Au—Sn—Ag-based solder alloy and solder material, electronic component sealed with the same Au—Sn—Ag based solder alloy or solder material, and electronic component mounting device

An Au—Sn—Ag-based solder alloy containing Au, Sn, Ag and elements that are inevitably contained owing to a procedure for manufacturing,

• wherein the Au—Sn—Ag-based solder alloy has a composition adjusted so that a solidus temperature is within a range of 280 to 400° C. with a gap between the solidus temperature and a liquidus temperature being within 40° C.,
• wherein the Au—Sn—Ag-based solder alloy contains Sn of 21.1 mass % or more and less than 31.0 mass %, Ag of 0.1 mass % or more and 12.5 mass % or less, and a balance of Au except for the elements that are inevitably contained owning to the procedure for manufacturing, and
• wherein the Au—Sn—Ag-based solder alloy has a lamellar structure as a eutectic portion of 5 μm or finer.