用于蓝宝石材料加工的新型超精密抛光技术及复合抛光技术研究进展

超精密抛光是一种降低表面粗糙度,获得高表面质量和表面完整性的加工技术。蓝宝石作为典型的难加工硬脆材料,传统抛光方法存在表面会产生崩碎、划痕等损伤,表面质量难以得到保证以及加工效率低等问题。本文综述了应用于蓝宝石材料的磁流变抛光、水合抛光、化学机械抛光和激光抛光等技术的原理与特点及其研究现状,并分析了各抛光技术的优缺点;从表面质量、磨料与磨液、效率与成本等方面对各抛光技术进行比较;介绍了复合抛光技术在蓝宝石材料中的应用;最后重点展望了蓝宝石材料超精密抛光技术的下一步研究。     

用于蓝宝石材料加工的新型超精密抛光技术及复合抛光技术研究进展

超精密抛光是一种降低表面粗糙度,获得高表面质量和表面完整性的加工技术.蓝宝石作为典型的难加工硬脆材料,传统抛光方法存在表面会产生崩碎、划痕等损伤,表面质量难以得到保证以及加工效率低等问题.本文综述了应用于蓝宝石材料的磁流变抛光、水合抛光、化学机械抛光和激光抛光等技术的原理与特点及其研究现状,并分析了各抛光技术的优缺点;从表面质量、磨料与磨液、效率与成本等方面对各抛光技术进行比较;介绍了复合抛光技术在蓝宝石材料中的应用;最后重点展望了蓝宝石材料超精密抛光技术的下一步研究.     

中国聚氨酯工业现状及未来发展展望

随着国际化、全球化程度的加深和中国这一全球最大聚氯酯市场的进一步显现，众多的国际聚氯酯企业集团在我国实现本土化的进程加快，同时国内企业也开始迈出国门，未来五年我国聚氯酯工业仍处于快速增长期，聚氯酯产品消费量年均增长率将保持在15％左右。     

二氧化铈抛光材料应用的研究进展简

光电子与信息产业的迅猛发展加速了化学机械抛光技术（CMP）的更新。CMP作为目前最好的实现全局平面化的工艺技术（整体平面化的表面精加工技术）,借助超微粒子的切削作用以及材料的化学腐蚀作用可以将硅基材料抛光成光洁平坦表面,已广泛应用在硅基材料、光学元件和电子集成电路等元件的表面平坦化处理。随着抛光精度的逐渐提高,CMP已成为首选抛光技术。为了获得超高精度表面,对抛光材料的调配与生产的要求也不断提高,二氧化铈（CeO2）作为高效的抛光材料,在高精度抛光中得到广泛应用。     

话说稀土抛光材料

<正>1先说"抛光材料"1.1抛光材料为何物抛光材料通常是指用于玻璃抛光的结晶状粉末物质[1]。主要用于对物体表面的处理,如对工件的表面进行抛光,使其更加光滑细润。常见的抛光材料有金属氧化物类,如铝(图1)、锡、铁、锆等氧化物;以及一些无机化合物类,如陶土、白垩、硅藻土等;还有如碳酸盐、金刚石(图2)、碳化硅(图3)等;再有就是金属、塑料抛光材料等。     

金属材料表面的电子束抛光研究进展

电子束技术应用于金属材料表面的抛光,作为一种新型的材料加工工艺,具有抛光效率高、材料去除效果好、抛光表面性能优良等优点。本文在探讨电子束抛光(EBP)技术机理的基础上,介绍了国内外EBP技术所使用的材料和设备类型,给出了EBP技术的数值模型,分析了工件材料、脉冲电压、能量密度和脉冲次数等不同的因素对EBP的影响规律。在总结EBP技术的优点和缺点的基础上,对EBP金属材料的现状和发展方向进行了评价和展望。     

纳米金刚石用作磁头抛光材料的研究

研究了油基金刚石悬浮液用作磁头抛光材料的抛光性能,用原子力显微镜和扫描电子显微镜观察了磁头抛光后的表面。结果表明,纳米金刚石是一种理想的抛光材料,用于超高精度表面加工,其表面抛光质量要明显优于单用国外同类金刚石悬浮液抛光磁头的质量,纳米颗粒的作用十分明显,证实了纳米材料可用超精抛光材料。     

精细雾化抛光氮化硅陶瓷的抛光液配制参数优化

采用超声精细雾化施液抛光对氮化硅陶瓷基体进行抛光,研究了不同的pH值、磨料浓度以及氧化剂含量对氮化硅陶瓷基体抛光的材料去除率的影响,优化了pH值、磨料浓度及氧化剂含量,并与传统的化学机械抛光进行了对比。结果表明:当二氧化硅磨粒质量分数为5wt%,氧化剂含量为1wt%,pH值为8时,材料去除率MRR为108.24nm/min且表面粗糙度Ra为3.39nm。在相同的抛光参数下,传统化学机械抛光的材料去除率MRR为125nm/min,表面粗糙度Ra为2.13nm;精细雾化抛光的材料去除率及表面粗糙度与传统抛光接近,但精细雾化抛光所用抛光液用量仅为传统抛光所用抛光液用量的1/9。     

光学元件聚氨酯抛光特性研究

本文研究了应用于平面光学元件的快速抛光技术,从材料去除率、元件面形和表面粗糙度出发,对快速抛光技术应用于平面大口径元件的加工效果进行了探讨。研究了在快速抛光技术中压力和主轴转速对材料去除率的影响,验证了Preston公式在快速抛光中的适用性,快速抛光技术的去除效率可达10μm/h;其次,研究了聚氨酯抛光元件面形的精度,对于330mm&#215;330mm元件可达～1.0λ（λ=632.8nm）;最后,对快速抛光系统中抛光粉颗粒大小及形态随使用时间的变化进行了观测,并测量了使用300目和500目抛光粉时快速抛光元件表面粗糙度以及其随抛光粉使用时间的变化。     

工业纯铁金相样品制备中形成的缺陷及消除方法

所有材料 ,在磨制与抛光过程中都会产生变形损伤层 ,因材料的软硬、磨光及抛光的程度不同 ,其变形层的深浅也不同。若变形损伤层 ,在抛光阶段未被消除 ,或又产生了新的变形损伤层 ,经侵蚀后 ,组织就会出现假象 ,特别是当材料硬度较低时 ,此种情况较为突出。工业纯铁的退火组织 ,主要是铁素体 ,铁素体的硬度只有 80 HB左右 ,所以抛光过程中 ,稍有不慎 ,就会产生扰乱缺陷 ,影响侵蚀后组织的正确判断。基于此 ,本人将纯铁在抛光及侵蚀过程中易出现的一些缺陷及消除方法作一介绍。(1 )黑白晶粒缺陷。该缺陷是由样品抛光面与抛光布接触处存在局…     

Silica based polishing of {100} and {111} single crystal diamond

Diamond is one of the hardest and most difficult to polish materials. In this paper, the polishing of {111} and {100} single crystal diamond surfaces by standard chemical mechanical polishing, as used in the silicon industry, is demonstrated. A Logitech Tribo Chemical Mechanical Polishing system with Logitech SF1 Syton and a polyurethane/polyester polishing pad was used. A reduction in roughness from 0.92 to 0.23 nm root mean square and 0.31 to 0.09 nm rms for {100} and {111} samples respectively was observed.     

A theory of pad conditioning for chemical-mechanical polishing

Statistical models are presented to describe the evolution of the surface roughness of polishing pads during the pad-conditioning process in chemical-mechanical polishing. The models describe the evolution of the surface-height probability-density function of solid pads during fixed height or fixed cut-rate conditioning. An integral equation is derived for the effect of conditioning on a foamed pad in terms of a model for a solid pad. The models that combine wear and conditioning are then discussed for both solid and foamed pads. Models include the dependence of the surface roughness on the shape and density of the cutting tips used in the conditioner and on other operating parameters. Good agreement is found between the model, Monte Carlo simulations and with experimental data.     

Investigation of pad staining and its effect on removal rate in copper chemical mechanical planarization

In copper chemical mechanical planarization process, stains are often generated on the pad surface due to the build-up of polishing by-products. Pad staining is a major concern because it might affect defect, non-uniformity across the wafer, and removal rate variation during polishing. In this study, the characteristics of stains formed on an IC1000 XY grooved pad obtained under various polishing conditions were investigated. In addition, wafers were polished on an IC1000 plain pad to determine the effect of hydrodynamic pressure on staining pattern. Experiments were performed on a table-top axisymmetric polishing system consisting of a 300-mm non-rotating platen and 100-mm rotating wafers. Stains were successfully generated on the pad surface and X-ray photoelectron spectroscopy (XPS) analysis confirmed that the stains contained copper polishing by-products. As the stains deposited on the pad land areas were darker in the direction of wafer rotation as well as in the pad radial direction, it was believed that staining agents were produced during polishing and subsequently advected downstream by the slurry flow. Although staining increased with polishing pressure, wafer rotation rate, polishing time and slurry flow rate, it did not seem to affect removal rate. The white light interferometric analysis indicated that the stains did not physically change the pad surface topography. It was observed that the hydrodynamic pressure significantly impacted the staining pattern on an IC1000 plain pad.     

Surface Removal Rate in Chemical-Mechanical Polishing

Variation of the surface removal rate with down pressure, pad asperity, and relative velocity in chemical-mechanical polishing (CMP) was studied. A phenomenological model for contact of pad asperities with abrasive particles and wafer is described. The functional dependence of the polishing rate on pressure and velocity was found to be related to the distribution of pad asperities. Simple argument based on the mechanical contact theory suggests that the linear variation predicted by Preston's equation follows when the pad asperities have a random distribution. The sublinear dependence of the removal rate, however, is obtained when the pad asperities have a wavy distribution. The use of the statistical least-square method is suggested as a way to determine the relationship between the removal rate and pressure for different industrial pads used in CMP processes.

CMP polishing planarization surface removal     

Mathematical modeling of polish-rate decay in chemical-mechanical polishing

A model is presented for polish-rate decay in chemical-mechanical polishing based on the Greenwood-Williamson theory of contact between a smooth surface (a wafer) and a rough surface (the polishing pad). The model assumes that polishing causes pad asperities to wear, with high asperities wearing faster than low asperities. Model predictions of the time dependence of polish-rate decay compare favorably with experiments.     

Improved geometry of double-sided polished parallel wafers prepared for direct wafer bonding

Optical technological applications have upgraded polishing, including flat-surface polishing, to an extremely high level of geometrical precision. We deal with the application of this type of precision technology for the preparation of, e.g., silicon or fused-silica wafers that are thin compared to their diameter. To this end a standard optical polishing process using a double-sided polishing machine was modified by giving the polishing pad holder an adaptable curvature. By carefully choosing the process conditions 10-cm-diameter silicon and fused-silica wafers (500-μm thickness) were obtained with a very small deviation from parallelism in the 0.01-μm range. The level of smoothness, surface and subsurface damage, was identical with that required for integrated-circuit processing.     

Pad flattening ratio, coefficient of friction and removal rate analysis during silicon dioxide chemical mechanical planarization

Pad flattening ratio (PFR) was investigated as a non-destructive pad surface analysis method on the IC1000 K-groove pad during silicon dioxide chemical mechanical planarization. The PFR defines as the ratio of the bright area to the total image area. A series of marathon polishing runs were performed under ex-situ diamond disc pad conditioning, ex-situ high-pressure micro jet (HPMJ) pad conditioning and no pad conditioning methods where PFR analysis was performed to estimate the amount of pad surface flattening or glazing under these conditions. With no conditioning, PFR increased rapidly to 40% indicating severe glazing. With ex-situ diamond disc pad conditioning, PFR remained relatively constant below 12%, suggesting a rough and stable pad surface for polishing, while with ex-situ HPMJ conditioning it increased gradually and stabilized at the value of about 23%. Real-time analysis of friction force and silicon dioxide removal rate showed a clear correlation among the PFR, the coefficient of friction and the removal rate during the silicon dioxide chemical mechanical planarization.     

微孔聚氨酯弹性体材料水解稳定性研究

采用相同分子量的聚醚、聚酯和聚醚酯二元醇为原料分别制备密度为0．55g／cm3左右的微孔聚氨酯弹性体（MPUE）材料。并通过一系列测试对这三种微孔聚氨酯弹性体材料进行分析对比。结果发现聚醚型微孔聚氨酯弹性体材料的耐水解性能非常优异,聚酯型微孔聚氨酯弹性体材料的力学性能最好,聚醚酯型微孔聚氨酯弹性体材料的力学性能与聚酯型的力学性能接近,耐水解性能远优于聚酯型,近似于聚醚型。     

微孔聚氨酯弹性体鞋底材料反应体系的研究

介绍了微孔聚氨酯弹性体某地底材料的合成原理,反应体系和发展动态,着重分析了主要原料：异氰酸酯、聚多元醇、扩链剂、发泡剂、催化剂、匀泡剂的种类及用量对聚氨酯鞋底物理机械性能的影响。     

Effect of slurry composition on the chemical mechanical polishing of thin diamond films

Nanocrystalline diamond (NCD) thin films grown by chemical vapour deposition have an intrinsic surface roughness, which hinders the development and performance of the films’ various applications. Traditional methods of diamond polishing are not effective on NCD thin films. Films either shatter due to the combination of wafer bow and high mechanical pressures or produce uneven surfaces, which has led to the adaptation of the chemical mechanical polishing (CMP) technique for NCD films. This process is poorly understood and in need of optimisation. To compare the effect of slurry composition and pH upon polishing rates, a series of NCD thin films have been polished for three hours using a Logitech Ltd. Tribo CMP System in conjunction with a polyester/polyurethane polishing cloth and six different slurries. The reduction in surface roughness was measured hourly using an atomic force microscope. The final surface chemistry was examined using X-ray photoelectron spectroscopy and a scanning electron microscope. It was found that of all the various properties of the slurries, including pH and composition, the particle size was the determining factor for the polishing rate. The smaller particles polishing at a greater rate than the larger ones.