Determination of Raman emission cross-section ratio in hydrogenated microcrystalline silicon

Abstract

The determination of the crystalline volume fraction from the Raman spectra of microcrystalline silicon involves the knowledge of a material parameter called the Raman emission cross-section ratio y. This value is still debated in the literature. In the present work, the determination of y has been carried out on the basis of quantitative analysis of medium-resolution transmission electron microscopy (TEM) micrographs performed on one layer deposited by very high frequency plasma enhanced chemical vapor deposition (VHF-PECVD) close to the amorphous/microcrystalline transition. Subsequent comparison of these data with the crystallinity as evaluated from measured Raman spectra yields a surprisingly high value of y = 1.7. This result is discussed in relation to previously published values (that range from 0.1 to 0.9).

Effect of grain size and hydrogen passivation on the electrical properties of nanocrystalline silicon films

“…Although the values of y that have been used for mixed-phase silicon vary considerably, the most recent data indicate that 2 1   y [14,15]. In this work we used 7 .…”

Input silane concentration effect on the a-Si:H to μc-Si:H transition width

“…The RF power input was kept constant within each series, but was adjusted to have the different Before the deposition of the layers studied in this paper, a highly microcrystalline layer was deposited on glass in order to avoid amorphous incubation layers [10]. The crystalline fraction of the layers was analyzed by micro-Raman spectroscopy [11].…”

Silane depletion dependent ion bombardment and material quality of microcrystalline silicon deposited by VHF-PECVD

“…During deposition, the peak to peak voltage V pp was measured on the RF driven electrode using a calibrated high impedance capacitive gauge connected to an oscilloscope. The samples were analyzed by micro Raman spectroscopy [8]. Solar cells were deposited in the p-i-n configuration in the same reactor in a single chamber process on ZnO coated glass substrates [9].…”