首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   551篇
  免费   133篇
  国内免费   41篇
化学   317篇
晶体学   2篇
力学   10篇
综合类   2篇
物理学   394篇
  2024年   1篇
  2023年   2篇
  2022年   5篇
  2021年   10篇
  2020年   18篇
  2019年   7篇
  2018年   13篇
  2017年   16篇
  2016年   23篇
  2015年   35篇
  2014年   42篇
  2013年   49篇
  2012年   39篇
  2011年   62篇
  2010年   41篇
  2009年   56篇
  2008年   53篇
  2007年   46篇
  2006年   48篇
  2005年   28篇
  2004年   32篇
  2003年   25篇
  2002年   21篇
  2001年   10篇
  2000年   14篇
  1999年   2篇
  1998年   5篇
  1997年   4篇
  1996年   2篇
  1995年   3篇
  1994年   2篇
  1993年   3篇
  1992年   1篇
  1991年   1篇
  1990年   1篇
  1988年   1篇
  1987年   2篇
  1984年   1篇
  1981年   1篇
排序方式: 共有725条查询结果,搜索用时 15 毫秒
41.
In this study, after Dill’s model is discussed for transmittance and refractive indices of the non-chemically amplified resists, G- and I-line novolak resists, and the chemically amplified resists, a modification of Dill’s model as a new exposure model is introduced. The simulation results obtained using this new model with the multi-thin film interface method and the Berning theory have shown a good matching to the experimental data. Also, the simulated transmittance change due to the exposure parameters are used to analyze the influence of the coefficients on the transmittance.  相似文献   
42.
 为了精确地确定电子束曝光剂量与刻蚀深度间的关系,根据抗蚀剂的灵敏度曲线,采用反差经验公式来确定剂量与刻蚀深度间的关系。选用正性抗蚀剂PMMA进行曝光实验,将计算值进行曲线拟合,得到的关系曲线与实验结果基本相符。当剂量在20~35 μC/cm2间时,实验值与计算值间的差值最小,说明当剂量在此范围内时该方法能够更加精确地确定剂量与刻蚀深度间的关系。采用该方法节省了实验时间,提高了刻蚀效率。  相似文献   
43.
D.Hitz 《中国物理 C》2007,31(Z1):123-127
As they are first optimized for their ion losses,ECRISs are always under a fundamental compromise: having high losses and strong confinement at the same time.To help ECR ion source developers in the design or improvement of existing machines,general comments are presented in a review article being soon published. In this 160 pages contribution,fundamental aspects of ECRISs are presented,with a discussion of electron temperature and confinement and ion confinement.Then,as microwaves play a key role in these machines, a chapter presents major guidelines for microwave launching and coupling to ECR plasma.Moreover,once ECR plasma is created,understanding this plasma is important in ion sourcery;and a section is dedicated to plasma diagnostics with an emphasis on the determination of electron and ion density and temperature by vacuum ultraviolet(VUV)spectroscopy.Another chapter deals with the role of magnetic confinement and presents updated scaling laws.Next chapter presents different types of ECRISs designed according to the main parameters previously described.Finally,some industrial applications of ECRISs and ECR plasmas in general are presented like ion implantation and photon lithography.Some hints taken from this review article are presented in the following article.  相似文献   
44.
45.
46.
47.
Electrograining of aluminium in hydrochloric acid is one of the most commonly used processes for manufacturing printing lithographic plates. Two of the main features to be taken into account are the final morphology of the electrograined surface and the susceptibility of the alloy to be processed or, more specifically, the speed of the processing line. Both issues determine the efficiency of the production in terms of quality and time. In this work, a widely used commercial aluminium alloy (1050) is compared with a new experimental one (1050 modified with Zn) and with a higher strength alloy (namely 1020). In order to analyse their response to a.c. graining in HCl for high‐speed lines, some techniques such as image analysis or interferometry have been used. In general, the alloys doped with Zn and Mg present a better response to litho processing in terms of graining activity and reduction of streakiness when treatment of lower time periods is applied due to their influence as pitting initiators. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
48.
Highly conductive and transparent poly(3,4-ethylenedioxythiophene) (PEDOT) thin films can be prepared effectively via vapor-phase polymerization (VPP) with the addition of imidazole (Im) based derivatives. The addition of Im that has one and/or two alkyl substituents significantly improved the electrical conductivity of PEDOT thin films. In an effort to develop a facile PEDOT micro-patterning method, we investigated ink-jet printing and soft lithography. The procedure of oxidant patterning with a weak base followed by VPP of a 3,4-ethylenedioxythiophene (EDOT) monomer provides an effective and simple method for micro-patterning of an intrinsic conductive polymer (ICP).  相似文献   
49.
A distributed feedback (DFB) waveguide cavity with erbium-tris(8-hydroxyquinoline) has been fabricated by X-ray interference lithography in a laboratory-scale apparatus. The DFB cavity consists of a large area () one-dimensional grating of polymethylmethacrylate on Si (1 0 0). Structural, morphological and optical properties of the device have been studied. On-grating narrowing of the photoluminescence emission has been observed for the 492 nm grating period in correspondence to the 4f-4f Er band peak (at 1530 nm), indicating the possibility of optical gain for applications in the telecommunications.  相似文献   
50.
In this paper, we demonstrate the monolithic integration of a conventional waveguide, a photonic crystal demultiplexer, a photonic crystal taper coupler, photonic crystal waveguides, and photodiodes in InGaAsP-based material to form a planar nano-optics system. Photonic crystal demultiplexers consist of hexagonally arranged air holes. Finite-difference time-domain method is implemented to investigate the performance of the demultiplexer. The system is fabricated using e-beam lithography and conventional photolithography. The input light at wavelengths of 1530 and 1550 nm can be separated using the demultiplexing system. These can then be detected by photodiodes that exhibit a wide-bandwidth performance of 22 GHz.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号