Si^＋,As^＋双离子注放半绝缘GaAs的无包封快速热退火技术的研究

本文采用清华大学ＱＳＷ－３０７５快速热处理设备对Ｓｉ＾＋，Ａｓ＾＋双离子注入半绝缘ＧａＡｓ进行了快速热退火研究。结果表明，在适当条件下退火，注入杂质有高的激活效率，并且杂几乎没有因高温退火引起的扩散再分布，保留了原有的注入分布。在加热位置降温可消除注入晶片滑移的产生。     

离子注入半绝缘GaAs电激活效率与电激活均匀性的研究

研究了Ｓｉ＾＋和Ｓｉ＾＋／Ａｓ＾＋注入到Ｈｏｒｉｚｏｎｔａｌ Ｂｒｉｄｇｍａｎ（ＨＢ）和Ｌｉｑｕｉｄ Ｅｎｃａｐｓｕｌａｔｅｄ Ｃｚｏｃｈｒａｌｓｋｉ（ＬＥＣ）方法制备的半绝缘ＧａＡｓ衬底电激活效率与均匀性。结果发现：在相同条件下（注入与退火）,不同生长方法的半绝缘ＧａＡｓ衬底电激活不同,通常电激活ＨＢ〉ＬＥＣ,ＨＢ ＳＩ－－ＧａＡｓ（Ｃｒ）（１００）Ａ面〉（１００）Ｂ面,Ｓｉ＾＋／Ａｓ＾＋双离子     

高选择和自终止多也氧化硅SOI技术研究

本研究了ｎ型硅阳极化的高选择和终止工艺，并将该工艺用于形成多孔氧化硅全隔离ＳＯＩ结构。采用这种ＰＩＰＯＳ（Ｆｕｌｌ Ｉｓｏｌａｔｉｏｎ ｂｙ Ｐｏｒｏｎｓ Ｏｘｉｄｉｚｄｅ Ｓｉｉｌｃｏｎ）技术在ｎ＾－／ｎ＾＋／ｎ＾－／衬底上形成的ＳＯＩ（Ｓｉｌｉｃｏｎ Ｏｎ Ｉｎｓｕｌａｔｏｒ）结构，其顶层硅岛厚度可控制在较广范围（从１００ｎｍ到数μｍ），且硅岛宽度可大于１００μｍ．ＸＴＥＭ结果显示顶层硅／氧     

As^＋注入Si1—xGex中应变驰豫的双晶X射线衍射研究

作者首次用Ｘ射线双晶衍射技术对注入Ａｓ＾＋的Ｓｉ０．５７Ｇｅ０．４３合金的晶格损伤消除和应变驰豫进行了研究，并与未注入Ａｓ＾＋的Ｓｉ０＼５７Ｇｅ０＼４３合金的应变驰豫进行了比较。结表明，退火后，注入Ａｓ＾＋的 Ｓｉ１－ｘＧｅｘ外延层中的应变分布不同于未注入Ａｓ＾＋的应变分布。对于注入Ａｓ＾＋的Ｓｉ０．５７Ｇｅ０．４３样品，其Ｘ射线衍射峰的半宽度ＦＷＨＭ由于退火引起应变驰豫导致镶嵌结构的产生而展宽。     

多能MeV硼离子注入单晶硅形成特殊形状载流子分布

以在Ｎ型单晶硅表面１．３μｍ内实现理想平台状Ｐ型载流于分布为例，我们实验研究了多能离子注入形成特殊形状载流子分布的Ｐｅａｒｓｏｎ函数拟合叠加的计算机设计方法．首先，用扩展电阻法（ＳＲＰ）测量高温快速热退火（ＲＴＡ）后的载流子分布，对０．５—２．４ＭｅＶ能量范围内单能硼离子注入单晶硅的研究表明，Ｐｅａｒｓｏｎ函数分布比半高斯函数分布更好地符合实验所测的载流子分布．给出了投影射程凡、射程歧离σ、偏斜度γ和峭度β对能量的依赖关系．还由双能离于注入研究了注入顺序对分布的峰位和峰高的影响及两个单能分布线性叠加的条件     

小鼠精子发生过程中的Ca^2＋及Ca^2＋ATPase定位

利用电镜细胞化学方法，定位观察精子发生过程中的Ｃａ＾２＋及Ｃａ＾２＋－ＡＴＰａｓｅ变化，发现精原细胞的核内外均有弥散性的Ｃａ＾２＋分布，精母细胞，圆型精子细胞Ｃａ＾２＋主要分布在核膜，线粒体，胞质小囊，内质网，及细胞质膜上；变态期精子Ｃａ＾２＋则分布于精子顶体内膜与核膜之间。Ｃａ＾２＋－ＡＴＰａｓｅ在精子发生过程中则出现两次，一次是在精母细胞期，另一次是在变态期精子。     

GaAs低能Si^＋及SiF^＋离子注入研究

本文对３０ｋｅｖ Ｓｉ＾＋和分子离子ＳｉＦ＾＋注入半绝缘ＧａＡｓ的行为进行了研究对比。注入Ｓｉ＾２＋样品的Ｓｉ原子纵向分布与相同条件下用ＳＩＣＴ模拟程序理论计算出的分布相一致。经灯光９００℃１０″ＲＴＡ，电激活率可达６０％，电化学Ｃ－Ｖ测得的载流子纵向分布与注入态ＳＩＭＳ结果相同，可以获得近０．２μｍ的ＧａＡｓ有源层。而注入分子离子ＳｉＦ＾＋样品，虽注入层较浅，但灯光退火后，电激活率很低。因此，用     

F2^＋型色心激光器中辅助光的作用

Ｆ２＾＋型心具有跃迁偶极矩大、Ｓｔｏｋｅｓ位移适当、效率高、调谐范围覆盖０．８￣４．０μｍ近外区等优点。是一种具有实际应用价值的色心激光工作心。它的能级结构可用Ｈ２＾＋模型加以描述。利用与激光运转相关的１ｓσｇ、２ｐσｕ、２ｐπｕ能级的正常态和弛豫态特征可以阐述Ｆ２＾＋型心的激光四能级系统和辅助光的作用。多数Ｆ２＾＋型色心激光器的稳定运转需要有辅助光的激励。辅助光产生的重取向可以抵消泵光产生的重取     

SIMOX材料注F+后的SIMS分析

实验中采用三种剂量注入ＳＩＭＯＸ材料中,注入剂量分别为５×１０＾１２Ｆ＾＋／ｃｍ＊＾２,５×１０＾１３Ｆ＾＋／ｃｍ＾２,１×１０＾５Ｆ＾＋／ｃｍ＾２,用ＳＩＭＳ技术了Ｆ在材料中的浓度分析,结果表明,随着注Ｆ＾＋能量和剂量的改变,Ｆ＾＋在材料中的深度分布也相应改变。     

用C^＋＋开发黑板模型专家系统

Ｃ＾＋＋语言是一种面向对象的程序设计语言，而面向对象技术（ＯＯ）是当前计算机界讨论的热点；另一方面，知识信息处理也正在成为计算机应用的主要领域，简明地讨论了面向对象技术与专家系统中的黑板模型相结合的思想，以及采用Ｃ＾＋＋语言在专家系统中应用的可行性和优越性，并用Ｃ＾＋＋语言开发了一个黑板模型专家系统。     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.     

GaAsSb/InAlAs PA DHBTs Grown by Production MBE

The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO＞6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.     

Propagation of hermite-cosh-gaussian beams passing through ABCD optical system with an annular aperture

By using the expansion of the aperture function into a finte sum of complex Gaussian functions, the corresponding analytical expressions of Hermite-cosh-Gaussian beams passing through annular apertured paraxially and symmetrically optical systems written in terms of ABCD matrix were derived, and they could reduce to the cases with squared aperture. In a similar way, the corresponding analytical expressions of cosh-Gaussian beams through annular apertured ABCD matrix were also given. The method could save more calculation time than that by using the diffraction integral formula directly.     

Noise character analysis and the restraint of self-pulsation laser diodes

We calculate the Langevin noise sources of self-pulsation laser diodes, analyze the effects of active region noise and saturable-absorption region noise on the power fluctuation as well as period fluctuation, and propose a novel method to restrain the noise effects. A visible SIMULINK model is established to simulate the system, The results indicate that the effects of noise in absorption region can be ignored; that with the increase of DC injecting current, the noise effects enhance power jitter, and nevertheless, the period jitter is decreased; and that with external sinusoidal current modulating the self-pulsation laser diode, the noise-induced power jitter and period jitter can be suppressed greatly. This work is valuable for clock recovery in all-optical network.     

Influence of polarization extinction ratio on distributed polarization coupling detection

Distributed polarization coupling in polarization-maintaining fibers can be detected by using a white light Michelson interferometer. This technique usually requires that only one polarization mode is excited. However, in practical measurement, the injection polarization direction could not be exactly aligned to one of the principal axes of the PMF, so the influence of the polarization extinction ratio should be considered. Based on the polarization coupling theory, the influence of the incident polarization extinction on the measurement result is evaluated and analyzed, and a method for distributed polarization coupling detection is developed when both two orthogonal eigenmodes are excited.     

High-quality single-crystal CdSe nanoribbons and their optical properties

Large-scale synthesis of single-crystal CdSe nanoribbons is achieved by a modified thermal evaporation method, in which two-step-thermal-evaporation is used to control CdSe sources＇ evaporation. The synthesized CdSe nanoribbons are usually several micrometers in width, 50 nm in thickness, and tens to several hundred micrometers in length. Studies have shown that high-quality CdSe nanoribbons with regular shapes can be obtained by this method. Room-temperature photolumines-cence indicates that the lasing emission at 710 nm has been observed under optical pumping （266 nm） at power densities of 25-153 kW/cm^2. The full width half maximum （FWHM） of the lasing mode is 0.67 nm     

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正Communications—VLSI Researches and industries of telecommunications have been growing rapidly in the last 20 years and will keep their high growing pace in the next decade.The involved researches and developments cover mobile communications,highway and last-mile broadband communication,domain specific communications,and emerging D2D M2M communications.Radio communication steps into its