The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 14, 2011
Filed:
Jun. 21, 2010
Koji Nakayama, Osaka, JP;
Yoshitaka Sugawara, Osaka, JP;
Katsunori Asano, Osaka, JP;
Hidekazu Tsuchida, Yokosuka, JP;
Isaho Kamata, Yokosuka, JP;
Toshiyuki Miyanagi, Yokosuka, JP;
Tomonori Nakamura, Yokosuka, JP;
Koji Nakayama, Osaka, JP;
Yoshitaka Sugawara, Osaka, JP;
Katsunori Asano, Osaka, JP;
Hidekazu Tsuchida, Yokosuka, JP;
Isaho Kamata, Yokosuka, JP;
Toshiyuki Miyanagi, Yokosuka, JP;
Tomonori Nakamura, Yokosuka, JP;
The Kansai Electric Power Co., Inc., Osaka, JP;
Central Research Institute of Electric Power Industry, Tokyo, JP;
Abstract
With a view to preventing increases in forward voltage due to a change with the lapse of time of a bipolar semiconductor device using a silicon carbide semiconductor, a buffer layer, a drift layer and other p-type and n-type semiconductor layers are formed on a growth surface, which is given by a surface of a crystal of a silicon carbide semiconductor having an off-angle θ of 8 degrees from a (000-1) carbon surface of the crystal, at a film growth rate having a film-thickness increasing rate per hour h of 10 μm/h, which is three times or more higher than conventional counterparts. The flow rate of silane and propane material gases and dopant gases is largely increased to enhance the film growth rate.