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Dry etching of new phase-change material Al_(1.3)Sb_3Te in CF_4/Ar plasma

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Journal of Semiconductors 2012年第10期33卷 10-15页

作者：张徐饶峰刘波彭程周夕淋姚栋宁郭晓慧宋三年王良咏成岩吴良才宋志棠封松林 State Key Laboratory of Functional Materials for Informatics Laboratory of NanotechnologyShanghai Institute of Micro-System and Information TechnologyChinese Academy of Sciences graduate university of the chinese academy of sciences

The dry etching characteristic of AlSbTe film was investigated by using a CF/Ar gas *** experimental control parameters were gas flow rate into the chamber,CF/Ar ratio,the Oaddition,the chamber background pressure,and the incident RF power applied to the lower *** total flow rate was 50 sccm and the behavior of etch rate of AlSbTe thin films was investigated as a function of the CF/Ar ratio,the Oaddition,the chamber background pressure,and the incident RF *** the parameters were *** fast etch rate was up to 70.8 nm/min and a smooth surface was achieved using optimized etching parameters of CFconcentration of 4%,power of 300 W and pressure of 80 mTorr.

关键词： Al1.3Sb3Te dry etching CF4/Ar gas mixture etch rate

Impacts of Diurnal Variation of Mountain-plain Solenoid Circulations on Precipitation and Vortices East of the Tibetan Plateau during the Mei-yu Season

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Advances in Atmospheric sciences 2014年第1期31卷 139-153页

作者： ZHANG Yuanchun SUN Jianhua FU Shenming Institute of Atmospheric Physics Chinese Academy of Sciences graduate university of the chinese academy of sciences State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences

Diurnal variations of two mountain-plain solenoid （MPS） circulations associated with ＂first-step＂ terrain [Tibetan Plateau （TP）] and ＂second-step＂ terrain （high mountains between the TP and ＂east plains＂） in China and their influence on the south west vortex （SWV） and the mei-yu front vortex （MYFV） were investigated via a semi-idealized mesoscale numerical model [Weather Research and Forecasting （WRF）] simulation integrated with ten-day average fields （mei-yu period of 1-10 July 2007）. The simulations successfully reproduced two MPS circulations related to first and second-step terrain, diurnal vari- ations from the eastern edge of the TP to the Yangtze River-Huaihe River valleys （YHRV）, and two precipitation maximum centers related to the SWV, MYFV. Analyses of the averaged final seven-day simulation showed the different diurnal peaks of precipitation at different regions： from the aftemoon to early evening at the eastern edge of the TP; in the early evening to the next early morning in the Sichuan Basin （SCB）; and in the late evening to the next early morning over the mei-yu front （MYF）. Analyses of individual two-day cases confirmed that the upward branches of the nightlime MPS circulations enhanced the precipitation over the SWV and the MYFV and revealed that the eastward extension of the SWV and its con vection were conducive to triggering the MYFVs. The eastward propagation of a rainfall streak from the eastern edge of the TP to the eastern coastal region was primarily due to a series of convective activities of several systems from west to east, including the MPS between the TP and SCB, the SWV, the MPS between second-step terrain and tile east plains, and the MYFV.

关键词： mountain-plain solenoid (MPS) diurnal variation mei-yu front

The Structure of Background-error Covariance in a Four-dimensional Variational Data Assimilation System:Single-point Experiment

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Advances in Atmospheric sciences 2010年第6期27卷 1303-1310页

作者：刘娟娟王斌王曙东 State Key Laboratory of Numerical Modeling for Atmospheric sciences &Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences graduate university of the chinese academy of sciences

A four dimensional variational data assimilation （4DVar） based on a dimension-reduced projection （DRP-4DVar） has been developed as a hybrid of the 4DVar and Ensemble Kalman filter （EnKF） concepts. Its good flow-dependent features are demonstrated in single-point experiments through comparisons with adjointbased 4DVar and three-dimensional variational data （3DVar） assimilations using the fifth-generation Pennsylvania State university-National Center for Atmospheric Research Mesoscale Model （MM5）. The results reveal that DRP-4DVar can reasonably generate a background error covariance matrix （simply B-matrix） during the assimilation window from an initial estimation using a number of initial condition dependent historical forecast samples. In contrast, flow-dependence in the B-matrix of MM5 4DVar is barely detectable. It is argued that use of diagonal estimation in the B-matrix of the MM5 4DVar method at the initial time leads to this failure. The experiments also show that the increments produced by DRP-4DVar are anisotropic and no longer symmetric with respect to observation location due to the effects of the weather trends captured in its B-matrix. This differs from the MM5 3DVar which does not consider the influence of heterogeneous forcing on the correlation structure of the B-matrix, a condition that is realistic for many situations. Thus, the MM5 3DVar assimilation could only present an isotropic and homogeneous structure in its increments.

关键词： DRP-4DVar data assimilation flow dependence single-point experiment

The Response of First Flowering Dates to Abrupt Climate Change in Beijing

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Advances in Atmospheric sciences 2011年第3期28卷 564-572页

作者：白洁葛全胜戴君虎 Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Institute of Earth Environment Chinese Academy of Sciences graduate university of the chinese academy of sciences

Phenological data on the First Flowering Date(FFD) of woody plants in Beijing from 1963-2007 are *** correlation between each species’ yearly FFD and the mean monthly temperatures for every year over a 45-year period is used to identify the month in which temperature has the most effect on FFD. Through further analysis,the FFDs of 48 woody plant species are shown to have advanced an average of 5.4 days from 1990-2007 compared to *** results indicate that 70.8%of species flowered significantly earlier(7 days on average) during the period 1990-2007,while only one species(2.1%) flowered significantly ***,the responses of FFD to climate change are shown to be different in two climatic stages, defined by an abrupt climate change ***-three species which first flower in March and April are sensitive to temperature are *** correlation coefficients between FFD and temperature for 20 species during the latter period(1990-2007) are shown to be larger than during the former period(1963- 1989),with a difference of around -0.87 days per 1℃on *** paper concludes that with the warming of climate,the linear trend of FFD variation,as well as its responsiveness to temperature,became more prominent during 1990-2007 than *** data analyzed in this study present a strong biological indicator of climate change in Beijing,and provide further confirmation of previous results from regional and local studies across the Northern *** variations indicate that the climate is changing rapidly.

关键词： phenology climate change first flowering date(FFD) woody plants

Atmospheric Angular Momentum Transport and Balance in the AGCM-SAMIL

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Advances in Atmospheric sciences 2010年第5期27卷 1183-1192页

作者：李军吴国雄 State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences graduate university of the chinese academy of sciences National Meteorological Center

NCEP/NCAR reanalysis data and the spectral atmospheric general circulation Model （AGCM） of IAP/LASG （SAMIL） are employed to investigate the transport and balance of atmospheric angular mo-mentum （AAM）. It is demonstrated that SAMIL depicts the general features of the AAM transport and balance reasonably well. The AAM sources are in the tropics and sinks are in the mid-latitudes. The strongest meridional transport occurs in the upper troposphere. The atmosphere gains westerly momen- tum and transports it upward in the areas of surface easterlies, and downward into the areas of surface westerlies. Consequently, AAM balance is maintained. Systematic biases of the model compared to the reanalysis and observations are revealed. Possible mechanisms for these biases are investigated. In SAMIL, the friction torque in the tropics is stronger compared to the observations, which is probably due to the excessive precipitation along the Inter-tropical convergence zone （ITCZ） in the model, since the simulated Hadley circulation is much stronger than observed. In the winter half of the year, the transport center is in the lower troposphere in the SAMIL model, but it is in the upper troposphere in the reanalysis and observations. These discrepancies also suggest that simulations of convection and tropical precipitation need to be improved and that higher resolution is necessary for a quantitative simulation of AAM transport and balance. Results also demonstrate that the analysis of the transport and balance of atmospheric angular momentum is a powerful tool in diagnosing climate models for potential improvement.

关键词： angular momentum friction torque mountain torque

Broader pattern of tandem repeats in the mitochondrial control region of Perciformes

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chinese Journal of Oceanology and Limnology 2010年第4期28卷 785-794页

作者：崔朝霞刘媛朱嘉濠 EMBL Institute of OceanologyChinese Academy of Sciences graduate university of the chinese academy of sciences Department of Biology Chinese University of Hong Kong

Perciformes,the largest order of vertebrates with 20 suborders,is the most diverse fish order that dominates vertebrate ocean *** complete mitochondrial control region(CR) of Trichiurus japonicus(Trichiuridae,Scombroidei) and Pampus sp.(Stromateidae,Stromateoidei) were amplified and *** with data from GenBank,the tandem repeats in the mitochondrial CR from 48 species,which covered nine suborders of Perciformes,are reported in this *** tandem repeats tend to be long in the suborder Percoidei and *** identical repeats in 21 species of Cichlidae suggest a common origin and have existed before species *** crocea shows tandem repeats instead of the typical structure of the central conserved sequence blocks,which was first reported in Perciformes and *** might have resulted from interruption of the polymerase activity during the H-strand *** four broader patterns presented here for the tandem repeats,including those in both the 5' and 3' ends,only in the either 5' or 3' end,and in the central conserved domain of the control region,will be useful for understanding the evolution of species.

关键词： mtDNA control region tandem repeats Perciformes evolution

Algorithm Studies on How to Obtain a Conditional Nonlinear Optimal Perturbation (CNOP)

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Advances in Atmospheric sciences 2010年第6期27卷 1311-1321页

作者：孙国栋穆穆张雅乐 The State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences Key Laboratory of Ocean Circulation and Wave Institute of OceanologyChinese Academy of Sciences graduate university of the chinese academy of sciences

The conditional nonlinear optimal perturbation （CNOP）, which is a nonlinear generalization of the linear singular vector （LSV）, is applied in important problems of atmospheric and oceanic sciences, including ENSO predictability, targeted observations, and ensemble forecast. In this study, we investigate the computational cost of obtaining the CNOP by several methods. Differences and similarities, in terms of the computational error and cost in obtaining the CNOP, are compared among the sequential quadratic programming （SQP） algorithm, the limited memory Broyden-Fletcher-Goldfarb-Shanno （L-BFGS） algorithm, and the spectral projected gradients （SPG2） algorithm. A theoretical grassland ecosystem model and the classical Lorenz model are used as examples. Numerical results demonstrate that the computational error is acceptable with all three algorithms. The computational cost to obtain the CNOP is reduced by using the SQP algorithm. The experimental results also reveal that the L-BFGS algorithm is the most effective algorithm among the three optimization algorithms for obtaining the CNOP. The numerical results suggest a new approach and algorithm for obtaining the CNOP for a large-scale optimization problem.

关键词： conditional nonlinear optimal perturbation constrained optimization problem unconstrainedoptimization problem

Diagnostic Analysis of the Evolution Mechanism for a Vortex over the Tibetan Plateau in June 2008

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Advances in Atmospheric sciences 2011年第4期28卷 797-808页

作者：李论张人禾温敏 State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences graduate university of the chinese academy of sciences State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences

Based on the final analyses data （FNL） of the Global Forecasting System of the NCEP and the obser- vational radiosonde data, the evolution mechanism of an eastward-moving low-level vortex over the Tibetan Plateau in June 2008 was analyzed. The results show that the formation of the vortex was related to the convergence between the northwesterly over the central Tibetan Plateau from the westerly zone and the southerly from the Bay of Bengal at 500 hPa, and also to the divergence associated with the entrance re- gion of the upper westerly jet at 200 hPa. Their dynamic effects were favorable for ascending motion and forming the vortex over the Tibetan Plateau. Furthermore, the effect of the atmospheric heat source （Q1） is discussed based on a transformed potential vorticity （PV） tendency equation. By calculating the PV budgets, we showed that Q1 had a great inffuence on the intensity and moving direction of the vortex. In the developing stage of the vortex, the heating of the vertically integrated Q1 was centered to the east of the vortex center at 500 hPa, increasing PV tendency to the east of the vortex. As a result, the vortex strengthened and moved eastward through the vertically uneven distribution of Q1. In the decaying stage, the horizontally uneven heating of Q1 at 500 hPa weakened the vortex through causing the vortex tubes around the vortex to slant and redistributing the vertical vorticity field.

关键词： Tibetan Plateau low-level vortex atmospheric heat source PV tendency equation

Total ionizing dose effect in an input/output device for flash memory

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chinese Physics B 2011年第12期20卷 187-191页

作者：刘张李胡志远张正选邵华陈明毕大炜宁冰旭邹世昌 The State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences graduate university of the chinese academy of sciences

Input/output devices for flash memory are exposed to gamma ray irradiation. Total ionizing dose has been shown great influence on characteristic degradation of transistors with different sizes. In this paper, we observed a larger increase of off-state leakage in the short channel device than in long one. However, a larger threshold voltage shift is observed for the narrow width device than for the wide one, which is well known as the radiation induced narrow channel effect. The radiation induced charge in the shallow trench isolation oxide influences the electric field of the narrow channel device. Also, the drain bias dependence of the off-state leakage after irradiation is observed, which is called the radiation enhanced drain induced barrier lowing effect. Finally, we found that substrate bias voltage can suppress the off-state leakage, while leading to more obvious hump effect.

关键词： input/output device oxide trapped charge radiation induced narrow channel effect,shallow trench isolation total ionizing dose