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Fabrication of Single GaAs Solar Cell by MBE

  1. Sep 20, 2010 #1
    Fabrication of Single Junction GaAs Solar Cell by MBE

    Hi All,

    My project is to produce 1 single piece of GaAs solar cell (about the size of 1cm square) by MBE technique. I have gone through some read up and simulation software software called atlas by silvaco. for time being, I am testing on other sample to do the thermal evaporation and photo lithography. how ever my question is.

    how do i connect the bottom contact layer with the top electrode layer so as to achieve maximum current for my I V characteristic measurement.

    I have some very rough sample shown in the picture below, and I try to search through the net but to no avail. I would be most grateful if you guys could give me some valuable inputs.
    http://img137.imageshack.us/img137/4448/solarcell.jpg [Broken]

    Uploaded with ImageShack.us

    The 2 fine wires on top is the gold wires (cathode) the bottom is connected to copper foil (anode)
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Sep 20, 2010 #2


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    It this a multi-junction cell? Is the substrate also GaAs, or something else? Can you draw a simple schematic of the device geometry?
  4. Sep 20, 2010 #3
    sorry for the incomplete info.
    is a single junction with GaAs (100) as substrate
    here is the picture.
    as for the dopant concentration, and layers thickness. it is still yet to finalize, as I'm still working on dummy sample set. thanks.

    http://img819.imageshack.us/img819/1641/76048936.jpg [Broken]

    Uploaded with ImageShack.us
    Last edited by a moderator: May 4, 2017
  5. Sep 29, 2010 #4
    you need to minimize the contact resistance. you might make separate contacts to both front and back and keep trying until your contact resistance is few ohms. is there AR coating on the small wires, or do you need to solder to the bigger bus bar.
  6. Sep 30, 2010 #5
    Hi Kevin75081,

    Thanks, so the point is to trying out the materials and thickness to have a contact resistance of few ohms? I will first do without AR coating and measure the contact resistance. right now the contact to the bus bar is by soldering to a 0.02 diameter gold wire.

    without the AR coating is because I have yet to final the method to align the AR coating mask with the grid mask.
  7. Oct 2, 2010 #6
    Re: Fabrication of Single Junction GaAs Solar Cell by MBE

    Is As toxic?
    Last edited by a moderator: May 5, 2017
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