Precise control of the blue-shift of the wavelength in InGaAs-InGaAsP multiple quantum wells using a sputtered SiO2 technique

Use of the sputtered SiO₂ technique for quantum well intermixing, a post-growth technique which modifies the quantum well profile, to introduce a blue-shift of the optical absorption edge, makes it possible to integrate the passive and active components monolithically and therefore allow extensive photonic integration which is cost effective and flexible. Although the different bandgaps can be implemented by several sputter-annealing cycles, it is tedious and less reliable. In this paper, we report a new technique to achieve the different bandgaps in a single stage sputtering-annealing step. The technique is simple, reliable, and more importantly, the tuning of the wavelength is precise