Excimer (ultraviolet) laser-induced quantum well intermixing (UV-Laser-QWI) is an attractive technique for wafer level post-growth processing and fabrication of a variety of monolithically integrated photonic devices. The results of UV-Laser-QWI employed for the fabrication of multibandgap III-V semiconductor wafers have demonstrated the attractive character of this approach although the process accuracy and reproducibility have remained relatively weakly covered in related literature. We report on a systematic investigation of the reproducibility of this process induced with a KrF excimer laser. The influence of both the irradiation with different laser doses and the annealing temperatures on the amplitude of intermixing in InGaAs/InGaAsP/InP quantum well heterostructures has been evaluated based on the photoluminescence measurements. Under optimized conditions, the process allows to blue shift the bandgap of a heterostructure by more than 100 nm with a remarkable 5.3% relative standard deviation.

Radiation from a 193 nm ArF laser was investigated to modify surface properties of InGaAs/InGaAsP quantum well (QW) heterostructures and introduce defects required to enhance intermixing during the annealing process. A top 200 nm thick sacrificial layer of InP served as a reservoir for laser generated defects. The irradiation with up to 90 pulses at 65–150 mJ/cm2 allowed to generate an array of 1.2×1 mm2 sites of QW intermixed material, with bandgap energy blueshifted up to 107 nm. We discuss the mechanism and advantages of this approach for postgrowth wafer level fabrication of multibandgap QW material.

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Superluminescent diodes are used in numerous sensing and testing applications. To achieve the wide emission spectrum and high power required from such devices, we studied an innovative design constituting in several different bandgap energy sections independently electrically pumped. Bandgap modification was obtained by the UV laser quantum well intermixing process.