Conductive SiC Substrate for Semiconductor Laser Heat Dissipation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional semiconductor laser devices using monocrystalline silicon carbide (SiC) sub-mounts with insulating properties face challenges in heat dissipation due to the presence of micropipes, which complicate the filling process and impede thermal conduction, and can lead to electrical leakage and short-circuits.
Innovation Solution
A semiconductor laser device employing a monocrystalline SiC substrate with electrical conductivity, which contains fewer micropipes, is used as a sub-mount, along with an insulating film to prevent electrical leakage and short-circuits, simplifying the fabrication process and enhancing heat dissipation by eliminating the need to seal micropipes with insulating material.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a monocrystalline SiC substrate with insulating properties is used as a sub-mount, then electrical insulation is improved, but heat dissipation deteriorates due to micropipes impeding thermal conduction
Solution Approach 1:
The invention changes the electrical conductivity parameter of the SiC substrate from insulating to conductive by controlling impurity concentration (≥1×10^14/cm³). This parameter change simultaneously improves heat dissipation while maintaining electrical insulation through the conductive substrate's inherent properties
Solution Approach 2:
The invention converts the previously harmful micropipes (which impeded thermal conduction in insulating substrates) into a non-issue by using a conductive SiC substrate where micropipes do not significantly affect thermal performance, thereby turning a defect into a manageable characteristic
2Reliability
If micropipes in insulating SiC substrates are filled with insulating material to prevent electrical leakage, then electrical insulation is improved, but manufacturing complexity increases
Solution Approach 1:
The invention extracts and eliminates the problematic step of filling micropipes with insulating material by using a conductive SiC substrate instead. The conductive substrate inherently manages electrical insulation differently, removing the need for this complex fabrication step
Solution Approach 2:
Instead of using an insulating substrate and adding insulating material to fill defects, the invention inverts the approach by using a conductive substrate where the conductivity itself is managed through impurity control, reversing the conventional wisdom of using insulating materials for electrical isolation
3Reliability
If a monocrystalline SiC substrate with insulating properties is used, then electrical insulation is improved, but thermal conduction deteriorates
Solution Approach 1:
The invention changes the electrical conductivity parameter of the SiC substrate from insulating to conductive by controlling impurity concentration (≥1×10^14/cm³). This parameter change simultaneously improves heat dissipation while maintaining electrical insulation through the conductive substrate's inherent properties
Solution Approach 2:
The invention uses a composite structure combining conductive SiC substrate with an insulating film layer to achieve both thermal conduction (through the conductive substrate) and electrical insulation (through the insulating film), creating a functional composite material system
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 semiconductor laser device achieves improved heat dissipation and insulating properties, reducing the complexity of the fabrication process and minimizing the risk of electrical failures, while maintaining high thermal conductivity and stability.
Implementation Method 1
a large number of micropipes existing inside the substrate may lead to an adverse factor that impedes the thermal conduction of the substrate
Implementation Method 2
it employs a monocrystalline SiC of an insulating property having a resistance to the extent to prevent the leakage of those components
Data Source
AI summary
Disclosed herein is a semiconductor laser device utilizing a monocrystalline SiC substrate that is capable of assuring a sufficient heat dissipation property. The semiconductor laser device comprises: a monocrystalline SiC substrate having an electrical conductivity, the substrate having a first surface and a second surface; and a semiconductor laser chip (LD chip) arranged on the first surface. Also, the semiconductor laser device may comprise an insulating film arranged at a side of the first surface of the SiC substrate and configured to insulate a first electric conductive layer onto which the semiconductor laser chip is mounted and an electric conductive member (a second electric conductive layer and a heatsink portion) to be joined to a side of the second surface of the SiC substrate.