Reactive ion etching of InP with Br2-containing gases to produce smooth, vertical walls: Fabrication of etched-faceted lasers

Abstract
We describe the reactive ion etching of InP using a mixture of Br2 and either N2 or Ar. We report the first fabrication of straight vertical walls in InP at a very fast etching rate of 2 μm/min. By using a mixture of Br2 and Ar and raising the substrate temperature, smooth walls are obtained. To demonstrate that the etched walls can be used as laser mirrors, we fabricated etched‐faceted lasers with threshold currents of 19.0 mA for a laser with one etched and one cleaved facet and 26.6 mA for a laser with two etched facets.