Rare earth ions in porous silicon: optical properties

✍ Scribed by Elhouichet, H. ;Oueslati, M.

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 248 KB
• Volume: 204
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.200674402

✦ Synopsis

Abstract

Porous silicon (PS) is doped with rare earth (RE) ions (Er, Eu, Tb) by electrochemical anodisation. The penetration of RE into the PS layer is confirmed by Rutherford Backscattering Spectroscopy (RBS) and by Energy Dispersive X‐ray (EDX) measurements. Efficient visible and infrared emissions were observed at room temperature. The activation temperatures of Eu, Tb and Er in PS are determined from the effect of thermal annealing on the photoluminescence (PL) intensity. From the evolution of the PL intensity versus temperature, it was found that a RE related level defect can be involved on the excitation and emission processes. Pump intensity dependent PL studies revealed that for the electrochemical incorporation, most of the RE ions are localized inside the Si nanocrystallites and not in stochiometric SiO~2~. The optical cross section is close to that of erbium in Si nanocrystallites. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)