AVS 52nd International Symposium
    Electronic Materials and Processing Thursday Sessions
       Session EM2-ThM

Paper EM2-ThM5
Implantation-Defect-Mediated Intermixing of InAs/InP Quantum Dot Layers

Thursday, November 3, 2005, 9:40 am, Room 310

Session: Heteroepitaxy and Low-Dimensional Structures
Presenter: C. Dion, École Polytechnique de Montréal, Canada
Authors: C. Dion, École Polytechnique de Montréal, Canada
S. Raymond, National Research Council of Canada
G. Ortner, National Research Council of Canada
P.J. Poole, National Research Council of Canada
F. Schiettekatte, Université de Montréal, Canada
M. Chicoine, Université de Montréal, Canada
P. Desjardins, École Polytechnique de Montréal, Canada
Correspondent: Click to Email
The reduced dimensionality provided by quantum dots (QDs), which leads to atom-like discrete energy levels and @delta@-function-like density of states, offers possibilities for considerable improvements in optoelectronic device applications. However, the use of these nanostructures relies on achieving precise tunability of QDs luminescence emission through QDs size and composition. Since InAs/InP QDs growth is complicated by the rapid exchange of group V species at the InAs/InP interfaces, a post-growth method to fine tune the electronic properties of this particular system is of great relevance. We have investigated the effect of post-growth P implantation followed by rapid thermal annealing on the low-temperature photoluminescence (PL) spectra of self-assembled InAs/InP(001) QDs grown by chemical beam epitaxy (CBE) and metal-organic vapor phase epitaxy (MOVPE). In untreated samples, threshold temperature for intermixing was found to be 725 °C with blueshifts of the PL peaks of up to 90 meV after RTA at 800 °C for 210 s, while preserving emission bandwidth. In order to obtain larger blueshifts, we studied the effect of introducing point defects into InP cap layers by implanting P at energies sufficiently low to insure that the InAs QDs were not damaged. Implantation with fluence as low as 10@super 12@ P/cm@super 2@ followed by annealing at 500 °C were sufficient to induce a 275 meV blueshift. These observations give important insights into the role of defects generated in InP-based structures on the As/P intermixing and reinforce the applicability of ion implantation for the fabrication of monolithically integrated devices. Implantation-defect-mediated intermixing for wavelength tuning of InAs/InP QDs-based laser structures was investigated.