1ST ORDER DISTRIBUTED FEEDBACK GRATINGS (92.5-105 NM PERIOD) FOR GAINP/ALGAINP LASERS EMITTING IN THE VISIBLE RANGE

The fabrication of first order gratings for distributed feedback (DFB) GaInP/AlGaInP laser structures with periods in the range of 100 nm will be reported. The laser structures were pumped optically and show single mode emission at 639 and 651 nm with coupling coefficients of 151 cm-1. Due to the principally nonexisting radiation mode loss first order DFB lasers will show lower thresholds than the yet demonstrated third order DFB lasers with three times coarser grating periods. The gratings fabricated by e-beam lithography and dry etching techniques show strong feedback and moderate damaging of the waveguide properties.