Abstract A small amount of rare earth Ce was added to Sn-Cu-Ni solder alloy, and the solderability of Sn-0. 5Cu-0. 05Ni- xCe solders on Cu and Au/Ni/Cu substrates was determined by the wetting balance method. The effe...Abstract A small amount of rare earth Ce was added to Sn-Cu-Ni solder alloy, and the solderability of Sn-0. 5Cu-0. 05Ni- xCe solders on Cu and Au/Ni/Cu substrates was determined by the wetting balance method. The effects of atmosphere, temperature, substrate, and Ce addition on the solderability of Sn-Cu-Ni-xCe solder were studied, respectively, and Auger electron spectroscopy （ AES） analysis in the depth direction of the alloy was carried out to discuss the effect of Ce addition on the solderability. The results indicate that the greatest improvement on the solderability of Sn-Cu-Ni-xCe is obtai^d with around O. 05wt. % -0. 07wt. % Ce addition, for Ce element keeps high content in a specific area in the depth direction from the surface of Sn-Cu-Ni alloy, which decreases the surface tension of molten solder. It is also found that the solderability of Sn-Cu-Ni-xCe solder on Au/Ni/ Cu substrate is better than that on Cu substrate. In N2 atmosphere, the wetting times of Sn- Ca-Ni-xCe alloys are reduced by 10% - 35% , below 1 s at 260 ℃ on Ca substrate, and about 1s at 250 ℃ on Au/Ni/Ca substrate.展开更多
文摘Abstract A small amount of rare earth Ce was added to Sn-Cu-Ni solder alloy, and the solderability of Sn-0. 5Cu-0. 05Ni- xCe solders on Cu and Au/Ni/Cu substrates was determined by the wetting balance method. The effects of atmosphere, temperature, substrate, and Ce addition on the solderability of Sn-Cu-Ni-xCe solder were studied, respectively, and Auger electron spectroscopy （ AES） analysis in the depth direction of the alloy was carried out to discuss the effect of Ce addition on the solderability. The results indicate that the greatest improvement on the solderability of Sn-Cu-Ni-xCe is obtai^d with around O. 05wt. % -0. 07wt. % Ce addition, for Ce element keeps high content in a specific area in the depth direction from the surface of Sn-Cu-Ni alloy, which decreases the surface tension of molten solder. It is also found that the solderability of Sn-Cu-Ni-xCe solder on Au/Ni/ Cu substrate is better than that on Cu substrate. In N2 atmosphere, the wetting times of Sn- Ca-Ni-xCe alloys are reduced by 10% - 35% , below 1 s at 260 ℃ on Ca substrate, and about 1s at 250 ℃ on Au/Ni/Ca substrate.
