|
|
|
|
J U L Y 2 0 1 7 , I S S U E # 5 7
|
|
|
|
|
|
Quick Links
|
|
Products/Equipment:
|
|
|
|
|
|
|
|
|
|
|
 |
Inkjet Solder Mask: Redefining your Solder Mask Needs!
Now that Direct Imaging solder mask is hitting its stride in North America and Europe, the next step in technology will be inkjet solder mask. I recently visited a customer that has been working with this technology for several months and they have made significant strides
. The panels they showed me were very nice in that the solder mask defined pads looked excellent and the coating was smooth with no printing defects.
As I examined the panel and discussed the results with the customer we started to talk more about how the industry would accept this technology and how the solder mask requirements might need to be redefined.
Let's just start with the processing of solder mask. You will still need a good pre-clean to remove all oxides and contaminates from the surface, as you would with any solder mask process, but after that your process changes dramatically. Think of all the work that goes into setting up a screen printer to ensure coverage of traces and keeping ink out of the holes. All of that is gone with inkjetting. Tack dry ovens; setting up the times, temperatures and airflows, are all gone now. Imaging equipment and photo tools and everything that goes with that process; eliminated. The developing process; solutions, temperatures, times, cleanliness, disposition etc; all gone. Think of all these headaches going away. You are probably saying "Where is it?" And "I want it now!"
This technology is very close, but we need to consider some design rules, as well. How thick does the solder mask need to be on the laminate between copper pads? With current technology (spray, screen print and curtain coat) it is a function of the height of the copper pads and how much solder mask fills in between the two pads. With inkjet, you program how much solder mask will be printed on the substrate. So how much? This is just one of many questions that has to be answered by designers as we move forward with this technology.
For final solder mask properties, we know that we have to meet the IPC SM-840 specifications, UL flammability and NASA outgassing for aerospace, as well as high TCT resistance for automotive end users. However, we will continue to work to find out these more difficult questions regarding design rules and requirements.
For more information on inkjet solder mask, please contact Taiyo America for the latest developments!
|
|
Via Hole Filling Has Come A Long Way Baby
During a recent installation of a ITC THP35 Via Hole Filling machine, I started thinking back about the history of via hole filling and the path that has led us to the high performance, non-conductive, via hole filling our industry demands today. Back thirty plus years ago, there were no blind vias, sequential laminations or Cu plate over. We would tent vias with DFSM while applying the solder mask to the entire surface of the panel. Other than the occasional broken tent, you never gave it another thought and away you went. The vias were one big vacuum void with Cu plated barrels and 3-4 mil thick tents of DFSM top and bottom. The via pads were large and Cu plate was not really possible over the tents so the real estate around the via was lost.
Continued...
|
|
|
|
Talking with Micha Perlman, Orbotech's Senior Marketing Manager (PCB Division)
We are going to do something a little different this month. Instead of talking to a Taiyo America customer as we normally do, we are going to talk to one of our partners. In recent years, the team at Taiyo has been successfully collaborating with Orbotech on a number of different DI solutions for Orbotech's Direct Imaging equipment. As you may know, this partnership has proven very successful with the real winners being our customers. I spoke recently with Orbotech's Micha Perlman, the senior marketing manager for the PCB division.
| | | | | |
