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===Solar Cells===
 
===Solar Cells===
 
=====Solar Basics=====
 
=====Solar Basics=====
A solar cell is created to do one paramount task.  That is the production of [[electricity]] through the absorption of photons.  When light, in this case radiant energy from the sun, strikes the cell, a certain portion of it is absorbed within the semiconductor material. The semiconductor material in this case is that of the gallium arsenide.  This means that the energy of the absorbed light is transferred to the semiconductor, in our case the gallium arsenide.  The energy excites electrons, knocking them loose or otherwise removing them from their previous bound state.  This allows them to flow freely.  Solar and photo voltaic cells also have one or more electric fields that act as a mediator.  This field forces electrons liberated by light absorption to flow in a certain direction.  This flow of electrons, like many others, is a current.  This current can be harnesssed by placing metal contacts on the top and bottom of the cell.  With these newly placed contacts the current can be drawn off to power just about any external application.
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A solar cell is created to do one paramount task.  That is the production of [[electricity]] through the absorption of [[photons]].  When light, in this case radiant energy from the sun, strikes the cell, a certain portion of it is absorbed within the [[semiconductor]] material. The [[semiconductor]] material in this case is that of the [[gallium arsenide]].  This means that the [[energy]] of the absorbed [[light]] is transferred to the [[semiconductor]], in our case the [[gallium arsenide]].  The [[energy]] excites [[electrons]], knocking them loose or otherwise removing them from their previous bound state.  This allows them to flow freely.  Solar and photo voltaic cells also have one or more electric fields that act as a mediator.  This field forces [[electrons]] liberated by light absorption to flow in a certain direction.  This flow of electrons, like many others, is a current.  This current can be harnesssed by placing metal contacts on the top and bottom of the cell.  With these newly placed contacts the current can be drawn off to power just about any external application.
    
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Image:SolarCellOperation.jpg|Fig 2: is a diagram that showcases how the current flows in a solar cell as rays of light or photons (the yellow arrows) strike the cell.  Again the section labeled "A" is the n-type junction while the section labeled "B" is a p-type junction.  The section labeled "C" is the load for the circuit.  The electrons will flow starting at point "B" to point "A" then through the load "C."  Then the electrons will complete the loop and return in a clockwise loop to point "B."
 
Image:SolarCellOperation.jpg|Fig 2: is a diagram that showcases how the current flows in a solar cell as rays of light or photons (the yellow arrows) strike the cell.  Again the section labeled "A" is the n-type junction while the section labeled "B" is a p-type junction.  The section labeled "C" is the load for the circuit.  The electrons will flow starting at point "B" to point "A" then through the load "C."  Then the electrons will complete the loop and return in a clockwise loop to point "B."
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Image:SolarCellLightPath.jpg|Fig 3: is a diagram of how light (the yellow line) enters the solar cell.  It first passes through "A" which is the anti-reflective layer of the cell.  The sunlight then travels through, "B," the material the cell is made of, e.g. silicon, gallium arsenide, etc.  Then the rays travel the the backing material, "C," which is normally made of aluminum.  At this point the photons which remain unabsorbed are reflected off of the backing nd ravel at an angle back out of the cell through both "A" and "B."     
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Image:SolarCellLightPath.jpg|Fig 3: is a diagram of how light (the yellow line) enters the solar cell.  It first passes through "A" (the blue region) which is the anti-reflective layer of the cell.  The sunlight then travels through, "B," (the green layer) the material the cell is made of, e.g. silicon, gallium arsenide, etc.  Then the rays travel the the backing material, "C," (the gray region) which is normally made of aluminum.  At this point the photons which remain unabsorbed are reflected off of the backing nd ravel at an angle back out of the cell through both "A" and "B."     
    
Image:2Dsolarcelllayers.jpg|Fig 4: is a two dimensional side view diagram that shows the layers to be applied to a solar or photo voltaic cell.  "A" is a layer of cover glass to protect the underlying layers.  "B" is a layer of anti-reflective layer to prevent photon reflection.  "C" is the top contact grid that allows for the transfer of electricity.  "D" is the layer of the N-type material.  "E" is the layer of P-type material.  NOTE: This creates the needed P-N junction.  "F" finishes the diagram as the back contact for the conduction of electricity through the cell.       
 
Image:2Dsolarcelllayers.jpg|Fig 4: is a two dimensional side view diagram that shows the layers to be applied to a solar or photo voltaic cell.  "A" is a layer of cover glass to protect the underlying layers.  "B" is a layer of anti-reflective layer to prevent photon reflection.  "C" is the top contact grid that allows for the transfer of electricity.  "D" is the layer of the N-type material.  "E" is the layer of P-type material.  NOTE: This creates the needed P-N junction.  "F" finishes the diagram as the back contact for the conduction of electricity through the cell.       

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