Photoluminescence enhancement by inductively coupled argon plasma exposure for quantum-well intermixing

Abstract

The exposure of InGaAs/InGaAsP quantum-well (QW) structures to argon (Ar) plasma in an inductively coupled system has been studied. An increase in photoluminescence (PL) intensity without PL peak shift was observed for 5-min Ar plasma exposure compared to the as-grown sample. The exposure creates point defects, and upon rapid thermal annealing produces intermixing between barriers and QWs, resulting in the blueshift of QWs. A selective intermixing using a 200-nm-thick of SiO2 layer as an intermixing mask exhibited a differential band-gap blueshift of 86 nm, with a differential linewidth broadening of 0.3 nm between masked and unmasked section. The improvement of PL intensity in combination with selective intermixing process can pave the way for high-quality hybrid photonic and optoelectronic integrated circuits.