H. Ibe, F. Yuasa, H. Mizuno, Fujimi Incorporated, Kakamigahara, Gifu, Japan; K. Sato, J. Kitamura, Fujimi incorporated, Kakamigahara, Japan
Yttrium oxide coatings with high erosion resistance by plasma spraying are widely applied to shielding parts onto aluminum based inside chamber wall of dry etching equipments to protect from halogen contained plasma in semiconductor and electronic devices industries. Continuous development of device integration and improvement of production efficiency of the devices strongly requires improvement of erosion resistance and lower particle generation of the shielding parts Therefore, improvement of properties of yttrium oxide coatings is still necessary to satisfy the requirement. Influence of the primary particle size of the agglomerated-and-sintered yttrium oxide powder on structural, mechanical and plasma-erosion properties has been studied in this study, where fine, medium (conventional) and coarse sized particles have been used. Conditions, especially powder feeding rate, of conventional 40 kW type plasma spraying apparatus with radial internal powder injection have been also focused to understand their influence on the coating properties. This study will describe important process parameters and these will be a optimal way to improve the properties.
Summary: This paper describes the practical way to improve the coating properties of yttrium oxide by plasma spraying for shileding parts in dry etching systems. We changed the primary particle size of agglomerated-and-sintered powder as feedstock and also investigated the influence of spray conditions especially about powder feeding rate that easily changes injection of powder into the plasma flame. Therefore, practical way will be shown in many spray shops for the improvement of coating properties, including erosion resistance against CF4 plasma.
