TFT-LCD白画面边缘发青不良机理分析及改善研究

Study of Mechanism and Improvement of Blue Color on Edge of Panel of TFT-LCD under White Image

TFT-LCD(Thin Film Transistor-Liquid Crystal Display)在显示白画面的时候,屏幕边缘有发青的现象,这种不良现象严重影响人们的观赏感受,需要将这种不良进行改善。经过分析得知,TFT(Thin Film Transistor)基板的层间介质层(interlayer dielectrics,ILD)的氢化氮化硅(SiN_X:H)薄膜厚度偏薄,致使TFT基板的蓝光透过率偏大,从而导致TFT-LCD在显示白画面时,白光中蓝色光的比例偏大,最终出现发青现象。通过增加SiN_X:H薄膜的沉积厚度及减少SD(Source and Drain)干法刻蚀时间,使无SD覆盖的ILD膜层的SiN_X:H薄膜厚度增加,减小了TFT基板的蓝光透过率,最终TFT-LCD的白画面颜色均匀,无发青现象。

Under the white image,it is blue on the edge of the panel of TFT-LCD（Thin Film TransistorLiquid Crystal Display）. And this phenomenon seriously affects people＇s viewing experience,and needs to be improved. Based on the analysis of TFT-LCD,it is found that the thickness of hydrogenated silicon nitride of interlayer dielectric on TFT Substrate is small and the transmissivity of blue light is large. Under the white image,the proportion of the blue light of white light is large,so it is blue on the edge of the panel. By increasing the thickness of hydrogenated silicon nitride and reducing the time of SD（Source and Drain） dry etching,the thickness of hydrogenated silicon nitride which is not covered with SD becomes large,and the transmissivity of blue light becomes small,finally the uniformity of color of panel is very good.