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41.
成功地制备了有SiO2钝化层和无SiO2钝化层的GaN基PIN结构核辐射探测器,并对二者的I-V特性进行了测试。实验结果表明,SiO2钝化层的存在显著地降低了GaN基PIN结构核辐射探测器的反向漏电流,在-40V的反向偏压情况下,漏电流约有2个数量级的降低。实验过程中观测到随着反向偏压的增大,SiO2钝化层对器件反向漏电流的抑制效应更明显。建立了一种表面沟道模型解释了SiO2钝化层对漏电流的影响。 相似文献
42.
43.
M. El Kazzi D.J. WebbL. Czornomaz C. RosselC. Gerl M. RichterM. Sousa D. CaimiH. Siegwart J. FompeyrineC. Marchiori 《Microelectronic Engineering》2011,88(7):1066-1069
Experiments to increase the specific capacitance of MOS capacitors consisting of HfO2 on a passivating interfacial layer (IL) of amorphous Si (a-Si) on GaAs are described. XPS analysis of the layers and electrical measurements on the capacitors are combined to study the evolution of the gate stack during deposition and subsequent heat treatments. It is shown that oxidation of the a-Si IL is a major factor in preventing the attainment of a scaled capacitance equivalent thickness (CET). By controlling the deposition of the layers, the gate metal and the heat treatments, a highly scaled gate stack with a CET of 1.2 nm and a leakage reduction of more than 4 orders of magnitude with respect to SiO2/Si was realized. 相似文献
44.
The temperature dependence of capacitance-voltage (C-V) and the conductance-voltage (G/w-V) characteristics of (Ni/Au)/Al0.3Ga0.7N/AlN/GaN heterostructures were investigated by considering the effect of series resistance (Rs) and interface states Nss in a wide temperature range (79-395 K). Our experimental results show that both Rs and Nss were found to be strongly functional with temperature and bias voltage. Therefore, they affect the (C-V) and (G/w-V) characteristics. The values of capacitance give two peaks at high temperatures, and a crossing at a certain bias voltage point (∼3.5 V). The first capacitance peaks are located in the forward bias region (∼0.1 V) at a low temperature. However, from 295 K the second capacitance peaks appear and then shift towards the reverse bias region that is located at ∼−4.5 V with increasing temperature. Such behavior, as demonstrated by these anomalous peaks, can be attributed to the thermal restructuring and reordering of the interface states. The capacitance (Cm) and conductance (G/w-V) values that were measured under both reverse and forward bias were corrected for the effect of series resistance in order to obtain the real diode capacitance and conductance. The density of Nss, depending on the temperature, was determined from the (C-V) and (G/w-V) data using the Hill-Coleman Method. 相似文献
45.
模拟计算了光的入射角度与反射率的关系,当光的入射角度大于23°时,发生全反射,无论是否在器件表面生长增透膜,这时的光都无法从器件顶部出射表面提取出来。研究了使用等离子体增强化学气相沉积法(PECVD)在已经制备了n电极和p电极的GaN基LED上制备钝化膜,分析了SiON和SiN_x膜沉积对于器件的光输出功率的影响。通过实验证明,在器件上沉积SiON后,光输出功率增加。 相似文献
46.
S. Kerboeuf M. Bettiati J. L. Gentner C. Belouet J. Perrière J. Jimenez E. Martin 《Journal of Electronic Materials》1999,28(2):83-90
It is reported on the passivation of the mirror facets, opened in the air, of ridge waveguide InGaAs/GaAs/AlGaAs single quantum
well (λ=980 nm) laser diodes. The passivation concept consists of two steps, namely, oxide removal by irradiation of the mirror facets
with a pulsed KrF laser, immediately followed by the deposition of a thin silicon layer. The experimental arrangement (the
process operation and the aging behavior-resistance to catastrophic optical damage) of the lasers thus treated are described.
The structural modification of the laser facets, as probed by micro-Raman spectroscopy and Rutherford backscattering spectroscopy,
and the calibration technique used to assess the rate of oxide removal are also presented. 相似文献
47.
Jingjing Tian Jing Wang Qifan Xue Tianqi Niu Lei Yan Zonglong Zhu Ning Li Christoph J. Brabec Hin‐Lap Yip Yong Cao 《Advanced functional materials》2020,30(28)
Cesium‐based inorganic perovskites have recently attracted great research focus due to their excellent optoelectronic properties and thermal stability. However, the operational instability of all‐inorganic perovskites is still a main hindrance for the commercialization. Herein, a facile approach is reported to simultaneously enhance both the efficiency and long‐term stability for all‐inorganic CsPbI2.5Br0.5 perovskite solar cells via inducing excess lead iodide (PbI2) into the precursors. Comprehensive film and device characterizations are conducted to study the influences of excess PbI2 on the crystal quality, passivation effect, charge dynamics, and photovoltaic performance. It is found that excess PbI2 improves the crystallization process, producing high‐quality CsPbI2.5Br0.5 films with enlarged grain sizes, enhanced crystal orientation, and unchanged phase composition. The residual PbI2 at the grain boundaries also provides a passivation effect, which improves the optoelectronic properties and charge collection property in optimized devices, leading to a power conversion efficiency up to 17.1% with a high open‐circuit voltage of 1.25 V. More importantly, a remarkable long‐term operational stability is also achieved for the optimized CsPbI2.5Br0.5 solar cells, with less than 24% degradation drop at the maximum power point under continuous illumination for 420 h. 相似文献
48.
Kai Wang Jiang Liu Jun Yin Erkan Aydin George T. Harrison Wenzhu Liu Shanyong Chen Omar F. Mohammed Stefaan De Wolf 《Advanced functional materials》2020,30(35)
Defects at the surface and grain boundaries of metal–halide perovskite films lead to performance losses of perovskite solar cells (PSCs). Here, organic cyano‐based π‐conjugated molecules composed of indacenodithieno[3,2‐b]thiophene (IDTT) are reported and it is found that their cyano group can effectively passivate such defects. To achieve a homogeneous distribution, these molecules are dissolved in the antisolvent, used to initiate the perovskite crystallization. It is found that these molecules are self‐anchored at the grain boundaries due to their strong binding to undercoordinated Pb2+. On a device level, this passivation scheme enhances the charge separation and transport at the grain boundaries due to the well‐matched energetic levels between the passivant and the perovskite. Consequently, these benefits contribute directly to the achievement of power conversion efficiencies as high as 21.2%, as well as the improved environmental and thermal stability of the PSCs. The surface treatment provides a new strategy to simultaneously passivate defects and enhance charge extraction/transport at the device interface by manipulating the anchoring groups of the molecules. 相似文献
49.
Hg1-xCdxTe光伏探测器的表面漏电流机制及其钝化 总被引:2,自引:0,他引:2
表面漏电流能对Hg1-xCdxTe光伏探测器性能产生很大的影响,因此选择合适的钝化工艺尤其重要。本文主要论述了Hg1-xCdxTe光伏探测器表面漏电流机制及其钝化技术的发展状况。 相似文献
50.
Ho-Young Cha Y. C. Choi R. M. Thompson V. Kaper J. R. Shealy L. F. Eastman M. G. Spencer 《Journal of Electronic Materials》2004,33(8):908-911
The SiC metal-semiconductor field-effect transistors (MESFETs) have been reported to have current instability and strong dispersion
caused by trapping phenomena at the surface and in the substrate, which degrade direct-current (DC) and radio-frequency (RF)
performance. This paper illustrates the change in electrical characteristics of SiC MESFETs after Si3N4 passivation. Because of a reduction of surface trapping effects, Si3N4 passivation can diminish current collapse under pulsed DC conditions, increasing the RF power performance. The reduction
of surface trapping effects is verified by the change in the ratio of the drain current to the gate current under pinch-off
conditions. 相似文献