Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Question about pn diodes and their lifetime

  1. Jan 18, 2016 #1
    I was wondering, does the lifetime of a diode depend on how long it takes for all the free P electrons to transfer over to the p holes? In other words, do the electrons that fall into the p holes ever return to the n side?
  2. jcsd
  3. Jan 19, 2016 #2


    User Avatar
    2017 Award

    Staff: Mentor

    It depends on the current applied, they can also leave the diode. Other electrons come in from the other side, so there is never a lack/surplus of electrons. There is no "lifetime" in that sense. You can fry a diode if it gets too hot, you can kill it with radiation damage, mechanical damage and a few other things, but apart from that diodes live forever. Electron flow is always balanced.
  4. Jan 20, 2016 #3
    Electrons come and go, it's the ions that stay. The diode is destroyed when the crystal structure with the p and n doping gets destroyed, e.g. by overheating. Just as mfb said above.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook