Laser Welding and Packaging Technology of Three-dimensional Direct Plated Copper Ceramic Substrate
Hermetic sealing is a crucial packaging method that promotes the high reliability development of elec-tronic devices.Traditional hermetic packaging technologies have some problems,such as high welding temperatures and thermal shock and limited application ranges,which cannot meet requirements for hermetic packaging of three-dimensional direct plated copper ceramic substrate(3-D DPC).In this study,combining with the technical advan-tages of pulsed laser welding,we investigated the achievement of hermetic packaging of 3-D DPC using pulsed laser welding.The interaction mode between pulsed laser and materials during the welding process was discussed,and the interface microstructure,hermeticity,and mechanical properties of the welding samples were analyzed.The re-search indicates that the formation of cracks in welded metal area is closely related to the diffusion of copper from the base metal to the Kovar side.The heat conduction mode and transition mode with stable welding process and low depth of fusion can avoid the formation of welding cracks.The welding process parameters were optimized through ex-periments.At a peak laser power of 120 W,a pulse width of 1 ms,and an overlap rate of 80%,the three-dimension-al ceramic substrate cavity packaging structure achieved the optimal high hermeticity,with a leakage rate of 5.2×10-10 Pa·m3/s and a joint shear strength of 278.06 MPa,meeting the requirements for high-reliability hermetic pack-aging of third-generation semiconductor devices.
pulsed laserwelding modehermetic packagingthree-dimensional direct plated copper ceramic sub-strate(3-D DPC)
国家科技期刊平台
NSTL
万方数据
