COMPARISON OF FE-DOPED AND P N/P-DOPED INP AS A CURRENT BLOCKING LAYER FOR MONOLITHICALLY INTEGRATED INGAASP/INP LASER-DIODES WITH PASSIVE WAVE-GUIDES/

We have fabricated InGaAsP/InP waveguide integrated laser diodes for t he 1550 nm wavelength region. The passive waveguide was butt-coupled u sing the CH4/H-2 reactive ion etching and metal-organic chemical vapor deposition regrowth techniques. We compared the performances of waveg uide integrated laser diodes with different current blocking layers, i .e., Fe-doped InP and p/n/p-doped InP layers. On the whole, Fe-doped I nP was better than p/n/p-doped InP as a current blocking layer. In par ticular, the reverse leakage current through the butt-coupling region with Fe-InP current blocking layer was approximately 99.9 mu A, while that with p/n/p-InP was 193.7 mu A. We also discussed the leakage curr ent characteristics of waveguide integrated laser diodes with analyses of IdV/dI vs I curves.