Light-trapping structures for multi-quantum well solar cells

Multi-quantum well (MQW) cells extend the absorption of bulk gallium arsenide cells to longer wavelengths, increasing short-circuit current and have been shown to exhibit a similar dark current to their p-i-n control cells. To complement the recent addition of rear surface mirrors, similar techniques to those employed in silicon cells may be used. These include the texturing of the front surface and use of diffraction gratings. Both are considered here and their effect upon the short-circuit current (J/sub sc/) calculated. Such techniques could allow the number of quantum wells to be reduced, improving the dark current of the cell.