Patent attributes
When a distance between an end portion of a brazing material and a downward extended line of a side surface of an insulating substrate is taken as “a”, and a distance between an end portion of a solder resist on the side of a solder and the downward extended line of the side surface of the insulating substrate is taken as “b”, the positional relationship a<b is satisfied. The position of the end portion of the solder is regulated by the solder resist, and the position of the end portion of the brazing material on the side of the side surface of the insulating substrate is closer to the side of the side surface of the insulating substrate than to the position of the end portion of the solder on the side of the side surface of the insulating substrate.
