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排序方式: 共有110条查询结果,搜索用时 890 毫秒
1.
J. Hong E. S. Lambers C. R. Abernathy S. J. Pearton R. J. Shul W. S. Hobson 《Journal of Electronic Materials》1998,27(3):132-137
Dry etching of InGaP, AlInP, and AlGaP in inductively coupled plasmas (ICP) is reported as a function of plasma chemistry (BCl3 or Cl2, with additives of Ar, N2, or H2), source power, radio frequency chuck power, and pressure. Smooth anisotropic pattern transfer at peak etch rates of 1000–2000Å·min?1 is obtained at low DC self-biases (?100V dc) and pressures (2 mTorr). The etch mechanism is characterized by a trade-off between supplying sufficient active chloride species to the surface to produce a strong chemical enhancement of the etch rate, and the efficient removal of the chlorinated etch products before a thick selvedge layer is formed. Cl2 produces smooth surfaces over a wider range of conditions than does BCl3. 相似文献
2.
Berg Alexander Caroff Philippe Shahid Naeem Lockrey Mark N. Yuan Xiaoming Borgström Magnus T. Tan Hark Hoe Jagadish Chennupati 《Nano Research》2017,10(2):672-682
Ternary Ⅲ-Ⅴ nanowires (NWs) cover a wide range of wavelengths in the solar spectrum and would greatly benefit from being synthesized as position-controlled arrays for improved vertical yield,reprodudbility,and tunable optical absorption.Here,we report on successful selective-area epitaxy of metal-particle-free vertical InxGa1-xP NW arrays using metal-organic vapor phase epitaxy and detail their optical properties.A systematic growth study establishes the range of suitable growth parameters to obtain uniform NW growth over a large array.The optical properties of the NWs were characterized by room-temperature cathodoluminescence spectroscopy.Tunability of the emission wavelength from 870 nm to approximately 800 nm was achieved.Transmission electron microscopy and energy dispersive X-ray measurements performed on crosssection samples revealed a pure wurtzite crystal structure with very few stacking faults and a slight composition gradient along the NW growth axis. 相似文献
3.
自对准InGaP/GaAs HBT单片集成跨阻放大器 总被引:2,自引:1,他引:2
对自对准 In Ga P/ Ga As HBT单片集成跨阻放大器进行了研究 .采用发射极金属做腐蚀掩膜并利用 Ga As腐蚀各向异性的特点来完成 BE金属自对准工艺 ,最终制作出的器件平均阈值电压为 1.15 V,单指管子电流增益为5 0 ,发射极面积 4μm× 14μm的单管在 IB=2 0 0μA和 VCE=2 V偏压条件下截止频率达到了 4 0 GHz.设计并制作了直接反馈和 CE- CC- CC两种单片集成跨阻放大器电路 ,测量得到的跨阻增益在 3d B带宽频率时分别为 5 0 .6 d BΩ和 4 5 .1d BΩ ,3d B带宽分别为 2 .7GHz和 2 .5 GHz,电路最小噪声系数分别为 2 .8d B和 3.2 d B. 相似文献
4.
We report the Schottky performance and thermal reliability of a wide bandgap InGaP layer in contact with a Cu/Au metallic
system. An effective Schottky barrier height of 0.97 eV and an ideality factor of 1.21 can be achieved. The thermal reliability
of the resultant Schottky barrier diodes was analyzed using Auger electron spectroscopy and atomic force microscopy. The thermal
reliability could be main tained up to 450°C. The failure mechanism was attributable to the decomposition of the InGaP layer
and the interdiffusion of the chemical elements at higher temperature. Insensitive photoresponsivity with the in cident optical
power was found for the resultant Au/Cu-metal-semiconductor-metalphotodetectors (MSM-PDs). According to the measured temporal
response of the Au/Cu-MSM-PDs, the operation frequency could be above 10 GHz. 相似文献
5.
6.
K. A. Jones R. T. Lareau T. Monahan J. R. Flemish R. L. Pfeffer R. E. Sherriff C. W. Litton R. L. Jones C. E. Stutz D. C. Look 《Journal of Electronic Materials》1995,24(11):1641-1648
Symmetric δ-doped InGaP and AlGaAs PHEMT structures have been grown by organometallic vapor phase epitaxy with properties
that approach those of MBE grown AlGaAs structures. The 300 and 77K carrier concentrations for the InGaP PHEMT were 2.72 and
2.56 × 1012 cm2
−2 and the mobilities were 5,920 and 22,000 cm2
2/V.s. These excellent values suggest that problems associated with switching the anion at the channel heterojunction have
been overcome. The corresponding values for the AlGaAs PHEMT were 2.51 and 2.19 × 1012 cm2
−2 and 6,500 and 20,400 cm2/V.s. The uniformity in the indium concentration in the InGaAs layer as determined by photoluminescence, photoreflection,
double crystal x-ray diffraction, and Rutherford backscattering was found to be good, but the percent In in the AlGaAs pseudo-morphic
high electron mobility transistor (PHEMT) was less than that in the InGaP PHEMT even though the programmed values were the
same. The uniformity in the doping distribution as determined by secondary ion mass spectroscopy and electrochemical capacitance-voltage
measurements was found to be good, but it decreased with distance from the center of the susceptor. Also, most of the dopants
in the δ-doped InGaP and AlGaAs layers were activated. 相似文献
7.
介绍了一种由商用InGaP/GaAs异质结双极晶体管工艺制成、基于负阻原理的单片压控振荡器,此电路定位于5GHz频段下的无线应用.在实际使用中,除了旁路和去耦电容外,无需外接其他外部元件.测试得到的输出频率范围超过300MHz,为4.17~4.56GHz,与仿真结果非常吻合;相位噪声为-112dBc/Hz@1MHz;在3.3V电源电压下,其核心部分的直流功耗为15.5mW,输出功率为0~2dBm.为了与其他振荡器比较,还通过计算得到了相位噪声优值,约为-173.2dBc/Hz.同时,还讨论了负阻振荡器的原理和设计方法. 相似文献
8.
Dong‐Won Kang Yuki Takiguchi Porponth Sichanugrist Makoto Konagai 《Progress in Photovoltaics: Research and Applications》2016,24(7):1016-1023
In this work, we practically demonstrated spectrum‐splitting approach for advances in efficiency of photovoltaic cells. Firstly, a‐Si:H//c‐Si 2‐junction configuration was designed, which exhibited 24.4% efficiency with the spectrum splitting at 620 nm. Then, we improved the top cell property by employing InGaP cells instead of the a‐Si:H, resulting in an achievement of efficiency about 28.8%. In addition, we constructed 3‐junction spectrum‐splitting system with two optical splitters, and GaAs solar cells as middle cell. This InGaP//GaAs//c‐Si architecture was found to deliver 30.9% conversion efficiency. Our splitting system includes convex lenses for light concentration about 10 suns, which provided concentrated efficiency exceeding 33.0%. These results suggest that our demonstration of 3‐junction spectrum‐splitting approach can be a promising candidate for highly efficient photovoltaic technologies. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
9.
通过分析InGaP/GsAsHBT器件的热学和电学特点,结合HBT大功率放大器芯片在技术性能、稳定性、可靠性及尺寸等方面的要求,通过优化设计HBT功率器件单元和匹配电路,开发了一个大功率、高效率、小尺寸的ISM波段功率放大器单片集成电路。该三级放大器的各级器件单元的发射极面积分别为320μm2,1280μm2,5760μm2,芯片内部包括了输入、输出50Ω匹配电路,面积仅为1.9mm×2.1mm。放大器采用5V单电源供电,在2.4~2.5GHz频率范围内线性增益为27dB,2dB增益压缩点输出饱和功率达到37dBm,功率附加效率为46%。 相似文献
10.
对InGaP/GaAs外延材料合金有序度表征方法进行了综述,指出从结构X-Ray)光学性能摘要(透射电子显微镜,、(光、电学性能三方面度量InGaP/GaAs材料的有序度。 相似文献