We have developed low-pressure metalorganic chemical vapor deposition (LP-MOCVD) technology for the growth of Al-free InxGa1-xAs1-yPy compounds lattice-matched to GaAs substrate for the emission wavelengths of 0.808 and 980 nm. The measured device characteristics such as threshold current density Jth, differential efficiency ηd and characteristic temperature T0, optical loss αi are compared with model calculations. From these comparisons, it is shown that the Al-free InGaAsP systems have almost 100% internal efficiency, having no significant non-radiative recombination recombination that can affect laser operation. It is shown, however, that the lasers, particularly, optical loss and gain spectrum are rather strongly affected by the material alloy composition fluctuation in InGaAsP active region. The laser structure and fabrication were optimized based on these results for highly efficient high temperature high power laser operation. Maximum output powers up to 7 W in CW and 8 W in pulse were obtained from the 0.808-μm InGaAsP/GaAs lasers with the optimized structure. Lifetime testing shows no degradation in laser performance for over 30,000 hours in any of randomly selected several 100 μm-wide uncoated lasers operated at 60°C with 1 W continuous wave output power.
|Original language||English (US)|
|Number of pages||12|
|State||Published - 1998|
ASJC Scopus subject areas
- Materials Science(all)
- Electrical and Electronic Engineering