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PCB007-Sept2019

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14 PCB007 MAGAZINE I SEPTEMBER 2019 Morgan: There was a time when people said, "Shut up. Don't talk about this. We don't want to hear it." But now they're saying, "We agree with you, but we don't know how to do it." Goodwin: It is moving forward. Morgan: It's being discussed a lot now, and I talk about it every chance I get, and other peo- ple are too now, so it's coming around. Matties: If we, as an industry, embraced this concept to go with a performance-based stan- dard, what timeframe would we be looking at for a full conversion? Goodwin: The first step, in my opinion, would be to remove all references to resin chemis- try from the existing specification. That could be done relatively easily. IPC could become about performance, so removing the chemistry would be a great step forward. In the end, is it a REACH compliant chemistry, for example? Yes or no is all we need to know. Morgan: What I'd probably tend to do is to leave the system currently as it is because to rewrite it is going to be pretty hard. I'd pre- fer to start again. I'd leave the stuff in there that we have, start with a new initiative, find a group of people who have an interest in this, and then write at least a basic set. You could then have one for low-loss or high-frequency electronics and one for high reliability. Imag- ine maybe four or five categories of general performance, not even application-specific at this stage. And then say, "If we go to write a specification for high reliability-based materi- als, what kind of things do you want to put in there? What are the properties?" Goodwin: I want to have a relatively high Tg. Morgan: Exactly. What should the T-260 be? It should be an hour minimum. What about the Tg? Let's say 175 minimum. What about the Dk? We don't care about that too much, so let's put a value of 4.5 maximum. You'd go through all the list of all the things that we Nolan Johnson: We have end users who are es- sentially designers, but the authors in charge of this process tend to be on the manufacturer side; they have a different set of criteria they consider important. The audience here, the de- signers, aren't particularly well represented in the standards process. Morgan: There is vested interest as well. In ev- ery single meeting I used to go to, the whole intention was to make sure your materials were included in all of the specifications. There's a vested interest to make sure that your stuff, whatever you supply, meets the standard that you've all agreed upon, which is why it's for the manufacturers. Goodwin: To add to that, having been to certain meetings with very specific discussions about standards, there are no definitions of some terms, so it's not even a standard. Morgan: These are like methods for specifying or process standards, so they're not standards in the way that IEC standards are. So, you're right that they're not primary standards; they are the lowest common denominator. Goodwin: It's like the secondary resin thing; there is no published definition. And when I talk with people, everyone takes their own view. Morgan: It's fun for me as a materials technolo- gist to discuss this with people who don't have the first idea what any of this is, and that's what happens. All they know is that it suits their company to say a certain thing, and that is a problem you always get. I suppose IEC standards do somewhat better because they are international. You don't have companies represented there; you have countries repre- sented, so a country would decide who its ex- perts are and put them forward. An additional issue is that the people who do this work are getting older, and they're a limited pool. Matties: The more we discuss it and make it visible to the industry, the more energy it will have.

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