光电化学机械抛光装置设计

针对第三代半导体材料氮化镓(GaN)光电化学机械抛光的加工需求,研制了具有紫外光照射、电压加载和机械抛光功能的光电化学机械抛光(PECMP)装置。设计了紫外光可直接照射到GaN晶片表面的抛光盘单元,加工区稳定加载电压且与装置绝缘的电气回路,抛光盘和工件盘能够独立回转的驱动机构,并且抛光盘可以往复移动、抛光压力可以可调加载。建立了PECMP装置的整机三维模型,通过静力学分析和模态分析,优化了抛光盘和龙门等关键部件结构。搭建了PECMP抛光装置,并进行了性能测试,实现了可施加的光照强度0~200 mW·cm^(−2),电压大小0~10±0.1 V,绝缘电阻150 MΩ,抛光盘转速10~100 r/min,工件转速10~200 r/min,抛光盘往复移动速度1~100 mm/s,压力加载范围0~200 N,满足2英寸GaN晶片的PECMP加工需求。

NiNb_2O_6光电极的还原和表面处理

研究了铌酸镍（ＮｉＮｂ２Ｏ６）半导体电极的还原条件及在光电化学太阳电池中光电解水制取氢时的表面特性。对单晶和多晶压片电极表面逐点研究后表明，其光电化学性质是不均匀的。探讨了机械抛光、化学抛光和光抛光等不同表面处理方法对电极特性的影响。

光学加工及设备

TQ172.684 96021373 浮法抛光亚纳米级光滑表面=Float polishingsubnanometer—smooth surface[刊,中]/高宏刚,曹健林,陈星旦(中科院长春光机所应用光学国家重点实验室。吉林,长春(130022))∥光学学报。—1995,15(6)。—824—825 对现阶段进行的超光滑表面浮光抛光研究进行了总结,介绍了浮法抛光原理样机的基本结构,以及实现亚纳米浮法抛光的主要条件,并给出了亚纳米级光滑表面的检测结果。图2(严寒)

凸轮轴表面粗糙度光整技术研究

分析了电控燃喷系统用凸轮轴表面粗糙度的设计目标和实际磨削加工能力,提出了凸轮轴光整加工的必要性,结合凸轮轴表面粗糙度技术条件,对备选的砂带抛光研磨光整和滚磨光整2种技术方案,从光整效果和工艺成本角度进行比较,分析结果表明,滚磨光整技术更具比较优势,除降低粗糙度外,还能有效改善其表面纹理、耐磨性、疲劳强度和清洁度,有利于提高整体燃喷系统的工作性能和可靠性,项目实施效果良好。

300 mm×600 mm规格免抛柔光釉瓷砖生产工艺

本文主要针对目前陶瓷行业流行的柔光釉瓷砖的生产工艺进行阐述,并且把抛光柔光釉砖和免抛光柔光釉砖进行对比,对其生产过程中所产生的质量问题进行简单的分析。

氟烷基硅烷改性硅树脂陶瓷防污剂研制及应用

通过添加甲基三氟丙基二甲氧基硅烷来改性硅树脂陶瓷防污剂可明显地改善防污剂的耐油性污渍的性能,同时氟烷基硅烷改性硅树脂陶瓷防污剂保持了有机硅树脂防污剂的持久防污性能的优点。用金相显微镜、扫描电镜观察抛光砖表面孔隙的变化。

STUDIES ON POLYURETHANE FOAM POLISHING TOOL

This paper deals with Polyurethane Foam Polishing Tool (PFPT), which has three dimensional softness and are adapted to polishing sophisticated curved surfaces. The manufacturing technology, the equilibrium theory of matter and energy have been discussed and the PFPT is produced successfully at our laboratory. After investigating their properties, the effective factors to the behavior of the PFPT are studied. The microcosmic construction of the PFPT have been observed by sweep electron microscope(SEM) and the polishing mechanism studied. A great deal of experiments have been carried out to optimize the manufacturing parameters.

Linearity of Removal in the Proeess of Optical Element Polishing

In the light of some assumptions that are very close to the practical working conditions,a very complicated polishing process of optical element can be simplified as a linear and shift invariant system that is relatd only to the speed,pres- sure and time of processing.In polishing,the removed material can be represented and entreated by the convolution of the removal function of polishing head and the dwell function.The properties of removal function are presented.The assumptions and methods given by the author have been shown to be correct and applicable by experiments using a ring lap to polish the optical surfac.

Research on transmission character of side polished fiber

Transmission characteristics of the side polished fiber were studied by experimental method.The side polished fibers with different depth and length were implemented,and the corresponding wavelength dependent loss was measured.Based on wheel fabrication,the side polished fibers were achieved with the low insertion loss and cost.Meanwhile,they can be artificially controlled for the use of evanescent field area and easy to system integration.

Design of fiber-optic collector for spectrometer based on curved mirror

To enlarge the detection range of traditional fiber-optic spectrometer,two rotating parabolic mirrors were first used in the design of fiber-optic collector for spectrometer,which can extend the detection range of spectrometer from centimeter-scale to50m,as a super-low altitude remote sensing detector under passive lighting conditions.According to the performance requirements of fiber-spectrometer for optical collector,this study deduced the calculation formulae of design size of parabolic optical collector applied to different sensitivity spectrometers,different detection targets,different detection ranges and different weathers.Based on the calculation results,the model of fiber-optic collector with a diameter of16mm and a height of7.8mm was designed by ZEMAX.And then,TracePro,a light simulation software,was applied to ray tracing.The simulation results of optical radiation magnification agrees well with theoretical value,and the relative error is less than0.78%.This optical collector can effectively extend the detection range of spectrometer and expand its application fields and scopes.Compared with traditional refractive optical collector,it has several advantages of compact structure,low weight and low cost.

Influences of polishing on return loss of optical fiber connectors

With Al2O3 and SiO2 as polishing medium, under different polishing conditions, e.g. with different polishing pressure, polishing time and polishing fluid, the influences of polishing treatment on the return loss of optical fiber connectors were investigated. The return loss of optical fiber connectors is 32CD*238dB before polishing. The results show that dry polishing（i.e. no polishing fluid） with Al2O3 has less influence on return loss of optical fiber connectors, while dry polishing with SiO2 reduces return loss to about 20dB because of the end-face of optical fiber contaminated. The wet polishing（i.e. using distilled water as polishing fluid） with Al2O3 or SiO2 can increase return loss to 45CD*250dB, but wet polishing with Al2O3 may produce optical fiber undercut depth of 80CD*2140nm. Wet polishing with SiO2 should be preferentially selected for optical fiber connectors and polishing time should be controlled within 20CD*230s.

Ultrasonic magnetic abrasive finishing

Put forward a new kind of polishing method,ultrasonic magnetic abrasive fin-ishing(UMAF),and studied its mechanism of improving polishing efficiency.By analyzingall kind of forces acting on single abrasive particle in the polishing process and calculatingthe Size of the composition of forces,get the conclusion that UMAF will enhance the effi-ciency of the normal magnetic abrasive finishing(MAF)due to the ultrasonic vibration in-creases the cutting force and depth.At last the idea of designing the UMAF system basedon numerical control milling machine is put forward which is convenient to setup and willaccelerate the practical application of MAF.

Ion Beam Polishing for K9 Glass

K9 glass is a common material of optics and micro system, with cheaper price and better processing function. With the development of the optical and micro system, the technique of manufacturing micron/nanometer dimensions microstructure and micro device on K9 glass has used in photoelectron, microwave and diffraction optics device et al The coarse surface of optics and microwave device can cause the light scattering and signal losing, and the function of device reduced. So the supersmooth surface plays an important role in optic and microwave device.

Linear and Nonlinear Optical Absorptions of a Hydrogenic Donor in a Quantum Dot Under a Magnetic Field

The linear and nonlinear optical properties of a hydrogenic donor in a disc-like parabolic quantum dot in the presence of an external magnetic field are studied. The calculations were performed within the effective mass approximation, using the matrix diagonalization method and the compact density-matrix approach. The linear and nonlinear optical absorption coefficients between the ground （L =0） and the first excited state （L = 1） have been examined based on the computed energies and wave functions. We find that the linear, nonlinear third-order, and total optical absorption coefficients are strongly affected by the confinement strength of QDs, the external magnetic field, and the incident optical intensity.

Electrolyte composition and removal mechanism of Cu electrochemical mechanical polishing

The optimization of electrolytes and the material removal mechanisms for Cu electrochemical mechanical planarization(ECMP)at different pH values including 5-methyl-1H-benzotriazole(TTA),hydroxyethylidenediphosphoric acid(HEDP),and tribasic ammonium citrate(TAC)were investigated by electrochemical techniques,X-ray photoelectron spectrometer(XPS)analysis,nano-scratch tests,AFM measurements,and polishing of Cu-coated blanket wafers.The experimental results show that the planarization efficiency and the surface quality after ECMP obtained in alkali-based solutions are superior to that in acidic-based solutions,especially at pH=8.The optimal electrolyte compositions(mass fraction)are 6% HEDP,0.3% TTA and 3% TAC at pH=8.The main factor affecting the thickness of the oxide layer formed during ECMP process is the applied potential.The soft layer formation is a major mechanism for electrochemical enhanced mechanical abrasion.The surface topography evolution before and after electrochemical polishing(ECP)illustrates the mechanism of mechanical abrasion accelerating electrochemical dissolution,that is,the residual stress caused by the mechanical wear enhances the electrochemical dissolution rate.This understanding is beneficial for optimization of ECMP processes.

Investigation on the cleaning of KDP ultra-precision surface polished with micro water dissolution machining principle

A potassium dihydrogen phosphate(KDP) optical crystal was machined to an ultra-precision surface with water-in-oil(W/O) micro emulsion polishing fluid. The micro water dissolution principle utilized in the machining process is discussed, its planarization mechanism is illustrated, and an ultra-precision polished surface with 2.205 nm RMS roughness is obtained. However, a substantial quantity of residual contamination remained on the polished surface after machining. This can seriously impact the optical performance of the crystal, and so it must be removed. Fourier transform infrared(FTIR) spectroscopy was used to conduct an investigation into the composition of the surface residue, and the results showed that the residue was comprised of organic chemicals with hydrocarbon chains and aromatic ether, i.e., mostly the polishing fluid. The cleaning method and the principle on which the KDP ultra precision surface investigation is based are discussed in detail, and the cleaning experiments with selected KDP-compatible organic solvents were then performed. FTIR transmittance spectra measurement and microscopic observations were employed to assess the effects of the cleaning process on the surface of the KDP crystal. The results showed that toluene cleaning achieved the most desirable results. This cleaning method produced a surface roughness of 1.826 nm RMS, which allows the KDP crystal to be applied to subsequent engineering applications.

Non-spherical abrasives with ordered mesoporous structures for chemical mechanical polishing

The chemical mechanical polishing(CMP)technology has been widely used for surface modification of critical materials and components with high quality and efficiency.In a typical CMP process,the mechanical properties of abrasives play a vital role in obtaining the ultra-precision and damage-free surface of wafers for improvement of their performances.In this work,a series of fine structured rod-shaped silica(RmSiO2)-based abrasives with controllable sizes and diverse ordered mesoporous structures were synthesized via a soft template approach,and successfully applied in the sustainable polishing slurry for improving the surface quality of cadmium zinc telluride(CZT)wafers.Compared with commercial silica gel,solid and mesoporous silica spheres,the RmSiO2 abrasives present superior elastic deformation capacity and surface precision machinability on account of their mesoporous structures and rod shapes.Especially,ultra-precision surface roughness and relatively effective material removal speed were achieved by the CMP process using the RmSiO2 abrasives with a length/diameter(L/d)ratio of 1.In addition,a potential CMP mechanism of the developed polishing slurry to CZT wafer was elucidated by analyzing X-ray photoelectron spectra and other characterizations.The proposed interfacial chemical and mechanical effects will provide a new strategy for improving abrasives’machinability and precision manufacture of hard-to-machine materials.