High-throughput zone-melting recrystallization for crystalline silicon thin-film solar cells

摘要: Abstract Crystalline silicon thin-film solar cells which shall exceed a conversion efficiency of 15% require coarse-grained layer at least 5 μm thickness as an absorber layer, with minority carrier diffusion length and grain diameter twice the thickness. At Fraunhofer ISE, we use zone-melting recrystallization to recrystallize grown by chemical vapor deposition on high-temperature stable substrates. Our main focus is development tools processes for achieving layers sufficient electrical quality high throughput low cost. A processor in-line zone melting 400-mm-wide samples was developed, has gas curtain load locks thus offers theoretical maximum approx. 10 m 2 /h velocity 500 mm/min. Zone-melting experiments varying showed that crystal can be maintained even velocities up 350 mm/min.