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1.
Byoung-Gue Min Jong-Min Lee Hyung Sup Yoon Woo-Jin Chang Jong-Yul Park Dong Min Kang Sung-Jae Chang Hyun-Wook Jung 《ETRI Journal》2023,45(1):171-179
We have developed an InAlAs/InGaAs metamorphic high electron mobility transistor device fabrication process where the gate length can be tuned within the range of 0.13 μm–0.16 μm to suit the intended application. The core processes are a two-step electron-beam lithography process using a three-layer resist and gate recess etching process using citric acid. An electron-beam lithography process was developed to fabricate a T-shaped gate electrode with a fine gate foot and a relatively large gate head. This was realized through the use of three-layered resist and two-step electron beam exposure and development. Citric acid-based gate recess etching is a wet etching, so it is very important to secure etching uniformity and process reproducibility. The device layout was designed by considering the electrochemical reaction involved in recess etching, and a reproducible gate recess etching process was developed by finding optimized etching conditions. Using the developed gate electrode process technology, we were able to successfully manufacture various monolithic microwave integrated circuits, including low noise amplifiers that can be used in the 28 GHz to 94 GHz frequency range. 相似文献
2.
我们研究了非对称In0.53Ga0.47As/In0.52Al0.48As量子阱中二维电子气的磁输运性质,所测量的样品的径向磁阻Rxx的Shubinikov-de Haas振荡没有呈现出拍频的特征。通过测量样品的弱局域效应提取了其零场自旋分裂能并通过对自旋分裂的Rxx双峰间距随倾斜角度theta的依赖关系的拟合提取了高场下的有效g因子。样品的Dingle plot图呈现非线性和特征,这可以归因于来自样品衬底附近的掺杂Be原子的长程势散射效应。 相似文献
3.
利用变温Hall测量研究了重掺杂InGaAs/InAlAs单量子阱中二维电子气,发现在量子阱中由于存在电子对称态和反对称态导致纵向电阻出现拍频现象。通过分析拍频节点位置,得到电子对称态和反对称态之间的能级间距为4meV。此外,通过迁移率谱方法和多载流子拟合过程研究了不同迁移率电子的浓度和迁移率随温度的变化关系。 相似文献
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We have investigated, as a function of indium content x, the galvanomagnetic and Shubnikov de Haas (SdH) properties of two-dimensional
electron gases (2DEG) formed at lattice matched, strain relaxed InAlAs/InGaAs heterojunctions. These were grown by molecular
beam epitaxy on GaAs misoriented substrates with a two degree offcut toward the nearest (110) plane. Variable temperature
resistivity and Hall measurements indicate an increase in the electron sheet density ns from 0.78×1012cm−2 for x=0.15 to 1.80×1012 cm−2 for x=0.40 at 300K, and from 0.75×1012cm−2 to 1.67×1012cm−2 at T=1.6K. The room temperature electron mobility, measured along the in plane [110], direction is independent of indium
content and equals approximately 9500 cm2/Vs. For T<50K, the mobility is independent of temperature decreasing with increasing x from 82000 cm2/Vs for x=0.15 to 33000 cm2/Vs for x=0.40. The ratios (τt/τq) at 1.6K between the electron relaxation time τt and the single particle relaxation time τq, for the strain relaxed specimens, as well as for pseudomorphically strained Al0.35Ga0.65As/In0.15Ga0.85As structures grown on GaAs substrates, and In0.52Al0.48As/In0.53Ga0.47As heterostructures grown lattice matched on InP substrates. Such a study indicates the presence of inhomogeneities in the
2DEGs of the strain relaxed specimens which appear to be related to the process of strain relaxation. Such inhomogeneities,
however, have little effect on the electron relaxation time τt which, at low temperatures, is limited principally by alloy scattering. 相似文献
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采用普通接触曝光研制成栅长为0 .2 5 μm的Ga As基In Al As/ In Ga As变组分高电子迁移率晶体管(MHEMT) ,测得其跨导为5 2 2 m S/ m m,沟道电流密度达4 90 m A/ mm,截止频率为75 GHz,比同样工艺条件下Ga As基In Ga P/ In Ga As PHEMT的性能有很大的提高.对该器件工艺及结果进行了分析,提取了器件的交流小信号等效电路模型参数,并提出了进一步得到高稳定性、高性能器件的方法. 相似文献
10.
Matthew Seaford Scott Massie Dave Hartzell Glenn Martin Warren Wu John Tucker Lester Eastman 《Journal of Electronic Materials》1997,26(1):30-33
InGaAs/InAlAs double-doped double-strained modulation-doped field-effect transistors OD-SMODFETs)1 were grown by solid source molecular beam epitaxy. The structures were characterized using high resolution x-ray diffraction, Hall effect, and cross-sectional scanning tunneling microscopy. A record two-dimensional electron gas (2DEG) sheet density of 8.5 × 1012/cm2 and 8.1 × 1012/cm2 for 300 and 77K, respectively, was achieved. The mobility was 6500 and 12000 cm2/ Vs for 300 and 77K, respectively. To the author’s knowledge,2 the previous record 2DEG result was 6.58 × 1012/cm2. The electron mobility was limited by alloy scattering and interface roughness caused by the presence of “clustering.” Using cross-sectional scanning tunneling microscopy to verify the presence of these clusters, we have the first images of the lattice matched InAlAs (spacer)-InGaAs (quantum well) interface. These images reveal clusters that have approximate spherical or cylindrical shapes with equivalent cubic dimensions ranging from 25 to 45Å. 相似文献