<title>Quantitative spectral analysis in semiconductor laser reliability</title>

Abstract

Quantitative spectral analysis has been developed as an analytic tool for the identification and characterization of defects within the cavities of multilongitudinal mode semiconductor lasers. Unstressed lasers whose spectra suggest the presence of internal, manufacturing-related defects have failed at lower values of electrostatic discharge (ESD) stress than devices that are free of such defects. Lasers that have been selected with spectral analysis tend to fail only at the facets during ESD stress, suggesting that surface recombination and the associated optical absorption limit the stress performance. When the surface recombination velocity at the facets is reduced by passivation in aqueous solutions of ammonium sulfide, the laser failure voltage increases by more than a factor of 5 relative to unpassivated devices. The results of spectral analysis are compared with those of more conventional techniques, such as electroluminescence and low coherence reflectometry. We conclude by presenting recent results from spectral analysis during temperature cycling stress of low cost laser packages developed for fiber in the loop applications.