A method for soldering a surface-mount component onto a circuit board. The melting of die-bonding solder material is prevented by using a mounting solder material when soldering a surface-mount component formed using the die-bonding solder material onto a printed circuit board. The surface-mount component, formed using (SnSb)-based solder material having high melting point, the (SnSb)-based solder material containing Cu but not more than a predetermined quantity of Cu constituent and a main ingredient thereof being Sn, is soldered on a board terminal portion of a circuit board using (SnAgCuBi)-based solder material or (SnAgCuBiIn)-based solder material as the mounting solder material and with the solder material being applied on the terminal portion. Since solidus temperature of the die-bonding solder material is 243 degrees C. and liquidus temperature of the mounting solder material is about 215 through 220 degrees C., the melting of die-bonding solder material is prevented even at the heating temperature (240 degrees C. or less) of a reflow furnace.

A method for soldering a surface-mount component onto a circuit board. The melting of die-bonding solder material is prevented by using a mounting solder material when soldering a surface-mount component formed using the die-bonding solder material onto a printed circuit board. The surface-mount component, formed using (SnSb)-based solder material having high melting point, the (SnSb)-based solder material containing Cu but not more than a predetermined quantity of Cu constituent and a main ingredient thereof being Sn, is soldered on a board terminal portion of a circuit board using (SnAgCuBi)-based solder material or (SnAgCuBiIn)-based solder material as the mounting solder material and with the solder material being applied on the terminal portion. Since solidus temperature of the die-bonding solder material is 243 degrees C. and liquidus temperature of the mounting solder material is about 215 through 220 degrees C., the melting of die-bonding solder material is prevented even at the heating temperature (240 degrees C. or less) of a reflow furnace.

The melting of die-bonding solder material is prevented even when soldering a surface-mount component formed using the die-bonding solder material on a printed circuit board using a mounting solder material. The surface-mount component formed using (SnSb)-based solder material having high melting point as the solder material for die pad, the (SnSb)-based solder material containing Cu not more than a predetermined quantity of Cu constituent and a main ingredient thereof being Sn, is soldered on a board terminal portion of a circuit board using (SnAgCuBi)-based solder material as the mounting solder material with the solder material being applied on the terminal portion. The melting of die-bonding solder material is prevented even at the heating temperature (240 degrees C. or less) of a reflow furnace.

The melting of die-bonding solder material is prevented even when soldering a surface-mount component formed using the die-bonding solder material on a printed circuit board using a mounting solder material. The surface-mount component formed using (SnSb)-based solder material having high melting point as the solder material for die pad, the (SnSb)-based solder material containing Cu not more than a predetermined quantity of Cu constituent and a main ingredient thereof being Sn, is soldered on a board terminal portion of a circuit board using (SnAgCuBi)-based solder material as the mounting solder material with the solder material being applied on the terminal portion. The melting of die-bonding solder material is prevented even at the heating temperature (240 degrees C. or less) of a reflow furnace.

A method and structure for joining a semiconductor device and a laminate substrate or two laminate substrates where the joint is formed with lead free solders and lead free compositions. The various lead free solders and lead free compositions are chosen so that there is a sufficient difference in liquidus temperatures such that some components may be joined to, or removed from, the laminate substrate without disturbing other components on the laminate substrate.

There is provided a palladium-coated copper bonding wire that does not cause a shrinkage cavity during first bonding, has high bonding reliability, and is capable of maintaining excellent bonding reliability for a long period of time even in high-temperature and high-humidity environments. A palladium-coated copper bonding wire in which a concentration of palladium is 1.0 mass % or more and 4.0 mass % or less relative to the total of copper, palladium, and a sulfur group element, a total concentration of the sulfur group element is 50 mass ppm or less, and a concentration of sulfur is 5 mass ppm or more and 12 mass ppm or less, a concentration of selenium is 5 mass ppm or more and 20 mass ppm or less, or a concentration of tellurium is 15 mass ppm or more and 50 mass ppm or less, and the palladium-coated copper bonding wire including a palladium-concentrated region with the average concentration of palladium of 6.5 atom % or more and 30.0 atom % or less relative to the total of copper and palladium within a range from a surface of a tip portion of a free air ball formed at a tip of the wire to 5.0 nm or more and 100.0 nm or less.

There is provided a palladium-coated copper bonding wire that does not cause a shrinkage cavity during first bonding, has high bonding reliability, and is capable of maintaining excellent bonding reliability for a long period of time even in high-temperature and high-humidity environments. A palladium-coated copper bonding wire in which a concentration of palladium is 1.0 mass % or more and 4.0 mass % or less relative to the total of copper, palladium, and a sulfur group element, a total concentration of the sulfur group element is 50 mass ppm or less, and a concentration of sulfur is 5 mass ppm or more and 12 mass ppm or less, a concentration of selenium is 5 mass ppm or more and 20 mass ppm or less, or a concentration of tellurium is 15 mass ppm or more and 50 mass ppm or less, and the palladium-coated copper bonding wire including a palladium-concentrated region with the average concentration of palladium of 6.5 atom % or more and 30.0 atom % or less relative to the total of copper and palladium within a range from a surface of a tip portion of a free air ball formed at a tip of the wire to 5.0 nm or more and 100.0 nm or less.

A mounting structure includes a BGA including a BGA electrode, a circuit board including a circuit board electrode, and a solder joining portion which is arranged on the circuit board electrode and is connected to the BGA electrode. The solder joining portion is formed of Cu having a content ratio in a range from 0.6 mass % to 1.2 mass %, inclusive, Ag having a content ratio in a range from 3.0 mass % to 4.0 mass %, inclusive, Bi having a content ratio in a range from 0 mass % to 1.0 mass %, inclusive, In, and Sn. A range of the content ratio of In is different according to the content ratio of Cu.