Patent attributes
A technique that makes it possible to enhance the reliability of a module using PCB as its module substrate is provided. Solder connection of a single-chip component 43, an integrated chip component 44, and a semiconductor chip IC2 by Pb-free solder is carried out by heat treatment at a temperature below 280° C. using a heat block. Solder connection of a semiconductor chip IC1 by high-melting point solder is carried out by heat treatment at a temperature of 280° C. or higher using a hot jet. Thus, the semiconductor chip IC1 can be solder connected to PCB 38 using high-melting point solder without the following troubles: damage to the PCB 38 due to heat, for example, burning of solder resist; and peeling of prepreg from a core material. Therefore, the semiconductor chip IC1 can be mounted over the PCB 38 with high connection strength.
