Vertical-Cavity Surface-Emitting Laser Diodes Fabricated by In Situ Dry Etching and Molecular Beam Epitaxial Regrowth

We report the first buried active region verticalcavity surface-emitting laser diodes fabricated using in situ dry etching and molecular beam epitaxial regrowth. The laser emission of the etched / regrown devices persist over a greater current range and exhibit maximum output powers larger than air-post lasers. The lasers are anisotropically etched into the lower monolithic distributed Bragg reflector using an electron cyclotron resonance SiCl₄ plasma etch. After transfer in ultra-high vacuum, epitaxial AlGaAs current blocking layers are regrown around the etched mesas. Polycrystalline deposition on the Si0₂ mask is removed by reactive ion etching to allow electrical contact and top surface emission. The etched / regrown laser characteristics demonstrate efficient current confinement and low thermal impedance. The vacuum integrated processing described here offers the prospect of further device performance enhancements and greater functionality.