.gainassb / Algaassb Semiconductor Laser Device Technology And Characterization Techniques Study

The processing and characterization techniques of GaInAsSb/AlGaAsSbmultiple quantum well (MQW) lasers operating at wavelength 2μm are investigated.computer based semiconductor laser parameter analyzing system has been constructedfor the characterization of this lasers under pulse driving conditions. The chemicaletchant used for the processing of those lasers has been studied. The main results areas follows as:A computer based laser parameter analyzing system controlled by GeneralProgrammable Interface Bus (GPIB) has been designed and constructed, which issuitable for the characterization of the laser chips under both pulse and continuosworking (CW) drive conditions. The pulse drive ability of this system is great than 1Awith pulse width less than l00ns.A new etchant consists of hydrofluoric acid, peroxide and tartaric acid for thechemical etching of GaSb/AlGaAsSb materials has been studied. This etchant hasstable etching rate for both GaSb and AlGaAsSb compound materials, under moderatesolution composition quite low etching rate could be obtained, which are useful forthe fabrication of GaSb/AlGaAsSb devices.Ridge-waveguide lasers were fabricated by using molecular beam epitaxy(MBE) grown GaInAsSb/AlGaAsSb with three quantum-wells broadened-waveguideseparate confinemeat heterostructure material. At room-temperature quasi-continuousoperation, the lasers show threshold current as low as 90 mA, with maximum lasingtemperature great than 80℃.The characters of those lasers under pulse operation have been studied. I-Pcharacteristics at room temperature has been demonstrated and show that the heatingeffect, as well as non-radiative recombination in the active region still dominate themain reason of the laser degradation under higher temperature, which prevent thelasing of the device under CW driving.The emitting spectrum of the GaInAsSb/AlGaAsSb laser was studied byusing FTIR spectrometer. A red-Shift of the lasing spectrum with the increase of thedriving current was observed, the reasons were also discussed.