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:
Jul. 28, 2009
Filed:
May. 15, 2007
Tsurugi Sudo, San Jose, CA (US);
Ashish Verma, San Jose, CA (US);
Jing Chai, Fremont, CA (US);
Sumesh Mani K. Thiyagarajan, Fremont, CA (US);
Tsurugi Sudo, San Jose, CA (US);
Ashish Verma, San Jose, CA (US);
Jing Chai, Fremont, CA (US);
Sumesh Mani K. Thiyagarajan, Fremont, CA (US);
Finisar Corporation, Sunnyvale, CA (US);
Abstract
A laser diode having a composite passivation layer configured to control parasitic capacitance, especially in high speed laser applications, is disclosed. In one embodiment, a ridge waveguide laser is disclosed and includes: a substrate, an active layer disposed on the substrate, a ridge structure disposed on the active layer, and a contact layer disposed on the ridge structure. A composite passivation layer is disposed substantially laterally to the ridge structure. The composite passivation layer includes a silicon nitride bottom layer, a silicon nitride top layer, and a silicon dioxide middle layer interposed between the bottom and top layers. The passivation layers possess differing stress components that, when combined, cancel out the overall mechanical stress of the passivation layer. This enables relatively thick passivation layers to be employed in high speed laser diodes without increasing the risk of layer stress cracking and laser damage.