Analytical Methodology Development for Silicon-rich-oxide Chemical and Physical Characterization

Silicon-rich-oxide (SRO) layers and silicon nano-crystals (Si-nc) have been gaining particular attention for their optoelectronic properties. Analytical techniques as secondary ion mass spectrometry (SIMS), photo-electron spectroscopy (XPS), variable angle spectroscopy ellipsometry (VASE) and atomic force microscopy (AFM) were considered in this work as helpful ways to obtain the required characterization of these materials. SRO different films were deposited on Si wafers by plasma enhanced chemical vapor deposition (PECVD) and varying the ratio between SiH4, N2O and NH3. Then they were analyzed by SIMS and XPS, which combine the chemical physical analytical techniques requested to provide quantitative and accurate results. Besides the high precision of SIMS profiles, the accuracy of the data in SRO is marked as a difficult task, because of different matrices in different films. Therefore a fit equation for silicon SIMS depth profiles quantification in SRO is proposed. The physic-chemical data were related to VASE measurements. Furthermore the structural properties of silicon nano-crystals were investigated by AFM. The developed methodology confirms undoubtedly the Si-nc growth