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Technology Stocks : Intel Corporation (INTC) -- Ignore unavailable to you. Want to Upgrade?

To: Jeff Fox who wrote (66156)	10/9/1998 7:48:00 PM
From: Tony Viola	Read Replies (4) \| Respond to of 186894

Jeff, Maverick wafers, IBM. IBM feels strongly (knows) that chips harvested and packaged from low yielding wafers will be poorer WRT short, medium and long term reliability. They've learned this over the years through tons of data gathering, factory and field, and talk about it, and other not so well known things, at seminars and workshops. What the heck, their IC processing and manufacturing prowess are so good and well known, they have nothing to lose. Why they believe in the precept in my first sentence above is because they know that the same defects that cause die to be rejected at wafer sort time are present in the "good" ones as well as in the bad ones, to some degree. It's just that they aren't bad enough YET to make the "good" ones fail. They believe that, over time, the pin hole or metal defects will grow until they cause, e.g., a short and a catastrophic failure. So, as the computer controlled wafer sort tester is stepping along, it's keeping track of yield. If, after it gets through some percentage of the wafer, the yield is less than a programmed amount, testing stops and the whole wafer is thrown away. They call these wafers 'Mavericks'. Most companies probably package and sell die from any wafer that has any good ones at all. Not IBM. They are smart enough and rich enough to be able to nip those bound to fail ones in the bud, and only ship the ones that have a far greater chance of lasting a long, long time. One other thing about IBM. They claim that their chips never get to the right hand "wall" of the bathtub curve, they're so good. Actually, that's because the computers that the chips live in become obsolete (ten years or so) before the chips have a chance to fail. Chip Reliability 101 dismissed, Tony