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介绍一种大功率、调压范围宽的开稳压电源。主电路采用单端正激式结构,控制电路简单、工作可靠、维修方便。 相似文献
54.
用射频分子束外延技术研制出了室温迁移率为10 35 cm2 /(V·s) ,二维电子气浓度为1.0×10 1 3cm- 2 ,77K迁移率为2 6 5 3cm2 /(V·s) ,二维电子气浓度为9.6×10 1 2 cm- 2 的Al Ga N/Ga N高电子迁移率晶体管材料.用此材料研制的器件(栅长为1μm,栅宽为80μm,源-漏间距为4μm )的室温非本征跨导为186 m S/m m,最大漏极饱和电流密度为92 5 m A/m m,特征频率为18.8GHz. 相似文献
55.
本文对微波场效应管Ⅰ—Ⅴ特性模型进行了研究,分析比较了八种常用模型的优缺点,它可为微波电路的设计提供一个实用的参考依据.在模型参数提取中,我们采用了一种新算法,先应用一个基于主成份灵敏度分析的空间坐标变换,然后采用Levenberg-Marquardt算法进行优化拟合.实际计算表明,此法能够快速、精确地提取模型参数. 相似文献
56.
In this paper, the design geometry of Ferroelectric Dopant Segregated Schottky Barrier Tunnel Field Effect Transistor (Fe DS-SBTFET) has been proposed. Various electrical properties such as ION/IOFF ratio and subthreshold swing (SS) of the proposed design have been premeditated and compared with different asymmetric structures. The impact of various types and thickness of buffer on the ferroelectric properties have been analysed. The device has been optimised for various doping concentrations and lengths of the dopant segregated layer (DSL). The digital applications of the proposed device in terms of complementary TFET digital inverter circuit have been studied. The transient characteristics and the delay parameters by considering various ferroelectric thicknesses have been analysed. Moreover, the transfer characteristics and electric field have been explored in the presence and absence of ferroelectric layer to obtain a better insight into the ferroelectric properties of the proposed structure. The electric field at the tunnelling junction is enhanced by the presence of ferroelectric layer which improves the ON current. The structure with ferroelectric thickness of 6 nm provides the best ION/IOFF ratio of 1.2 × 109 and SS of 14 mV/dec. 相似文献
57.
Mitsue Takahashi Kazushi Kodama Toshiyuki Nakaiso Minoru Noda Masanori Okuyama 《Integrated ferroelectrics》2013,141(1-5):125-134
Abstract Retention characteristics of MFIS (metal-ferroelectric-insulator-semiconductor) structures have been investigated theoretically and experimentally. The simulated retention characteristics have indicated that reducing current through the ferroelectric layer is very effective to make the retention time long. In order to reduce the current through the ferroelectric layer, an MFIS with an improved ferroelectric layer and an M-I-FIS (metal-insulator-ferroelectric-insulator-semiconductor) have been investigated theoretically. Both of them have given good retention characteristics. Experimentally, retention characteristics of MFIS have been much improved by annealing, which is considered to suppress the current density in the ferroelectric layer, although those of M-I-FIS have been improved a little. 相似文献
58.
The interfacial reactions between Sn-3.0 Ag-0.7 Cu solder and backside metallizations on two semiconductor devices, field-effect
transistors (FET) and diode, are studied. The metallizations on both devices were vacuum evaporated Ti/Ni/Ag. The intermetallic
compounds (IMC) formed near the diode/solder and FET/solder joints during reflow, and the interdiffusion processes during
solid state aging are characterized by the quantitative energy dispersive x-ray analysis and the x-ray mapping technique in
a scanning electron microscope. Two different intermetallic compounds are found near the diode/solder interface. Both are
in the form of particles, not a continuous layer, and are referred to as IMC-I and IMC-II. IMC-I corresponds to Ni3Sn4, with Cu atoms residing on the Ni sublattice. It is uncertain whether IMC-II is Cu6Sn5 or a Cu-Ni-Sn ternary phase. Near the as-reflowed FET/solder interface, both isolated scallops and a skeleton-like layer
of Ni3Sn4 are observed. The primary microstructural dynamics during solid-state aging are the coarsening of IMCs and the reactions
involving the Ni-and Ti-layer with Sn and Au. While the reaction with the Ni-layer yields only Ni3Sn4 intermetallic, the reaction involving the Ti-layer suggests the formation of Ti-Sn and Au-Sn-Ti intermetallics. The latter
is due to the diffusion of Au from the substrate side to the die side. It is postulated that the kinetics of the Au-Sn-Ti
layer is primarily governed by the diffusion of Au through the Ni3Sn4 layer by a grain boundary mechanism. 相似文献
59.
2~6GHz单片功率放大器 总被引:8,自引:0,他引:8
报道了有耗匹配宽带单片功率放大器的研究方法和结果。该两级单片功放电路采用自建的 Root非线性模型进行了谐波平衡分析。在 2 .0~ 6.7GHz频带上线性增益为 17d B,平坦度为± 0 .75d B,输入和输出驻波分别小于 2。全频带上 ,饱和输出功率为 1~ 1.4 W,功率附加效率大于2 0 %。该宽带单片功率放大器在 76mm Ga As单片 MMIC工艺线上用全离子注入、0 .5μm栅长工艺研制完成 ,电路芯片面积为 0 .1mm× 2 .6mm× 2 .7mm。 相似文献
60.
GaAs微波单片集成电路中器件的精确建模 总被引:1,自引:0,他引:1
论述了精确模型的建立对于微波单片集成电路研制和产品开发的重要意义 ,介绍了工程模型的概念和提取模型的方法 ,给出了在南京电子器件研究所进行的 MMIC有源器件的建模实例及验证结果。 相似文献