To: Solon who wrote (1135 ) 9/28/2000 9:46:23 PM From: cosmicforce Respond to of 28931 I hope you were standing inside the pentagram! The pentagram is in my mind! As I was riding my bike today, I was pondering this stuff, I think I agree, mostly <g>. It isn't very practical in "real" life. But, as we miniaturize everything relatively unlikely stuff starts to invade. I had a power transistor fail once but, the failure was from the inside out. A hole the diameter of a small finishing nail was in the stainless steel case, clearly burned from the inside and creating a hole in the case. It was odd enough that I decided to open the can, expecting one of the wire-bond leads to have broken free and to have hit the case. That isn't what happened. Under 100x mag there was a hole resembling a crater in the wafer. The semiconductor material had vaporized in the hole. I told this to my boss, an experienced electrical engineer, who told me that there was a known failure mechanism in semiconductors in which, under rare conditions, a plasma jet could erupt from a sudden, instantaneous and catastrophic failure of the junction. In this failure mode, all at once there was a dump of charge from one side of the junction to the other at very high current densities, but in very narrow dimensions. The resulting jet of highly energetic plasma was more than 1/8" long to have penetrated the case. It is the only time I've ever seen one. And to date, it had been the only on he'd seen, but he had heard of them. I can't even count the number of transistor failures I've seen and this was by far the oddest failure of many hundreds. You can be real unlucky or lucky in life. I've seen improbably things happen and probable things not happen. This inversion is always unexpected if you expect things to go "as they should".