Film growth mechanism of photo-chemical vapor deposition

Photo-CVD process for ultra thin SiO2 films

“…It has also been observed when, depositing Si 3 N 4 using Si 2 H 6 and NH 3 , [5], that the deposition rate starts to increase with the distance between lamp and substrate, reaches a maximum and starts again to decrease. This behavior can be explained considering that the deposition rate depends on the number of active species striking the wafer, which will depend on light intensity (for the correct range of wavelength capable of producing the photolysis of the gas) on the concentration of active species at a given distance from the substrate and on pressure.…”

“…Low pressure mercury lamp [2,3], deuterium lamp [1], microwave excited argon discharge lamp [4] and a 200 mJ, 50 Hz, 23 ns duration pulse ArF laser [7] are some of the light sources reported for photo-dissociation of the above mentioned gases. Deposition of Si 3 N 4 using a low pressure mercury lamp has also been reported [5].…”