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101.
Physical modeling of direct current and radio frequency characteristics for In P-based InAlAs/InGaAs HEMTs 下载免费PDF全文
Direct current(DC) and radio frequency(RF) performances of InP-based high electron mobility transistors(HEMTs)are investigated by Sentaurus TCAD. The physical models including hydrodynamic transport model, Shockley–Read–Hall recombination, Auger recombination, radiative recombination, density gradient model and high field-dependent mobility are used to characterize the devices. The simulated results and measured results about DC and RF performances are compared, showing that they are well matched. However, the slight differences in channel current and pinch-off voltage may be accounted for by the surface defects resulting from oxidized InAlAs material in the gate-recess region. Moreover,the simulated frequency characteristics can be extrapolated beyond the test equipment limitation of 40 GHz, which gives a more accurate maximum oscillation frequency( f_(max)) of 385 GHz. 相似文献
102.
可靠性问题是GaN基HEMT器件走向实用化的关键,逆压电效应导致器件退化是近年来比较引人瞩目的理论之一。对于GaN基HEMT器件,当其承受外加电场时,由于逆压电效应,电场最终转化成弹性势能。当电场足够大,突破势垒层材料所能承受的临界弹性势能,势垒层材料就会发生松弛。根据逆压电效应导致器件退化机理,从弹性势能的角度出发,对低Al组分AlGaN势垒层、InAlN势垒层和AlGaN背势垒等三种结构进行理论分析。分析表明,三种结构均能较大程度地改善GaN基HEMT器件的抗逆压电能力,从而提高器件可靠性。 相似文献
103.
研究了AlGaN/GaN 高电子迁移率晶体管(HEMT)的质子辐照效应. 在3 MeV质子辐照下, 当辐照剂量达到1× 1015 protons/cm2时, 漏极饱和电流下降了20%, 最大跨导降低了5%. 随着剂量增加, 阈值电压向正向漂移, 栅泄露电流增加. 在相同辐照剂量下, 1.8 MeV质子辐照要比3 MeV质子辐照退化严重. 从SRIM软件仿真中得到不同能量质子在AlGaN/GaN异质结中的辐射损伤区, 以及在一定深度形成的空位密度. 结合变频C-V测试结果进行分析, 表明了质子辐照引入空位缺陷可能是AlGaN/GaN HEMT器件电学特性退化的主要原因. 相似文献
104.
为了缓解AlGaN/GaNhighelectronmobilitytransistors(HEMT)器件n型GaN缓冲层高的泄漏电流,本文提出了具有氟离子注入新型Al0.25Ga0.75N/GaNHEMT器件新结构.首先分析得出n型GaN缓冲层没有受主型陷阱时,器件输出特性为欧姆特性,这样就从理论和仿真方面解释了文献生长GaN缓冲层掺杂Fe,Mg等离子的原因.利用器件输出特性分别分析了栅边缘有和没有低掺杂漏极时,氟离子分别注入源区、栅极区域和漏区的情况,得出当氟离子注入源区时,形成的受主型陷阱能有效俘获源极发射的电子而减小GaN缓冲层的泄漏电流,击穿电压达到262v通过减小GaN缓冲层体泄漏电流,提高器件击穿电压,设计具有一定输出功率新型A1GaN/GaNHEMT提供了科学依据. 相似文献
105.
本文利用高波数分辨率的显微喇曼方法测量了AlGaN/GaN 高电子迁移率晶体管(HEMT)的沟道温度。利用显微喇曼系统JYT-64000测量了GaN材料E2模的喇曼声子频率的温度特性。通过洛仑兹拟合方法,喇曼声子频率的实际测量不确定度为?0.035cm-1, 对应于GaN材料温度精度为?3.2℃,为国际所见报道的最高水平。测得的AlGaN/GaN HEMT样品的沟道-管壳热阻为22.8℃/W,与三维热传导模型的仿真结果吻合良好。给出了由显微喇曼方法、脉冲电学法及红外热像法测量出的沟道温度差别的定量分析。 相似文献
106.
A reduced surface electric field in AlGaN/GaN high electron mobility transistor (HEMT) is investigated by employing a localized Mg-doped layer under the two-dimensional electron gas (2-DEG) channel as an electric field shaping layer. The electric field strength around the gate edge is effectively relieved and the surface electric field is distributed evenly as compared with those of HEMTs with conventional source-connected field plate and double field plate structures with the same device physical dimensions. Compared with the HEMTs with conventional source-connected field plate and double field plate, the HEMT with Mg-doped layer also shows that the breakdown location shifts from the surface of the gate edge to the bulk Mg-doped layer edge. By optimizing both the length of Mg-doped layer, Lm, and the doping concentration, a 5.5 times and 3 times the reduction in the peak electric field near the drain side gate edge is observed as compared with those of the HEMTs with source-connected field plate structure and double field plate structure, respectively. In a device with VGS=-5 V, Lm=1.5 μm, a peak Mg doping concentration of 8× 1017 cm-3 and a drift region length of 10 μm, the breakdown voltage is observed to increase from 560 V in a conventional device without field plate structure to over 900 V without any area overhead penalty. 相似文献
107.
本文提出了一种考虑这冲效应的HEMT器件静态和小信号解析物理模型。通过对栅极下面道中造近源端附近的电场采用弱强梯场近似,提出了一个半经验的速度过冲模型,在非线性电荷控制模型的基础上述导出了基于物理参数的HEMT器件电流-电压特性和小等效电路参数的解析表达式。实际计算结果与测得数据比较表明,本模型具有比较高的精度。 相似文献
108.
Mohamed Kameche 《International Journal of Infrared and Millimeter Waves》2006,27(8):1133-1144
The origins of HEMT distortion in passive control applications as SPST switch are presented in this paper. Also, this paper
describes the change of the AlGaN/GaN HEMT switch distortion properties (second-and third distortion intercept points) over
a wide range of temperature. The results indicate that the change in second-and third-order distortion intercept points is
smaller (about 2dBm) over a wide range of temperature from −50 to +300°C. A comparison of the GaN-based HEMT switch with InP-and
GaAs-HEMT switches shows that the GaN technology generates lower distortion than its InP and GaAs technologies counterpart. 相似文献
109.
《International Journal of Infrared and Millimeter Waves》1997,18(1):85-99
A two-stage 8–12 GHz (X-band) cryogenically-cooled Low-Noise Amplifier (LNA) has been developed with a commercial pseudomorphic
HEMT on AsGa substrate. In a first step, different commercial transistors have been fully characterized from 300 K to 20 K
using a new method to measure the four noise parameters. Preliminary results have allowed the selection of the best device.
This enabled the design of the two-stage LNA with the help of a microwave CAD software.
In a second step, the LNA has been characterized at 300 K, 30 K and 4 K. As the physical temperature decreased from 300 K
to 30 K, the LNA exhibited an average gain increase of 2 dB and as much as a fourfold reduction of noise temperature. A noise
figure of 22.5 K and a gain of 23 dB have been achieved at 30 K around 10 GHz. The noise temperature has been furthermore
reduced to 20 K by cooling the amplifier at the liquid helium temperature (4.2 K). Different methods to measure the noise
characteristics of the amplifier are widely developed in this paper. 相似文献
110.
Ka波段HEMT噪声系数测试 总被引:1,自引:1,他引:0
介绍了Ka波段HEMT及其单片低噪声放大器的测试方法,着重分析了低频振荡原因和抑制方法,探讨了毫米波电路测试的特点,最后给出了测试结果。 相似文献