Buried refractive microlenses formed by selective oxidation of AlGaAs

Abstract
The authors demonstrate a novel method of fabricating buried refractive microlenses formed by selective oxidation of AlGaAs epitaxial layers on a GaAs substrate. By appropriate tailoring of the Al mole fraction in the vertical direction, a lens-shaped oxidation shape was achieved. Performance of the microlenses formed in this way was experimentally evaluated at 980 nm, and modelled theoretically.