Fabrication and performance of AlGaAs-GaAs distributed Braggreflector lasers and distributed feedback lasers utilizing first-orderdiffraction gratings formed by a periodic groove structure

摘要

Distributed Bragg reflector (DBR) lasers and distributed feedbackn(DFB) lasers utilizing diffraction grating formed by deeply etchednperiodic grooves were fabricated on an InGaAs-GaAs-strained quantum-wellnactive wafer without using a regrowth process. The first-order groovedngrating that had a 150-nm period and 800-nm depth was etched from thentop surface into the cladding layer on the wafer using electron beamnlithography and a reactive beam etching with a mixture of Br2nand N2 gas. The dependence of optical properties on thenstructure of the grooved grating is discussed in terms of an evaluationnof the coupling coefficient. The fabricated DBR and DFB lasers exhibitnsingle-longitudinal mode oscillation with output powers of 20 mW (DBR)nand 10 mW (DFB) in the measured temperature range betweenn15°C-55°C. The characteristic temperature T0 for thenthreshold current is about 120 K. The slope efficiency is held constantnin the measured temperature range. The performance of these DBR and DFBnlasers demonstrates that the use of the grooved grating providesnwavelength-stabilized lasers with a simple fabrication process