High pressure diamond and diamond-like carbon deposition using a microwave CAP reactor

Abstract

This paper describes the deposition of diamond and diamond-like carbon coatings using the Circumferencial Antenna Plasma (CAP) reactor. Carbon coatings were deposited at pressures of 8000, 5000 and 3300 Pa onto silicon wafers. The coatings were characterised using electron microscopy and Raman spectroscopy as a function of distance from the centre of the substrate holder. At 8000 Pa, diamond coatings were deposited up to 20 mm from the centre of the silicon wafer, while under the same deposition conditions, diamond-like carbon was observed in an annular region between 62 and 75 mm from the centre. At a deposition pressure of 5500 Pa, homogeneous free-standing diamond films, 120 μm thick and 50 mm in diameter were deposited.