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:
May. 02, 2000
Filed:
Sep. 25, 1997
Hiroaki Yoshida, Yokohama, JP;
Masayuki Ishikawa, Yokohama, JP;
Hidetoshi Fujimoto, Kawasaki, JP;
Yoshihiro Kokubun, Yokohama, JP;
Genichi Hatakoshi, Yokohama, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
In the semiconductor light emitting device, a high resistance layer formed by mutual diffusion at an interface with the substrate crystal can be eliminated, and a low resistance p-type contact can be realized. In addition, it is possible to reduce the leak current when an internal current-blocking structure is formed. In practice, a compound semiconductor layer offset in composition ratio stoichiometrically is used as the contact layer. Further, when a predetermined element is added to the contact layer, a large amount of doping can be enabled in comparison with when impurities are added to the ordinary GaN based layer. Therefore, a high concentration conductive type layer can be realized while reducing the contact resistance. In addition, when the compound semiconductor layer offset away from the stoichiometric composition is used as the current-blocking layer, the current-blocking efficiency can be improved. Further, when the substrate is irradiated with light having energy slightly higher than that of the band gap of the grown crystal in the photo-excitation MOCVD method in order to eliminate the rough surface, it is possible to realize the p-type conductive of high carrier concentration.