Sputtering Technology of TiO₂ Films Coated onto the Fine Particles

Abstract

TiO₂ films have been deposited onto the surface of the organic powders composed of the fine particles by dc facing targets sputtering in a mixture gas of Ar and O₂. During exhaustion in the sputtering chamber, the fine particles were scattered from the vessel vibrated by sound pressure. The sputtering could not be performed for a long time by the unstable discharge due to the scattered particles. To prevent this, the stainless steel mesh plate was placed on the vessel with a distance of 5 mm. AC voltage V_A of 60 Hz was applied to the stainless steel mesh plate with mesh size D_M varying from 2 to 8 mm. The scattering amount of the fine particles significantly depended on the V_A and the D_M. The scattering amount of the fine particles steeply decreased from 8 to 1.5g with increasing V_A in the range from 50 to 150V, where the D_M and the total amount of the fine particles are 2mm and 30g, respectively. With further increase of V_A in the range from 150 to 250V, the scattering amount of the fine particles steeply increased. At V_A of 150V, the scattering amount of the fine particles has a minimum value. On the other hand, the scattering amount of the fine particles monotonically increased from 1.5 to 15g with increasing D_M in the range from 2 to 8mm, where the V_A and the total amount of the fine particles are 150V and 30g, respectively. It has found that the larger mesh size is the more scattering amount of the fine particles.