Issue link: https://iconnect007.uberflip.com/i/1369942
MAY 2021 I DESIGN007 MAGAZINE 85 Litson: As I consider how to best apply this tech- nology, material compatibility is an important aspect. It is important to know that a new pro- cess is going to be compatible with nearly all materials. Next, I'm looking into the electrical aspects of these new geometries. I also look at proven reliability parameters: the A-SAP process passed peel strength, IST cou- pon testing, and signal integrity analysis across a variety of materials. Dunn: Working with something new can be exciting and just a little intimidating. Navigat- ing the learning curve, do you see any chal- lenges for designing with this new technology in mind? Litson: In my opinion, designers should remem- ber their basic electronics—it influences every- thing we do. We must understand the physics to make certain we know what will be affected. With these new parameters, we will need to go back and take another look at our calculations, which are based on the resistance of copper which is based on the area. en bring into the equations the resistance of the dielectric mate- rials, layer structures, etc. I am curious to see how the geometry of the conductors shis the electrical results. Because each product is different, there are few set-in-stone design rules for semi-additive processed layer-only guidelines. e most important guideline: this process requires close collaboration between design and fabri- cation. For additional guidance, a collection of case studies would be great, maybe online as a dynamic design guide. Just brainstorming! Dunn: An online dynamic design guide is a great idea. Taking a step back from design, why do you feel that this new technology is important to the industry? Litson: I think this is important to the indus- try for several reasons. One is implementa- tion of this process—it is designed to integrate Figure 3: Many designs are being driven to require line and spaces at 50 µm due to smaller pin spacing on components and smaller package products.