Properties and applications of a modified dielectric barrier discharge generated at atmospheric pressure

An atmospheric pressure plasma was generated using a modified dielectric barrier discharge with the power electrode composed of multi-pins (i.e., a pin-to-plate type) instead of a conventional blank plate (i.e., a DBD-type), and the discharge and the photoresist etching characteristics were compared with those produced by the DBD-type at various He/O₂ mixtures. The pin-to-plate type showed a higher discharge current and a higher power consumption than the DBD-type at a given voltage. Therefore, the pin-to-plate type appeared to be more efficient than the conventional DBD-type. In addition, when the photoresist etch rate was examined, the pin-to-plate showed higher etch rates than the DBD-type at various He/O₂ mixtures. For the He/O₂ mixture, both types showed the maximum photoresist etch rate at a certain He/O₂ mixture. Using a gas mixture of 3 slm of O ₂ and 10 slm of He, a maximum photoresist etch rate of 340 nm/min and 260 nm/min could be obtained using the pin-to-plate type and the DBD-type, respectively, at 10 kV AC for an electrode size of 500mm × 50mm. No physical damage was observed on the metal lines of the TFT-LCD devices after photoresist etching under the above conditions.