Semiconductor Devices And Methods

A semiconductor laser device includes, in a disclosed embodiment: a semiconductor active region disposed between upper and lower confining regions of opposite type semiconductor material; reflective facets at opposing edges of the active and confining regions; at least one of the confining regions including a layer of relatively high aluminum fraction aluminum-bearing III-V material between layers of relatively low aluminum fraction aluminum bearing III-V material, the layer of relatively high aluminum fraction material having, at its edges and adjacent the facets, spikes of native oxide of aluminum; and electrodes for applying electric potential across the upper and lower confining regions.