基于GaAs工艺的36GHz压控振荡器

利用法国OMMIC公司的0.2μm GaAs PHEMT工艺,设计实现了一个36GHz压控振荡器电路.该电路采用完全差分的调谐振荡器结构,通过引进容性源极耦合差动电流放大器和调谐负载电路,提高了电路的性能.测试表明:该压控振荡器中心频率为36GHz,调谐范围约为800MHz,在偏离中心频率10MHz处的单边带相位噪声为-98.83dBc/Hz.芯片面积为0.5mm×1mm,采用-5V单电源供电,核心单元功耗约为200mW.     

精确的1.08GHz CMOS电感电容压控振荡器

在0.35μm 2P4M标准CMOS工艺上,设计了一个精确的1.08GHz CMOS电感电容压控振荡器.提出了一种有效计算压控振荡器周期的新方法,采用该方法计算的频率-电压调谐曲线与实验结果吻合得很好.在电源电压3.3V下,消耗电流3.1mA,压控振荡器的相位噪声在10kHz频偏处为-82.2dBc/Hz.芯片面积为0.86mm×0.82mm.     

基于GaAs工艺的36GHz压控振荡器

利用法国OMMIC公司的0.2μm GaAs PHEMT工艺,设计实现了一个36GHz压控振荡器电路.该电路采用完全差分的调谐振荡器结构,通过引进容性源极耦合差动电流放大器和调谐负载电路,提高了电路的性能.测试表明:该压控振荡器中心频率为36GHz,调谐范围约为800MHz,在偏离中心频率10MHz处的单边带相位噪声为-98.83dBc/Hz.芯片面积为0.5mm×1mm,采用-5V单电源供电,核心单元功耗约为200mW.     

一种0.13微米CMOS工艺1.0V差分压控振荡器设计

本文实现了一种集成高品质因素片上电感的差分互补压控振荡器。该压控振荡器的谐振腔由片上电感和反型MOS电容并联组成。谐振腔的品质因素主要被片上电感性能所限制。通过优化设计以及采用单圈的拓扑结构,片上电感在6GHz仿真的品质因素可以达到35。本文提出的压控振荡器采用SMIC0.13微米工艺流片,芯片面积为1.0×0.8mm2。振荡器的频率范围为5.73GHz到6.35GHz。当振荡器中心频率为6.35GHz时,其功耗在1.0V电源电压时为2.55mA,1MHz频偏处相位噪声为-120.14dBc/Hz。该压控振荡器的FOM值达到-192.13dBc/Hz.     

一种基于多协议电流复用双频段压控振荡器的设计

.本文设计了一种基于IEEE 802.11 a/b/g和蓝牙多协议零中频收发机中双频段压控振荡器.该振荡器使用电流复用的方法,即将两个工作在不同频段的压控振荡器串联堆叠,达到了降低功耗的目的.通过Aglient ADS仿真,结果表明本文所设计的双频段压控振荡器功耗为12.22 mW,2.44和5.23 GHz载频处的相位噪声分别为-126.2和-120.1dBc/Hz@1 MHz,其性能完全符合IEEE 802.11a/b/g和蓝牙协议的要求.该振荡器将采用0.18 μm CMOS工艺实现,芯片面积为1.18 mm×0.67 mm.     

IOGHz 0.25μm CMOS LC压控振荡器

采用标准0.25μm CMOS工艺实现了10GHz LC压控振荡器.为了适应高频工作,并实现低相位噪声,该压控振荡器采用了手动优化的带中心抽头的对称电感,将A-MOS变容二极管与无源金属-绝缘层-金属电容串联,并采用了带LC滤波器的尾电流源.测试结果显示,当振荡频率为10.2GHz时,在1MHz频偏处相位噪声为-103.2dBc/Hz,调谐范围为11.5%.供电电压为3.3V时,核心电路功耗为9.0mW.芯片面积为0.67mm×0.58mm.     

IOGHz 0.25μm CMOS LC压控振荡器

采用标准0.25μm CMOS工艺实现了10GHz LC压控振荡器.为了适应高频工作,并实现低相位噪声,该压控振荡器采用了手动优化的带中心抽头的对称电感,将A-MOS变容二极管与无源金属-绝缘层-金属电容串联,并采用了带LC滤波器的尾电流源.测试结果显示,当振荡频率为10.2GHz时,在1MHz频偏处相位噪声为-103.2dBc/Hz,调谐范围为11.5%.供电电压为3.3V时,核心电路功耗为9.0mW.芯片面积为0.67mm×0.58mm.     

宽频率范围的单子带压控振荡器设计

基于TSMC 180 nm CMOS工艺,提出了一种振荡频率为2~3 GHz的宽频率范围、低相位噪声的单子带压控振荡器(VCO)。采用双平衡吉尔伯特混频结构,将单子带5~6 GHz压控振荡器与固定频率3 GHz压控振荡器进行下混频,可得到振荡频率为2~3 GHz的单子带压控振荡器,实现相对带宽从18.18%到40%的展宽。其中5~6 GHz单子带压控振荡器采用互补交叉耦合结构,更易达到起振条件,采用两组可变电容的并联形式以提高调谐曲线的线性度,拓宽压控振荡器的输出频率调谐范围。通过芯片测试验证,在1.8 V电源电压下,调谐电压变化范围为0.6~2.8 V时,实际输出频率范围为1.85~3 GHz,最大调谐灵敏度为1000 MHz/V,2 GHz频点处相位噪声为-123.2 dBc/Hz@1 MHz,芯片尺寸为1.2 mm×0.7 mm。     

集成低功耗CMOS压控振荡器及其二分频器

实现了应用于无线局域网收发机的集成低功耗CMOS压控振荡器及其二分频器.压控振荡器是由在片对称螺旋型电感和差分容抗管组成的LC负阻型振荡器,而二分频器采用了ILFD结构.由于采用了差分LC元件和ILFD技术,整个电路的功耗很低.该电路已经用0.18μm CMOS工艺实现.测试结果表明该电路能产生低相位噪声的3.6/1.8GHz双带本振信号,并具有很宽的可控频率范围.当电源电压为1.5V时,该电路消耗了5mA的电流.芯片面积为1.0mm×1.0mm.     

集成低功耗CMOS压控振荡器及其二分频器

实现了应用于无线局域网收发机的集成低功耗CMOS压控振荡器及其二分频器.压控振荡器是由在片对称螺旋型电感和差分容抗管组成的LC负阻型振荡器,而二分频器采用了ILFD结构.由于采用了差分LC元件和ILFD技术,整个电路的功耗很低.该电路已经用0.18μm CMOS工艺实现.测试结果表明该电路能产生低相位噪声的3.6/1.8GHz双带本振信号,并具有很宽的可控频率范围.当电源电压为1.5V时,该电路消耗了5mA的电流.芯片面积为1.0mm×1.0mm.     

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.     

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.     

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     

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.     

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.     

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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