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:
Nov. 29, 1994
Filed:
Nov. 10, 1993
Abstract
An avalanche photodiode in which a strained superlattice structure is used as a multiplication layer, comprising: an n.sup.+ type InP substrate; an n.sup.+ type InP epitaxial layer formed on a main surface of the substrate; an N type In.sub.1-x Al.sub.x As layer formed on the epitaxial layer; an n.sup.+ type In.sub.1-x Al.sub.x As layer formed on the N type In.sub.1-x Al.sub.x As layer, the n.sup.+ type In.sub.1-x Al.sub.x As layer having a relatively high impurity concentration more than the N type In.sub.1-x Al.sub.x As layer; the multiplication layer deposited on the n.sup.+ type In.sub.1-x Al.sub.x As layer, the multiplication layer having an In.sub.0.53 Ga.sub.0.47 As/In.sub.1-x Al.sub.x As superlattice structure; first and second p.sup.+ type In.sub.1-x Al.sub.x As layers laminated sequentially on the multiplication layer; an absorbing layer formed on the second p.sup.+ type In.sub.1-x Al.sub.x As layer, the absorbing layer being made of an In.sub.0.53 Ga.sub.0.47 As; a P type InP layer formed on the absorbing layer to reduce a surface leakage current; an In.sub.0.53 Ga.sub.0.47 As layer formed on the P type InP layer to be provided for an ohmic contact, and metal layers formed on an upper surface of the In.sub.0.53 Ga.sub.0.47 As layer and the other surface of the substrate, respectively.