用氧化多孔硅方法制备厚的Si02膜及其微观分析

用氧化多孔硅的方法来制备厚的SiO2成本低,省时.氧化硅膜的厚度,表面粗糙度和组分这三个参数,对波导器件的性能有重要影响,扫描电子显微镜(SEM)、原子力显微镜(AFM)和俄歇分析得到：氧化的多孔硅的膜厚已达21.2μm;表面粗糙度在1nm以内,Si和O的组分比为1:1.906.这些结果表明,用氧化多孔硅方法制备的厚SiO2膜满足低损耗光波导器件的要求.     

用氧化多孔硅方法制备厚的SiO_2膜及其微观分析

用氧化多孔硅的方法来制备厚的 Si O2 成本低 ,省时 .氧化硅膜的厚度 ,表面粗糙度和组分这三个参数 ,对波导器件的性能有重要影响 ,扫描电子显微镜 ( SEM)、原子力显微镜 ( AFM)和俄歇分析得到 :氧化的多孔硅的膜厚已达 2 1 .2μm;表面粗糙度在 1 nm以内 ,Si和 O的组分比为 1∶ 1 .90 6.这些结果表明 ,用氧化多孔硅方法制备的厚 Si O2 膜满足低损耗光波导器件的要求     

用于微波/射频集成电路的一种新型低损耗介质——多孔硅及氧化多孔硅厚膜

提出在单片微波集成电路(MMIC)中用多孔硅/氧化多孔硅厚膜作微波无源器件的低损耗介质膜.研究了厚度为70μm的多孔硅/氧化多孔硅厚膜在低阻硅衬底上的形成,这层厚膜增加了衬底的电阻率,减少了微波的有效介质损耗.通过测量在低阻硅衬底上形成的氧化多孔硅厚膜上的共平面波导的微波特性,证明了在低阻硅衬底上用厚膜氧化多孔硅可以提高共平面传输线(CPW)的微波特性.     

用于微波/射频集成电路的一种新型低损耗介质——多孔硅及氧化多孔硅厚膜

提出在单片微波集成电路(MMIC)中用多孔硅/氧化多孔硅厚膜作微波无源器件的低损耗介质膜.研究了厚度为70μm的多孔硅/氧化多孔硅厚膜在低阻硅衬底上的形成,这层厚膜增加了衬底的电阻率,减少了微波的有效介质损耗.通过测量在低阻硅衬底上形成的氧化多孔硅厚膜上的共平面波导的微波特性,证明了在低阻硅衬底上用厚膜氧化多孔硅可以提高共平面传输线(CPW)的微波特性.     

新型湿法氧化对多孔硅发光强度的影响

在适当条件下氧化多孔硅是提高多孔硅发光强度的良好途径。首次采用含CH3CSNH2的HF酸水溶液作为氧化剂对初始多孔硅进行了湿法阳极氧化,大大改善了多孔硅的发光强度,并研究了氧化电流密度、氧化温度、氧化时间等一系列因素对氧化多孔硅光致发光强度的影响。实验发现,在电流密度1mA/cm^2,氧化液温度60℃,氧化时间为10min的条件下,可以获得最强光致发光;在此最优条件下得到的氧化样品较初始样品发光增强了18倍。     

脉冲腐蚀法制备多孔硅及其光学特性研究

Labview软件控制腐蚀条件,用脉冲电化学腐蚀法制备多孔硅薄膜,其表面形貌用原子力显微镜观察并分析。用可见-紫外分光光度仪测量其反射谱,通过计算得出各种制备条件下,多孔硅薄膜的其它光学参数,即有效折射率neff,吸收系数α,有效介电常数的实部εer,和虚部εei,消光系数K,研究了入射光波长和孔隙率对这些光学常数的影响。     

脉冲腐蚀法制备多孔硅及其光学特性研究

Labview软件控制腐蚀条件,用脉冲电化学腐蚀法制备多孔硅薄膜,其表面形貌用原子力显微镜观察并分析。用可见-紫外分光光度仪测量其反射谱,通过计算得出各种制备条件下,多孔硅薄膜的其它光学参数,即有效折射率neff,吸收系数α,有效介电常数的实部εer和虚部εei,消光系数K。研究了入射光波长和孔隙率对这些光学常数的影响。     

Effective Crosstalk Isolation With Post-CMOS Selectively Grown Porous Silicon Technique for Radio Frequency System-on-Chip (SOC) Applications

In this letter, post-CMOS substrate selective-transformation engineering based on the selectively grown porous silicon (SGPS) technique is demonstrated to effectively suppress substrate crosstalk. The testing structures for crosstalk isolation are fabricated in a standard 0.18-$muhbox{m}$ CMOS process, and porous silicon trenches are selectively grown after processing from the backside of the silicon wafer. For a testing structure with 250-$muhbox{m}$ separation on Si, a 42.8-dB improvement (from $-$23.5 to $-$66.3 dB) for crosstalk isolation is achieved at 2 GHz. The characteristics of the SGPS substrate have been extracted using the conventional lump element model, which shows that our SGPS technique increases the substrate impedance by one order of magnitude. These results demonstrate that our post-CMOS substrate selective-transformation engineering is very promising for radio frequency system-on-chip applications.      

Formation of Luminescent Silicon Nanowires and Porous Silicon by Metal-Assisted Electroless Etching

Metal-assisted etching of silicon in HF/H₂O₂ aqueous solutions has been used to fabricate luminescent silicon nanowires (SiNWs) and porous silicon. The impact of the gold catalyst layer thickness and the etching solution on the morphology of the synthesized nanostructures and the diameter of the obtained nanowires were systematically investigated. Scanning electron microscopy (SEM) analyses reveal that the morphology of the fabricated structures strongly depends on the composition of the solution and the thickness of the catalyst layer. It has been observed that SiNWs are formed in solutions with H₂O₂ ratios (ξ) below 10 %; increasing the H₂O₂ concentration above this critical value leads to mesoporous (10 % < ξ < 14 %) and macroporous (14 % < ξ < 17 %) structures. Photoluminescence measurements show that SiNWs emit light at about 430 nm. Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM) analyses were utilized to determine the origin of the emission in the silicon nanostructures. TEM imaging demonstrates that SiNWs are covered by a thin layer of porous silicon, which is assumed to be responsible for their light emission.     

Surface-free technology by laser annealing (SUFTLA) and its application to poly-Si TFT-LCDs on plastic film with integrated drivers

In order to realize electronic devices on plastic film, new technology has been developed that enables the transfer of thin-film devices from an original substrate to another substrate by using laser irradiation. This technology was termed SUFTLA, which stands for surface-free technology by laser annealing. A polycrystalline-silicon thin film transistor (poly-Si TFT) back-plane for liquid crystal displays (LCDs) with integrated drivers was fabricated using a low-temperature process (below 425/spl deg/C) and could be successfully transferred from a glass or quartz substrate to plastic film using this technology. This technology enabled us to fabricate an all-plastic substrate TFT-LCD having a display area of 0.7 in measured diagonally and a pixel count of 428/spl times/238. In addition, the operation of the integrated drivers and the displayed image could be confirmed for the first time in the world.     

Simox technology and its application to CMOS LSIS

SIMOX technology has been developed for fabricating SOI-type devices. In this technology, buried silicon oxide is used for the vertical isolation of semiconductor devices. The buried oxide is formed by oxygen-ion implantation into silicon, followed by epitaxial growth of silicon onto the surface of the residual silicon above the buried oxide. The crystallinity of the residual silicon was investigated by electron beam diffraction, while the implanted oxygen depth profile was analyzed by Rutherford backscattering spectroscopy. A 1Kb CMOS static RAM has been fabricated using polysilicon gate SIMOX technology with a 1.5μm effective channel length. The chip-select access time of the RAM was 12ns at 45mW dissi-pation power.     

Simplified bipolar technology and its application to systems

Base-diffusion isolation with a buried collector simplifies the fabrication of very-high-speed circuits. Base-diffusion isolation with a buried collector simplifies the fabrication of very-high-speed circuits. Base-diffusion isolation without a buried collector permits the fabrication of circuits with no more processing than is needed for a discrete planar transistor. Packing densities of these transistors are similar to those of IGFETs. Functional packing densities will depend upon the particular circuit used. The new structures should permit fabrication of many circuits with the performance advantages of bipolar devices at costs comparable to those of IGFETs. To exploit these devices to the best advantage low-voltage logic is required. Studies of an exploratory digital system using gates operated from a 2-V supply have shown the feasibility of such an approach.     

OEIC technology and its application to subscriber loops

Recent progress in GaAs- and InP-based optoelectronic integrated circuits (OEICs) for use in optical fiber transmission systems is reviewed. OEIC technology and system demonstrations for short-haul and high-speed transmission are described, and the problems arising in practical applications are discussed. Approaches to resolution of these problems are presented, and future OEIC applications, especially with regard to subscriber loops, are predicted     

频率选择表面及其在隐身技术中的应用

频率选择表面(FSS)是一种二维周期性结构，可以有效地控制电磁波的反射与传输。本文介绍了它的基本概念、分析方法及其在不同电磁波段的应用，特别在导弹电子战中有着不可替代的应用。     

多孔硅/PVK复合体系的光电性能

用旋涂法实现了多孔硅与聚乙烯咔唑的复合，并研究了不同温度热处理后复合体系的电学和光学性能．实验结果表明：热处理有利于复合体系发光强度的提高；而且当热处理温度不超过120℃，随着热处理温度的升高器件的整流效应增大．同时，复合体系还实现了电致发光，产生了555nm的电致发光峰．     

多孔硅/PVK复合体系的光电性能

用旋涂法实现了多孔硅与聚乙烯咔唑的复合,并研究了不同温度热处理后复合体系的电学和光学性能.实验结果表明:热处理有利于复合体系发光强度的提高;而且当热处理温度不超过120℃,随着热处理温度的升高器件的整流效应增大.同时,复合体系还实现了电致发光,产生了555nm的电致发光峰.     

多孔硅的光电性质及在太阳能电池中的应用

论述了多孔硅电化学和化学的腐蚀机理以及多孔硅的光电性质,提出多孔硅在太阳能电池应用中存在的一些实际问题。     

浅谈WiMAX技术及其应用

简单论述了WiMAX的标准、关键技术及应用场景，展望了宽带移动通信的发展前景．并从无线管理的角度提出了几点思考。     

"SIS"技术与应用辨析谈

从系统应用的角度诠释一种用于扩声系统的设计理念——“SIS”(Spatim Image Systems,空间成像系统)。对它的原理、系统功能、组合方式与特点、技术要求与传统扩声系统的比较等做了分析,以使有关开发与应用人员能够准确了解“SIS”技术,更好地拓展该技术的使用。