| 摘要 |
<p>PURPOSE:To fuse a necessary solder without damaging a circuit substrate when a surface mounting component is soldered by providing a pattern having a high reflectivity to a laser beam in a laser beam irradiating range. CONSTITUTION:A pattern 2 having a size equal to or larger than a laser beam irradiating range and a high reflectivity to the laser beam is provided on the lower layer of a surface layer 3 oppositely to a pad for placing the surface mounting component. If a laser beam 4 is radiated to its irradiating range 6, when a pad 1 for placing the component is radiated, the laser beam 4 is absorbed to the paste-like solder coating the pad 1 together with the pad 1 and the terminal of the component to generate heat, thereby fusion-bonding the solder to the pad 1 and the terminal to be electrically connected. when it is irradiated to a surface layer 3 except the pad 1, even if it arrives at the pattern 2 provided on a lower layer of the pad 1 and having high reflectivity to the laser beam, the beam 4 is reflected out of the layer 3 and the circuit substrate but not absorbed. Accordingly, a necessary part is not heated.</p> |
