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We report a continuous three-dimensional pattern with the symmetry of D2h in dielectric barrier discharge by introducing surface discharges (SDs) with a specially designed device for the first time. From the front view, it consists of dark spots and bright bars, which correspond to the conventional volume discharge (VD) and novel VD. Different from the conventional VD, the novel VD bends through three gas gaps and discharges multiple times per half-voltage-cycle, which results from the complex interaction between the VD and SD. By using this device, three surfaces of the sample inserted between electrodes are processed simultaneously, which greatly improves the plasma processing efficiency.

We report on the interaction between surface discharges (SDs) and volume discharges (VDs) in the spot-line white-eye hexagonal superlattice pattern in dielectric barrier discharge using an intensified charge-coupled device camera, a high-speed video camera, and a spectrograph. The small spot-lines and halos discharge in the first pulse and the second pulse at the rising edge of the voltage, respectively. The central spots discharge at the falling edge of voltage. The small spots are VDs whose discharge time is incompletely simultaneous. The lines are direction-selective SDs induced by small spots. It is found that the above phenomena result from the interaction between SDs and VDs. The incompletely simultaneous discharge of the small spots is due to the different quantities of wall charges transported by the SDs induced by small spots. The directional selectivity of the SDs results from that the SDs are extinguished when they are close to halos due to the neutralization of the wall charge of halos (VDs) and the wall charge of SDs, while they can stretch to other small spots.