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| newPhis |
Posted: May 19 2005, 07:02 PM
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Newbie ![]() Group: Members Posts: 2 Joined: 19-May 05 Positive Feedback: 0% Feedback Score: 0 |
Does anyone knows what hapens (I mean in materijal change) if semiconductor s get overheat and get destroyed. ?
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| Guest |
Posted: May 19 2005, 07:56 PM
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Well when a Semiconducter chip overheats... its IC's and circuits will melt down. Causing the chip to fail.... lol Then you would normally dispose of it after that
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| DarK SparX |
Posted: May 19 2005, 07:59 PM
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Newbie ![]() Group: Members Posts: 10 Joined: 22-April 05 Positive Feedback: 0% Feedback Score: 0 |
"Well when a Semiconducter chip overheats... its IC's and circuits will melt down. Causing the chip to fail.... lol Then you would normally dispose of it after that "
Haha I forgot to log in |
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| newPhis |
Posted: May 23 2005, 08:07 PM
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Newbie ![]() Group: Members Posts: 2 Joined: 19-May 05 Positive Feedback: 0% Feedback Score: 0 |
Nobody dont knows why semiconductor does not work when get destroyed ?
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| icecycle |
Posted: May 24 2005, 01:37 AM
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Member ![]() ![]() Group: Members Posts: 141 Joined: 18-March 05 Positive Feedback: 0% Feedback Score: 0 |
Well, I am tempted to post a picture of a modem circuit board after a lightning strike.
Carbon, silicon, those things, burn. They get a lot of oxygen atoms integrated in to them. See, a transistor is a little thing that has a very small area that is composed of two compounds that cannot work when it is burned (has combined with oxygen.) Think what happens when you run your car into a tree, suddenly it has cellulose combinded with your front bumper. Why, does it not run? Then think very small. You have microscopic bits of tree limb in your chip. |
| geistkiesel |
Posted: Jul 11 2005, 12:27 PM
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Newbie ![]() Group: Members Posts: 23 Joined: 17-May 04 Positive Feedback: 0% Feedback Score: 0 |
NePhis, As I see it two basic things can occur. 1. If the heat is too great the semiconductor devices that are affected will be destroyed. 2. If the heat does not destroy the devices, transitors, diodes etc, the electronic charateristics of those devices can be perturbed and the system will not operate as designed. The devices are embedded in silicon (for example) by a complex process that requires multiple diffusions of dopants that change the electrical characteristis (p-type, n-type). If, for example you are using phosphorus to make your silicon "p" type, acceptor, the phosphorus will undergo a series of diffusions where each heating cylce extends the depth and width the phospohorus has diffused into the silicon. When manufacturing the chip, say integrated circuit, this process has been carefully tested where the diffusion length of each step is known. That is, if the circuit requires a number diffusion steps, say five, then after the completed diffusions the phospohorus has now reached its designed depth and width. Now, if the chip is subjected to some intense heat that does not destroy the chip, the phosphorus will diffuse further into the silicon and maybe even extending to the next or closest device such that the designed function becomes scarmbled and the circuit, while perhaps operable, will not function as designed. The reult will be unexpected electronic results that will necessitate the removal of the over diffused circuit and repalced with a new chip. Theoretically a large number of fairly low temperature gradients can operate to accumulate an over diffused condition giving unexpected electronic results. Geistkiesel |
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