Motoyo Wajima <[log in to unmask]> さんは書きました: >Mr.Hammond > > A 1:1 aspect ratio of blind via is limit. > Vibration through electroless,electro plating process and lower current > density in electro plating are very important. > Regards >Motoyo Wajima >General Purpose Computer Division,Hitachi,Ltd.(JAPAN) > > >[log in to unmask] さんは書きました: >> I've heard that the general rule limiting blind vias is a 1:1 aspect >> ratio. You are at it with the 16 mil holes & 16 mil depth. It seems >> like you are doing the right things (i.e. vibration, etc.) so I'm not >> sure what else to suggest. >> >> >> MB >>_____________________________ Reply Separator >_________________________________ >>Subject: Blind vias & fine lines >>Author: [log in to unmask] at SMTPLINK-HADCO >>Date: 2/12/97 10:07 PM >> >> >>Techneters, >> Can anyone help? I am having two problem areas: >> >> 1) Blind via holes 16 mil diameter 16 mil deep contacting with 4 >>inner layers. I cannot always plate copper into all holes. If I do copper >>plate them I cannot tin plate all the holes. I have vibrators on the >>cathode movement frame and a giant to clout the fight bars with a 2 pound >>hammer. Is there anything else I can do?!? >> >> 2) Circuits with 2 mil track and gaps. The finish required is >>electroless nickel/immersion gold. How can this be done without causing >>the tracks to short with nickel spikes? >> >> Thanks in advance, >> Roger Hammond >> >>*************************************************************************** >>* TechNet mail list is provided as a service by IPC using SmartList v3.05 * >>*************************************************************************** >>* To unsubscribe from this list at any time, send a message to: * >>* [log in to unmask] with <subject: unsubscribe> and no text. * >>*************************************************************************** >>* If you are having a problem with the IPC TechNet forum please contact * >>* Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * >>*************************************************************************** >> >> >>*************************************************************************** >>* TechNet mail list is provided as a service by IPC using SmartList v3.05 * >>*************************************************************************** >>* To subscribe/unsubscribe send a message <to: [log in to unmask]> * >>* with <subject: subscribe/unsubscribe> and no text in the body. * >>*************************************************************************** >>* If you are having a problem with the IPC TechNet forum please contact * >>* Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * >>*************************************************************************** >> >> *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To subscribe/unsubscribe send a message <to: [log in to unmask]> * * with <subject: subscribe/unsubscribe> and no text in the body. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ***************************************************************************