The photoluminescence(photoluminescence)spectra of PS(porous silicon)prepared via electrochemical etching are presented and analysed.The PL of samples was measured at various temperatures.The corresponding parameters ...The photoluminescence(photoluminescence)spectra of PS(porous silicon)prepared via electrochemical etching are presented and analysed.The PL of samples was measured at various temperatures.The corresponding parameters of peaks(energy,intensity and FWHM)were calculated using a fitting procedure,where the PL spectrum was approximated by a set of Gaussian peaks.This model is based on the presumption that the emission of photons in the PL process represents independent events.The optimal number of peaks used in the model was estimated,where the residuum of the approximation was used as a criterion.The low thermal dependence of energies in the PL spectra(blue shift)indicates the strong influence of defects on the position of corresponding PL maxima.The observed increase of energies of peaks with temperature requires additional explanation.展开更多
The paper deals with the complex refractive index and photoluminescence in the IR-VIS light region of two sample types (i) black p-type silicon (BSi) produced by the surface structure chemical transfer method usin...The paper deals with the complex refractive index and photoluminescence in the IR-VIS light region of two sample types (i) black p-type silicon (BSi) produced by the surface structure chemical transfer method using Pt catalytic mesh, and (ii) porous p-type silicon prepared by standard electrochemical etching. We present, compare, and discuss the values of the IR-VIS complex refractive index obtained by calculation using the Kramers-Kronig transformation and the photoluminescence properties thereof. The results indicate that differences between the optical properties of the BSi and the porous Si are given by (a) the oxidation procedure of BSi, (b) the thickness of the formed black and porous Si layer, and by (c) the porosity of both layer types. We assume that the photoluminescence signal generated by oxidized BSi structures can be mainly related to the quantum confinement effect, while the photoluminescence of the porous p-type Si is caused by the optical activity of the SiOxHy compounds covering its surface region.展开更多
文摘The photoluminescence(photoluminescence)spectra of PS(porous silicon)prepared via electrochemical etching are presented and analysed.The PL of samples was measured at various temperatures.The corresponding parameters of peaks(energy,intensity and FWHM)were calculated using a fitting procedure,where the PL spectrum was approximated by a set of Gaussian peaks.This model is based on the presumption that the emission of photons in the PL process represents independent events.The optimal number of peaks used in the model was estimated,where the residuum of the approximation was used as a criterion.The low thermal dependence of energies in the PL spectra(blue shift)indicates the strong influence of defects on the position of corresponding PL maxima.The observed increase of energies of peaks with temperature requires additional explanation.
文摘The paper deals with the complex refractive index and photoluminescence in the IR-VIS light region of two sample types (i) black p-type silicon (BSi) produced by the surface structure chemical transfer method using Pt catalytic mesh, and (ii) porous p-type silicon prepared by standard electrochemical etching. We present, compare, and discuss the values of the IR-VIS complex refractive index obtained by calculation using the Kramers-Kronig transformation and the photoluminescence properties thereof. The results indicate that differences between the optical properties of the BSi and the porous Si are given by (a) the oxidation procedure of BSi, (b) the thickness of the formed black and porous Si layer, and by (c) the porosity of both layer types. We assume that the photoluminescence signal generated by oxidized BSi structures can be mainly related to the quantum confinement effect, while the photoluminescence of the porous p-type Si is caused by the optical activity of the SiOxHy compounds covering its surface region.