US5405453-A  B. T. Cavicchi et al, Conference Record, 20th IEEE Photovoltaic Specialists Conference Sep. 1988), pp. 918-923;  J. M. Olson et al, 18th IEEE Photovoltaic Specialists Conf. (1985), pp. 552-555;  J. M. Olson et al, 19th IEEE Photovoltaic Specialists Conf. (1987), pp. 285-288A;  J. M. Olson et al, 20th IEEE Photovoltaic Specialists Conf. (1988), pp. 777-780;  J. M. Olson et al, 21st IEEE Photovoltaic Specialists Conf. (1990), pp. 24-29;  J. M. Olson et al, Appl. Phys. Lett., vol. 56, No. 7, Feb. 1990, p. 623WO9513626-A1  Appl. Phys. Lett., Vol. 56, No. 7, 12/02/1990, J.M. Olson et al., "A 27.3% Efficient Ga0.5In0.5 P/GaAs Tandem Solar Cell", pages 623-624;  Conference Record, 18th IEEE Photovoltaic Specialists Conf., Oct. 1985, J.M. Olson et al, "GaInP2/GaAs: A Current-and Lattice-Matched Tandem Cell with a High Theoretical Efficiency", Pages 552-555;  Conference Record, 19th IEEE Photovoltaic Specialists Conf., May 1987, J. M. Olson et al, "GaInP2/GaAs Monolithic Tandem Solar Cells" pages 285-288A;  Conference Record, 20th IEEE Photovoltaic Specialists Conf., Sept. 1988, B.T. Cavicchi et al "GaAs on Ge Cell and Panel Technology For Advanced Space Flight Application", pages 918-923;  Conference Record, 20th IEEE Photovoltaic Specialists Conf., Sept. 1988, J.M. Olson et al, "A 21.8% GaInP2/GaAs Tandem Solar Cell", pages 777-780;  Conference Record, 21St IEEE Photovoltaic Specialists Conf., May 1990, J.M. Olson et al, "Recent Advances In High Efficiency GaIn P2/GaAs Tandem Solar Cells", pages 24-29;  APPL. PHYS. LETT., Vol. 56, No. 7, 12 February 1990, J.M. OLSON et al., "A 27.3% Efficient Gao.5In0.5P/GaAs Tandem Solar Cell", pages 623-624.;  CONFERENCE RECORD, 18TH IEEE PHOTOVOLTAIC SPECIALISTS CONF., Oct. 1985, J.M. OLSON et al., "GaInP2/GaAs: A Current-and Lattice-Matched Tandem Cell With a High Theoretical Efficiency", pages 552-555.;  CONFERENCE RECORD, 19TH IEEE PHOTOVOLTAIC SPECIALISTS CONF., May 1987, J.M. OLSON et al., "GaInP2/GaAs Monolithic Tandem Solar Cells", pages 285-288A.;  CONFERENCE RECORD, 20TH IEEE PHOTOVOLTAIC SPECIALISTS CONF., Sept. 1988, B.T. CAVICCHI et al., "GaAs on Ge Cell and Panel Technology for Advanced Space Flight Application", pages 918-923.;  CONFERENCE RECORD, 20TH IEEE PHOTOVOLTAIC SPECIALISTS CONF., Sept. 1988, J.M. OLSON et al., "A 21.8% GaInP2/GaAs Tandem Solar Cell", pages 777-780.;  CONFERENCE RECORD, 21ST IEEE PHOTOVOLTAIC SPECIALISTS CONF., May 1990, J.M. OLSON et al., "Recent Advances in High Efficiency GaInP2/GaAs Tandem Solar Cells", pages 24-29.