Levitation of cylindrical particles in the sheath of an rf plasma - art. no. 036406

Microrods were levitated in the collisional sheath of a rf plasma. Rods bel ow a critical length settle vertically, parallel to the electric field, whi le longer rods float horizontally. Usually rods with other inclinations spi n about a vertical axis. These experimental features Bt well with a model t hat includes a theoretical profile for the sheath, a plasma model for the s creening length, which increases going deeper in the sheath, and a plasma t heory for the charging of the rod's elements. Despite the agreement this pa per highlights the need for a better understanding of the charging mechanis m of bodies in sheaths and of the transition region in collisional sheaths.