Design and realization of a buried-heterostructure tunable-twin-guide laser diode with electrical blocking regions

An InGaAsP-InP buried-heterostructure tunable-twin-guide (TTG) laser diode is presented, incorporating epitaxially regrown p-n-p-n current blocking re gions to minimize current leakage around the active region in the ridge, Th e laser design is based on a theoretical model describing the mechanism of current leakage and the influence of electrical blocking regions by a two-d imensional computer simulation. The technological realization of the laser device reveals a way to achieve a self-aligned transverse blocking region a nd a lateral ridge contact in any desired depth by a two-stage epitaxial pr ocess, Completely processed TTG laser diodes with buried blocking regions e xhibit very good high-temperature performance and a wavelength tuning range of around 4.5 nm under forward bias together with a maximum light output o f as much as 25 mW at room temperature.