To face up the increase in their application fields, laser emitters, including VCSELs, are moving rapidly towards greater integration capabilities, as well as diversified functionalities. Within this framework, we have focused our effort on the improvement and physical understanding of the wet GaAlAs oxidation technology. This process, known as AlOx, is nowadays largely used to fabricate high-performance single-mode VCSELs through the resulting electro-optical lateral confinement that it offers. We have investigated how to finely control the process and exploit it for 2-dimensional structuration of the refractive index, and the electrical confinement. The kinetics of oxidation was thoroughly investigated in Al-rich AlGaAs digital alloys. Moreover, an original real-time in situ control of the oxidation front was proposed, leading to the development of a dedicated optimized oven that allows controlled size AlOx apertures to be achieved. The actual limit of the process is related to the lateral oxidation which hinders engineering capabilities. To overcome this, a derived oxidation technique applicable from the surface (through lithography) of a GaAlAs buried layer was proposed and demonstrated.