Abstract: A process for manufacturing semiconductor devices including a plurality of semiconductor layers arranged over a substrate, the semiconductor layers including at least one active layer. The process comprises the steps of vertically etching the plurality of semiconductor layers, the vertical etching including reactive ion etching of the semiconductor layers, and a subsequent regrowth of the laser structure in a regrowth reactor. The process includes the step of in-situ etching the laser structure in the regrowth reactor after the reactive ion-etching step. The process is effective in obtaining smooth planar and lateral surfaces for the regrowth step.