OPTOELECTRONIC DEVICES BY GAS SOURCE MOLECULAR-BEAM EPITAXY

Different structures for optoelectronic devices have been grown by gas source molecular beam epitaxy. Strained layer multiquantum well structures with quarternary wells exhibit low threshold current density (J(th) = 510 A/cm2) and high T0 value (90 K). A two step growth procedure enables the realization of the vertical structure distributed feedback laser with very good control of the coupling coefficient between laser mode and engraved gratings. Finally, the realization of a buried heterojunction laser is demonstrated in a three-step epitaxial process and a new lift-off procedure avoiding the use of a dielectric mask. Preliminary devices show power emission up to 40 mW with a threshold current I(th) = 60 mA.