Conductor Layer Design for Heat Dissipation and Crack Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge is to enhance the heat dissipation effect of a conductor layer in semiconductor devices while preventing substrate cracking at the interface between the insulating and conductor layers, which occurs due to differences in linear expansion coefficients during temperature cycling.
Innovation Solution
The solution involves a conductor layer with a heat dissipating conductor layer and a circuit layer separated by an intervening metal layer, where the metal layer is a sintered body with varying porosity and a specific porosity ratio, and the heat dissipating conductor layer is designed with a chamfered edge and a thermal conductivity range of 90 to 427 W/(m·K), along with a coefficient of linear expansion of 3 to 18 × 10^-6/K.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If the area and thickness of the conductor layer are increased to improve heat dissipation, then the heat dissipating effect is improved, but the substrate may crack along the interface between the insulating layer and the conductor layer due to large difference in coefficients of linear expansion
Solution Approach 1:
The conductor layer is designed with non-uniform thickness, being thicker at the heat generating element side and thinner at the circuit layer side. This local variation in thickness allows the conductor layer to have higher heat capacity where needed while reducing the overall difference in linear expansion coefficients with the insulating layer, thereby preventing substrate cracking during temperature cycling
Solution Approach 2:
The invention changes the thickness parameter of the conductor layer from uniform to non-uniform, creating a gradient structure. The thickness transitions from a first thickness at the heat generating element side to a second thickness at the circuit layer side, where the first thickness is greater than the second thickness. This parameter change optimizes both heat dissipation and cracking resistance
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 effectively improves heat dissipation while suppressing substrate cracking, maintaining thermal conductivity and reliability, and ensuring the longevity of the joining interface.
Implementation Method 1
the intervening metal layer is a sintered body of metal particles and the intervening metal layer has a layer inner portion that is in contact with a face of the heat dissipating conductor layer
Implementation Method 2
when a temperature cycle in which the device is placed in a low temperature environment and thereafter in a high temperature environment is repeated, the substrate may crack along an interface between an insulating layer and the conductor layer due to a large difference between a coefficient of linear expansion of the insulating layer adjacent to the conductor layer and a coefficient of linear expansion of the conductor layer
Data Source
Figure 1
Figure 2
Figure 3
AI summary
To improve the heat dissipating effect of a conductor layer while suppressing a crack of a substrate along an interface between an insulating layer and a conductor layer. An electronic circuit device (100) has an insulating layer (10), a conductor layer (2) provided on at least one face side of the insulating layer (10), and a heat generating element (4) provided on a face of the conductor layer (2) at a side opposite of the insulating layer (10) via a joining layer (3). The conductor layer (2) has a heat dissipating conductor layer (21) located on a heat generating element (4) side and a circuit layer (22) located on an insulating layer (10) side, and the shortest distance (l1) between a side end portion of the heat generating element (4) and a side end portion of the heat dissipating conductor layer (21) on a face of the heat dissipating conductor layer (21) on the circuit layer (22) side is greater than or equal to a thickness (t1) of the heat dissipating conductor layer (21).