METHOD FOR VACUUM SOLDERING SOLDER BALLS TO LEADING PLATFORMS OF CERAMIC METAL CASES OF MATRIX TYPE Russian patent published in 2024 - IPC B23K1/08 H05K3/34 

FIELD: soldering.

SUBSTANCE: invention relates to the technology of vacuum soldering of electronic equipment and is intended for mounting solder balls on the lead pads of matrix-type metal-ceramic housings. Before applying solder paste, the lead pads of the metal-ceramic body are treated using low-temperature gas-discharge plasma. Solder balls are melted in a vacuum oven. The furnace chamber is evacuated and then filled with nitrogen, then the metal-ceramic body is preheated in the chamber with formic acid vapour supplied to it. After stabilizing exposure, the solder balls are heated to the melting temperature. Vacuum is created in the chamber to remove gases from the solder joint and fill the resulting voids with solder. The chamber is filled with nitrogen to the ambient pressure and cooled.

EFFECT: invention allows soldering without the use of flux on the surface of solder balls with complete filling of the dump pads of the microcircuit with solder paste, and minimizes the growth of oxide films on the surface of calibrated solder balls.

2 cl, 6 dwg