Patent ID: 7309411
Filing Date: 2007-12-18
Classification: C25D,F16C

Abstract:
1. A process for electroplating a substrate with a tin alloy, which alloy comprises from about 2% by weight to about 15% by weight of alloying metal, said process comprising: a) contacting the substrate with an electroplating bath comprising: b) applying a current regime in which a direct current having a substantially constant current density is applied for a first time interval and a pulsed current is applied for a second time interval, wherein said first time interval and said second time interval are consecutive, wherein the pulsed current comprises a first pulse period at a first current density and a second pulse period in which the current density is substantially zero, wherein the first pulse period and the second pulse period are alternated, whereby a duty cycle of pulsed current is established; and wherein during the first time interval the alloying metal is deposited along with the tin and during the second time interval substantially only tin is deposited.