Meso-scale Nondestructive Observation System of Self-organized Dislocation Network using Scanning Electron Acoustic Microscopy

扫描电声显微镜自组织位错网络细观无损观测系统

基本信息

批准号：
12555028
负责人：
SHIBUTANI Yoji
金额：
$ 5.57万
依托单位：
Osaka University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2001
项目状态：
已结题

项目摘要

In order to investigate internal structures generated by self-organized dislocation network in various kinds of materials and loading states, we have developed a nondestructive observation system using acoustic wave by the electron beam. In this system, heat wave is firstly generated on the surface of the specimen by the irradiation of blanking and focused electron beam of the Scanning Electron Microscope (SEM). Then the heat wave is transferred into sound wave, and it propagates within the specimen as elastic wave. Difference of the local thermal property of the material is converted into an electric signal by a piezoelectric transducer (PZT) attached onto the back side of the specimen. This system is called the scanning electron acoustic microscopy (SEAM). It makes us enable to observe both the surface of the specimen by SEM mode and the nondestructive inside structure by SEAM. A commercial amplifier is not enough to detect the electric signals by the PZT, because these signals are very feeble and high frequency. We developed a newly head amplifier using transistors. This head amplifier transforms an impedance and amplifies the electric signals. And we used an instrumentation amplifier to eliminate the noises from detected signals. Then the detected signals are amplified by a lock-in amplifier synchronized to the blanking frequency of an electron beam. The performance of this developed head amplifier seems to be excellent and it makes us enable to detect the electron acoustic signals sufficiently.We obtained ultrasonic signal by the SEAM using the Diamond Like Carbon (DLC) thin film laminated on single crystalline silicon wafer. And we developed a portrayal system that draws these signals as two dimensional phase-contrast images on the display.

为了研究以各种材料和加载状态在自组织中产生的内部结构，我们使用电子束的声波开发了一种非破坏性观察系统。在该系统中，首先通过扫描电子显微镜（SEM）的空白和聚焦电子束的照射在样品表面产生热浪。然后将热浪传递到声波中，并以弹性波的形式在样品中传播。材料的局部热特性的差异通过连接到试样背面的压电传感器（PZT）转换为电信号。该系统称为扫描电子声学显微镜（接缝）。它使我们能够通过SEM模式观察样品的表面，并通过接缝观察非破坏性的内部结构。商业放大器不足以检测PZT的电信号，因为这些信号非常微弱且频率很高。我们使用晶体管开发了新的头部放大器。该头放大器会改变阻抗并放大电路。我们使用仪器放大器来消除检测到的信号中的噪音。然后，通过锁定放大器同步到电子束的掩体频率，将检测到的信号放大。该发达的头部放大器的性能似乎很棒，它使我们能够充分检测到电子声信号。我们使用钻石（如碳（DLC）薄膜）在单晶硅晶状体上叠放的钻石（DLC）薄膜获得了超声信号。我们开发了一个描绘系统，将这些信号绘制为显示屏上二维相位对比的图像。