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Doping Defects in Semiconductors?

  1. Jul 21, 2014 #1
    How is it that certain electronic goods are designed to fail? Planned Obsolescence is just that, planned. So what goes into designing failing systems of computer?

    Hypothesis: Perhaps there are defects in the n and p-type doped semiconductors. The lattice entropy increases over time producing defects in the semiconducting material. The joule heating of any electronic device supplies the energy to increase entropy. So if one could design an electronic system to dissipate and increasing amount heat over time then more defects in the semiconductors will occur. The question is do computers dissipate more heat over time? When does a computer typically fail?
  2. jcsd
  3. Jul 22, 2014 #2

    Simon Bridge

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    Planned Obsolescence means planning for obsolescence - not "designing a component to fail".
    All materials fail at some stage - it is sensible to plan for that.
    This means replacing components before they fail - that is, we make them obsolete in a fixed time as a matter of policy rather than wait for them to fail and, say, crash the plane.

    It is also sensible to take the expected lifetimes of components into account when designing a device.
    There is no point just using the most long-lived of every component if the shortest lived one lasts about 1% of the longest lived one. That is just a waste of resources.

    You should be able to answer the questions you posed yourself - you have used computers: do they dissipate more heat over time? How long do computers last? Hint: read the guarantee.
  4. Jul 22, 2014 #3


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    You do know that heating silicon reduces the lattice defect density, right?
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