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1.
自1977年以来,为了摸索离子注入半导体的新退火方法,各国学者进行了大量的研究工作。这种努力是从激光退火的研究开始的。激光与半导体材料相互作用的研究,已派生出若干很有生命力的应用项目,其中,快速热退火、SOI(Semiconductor on Insulator)技术等已显示了重要的应用前景,并正在走向实用化。  相似文献   
2.
Bulk indium phosphide crystals have been prepared by zone melting with dislocation densities 104 ≤ Nd ≤ 105 cm-2. The residual impurity level in nominally undoped crystals and the dopant distribution in Cd-, Sn- and Ge-doped zone melted ingots, as revealed by spark source mass spectrometric analyses, indicate a strong interaction between segregation at the solid/liquid interface and vapor transport. The effective distribution coefficients for Sn and Ge in zone melted InP are ke(Sn) = 0.3 and ke(Ge) = 0.4. The free electron concentration measured in the middle section of nominally undoped ingots is ND-NA = 1.9 × 1015 cm-3 corresponding to a Hall mobility Μe = 3263 cm2V-1sec-l.  相似文献   
3.
Tertiarybutylarsine (TBA) and teriarybutylphosphine (TBP) are liquid organometallic sources that are a safer alternative to arsine and phosphine. In this work, we have grown high-quality In0.53Ga0.47As/InP quantum wells at a temperature of 590° with TBA and TBP partial pressures of 0.4 and 2.5 Torr, respectively. A low-temperature photoluminescence study indicated optimized column V growth interruption times of 0.5 s for In0.53Ga0.47As wells with InP barriers. Using the optimized growth conditions, we have obtained lattice matched In0.53Ga0.47As/InxGa1-xAsyP1-x single quantum-well lasers emitting at 1.55 μm. Broad-area devices with a length of 3.5 mm exhibit a low threshold current density of 220A/cm2. Broad-area lasers containing four quantum wells had a threshold current density of 300A/cm2 for a 3.0 mm cavity length and CW powers of 40 mW per facet for an as-cleaved 4 × 750 μm device.  相似文献   
4.
Low-bandgap, lattice-mismatched GaxIn1−xAs (GaInAs) grown using InAsyP1−y (InAsP) compositional-step grades on InP is a primary choice for lightabsorbing, active layers in high-efficiency thermophotovoltaic (TPV) devices. The GaInAs/InAsP double heterostructures (DHs) show exceptional minority carrier lifetimes of up to several microseconds. We have performed a characterization survey of 0.4–0.6-eV GaInAs/InAsP DHs using a variety of techniques, including transmission electron microscopy (TEM). Dislocations are rarely observed to thread into the GaInAs active layers from the InAsP buffer layers that terminate the graded regions. Nearly complete strain relaxation occurs in buried regions of the InAsP grades. The buffer-layer strain prior to deposition of the active layer is virtually independent of the net misfit. Foreknowledge of this buffer-layer strain is essential to correctly lattice match the buffer to the GaInAs active layer.  相似文献   
5.
Ultra-high-vacuum chemical vapor deposition (UHV/CVD) system displays excellent performance for the growth of high-quality SiGe film. Investigations have shown that have shown that SiGe film grown by this system has high quality. A 10-finger SiGe hetero-junction bipolar transistor (HBT) device displayed good electrical performance. The current gain was about 500, and the fT was 5.4 GHz with fmax 7.5 GHz under VCB=3 V, IC=10 mA. This article is based on a presentation in “The 7th Korea-China Workshop on Advanced Materials” organized by the Korea-China Advanced Materials Cooperation Center and the China-Korea Advanced Materials Cooperation Center, held at Ramada Plaza Jeju Hotel, Jeju Island, Korea on August 24–27, 2003.  相似文献   
6.
束维宏 《安徽建筑》2006,13(5):92-92,94
根据作者多年来的国际施工经验,并结合近年来国内外高层结构核心筒的施工方案,综合介绍与核心筒相接的楼梯、楼板的施工技术措施,重点介绍了国外工程H BT预埋方法在核心筒中应用的新方法。  相似文献   
7.
A 1.4-μm thick InGaAs layer exhibiting an x-ray diffraction linewidth of 18 arcs has been grown on an InP substrate. This is the best crystalline perfection ever reported for InGaAs, as far as the author is aware. The effect of gas composition on lattice mismatch has been investigated for InGaAs layers grown under a variety of conditions. An empirical equation has been developed which relates lattice mismatch(Δa/a) to metals ratio, mole fraction of AsH3 and mole fraction of HC1. Values of(Δa/a) calculated using this equation are in good agreement with experiment. The metals ratio for lattice match is shown to vary linearly with the growth rate. This observation is shown to be consistent with mass transfer limitation in the gas phase. As a further consequence, relationships between layer thickness uniformity and lattice mismatch uniformity and between growth rate and gas composition are derived.  相似文献   
8.
Nanostructured porous InP samples were prepared by electrochemical anodic dissolution of InP for various current densities and etching periods. The samples were characterized by SEM and photoluminescence (PL) where a blue shift was observed in PL. Thermal properties studied by photoacoustic (PA) spectroscopy revealed one order decrease in thermal conductivity of porous InP compared to the bulk. Further it is shown that the thermal conductivity of porous InP decreases with decrease in size of the particles.  相似文献   
9.
Electrical measurements have been reported sandwich device fabricated from DNA molecular film located between Al and p-type InP inorganic semiconductor. We have observed that DNA-based this structure shows an excellent rectifying behavior, and that the DNA film increases the effective barrier height by influencing the space charge region of InP. We have also evaluated electrical characteristics of the DNA-based device in a wide temperature range.  相似文献   
10.
研究了0.18 μm SiGe BiCMOS中的核心器件SiGe HBT的关键制造工艺,包括集电极的形成、SiGe基区的淀积、发射极窗口的形成、发射极多晶的淀积、深孔刻蚀等,指出了这些制造工艺的难点和问题,提出了解决办法,并报导了解决相关难题的实验结果.  相似文献   
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