Multi-emitter Diode Laser Package with Vertical Sub-mounts
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing diode laser packages face challenges in achieving compact, efficient heat dissipation and optical coupling for high-power applications, particularly in vertically stacked configurations, due to complex cooling carrier designs and long heat dissipation paths.
Innovation Solution
A laser diode assembly with vertically oriented diode chips mounted on a carrier base using sub-mounts on both sides, allowing for efficient heat transfer and optical alignment, where the distance of the active area to the carrier base is optimized to facilitate both heat dissipation and optical coupling, with sub-mounts made of ceramic materials and conductive layers for electrical connection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If multiple laser diode chips are vertically stacked to achieve high power, then power output is improved, but device complexity increases due to complex cooling carrier designs and alignment requirements
Solution Approach 1:
The device is segmented into multiple identical sub-assemblies, each comprising a laser diode chip mounted on a separate sub-mount. This modular segmentation allows each unit to be independently cooled and aligned, reducing the overall system complexity while achieving high power through combination of multiple units.
Solution Approach 2:
The invention transitions from planar mounting to vertical stacking configuration, utilizing the third dimension (height) to arrange multiple laser diode chips. This dimensional change enables compact high-power output while simplifying thermal management through vertical heat dissipation paths to the carrier base.
2Area of stationary object
If laser diode chips are vertically stacked to reduce footprint, then area is reduced, but heat dissipation path length increases
Solution Approach 1:
Each laser diode chip is mounted on its own sub-mount with direct thermal contact to the carrier base, creating segmented thermal pathways. This ensures that heat from each chip travels a short, direct path to the cooling carrier, avoiding long heat dissipation paths even in vertical stacking configuration.
Solution Approach 2:
By stacking chips vertically with direct mounting on the carrier base through sub-mounts, the heat dissipation path is optimized to extend vertically rather than laterally. This dimensional reorientation reduces the horizontal footprint while maintaining efficient vertical heat transfer paths.
3Reliability
If sub-mounts are made conductive for electrical connection, then electrical conductivity is improved, but thermal insulation performance deteriorates
Solution Approach 1:
The sub-mount structure is segmented into distinct functional zones: conductive regions for electrical connection and thermally insulating regions for heat management. This spatial segmentation allows simultaneous optimization of electrical conductivity where needed and thermal insulation where required, resolving the trade-off between these two properties.
Solution Approach 2:
The sub-mount exhibits local quality variation with conductive material or structures positioned specifically for electrical connection reliability, while other portions maintain thermal insulation properties. This localized differentiation allows the same component to satisfy both electrical and thermal requirements in different regions.
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
This configuration enables a compact, high-power diode laser module with improved heat dissipation and optical alignment, reducing thermal lensing effects and complexity, while allowing for precise alignment of emitting areas for enhanced beam quality.
Implementation Method 1
each of the plurality of sub-mounts being a ceramic material that is at least partially covered with a layer of conducting material, each of the plurality of sub-mounts being attached directly or indirectly to the carrier base
Implementation Method 2
each of the plurality of sub-mounts being a ceramic material that is at least partially covered with a layer of conducting material
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
A laser diode assembly contains a plurality of laser diode chips (1402) packaged closely in a row. Each laser diode chip is bonded on both P-side and N-side to first and second sub-mounts (1409,1410). The sub-mounts are then attached to a cooling carrier (1401), with both bonding surfaces perpendicular to the top surface of the carrier. The direction of laser radiation is parallel to the carrier top surface, and the distance between the top (1404) of the active area (1403) of the laser diode chip and the carrier is preferably in a range of half a pitch (1413) between individual laser sources packaged in a row, preferably in a range of 0.2 mm to 1 mm to allow efficient cooling for high power operation. The sub-mounts may be electrically conductive, or they may be of insulating material at least partially covered with a conducting layer.