Pore-free ceramic component
AssigneeSchott AG
InventorsBianca Schreder, Ute Wölfel, Stefanie Hansen
Life of this patent
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Abstract
A pore-free ceramic is provided that has a high modulus of elasticity and a low coefficient of thermal expansion. A process for producing a corresponding ceramic is also provided. The pore free ceramic is a dimensionally stable substrate material in applications subjected to temperature gradients including semiconductor manufacture.
Claims25
A ceramic component comprising a ceramic produced from a vitreous solid glass precursor having the following composition, in % by weight on an oxide basis:
- SiO2 40-55;
- Al2O3 21-35;
- MgO 10-15;
- TiO2 1-less than 7;
- ZrO2 1-8;
- a total of TiO2 and ZrO2 from greater than 6 to 11% by weight on an oxide basis,
- wherein the ceramic has a first crystal phase having a proportion of indialite that is at least 60% and has a secondary crystal phase comprising rutile and ZrTiO4, wherein the secondary crystal phase is present as seed crystallites located in an interior of, or next to, the first crystal phase;
- and
- a modulus of elasticity of at least 130 GPa;
- a coefficient of linear thermal expansion α(0-50) of not more than 1×10−6/K;
- a ratio of the modulus of elasticity to a density in g/cm3 that is at least 50;
- and
- a porosity of less than 0.1%.
A ceramic component comprising a ceramic produced from a vitreous solid glass precursor having the following composition, in % by weight on an oxide basis:
- SiO2 40-55;
- Al2O3 21-35;
- MgO 10-15;
- TiO2 1-less than 7;
- ZrO2 1-8;
- a ratio of TiO2 to ZrO2 from 0.7 to 1.7,
- wherein the ceramic comprises a first crystal phase having a proportion of indialite that is at least 60% and a secondary crystal phase comprising rutile and ZrTiO4, wherein the secondary crystal phase is present as seed crystallites located in an interior of, or next to, the first crystal phase;
- and
- a modulus of elasticity of at least 130 GPa;
- a coefficient of linear thermal expansion α(0-50) of not more than 1×106/K;
- a second ratio of the modulus of elasticity to a density in g/cm3 that is at least 50;
- and
- a porosity of less than 0.1%.
A ceramic component comprising a ceramic produced from a vitreous solid glass precursor having the following composition, in % by weight on an oxide basis:
- SiO2 40-55;
- Al2O3 21-35;
- MgO 10-15;
- TiO2 1-less than 7;
- ZrO2 1-8;
- a total of TiO2 and ZrO2 from greater than 6 to 11% by weight on an oxide basis,
- wherein the vitreous solid glass precursor is ceramicized to provide the ceramic having a crystal phase of at least 60%, the crystal phase having a main crystal phase indialite and a secondary crystal phase present as seed crystallites selected from the group consisting of rutile, ZrTiO4, and combinations thereof, the main crystal phase having been grown on the seed crystallites;
- a modulus of elasticity of at least 130 GPa;
- a coefficient of linear thermal expansion α(0-50) of not more than 1×106/K;
- a ratio of the modulus of elasticity to a density in g/cm3 that is at least 50;
- and
- a porosity of less than 0.1%.
A ceramic component comprising a ceramic produced from a vitreous solid glass precursor having the following composition, in % by weight on an oxide basis:
- SiO2 40-55;
- Al2O3 21-35;
- MgO 10-15;
- TiO2 1-less than 7;
- ZrO2 1-8;
- a ratio of TiO2 to ZrO2 from 0.7 to 1.7;
- a modulus of elasticity of at least 130 GPa;
- a coefficient of linear thermal expansion α(0-50) of not more than 1×10−6/K;
- a total spatial variation of the coefficient of linear thermal expansion over the total ceramic component that is not more than 0.5 ppm/K;
- a porosity of less than 0.1%;
- and
- a second ratio of the modulus of elasticity to a density in g/cm3 that is at least 50,
- wherein the ceramic comprises a first crystal phase having a proportion of indialite that is at least 60% and a secondary crystal phase present as seed crystallites selected from a group consisting of rutile, ZrTiO4, and combinations thereof.
Dependencies are inferred from the claim text.