GaAs heteroepitaxial growth on Si for solar cells

摘要

Thermal annealing effects on the reduction of dislocation density in GaAs on Si substrates were investigated. The dislocation density in GaAs films grown on Si substrates by metalorganic chamical vapor deposition was reduced byinsituthermal annealing to 2times;106/cm2. We have found that the cooling and heating cycle of the GaAs film is most important factor in reducing the dislocation density in thermal annealing. Solar cells fabricated using GaAs films with 5times;106/cm2etch pit density have 18percnt; conversion efficiency for the active area under AM1.5 simulated illumination.