For a gap of (gallium arsenide)

PHYSICS · Multi-part · Fermi University Physics · Condensed Matter, Materials & Soft Matter · Semiconductor physics and devices · Semiconductor physics and devices

Condensed Matter Physics, Ch The junction: diodes, transistors, lamps and solar cells

Problem

For a gap of

1.42\,\mathrm{eV}

(gallium arsenide), worked out the same way the chapter worked out silicon's, the sun's spectrum gives a below-gap loss of

36\ \%

and a thermalisation loss of

23\ \%

. ((a)) Find the two-loss estimate, the largest fraction of the sun's power such a cell could use before its voltage and fill factor are counted. ((b)) A well-made gallium arsenide cell measures

V_{\rm oc}=1.05\ \mathrm{V}

and a fill factor of

0.86

. Using the same method as the chapter's Kaneka calculation, estimate this cell's overall efficiency.

Browse the problem library