Patent ID: 7217883

Claim:
A method of manufacturing a solar cell, which method comprises providing a silicon wafer having a light-receiving front side and a backside with a basic doping, and providing the silicon wafer at its backside with an interdigital semiconductor pattern, wherein providing the interdigital semiconductor pattern comprises the steps of: (a) applying to the backside a doping paste containing a first dopant to obtain a pattern of at least one area covered with doping paste; (b) drying the doping paste; (c) producing a pattern of at least one first diffusion zone having a first doping by forcing at elevated temperature in a free oxygen-containing atmosphere the first dopant to diffuse into the silicon wafer, and simultaneously producing a silicon oxide layer; (d) etching part of the silicon oxide layer by applying a first etching agent in areas between the first diffusion zones, and removing the first etching agent and the etched silicon oxide layer to obtain a pattern of silicon oxide rims; (e) etching part of the silicon wafer by applying a second etching agent between the silicon oxide rims, and removing the second etching agent and the etched silicon to obtain a pattern of at least one groove; (f) producing a second diffusion zone having a second doping on the sides of each of the at least one groove, wherein the second doping differs from the first doping; and (g) removing the doping paste and the remainder of the silicon oxide layer to obtain the interdigital semiconductor pattern.