| abstract |
(57) [Abstract] [Purpose] Fine pitch printing pattern for soldering electric elements, extension of life of solder flux, reduction of reflow temperature, reuse of reducing gas during reflow, omission of cleaning after reflow or Make it simple. [Structure] In a method of reflowing a cream solder in a reducing gas atmosphere, the reflow is performed in a container 1 which mainly contains hydrogen gas and has a reducing gas atmosphere independent from the outside inside. |