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561.
为提高硅晶片双面超精密抛光的抛光速率,在分析双抛工艺过程基础上,采用自制大粒径二氧化硅胶体磨料配制了SIMIT8030-I型新型纳米抛光液,在双垫双抛机台上进行抛光实验. 抛光液、抛光前后厚度、平坦性能及粗糙度通过SEM、ADE-9520型晶片表面测试仪、AFM进行了表征. 结果表明:与进口抛光液Nalco2350相比,SIMIT8030-I型抛光液不仅提高抛光速率40% (14μm/h vs 10μm/h) ;而且表面平坦性TTV和TIR得到改善;表面粗糙度由0.4728nm降至0.2874nm,即提高抛光速率同时显著改善了抛光表面平坦性和粗糙度. 相似文献
562.
563.
In this paper the influences of slurry chemistry and thickness of the copper layer on dishing will be discussed. The dishing is studied for different patterns and variable polishing times. We found that the concentration of the oxidiser and the thickness of copper layer have a strong impact on dishing. The larger Cu features develop dishing at a higher rate than smaller structures during overpolishing. The experimental results lead to the following hypothesis for the Cu removal and surface passivation. The oxidizer (H2O2) reacts with Cu in an acidic slurry (pH 4) and Cu2+ ions are formed. The anions of the carboxylic acid react with Cu2+ ions and form an insoluble salt (R(COO)2Cu) which passivates the surface. This passivation layer is removed in protruding areas by mechanical abrasion. Once removed from the surface, the ‘metallic soap’ particles are swept away by the turbulent motion in the slurry. 相似文献
564.
单点金刚石车削铝合金表面具有较好的表面质量和精度,但车削纹路会产生散射现象,难以满足高品质光学系统要求。对铝合金表面进行直接光学抛光可以去掉表面产生的车削纹路,提高反射表面的光学性能,分析酸性条件下和碱性条件下的铝镜抛光原理,采用新型抛光盘与抛光液对单点金刚石车削后铝合金表面进行抛光实验。实验结果表明:通过合理控制工艺参数,能够消除铝合金表面残留的周期性车削刀纹,并且不会产生新的表面划痕,得到较好的铝镜光学表面质量,测得的铝镜表面粗糙度Ra=2.6 nm。 相似文献
565.
566.
通过将多块不同尺寸的碳化硅平面试片以及一块口径为520mm碳化硅凹非球面反射镜作为镜面改性工艺技术的实验平台,对大口径碳化硅反射镜面PVD改性工艺技术进行探索、分析和研究。重点研究了前期PVD改性前镜面特性与PVD改性层的最佳匹配关系,主要是PVD改性层与镜面粗糙度和残留面形误差的要求和最佳结合点。采用的抛光方式为磨盘相对镜体做行星运动,采用相同的离子束辅助沉积法进行凹椭球面碳化硅反射镜的镜面改性。实验结果表明:通过选用合适的方案对改性后的PVD改性层镜面的面形误差进行修抛,可同时提高其镜面光洁度和粗糙度,最终测试结果为0.756 nm(Sq),与改性前比较,粗糙度得到一定程度的提高。 相似文献
567.
Etching and chemical mechanical polishing (CMP) experiments of the MgO single crystal substrate with an artificial scratch on its surface are respectively performed with the developed polishing slurry mainly containing 2 vol.% phosphoric acid (H3PO4) and 10-20 nm colloidal silica particles, through observing the variations of the scratch topography on the substrate surface in experiments process, the mechanism and effect of removing scratch during etching and polishing are studied, some evaluating indexes for effect of removing scratch are presented. Finally, chemical mechanical polishing experiments of the MgO substrates after lapped are conducted by using different kinds of polishing pads, and influences of the polishing pad hardness on removal of the scratches on the MgO substrate surface are discussed. 相似文献
568.
随着军用光学仪器的飞速发展,红外光学材料单晶硅广泛应用于红外光学元件和半导体行业,为了满足精密仪器对光学系统的要求,对光学元件的面型精度要求越来越高。针对红外跟踪系统中对高精度单晶硅透镜的加工技术要求,以Ф26 mm的单晶硅透镜为例,通过多次反复研磨修抛和检测分析,并不断优化工艺参数,设计了特殊的夹具,解决了单晶硅表面光洁度问题以及中心偏差难以控制的加工技术难题,并实现了批量生产。经检测,单晶硅非球面面形精度达到0.2 m,表面光洁度达到Ⅲ级以上,中心偏差在1 m以内,各项参数均满足了红外跟踪系统的要求。 相似文献
569.
A. K. Sikder Ashok Kumar P. Shukla P. B. Zantye M. Sanganaria 《Journal of Electronic Materials》2003,32(10):1028-1033
Electroplated (EP) Cu films demonstrate a microstructural transition at room temperature, known as self-annealing, that involves
grain growth and texture changes. In this paper, we have investigated the annealing behavior of EP Cu films grown on a Cu
seed layer deposited on top of a TaN barrier layer. A grazing incident x-ray diffraction (GIXRD) pattern shows stronger x-ray
reflections form Cu (111) and (220) planes but weaker reflections from (200), (311), and (222) planes in all the EP Cu samples.
Nanoindentation was performed on all the samples using the continuous stiffness measurement technique. The elastic modulus
varied from 121 GPa to 132 GPa, while the hardness varied from 1 GPa to 1.3 GPa, depending on the annealing conditions. The
surface morphology and roughness of the Cu films were characterized using atomic force microscopy (AFM). The tribological
properties of the copper films were measured using the Bench Top chemical mechanical polishing (CMP) tester (CETR, Inc., Campbell,
CA). Nanoindentation was performed on the samples after CMP, and an increase in hardness and modulus was observed. This may
be attributed to the work hardening of the Cu films during CMP. 相似文献
570.
High-quality conformal silicon oxide films prepared by multi-step sputtering PECVD and chemical mechanical polishing 总被引:4,自引:0,他引:4
Min Park Hyun Kyu Yu Jin Gun Koo Jin Jang Kee Soo Nam 《Journal of Electronic Materials》1998,27(11):1262-1267
High-quality conformal oxide films were obtained by using multi-step sputtering (MSSP) plasma enhanced chemical vapor deposition
(PECVD) process with argon ion sputtering and chemical mechanical polishing (CMP). The repeated deposition by plasma enhanced
chemical vapor deposition (PECVD) and anisotropic etching of oxide films by multi-step sputtering PECVD improve the step coverage
and gap filling capability significantly. The argon plasma treatment enhances the binding energy of Si-O in the SiO2 network, and the temperature dependence of stress for MSSP oxide film showed no hysteresis after the heating cycle up to
440 °C. The stress-temperature slope of MSSP oxide film was found to be much less than that of conventional PECVD oxide film.
The slope for 1.1 μm thick film is about 5.8×105 dynes/cm2/°C which is smaller than that of thermally grown oxide film. It seems that MSSP oxide film reduces stress-temperature hysteresis
and becomes more dense and void-free in the narrow gaps with inter-metal spacing of 0.5 μm. After filling of the narrow gap,
we adopted the CMP process for global planarization and obtained good planarization performance. The uniformity of the film
thickness was about 4% and the degree of the planarization was over 95% after CMP process. 相似文献