Seong-Kweon Heo

2.22‐inch qVGA a‐Si TFT‐LCD using a 2.5 um fine‐patterning technology by wet etch process

Abstract 2.22‐inch qVGA (240×320) amorphous silicon thin film transistor liquid active matrix crystal display (a‐Si TFT‐AMLCD) panel has been successfully demonstrated employing a 2.5 um fine‐patterning technology by a wet etch process. Higher resolution 2.22‐inch qVGA LCD panel with an aperture ratio of 58% can be fabricated as the 2.5 um fine pattern formation technique is integrated with high thermal photo‐resist (PR) development. In addition, a novel concept of unique a‐Si TFT process architecture, which is advantageous in terms of reliability, was proposed in the fabrication of 2.22‐inch qVGA LCD panel. Overall results show that the 2.5 um fine‐patterning is a considerably significant technology to obtain higher aperture ratio for higher resolution a‐Si TFT‐LCD panel realization.