Environmental Engineering Reference
In-Depth Information
Figure 7.10
An IPCE curve measured for 3
×
3mm
2
solar cells
after reducing Si doping at the back of the solar cell. Note the drastic
improvementattheIRendshowing855nmGaAscut-offwavelengthinstead
of 740 nm, as shown in Fig. 7.5.
diagram. The situation for this case is now shown in Fig. 7.11,
and the rear section of the solar cell has achieved the required
shapeduetoloweringofSidoping.Therefore,thespectralresponse
has improved at the IR end, showing the right cut-off wavelength
of 855 nm (corresponding to the bandgap of GaAs) instead of
Figure 7.11
An energy band diagram of the improved device with lower
Si doping at the rear of the solar cell.
