New nanoporous low dielectric constant material for TFT passivation

Abstract

Nano-porous containing photo-sensitive materials can be used in TFT-LCD color filter. It is a critical material in color filter on array(COA) manufacturing. Nano-porous material has high light transmittance, high resolution. Band low dielectric constant which can increase the aperture ratio of TFT-LCD display panel. Advantages of low exposure dose, high sensitivity and high resolution can be provided by applying cationic photo acid generator (PAG) in photo sensitive materials. In this paper, chain breakages were produced by photo chemical reaction between the tert-butyl side chain containing polymer and PAG. The butene produced from chain breakages of methacrylate polymer will become nano-porous which is critical to low dielectric constant in materials. The Montomorillonite(MMT) was use as nano-reactor. PAG were inserted between MMT layers though intercalating reaction. The d-spacing was thus increased. By measuring the changes in d-spacing with X-ray, the intercalating reaction between PAG & MMT was shown. The reaction mechanism of nano-porous formation in photo sensitive materials after UV exposure were studied with EPR. Furthermore, MTEM has been used to observe the amount of nano-porous and the hole size in order to study the interrelation among nano-porous.