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:
Aug. 13, 2002
Filed:
Mar. 29, 2001
Hiroyuki Hosoba, Souraku-gun, JP;
Hiroshi Nakatsu, Tenri, JP;
Takahisa Kurahashi, Kashiba, JP;
Tetsurou Murakami, Tenri, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
On an n-GaP substrate transparent against a radiation light of an InAlGaP based semiconductor element, a lattice distortion relaxation layer, a clad layer , an active layer, and a clad layer are created with InAlGaP. On top of the layers, there is formed an In Ga P current diffusion layer with In composition ratio x equal to (0<X<1). Through these steps, uneven depth on the crystal surface is decreased and crystal defect concentration is lowered. In addition, the energy gap of the current diffusion layer is made larger than the energy gap of the active layer, so that the GaP substrate and the uppermost InGaP current diffusion layer become transparent against a radiation light from the active layer, resulting in increased light emitting efficiency. Further, simple formation of layers from the lattice distortion relaxation layer to the current diffusion layer in sequence enables reduction of the production costs.