Patent ID: 7355114

Claim:
A solar cell having a light-receiving surface which is configured by a first main surface of a semiconductor single crystal substrate having a plurality of nearly-parallel grooves formed thereon, each groove having an electrode for extracting output disposed on the inner side face thereof only on one side in the width-wise direction thereof, wherein a minimum depth h of each groove satisfies the relation below: h â‰§W 1 tanÎ¸ where, Î¸ represents an angle between a line which connects the lower end, along the thickness-wise direction of the semiconductor single crystal substrate, of the electrode formed in one groove having the largest depth among all grooves as viewed along an arbitrary section normal to the longitudinal direction of the individual grooves, and the upper end of the inner side face of the same groove having no electrode formed thereon, and a reference line normal to the thickness-wise direction, and W i represents width of the groove defined by a distance between both opening edges of the groove, and wherein the semiconductor single crystal substrate has thickness decreasing from a first side of a first main surface to a second side opposed to the first side; and wherein the plurality of grooves have a depth distribution of being deepest at a thickest position of the semiconductor single crystal substrate, and a gradually becoming shallower towards a thinnest position of the substrate.