Dear All, Is the plating process deifferent for IC package substrate ? Regards Suganthi,CID Werner Engelmaier <[log in to unmask]> Sent by: TechNet <[log in to unmask]> 05/19/2006 05:27 PM Please respond to TechNet E-Mail Forum <[log in to unmask]>; Please respond to [log in to unmask] To [log in to unmask] cc Subject Re: [TN] Plating process Hi Suganthi, Well, for some PCBs there is also a Ni overplate. Basically, the processes after drilling the hole are: 1) desmear [either chemically or by plasma etching]; 2) catalysation; 3) electroless Cu flash; 4) electrolytic Cu plate, with rinse/wask steps in between. The Cu flash is required for electrical continuity for the electrolytic plating., which is carried out, very basically in an acid solution with the PCB as cathode between Cu-anodes from which the plating process removes Cu in ion form which move in the solution to the PCB and deposit as Cu-plating. The plating current density determines the rate of plating, additives determine how fast you can plate and still get Cu-plating with good physical properties. This is it in an nutshell--in practice things get more complicated. Werner --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------