At TFT Array Fabrication production lines, the robots to transfer glasses at atmosphere environment shall follow below guidelines to manage the electrostatics problems.

Figure. a robot used to transfer FPD glasses

1. The vacuum pads to hold TFT glass substrates is the key parts to manage the risks induced by electrostatics.

2. Low electrostatically charging consideration. This includes Lower tribo-charging requirements both to glass substrates and robot vacuum pads after the contact_separation cycle. Use a common non-contact electrostatic field meter to evaluate the low tribo-charging performance regarding the electrostatic sensitivity level of concerned TFT glass products.

3. ESD event suppression consideration. Usually at TFT array fab production lines, the low electrostatic charging of TFT glass substrates and equipment process parts could not be obtained successfully. On these circumstances, the vacuum pads of robots shall avoid being conductive or static dissipative especically for TFT glasses at higher electrostatically charged levels. The pad top point to point resistance and point resistance to Robot ground (test methods could refer to ESD STM11.11, ESD STM11.12, ESD STM11.13 or such tailored evaluation test methods) shall not be too low (eg. greater than 1E6 ohms at the least) and recommended to be Higher as possible.

4. Air ionizations. Air ionizations could be one flexible approach to obtain low electrostatically charging of TFT glasses and equipment process parts and mitigate ESD event risks at most robot applications at TFT Array Fabs. Air ionizations of air ionizers (fan blower and nozzles by compresses air-CDA) by traditional corona discharge technology, soft X-ray ionizers (single head type or bar type of head arrays) could both be easily available.