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排序方式: 共有111条查询结果,搜索用时 46 毫秒
1.
J. M. Ballingall P. Ho J. Mazurowski L. Lester K. C. Hwang J. Sutliff S. Gupta J. Whitaker 《Journal of Electronic Materials》1993,22(12):1471-1475
InxGa1−xAs (x=0.25–0.35) grown at low temperature on GaAs by molecular beam epitaxy is characterized by Hall effect, transmission
electron microscopy, and ultrafast optical testing. As with low temperature (LT) GaAs, the resistivity is generally higher
after a brief anneal at 600°C. High-resolution transmission electron microscopy shows all the as-grown epilayers to be heavily
dislocated due to the large lattice mismatch (2–3%). When the layers are annealed, in addition to the dislocations, precipitates
are also generally observed. As with LT-GaAs, the lifetime shortens as growth temperature is reduced through the range 300–120°C;
also, the lifetime in LT-InxGa1−xAs is generally shorter in as-grown samples relative to annealed samples. Metal-semiconductor-metal photodetectors fabricated
on the material exhibit response times of 1–2 picoseconds, comparable to results reported on GaAs grown at low temperature,
and the fastest ever reported in the wavelength range of 1.0–1.3 μm. 相似文献
2.
Stanislav V. Averin Petr I. Kuznetzov Victor A. Zhitov Nikolai V. Alkeev 《Optical and Quantum Electronics》2007,39(3):181-192
Solar-blind MSM photodetectors based on the AlGaN heterostructures have been fabricated and investigated. The influence of
material properties on device parameters is discussed. Effect of different buffer layers on the detector performances has
been examined. Detectors exhibit low dark currents and high sensitivity within the range of 250–290 nm. Effect of optical
excitation energy on GaN-based MSM-detector performance is analyzed and discussed. At high excitation level the detector speed
of response is limited by the field screening caused by the space-charge of the holes. The impulse response of GaN-based MSM-detector
is compared favorably with GaAs MSM-device. 相似文献
3.
MSM结构硅光探测器 总被引:1,自引:0,他引:1
采用 MSM 双肖特基势垒结构制作的硅光电二极管,在0.2~1.10μm波长范围内具有高的响应度。这种结构还可以构成横向光晶体管,共发射极电流增益为2~4倍。实验表明,MSM 结构是改善硅光电探测器光谱响应的良好结构。 相似文献
4.
Nitride-Based ultraviolet metal-semiconductor-metal photodetectors with a low-temperature GaN layer 总被引:1,自引:0,他引:1
J. K. Sheu C. J. Kao M. L. Lee W. C. Lai L. S. Yeh G. C. Chi S. J. Chang Y. K. Su J. M. Tsai 《Journal of Electronic Materials》2003,32(5):400-402
The GaN metal-semiconductor-metal (MSM) ultraviolet (UV) photodetectors with a low-temperature (LT)-GaN layer have been demonstrated.
It was found that we could achieve a two orders of magnitude smaller, photodetector-dark current by introducing a LT-GaN layer,
which could be attributed to the larger Schottky-barrier height between the Ni/Au metal contact and the LT-GaN layer. It was
also found that photodetectors with the LT-GaN layer could provide a larger photocurrent to dark-current contrast ratio and
a larger UV-to-visible rejection ratio. The maximum responsivity was found to be 3.3 A/W and 0.13 A/W when the photodetector
with a LT-GaN layer was biased at 5 V and 1 V, respectively. 相似文献
5.
MSM9811是OKI公司生产的4通道混合语音合成芯片。他可以选择直接8b PCM,非线性的8b PCM,4bADCPCM和4b ADPCM2语音格式并且提供了两通道的立体音输出及音量控制。介绍了MSM9811语音芯片的引脚功能、接口命令以及具体使用方法。同时给出了用AT89C52与MSM9811构成的语音系统的硬件设计和相应的软件编程。 相似文献
6.
MSM9841是日本OKI(冲)电气半导体公司研制的单声道/立体声语音控制处理大规模集成芯片。文中介绍了该芯片的结构、特点、工作原理及其在数字语音录放机中的应用。 相似文献
7.
在Si衬底上磁控溅射制备AlxZn1-xO(AZO)合金薄膜,在其上真空蒸发Ni/Au叉指电极获得金属-半导体-金属(MSM)结构光电探测器.采用UV-Vis-Nir分光光度计测量AZO系列薄膜的光吸收特性,观察到AZO 合金薄膜的光学吸收带边随Al含量增加明显蓝移.测试AZO探测器的电流电压特性、时间特性和响应光谱发... 相似文献
8.
9.
Current transport in molecular beam epitaxy (MBE) GaAs grown at low and intermediate growth temperatures is strongly affected
by defects. A model is developed here that shows that tunneling assisted by defect states can dominate, at some bias ranges,
current transport in Schottky contacts to unannealed GaAs material grown at the intermediate temperature range of about 400°C.
The deep defect states are modeled by quantum wells which trap electrons emitted from the cathode before re-emission to semiconductor.
Comparison of theory with experimental data shows defect states of energies about 0.5 eVbelow conduction band to provide the
best fit to data. This suggests that arsenic interstitials are likely to mediate this conduction. Comparison is also made
between as-grown material and GaAs grown at the same temperature but annealed at 600°C. It is suggested that reduction of
these defects by thermal annealing can explain lower current conduction at high biases in the annealed device as well as higher
current conduction at low biases due to higher lifetime. Quenching of current by light in the as-grown material can also be
explained based on occupancy of trap states. Identification of this mechanism can lead to its utilization in making ohmic
contacts, or its elimination by growing tunneling barrier layers. 相似文献
10.
Michael F. Zimmer 《Journal of statistical physics》1993,73(3-4):751-764
The fluctuation-dissipation theorem is not expected to hold for systems that either violate detailed balance or have time-dependent or nonpotential forces. Therefore the relation between response and correlation functions should have contributions due to the nonequilibrium nature. An explicit formula for such a contribution is calculated, which in the present derivation appears as a historydependent term. These relations are the Ward-Takahashi identities of a supersymmetric formulation of the Langevin models, and the new term results from a broken supersymmetry. 相似文献