IP Library Granted Patent US 7,920,613
Granted Patent B2
US 7,920,613 · App. 12/245,780 · Granted Apr 5, 2011

Optical semiconductor device and method of manufacturing same

View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 7,920,613
App. No.
12/245,780
Granted
Apr 5, 2011
Kind
B2
Abstract

The reliability of a buried hetero-structure semiconductor laser is improved by preventing an increase in oscillation threshold current and a decrease in external differential quantum efficiency in cases where the semiconductor laser is energized continuously under conditions of high temperature and high optical output. An optical semiconductor laser has an optical waveguide structure comprising an n-type cladding layer, an active layer and p-type cladding layers, and a current narrowing/blocking structure comprising a p-type blocking layer and an n-type blocking layer, wherein concentration of hydrogen contained in the p-type cladding layers is higher than concentration of hydrogen contained in the p-type blocking layer.

Claims (6)

1. An optical semiconductor device comprising:

an optical waveguide structure comprising an n-type cladding layer, an active layer and a p-type cladding layer; and

a current narrowing/blocking structure comprising a p-type blocking layer and an n-type blocking layer;

wherein said p-type cladding layer has a higher concentration of hydrogen than the concentration of hydrogen contained in said p-type blocking layer.

2. The device according to claim 1 , wherein the concentration of hydrogen contained in said p-type cladding layer is two or more times greater than the concentration of hydrogen contained in said p-type blocking layer.

3. The device according to claim 1 , wherein said n-type cladding layer and said n-type blocking layer are n-type InP, and said p-type cladding layer and said p-type blocking layer are p-type InP.

Assignments (3)
CHANGE OF ADDRESS Recorded Nov 29, 2017
From: RENESAS ELECTRONICS CORPORATION
To: RENESAS ELECTRONICS CORPORATION
Reel/Frame 044928/0001 →
CHANGE OF NAME Recorded Oct 28, 2010
From: NEC ELECTRONICS CORPORATION
To: RENESAS ELECTRONICS CORPORATION
Reel/Frame 025214/0687 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 6, 2008
From: SAKATA, YASUTAKA
To: NEC ELECTRONICS CORPORATION
Reel/Frame 021634/0300 →