A novel method to improve VCSELs oxide-confined aperture uniformity using selective As+-implanted underlying layer

We report the utilization of an selective As+-implanted underlying layer and regrowth method to enhance and control the wet thermal oxidation rate for 850 nm oxide-confined VCSEL. The oxidation rate of the As+-implanted device showed a four-fold increase over the non-implanted one at the As+ dosage of 1 × 1016 cm−3 and the oxidation temperature of 400 °C. The 50 side-by-side As+-implanted oxide-confined VCSELs fabricated using the method achieved very uniform performance with a deviation in threshold current of ΔIth ∼ 0.2 mA and slope-efficiency of ΔS.E. ∼ 3%. Finally, we accumulated life test data for oxide-confined VCSELs with As+-implanted underlying layer up to 1000 h at 80 oC/15 mA.