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排序方式: 共有105条查询结果,搜索用时 31 毫秒
91.
92.
MSM7512B是OKI公司推出的嵌入式调制解调器,文中在介绍了MSM7512B的特点和引脚功能的基础上,给出了MSM7612B与AT89C205单片机的接口电路及软件编程,并结合现代城市交通控制系统的实际应用进行了讨论。 相似文献
93.
94.
采用分子束外延(MBE)方法在Al2O3(0001)基片上生长了β-Ga2O3薄膜,利用XRD、SEM和AFM对薄膜的结构和形貌特性进行了表征。制作了基于β-Ga2O3薄膜的金属-半导体-金属(MSM)结构紫外探测器并对其进行了电学特性测试,结果表明:在20 V偏压下,器件的暗电流为8 nA;在波长为254 nm、光照强度为13×10–6W/cm2的紫外光照射下,器件的光电流为624 nA;器件的光电流与暗电流比值为78,光响应度达360 A/W,表现出明显的日盲紫外光响应特性。 相似文献
95.
We analyze the reheating in the modification of the ν MSM (Standard Model with three right handed neutrinos with masses below the electroweak scale) where one of the sterile neutrinos, which provides the Dark Matter, is generated in decays of the additional inflaton field. We deduce that due to rather inefficient transfer of energy from the inflaton to the Standard Model sector reheating tends to occur at very low temperature, thus providing strict bounds on the coupling between the inflaton and the Higgs particles. This in turn translates to the bound on the inflaton mass, which appears to be very light 0.1 GeV?mI?10 GeV, or slightly heavier then two Higgs masses 300 GeV?mI?1000 GeV. 相似文献
96.
Tungsten oxide nanowires of diameters ranging from 7 to 200~nm are
prepared on a tungsten rod substrate by using the chemical vapour
deposition (CVD) method with vapour--solid (VS) mechanism. Tin
powders are used to control oxygen concentration in the furnace,
thereby assisting the growth of the tungsten oxide nanowires. The
grown tungsten oxide nanowires are determined to be of crystalline
W18O49. I--V curves are measured by an \textit{in
situ} transmission electron microscope (TEM) to investigate the
electrical properties of the nanowires. All of the I--V curves
observed are symmetric, which reveals that the tungsten oxide
nanowires are semiconducting. Quantitative analyses of the
experimental I--V curves by using a metal--semiconductor--metal
(MSM) model give some intrinsic parameters of the tungsten oxide
nanowires, such as the carrier concentration, the carrier mobility
and the conductivity. 相似文献
97.
新型MSM结构砷化镓半导体探测器的性能 总被引:1,自引:1,他引:0
研究一种新型双金属接触GaAs半导体探测器的性能,测量了241Am 5.48MeVα粒子、57Co 122keV的光子和90Sr 2.27MeVβ粒子的最小电离粒子谱,比较了一个3×3mm2的GaAs芯片在经过137Cs 662keV光子约1300rad辐照前后的电荷收集效率和能量分辨率.测量结果显示这种新型金属─半导体─金属(MSM)结构的半导体探测器不仅在室温下对各种粒子具有良好的探测能力,而且具有很好的抗辐照性能. 相似文献
98.
4H-SiC based metal-semiconductor-metal (MSM) photodetectors with diverse spacing were designed, fabricated, and characterized,
in which nickel Schottky contacts were needed. Current-voltage and spectral responsivity measurements were carried out at
room temperature. The fabricated 4 μm-spacing device showed a very low dark current (0.25 pA at 5 V bias voltage), a typical
responsivity of 0.103 A/W at 20 V, and a peak response wavelength at 290 nm. The fabricated devices held a high DUV to visible
rejection ratio of >103. 相似文献
99.
本文使用数值计算方法建立了4H-SiC金属-半导体-金属紫外光探测器的二维模型。通过求解泊松方程,电流连续方程以及电流密度方程计算了该探测器依赖于器件结构的响应度。计算结果与实验数据符合较好,验证了模型的正确性。考虑到金属电极对紫外光的反射和吸收,详细研究了各种器件参数对响应度的影响并分析了其工作机理。结果表明响应度与电极高度成反比并随电极间距和宽度的增加而增加。紫外可见比大于1000。通过优化探测器结构,电极高度为50 nm电极宽度和间距为3 μm 和9 μm的探测器在10V偏压下具有最高响应度 180.056 mA/W,同时该探测器的峰值量子效率和最大紫外可见比分别为77.93%和1875。 相似文献
100.
In this work, we present the influence of dimensional parameters on dark current and photocurrent of the metal-semiconductor-metal photodetector (MSM). MSM photodetectors of different sizes have been fabricated on GaAs (NID). The active area of MSM samples varies between 1×1 μm2 and 10×10 μm2 with equal electrodes spacing and finger widths (l=D) varying between 0.2 and 1 μm. The I(V) characterization in inverse and direct polarization in darkness shows good symmetry of curves, which shows the good performance of components and successful fulfillment of the Schottky contacts. The application of laser fiber of incident light power of 16 mW at wavelength of 850 nm for the illumination of the MSM photodetectors showed the evolution of the photocurrent ranging from 0.75 to 1.81 mA, respectively, for 1 to 0.2 μm electrodes spacing at 3 V and active area S=3×3 μm2. We showed also that variation ranging from 0.45 to 2.5 mA, respectively, for S=1×1 μm2 to S=10×10 μm2 at 3 V and 0.3 μm electrodes spacing. The resistance of MSM photodetectors obtained evolved proportionally to the electrodes spacing (0.87 kΩ for D=0.2 μm and 2.27 kΩ for D=1 μm with S=3×3 μm2) and inversely proportional to the surface area (2.02 kΩ for S=1×1 μm2, and 0.56 kΩ for S=10×10 μm2 with 0.3 μm inter electrodes spacing). 相似文献