High temperature operation of GaInAsN laserdiodes in the 1.3 /spl mu/m regime

1.3 /spl mu/m semiconductor lasers operating over a wide temperature range without thermoelectric coolers are very important light sources for optical access and optical interconnection systems. The performance of currently used InGaAsP based lasers, especially at high temperatures, is very limited due to a small conduction-band offset (Temkin et al., 1993), making uncooled devices unpractical. Much higher operating temperatures have been obtained with AlGaInAs laser diodes employing electron stopper layers (Takemasa et al., 1998), but the results presented here show that even those seem within reach in the near future for the GaInAsN material system (Reinhardt et al., 2000). We have fabricated GaInAsN double quantum well (DQW) ridge waveguide laser diodes showing record high temperature operation up to 175/spl deg/C. The SCH laser structure was grown on a [001] oriented n-GaAs substrate by solid source MBE. A radio frequency (RF) plasma source was used for supply of active nitrogen from ultrapure N/sub 2/ gas. The active region, consisting of two 7 nm GaIn/sub 0.38/AsN/sub 0.14/ quantum wells separated by 15 nm GaAs barriers, is symmetrically embedded in a 300 nm thick undoped GaAs waveguide. The n- and p-type cladding layers consist of 1.5 /spl mu/m Al/sub 0.34/Ga/sub 0.66/As doped with Si and Be to about 1/spl times/10/sup 18/ cm/sup 3/. A 140 nm p/sup +/ doped GaAs cap serves as a contact layer. The structures were processed by photolithography and reactive ion-etching into ridge waveguide lasers with widths of 6 /spl mu/m.