Rear point contact (locally diffused) solar cells with double collecting p/n junctions are investigated through numerical three-dimensional simulation and comparison with corresponding single junction solar cells. Their illuminated I-V characteristics are simulated and the series resistance of both structures is calculated. Results are presented which show the influence of the additional collecting junction to the cell's series resistance and performance. It is also shown that by biasing both junctions under slightly different voltages, the efficiency of the cell slightly increases. (C) 2002 Elsevier Science B.V. All rights reserved.