Improved luminescence from InGaAsP/InP MQW active regions using a wafer fused superlattice barrier

This paper investigates the luminescence properties of InP/InGaAsP multiple quantum well (MQW) laser active regions. Room temperature photoluminescence studies were performed on doped and undoped active regions before fusion, after fusion, after thermal cycling, and after rapid thermal annealing. It is shown that quantum well luminescence intensity degrades considerably after wafer fusion. The introduction of a superlattice defect blocking layer at the fusing surface of the MQW active region not only prevents degradation of the luminescence, but actually improves the luminescence of the MQW active region through the fusion process by a factor of four.