Chemistry of inorganic compounds – Silicon or compound thereof – Binary compound
Patent
1999-02-03
2000-11-28
Utech, Benjamin L.
Chemistry of inorganic compounds
Silicon or compound thereof
Binary compound
117 4, 117 7, 117 8, 117 9, 117 84, 117 88, 117951, C30B 104, C30B 2936
Patent
active
061531669
DESCRIPTION:
BRIEF SUMMARY
CROSS REFERENCE TO RELATED APPLICATIONS
This application discloses subject matter in common with application, No. 09/147,620, filed Feb. 13, 1999.
TECHNICAL FIELD
The present invention relates to single crystal SiC and a method of producing the same, and more particularly to single crystal SiC which is used as a substrate wafer for a high temperature semiconductor electronic element such as a light-emitting diode, an X-ray optical element, a switching element, an amplifying element, and an optical sensor, and also to a method of producing the same.
BACKGROUND ART
SiC (silicon carbide) is superior in heat resistance and mechanical strength to existing semiconductor materials such as Si (silicon) and GaAs (gallium arsenide), and has good resistance to radiation. In addition, it is easy to perform valence control of electrons and holes by doping an impurity. Moreover, SiC has a wide band gap (for example, single crystal 6H-SiC has a band gap of about 3.0 eV, and single crystal 4H-SiC has a band gap of 3.26 eV). Therefore, it is possible to realize a large capacity, high-frequency property, dielectric property, and environmental resistance which cannot be realized by existing semiconductor materials. SiC is receiving attention and is expected as a semiconductor material for a next-generation power device.
As a method of producing (growing) single crystal SiC of this type, known are a method in which single crystal SiC is grown by a sublimation and recrystallization method using a seed crystal, and that in which, in the case of a high temperature, epitaxial growth is conducted on a silicon substrate by using a chemical vapor deposition method (CVD method), thereby growing single crystal cubic SiC (.beta.-SiC).
In the above-described conventional production methods, however, the crystal growth rate is as low as 1 .mu.m/hr. Furthermore, the sublimation and recrystallization method has a problem in that pin holes which have a diameter of several microns and which pass through the crystal in the growing direction remain at about 100 to 1,000/cm.sup.2 in a growing crystal. Such pin holes are called micropipe defects and cause a leakage current when a semiconductor device is fabricated. These problems block a practical use of single crystal SiC which has superior characteristics as compared with other existing semiconductor materials such as Si and GaAs as described above.
In the case of the high-temperature CVD method, the substrate temperature is as high as 1,700 to 1,900.degree. C., and it is required to produce a high-purity reducing atmosphere. Therefore, the method has a problem in that it is difficult to conduct the method from the view point of installation. Furthermore, the method has another problem in that, because of epitaxial growth, the growth rate is naturally limited.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide large single crystal SiC of high quality which has a reduced number of micropipe defects and the like, and a method of producing single crystal SiC which can produce such large single crystal SiC of high quality easily and efficiently from the view point of installation and workability, and which can expedite the practical use of the single crystal as a semiconductor material.
The single crystal SiC of the present invention is characterized in that a complex in which a single crystal SiC base material and a polycrystalline plate consisting of Si and C atoms are stacked together via a smooth face is subjected to a heat treatment, whereby polycrystals of the polycrystalline plate are transformed into a single crystal.
According to this configuration, polycrystals of the polycrystalline plate are phase-transformed by only applying means which thermally processes a complex consisting of a single crystal SiC base material and a polycrystalline plate that are stacked together, and which is simple from the view point of installation and workability, so that a single crystal is efficiently grown. Since the single crystal SiC base material and the polycrystalli
REFERENCES:
patent: 4565584 (1986-01-01), Tamura et al.
patent: 4578143 (1986-03-01), Arai
patent: 4590130 (1986-05-01), Cline
patent: 4738935 (1988-04-01), Shimbo et al.
patent: 5100839 (1992-03-01), Terao
patent: 5471946 (1995-12-01), Scholz et al.
patent: 6053973 (2000-04-01), Tanino et al.
Champagne Donald L.
Nippon Pillar Packing Co. Ltd.
Utech Benjamin L.
LandOfFree
Single crystal SIC and a method of producing the same does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Single crystal SIC and a method of producing the same, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Single crystal SIC and a method of producing the same will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1721940