METHOD FOR PRODUCING Sn-CONTAINING POWDER, Sn-CONTAINING POWDER PRODUCED BY THE METHOD, AND PASTE FOR SOLDER USING THE Sn-CONTAINING POWDER

摘要

PROBLEM TO BE SOLVED: To provide a method for Sn-containing powders which are suitable as solder powders, are hardly aggregated with each other, and have satisfactory meltability without disturbing a metal element diffusion among powders, and to provide Sn-containing powders produced by the method.;SOLUTION: In the method for producing Sn-containing powders, whose volume cumulative median diameter; D50 is 5 m, the Sn-containing powders are produced by using a bivalent chromium ion solution as a reducing agent, and adding the bivalent chromium ion solution to a metal salt solution containing the metal composing the powders in the presence of a dispersant suppressing the flocculation of Sn-containing powders so as to reductively precipitate the metal composing the powders, the containing ratio of Sn in the Sn-containing powders is 94 mass%. As for the dispersant, in the case thermogravimetric analysis is performed in an Ar gas atmosphere under conditions satisfying temperature rising velocity of 10 C/min, weight reduction percentage in the range from the melting point T_m of the metal composing the Sn-containing powder to (the melting point T_m+40)C is 60%.;COPYRIGHT: (C)2010,JPO&INPIT