SiC Crystal Growth from the Vapor and Liquid Phase
- PDF / 2,708,039 Bytes
- 14 Pages / 595 x 842 pts (A4) Page_size
- 28 Downloads / 298 Views
SiC Crystal Growth from the Vapor and Liquid Phase 1
2
Dieter Hofmann, Matthias Bickermann, Dirk Ebling , Boris Epelbaum, Lev Kadinski , 2 Markus Selder , Thomas Straubinger, Roland Weingaertner, Peter Wellmann and Albrecht Winnacker Department of Materials Science 6, University of Erlangen-Nuernberg, Martensstr. 7, D-91058 Erlangen, Germany 1 Freiburg Materials Research Center (FMF), University of Freiburg, Stefan-Meier-Str. 21, D-79104 Freiburg i. Br., Germany 2 Institute of Fluid Mechanics, University of Erlangen-Nuernberg, Cauerstr. 4, D-91058 Erlangen, Germany ABSTRACT The status of SiC vapor growth technique (PVT) is reviewed and related innovative aspects are introduced. Problems of the preparation of SiC crystals with uniform electronic properties are addressed, especially the growth of semiinsulating SiC. An overview about the performance of numerical modeling is given as tool for the optimization of the PVT process. Development activities in the field of liquid phase processing for the preparation of SiC bulk crystals and micropipe healing are presented. Finally recent results on the present understanding of filamentary void formation/elimination (micropipes, macrodefects) are summarized. INTRODUCTION During the last years impressible advances have been achieved in the development of SiC and III-nitide based device technology for electronic and optoelectronic applications [1]. A broad commercialization is already under way in the area of blue/UV optoelectronics. The production of SiC devices for power electronics, high frequency and high temperature electronics is just in the starting phase. A key parameter triggering the further development is the availability of suitable single crystalline SiC substrates of 4H and 6H polytype by a sufficient number of potential suppliers. “Suitable“ means in this context that the actual needs of device industry can be satisfied in terms of crystalline perfection (micropipe and dislocation density), uniformity of electronic properties, surface quality, wafer diameter and costs. The fact that several companies are now manufacturing and offer SiC wafers can be regarded as very positive situation although wafer quality and wafer supply capacity may be very different between the companies. Considerable advances have been attained during the last years in respect of reduction of micropipe density, surface quality and increase of wafer diameter. The available standard diameter of 2” allows obviously a reasonable production of optoelectronic devices (6H). Starting production activities in power electronics (4H substrate) are restricted to small area devices as micropipes limit still the effective application for high power (= large area device). Recently a director from the wide band gap semiconductor industry stated: “Further advance in SiC wafer quality remains now only a management problem“. But major research efforts are mandatory though, especially under aspects of high yield and low cost manufacturing. Genetically substrate wafer quality of less complex material systems
Data Loading...
