Scanning acoustic microscopy in porous SiC

被引：0

作者：

Ostapenko, S. ^{[1
]}

Smith, M.C.D. ^{[2
]}

Tarasov, I. ^{[1
]}

Wolan, J.T. ^{[1
]}

Mynbaeva, M. ^{[3
]}

Goings, J. ^{[4
]}

McKeon, J.C.P. ^{[4
]}

Saddow, S.E. ^{[1
]}

机构：

[1] Center for Microelectronics Research, University of South Florida, Tampa, FL 33620, United States

[2] Emerging Materials Research Laboratory, Dept. of ECE, Mississippi State, MS 39762, United States

[3] Ioffe Institute, RU-194021 St.-Petersburg, Russia

[4] Sonix, Inc., 8700 Morrissette Drive, Springfield, VA 22152, United States

来源：

Materials Science Forum | 2002年 / 389-393卷 / 01期

关键词：

Acoustic microscopes - Acoustic properties - Acoustic wave propagation - Epitaxial films - Silicon wafers - Ultrasonics;

D O I：

10.4028/www.scientific.net/msf.389-393.687

中图分类号：

学科分类号：

摘要：

We report on ultrasonic investigations of acoustic pulses propagating through both the porous surface regions and overgrown epitaxial films on both as-received and porous SiC wafers. In this study, n-type 6-H SiC(0001)Si 3.5° off-axis substrates were half-masked during anodization so that an epitaxial layer may be grown directly on both conventional and porous substrates for comparison purposes. [1]. The research goal of this work is to investigate the suitability of Scanning Acoustic Microscopy (SAM) for use in non-destructive assessment of porous structure in SiC crystals. Both transmission and reflection measurements were made on two crystals containing a 3 and 12 μm thick porous layer respectively. SAM involves the use of peak amplitude and time-of-flight information acquired while raster-scanning over a sample, to produce horizontal cross section images. One of important SAM features is a possibility to perform Tomographic Acoustic Micro Imaging (TAMI) where the entire image can be split into individual cross-sectional scans, analogous to physical sectioning of the sample. SAM in the TAMI mode was performed at an operating frequency up to 260MHz in the pulse-echo mode. A reduction in the absorption of high-frequency acoustic pulses by 25 to 35% was observed in the porous region compared with the control. This result also persists after epi-layer growth on porous SiC. © 2002 Trans Tech Publications.

引用

页码：687 / 690