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. 23, 1998
Filed:
Aug. 30, 1996
Yasushi Fujioka, Nara, JP;
Shotaro Okabe, Nara, JP;
Masahiro Kanai, Soraku-gun, JP;
Akira Sakai, Soraku-gun, JP;
Yuzo Koda, Tsuzuki-gun, JP;
Tadashi Hori, Nara, JP;
Tomonori Nishimoto, Tsuzuki-gun, JP;
Takahiro Yajima, Soraku-gun, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A photovoltaic device comprises a semiconductor region having at least one set of semiconductor layers comprised of a first semiconductor layer having a first conductivity type, an intrinsic or substantially intrinsic second semiconductor layer, and a third semiconductor layer having a conductivity type opposite to that of the first conductivity type, the layers being formed in this order, and first and second electrodes provided such that the electrodes interpose the semiconductor region; wherein the density of a dopant impurity determining the conductivity type of the first semiconductor layer in a set of semiconductor layers which is in contact with the first electrode is varied so as to be lower on the side of the first electrode, or the grain size of crystals in the first semiconductor layer is varied so as to be smaller on the side of the first electrode. This provides a photovoltaic device that does not exhibit great lowering of characteristics even when short circuits locally occur in the semiconductor layers during long-term service.