Issue link: https://iconnect007.uberflip.com/i/1038326
14 PCB007 MAGAZINE I OCTOBER 2018 Matties: Where is Ludy based? Stepinski: Pirmasens, Germany. We use a differ- ent concept; we do the regular free-plate pro- cess here, and then all copper cells are down there. Over here, we have the option for nickel and gold plating, and we do the resist stripping in the line. We're doing vertical resist stripping and vertical differential etching for SAP prod- ucts. As a result, the parts come out fully cir- cuitized. That's a unique feature. Also, every tank has eight pumps. Do you see all of the controls? Matties: Yes, so you can really dial it in? Stepinski: Absolutely. Initially, we have six ac- tive tanks. They each hold eight panels, so 48 panels can be plated at one time. It's a big line. It's the most advanced vertical line anyone has ever done in North America from our under- standing. Matties: When will this be operational? Stepinski: August. We're going to start plating the first two chemistries, which are the high as- pect ratio electrolyte and a semi-additive plate that does blind via fill at the same time—both from Atotech. The intention is to have one cell for very high aspect ratios up to 40:1 or 50:1, and the SAP process for the very fine line and space and microvias—substrate-like PCB (SLP) stuff. In the other cell, we'll have a bath that only does thick panel microvias. Because the horizontal equipment only goes up to 2.4 mm, we'll have one cell configured for higher thick- nesses. Matties: Your approach to etching is different. Stepinski: Our etch process is different. Ev- erybody else tries to do vacuum etching with some weird programming stuff on the top side. Instead, we etch everything from the bottom. Matties: Makes sense. Stepinski: It's 40% faster from the bottom with no puddling at all. We see about 20% of the variation you'd normally get from top-side etching. There are no moving parts—every- thing is fixed in place—so nothing can fail. Figure 3: The Ludy vertical line at GreenSource shown here is nearing completion. Once operational, it is expected to be capable of microvia aspect ratios up to 40:1 and beyond. Click to watch flyover drone video.