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Solar cells are made of
Silicon
Germanium
Silver
Aluminium
Silicon
Solar cells (photovoltaic cells) are primarily made from semiconductor materials, with crystalline Silicon being the industry standard due to its abundance and bandgap properties ┬╖ These devices convert sunlight directly into electricity via the photovoltaic effect.
Solar cells (photovoltaic cells) are primarily made from semiconductor materials, with crystalline Silicon being the industry standard due to its abundance and bandgap properties ┬╖ These devices convert sunlight directly into electricity via the photovoltaic effect.
E=h╬╜=╬╗hcтАЛ тАФ Energy of incident photons
EgтАЛтЙИ1.1┬аeV тАФ Bandgap energy of Silicon at 300K
When photons with energy E=h╬╜ greater than the semiconductor bandgap energy EgтАЛ strike the Silicon, they excite electrons from the valence band to the conduction band ┬╖ This creates electron-hole pairs, which are separated by the internal electric field of the p-n junction, generating a DC current across the external load.
Silicon is an indirect bandgap semiconductor.
The efficiency of a single-junction silicon cell is limited by the Shockley-Queisser limit.
Doping agents like Phosphorus (n-type) and Boron (p-type) are used to create the p-n junction.
High abundance of silicon in the Earth's crust
Excellent long-term stability and environmental durability
Low energy conversion efficiency for single-junction cells
High-temperature sensitivity reduces voltage output
Residential and industrial solar panels
Spacecraft and satellite power systems
Silicon is preferred over Germanium because Silicon has a more suitable bandgap (1.1┬аeV vs 0.67┬аeV) for solar spectrum harvesting and better thermal stability.
Option B (Germanium) is used in multijunction cells but is too costly for standard panels ┬╖ Option C (Silver) is used for conductive contacts, not the semiconductor body.
A is correct тАФ Silicon is the most widely used semiconductor material for fabricating efficient, stable, and cost-effective photovoltaic cells.
Always remember that while Silicon is standard, the bandgap energy EgтАЛ must be optimal (typically 1.0тАУ1.5 eV) to match the solar spectrum peak; this is why materials like GaAs are also highly efficient.