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. 28, 2002
Filed:
Feb. 08, 1999
Ryozo Furukawa, Tokyo, JP;
Masanobu Kato, Tokyo, JP;
Abstract
Light on the longer wavelength side can be photoelectrically converted and output reliably, whilst improving the structural and operational reliability of a photodetector, by means of a simple manufacturing process and inexpensive manufacturing costs. A first light-absorbing layer, a buffer layer of a second conductivity type, a second light-absorbing layer of a second conductivity type and a window layer of a second conductivity type are laminated in this order onto the first principal surface of a substrate of a first conductivity type. The first light-absorbing layer contains a region of the first conductivity type and a region of the second conductivity type, and a diffused region of the first conductivity type having a depth extending from the upper face of the window layer to the interface between the window layer and the second light-absorbing layer is provided in a portion of the window layer. A main electrode of a first conductivity type is provided on the diffused region, whilst a main electrode of a second conductivity type is provided on the window layer in the vicinity of the diffused region. The energy gap wavelength of the second light-absorbing layer is longer than the energy gap wavelength of the first light-absorbing layer, whilst the energy gap wavelength of the first light-absorbing layer is longer than the respective energy gap wavelengths of the substrate, buffer layer and window layer.