Patent ID: 6476487
Filing Date: 2002-11-05
Classification: B23K,H01L,H05K

Abstract:
An electronic part having a fine solder pattern whose thickness is not less than 5 &mgr;m and not more than 200 &mgr;m, and whose thickness standard deviation &sgr; is not more than 14, obtained by a method which comprises the steps of:I: selectively imparting tackiness to only a part of a metallic surface of an article by means of a reaction caused by contacting a tacky layer-forming solution with the part of the metallic surface, II: adhering a Pb-free powdered solder selectively only to the resulting tacky portion by spreading the powdered solder on the article, and III: then melting the solder by heating to thereby form a solder film on the part of the metallic surface.