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Technology Stocks : Wolf speed -- Ignore unavailable to you. Want to Upgrade?

To: EvanG who wrote (10527)	8/16/2022 10:14:49 AM
From: slacker711	1 Recommendation Recommended By OldAIMGuy Read Replies (1) \| Respond to of 10712

Even Wolfspeed's last analyst day presentation was fishy because when it came to talking about defect rates it was worded as if the best substrate we could find had these statistics. FWIW, Palmour didn't give general stats, but he did say that the quality that they were seeing at 200mm was better than their commercial 150mm wafers. They have said similar things about 200mm component yields on their R&D line but hard data is rare from the company. I don't expect much data on the ramp tomorrow but we'll see if they can give any substantive comments about customer qualification. So from a crystal and structural standpoint, it's really a phenomenally good wafer. Now I'm going to talk about some other things you look at that don't show. So there's dislocations we don't like that cause some yield loss, et cetera. One of them is called a basal plane dislocation or BPD in the industry is typically what they call it. We actually have a very low density of these, 309 per square centimeter. Another dislocation, we're always working to reduce is called a threading screw dislocation. We're down to 289 per square centimeter. These are very, very good numbers. These are very good numbers for 150mm. In general, I would say the quality that we're seeing out of the 200mm is actually better than what we're currently cranking out on a very high volume today for 150-millimeter. Still early in the game. We have to bring down the cost per square centimeter. But quality-wise, we're there. I mean it's -- now our goal is really to be able to make this quality and figure out how to make it cheaper and cheaper. Now once you have the crystal, you actually have to polish it.