Abstract: An edge-emitting optical semiconductor structure has a substrate, an active multiple quantum well (MQW) region formed on the substrate, and a ridge waveguide extending between first and second etched end facets. The first etched end facet is disposed in a first window, while the second etched end facet is disposed in a second window. The first etched end facet extends between a pair of alcoves in the first window, and the second etched end facet extends between a pair of alcoves in the second window. An integrated device in which two such structures are provided has an H-shaped window where the two structures adjoin each other. The structure can be fabricated using a process that involves a first mask to form the ridge waveguide and then a second mask and an etching process to form the windows.