Method for producing a printed circuit board with a heat radiating structure and a printed circuit board with a heat radiating structure

A method for producing a printed circuit board (100) with at least one heat radiating structure, comprising the steps of:

• preparing a printed circuit board (100) having conductor patterns (13) and lands (16;
• 17) made of conductive foil formed on first and second surfaces (12a;
• 12b) of an insulating substrate (12), at least one soldering land (22) for heat radiation on the first surface (12a) to define a mounting surface for an electronic part (20) and at least one land (25) for solder absorption on the second surface (12b), at least one viahole (24) with opposite first and second openings (24a, 24b) respectively in the soldering land (22) for heat radiation and the land (25) for solder absorption;
• placing a first metal mask (35) on the first surface;
• applying a cream solder (36) to the lands (16;
• 17) and the soldering land (22) for heat radiation;
• placing the electronic part (20) on the first surface;
• melting the first solder (36) in a first reflow process to solder-connect lead terminals (20b;
• 20c) of the electronic part (20) to the lands (16;
• 17) and to cause the molten solder to flow through the viahole (24) and onto the land (25) for solder absorption adjacent the second openings (24b);
• placing a second metal mask (40) on the second surface (12b);
• applying s second solder (41) to the land (25) for solder absorption to at least partly cover portions of the first cream solder (36) solidified adjacent the second opening (24b) of the viahole (24);
• and
• melting the second solder (41) in a second reflow process to form a solder layer on the land (25) for solder absorption.