Semiconductor laser

Abstract

A semi-conductor laser comprising a crystal having a sequence of layers forming a heterostructure diode and which includes a laser active zone interposed between a pair of semiconductor layers. Each of these semi-conductor layers has a band gap which is greater than that of the layers within the laser active zone. The laser active zone includes a first semiconductor layer having a given band gap, and at least second and third semiconductor layers each having a band gap which is greater than that of the first layer. The first layer is contiguous with and interposed between semiconductor layers each having a band gap which is greater than that of said first layer and forms a pn-junction with one of those contiguous layers. A strip-shaped region of a uniform conductivity type diffused from the surface of the crystal penetrates into at least one layer of the laser active zone but does not penetrate into the first layer.

Dependencies are inferred from the claim text.