Quantum well intermixing in GaAs-AlGaAs laser structure using sol-gel SiO2 dielectric cap

摘要

Abstract: Intermixing of quantum confined heterostructures, or quantum well intermixing (QWI), is an attractive alternative to regrowth and overgrowth techniques for realizing photonic and optoelectronic integrated circuits. Impurity free vacancy diffusion using SiO$-2$/ dielectric cap is one of the promising QWI techniques. Silicon dioxide is known to induce outdiffusion of Ga and generate vacancies in GaAs- AlGaAs material during annealing. These vacancies, generated on the group-III sublattice, can be used to promote the diffusion of Al into a buried quantum well (QW) and the diffusion of Ga into the barriers and hence shift the QW band gap to higher energy by partially intermixed the quantum well.!6