TFT-LCD发绿的研究及改善

TFT-LCD(Thin film transistor-liquid crystal display)行业中,在对屏进行切割、搬运过程中,容易造成屏边缘破损。当破损位置刚好位于屏点银胶位置时,银胶会通过破损进入,与黑矩阵(Black matrix,BM)接触,使黑矩阵带电形成干扰电场,从而使液晶偏转异常而产生发绿不良。切割工艺中,增加辅胶涂覆可以使切割后的空白条更稳定,从而减少搬运过程中摩擦、碰撞导致的屏边缘破损,从而降低不良发生率,导入后不良发生率由5.6%下降到1.5%。屏单侧点银胶是一种具有可行性的不良改善临时措施,但不具有量产导入性。通过对比相似产品银胶点位设计及产线工艺条件调查,得出当银胶点距离屏边缘≥4mm时,可有效防止发绿不良的发生。在点银胶侧BM区域进行挖槽,使银胶与BM隔离开,可彻底避免静电由银胶导入黑矩阵。黑矩阵挖槽设计导入后,发绿不良降低为0%,不良彻底解决。

Investigation and solution of TFT-LCD greenish problem

In the TFT-LCD industry, it is easy to cause Panel edge to be damaged during the cutting and transportation. When the damage position is just at the position of the silver point of the Panel, the silver glue enters through the breakage and contacts with the BM (Black matrix), causing the BM to be charged to form an interference electric field, thereby causing the liquid crystal to deflect abnormally and causing greenish problem. In Cut process, the increase of dummy Seal can make the dummy bar after cutting more stable, thereby reducing the edge breakage caused by friction and collision during transportation, thus reducing the incidence of greenish, after introduction the incidence of greenish is reduced from 5.6% to 1.5%. Panel single-side silver glue point is a feasible temporary improvement measure, but it does not suitable for mass production. By comparing the design of silver glue points of similar products and investigating the process conditions of the production line, we concluded that when the silver glue points are more than 4mm away from the edge of the panel, it can effectively avoid the occurrence of greenish. Make a groove in BM area to separate the silver glue from BM, and the static electricity can be completely prevented from being introduced into the BM by the silver glue. After the introduction of the BM groove design, the greenish failure was reduced to 0%, and the failure was completely solved.