Solar Cells and Integration of Nanotechnology

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Solar Cells and Integration of Nanotechnology

• Organic/Inorganic solar cells
• Silicon solar cells are most common and efficient
  right now.
• Reflection of incoming light is a big natural
  limitation for efficiency.

Evergreen Solar, Inc. Marlboro, MA
Konarka
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Typical P-N Junction Silicon Solar Cell Structure
Sunlight
Top side metallization grid
0.5 µm
n emitter
Average phosphorus1018cm-3
p base
100-300 µm
Boron1016cm-3
Optional p back surface diffusion
Back side metallization
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Pattern Transfer by Etching (Tunable
Anti-Reflective Coating)
J. Vac. Sci. Technol. B 20.6., Nov. Dec 2002
Can work as an anti-reflective coating!
UMASS
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Single Cell vs. Cut Cells
Vout3 Volts
Vout0.5 Volts
Single Cell
Cut cells connected in series
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Electrical Measurements
Voc
Vmax
Dist. I V I.V



Maximum power rectangle
Imax
Isc