Light emitting diodes on silicon substrates: preliminary results
Résumé
III-V quantum wells (QW) superlattices have been grown by molecular beam epitaxy on GaP substrates for photonics applications on silicon. We first present room temperature photoluminescence (PL) results for GaAsP/GaP QWs. A detailed analysis of low temperature PL experiments is then performed. QW contribution is pointed out, and the structuration of the QW emission is attributed to LA phonon replica. A comparison with electronic bandstructure is performed, and a discussion is proposed on the nature of the observed transition (direct or indirect). Finally, it is shown that these QWs can be used as active zone in light emitters on silicon. Growth of good quality GaP epilayers on silicon is also presented. The crystalline quality of the deposited GaP near the GaP/Si interface is studied by Raman spectroscopy.