Influence of Pores on Transparent Thick Films Formed by Several Coating Methods

초록

One of the most important factors of transparent dielectric is high transmittance. Transmittance is under the influence of pore contents, pore size and frit size. If pores remained on the fired thick film, transmittance and withstanding voltage will be decreased. This study investigated the effect of coating methods on transmittance of thick films using a zinc-boric glasses system. Mixed glass paste was used for thick films, which were made by screen printing, tape casting and die coater methods, on a glass substrate (PD200). These fired thick films were measured for surface roughness, pore size, porosity and transmittance. As a result, the screen printing method had non-uniform surface and increased pores with multilayer. Tape casting and die coater methods, however, produced more uniform surface and less pore content compared to the screen printing method. Thus it shows that increase of pore size and contents has detrimental effects on the transmittance of thick films.