Ground substrate and method for producing same
AssigneeNGK Insulators, Ltd.
InventorsMorimichi Watanabe, Jun Yoshikawa
Life of this patent
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Abstract
Provided is a base substrate including an orientation layer used for crystal growth of a nitride or oxide of a Group 13 element. A front surface of the orientation layer on a side used for crystal growth is composed of a material having a corundum-type crystal structure having an a-axis length and/or c-axis length larger than that of sapphire. The orientation layer contains a solid solution containing two or more selected from the group consisting of α-Al2O3, α-Cr2O3, α-Fe2O3, α-Ti2O3, α-V2O3, and α-Rh2O3.
Claims14
A base substrate comprising an orientation layer used for crystal growth of a nitride or oxide of a Group 13 element,
- wherein a front surface of the orientation layer on a side used for the crystal growth is composed of a material having a corundum-type crystal structure having an a-axis length and/or c-axis length larger than that of sapphire,
- wherein the orientation layer contains a solid solution containing two or more selected from the group consisting of α-Al2O3, α-Cr2O3, α-Fe2O3, α-Ti2O3, α-V2O3, and α-Rh2O3,
- wherein a gradient composition region having a composition varying in a thickness direction is present in the orientation layer, and
- wherein the a-axis length and/or the c-axis length on the front surface of the orientation layer is longer than an a-axis length and/or a c-axis length on a rear surface of the orientation layer by 2.5% or more.
Dependencies are inferred from the claim text.