Densification behavior of yttrium oxyfluoride ceramics by rate controlled sintering and their mechanical properties

Although yttrium oxyfluoride (YxOyFz) ceramics are considered as promising next-generation corrosion-resistant materials for the prevention of particulate contaminations occurring during plasma etching process in semiconductor industry, the application of pressure during their sintering makes manufacturing of these ceramics quite complicated. Here, we report a simple method of densification of Y5O4F7 + YF3 ceramics based on pressureless rate-controlled sintering (RCS). The heating program with a constant shrinkage rate was calculated based on the densification behavior, which was investigated preliminary using dilatometry. The open porosity of Y5O4F7 + YF3 ceramics fabricated by RCS is 0.1%; That is, RCS allowed us to achieve a high degree of densification. As a result, the three-point bending strength of 180 ± 14 MPa, which exceeded that of hot-press sintered samples, was achieved.