Plating solution using sulfonium salt

A plating solution for electrodeposition comprising:

• (A) a soluble salt containing at least a stannous salt in an amount of 30 to 100 g/L;
• (B) an acid selected from an organic acid and an inorganic acid, or a salt of the acid, in an amount of 80 to 300 g/L;
• and
• (C) an additive, wherein
• the additive comprises a sulfonium salt in an amount of 0.1 to 10 g/L, the sulfonium salt having one or more of aromatic rings represented by a general formula (1) below,
• wherein, R1 and R2 in the formula (1) are identical or different, and are any one of a phenyl group, a hydroxyphenyl group, a tolyl group, a hydrogen atom, CnH2n+1, n being an integer from 1 to 5,
• Ph represents a phenyl group, and
• X represents a halogen.