No abstract

Using an Ar + CH 4 multi-hollow discharge plasma chemical vapor deposition (MHDPCVD) method, carbon nanoparticles (CNPs) are synthesized in a size range between 10 nm and 100 nm at gas pressures from 2 Torr to 5 Torr. The size of the nanoparticles increases from 45.42 nm 3 at 2 Torr to 67.85 nm 3 at 5 Torr. The size dispersion also increases. Conversely, the optical emission intensities and generation of carbon related radicals decrease with increasing pressure. The Raman measurements indicate that these CNPs are composed of polymer structures containing relatively high clustered and distorted sp2 sites.

Carbon nanoparticles (CNPs) incorporated diamond-like carbon (DLC) films have been fabricated by a combination of rf sputtering and plasma chemical vapor deposition. Spherical CNPs with a mean size of 21.2 nm are sandwiched between DLC layers with a mass density of 1.7 g cm−3. The film stress is decreased to 119 MPa, by depositing the CNPs over the base DLC layer at a surface coverage of 10.7%. This reduction is approximately half of that without CNPs. Raman spectroscopy indicates the insertion of CNPs barely alters the bonding structure of the upper DLC layer.

No abstract

As the application of nanotechnology increases continuously, the need for controlled size nanoparticles also increases. Therefore, in this work, we discussed the growth mechanism of carbon nanoparticles generated in Ar+CH4 multi-hollow discharge plasmas. Using the plasmas, we succeeded in continuous generation of hydrogenated amorphous carbon nanoparticles with controlled size (25–220 nm) by the gas flow. Among the nanoparticle growth processes in plasmas, we confirmed the deposition of carbon-related radicals was the dominant process for the method. The size of nanoparticles was proportional to the gas residence time in holes of the discharge electrode. The radical deposition developed the nucleated nanoparticles during their transport in discharges, and the time of flight in discharges controlled the size of nanoparticles.