Interface stress analysis and bonding strengthening exploration of metal layer on the laser-activated copper-clad AlN.

Aluminum nitride ceramics has excellent thermal conductivity and insulation property, making it a kind of excellent electronic packaging material. But enhancing the bonding strength between the metal layer and aluminum nitride (AlN) ceramic is a challenging problem. Especially regarding the lack of accurate data analysis on the stress between interfaces, enhancing adhesive strength still relies on blind attempts. By using the finite element method, this study reveals that the shear stress generated between the metal/ceramic interface is concentrated at the interface edge. Based on this finding, a method of inserting micro-pore arrays at the edge is proposed to enhance the interfacial bonding strength. The simulation results show that by inserting micro-pores with an appropriate density, the interface shear stress between metal and ceramic can be reduced obviously by 36 %. Finally, vertical peel-off verification experiments were designed. After inserting micro-pores to the interface, the bonding strength of the interface increased from 8.75 MPa to 11.69 MPa, and the performance was improved by 33.6 %. The experimental results were consist with the simulation results and indicated that the micro-pores had a significant effect on improving the bonding strength. • A method is proposed to insert micropores at the edge of the AlN interface to enhance the interface bonding strength. [ABSTRACT FROM AUTHOR]