A new high volume MOVPE reactor for III-V solar cells

A new MOVPE reactor is described which allows cost effective manufacturing of GaAs/Ge solar cells. The reactor, which has a batch size in excess of 0.25 m/sup 2/, was co-developed by Spectrolab and Aixtron Semiconductor Technologies over a two year time frame and was installed at Spectrolab in late 1993. Manufacturing readiness data on large area single junction GaAs/Ge solar cells show that the thickness and compositional uniformity of GaAs and AlGaAs layers grown in the system are /spl plusmn/3%, and /spl plusmn/1.5% respectively. There is excellent correlation between empirical data and simulations performed during the initial reactor development phase. The minimum average AM0, 28/spl deg/C efficiencies of 7 mil and 5.5 mil single junction GaAs/Ge solar cells, manufactured from material grown on this system, are over 18.5%.