| 摘要 |
PURPOSE:To remove selectively Sn or an Sn alloy from a Cu substrate in a short time without damaging the substrate by adding specified amounts of complex ion contg. F and F ion. CONSTITUTION:This removing soln. for Sn and Sn alloys contains 0.1-350g/l complex ion contg. F and 0.05-150g/l F ion when expressed in terms of F. BF4<->, TiF6<2->, SiF6<2->, AlF6<3-> or the like is used as the complex ion contg. F. It is preferable to add a heterocyclic compound contg. an N atom as a ring forming member in the form of =NH or identicalN and contg. no S atom to the acidic removing soln. The heterocyclic compound is pyrazole, imidazole, triazole or the like, and a deriv. thereof may be used. |
