Glass-ceramics with plasma resistance and parts for dry etching comprising the same
A crystallized glass includes crystalline and vitreous structures, in which the crystalline structure includes lithium disilicate as a main crystalline phase and at least one crystalline phase among lithium phosphonate (Li 3 PO 4 ), lithium metasilicate (Li 2 SiO 3 ), silica (SiO 2 ), and zirconia (ZrO 2 ) as a sub-crystalline phase, has an excellent processability and an excellent plasma corrosion resistance, thereby being useful as a material for production of parts for various dry etching apparatuses.
1 . A crystallized glass comprising a crystalline structure and a vitreous structure,
wherein the crystallized glass contains 40% to 80% by weight of the crystalline structure,
wherein the crystalline structure comprises lithium disilicate as a main crystalline phase and at least one crystalline phase of lithium phosphate (Li 3 PO 4 ), lithium metasilicate (Li 2 SiO 3 ), silica (SiO 2 ), or zirconia (ZrO 2 ) as a sub-crystalline phase,
wherein the crystalline structure contains 60% to 95% by weight of the lithium disilicate as the main crystalline phase,
wherein the crystallized glass has a surface roughness of 0.01 μm to 0.1 μm,
wherein the main and sub-crystalline phases have an average grain size of 0.05 μm to 0.5 μm after performing a primary crystallization heat treatment at a temperature in the range of 400° C. to 850° C.,
wherein the main and sub-crystalline phases have an average grain size of 0.5 μm to 5 μm after performing a secondary crystallization heat treatment at a temperature in the range of 800° C. to 950° C. after the primary crystallization heat treatment, and
wherein the crystallized glass has plasma corrosion resistance required for dry etching process.