Metal Injected Copper Carbon Nanotube Composite Material with High Thermal Conductivity and Low CTE for IGBT Power Modules

Abstract

Power modules, particularly in hybrid and electric vehicles, have become an essential part of their thermal management system design. In power cooling modules, the temperature variations are important issues, leading to thermal stresses caused by different coefficients of thermal expansion (CTE) in the composite materials. Thus, one should consider suitable materials and manufacturing processes to achieve the best performance and reliability during the device's life cycle. The Cu/CNT-Cu material is assumed to have a unique combination of a high thermal conductivity and low coefficient of thermal expansion, which results in a new composite material that goes beyond the ability of regular materials. To address this, we have developed the Cu/CNT-Cu composite with a significant improvement in thermal conductivity (³327 W/mK) which is within the industrial scale range of copper metal injection molding (320340 W/mK) and low coefficient of thermal expansion (³6 ppm/K), both of which make it an excellent choice for power modules in next generation automobiles. This was achieved by reducing the voids and increasing the interface bonding while adding the copper coated CNTs, which were made by an electroplating process. This mixed Cu/CNT-Cu property makes it the top material design selection in the Ashby map and has a better temperature stability due to its lower thermal distortion parameter (TDP). As a result, this material will represent a significant scientific and technological development in the advancement cooling of IGBT power module devices.

Copper Like Thermal Conductivity and Silicon Like Coefficient of Thermal Expansion Copper Graphene for High Power IGBT by Metal Injection Molding

“…Thus, several factors such as metal powder shape, the suitable parameters of metal injection molding, debinding and sintering processes got the huge effect on the outcomes. 3) Base on the experimental result in the Fig. 6(a), the lowest porosity occurs in Exp.2 of 0.2% Graphene and therefore it will cause the highest density Fig.…”

“…38) (b) IGBT power module schematic illustrating the chip, DCB substrate, and pin-fin heat sink. 3) further degrade heat removal efficiency. 6) As a result, it is necessary to choose as similar CTE and thermal conductivity as possible for materials used in IGBT.…”

Structural Design and Fabrication of Multifunctional Nanocarbon Materials for Extreme Environmental Applications

“…a) Ashby map of thermal conductivity versus TDP of ceramics, [ 25c,53 ] metals, [ 25c,32b ] polymer materials, [ 32b ] nanocarbon materials, [ 54 ] and their composites. [ 25c,54b,55 ] b) Ashby map of operating temperature limitation versus normalized thermal conductivity of ceramics, [ 15b–d,31b,56 ] metals, [ 25c,57 ] polymer materials, [ 38f,58 ] nanocarbon materials, [ 28b,29,48a,59 ] and their composites. [ 60 ]…”

“…mixed polyimide (PI) with randomly dispersed graphene oxide (GO) nanosheets (20 wt%) and reported a TDP of 35 ppm m W −1 , only 1/10 of raw polymers, with a thermal conductivity of 0.81 W m −1 K −1 . [ 55b ] It was interpreted that the low‐dimensional and rigid GO nanosheets were able to enhance chain orientation of PI, thereby suppressing the thermal expansion of the PI matrix.…”