PHOTOLUMINESCENCE DEPENDENCE ON TEMPERATURE:
ORIGIN OF EMISSION FROM AGED POROUS SILICON
A. Moadhen, H. Elhouichet*, M.Oueslati
Laboratoire de physique de la matière condensée - Equipe de Spectroscopie Raman, Faculté des Sciences de Tunis, Département de physique, 1060 le Belvédère, Tunis - Tunisie
* Corresponding author. E-mail : email@example.com
Received : 09 May 2002; revised version accepted : 20 December 2002
The temperature dependence of photoluminescence (PL) of aged porous silicon (PS) has been investigated. The origin of multipeaks and bands in the PL spectrum is studied. We show that red PL is attributed to quantum confinement in nc-Si crystallites. The bleu PL is relatively intense at low temperatures. Its presence is attributed to defects due to presence of carbon in the PS layer. The Electron Paramagnetic Resonance (EPR) measurements show the existence of Pb0 and Pb1 centres at the interface Si/SiOx and an other isotropic ray relative to defects due to carbon. It is found that, for red PL, the degree of linear polarisation is relatively important and independent of temperature.
Keywords: Porous silicon; Ageing; Photoluminescence; EPR.