Spacer-Bonded Ceramic Power Module for Stable Chip Clearance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Power modules used in hybrid and electric vehicles face challenges in achieving high strength, efficient heat dissipation, and reliable bonding while minimizing volume and electrical losses, especially due to the high voltage and vibration generated by silicon carbide (SiC) or gallium nitride (GaN) semiconductor chips.
Innovation Solution
A power module design featuring a duplex structure of ceramic substrates with spacers, where insulating or conductive spacers maintain a constant interval between the substrates, enhancing heat dissipation and bonding reliability through brazing or soldering processes, and using Ag paste for improved thermal conductivity and bonding strength.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If a power semiconductor chip is mounted between two substrates to achieve high voltage and current output, then the power module can drive motors in hybrid and electric vehicles, but high heat is generated during driving
Solution Approach 1:
The cooling function is segmented into two independent heat sinks positioned on opposite sides of the substrate, allowing heat to be dissipated from both the upper and lower surfaces of the power semiconductor chip simultaneously, rather than relying on a single cooling path
Solution Approach 2:
The heat dissipation approach transitions from one-dimensional (single-sided cooling) to three-dimensional (double-sided cooling with heat sinks on both upper and lower sides), creating multiple thermal pathways for heat removal
2Temperature
If the interval between ceramic substrates is not constantly maintained, then the structure may be simpler, but the semiconductor chip is not protected and heat dissipation efficiency is reduced
Solution Approach 1:
A spacer is introduced as an intermediary component between the upper and lower ceramic substrates to maintain a constant interval, protecting the semiconductor chip and ensuring optimal heat dissipation without requiring complex active control mechanisms
Solution Approach 2:
The spacer is positioned at specific locations between the substrates to maintain the interval where it is most needed for chip protection and heat dissipation, rather than uniformly complicating the entire structure
3Reliability
If bonding is performed directly between substrates without spacers, then the bonding process is simpler, but bonding reliability is reduced and thermal or mechanical impact on substrates increases
Solution Approach 1:
The spacer serves as a mediator during the bonding process, positioning the substrates at the correct interval and distributing bonding forces, which improves bonding reliability while actually simplifying the bonding process by providing a mechanical reference
Solution Approach 2:
The spacer is placed beforehand between the substrates to cushion and distribute the thermal and mechanical impact during bonding, preventing direct stress concentration on the substrates and improving bonding success rate
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 design achieves high strength, efficient heat dissipation, and improved bonding reliability, reducing volume and electrical losses, thereby enhancing the performance and lifespan of the power module by maintaining a consistent interval between ceramic substrates and facilitating rapid heat transfer.
Implementation Method 1
a first bonding layer configured to bond the one end of the spacer to the lower ceramic substrate
Implementation Method 2
bonding the one end of the spacer to the lower ceramic substrate through the medium of the first bonding layer
Implementation Method 3
a second bonding layer configured to bond the other end of the spacer to the upper ceramic substrate
Implementation Method 4
bonding the upper ceramic substrate to the other end of the spacer through the medium of the second bonding layer
Implementation Method 5
using Ag paste for improved thermal conductivity and bonding strength
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
The present invention relates to a power module and a method for manufacturing same, the power module including: a lower ceramic substrate; an upper ceramic substrate which is disposed spaced apart from the upper portion of the lower ceramic substrate, and on the lower surface of which a semiconductor chip is mounted; spacers each having one end bonded to the lower ceramic substrate and the other end bonded to the upper ceramic substrate; first bonding layers each bonding the one end of each spacer to the lower ceramic substrate; and second bonding layers each bonding the other end of each spacer to the upper ceramic substrate. The present invention maintains a constant distance between the lower ceramic substrate and the upper ceramic substrate by having the spacers arranged therebetween, and thus is advantageous in that the semiconductor chip can be protected and heat dissipation efficiency can be increased.