Patent ID: 6506622
Filing Date: 2003-01-14
Classification: H01L,Y02E,Y02P

Abstract:
A method of manufacturing a photovoltaic device comprising:depositing joined semiconductor layers on a substrate; and forming concavities and convexities on the surface of the substrate and the surface of the joined semiconductor layers such that the substrate has a substantially planar surface with (a) a highest point, and (b) a lowest point, such that (i) a substrate center value that is the mean elevation between said highest point and said lowest point can be determined, (ii) a total, TAsub-above, of projected areas of regions of the substrate surface that lie at or above the substrate center value is determined, each said projected area being the cross-sectional area of a columnar projection extending perpendicular from the region, and (iii) a total, TAsub-entire, of the projected area of the entire substrate surface is determined; â€ƒand the joined semiconductor layers have a substantially planar surface with (c) a highest point, and (d) a lowest point, such that (iv) a semiconductor center value that is the mean elevation between said highest point and said lowest point is determined, (v) a total, TAsemi-above, of projected areas of regions of the surface of the joined semiconductor layers that lie at or above the semiconductor center value is determined, each projected area being the cross-sectional area of a columnar projection extending perpendicular from the region, and (vi) a total, TAsemi-entire, of the projected area of the entire surface of the joined semiconductor layers is determined; and wherein the ratio of TAsemi-above to TAsemi-entire is greater than the ratio of TAsub-above to TAsub-entire.