Heat sink and mfg. method thereof

A radiation device consists of radiation seat made of copper plate and radiation fin which is formed by plurality of thin copper sheets arranged in parallel and in vertical to the radiation seat as they are connected into one body by soldering. The febrication steps of it are as follows: to make the copper plate and copper sheet into a presetting shape of radiation seat or radiation fin by punching press separately first and then to carry on the polishing process for the surface of radiation seat, to place the radiation seat and fin in the protective gas to carry on cheaning process to removethe oil dirt on the surface and to carry on ageing process, to coat the silver. Solder paster in between the radiation seat and fin and to place them in the furnace for silver soldering treatment, tomake antioxidation treatment of copper in radiation seat and fin after they are out of the furnace.