Non-Absorbing Laser Mirror Structure for Facet COD Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High-power semiconductor laser diodes face issues with facet/mirror surface stability due to power degradation and catastrophic optical damage (COD).
Innovation Solution
A method involving two growth runs and a selective etching step is used to form a laser device with non-absorbing regions at the ends of active regions, enhancing facet stability without requiring deep etching or selective re-growth.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If deep etching is performed to form non-absorbing regions, then facet stability is improved, but manufacturing complexity and cost increase
Solution Approach 1:
The manufacturing process is divided into two separate growth runs with an etching step in between. The first growth run forms the initial structure, the etching step creates the non-absorbing region by removing material, and the second growth run completes the device. This segmentation allows the etching to be performed on a partially formed structure rather than requiring deep etching through the entire device, thereby reducing manufacturing complexity while achieving the desired facet stability.
Solution Approach 2:
The etching step is performed preliminarily during the first growth run before the second growth run completes the device structure. By performing the etching action at this intermediate stage, the non-absorbing region is formed before the final device structure is complete, avoiding the need for deep etching through the entire device and reducing manufacturing complexity while maintaining facet stability.
2Reliability
If deep etching is performed to form non-absorbing regions, then catastrophic optical damage is reduced, but manufacturing cost increases
Solution Approach 1:
The process is segmented into two growth runs with etching in between, allowing the etching step to work on a partially formed structure. This reduces the depth and complexity of the etching required compared to forming non-absorbing regions in a fully grown device, thereby reducing manufacturing cost while still achieving protection against catastrophic optical damage.
Solution Approach 2:
The etching step is performed preliminarily before the second growth run completes the device. This timing allows the etching to be performed more easily and cheaply on a less complex structure, reducing manufacturing cost while still achieving the desired protection against catastrophic optical damage through the formation of non-absorbing regions.
3Ease of manufacture
If conventional single growth run is used, then manufacturing is simpler, but power degradation occurs
Solution Approach 1:
The manufacturing process is segmented into two growth runs with an etching step, which adds some complexity but enables the formation of non-absorbing regions that prevent power degradation. The segmentation allows for precise control of the device structure and material properties, achieving power degradation resistance while keeping the added manufacturing complexity minimal.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The method effectively stabilizes the facets of high-power laser diodes, reducing the risk of catastrophic optical damage and power degradation, while avoiding the complexities and costs associated with deep etching.
Implementation Method 1
performing a first growth run, including epitaxially growing first, second, and third preform layers on a substrate
Implementation Method 2
removing parts of the second and third preform layers by etching the second and third preform layers to form one or more etched regions
Data Source
AI summary
A laser device with one or more active regions, such as quantum wells, gain/lighting media, or other devices, and one or more non-absorbing regions, may be formed by a first growth run (growing a first semiconductor layer), then performing selective, shallow-depth etching, and then a second growth run (growing a second semiconductor layer). The laser device may include a first portion, one or more active regions located on the first portion, and a second portion located on the active region(s). A third portion may be located on one or more ends of the first portion and on the second portion. The third portion may be formed during the second growth run, after the etching step. The non-absorbing region(s) may be formed by the third portion and the end(s) of the first portion. If desired, the non-absorbing region(s) may be produced without annealing or locally-induced quantum well intermixing.