Role of antireflection coating in microgrooved silicon solar cells

The role of AR coatings in microgrooved solar cells having different slat angles has been studied in detail deriving the expression of the reflection coefficient for various slat angles for unencapsulated and encapsulated cells. The role of flats of texturized surfaces have also been studied. It is shown that there is little influence of the AR coating when the slat angle is less than 55 degrees, while the improvement of the short-circuit current may be as high as 22% on a slat angle of 70.5 degrees, It is observed that encapsulated cells having small groove angles (< 55 degrees) have greater efficiencies than the cells having groove angles in the range of 90 degrees to 120 degrees, but exhibit larger variation in efficiency with changes in the flat-top area coverage. The optimum thickness for single layer AR coated (ZnS) encapsulated cells and also for SiO2 coated unencapsulated cells is 1250 Angstrom.