Abstract
The low-pressure cold spray (LPCS) technique could be an attractive method for copper metallization of ceramic substrates to power module applications due to its one-step quick and low-temperature process. However, manufacturing pure copper coating on a ceramic substrate by LPCS is still challenging due to its low deposition efficiency and poor adhesion strength. Our previous study successfully demonstrated the possibility of obtaining a zirconia substrate's metallization by using a feedstock powder mixture of copper and aluminum. However, the copper content in the coating was not high enough for power module applications. Therefore, in this study, we aim to improve the copper content in the coating layer composed of the composite powder deposited by LPCS on alumina and zirconia substrates. The influence of the gas pressure and standoff distance on the copper content and coating thickness are evaluated. The coating build-up with a high copper content and thickness is highly dependent on the kinetic energy of particles, enhanced by high gas pressure and short stand-off distance.