WO9948157-A1  See also references of EP 0984494A1EP984494-A1  OKADA Y ET AL: "GROWTH OF GAAS AND ALGAAS ON SI SUBSTRATES BY ATOMIC HYDROGEN- ASSISTED MBE(H-MBE) FOR SOLAR CELL APPLICATIONS" WORLD CONFERENCE ON PHOTOVOLTAIC ENERGY,US,NEW YORK, IEEE, vol. CONF. 1, 5 December 1994 (1994-12-05), pages 1701-1704, XP000680140 ISBN: 0-7803-1460-3;  PATENT ABSTRACTS OF JAPAN vol. 008, no. 107 (E-245), 19 May 1984 (1984-05-19) & JP 59 023572 A (MATSUSHITA DENKO KK), 7 February 1984 (1984-02-07);  PATENT ABSTRACTS OF JAPAN vol. 008, no. 268 (E-283), 7 December 1984 (1984-12-07) & JP 59 138386 A (NIPPON DENSHIN DENWA KOSHA), 8 August 1984 (1984-08-08);  See also references of WO 9948157A1;  VERNON S M ET AL: "HETEROEPITAXIAL (AL)GAAS STRUCTURES ON GE AND SI FOR ADVANCED HIGH-EFFICIENCY SOLAR CELLS" PHOTOVOLTAIC SPECIALISTS CONFERENCE,US,NEW YORK, IEEE, vol. CONF. 17, 1 May 1984 (1984-05-01), pages 434-439, XP000013573;  PATENT ABSTRACTS OF JAPAN vol. 008, no. 268 (E-283), 7 December 1984 (1984-12-07)&JP 59 138386 A (NIPPON DENSHIN DENWA KOSHA), 8 August 1984 (1984-08-08);  PATENT ABSTRACTS OF JAPAN vol. 008, no. 107 (E-245), 19 May 1984 (1984-05-19)&JP 59 023572 A (MATSUSHITA DENKO KK), 7 February 1984 (1984-02-07)EP984494-B1  OKADA Y ET AL: "GROWTH OF GAAS AND ALGAAS ON SI SUBSTRATES BY ATOMIC HYDROGEN- ASSISTED MBE(H-MBE) FOR SOLAR CELL APPLICATIONS" WORLD CONFERENCE ON PHOTOVOLTAIC ENERGY,US,NEW YORK, IEEE, vol. CONF. 1, 5 December 1994 (1994-12-05), pages 1701-1704, XP000680140 ISBN: 0-7803-1460-3;  PATENT ABSTRACTS OF JAPAN vol. 008, no. 107 (E-245), 19 May 1984 (1984-05-19) & JP 59 023572 A (MATSUSHITA DENKO KK), 7 February 1984 (1984-02-07);  PATENT ABSTRACTS OF JAPAN vol. 008, no. 268 (E-283), 7 December 1984 (1984-12-07) & JP 59 138386 A (NIPPON DENSHIN DENWA KOSHA), 8 August 1984 (1984-08-08);  VERNON S M ET AL: "HETEROEPITAXIAL (AL)GAAS STRUCTURES ON GE AND SI FOR ADVANCED HIGH-EFFICIENCY SOLAR CELLS" PHOTOVOLTAIC SPECIALISTS CONFERENCE,US,NEW YORK, IEEE, vol. CONF. 17, 1 May 1984 (1984-05-01), pages 434-439, XP000013573