深亚微米PD和FD SOI MOS器件热载流子损伤的研究

研究了深亚微米PD和FD SOI MOS器件遭受热截流子效应(HCE)后引起的器件参数退化的主要差异及其特点，提出了相应的物理机制，以解释这种特性。测量了在不同应力条件下最大线性区跨导退化和闽值电压漂移，研究了应力Vg对HCE退化的影响，并分别预测了这两种器件的寿命，提出了10年寿命的0．3μm沟长的PD和FD SOI MOS器件所能承受的最大漏偏压。     

不同HALO掺杂剂量的超薄栅pMOSFET的退化

研究了热载流子应力下栅厚为2.1nm,栅长为0.135μm的pMOSFET中HALO掺杂剂量与器件的退化机制和参数退化的关系.实验发现,器件的退化机制对HALO掺杂剂量的改变不敏感,但是器件的线性漏电流、饱和漏电流、最大跨导的退化随着HALO掺杂剂量的增加而增加.实验同时发现,器件参数的退化不仅与载流子迁移率的退化、漏串联电阻增大有关,而且与阈值电压的退化和应力前阈值电压有关.     

pMOS器件的热载流子注入和负偏压温度耦合效应

研究了在热载流子注入HCI(hotcarrier injection)和负偏温NBT(negative bias temperature)两种偏置条件下pMOS器件的可靠性．测量了pMOS器件应力前后的电流电压特性和典型的器件参数漂移，并与单独HCI和NBT应力下的特性进行了对比．在这两种应力偏置条件下，pMOS器件退化特性的测量结果显示高温NBT应力使得热载流子退化效应增强．由于栅氧化层中的固定正电荷引起正反馈的热载流子退化增强了漏端电场，使得器件特性严重退化．给出了NBT效应不断增强的HCI耦合效应的详细解释．     

不同HALO掺杂剂量的超薄栅pMOSFET的退化

研究了热载流子应力下栅厚为2 .1nm ,栅长为0 .135μm的p MOSFET中HAL O掺杂剂量与器件的退化机制和参数退化的关系.实验发现,器件的退化机制对HAL O掺杂剂量的改变不敏感,但是器件的线性漏电流、饱和漏电流、最大跨导的退化随着HAL O掺杂剂量的增加而增加.实验同时发现,器件参数的退化不仅与载流子迁移率的退化、漏串联电阻增大有关,而且与阈值电压的退化和应力前阈值电压有关.     

pMOS器件的热载流子注入和负偏压温度耦合效应

研究了在热载流子注入HCI(hot-carrier injection)和负偏温NBT(negative bias temperature)两种偏置条件下pMOS器件的可靠性.测量了pMOS器件应力前后的电流电压特性和典型的器件参数漂移,并与单独HCI和NBT应力下的特性进行了对比.在这两种应力偏置条件下,pMOS器件退化特性的测量结果显示高温NBT应力使得热载流子退化效应增强.由于栅氧化层中的固定正电荷引起正反馈的热载流子退化增强了漏端电场,使得器件特性严重退化.给出了NBT效应不断增强的HCI耦合效应的详细解释.     

超深亚微米LDD nMOSFET中的非幸运电子模型效应

通过对采用0.18μm CMOS工艺制造的两组不同沟道长度和栅氧厚度的LDD器件电应力退化实验发现，短沟薄栅氧LDD nMOSFET（Lg=0.18μm，Tox=3.2nm）在沟道热载流子(CHC)应力下的器件寿命比在漏雪崩热载流子（DAHC）应力下的器件寿命要短，这与通常认为的DAHC应力（最大衬底电流应力）下器件退化最严重的理论不一致．因此，这种热载流子应力导致的器件退化机理不能用幸运电子模型（LEM）的框架理论来解释．认为这种“非幸运电子模型效应”是由于最大碰撞电离区附近具有高能量的沟道热电子，在Si-SiO2界面产生界面陷阱(界面态)的区域，由Si-SiO2界面的栅和漏的重叠区移至沟道与LDD区的交界处以及更趋于沟道界面的运动引起的．     

脉冲应力增强的NMOSFET's热载流子效应研究

 本文研究了交流应力下的热载流子效应,主要讨论了脉冲应力条件下的热空穴热电子交替注入对NMOSFET's的退化产生的影响.在脉冲应力下,阈值电压和跨导的退化增强.NMOSFET's在热空穴注入后,热电子随后注入时,会有大的退化量,这可以用中性电子陷阱模型和脉冲应力条件下热载流子注入引起的栅氧化层退化来解释.本文还定量分析研究了NMOSFET's退化与脉冲延迟时间和脉冲频率的关系,并且给出了详细的解释.在脉冲应力条件下,器件的热载流子退化是由低栅压下注入的热空穴和高栅压下热电子共同作用的结果.     

脉冲应力增强的NMOSFET′s热载流子效应研究

本文研究了交流应力下的热载流子效应 ,主要讨论了脉冲应力条件下的热空穴热电子交替注入对NMOSFET′s的退化产生的影响 .在脉冲应力下 ,阈值电压和跨导的退化增强 .NMOSFET′s在热空穴注入后 ,热电子随后注入时 ,会有大的退化量 ,这可以用中性电子陷阱模型和脉冲应力条件下热载流子注入引起的栅氧化层退化来解释 .本文还定量分析研究了NMOSFET′s退化与脉冲延迟时间和脉冲频率的关系 ,并且给出了详细的解释 .在脉冲应力条件下 ,器件的热载流子退化是由低栅压下注入的热空穴和高栅压下热电子共同作用的结果     

深亚微米抗辐照PDSOI nMOSFET的热载流子效应

基于中国科学院微电子研究所开发的0.35 μm SOI工艺,制备了深亚微米抗辐照PDSOI H型栅nMOSFET.选取不同沟道宽度进行加速应力实验.实验结果表明,热载流子效应使最大跨导变化最大,饱和电流变化最小,阈值电压变化居中.以饱和电流退化10%为失效判据,采用衬底/漏极电流比率模型,对器件热载流子寿命进行估计,发现同等沟道长度下,沟道越宽的器件,载流子寿命越短.     

超深亚微米LDD nMOSFET中的非幸运电子模型效应

通过对采用0.18μm CMOS工艺制造的两组不同沟道长度和栅氧厚度的LDD器件电应力退化实验发现,短沟薄栅氧LDD nMOSFET(Lg=0.18μm,Tox=3.2nm)在沟道热载流子(CHC)应力下的器件寿命比在漏雪崩热载流子(DAHC)应力下的器件寿命要短,这与通常认为的DAHC应力(最大衬底电流应力)下器件退化最严重的理论不一致.因此,这种热载流子应力导致的器件退化机理不能用幸运电子模型(LEM)的框架理论来解释.认为这种"非幸运电子模型效应"是由于最大碰撞电离区附近具有高能量的沟道热电子,在Si-SiO2界面产生界面陷阱(界面态)的区域,由Si-SiO2界面的栅和漏的重叠区移至沟道与LDD区的交界处以及更趋于沟道界面的运动引起的.     

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