ATR-FTIR, DUAL BEAM FIB-SEM, TEM and TOF-SIMS studies on high temperature and moisture induced “white haze” following the pattern of electrodes in touch panels

White haze or the so called mura effect has been recognized as a common defect in touch panels. Nevertheless, the underlying mechanism has not been fully understood and clearly investigated. In this study, a comprehensive characterization study using the ATR-FTIR, DUAL BEAM FIB-SEM, TEM and TOF-SIMS on the high temperature and moisture induced white haze, which follows the pattern of electrodes in touch panels, is first reported. It is suspected that the white haze is a moisture induced reflection alteration phenomenon of the OCA (optically clear adhesive), while the electrodes related pattern is highly dependent on the local variation in hygroscopic swelling.