Wafer level optoelectronic testing for DFB laser diodes

We have developed a testing methodology for DFB lasers and the Electro-Absorption Modulated Laser (EML) in particular which circumvents some of the previously assumed barriers to facetless wafer level testing of edge emitting laser devices. These new wafer level tests are providing manufacturing with a variety of device performance parameters on both the laser and the modulator while embedded in the wafer. While the wafer level parameters are not expected to be identical to their final facet coated CHIP values they show excellent correlation between several important WAFER and CHIP parameters. This paper will describe how we measure facetless, in-wafer laser and modulator characteristics on our wafers and review the correlation and successes we have had during implementation in production.