真空退火对氧化钒薄膜的相成分和电学性能的影响

利用真空退火工艺处理p-Si(100)衬底上磁控溅射制备的氧化钒多晶薄膜.利用X射线衍射(XRD)分析、原子力显微镜(AFM)以及四探针测试方法,研究了退火时间对薄膜的相成分和电学性能的影响,并观察分析了氧化钒薄膜的表面形貌.研究结果表明,随着退火时间的变化,薄膜的相成分不断发生变化,钒氧比例不断升高,可以得到多种氧化钒的相.适当的真空退火处理可以改善薄膜的表面质量,并且能有效地降低氧化钒薄膜的室温电阻率达两个数量级.     

脉冲反应磁控溅射氧化钒薄膜的光谱椭偏研究

采用脉冲直流反应磁控溅射技术在不同的占空比条件下制备了氧化钒薄膜.利用X射线光电子能谱仪测定了薄膜的组分,用光谱椭偏仪在300～850 nm的波长范围内对薄膜的光学性质进行了研究.实验结果表明降低占空比具有促进金属钒氧化的作用,而通过采用Tauc-Lorentz谐振子色散模型结合有效介质近似模型对椭偏参数ψ和△进行拟合,得到了较为理想的拟合结果.薄膜的复折射率和透过率均由椭偏拟合结果确定,结果发现占空比的下降,导致了可见光范围内薄膜折射率和消光系数的降低以及透过率的提高.     

非晶氧化钛薄膜的电学特性研究

室温下,通过采用直流反应磁控溅射法在覆盖有氮化硅薄膜的单晶硅衬底上生长了厚度约为100nm的氧化钛薄膜。掠入射X射线衍射分析结果表明在室温下,不同氧分压下生长的氧化钛薄膜均具有非晶结构。分别采用场发射扫描电子显微镜、X射线光电子能谱对薄膜的表面和断面形貌以及薄膜的组分进行了分析和表征。对薄膜的电学特性测试发现非晶氧化钛薄膜在293～373K的温度范围内主要依靠热激发至扩展态中的电子导电。     

直流磁控溅射法制备非晶态氧化钒薄膜光学特性研究

研究了直流反应磁控溅射工艺中衬底温度对氧化钒(V2O5)薄膜性能的影响,利用X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、X射线衍射(XRD)和紫外-可见光分光光度计(UV1700)分别对薄膜进行了表征.实验结果表明,除了组分和晶态,薄膜的形貌和光学性能受衬底温度的影响很大.随着衬底温度的升高,膜表面变得粗糙,膜厚减小.光学特性测试表明,当衬底温度从160℃升高到320 ℃,光学带隙从2.39 eV下降到2.18 eV.     

一种高性能氧化钒热敏薄膜的制备和应用

报道一种制备高性能氧化钒热敏薄膜的方法和其应用。采用反应磁控溅射薄膜沉积技术，通过改变氧化钒热敏薄膜沉积时溅射功率，从而调整钒原子在溅射出来之后接触到基片表面时的沉积速率，同时通过对设备进行改造升级，即在钒溅射腔腔外增加一个控制电源来精确控制溅射电压及氧气分压等参数来精确控制反应过程中电流密度，优化了氧化钒薄膜的制备工艺，制备出方块电阻为500 kΩ/□，电阻温度系数（TCR）为?2.7% K?1的氧化钒薄膜。实验测试结果表明，利用高性能氧化钒热敏薄膜制作的非制冷红外焦平面探测器，其噪声等效温差（NETD）降低30%，噪声降低28%，显著提升了非制冷焦平面探测器的综合性能。     

射频磁控溅射氧化钒薄膜的结构与性能研究(英文)

以非制冷微测辐射热计型红外探测器应用为需求背景,采用射频磁控溅射技术在300℃低温条件下制备了氧化钒薄膜。采用X射线衍射(XRD)、原子力显微镜(AFM)、能量色散谱(EDS)及X射线光电子能谱(XPS)技术表征了薄膜的结晶状态、微观结构与化学组成。采用四探针技术研究了薄膜的电学性能。结果表明该薄膜主要为非晶态的二氧化钒(VO2),并具有光滑的表面形貌。这种非晶VO2薄膜在22～100℃温度范围内不存在半导体-金属相变。100 nm厚的非晶VO2薄膜室温下的面电阻为600 kΩ/□,同时表现出-2.1%/℃的较高电阻温度系数(TCR),这表明该薄膜有希望用于非制冷微测辐射热计型红外探测器。     

利用同步测量研究二氧化钒薄膜的电学与光学相变特性

利用射频磁控溅射方法在蓝宝石衬底上制备了氧化钒薄膜,X射线衍射的测量结果表明薄膜的主要成分是多晶二氧化钒.实现了二氧化钒薄膜半导体-金属相变过程的电阻和五个不同波长下薄膜反射率的同步测量.实验结果表明,电学和光学测量都在相变过程中出现回滞曲线,但是二者的表现形式有明显差别.当用光学方法探测时,同一次相变过程中不同区域的反射率曲线几乎完全重合,证明了薄膜样品的均匀性.     

磁控溅射功率对光学氧化钒薄膜结构和性能的影响

采用射频磁控溅射法制备氧化钒(VOx)薄膜,研究溅射功率对氧化钒薄膜结构、光学及力学性能的影响。利用表面轮廓仪、X射线衍射仪、原子力显微镜、分光光度计、椭偏仪及纳米压痕仪分析在不同溅射功率下制备的氧化钒薄膜的沉积速率、物相结构、表面形貌、紫外-近红外光透射率、折射率、吸光度以及硬度和弹性模量。结果表明,各功率参数下沉积的氧化钒薄膜的光透射率基本都大于80%,属于弱吸收透明膜。随溅射功率的增大,薄膜的沉积速率、硬度和可见光范围内的折射率都单调增大,而表面粗糙度则出现先增大后减小的变化。溅射功率对薄膜的晶体结构也有一定的影响。     

热处理时间对氧化钒薄膜相变性能的影响

采用直流磁控溅射的方法在普通玻璃上制备了低价的氧化钒薄膜,在氧气和氩气混合气氛中,对所制备的薄膜进行不同时间的热处理,得到具有相变特性的VO2薄膜。分别利用X射线衍射(XRD)和场发射扫描电镜(SEM)分析了薄膜的组分、结晶结构和表面形貌,利用四探针法测试了薄膜的电阻。结果表明:热处理前的氧化钒薄膜主要成分为V2O3,经过热氧化处理后,低价的氧化钒被氧化,薄膜中VO2含量增加,薄膜发生金属-半导体相变,其中450℃、2h为最佳处理参数,其电阻相变幅度超过2个数量级,薄膜的相变温度仅为30℃。     

基于常温磁控溅射法的二氧化钒薄膜制备方法研究

采用常温磁控溅射法制备金属钒薄膜,然后在合适的氧气氛围下对其进行退火氧化处理,最终在非晶玻璃衬底上制备出具有相变的高性能二氧化钒(Vanadium Dioxide,VO_2)薄膜。X射线衍射(X-Ray Diffraction,XRD)测试结果表明,所制薄膜的主要成分为VO_2;扫描电子显微镜(Scanning Electron Microscope,SEM)测试结果表明,所制薄膜的结晶性良好,晶粒粗细均匀。该薄膜在室温下的红外光透过率(2400nm处)为67%,在高温下的红外光透过率(2400 nm处)为9%。其透过率差值为58%,因此具有良好的红外透过率调节能力。同时还测试分析了薄膜光学转变与电学转变的差异,发现电学转变温度比光学转变温度高4.7℃。该方法适合大面积VO_2薄膜的制备,对智能窗的研究与应用具有重要意义。     

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。     

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.     

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.     

A Versatile Mixed-Signal Pin Approach for Cost-Effective Test of Automotive ICs

Integrated circuits (ICs) intended for increasingly sophisticated automotive applications bring unique test demands. Advanced ICs for applications such as highly integrated automatic braking system (ABS) and airbag controllers combine high voltage digital channels, significant VI demands and precise timing capability. Along with continued missioncritical reliability concerns, the trend toward higher voltage operation and increased device integration requires specialized test capabilities able to extend across the wide operating ranges found in automotive applications. Among these capabilities, automotive test requirements increasingly dictate a need for a cost-effective versatile mixed-signal pin electronics with very high data rates reaching up to 50MHz with a voltage swing of-2 V to +28 V.     

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.     

Optical vibration and deviation measurement of rotating machine parts

It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer （LDV）.