Hybrid LCVD of micro-metallic lines for TFT-LCD circuit repair

The deposition of micrometer-scale metallic lines by laser chemical vapor deposition (LCVD) on glass is investigated for the repair of open-circuit type defects of thin film transistor-liquid crystal display (TFT-LCD) panels. In this work, a third harmonic Nd:YLF laser (351 nm) of high repetition rates was used as the illumination source and W(CO)(6) was selected as the reaction material for the deposition of tungsten interconnects on glass substrate. General characteristics of the tungsten deposit such as height, width, morphology as well as electrical resistivity were examined for various process conditions. Height of the deposited tungsten lines ranged from 35 to 500 nm depending on laser power and scan speed while the width was controlled in the range of 3-50 mu m by adjusting the size of a slit placed in the beam path. The resistivity of deposited tungsten lines was measured to be below 1 Omega mu m. The tungsten deposit is considered to form through a hybrid process, namely through the combination of photolytic and pyrolytic mechanisms. The deposited tungsten lines developed in this study are successfully applied for the repair of TFr-LCD circuit defects without damaging the glass substrate. (c) 2006 Elsevier B.V. All rights reserved.