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11.
FENG Ying HUANG ShiHua KANG Kai & FENG YuGuang Institute of Optoelectronic Technology Beijing Jiaotong University Beijing China 《中国科学:信息科学(英文版)》2010,(1)
The influence of channel length on the performances of carbon nanotube field effect transistors(CNT-FETs) has been studied.Buffered oxide etching was used to remove approximately a 60 nm layer from the original 100 nm silicon dioxide layer,to thin the dielectric layer of the back gate.Channel length of the CNT-FETs was changed along with the etching process.The dependence of drain-source current on gate voltage was measured to analyze the performance of the CNT-FETs,including the transconductance,carrier mo... 相似文献
12.
Shigeaki Yamamoto Yoshiaki Ukita Kozo Mochiji Yuichi Utsumi 《Electrical Engineering in Japan》2012,178(4):49-54
Polytetrafluoroethylene (PTFE) is a very attractive material for various fields because of its chemical resistance, insulation properties, and hydrophobic properties. However, it is difficult to fabricate PTFE microstructures with conventional techniques such as semiconductor processes or micromachining. We have succeeded in the fabrication of high‐aspect‐ratio microfluidics parts from PTFE by direct in‐vacuum photo‐etching utilizing synchrotron radiation (SR) at energy levels from 2 to 12 keV. This paper presents an analysis of the mechanisms of the PTFE microfabrication process and describes newly discovered processing characteristics of PTFE. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 178(4): 49–54, 2012; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21152 相似文献
13.
J. Zhu N. W. Emanetoglu Y. Chen B. V. Yakshinskiy Y. Lu 《Journal of Electronic Materials》2004,33(6):556-559
This paper describes the optimized process of wet-chemical etching of a ZnO film grown on an r-plane sapphire. Different etchants
and solution ratios have been used to achieve controllable etching rate and steep etching profile. With selected etching solutions,
the etching profiles of epitaxially grown ZnO films (>1.3 μm) are improved. Using Al instead of photoresist as the mask generates
a steeper etching slope. Maximal 1:1 vertical/horizontal ratio (45°) has been achieved. X-ray photoelectron spectroscopy (XPS)
and sheet resistance measurements show that this wet-chemical etching process has negligible influence on the modification
of the physical and chemical properties of the etched surface. 相似文献
14.
A plasma is a collection of charged particles and on average is electrically neutral. In fabricating integrated circuits, plasma etching is a key means to transfer a photoresist pattern into an underlayer material. To construct a predictive model of plasma‐etching processes, a polynomial neural network (PNN) is applied. This process was characterized by a full factorial experiment, and two attributes modeled are its etch rate and DC bias. According to the number of input variables and type of polynomials to each node, the prediction performance of the PNN was optimized. The various performances of the PNN in diverse environments were compared to three types of statistical regression models and the adaptive network fuzzy inference system (ANFIS). As the demonstrated high‐prediction ability in the simulation results shows, the PNN is efficient and much more accurate from the point of view of approximation and prediction abilities. 相似文献
15.
16.
B.A. Park C.A. Musca J. Antoszewski J.M. Dell L. Faraone 《Journal of Electronic Materials》2007,36(8):913-918
Exposure of p-type HgCdTe material to Ar/H2-based plasma is known to result in p-to-n conductivity-type conversion. While this phenomenon is generally undesirable when aiming to perform physical etching for
device delineation and electrical isolation, it can be used in a novel process for formation of n-on-p junctions. The properties of this n-type converted material are dependent on the condition of the plasma to which it is exposed. This paper investigates the
effect of varying the plasma process parameters in an inductively coupled plasma reactive ion etching (ICPRIE) tool on the
carrier transport properties of the p-to-n type converted material. Quantitative mobility spectrum analysis of variable-field Hall and resistivity data has been used
to extract the carrier transport properties. In the parameter space investigated, the n-type converted layer carrier transport properties and depth have been found to be most sensitive to the plasma process pressure
and temperature. The levels of both RIE and ICP power have also been found to have a significant influence. 相似文献
17.
研究了一种基于BCB材料的牺牲层接触平坦化技术,用于红外焦平面阵列Post CMOS工艺之前对读出电路表面的平坦化,以利于微测辐射热计微桥阵列与读出电路的集成。利用该方法成功将2μm的电路表面突起,平坦化为表面起伏56 nm的平面,可替代会给器件带来颗粒和损伤的化学机械抛光(CMP)技术。并在该平坦层上方成功进行了非晶硅敏感薄膜的沉积、微桥结构的图形化以及同时作为牺牲层的BCB的释放。通过实验研究了BCB膜层的厚度与转速、固化温度的关系,实验发现BCB的收缩率随温度小范围变化,约为30%。研究了BCB的等离子刻蚀特性,表明该材料适合用等离子刻蚀的方法进行接触孔的刻蚀和牺牲层释放。最后,利用BCB牺牲层接触平坦化技术成功地在读出电路(ROIC)芯片上制作了160×120面阵的非制冷红外焦平面阵列。 相似文献
18.
Experimental verification of a low temperature (<20 °C), reactive plasma etch process for copper films is presented. The plasma etch process, proposed previously from a thermochemical analysis of the Cu-Cl-H system, is executed in two steps. In the first step, copper films are exposed to a Cl2 plasma to preferentially form CuCl2, which is volatilized as Cu3Cl3 by exposure to a H2 plasma in the second step. Plasma etching of thin films (9 nm) and thicker films (400 nm) of copper has been performed; chemical composition of sample surfaces before and after etching has been determined by X-ray photoelectron and flame atomic absorption spectroscopies. 相似文献
19.
20.
M. N. Charasse B. Bartenlian J. P. Hirtz A. Peugnet J. Chazelas G. Amendola 《Journal of Electronic Materials》1990,19(6):567-573
The growth of GaAs on patterned Si substrates is essential for the integration of GaAs and Si devices. Moreover this growth
may have to be done in wells to planarize the surfaces of the Si and GaAs devices for their interconnection. In this study,
GaAs is grown by MBE on such patterned Si substrates, with window width down to 3 μm, and a complete structural characterization
of the material is made by electron microscopy. In every case, SEM observations show a very good definition of the pattern
by the contrast of the flat surface of the monocrystalline GaAs compared to the very rough surface of the polycrystalline
GaAs. Cross-sectional observations by STEM or TEM on non-etched samples reveal that the quality of the monocrystalline GaAs
is at least as good in terms of defect density as that of the standard GaAs on Si. On samples etched with a plasma to produce
wells, grains often form against the Si sidewall. Chemical etching with lateral etching avoids contact of the growing GaAs
with the Si sidewall and subsequent grain formation. The crystalline quality obtained on etched samples is not as good as
on non etched samples. A way of preparing the wells to improve this crystalline quality is proposed. 相似文献