In Situ X-Ray Measurements of Defect Generation during PVT Growth of SiC

Konias, Katja; Hock, Rainer; Stockmeier, Matthias; Wellmann, Peter J.; Miller, Matthew; Ossege, S.; Magerl, A.

doi:10.4028/www.scientific.net/msf.556-557.267

Cited by 8 publications

(9 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…One-dimensional beam focusing of hard X-rays by crystals in Laue transmission geometry has been described earlier (Guinier & Tennevin, 1949) and it is being used increasingly for material analysis (Stockmeier et al, 2005;Konias et al, 2007). The method presented here is an extension to a twodimensional focusing with the aim to develop a novel concept for a small-angle diffractometer for high-energy X-rays.…”

Section: Discussionmentioning

confidence: 99%

Two-dimensional focusing of high-energy X-rays by thermal-gradient crystals for small-angle X-ray scattering

2008

Self Cite

View full text Add to dashboard Cite

A novel method for focusing X-rays in two dimensions by thermal-gradient crystals in symmetrical Laue geometry is described. A 225 kV stationary tungsten tube delivers an X-ray beam with a source diameter of about 1.0 mm (full width at half-maximum). The focal point at the detector at a distance up to 16 m from the source is of the same size. The beam at the focusing crystals at half the distance between the source and the detector has typical dimensions of 30 Â 30 mm. The intensity of the focal point can be increased by more than 200 times by applying a thermal gradient of about 2.2 K mm À1 on the focusing crystals. The described method and apparatus are designed for small-angle X-ray scattering at high photon energies up to 60 keV, where the high penetration power allows experiments on strongly absorbing materials in transmission mode. Particle sizes up to 3000 Å can be detected. First measurements on nanocrystalline tungsten carbide and Teflon yield radii of gyration of 540 Å and 815 Å , respectively.

show abstract

Section: Discussionmentioning

confidence: 99%

Two-dimensional focusing of high-energy X-rays by thermal-gradient crystals for small-angle X-ray scattering

2008

Self Cite

View full text Add to dashboard Cite

show abstract

“…To trace the SiC resublimation paths and to link it with numerical modeling of the growth process, Si 13 C was added to the bottom of Si 12 C powder source . Experiments that include in situ X‐ray diffraction during PVT growth have been reported in .…”

Section: Growth Process Visualizationmentioning

confidence: 99%

“…It was experimentally shown that p‐type SiC crystal boules systematically exhibit a reduced basal plane dislocation density which is beneficial for bipolar SiC electronic devices. Although not completely understood from fundamental growth theory, the electronic properties of p‐type SiC, in particular the position of the Fermi energy below the band gap center, have been attributed to the reduction of the basal plane dislocation density .…”

Section: Dopingmentioning

confidence: 99%

Growth of SiC bulk crystals for application in power electronic devices – process design, 2D and 3D X‐ray in situ visualization and advanced doping

Wellmann

Neubauer

Fahlbusch

et al. 2014

Crystal Research and Technology

View full text Add to dashboard Cite

Silicon carbide single crystals have become widely used as substrates for power electronic devices like diodes and electronic switches. Today, 4inch and 6inch wafer diameters are commercially available which are processed from vapor grown crystals. The state of the art physical vapor transport method may be called mature. Nevertheless, low defect density and uniform doping are still topics which can be further improved by current research and development of more sophisticated processes and process control. The aim of the paper is to review the physical vapor transport growth method as applied today. Special emphasis will be put on currently less advanced in situ growth monitoring tools based on 2D and 3D X-ray imaging that could be a tool for production monitoring. These techniques allow a precise determination of the crystal and source material evolution. Another topic will be the processing of highly conductive p-type 4H-SiC which is of particular interest for power electronic switches

show abstract

“…The application of X-ray technology at our department for in-situ visualization of the SiC crystal in the PVT reactor has lead in recent years to several important results on mass transport, polytype switching and defect generation. There are several publications about gaining 2-D X-ray radiography and X-ray diffraction images from the crystal during growth [1][2][3][4][5], which improved the basic understanding of silicon carbide crystal growth. Based on past research, our goal is to significantly improve the image quality by using 3-D X-ray computed tomography.…”

Section: Introductionmentioning

confidence: 99%

Real-Time Measurement of the Evolution of Growth Facets during SiC PVT Bulk Growth Using 3-D X-Ray Computed Tomography

Neubauer

Salamon

Uhlmann

et al. 2014

MSF

Self Cite

View full text Add to dashboard Cite

In this paper, we present our new setup and technique for obtaining a real-time 3-D volume shape of the SiC crystal using X-ray computed tomography (CT). Hence, it is possible to determine in-situ the shape of the growth interface with high precision at growth temperatures above 2000 °C in a conventional 3" physical vapor transport (PVT) growth system. We show that the size and shape of a facet can be monitored at different stages during growth and furthermore the crystals face boundary can be determined with high precision throughout the whole growth process.

show abstract

In Situ X-Ray Measurements of Defect Generation during PVT Growth of SiC

Abstract: All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of Trans Tech Publications Ltd, www.scientific.net.

Cited by 8 publications

References 0 publications

Two-dimensional focusing of high-energy X-rays by thermal-gradient crystals for small-angle X-ray scattering

Two-dimensional focusing of high-energy X-rays by thermal-gradient crystals for small-angle X-ray scattering

Growth of SiC bulk crystals for application in power electronic devices – process design, 2D and 3D X‐ray in situ visualization and advanced doping

Real-Time Measurement of the Evolution of Growth Facets during SiC PVT Bulk Growth Using 3-D X-Ray Computed Tomography

Contact Info

Product

Resources

About