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:
Feb. 22, 2005
Filed:
Apr. 11, 2003
Hiroaki Kakinuma, Tokyo, JP;
Mikio Mohri, Tokyo, JP;
Hiroaki Kakinuma, Tokyo, JP;
Mikio Mohri, Tokyo, JP;
Oki Electric Industry Co., Ltd., Tokyo, JP;
Abstract
A photodiode () and resistors () are formed on a semi-insulating InP substrate (). The photodiode () is formed by subjecting a layered structure formed by successively depositing an n-type InP cladding layer (), an n-type InGaAsP core layer (), a nondoped InGaAs active layer (), a p-type InGaAsP core layer (), and a p-type InP cladding layeron the InP substrate () to a selective etching process. The resistors () have the same layered structure as the photodiode (). Photodiode () is connected to n-type wiring lines () and a p-type wiring line (). Resistors () are connected to the n-type wiring lines () and the p-type wiring line () in parallel to the photodiode (). A side surface on the side of the photodiode () of the InP substrate () is a cleavage plane, and the cleavage plane is coated with an antireflection film (). Since the resistors () have a p-type semiconductor layer having a high resistivity, the resistors () can be formed in a big width. Consequently, change of resistance corresponding to change of the width of the resistor is small and hence matching can be easily achieved.