Multi-Emitter Laser Structure With Trenches for Uniform Current Injection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional GaN-based laser diodes in multi-emitter arrays suffer from inadequate device performance due to issues such as filamenting, asymmetric optical field profiles, and non-uniform current injection, which degrade performance as the stripe width increases.
Innovation Solution
The laser device structure includes trenches along the p-contacts that are partially filled with a dielectric material, with a planar surface, and n-contacts separated by isolation trenches, allowing for individually addressable emitters and symmetric optical field profiles, reducing filamenting and improving uniform current distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If multi-emitter arrays are used to increase application range, then output power and application versatility improve, but device performance degrades due to filamenting and non-uniform current injection
Solution Approach 1:
The patent divides the multi-emitter array into individually addressable emitters by introducing trenches between adjacent emitters. These trenches act as isolation structures that segment the current paths, preventing current leakage and non-uniform distribution. Each emitter can be independently controlled through its own contact structure, eliminating the filamenting effect that occurs in conventional multi-emitter arrays.
2Power
If stripe width is increased to improve output power, then power increases, but optical field profile becomes asymmetric and current injection becomes non-uniform
Solution Approach 1:
The patent introduces trenches with specific geometries and dielectric materials at localized positions between emitters to create symmetric current distribution and optical field profiles. The trenches are positioned and dimensioned to locally modify the electrical and optical properties, ensuring that each emitter maintains a symmetric profile even when stripe width is increased for higher power output.
3Ease of manufacture
If conventional multi-emitter structures are used, then manufacturing is simpler, but device performance is inadequate due to filamenting and asymmetric profiles
Solution Approach 1:
The trenches are formed as part of the epitaxial growth process or early fabrication steps, establishing the isolation structures before subsequent processing. This preliminary formation of trenches with dielectric materials pre-defines the current paths and emitter boundaries, simplifying later manufacturing steps while ensuring consistent device performance across the multi-emitter array.
Data Source
AI summary
A laser device structure on a carrier substrate, a bonding material overlying the carrier substrate, an epitaxial region overlying the bonding material, a plurality of p-contacts disposed between a first surface of the epitaxial region and the bonding material, trenches extending on either side of and along longitudinal sides of each p-contact of the plurality of p-contacts, and a plurality of n-contacts disposed on a second surface of the epitaxial material opposite the first surface.