Synthesis of diamond films on Hastelloy

Abstract

We have developed a two-step hot filament chemical vapor deposition method to form polycrystalline films of diamond on Hastelloy substrates. The first step at a lower temperature results in the deposition of a composite layer of carbon, diamond-like carbon, and diamond, which provide nucleation sites for diamond growth in the second step at a higher temperature. To obtain a cleaner amorphous carbon-free diamond film, we introduced an intermediate hydrogen etching step. Using this procedure, we have obtained high quality polycrystalline diamond film on Hastelloy substrates, as characterized by scanning electron microscopy and Raman measurements.