P‐54: Research On DGS Character Of Glass Based Mini LED BLU

Abstract

This paper introduces the research on the elements that could lead to the DGS issue of Mini LED BLU, as well as a theoretical model built based on the research result. By performing a variety of experiments studying the relationship between several elements, this DGS issue was confirmed to be caused by electrochemical corrosion under the joint impact of water steam infiltrate and electric potential difference between metal pattern on the product. In this specific circumstance, the two necessary condition for DGS issue to happen are electric potential difference between 2 nd Cu layer pattern in LED zone and 1 st Cu layer pattern on the G‐ bus, and the water steam infiltrated from the via hole left for the LED chip soldering. The water steam infiltrated then diffuse through the 1 st Resin layer and the time cost for the water steam to reach the position where electric potential difference exists is in a direct proportion to the distance from such point to the soldering via. Moreover, the larger that electric potential difference is, the higher probability of DGS issue happening is, while the relationship between this probability and the distance mentioned previously is in an opposite way. Overall, by applying several optimization such cancelling the hedgehopping 1 st Cu pattern and adding extra inorganic insulating layer protection on the design of product, and applying an extra cathode protection design, the DGS issue was significantly resolved.