Carbonaceous nano dusty plasma synthesis in weakly magnetized nonthermal plasma

Carbonaceous dusty nanoparticles are commonly synthesized from acetylene in low-temperature argon plasmas. Their growth follows a cyclic pattern—particles increase in size until they reach a critical radius beyond which they can no longer be confined by the plasma, causing them to move away from the bulk region. A new generation of particle growth immediately follows. We have grown particles across a range of chamber pressures (P = 13.3 to 93.3 Pa / 100 to 700 milliTorr) and background magnetic field strengths (B = 20 to 1000 Gauss). Here, we present how the cycle time varies with these parameters. The presentation will show that with the application of even weak magnetic fields (B < 50 Gauss), there is a dramatic reduction in the cycle time by a factor of 2. This reduction persists until a magnetic field ~250-350 Gauss (at 500 milliTorr), where the electron transport becomes dominated by the magnetic field, beyond which there is a saturation and evidence of a slow increase in the cycle time. COMSOL Multiphysics simulations of the background argon plasma as a function of the experimental parameters may also be presented.