Electrolytic Sn or Sn alloy plating solution and Sn or Sn alloy plating method

摘要

It is an object to provide a Sn or Sn alloy plating solution capable of low concentration Pb formation. An electrolytic Sn or Sn alloy plating solution for forming a plating material provided for solder bonding, and at least one sulfuric acid compound, one or more acids selected from Sn salts, inorganic acids, organic acids and water-soluble salts thereof or water-soluble salts thereof, and an interface An electrolytic Sn containing an activator, wherein the sulfur-based compound is a thiol compound represented by the following general formula (Formula A), a salt of a thiol compound (Formula A), or a disulfide compound (Formula B), or Sn alloy plating solution.