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51.
GaAs单片集成电路具有体积小、质量轻和可靠性高等特性,已经成为微波领域重要的器件。采用MBE技术生长出双面掺杂AlGaAs/InGaAs PHEMT结构的外延材料,研制了高效率的GaAs PHEMT器件,S波段功率附加效率大于55%。建立了基于EEHEMT的大信号模型,利用ADS软件搭建了有耗匹配的二级放大电路拓扑结构,进行最佳效率匹配,得到优化电路。采用4英寸(1英寸=2.54cm)GaAs0.35μm标准工艺研制了AlGaAs/InGaAs/GaAsPHEMT MMIC电路,测试结果表明,在测试频率为2.2~3.4GHz,测试电压VDS为10V时,输出功率大于12W,功率增益大于22dB,功率附加效率大于40%。 相似文献
52.
D. L. Huffaker Z. Z. Zou G. Park O. B. Shchekin D. G. Deppe 《Journal of Electronic Materials》1999,28(5):532-536
Data are presented characterizing the spectral emission and electroluminescence efficiency dependence on temperature of InGaAs/GaAs
quantum dots that result in 1.3 μm lasing at room temperature. Efficient ground state emission is achieved at 80K, but the
spontaneous efficiency decreases with increasing temperatures. The ground state spectral width is 26 meV at 80K and 31 meV
at 300K. Ground state lasing is obtained over a wide range of temperatures, with an ultralow threshold current density of
14 A/cm2 obtained at 80K. 相似文献
53.
Daniel C. Bertolet Jung-Kuei Hsu Farid Agahi Kei May Lau 《Journal of Electronic Materials》1990,19(9):967-974
In this paper we describe a study of strained quantum wells (QWs) as a means to experimentally observe the critical thickness
(h
c) for the formation of interfacial misfit dislocations. Two material systems were investigated: GaAs/In0.11Ga0.89As, in which the QW layers are under biaxialcompression, and Al0.35Ga0.65As/GaAs0.82P0.18, in which the QW layers are under biaxialtension. Samples were grown by atmospheric pressure organometallic chemical vapor deposition, and characterized by low-temperature
photoluminescence (PL), x-ray diffraction, optical microscopy, and Hall measurements. For both material systems, the observed
onset of dislocation formation agrees well with the force-balance model assuming a double-kink mechanism. However, overall
results indicate that the relaxation is inhomogeneous. Annealing at 800–850° C had no significant effect on the PL spectra,
signifying that even layers that have exceededh
c and have undergone partial relaxation are thermodynamically stable against further dislocation propagation. 相似文献
54.
LP-MOCVD生长InGaAs/InP应变量子阱的研究 总被引:2,自引:1,他引:1
本文研究了LP-MOCVD对不同x值的In1-xGaxAs/InP生长条件,并且生长了压缩应变为0.5%三个不同阱宽的InGaAs/InP量子阱结构,利用77KPL光谱分析了能级同阱宽的关系,实现最窄阱宽为4.4nm,最小全半高峰宽为17.0mev. 相似文献
55.
56.
57.
Noriyuki Miyata Hiroyuki IshiiYuji Urabe Taro ItataniTetsuji Yasuda Hisashi YamadaNoboru Fukuhara Masahiko HataMomoko Deura Masakazu SugiyamaMitsuru Takenaka Shinichi Takagi 《Microelectronic Engineering》2011,88(12):3459-3461
Electrical and physical characteristics of the Al2O3/InGaAs interfaces with (1 1 1)A and (1 0 0) orientations were investigated in an attempt to understand the origin of electron mobility enhancement in the (1 1 1)A-channel metal-insulator-semiconductor field-effect-transistor. The (1 1 1)A interface has less As atoms of high oxidation states as probed by X-ray photoelectron spectroscopy. The electrical measurements showed that energy distribution of the interface traps for the (1 1 1)A interface is shifted toward the conduction band as compared to that for the (1 0 0) interface. Laterally-compressed cross-section transmission electron microscopy images showed that the characteristic lengths of the interface roughness are different between the (1 1 1)A and (1 0 0) interfaces. The contributions of the Coulomb and roughness scattering mechanisms are discussed based on the experimental results. 相似文献
58.
59.
The effect of drain-source voltage on A1GaAs/InGaAs PHEMTs thermal resistance is studied by experimental measuring and simulation. The result shows that A1GaAs/InGaAs PHEMTs thermal resistance presents a downward trend under the same power dissipation when the drain-source voltage (VDs) is decreased. Moreover, the relatively low VDS and large drain-source current (IDs) result in a lower thermal resistance. The chip-level and package-level thermal resistance have been extracted by the structure function method. The simulation result indicated that the high electric field occurs at the gate contact where the temperature rise occurs. A relatively low VDS leads to a relatively low electric field, which leads to the decline of the thermal resistance. 相似文献
60.
采用气源分子束外延(GSMBE)生长了低温InGaAs材料,研究了生长温度及As压对InGaAs材料性质的影响,得到优化的生长条件为:生长温度为300 ℃、As压为77.3 kPa。通过Be掺杂,并采用In0.52Al0.48As/In0.53Ga0.47As多量子阱结构,将材料的方块电阻提高到1.632106 /Sq,载流子数密度降低至1.0581014 cm-3。X射线衍射结果表明:InGaAs多量子阱材料具有较高的晶体质量。这种Be掺杂InGaAs多量子阱材料缺陷密度大且电阻率高,是制作太赫兹光电导天线较理想的基质材料。收稿日期:; 修订日期: 相似文献