Fabrication of Submicron Gratings for 1.5 μm InGaAsP / InP Distributed Feedback Lasers by Reactive Ion Etching Using C 2 H 6 / H 2

Etching conditions for submicron period gratings on InP substrates by reactive ion etching using a C 2 H 6 /H 2 mixture have been systematically investigated. Etching rates and shapes of grooves in samoles are assessed after being etched under various gas pressure conditions, C 2 H 6 /H 2 flow ratios, and RF power densities. The pressure affects the angle of the etched side wall