A method for depositing a coating includes creating a vacuum within an interior volume of a tubular structure, wherein the tubular structure also includes an internal surface. Gas is supplied to the interior volume of the tubular structure, wherein the gas includes a plasma precursor in the gas phase. The tubular structure is biased relative to ground. Plasma having a density is formed and cyclically positioned along the length of the tubular structure. Positive ions of the plasma precursor gas are generated and are deposited on the internal surface forming a coating on the internal surface, wherein the coating exhibits a water contact angle of greater than 120.degree.
Michael A. Miller; Ronghua Wei; Gregory J. Hatton