扫描电声显微镜成像技术研究

扫描电声显微镜(scannmg electron acoustic microscoPe)问世以来，作为一种新的显微成像手段，在众多的材料研究领域得到了广泛的应用，并日益显露其独特的成像本领。为此，我们对原建立的SEAM系统，通过增强电子束流强度和改善调制电路，使得系统的信噪比和空间分辨率大为提高。     

扫描探针声显微镜原理及其应用

将声学检测技术与扫描探针显微术相结合,构成的扫描探针声显微镜,不仅可以检测材料表面、亚表面和内部的微小缺陷,还可以分析样品的弹性特性、电特性等物理性能,同时还具有分辨率高的特点,在材料科学和生命科学等领域具有很高的应用价值.目前,得到实际应用的扫描探针声显微镜主要有扫描隧道声显微镜和原子力声显微镜.本文介绍了这两类显微镜的基本工作原理,并对扫描探针声显微镜今后的发展方向进行了探讨.     

GaN薄膜电子声成像和电子背散射衍射研究

采用扫描电声显微镜(SEAM)和电子背散射衍射(EBSD)对异质外延在Al2O3衬底上GaN界面区域成像测试分析。异质外延失配应力导致在Al2O3和GaN界面附近的微区晶格畸变在SEAM的声成像中可以清楚看到,而且受应力影响集中区域的微区衬度差异明显。利用EBSD色带图及质量参数分析了失配应力变化,晶格应变和弹性形变在200nm内可以得到释放。     

2007电声技术国际研讨会四月召开

为了促进国内国际电声技术的交流发展，向国际高水平迈进，由南京大学声学研究所主办，中国声学学会声频工程分会、中国电子学会声频工程分会、中电元协电声器件分会、江苏省声学学会、《电声技术》杂志协办的“2007电声技术国际研讨会”[第一段]     

高速原子力显微术研究进展

自1986年发明原子力显微镜以来,它已成为材料、生物以及纳米科技等许多领域的重要工具。由于常规原子力显微镜成像速度缓慢,在动态过程观测、工业生产线原位测量以及高密度信息存储等领域的应用受到限制,因此发展高速原子力显微术近年来已引起国内外的高度关注。本文综述了高速原子力显微术关键技术(包括:微小探针、高速扫描器设计和控制方法)以及应用等方面的最近进展。     

半导和非半导性BaTiO_3陶瓷电声像衬度来源的差异

利用ＳＥＡＭ技术对半导和非半导性的ＢａＴｉＯ３陶瓷材料进行了电声成像观察研究．在半导性的这种材料电声成像中，由于掺杂的作用削弱和屏蔽了样品本身电学性能参数变化对电声像衬度的贡献，使得热波耦合机制起到主要作用；在非半导性的这种材料电声成像中，其电学性能参数的变化决定了电声像衬度的不同．     

磁共振力显微镜

磁共振力显微镜是磁共振成像技术与扫描探针显微术的成功结合,它同时具备了磁共振成像的三雏探测能力与扫描探针显微术的纳米分辨能力.与传统的感应式磁共振信号探测方法相比,磁共振力显微镜的最大优势在于它采用的机械力学磁共振信号探测方法具有极高的信噪比,可以满足单个核自旋探测的要求.自1991年华盛顿大学的Sidles教授首次提...     

基于STM的多模式扫描探针显微镜的建立

在已有的扫描隧道显微镜（STM）基础上设计了一套集STM、 光子扫描隧道显微镜（PSTM）、近场扫描光学显微镜（NSOM）、扫描近场声学显微镜（SNAM）为一体的多模式扫描探针显微系统（SPM）。系统的4种模式可通过转换开关方便地切 换,探头的更换也很容易。利用本系统对典型样品进行了扫描成像。测试表明,系统具有良好的稳定性和超高分辨率。     

IEAT 2007 电声技术国际研讨会

经过长时间的筹办，由南京大学声学研究所主办，中国声学学会声频工程分会、中国电子学会声频工程分会、中电元协电声器件分会、江苏省声学学会、《电声技术》杂志协办的《2007电声技术国际研讨会》深圳会场于4月7日在深圳市的虚拟大学园正式开幕，来自海内外的知名专家学者、资深工程师、高级管理人员等数百名来宾参加了会议。     

IEAT2007电声技术国际研讨会在深圳和南京召开

2007电声技术国际研讨会（2007 International Elec tro Acoustic Technology,Symposia，IEAT2007）于2007年4月7～8日、4月10～11日分别在深圳市虚拟大学园、南京市南京大学召开。会议由南京大学声学研究所主办，中国声学学会声频工程分会、中国电子学会声频工程分会、中电元协电声器件分会、江苏省声学学会、深圳市三诺科技发展有限公司和《电声技术》杂志协办，南京大学声学研究所音频声学实验室、南京大学深圳研究院、南京大学近代声学重点实验室深圳研发中心承办。     

电子显微镜的现状与展望

本文扼要介绍了电子显微镜的现状与展望，透射电子显微镜方面主要有：高分辨电子显微学及原子像的观察，像差校正电子显微镜，原子尺度电子全息学，表面的高分辨电子显微正面成像，超高压电子显微镜，中等电压电镜，１２０ｋＶ，１００ｋＶ分析电镜，场发射枪扫描透射电镜及能量选择电镜等，透射电镜将又一次面临新的重大突破，扫描电子显微镜方面主要有：分析扫描电镜和Ｘ射线能谱仪，Ｘ射线波谱仪和电子探针仪，场发射枪扫描电镜和     

Scanning optical microscopes close in on submicron scale

The principles and advantages of the confocal scanning optical microscope (CSOM) are described, and the history of the concept is given. The CSOM is compared with the scanning electron microscope, scanning acoustic microscope, scanning tunneling microscope, scanning force microscope, and near-field scanning optical microscope. The imaging properties and applications of the CSOM are discussed     

声显微成像

简要介绍激光扫描声学显微镜、机械扫描声学显微镜、Ｃ模型扫描声学显微镜的工作原理、结构和特性，并对在电子工业中的应用进行了讨论。激光扫描声学显微镜，机械扫描声学显微镜，Ｃ模型扫描声学显微镜     

A high-sensitivity real-time acoustic imaging system for biomedical diagnosis

A real-time acoustic imaging system which is essentially the acoustic equivalent of the scanning electron-beam microscope is proposed. This system with piezoelectric detection is superior in theoretical performance to all the presently existing systems. A possible embodiment of such a system is described.     

SAM扫描器件芯/焊结合空洞的失效分析

超声无损检测是70种无损探伤技术的最热点。扫描声学显微镜(SAM)的原理是声阻抗成像,要求缺陷尺度大于超声波的波长。结合SAM技术中的A-扫描波形分析和C-扫描特征成像,针对由封装引入的分层和空洞缺陷进行失效分析。研究发现:分层定位的关键是A-扫描波形分析中对各界面处反射波的时间位置的判断;基于分层定位的芯/焊结合空洞缺陷的判别,关键是C-扫描图像中灰阶色带的区分(反射率差值)。     

Environmental Qualification Testing and Failure Analysis of Embedded Resistors

Embedding passive components (capacitors, resistors, and inductors) within printed wiring boards (PWBs) is one of a series of technology advances enabling performance increases, size and weight reductions, and potentially economic advantages in electronic systems. This paper explores the reliability testing and subsequent failure analysis for laser-trimmed Gould subtractive nickel chromium and MacDermid additive nickel phosphorous embedded resistor technologies within a PWB. Laser-trimmed resistors that have been “reworked” using an inkjet printing process to add material to their surface to reduce resistance have also been considered. Environmental qualification testing performed included: thermal characterization, stabilization bake, temperature cycling, thermal shock and temperature/humidity aging. In addition, a pre/post-lamination analysis was performed to determine the effects of the board manufacturing process on the embedded resistors. A failure analysis consisting of optical inspection, scanning acoustic microscope (SAM) and environmental scanning electron microscope (ESEM) imaging, and PWB cross-sectioning was employed to determine failure mechanisms. All the embedded resistors were trimmed and the test samples included resistors fabricated both parallel and perpendicular to the weave of the board dielectric material. Material stability assessment and a comparison with discrete resistor technologies was performed.     

Failure analysis of solder bumped flip chip on low-cost substrates

Failure analyses of 63/37 Sn/Pb solder bumped flip chip assemblies with underfill encapsulant are presented in this study, Emphasis is placed on solder flowed-out, nonuniform underfill and voids, and delaminations. The X-ray, scanning acoustic microscope (SAM), and tomographic acoustic micro imaging (TAMI) techniques are used to analyze the failed samples. Also, cross sections are examined for a better understanding of the failure mechanisms. Furthermore, temperature dependent nonlinear finite element analyses together with fracture mechanics are used to determine the effects of underfill void sizes on the flip chip solder joint reliability     

Application of nano-diffraction to local atomic distribution function analysis of amorphous materials

A method is proposed for the local atomic distribution function analysis of amorphous materials. This method is based on local halo-electron diffraction intensity analysis with nano-sized electron probes as small as 25 to approximately 3 nm, taking advantage of the intensity recording with imaging plate. Nanodiffraction and selected area electron diffraction (SAED) patterns from an amorphous SiNx (x approximately 4/3) thin film were taken using a conventional transmission electron microscope operated at 200 kV and recorded on imaging plates. An intensity correction to omit inelastic intensity was made using electron energy-loss spectroscopy. When a beam-convergence angle is larger than 1 x 10(-3) rad, the Wiener-filter deconvolution method becomes helpful in producing atomic pair distribution functions (PDFs) from the nano-diffraction intensity profiles that are more similar to the PDF from the SAED intensity. This technique was applied to the analysis of local amorphous structures of SiO2 layers formed by an oxygen-ion implantation into single crystal SiC.