Controlled Oxide Vertical-Cavity Surface-Emitting Lasers with Lateral Oxidation Barriers

Period of Performance: 04/09/1997 - 09/02/1999


Phase 2 SBIR

Recipient Firm

Picolight, Inc.
4622 Sunshine Canyon Dr.
Boulder, CO 80302
Principal Investigator

Research Topics


Based on the Phase I experimental demonstration of feasibility, the proposed Phase II program will produce manufacturable and reliable oxide vertical-cavity surface-emitting lasers (VCSELs). Although oxide VCSELs have spectacular performances (50% wallplug efficiency, etc.) their manufacturability is questionable since the oxidation process forming the current aperture is highly sensitive to temperature, time and aluminum concentration. Furthermore, the oxidation processes may continue after fabrication, albeit at a slower rate, and degrade reliability. In contrast, the proposed VCSELs would have their current apertures defined by photolithography. Since the apertures comprise lateral oxidation barriers, the oxidation process is greatly suppressed within the apertures, thereby enhancing reliability. Three approaches to photolithographic control of oxidation are now identified, compared to the original one described in the Phase I proposal. One approach has been demonstrated. Initial investigations are also underway for a second approach in the Phase I program. The Phase II program will fabricate VCSELs early on in order to identify potential problems with either approach. The remainder of the program will be fabrication-intensive, alternately producing test structures and test VCSELs, culminating with the identification and verification of the preferred process.