析了双面抛光机的抛光原理,建立了晶片在抛光过程中运动的数学模型,采用VC语言时双面抛光加工进行运动仿真,分析了不同参数对抛光效果的影响,获得了最合理的抛光运动参数,并且在抛光机上得到了验证.     

抛光垫在蓝宝石衬底化学机械抛光中的应用研究

在分析化学机械抛光中常用抛光垫的材质、性能、表面结构基础上,研究了抛光垫对蓝宝石衬底抛光质量的影响规律:材质硬的抛光垫可提高衬底的平面度;材质软的抛光垫可改善衬底的表面粗糙度;表面开槽的抛光垫可提高抛光效率;表面粗糙的抛光垫可提高抛光效率;对抛光垫进行适当的修整可使抛光垫表面粗糙;用聚氨酯类抛光垫能够使得蓝宝石衬底的抛光面小于0.3nm的表面粗糙度.     

CeO2/SiO2复合磨粒抛光性能及机理研究

为提高硅片抛光质量与效率,利用均相沉淀法制备ＣｅＯ２／ＳｉＯ２ 复合磨粒,配制绿色环保水基型抛光液对硅片进行化学机械抛光,研究ｐＨ值、抛光时间、抛光速度、抛光压力等抛光工艺参数对硅片抛光性能的影响。结果表明：随抛光液ｐＨ值增加,材料去除率相应增大;材料去除率在一定时间范围内随抛光时间增加而下降;材料去除量随抛光速度、抛光压力的增加均先增大后减小。推测ＣｅＯ２／ＳｉＯ２复合磨粒抛光机制为由于水合作用,在硅片表面形成一层易于磨削的软质层。     

纳米CeO2磨料在硅晶片化学机械抛光中的化学作用机制

通过分析化学机械抛光过程中软质层的形成及其作用过程,研究了使用纳米CeO2磨料进行化学机械抛光时化学作用的机制。分析表明,软质层是抛光液与硅晶片反应形成的一层覆盖在基体表面的腐蚀层,其硬度比基材小,厚度在几个纳米左右。软质层的存在一方面增大单个磨料的去除体积,增加材料去除速率;另一方面能减小磨料嵌入硅晶片基体的深度,这对于实现担性磨削,降低抛光表面粗糙度,提高抛光质量,以及改善抛光效果都有着重要的作用。     

纳米CeO2抛光料对硅晶片进行化学机械抛光的研究

通过自制纳米CeO2超细粉体,并配制成抛光液对硅片进行化学机械抛光,研究了纳米CeO2抛光料对硅片的抛光效果,解释了纳米级抛光料的化学机械抛光原理.实验结果表明:由于纳米抛光料粒径小,切削深度小,故材料去除采用塑性流动方式.使用纳米CeO2抛光料最终在1μm的范围内达到了微观表面粗糙度Ra为0.124nm的超光滑表面,满足了产品的要求.     

氧化铝复合磨粒的抛光特性研究

为提高氧化铝磨料分散稳定性,利用接枝聚合对氧化铝粒子进行了表面改性,并研究了改性后氧化铝粒子在数字光盘玻璃基片中的化学机械抛光特性。结果表明,氧化铝复合磨粒的抛光性能与其表面接枝率密切相关。接枝率上升,材料去除速率下降;试验条件下,当接枝率为2.93%时,氧化铝磨粒体现出较高的表面平整性、较低的表面粗糙度及较低的表面损伤。     

Preparation of silane modified SiO2 abrasive particles and their Chemical Mechanical Polishing (CMP) performances

Surface modified SiO₂ particles in an aqueous environment with γ-aminopropyl triethoxysilane (APTS)/methyl trimethoxysilane (MTMOS) are introduced as abrasive in the slurry. The modified silica particles are characterized by Particle Size/Zeta Potential Analysis, Fourier Transform Infrared Spectroscopy (FTIR), Thermal Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). In addition, the enhancement of polishing rate owning to the modified silicon particles in silicon wafer Chemical Mechanical Polishing (CMP) is observed.     

表面活性剂含量对氧化铈/氧化硅复合磨料分散性的影响

以乙醇为溶剂及表面活性剂,以氨水为催化剂,利用正硅酸乙酯的水解得到氧化硅颗粒,并分析乙醇质量92%时制备的氧化硅颗粒呈球形,粒径分布均匀,表面光滑,呈单分散状态;乙醇质量分数为96%时制备的氧化硅颗粒粒径分布范围大,并且小颗粒团聚一体,聚集到大颗粒上.基于理想的氧化硅颗粒,利用化学沉淀法制备CeO2/SiO2复合磨料,并通过透射电子显微镜(TEM)及X射线衍射仪(XRD)对制备的样品进行表征.结果表明,制备的CeO 2/SiO2复合磨料为球形,粒径为150分数对制备的氧化硅颗粒以及氧化铈/氧化硅复合磨料分散性的影响.结果表明:水解体系中乙醇质量分数为71%时制备的氧化硅颗粒基本呈球形,粒径分布范围大,呈少量单分散状态;乙醇质量分数为~250 n m ,具有草莓状核壳的包覆结构,作为抛光磨料可以提高抛光表面质量.     

纳米SiO2粒子抛光液的制备及其抛光性能

随着计算机磁头与磁盘间间隙的不断减小，硬盘表面要求超光滑，制备了一种纳米SiO2抛光液，并研究了镍磷敷镀的硬盘基片在其中的抛光性能，Chapman MP2000^ 表面形貌仪测得抛光后表面的平均粗糙度（Rα)和波纹度（Wα)分别为0.052nm及0.063nm，为迄今报道的硬盘抛光的的最低值。原子力显微镜（AFM）发现获得的基片表面非常光滑平整，表面无划痕，凹坑，点蚀等表面缺陷。     

Characterization and mechanical/tribological properties of nano Au-TiO2 composite thin films prepared by a sol-gel process

Nano Au-TiO₂ composite thin films on Si(1 0 0) and glass substrates were successfully prepared with a facile sol-gel process followed by sintering. The morphology and mircostructure of the films were investigated via X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and scanning electron microscopy (SEM). The Au particles, of diameter 14-22 nm depending on the sintering temperatures used, were found to be well dispersed in the TiO₂ matrix, with a small amount of the particles escaped from the film. The surfaces of the films were uniform, compact and crack-free. Hardness and elastic modulus of the films were measured by using the nanoindentation technique. Friction and wear properties were investigated by using a one-way reciprocating tribometer. It was found that the highest hardness and elastic modulus values were obtained for the films prepared with 500 °C sintering temperature. The films displayed superior antiwear and friction reduction performances in sliding against an AISI 52100 steel ball. With 5.0 mol% Au, the friction coefficient was only 0.09-0.10 and the wear life was more than 2000 sliding cycles. The friction coefficient and wear life decreased with increasing sliding speed and load. The failure mechanism of the Au-TiO₂ films was identified to be light scuffing and abrasion. Those films can be potentially applied as ultra-thin lubricating coatings.     

液相沉积法制备磁性纳米Fe3O4/SiO2复合粒子

采用液相沉积法在磁性Fe3O4纳米粒子的表面包覆了一层SiO2膜,制备磁性较强的纳米Fe3O4／SiO2复合粒子,采用IR、XPS、XRD、TEM、VSM等方法对复合粒子的性能进行了表征。结果表明：复合粒子的较佳制备条件为正硅酸乙酯(TEOS)的浓度为0．6mol／L,Fe3O4与TEOS物质的数量比为5：1,反应温度为50℃,搅拌速度为800r／min;在此条件下制得的复合粒子的粒径在20nm左右,比饱和磁化强度为60．5emu／g,呈球形且分散均匀。     

Preparation of La-doped colloidal SiO2 composite abrasives and their chemical mechanical polishing behavior on sapphire substrates

Chemical mechanical polishing (CMP) has become a widely accepted global planarization technology. Abrasive is one of the key elements in CMP process. In order to enhance removal rate and improve surface quality of sapphire substrate, a series of novel La-doped colloidal SiO₂ composite abrasives were prepared by seed-induced growth method. The CMP performance of the La-doped colloidal SiO₂ composite abrasives on sapphire substrate were investigated using UNIPOL-1502 polishing equipment. The analyses on the surface of polished sapphire substrate indicate that slurries containing the La-doped colloidal SiO₂ composite abrasives achieve lower surface roughness, higher material removal rate than that of pure colloidal SiO₂ abrasive under the same testing conditions. Furthermore, the acting mechanism of the La-doped colloidal silica in sapphire CMP was investigated. X-ray photoelectron spectroscopy analysis shows that solid-state chemical reactions between La-doped colloidal SiO₂ abrasive and sapphire surface occur during CMP process, which can promote the chemical effect in CMP and lead to the improvement of material removal rate.     

The friction and wear properties of nanometre SiO2 filled polyetheretherketone

Nanometre SiO₂ filled-polyetheretherketone (PEEK) composite blocks with different filler proportions were prepared by compression moulding. Their friction and wear properties were investigated on a block-on-ring machine by running a plain carbon steel (AISI 1045 steel) ring against the composite block. The morphologies of the wear traces and the transfer film were observed by scanning electron microscopy (SEM). It was found that nanometre SiO₂ filled-PEEK exhibited considerably lower friction coefficient and wear rate in comparison with pure PEEK. The lowest wear rate was obtained with the composite containing 7.5 wt.% SiO₂. The SEM pictures of the wear traces indicated that with the frictional couple of carbon steel ring/composite block (fillec with 7.5 wt.% filler), a thin, uniform, and tenacious transfer film was formed on the ring surface. It was inferred that the transfer film contributed largely to the decreased friction coefficient and wear rate of the filled PEEK composites.     

MgO/SiO2复合纳米添加剂的自修复性能试验研究

以纳米MgO/SiO2作为添加剂,在HQ-1摩擦磨损实验机上进行自修复实验。试验考察载荷、转速、修复时间对纳米MgO/SiO2复合添加剂自修复性能的影响。实验结果表明,纳米MgO/SiO2在适宜的条件下对钢-钢摩擦副磨损金属表面有修复效果,其修复性能受载荷、转速及修复时间等条件影响;纳米MgO/SiO2添加剂对磨痕具有一定的填平作用,在一定程度上能够改善磨痕的粗糙度。     

Ekonol/G/MoS2/PEEK复合材料的制备和正交试验研究

用正交试验设计方法和模压方法制备了Ekonol／G／MoS2／PEEK复合材料,通过方差和极差分析方法对材料的耐磨性能进行了研究,并用扫描电镜对磨损表面形貌进行了观察和分析。结果表明,用模压法制备此复合材料是可行的,复合材料具有优良的耐磨性能,其最优制备方案为A5B3C3D3E3;正交试验设计方法、方差和极差分析方法是行之有效的复合材料研究方法。     

高能超声下原位合成ZrB2/A356复合材料及其磨损性能

以Al-K2ZrF6-KBF4为反应体系,在高能超声下原位合成了ZrB2/A356复合材料;研究了超声功率对ZrB2颗粒尺寸、形貌、分布的影响,以及复合材料室温干滑动磨损性能。结果表明:随着超声功率的增加,复合材料中的ZrB2颗粒逐渐细化,其含量也有一定程度提高;当超声功率达到1.6kW时,出现大量ZrB2纳米颗粒,其形貌由原来的块状、柱状变为粒状,复合材料的磨损量减小到56mg,耐磨性提高到1.08,磨损面出现较明显的犁沟。