PULSED PLASMA-PULSED INJECTION SOURCES FOR REMOTE PLASMA ACTIVATED CHEMICAL VAPOR-DEPOSITION

Remote plasma activated chemical vapor deposition (R-PACVD) is an attractive fabrication technique owing to the increased selectivity of radical generation which can be obtained compared to deposition techniques in which the substrate is immersed in the plasma. This selectivity can be compromised if the deposition gases, which are typically injected downstream of the plasma zone, back-diffuse into the plasma where indiscriminate electron impact dissociation occurs. In this communication, a new RPACVD technique is described in which the plasma and injected gases are sequentially pulsed to temporally isolate the injected gases from the plasma. This method reduces, or eliminates, indiscriminate dissociation of the injected gases and improves the selectivity of radical fluxes to the substrate.