Characteristics of VUV ionizer in a vacuum chamber of flat panel displays

Flat panel displays are often exposed to the electrostatic damage during various panel manufacturing processes. In this paper, we report the electrostatic discharge failure in a unique process condition of OLED display process during which the substrate of OLED display is turned over while in the vacuum chucking condition. In order to solve this failure, we adopted newly developed technology of VUV (Vacuum Ultraviolet) radiation to neutralize the electrostatic electricity. This technology generates ions and electrons by ionizing residual molecules in vacuum chamber such that it enables the charged substrates to be neutralized in the chamber. While this new neutralization method is certainly effective in high vacuum process, the lifetime and performance of the VUV ionizer are not validated. To understand the lifetime and performance of VUV ionizer, we conducted the experiments in the vacuum chamber of an 8th generation display facility with various operating time of UV lamp. We analyzed the characteristic of VUV lamp and suggested the neutralization mechanism of VUV ionizer in a low pressure. Based on the experiments, this new neutralization method performs well under the high vacuum environment and is able to completely reduce the electrostatic potential down to 0 V within a short time.