Low Threshold GaInAsP/InP Distributed Feedback Lasers with Periodic Wire Active Regions Fabricated by CH 4 /H 2 Reactive Ion Etching

Low damage GaInAsP/InP narrow wire structures with vertical mesa shape were realized by CH 4 /H 2 -reactive ion etching followed by a slight wet chemical etching and an embedding growth by organo-metallic vapor phase epitaxy. By using this fabrication process, a threshold current density as low as 330 A/cm 2 (66 A/cm 2 /well, @ L =860 µm) was obtained for 1.55 µm wavelength five-quantum-well distributed feedback (DFB) laser consisting of periodic wire active regions. To our knowledge this is the lowest value reported for 1.55 µm GaInAsP/InP DFB lasers fabricated by the dry etching process.