A DC micro plasma jet for local micro deposition of a:C-H film in the ambient vacuum\nof scanning electron microscope (SEM) chamber is proposed. Acetylene (C2H2) gas was locally fed\ninto the chamber through an orifice shaped gas nozzle (OGN) at 6.6 sccm in flow rate by applying\n80 kPa-inlet pressure with an additional direct pumping system equipped on the SEM chamber.\nAs a cathode, a cut of n-type silicon (Si) wafer was placed right in front of the OGN at 200 �¼m gap\ndistance. By applying a positive DC voltage to the OGN, C2H2 plasma was generated locally between\nthe electrodes. During discharge, the voltage increased and the current decreased due to deposition\nof insulating film on the Si wafer with resulting in automatic termination of discharge at the constant\nsource voltage. A symmetric mountain-shaped a:C-H film of 5 �¼m height was deposited at the center\nby operation for 15 s. Films were deposited with variation of gas flow rate, gap distance, voltage\nand current, and deposition time. The films were directly observed by SEM and analyzed by surface\nprofiler and by Raman spectroscopy.
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