Si衬底上外延3C-SiC薄层的XPS分析

采用HFCVD技术,通过两步CVD生长法,以较低生长温度,在Si(111)和Si(100)衬底上同时外延生长3C-SiC获得成功.生长源气为CH4+SiH4+H2混合气体,热丝温度约为2000℃,碳化和生长时基座温度分别为950℃和920℃,用X射线衍射(XRD)和X射线光电子能谱(XPS)等分析手段研究了外延层的晶体结构、组分及化学键能随深度的变化.XRD结果显示出3C-SiC薄层的外延生长特征,XPS深度剖面图谱表明薄层中的组分主要为Si和C,且Si/C原子比符合SiC的理想化学计量比,其三维能谱曲线进一步证明了外延层中Si2p和与Cls成键形成具有闪锌矿结构的3C-SiC.     

外延生长6H-SiC/Si薄膜的微结构研究

采用 Si H4 -C3H8-H2 气体反应体系 ,通过 APCVD工艺在 Si(1 0 0 )衬底上进行 Si C薄膜生长时 ,严格控制缓冲层生长的工艺条件 ,即 1 3 0 0°C碳化温度较高的 C3H8饱和浓度 ,可以获得结晶质量良好的 6H-Si C单晶外延层。利用 SEM、X射线衍射能谱 (XRD)及光致发光谱 (PL)分析了薄膜微结构并讨论了其微观机制     

硅熔体中3C-SiC的生长及6H-SiC晶型的抑制

论述了从硅熔体中生长 3C- Si C晶体过程中 6 H- Si C晶型控制的一般原理 .采用将硅置于高纯石墨坩埚中使其在高温条件下熔化 ,坩埚内壁石墨自然熔解于硅熔体中形成碳饱和的硅熔体 ,在石墨表面形成厚约 0 .2 m m的Si C薄层 .X射线衍射 (XRD)、X射线光电子能谱 (XPS)、Ram an散射等分析表明所制备样品为 3C- Si C多晶体 .实验结果进一步证明从硅熔体中生长 3C- Si C晶体过程中 ,通过适当调整工艺参数可以抑制 6 H- Si C晶型的形成 .     

Si1-x Gex:C缓冲层的生长温度对Ge薄膜外延生长的影响

用化学气相淀积方法,在Si(100)衬底上生长Si1-x Gex:C合金作为缓冲层、继而外延生长了Ge晶体薄膜,用X射线衍射(XRD)、俄歇电子能谱(AES)、拉曼(Raman)衍射光谱等对所得到的样品进行了表征测量,着重研究了Si1-x Gex:C缓冲层生长温度对样品结构特征的影响.结果表明:Si1-x Gex:C缓冲层中的Ge原子浓度沿表面至衬底方向逐渐降低,其平均组分随着生长温度的升高而降低.这与较高生长温度(760～820℃)所导致的原子扩散效应相关;在Si1-x Gex:C缓冲层上外延生长的Ge薄膜具有单一的晶体取向,薄膜的晶体质量随着温度的升高而降低.     

Si(111)碳化层中的SiC结晶

为采用HFCVD技术在Si（111）衬底上外延3C－SiC薄层而在Si表面首先进行碳化处理．实验样品用H2稀释的碳化物气氛进行碳化处理，热丝温度约为2000℃，衬底温度在950℃到1100℃之间．用X射线衍射、电子衍射和俄歇能谱等分析手段研究了碳化层的组分及结构，发现碳化层可由合碳硅结晶层、3C－SiC结晶层和富碳的3C－SiC结晶层组成．适当控制碳化条件可以调整3C－SiC结晶层的比例．     

硅基3C-SiC的热氧化机理

采用低压化学气相沉积(LPCVD)方法在Si(100)衬底上外延生长3C-SiC.利用干氧氧化方法对生长的SiC层进行了热氧化,氧化温度为1050℃.采用X射线光电子能谱仪(XPS),结合Ar+溅射技术,在不同的溅射时间下,对氧化生长的SiO2层及SiO2/SiC界面层的化学键和组成成分进行了深度谱分析,在此基础上提出了热氧化模型,探讨了3C-SiC的热氧化机理.     

低能离子束方法制备重掺杂Fe的Si∶Fe固溶体

利用质量分离的低能离子束方法,以离子能量为1 0 0 0 e V,剂量为3×1 0 1 7cm- 2 ,室温下往p型Si(1 1 1 )单晶衬底注入Fe离子,注入的样品在4 0 0℃真空下进行热处理.俄歇电子能谱法(AES)对原位注入样品深度分析表明Fe离子浅注入到p型Si单晶衬底,注入深度约为4 2 nm.X射线衍射法(XRD)对热处理样品结构分析发现只有Si衬底的衍射峰,没有其他新相.X射线光电子能谱法(XPS)对热处理样品表面分析发现Fe2 p束缚能对应于单质Fe的峰,没有形成Fe的硅化物.这些结果表明重掺杂Fe的Si∶Fe固溶体被制备.电化学C- V法测量了热处理后样品载流子浓度随深度的分布,发现Fe重     

硅基3C-SiC的热氧化机理

采用低压化学气相沉积(LPCVD)方法在Si(100)衬底上外延生长3C-SiC.利用干氧氧化方法对生长的SiC层进行了热氧化,氧化温度为1050℃.采用X射线光电子能谱仪(XPS),结合Ar 溅射技术,在不同的溅射时间下,对氧化生长的SiO2层及SiO2/SiC界面层的化学键和组成成分进行了深度谱分析,在此基础上提出了热氧化模型,探讨了3C-SiC的热氧化机理.     

6H-SiC同质外延层上Si1-yCy合金的生长

用化学气相淀积(CVD)的方法, 在6H-SiC衬底上同质外延生长SiC层, 继而外延生长了Si1-yCy合金薄膜, 用X射线衍射(XRD)、扫描电子显微镜(SEM)、拉曼散射等方法对所得的样品进行了表征测量, 着重研究了生长得到的Si1-yCy合金的晶体结构。SEM结果显示6H-SiC外延层上生长的Si1-yCy合金薄膜表面平整, 晶粒大小均匀; XRD衍射谱仅显示单一的特征衍射峰(2θ约为28.5°), 表明得到的合金薄膜晶体取向单一, 其晶体类型为4H型; 粗略估算, 合金薄膜中C含量约为3.7%。拉曼谱显示：随生长气源中的C/Si比的增加, Si1-yCy合金薄膜中替位式C含量逐渐增大, 当C/Si比达到一定值时, 合金薄膜中有间隙式C出现, 造成晶体缺陷, Si1-yCy合金薄膜晶体质量下降。     

低温生长SiC薄膜衬底碳化研究

讨论了在用热丝化学汽相沉积(HFCVD)法沿Si(111)晶面异质生长SiC薄膜的过程中衬底碳化工艺对SiC成膜的影响。利用扫描电子显微镜(SEM)、X射线衍射谱(XRD)、透射电子显微镜(TEM)和俄歇电子能谱(AES)等分析手段,对衬底碳化进行研究。并对典型工艺条件(钨丝温度2 000℃,衬底温度800℃,衬底碳化时间5 min)下制备的样品的碳化层进行分析,得出其厚度约为20 nm,由富C的3C-SiC层,3C-SiC层和含C的Si层组成。     

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。     

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.     

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）.     

社长序言（英文）

正Happy New Year!As we step into a new year,we take a look back at the key feature topics covered in China Communications over the past 12 months and set out our expecta-     

Call for Papers

正Introduction Jointly sponsored by the China Institute of Communications(CIC)and the IEEE Communications Society(IEEE ComSoc)since the year 2013,China Communications,currently,is aiming to gradually realise the transition from journal to magazine content and style.     

INTEGRATION OF OPTICAL AND WIRELESS NETWORKS

正For a long time,optical and wireless systems/net-works are developed in separate communities witha few attempts for in-depth convergence.In fact,it prom-ises many advantages to combine the optical and wire-less technologies in the levels of systems and networks.Recently,both academia and industry have made manyefforts to enter a new phase of development to take op-tical and wireless systems as fully integrated networks.To provide high bandwidth and reliable service for bothfixed and mobile users,a well-designed network must     

Call for Papers—Feature Topic,Vol.12,No.3,2015

正Smart Grid Communications The electric power industry is undergoing profound changes as the industry aims to capture the promise of a smart grid for a sustainable energy future.Enabled by the advanced sensing devices such as Phasor Measurement Units(PMUs),increasingly powerful