EFFICIENCY IMPROVEMENT IN POLYCRYSTALLINE SILICON SOLAR-CELLS AND DEVELOPMENT OF BASIC TECHNOLOGIES FOR LARGE-SCALE MASS-PRODUCTION

For efficiency improvement in polycrystalline silicon solar cells, red uction of surface reflectance and formation of shallow junctions were investigated. A record high conversion efficiency of 17.2 % was achiev ed for a 10 x 10 cm(2) polycrystalline silicon solar cell. For the red uction of solar cell cost, it is necessary to develop basic technologi es for large scale mass production based on the technologies for high conversion efficiency. Simultaneous firing of both front side and back side printed electrodes was investigated. Same cell performances were obtained through the simultaneous firing process which displaced the former separate firing process. Even in the case that belt speed was 2 000 mm/min, almost the same cell performances were obtained. As a resu lt, the process time of electrode formation was shortened remarkably.