Dynamic behaviors of fine diamond-particles levitated in low-pressure plasmas are investigated. Fine diamond-particles injected into the plasma are charged up negatively and confined electrically above a radio frequency (RF) powered electrode at some vertical position where the gravity force acting on the particles balances with the electric force in the sheath region in front of the RF electrode. The average size of the diamond particles employed here is ∼2 μm. We observed that the diamond particles reveal strong motions in the lower-pressure discharge plasma. These motions are quite random and the equivalent kinetic temperature attained is ∼ 10 eV which is higher than the thermal level of the particles. The motion is gradually suppressed in the higher-pressure regime. The mechanisms of the diamond particle behaviors are discussed.
ASJC Scopus subject areas
- 化学 (全般)