To achieve a jointing part excellent in thermal resistance and thermal fatigue, and face-jointing a wiring conductor to a surface electrode of a semiconductor device and jointing the semiconductor device to a conductor substrate with high positional precision, using a soldering material free from lead.

A solder paste of a Sn3.5Ag0.5Cu particle (melting temperature: 220°C) is applied on the surface of a conductor substrate 12; and a semiconductor device 14 is placed thereon. A cream solder of mixed particles (solidus temperature: 220°C, liquidus temperature: 345°C) of a Sn20Ag20Cu0.4Ni powder and a Sn3.5Ag0.5Cu0.07Ni0.01Ge powder in the weight ratio of 62:35, is applied on a surface electrode of the semiconductor device 14; and a wiring conductor 16 is placed thereon. The resultant is heated at 250°C in this state to melt the solder paste of the Sn3.5Ag0.5Cu particle and to make the cream solder of a Sn14.2Ag13.2Cu0.28Ni0.035Ge in total composition into a solid-liquid coexistence state. Then, the resultant is cooled to joint the conductor substrate 12, the semiconductor device 14 and the wiring conductor 16 through the Sn3.5Ag0.5Cu jointing material 17 and the Sn14.2Ag13.2Cu0.28Ni0.035Ge jointing material 15.

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