Finisar Corporation

Roman Dimitrov

Ashish K Verma

David Bruce Young

Tsurugi Sudo

Yuk Lung Ha

Scott Lehmann

Daniel Francis

Sumesh Mani K Thiyagarajan

Richard P Ratowsky

Rashit Nabiev

Sunil Thomas

A method for depositing protective coatings on front and rear facets of an optical device, such as a laser die, is disclosed. The protective coatings help prevent laser facet damage common to laser dies manufactured using known processes. In one embodiment, the method for coating the laser die includes placing the laser in an evacuated coating chamber before applying a first coating portion to a first facet of the laser. The first coating portion is applied to the first facet so as to form a protective covering thereon, but is applied at a coating energy that minimizes damage to the as-yet uncoated second facet. The laser is then rotated within the coating chamber, and a full coating is applied to a second facet of the laser. The laser is again rotated, and a full coating is applied atop the first coating portion to the first facet of the laser.

Method for applying protective laser facet coatings

In one example, an optoelectronic transducer includes a first contact, a second contact, a passivation layer, and a protection layer. The passivation layer is formed on top of the first contact and the second contact and is configured to substantially minimize dark current in the optoelectronic transducer. The protection layer is formed on top of the passivation layer and substantially covers the passivation layer. The protection layer is configured to protect the passivation layer from external factors and prevent degradation of the passivation layer.

Passivated optical detectors with full protection layer

Optimizing the regrowth over epitaxial layers during manufacture of a distributed feedback laser. In one example embodiment, a method for depositing an InP regrowth layer on an epitaxial base portion of a distributed feedback laser includes growing a first portion of the regrowth layer at an initial substrate temperature of approximately 580 degrees Celsius to a thickness between approximately 300 Angstroms and approximately 900 Angstroms, increasing the substrate temperature from the initial substrate temperature to an increased substrate temperature of approximately 660 degrees Celsius, growing a second portion of the regrowth layer at the increased substrate temperature, doping a first part of an uppermost layer of the regrowth layer at a concentration of approximately 8.00*10^17/cm3 at the increased substrate temperature, and doping a second part of the uppermost layer of the regrowth layer at a concentration between approximately 1.90*10^18/cm3 and approximately 2.00*10^18/cm3 at the increased substrate temperature.

Epitaxial regrowth in a distributed feedback laser

In one example, an optical detector includes a photosensitive layer, and a group of additional layers associated with that photosensitive layer. The group of additional layers may include first and second contact layer configured for electrical communication with the photosensitive layer. In this example, one of the group of layers is shaped so as to define a corner whose radius of curvature is greater than about 2 microns.

Photodiode having rounded edges for high electrostatic discharge threshold

A method for etching facets of a laser die prior to coating in such a way as to control the formation of oxides and metallic films on the facet is disclosed. In one embodiment, the method includes placing a wafer on which the laser is included in the interior volume of an etching chamber. Nitrogen is introduced into the interior volume to define a nitrogen-rich environment. The laser facet is then etched in the nitrogen-rich environment with argon delivered from an ion gun. In another embodiment, the method includes placing the laser in an ion beam etching chamber, then physically etching the facet of the laser with an ion beam that includes an argon/nitrogen mixture. The laser facet(s) can then be coated as desired. The etching method reduces the incidence of leakage current during operation of the laser die caused by metallic film formation on the facet before coating.

Laser facet pre-coating etch for controlling leakage current

Embodiments disclosed herein relate to high-speed lasers such as FP and DFB lasers. In one embodiment, the high speed laser comprises a substrate, an active region positioned above the substrate, a mesa positioned above the active region, and one or more layers disposed between the active region and the mesa, wherein the thickness of at least one of the one or more layers is implemented to at least partially minimize the distance between the mesa and active region such that lateral current spreading between the mesa and the active region is at least partially minimized.

Thin INP spacer layer in a high speed laser for reduced lateral current spreading

This disclosure is concerned with starved source diffusion methods for forming avalanche photodiodes are provided for controlling an edge effect. In one example, a method for manufacturing an avalanche photodiode includes forming an absorber layer and an avalanche layer over a substrate. Next, a patterned mask defining one or more openings is formed over a surface of the avalanche layer. Finally, a dopant is deposited over the patterned mask and the avalanche layer such that the dopant is blocked by the patterned mask but diffuses into the avalanche layer in areas where the patterned mask defines an opening. The patterned mask is configured such that the depth to which the dopant diffuses into the avalanche layer varies so as to form a sloped diffusion front in the avalanche layer.

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San Jose, CA, United States of America

Roman Dimitrov