Abstract: A lead-free solder alloy capable of forming solder joints in which electromigration and an increase in resistance during electric conduction at a high current density are suppressed has an alloy composition consisting essentially of 1.0-13.0 mass % of In, 0.1-4.0 mass % of Ag, 0.3-1.0 mass % of Cu, a remainder of Sn. The solder alloy has excellent tensile properties even at a high temperature exceeding 100° C. and can be used not only for CPUs but also for power semiconductors.

Abstract: Provided is a solder alloy having excellent wettability on both of a Cu surface and an Ni surface. The solder alloy has such an alloy composition that 0.6 to 0.9 mass % of Cu and 0.01 to 0.1 mass % of Al are contained, 0.02 to 0.1 mass % of Ti and/or 0.01 to 0.05 mass % of Co may be contained as required and the remainder is made up by Sn.

Abstract: A lead-free solder alloy capable of forming solder joints in which electromigration and an increase in resistance during electric conduction at a high current density are suppressed has an alloy composition consisting essentially of 1.0-13.0 mass % of In, 0.1-4.0 mass % of Ag, 0.3-1.0 mass % of Cu, a remainder of Sn. The solder alloy has excellent tensile properties even at a high temperature exceeding 100° C. and can be used not only for CPUs but also for power semiconductors.

Abstract: By using a solder alloy consisting essentially of 0.2-1.2 mass % of Ag, 0.6-0.9 mass % of Cu, 1.2-3.0 mass % of Bi, 0.02-1.0 mass % of Sb, 0.01-2.0 mass % of In, and a remainder of Sn, it is possible to obtain portable devices having excellent resistance to drop impact and excellent heat cycle properties without developing thermal fatigue even when used in a high-temperature environment such as inside a vehicle heated by the sun or in a low-temperature environment such as outdoors in snowy weather.

Abstract: A lead-free solder which can reduce the occurrence of voids and a connecting member which uses the solder and has excellent adhesion, bonding strength, and workability are provided. The lead-free solder alloy contains Sn: 0.1-3% and/or Bi: 0.1-2%, and a remainder of In and unavoidable impurities and has the effect of suppressing the occurrence of voids at the time of soldering. The connecting member is prepared by melting the lead-free solder alloy, immersing a metal substrate in the melt, and applying ultrasonic vibrations to the molten lead-free solder alloy and the metal substrate to form a lead-free solder alloy layer on the surface of the metal substrate. A heat sink and a package are soldered to each other through this connecting member by reflow heating in the presence of flux.

Abstract: Provided is a process for mounting a BGA (Ball Grid Array) or CSP (Chip Size Package) on a printed circuit board. The process includes melting and fusing together solder paste and a solder ball. The solder ball has a solder composition that includes 0.5-1.1 mass % of Ag, 0.7-0.8 mass % of Cu, 0.05-0.08 mass % of Ni, and a remainder of Sn. In the process, the solder ball is placed on an electrode of the BGA or CSP substrate and the solder paste is applied onto an opposing electrode of the printed circuit board.

Abstract: A lead-free solder ball for electrodes of a BGA or CSP comprising 0.5-1.1 mass % of Ag, 0.7-0.8 mass % of Cu, 0.05-0.08 mass % of Ni, and a remainder of Sn. Even when a printed circuit board to which the solder ball is bonded has Cu electrodes or Au-plated or Au/Pd-plated Ni electrodes, the solder ball has good resistance to drop impacts. The composition may further contain at least one element selected from Fe, Co, and Pt in a total amount of 0.003-0.1 mass % or at least one element selected from Bi, In, Sb, P, and Ge in a total amount of 0.003-0.1 mass %.

Abstract: Provided is a process for mounting a BGA (Ball Grid Array) or CSP (Chip Size Package) on a printed circuit board. The process includes melting and fusing together solder paste and a solder ball. The solder ball has a solder composition that includes 0.5-1.1 mass % of Ag, 0.7-0.8 mass % of Cu, 0.05-0.08 mass % of Ni, and a remainder of Sn. In the process, the solder ball is placed on an electrode of the BGA or CSP substrate and the solder paste is applied onto an opposing electrode of the printed circuit board.

Abstract: Solder used for flip chip bonding inside a semiconductor package was a Sn—Pb solder such as a Pb-5Sn composition. Lead-free solders which have been studied are hard and easily form intermetallic compounds with Sn, so they were not suitable for a flip chip connection structure inside a semiconductor package, which requires stress relaxation properties. This problem is eliminated by a flip chip connection structure inside a semiconductor package using a lead-free solder which is characterized by consisting essentially of 0.01-0.5 mass percent of Ni and a remainder of Sn. 0.3-0.9 mass percent of Cu and 0.001-0.01 mass percent of P may be added to this solder composition.

Abstract: A lead-free solder alloy capable of forming solder joints in which electromigration and an increase in resistance during electric conduction at a high current density are suppressed has an alloy composition consisting essentially of 1.0-13.0 mass % of In, 0.1-4.0 mass % of Ag, 0.3-1.0 mass % of Cu, a remainder of Sn. The solder alloy has excellent tensile properties even at a high temperature exceeding 100° C. and can be used not only for CPUs but also for power semiconductors.

Abstract: Provided is a solder alloy having excellent wettability on both of a Cu surface and an Ni surface. The solder alloy has such an alloy composition that 0.6 to 0.9 mass % of Cu and 0.01 to 0.1 mass % of Al are contained, 0.02 to 0.1 mass % of Ti and/or 0.01 to 0.05 mass % of Co may be contained as required and the remainder is made up by Sn.

Abstract: A Sn—Ag—Cu based solder alloy capable of increasing the connection reliability of a solder joint when evaluated in a high temperature environment is provided. The alloy has an alloy composition consisting essentially of, in mass percent, Ag: 1.0-5.0%, Cu: 0.1-1.0%, Sb: 0.005-0.025%, Fe: 0.005-0.015%, and a remainder of Sn. The Fe content in mass percent is 0.006-0.014%. The Sb content in mass percent is 0.007-0.023%. Preferably Fe:Sb as a mass ratio is 20:80-60:40. The total content of Fe and Sb is preferably 0.012-0.032%.

Abstract: A semiconductor device is provided which has internal bonds which do not melt at the time of mounting on a substrate. A bonding material is used for internal bonding of the semiconductor device. The bonding material is obtained by filling the pores of a porous metal body having a mesh-like structure and covering the surface thereof with Sn or an Sn-based solder alloy.

Abstract: A lead-free solder which can reduce the occurrence of voids and a connecting member which uses the solder and has excellent adhesion, bonding strength, and workability are provided. The lead-free solder alloy has a composition consisting essentially of Sn: 0.1-3% and/or Bi: 0.1-2%, and a remainder of In and unavoidable impurities and has the effect of suppressing the occurrence of voids at the time of soldering. The connecting member is prepared by melting the lead-free solder alloy, immersing a metal substrate in the melt, and applying ultrasonic vibrations to the molten lead-free solder alloy and the metal substrate to form a lead-free solder alloy layer on the surface of the metal substrate. A heat sink and a package are soldered to each other through this connecting member by reflow heating in the presence of flux.

Abstract: By using a solder alloy consisting essentially of 0.2-1.2 mass % of Ag, 0.6-0.9 mass % of Cu, 1.2-3.0 mass % of Bi, 0.02-1.0 mass % of Sb, 0.01-2.0 mass % of In, and a remainder of Sn, it is possible to obtain portable devices having excellent resistance to drop impact and excellent heat cycle properties without developing thermal fatigue even when used in a high-temperature environment such as inside a vehicle heated by the sun or in a low-temperature environment such as outdoors in snowy weather.

Abstract: A lead-free solder alloy is provided which has improved impact resistance to dropping even after thermal aging and which is excellent with respect to solderability, occurrence of voids, and yellowing. A solder alloy according to the present invention consists essentially of, in mass percent, (1) Ag: 0.8-2.0%, (2) Cu: 0.05-0.3%, (3) at least one element selected from In: at least 0.01% and less than 0.1%, Ni; 0.01-0.04%, Co: 0.01-0.05%, and Pt: 0.01-0.1%, optionally (4) at least one element selected from Sb, Bi, Fe, Al, Zn, and P in a total amount of up to 0.1%, and a remainder of Sn and impurities.

Abstract: A lead-free solder ball for electrodes of a BGA or CSP comprising 0.5-1.1 mass % of Ag, 0.7-0.8 mass % of Cu, 0.05-0.08 mass % of Ni, and a remainder of Sn. Even when a printed circuit board to which the solder ball is bonded has Cu electrodes or Au-plated or Au/Pd-plated Ni electrodes, the solder ball has good resistance to drop impacts. The composition may further contain at least one element selected from Fe, Co, and Pt in a total amount of 0.003-0.1 mass % or at least one element selected from Bi, In, Sb, P, and Ge in a total amount of 0.003-0.1 mass %.

Abstract: A Sn—Ag—Cu based solder alloy capable of increasing the connection reliability of a solder joint when evaluated in a high temperature environment is provided. The alloy has an alloy composition consisting essentially of, in mass percent, Ag: 1.0-5.0%, Cu: 0.1-1.0%, Sb: 0.005-0.025%, Fe: 0.005-0.015%, and a remainder of Sn. The Fe content in mass percent is 0.006-0.014%. The Sb content in mass percent is 0.007-0.023%. Preferably Fe:Sb as a mass ratio is 20:80-60:40. The total content of Fe and Sb is preferably 0.012-0.032%.

Abstract: A semiconductor device is provided which has internal bonds which do not melt at the time of mounting on a substrate. A bonding material is used for internal bonding of the semiconductor device. The bonding material is obtained by filling the pores of a porous metal body having a mesh-like structure and covering the surface thereof with Sn or an Sn-based solder alloy.

Abstract: A lead-free solder which can reduce the occurrence of voids and a connecting member which uses the solder and has excellent adhesion, bonding strength, and workability are provided. The lead-free solder alloy has a composition consisting essentially of Sn: 0.1-3% and/or Bi: 0.1-2%, and a remainder of In and unavoidable impurities and has the effect of suppressing the occurrence of voids at the time of soldering. The connecting member is prepared by melting the lead-free solder alloy, immersing a metal substrate in the melt, and applying ultrasonic vibrations to the molten lead-free solder alloy and the metal substrate to form a lead-free solder alloy layer on the surface of the metal substrate. A heat sink and a package are soldered to each other through this connecting member by reflow heating in the presence of flux.