1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Solar cell

  1. Feb 3, 2005 #1
    When power is generated in a solar cell, it is because of irradiance of radiation on a pn-junction. But in which part of the junction are the electron-hole pairs created? Is it just the depleted region or are they also created in the n- and p-type semiconductors?

    An engineer's response would be for me to consider a current source in parallel with a diode but I need a physicists response. What the heck is going on in a solar cell?

    I'd be grateful for any help, thanks.
  2. jcsd
  3. Feb 4, 2005 #2


    User Avatar
    Homework Helper
    Gold Member

    The electron-hole pairs can be generated anywhere in a semiconductor, but they would recombine at once and nothing would happen unless they were formed in the depleted region and sucked away at opposite directions by the "built-in" electric field there. You know that positive charges are accumulated at the n type side near the junction and negative charges at the p type side. So the electron-hole pair will be separated, the electron moving into the n side and the hole moving into the p side. This results excess charge on both sides, and connecting the terminals you get current.

  4. Feb 4, 2005 #3
    Thank-you echild. That answer is quite helpful.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?