Patent ID: 6447937
Filing Date: 2002-09-10
Classification: C04B,Y10T

Abstract:
A ceramic material resistant to halogen plasma comprising a composite metal oxide, wherein the composite metal oxide includes a metal selected from the group consisting of Scandium, Yttrium, Lanthanum, Cerium, Neodynium, Samarium, Europium, Terbium, Dysprosium, Holmium, Erbium, Thulium, Ytterbium and Lutetium, and Al and/or Si, and wherein the ceramic material contains less than about 0.15% of metals other than the metal forming the composite metal oxide, wherein the porosity of the ceramic material is not more than 3% and the surface of the ceramic material is not more than 1 micron meter in center line average roughness Ra.