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The photonics industry has developed specialized process technology to fabricate optoelectronic devices in InP based material systems. We define features narrower than 100-nm to fabricate gratings in distributed- feedback lasers. There are waveguides many tens of microns across with dimensional tolerances near ± 0.1 ,um. We often require several stages of epitaxial processing, typically metal organic chemical vapour deposition (MOCVD) with micro-fabrication steps in between. Preparation of interfaces is often crucial, particularly prior to MOCVD and diffusion processes. We often deposit thin films on etched or cleaved facets to provide passivation or to adjust reflectivity. The films must endure harsh aging at high temperature under intense illumination. These and many other processes were developed during the pioneer days on wafer pieces using equipment that lagged far behind the sophistication of the Silicon industry. More than a decade ago Nortel Networks was among the first companies to transfer the processes to a 2- inch wafer standard. Nortel Networks has recently made a substantial capital investment to put our InP processes on 3-inch wafers with more modern equipment to further improve process control, cycle time, and yield. This presentation is a quick survey of some of the successes and challenges we encountered.
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