Synthesis of nanopowders in a PECVD reactor from organosilicon precursor

Abstract

In previous work, nanopowders have been obtained during the deposition of thin layers from Hexamethyldisiloxane (HMDSO) using low frequency plasma. The aim of this work is the study of the growth process of these nanopowders in plasma discharge and in deposited films. The plasma discharge was generated from HMDSO precursor in low frequency reactor; optical emission spectroscopy (OES) and scanning electron microscopy (SEM) have been used to investigate the effect of the deposition parameters on the nanopowders growth in the plasma discharge and in the deposited thin layers respectively. For high deposition pressure, OES reveals the presence of SiH (situated at 414 nm), OH (situated at 309 nm), CHO (situated at: 324.3, 351.5 nm) species and some additional emission peaks of CO (situated at: 540.9, 566.6, 578, 646,6 nm). The intensities evolution of these species have been investigated during the discharge plasma and the presence of some of them may be the result from the reaction of the nanoparticles of the deposited powders with the plasma species. Nanoparticles agglomerations have been revealed by SEM observations and their aspect correlated with optical emission spectroscopy measurements.