Lithium tantalate substrate and method for producing same
AssigneeSumitomo Metal Mining Co., Ltd.
InventorsTomio Kajigaya, Takashi Kakuta
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Abstract
A lithium tantalate substrate obtained by working in the state of a substrate a lithium tantalate crystal grown by the Czochralski method is buried in a mixed powder of Al and Al2O3, followed by heat treatment carried out at a temperature kept to from 350 to 600° C, to manufacture a lithium tantalate substrate having volume resistivity which has been controlled within the range of from 106 to 108 Ωcm. The substrate obtained has no piezoelectricity, and it can be made colored and opaque from a colorless and transparent state and also sufficiently has the properties required as a piezoelectric material.
Claims4
A process for manufacturing a lithium tantalate substrate by using a lithium tantalate crystal grown by the Czochralski method, wherein;
- a lithium tantalate crystal worked in the state of a substrate is buried in a mixed powder of 75% by weight of Al and 25% by weight of Al2O3, followed by heat treatment carried out at a temperature kept from 350 to 600° C. for 20hours in an atmosphere of nitrogen gas and under reduced pressure, to manufacture a lithium tantalate substrate having volume resistivity which has been controlled within the range of from 106to 108 Ωcm.
A process for manufacturing a lithium tantalate substrate by using a lithium tantalate crystal grown by the Czochralski method, wherein;
- a lithium tantalate crystal worked in the state of a substrate is buried in a mixed powder of 10% by weight of Al and 90% by weight of Al2O3, followed by heat treatment carried out at a temperature kept from 350 to 600° C. for 80hours in an atmosphere of nitrogen gas and under reduced pressure, to manufacture a lithium tantalate substrate having volume resistivity which has been controlled within the range of from 106to 108 Ωcm.
A process for manufacturing a lithium tantalate substrate by using a lithium tantalate crystal, grown by the Czochralski method, wherein;
- a lithium tantalate crystal worked in the state of a substrate is buried in a mixed powder of 75% by weight of Al and 25% by weight of Al2O3, follow by heat treatment carried out at a temperature of 550° C. for 80hours in an atmosphere of nitrogen gas and under atmospheric pressure, to manufacture a lithium tantalate substrate having volume resistivity which has been controlled within the range of from 106 to 108 Ωcm.
A process for manufacturing a lithium tantalate substrate by using a lithium tantalate crystal grown by the Czochralsld method, wherein;
- a lithium tantalate crystal worked in the state of a substrate is buried in a mixed powder of 50% by weight of Al and 50% by weight of Al2O3, followed by heat treatment calmed out at a temperature of 550° C. for 20 hours in an atmosphere of vacuum, to manufacture a lithium tantalate substrate having volume resistivity which has been controlled within the range of from 106to 108 Ωcm.
Dependencies are inferred from the claim text.