Study of cutting quality for TFT-LCD glass substrate

The trend towards using a large area of thin-film transistor liquid crystal display (TFT-LCD) glass substrate introduces challenges for cutting quality and production yield. For the requirements of boosting manufacturing efficiency and reducing cost, the optimization of cutting parameters becomes very important. In this study, we use a cutting wheel to directly scribe the glass substrate so as to generate a cutting score depth of the glass. The glass is then cleaved utilizing the principles of mechanical stress. We investigate quality issues such as median crack, lateral crack, cutting score, and cleaved profile with respect to different cutting pressures and wheel depths, which are in the ranges of 0.16 to 0.24 MPa and 0.1 to 0.3 mm, respectively, with a cutting speed of 350 mm/s. The glass substrate for the experiment is Corning EAGLE 2000 with a thickness of 0.7 mm. It is found that the median and lateral crack length can reach 140 and 403 μm, respectively, when the cutting pressure increases to 0.24 MPa.