超低电压正交压控振荡器设计

提出一种新的低压正交压控振荡器(QVCO)结构,该结构由两个完全相同的低压压控振荡器经过背栅耦合方式实现.背栅耦合方式使压控振荡器实现正交的输出时钟并且降低了功耗和输出相位噪声.该设计中的QVCO电路采用中芯国际0.13μm 1P8M标准CMOS工艺,可以工作在0.35V的电源电压下,总的功耗为1.75mW,输出时钟频率为5.34GHz,偏离主频1MHz处的相位噪声为-110.5dBc/Hz,对应该相位噪声的FOM(FigureOf-Merit)为-182.62dBc/Hz,频率调谐范围为4.92~5.34GHz.该QVCO可以在更低的电源电压下实现低的相位噪声,且拥有较高的FOM值.     

UHF RFID中低噪声正交压控振荡器设计

采用标准0.18μm RF CMOS工艺,设计了一种低相位噪声正交压控振荡器(QVCO)电路。该QVCO电路采用了两种新技术:分裂转换偏置与电容耦合技术。该电路不仅获得较好的相位噪声,还具有良好的相位误差。仿真结果表明,1.8V电压下,电路功耗为10.28mW。实现了848.1MHz~1.048GHz的调谐范围,输出频率为920MHz时,在频偏1MHz处,相位噪声为-127.5dBc/Hz,相位误差最小可达到0.01°。     

低功耗低噪声正交压控振荡器设计

设计了一种用于WLAN 802.11 n收发机频率合成器的新颖低功耗、低相位噪声正交输出LC电压控制振荡器(QVCO)。电路设计中使用了Cadence IC5.033和ADS2004软件以及TSMC0.18μm CMOS工艺模型库,电路依靠并联的耦合支路相互作用使两个独立压控振荡器输出相位成正交,采用PMOS并联耦合支路和开关控制偏置两种新技术降低了VCO的相位噪声,其仿真结果为1 MHz频偏处-128.6 dBc/Hz和10 kHz频偏处-84 dBc/Hz。采用数字电容阵列提高了QVCO的频率调谐范围,QVCO的频率范围仿真结果为3.1 GHz~4.1 GHz。QVCO的电源电压为1.8 V,功耗17 mW。实现了低功耗正交输出压控振荡器,同时通过新颖的电路设计技术改善了相位噪声,改变了正交输出LC压控振荡器高噪声的传统观念,为今后在正交输出LC压控振荡器的设计提供了一些参考。     

基于超谐波注入锁定的低相噪QVCO的设计

对基于注入锁定的正交压控振荡器(QVCO)电路进行了研究和分析,设计了一个低相位噪声、低相位误差的QVCO电路,该电路由两个电感电容压控振荡器(LC VCO)在正交相位进行超谐波耦合,通过一个频率倍增器在交叉耦合对的共模信号点注入同步信号.通过对相位误差公式的推导,提出了降低相位误差的方法,由于该电路在共模点采用二倍频取样,抑制了尾电流的闪烁噪声,降低了相位噪声.电路基于TSMC 0.18 μm互补金属氧化物半导体(CMOS)工艺实现,测试结果表明,当谐振频率从4.5 GHz调谐到4.9 GHz时,在电源电压为1.8V时,电路消耗功率为13 mW,1 MHz频偏处的单边带(SSB)相位噪声为-129.95 dBc/Hz,与传统的QVCO相比,噪声性能得到了改善.     

基于HBT工艺的高功率低相位噪声QVCO

基于Sanan 2 μm GaAs HBT工艺,提出了一种差分Colpitts结构的高功率低相位噪声正交压控振荡器(QVCO)。该QVCO采用四只环形连接的二极管,通过二次谐波反相作用,迫使压控振荡器基波正交。该QVCO比传统串并联晶体管耦合电路具有更高的输出功率和更低的相位噪声。仿真结果表明,该QVCO的调谐范围为12.98~14.05 GHz。振荡频率为13.51 GHz时,输出信号功率为12.557 dBm。相位噪声为-117.795 dBc/Hz @1 MHz。     

2.4 GHz低相位误差低相位噪声CMOS QVCO设计

提出了一种新型的适用于锁相环频率合成器的正交压控振荡器(QVCO)结构,分析了QVCO的工作原理及其相位噪声性能.ADS仿真结果表明,电路工作在2.4 GHz、偏离中心频率600 kHz的情况下相位噪声为-115.4 dBc/Hz,在1.8 V电源下功耗仅为2.9 mW,输出信号的相位误差小于0.19°.结果还表明相对于目前流行的QVCO结构,提出的结构实现了低相位误差、低功耗、高FoM值.     

基于自注入耦合技术的超低相位噪声QVCO

基于标准0.18μm CMOS工艺,提出并验证了一种改进的用于多相位振荡器的耦合方法。将一种先进的自注入耦合(SIC)技术,用于耦合两个电流复用差分压控振荡器(VCO)。相比较于传统的并联耦合正交VCO(QVCO)而言,所提出的采用SIC技术的QVCO在没有增加功耗的前提下,表现出了更低的相位噪声。所提出的SIC-QVCO在16.41GHz振荡频率下,相位噪声为-119.7dBc/Hz@1MHz,并且调谐范围高达1.66GHz,直流电源电压和电流分别为1.8V和5.28mA,芯片尺寸为0.3mm×0.9mm。     

一种4.224GHz正交压控振荡器的设计

设计了一种应用于MB-OFDM UWB射频频率综合器的工作于4.224GHz的正交压控振荡器(QVCO),并采用0.18μm RF-CMOS工艺进行了设计实现.该Qvco通过改进结构能够得到更好的相位噪声.通过改变MOS变容管的接入方法实现了更好的压控增益线性度,并采用了新的低寄生电容、低导通电阻的数控电容阵列结构来补偿工艺变化带来的频率变化.测试结果表明,该QV-CO在4.224GHz附近的100kHz频偏处的相位噪声为-90.4dBc/Hz,1MHz频偏处的相位噪声为-116.7dBc/Hz,整个QVCO电路功耗为10.55mW,电源电压为1.8V.     

一种4.224GHz正交压控振荡器的设计

设计了一种应用于MB-OFDM UWB射频频率综合器的工作于4.224GHz的正交压控振荡器(QVCO),并采用0.18μm RF-CMOS工艺进行了设计实现.该Qvco通过改进结构能够得到更好的相位噪声.通过改变MOS变容管的接入方法实现了更好的压控增益线性度,并采用了新的低寄生电容、低导通电阻的数控电容阵列结构来补偿工艺变化带来的频率变化.测试结果表明,该QV-CO在4.224GHz附近的100kHz频偏处的相位噪声为-90.4dBc/Hz,1MHz频偏处的相位噪声为-116.7dBc/Hz,整个QVCO电路功耗为10.55mW,电源电压为1.8V.     

高性能超低功耗的4.224GHz正交LC VCO

采用Jazz0.18μm RF CMOS工艺设计并实现应用于MB-OFDM超宽带频率综合器的4.224GHz电感电容正交压控振荡器。通过解析的方法给出了电感电容正交压控振荡器的模型,并推导出简洁的公式解释了相位噪声性能与耦合因子的关系。测试结果显示,核心电路在1.5V电源电压下,消耗6mA电流,频率调谐范围为3.566~4.712GHz;在主频频偏1MHz处的相位噪声为-119.99dBc/Hz,对应的相位噪声的FoM(Figure-of-Merit)为183dB;I、Q两路信号等效的相位误差为2.13°。     

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.     

Technology innovation and process integrations for sub-100nm gate patterning

This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration.     

White organic light-emitting devices based on fac tris（2- phenylpyridine） iridium sensitized 5,6,11,12-tetraphenylnap -hthacene

We have fabricated the white organic light-emitting devices （WOLEDs） based on 4,4＇ -bis（2,2 -diphenyl vinyl）-1,1＇ - biphenyl （DPVBi） and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene （rubrene）. The device structure is ITO/2T-NATA （20 nm）/NPBX （20 nm）/CBP： x%Ir（ppy）3：0.5% rubrene （8 nm）/NPBX （5 nm）/DPVBi （30 nm）/Alq（30 nm）/LiF（0.5 nm）/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris （2-phenylpyridine） iridium [Ir（ppy）3], acts as a yellow light-emitting layer, and N,N＇ -bis- （1-naphthyl）- N,N＇ -diphenyl -1, 1＇ -biphenyl-4,4＇ -diamine （NPBX） acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir （PPY）3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V.     

Complete approach to automatic identification and subpixel center location for ellipse feature

To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction.     

小角度扩展相关性近似算法分析

本论文提出一种在多天线MIMO信道相关性建模中小角度扩展近似理论算法,并应用于分析MIMO系统性能。分析中分别对三种不同角能量分布情况下的空间相关性研发快速近似计算法,并同时提出双模(Bi-Modal)角能量分布情况下的近似运算。通过分析这些新方法的近似效率,可以得到计算简单、复杂度低、而且符合实际的MIMO相关信道矩阵,对系统级的快速高效计算法的研究和系统级的评估以及误差分析具有重要的意义。     

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.