Process to manufacture laser structures with lateral confinement at very low threshold current and relevant laser devices so obtained

Claim 1

A process for producing a multilayer structure for emitting coherent luminous radiation comprising a substrate with an electrode formed on one surface and with the following layers, formed in the order recited, on an opposite surface: a first epitaxial layer for optical and electric confinement, an active layer for emitting luminous radiation of a desired wavelength, at least one further layer for optical and electric confinement layer, and an electric contact layer with a second electrode attached thereto, the process including the step of subjecting at least one selected optical and electric confinement layer of said structure to ion implantation, whereby ions of a transition metal are introduced into said selected layer, the active layer of said structure being protected from said ion implantation by a photoresist mask, said implanted ions being activated by thermal treatment, resulting in an increased resistivity in the selected layer of the structure subjected to said ion implantation.