High-speed 1.55μm GaInAsP/InP DFB laser with simple mesa structure

A new mesa structure has been developed for high-speed 1.55μm GaInAsP/InP DFB lasers. This structure was easily fabricated using Ar ion beam etching on broad-areacontacted BH wafers. Laser parasitics were reduced by making the carrier concentration of the n-InP burying layer as low as 5 × 1016cm−3. A 3dB bandwidth of 7GHz was achieved.