Implant Depth Influence on InGaAsP/InP Double Quantum Well Intermixing Induced by Phosphorus Ion Implantation

We investigate quantum well intermixing of a double-quantum-well structure caused by phosphorus ion implantation by means of photoluminescence (PL). The ion implantation is performed at the energy of 120keV with the dose ranging from 1×10¹¹ to 1×10¹⁴/cm². The rapid thermal annealing is performed at the temperature of 700°C for 30s under pure nitrogen protection. The PL measurement shows that the band gap blueshift is influenced by the depth of ion implantation. The blueshift of the upper well which is closer to the implanted vacancies is enhanced with the ion dose faster than that from a lower well under the lower dose implantation (<5×10¹¹/cm²). When the ion dose is over 10¹²/cm², the band gap blueshift from both the wells increases with the ion dose and finally the two peaks combine together as one peak, indicating that the ion implantation results in a total intermixing of both the quantum wells.