Solder alloy and solder joint

A solder alloy having an alloy composition consisting of, by mass %:

• Cu:
• more than 2.0% and less than 3.0%,
• Ni:
• 0.10% or more and less than 0.30%, and
• Ge:
• 0.0010 to 0.20%, with the balance being Sn,
• wherein the alloy composition satisfies the following relations (1) and (2):
• 2.700%≤Cu+Ni+Ge≤3.190% relation (1)
• 0.33≤Ge/Ni≤1.04 relation (2)
• wherein Cu, Ni, and Ge in the relations (1) and (2) each represent the contents (mass %) thereof in the alloy composition, and
• wherein the solder alloy comprises the following properties:
• a ΔT that is obtained by subtracting a solidus temperature from a liquidus temperature is less than 110° C.,
• no solder bridges or solder icicles are observed after flow soldering at a temperature of 255° C.,
• a tensile strength measured in accordance with JIS Z 3198-2 (2003) is 38 MPa or more,
• a dross weight is 25 g or less, and
• a dimension of copper wiring on a test sample is not reduced by half after immersion of seven times or more in jetting molten solder.