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.