Atsuo Tsunoda

Reliable red-emitting laser diodes grown by solid source molecular beam epitaxy

Abstract We achieved over 1000 h stable continuous wave (CW) operation of AlGaInP laser diodes (LDs) with output power of 30 mW at 50°C by using all solid source molecular beam epitaxy (MBE). In this paper the essential points for reliability are described. If sufficient outgassing of source materials was performed, secondary ion mass spectrometry (SIMS) signals of hydrogen and oxygen from the as-grown layers became small. Reduction of these impurities dramatically increased photoluminescence (PL) intensity and decreased the threshold currents of LDs. Growth condition dependence of device performance was also investigated. Whilst the acceptable ranges of V/III ratio and phosphorus cracking temperature needed to obtain reliable operation were extensive, the suitable growth temperature range was limited.

Visible Laser Diodes Grown by Molecular Beam Epitaxy

High-quality AlGaInP lavers lattice-matched to a GaAs substrate have successfully been grown by solid source MBE with a dimeric phosphorus beam. The bulk crystal quality and the abruptness of heterointerfaces were studided by measuring a photoluminescence spectrum. Net acceptor concentration in Be doped AlInP reaches saturation above -1×1018 cm-3. A 10-μm wide stripe-geometry GaInP/AlInP laser diode is capable of stable CW operation at room temperature. The maximum output power of 12 mW was achieved.