Abstract: An upper surface of a ceramic base member has a plurality of projected parts concentrically arranged in a circular pattern. A part of the plurality of projected parts is located in a circular range from 15% to 85% of an outer diameter of the ceramic base member. The average value of the coordinates of a top face of the projected parts in an up-down direction is Z (mm), a radius of the concentric circles is r (mm) and the difference between the radii of adjacent concentric circles is ?r (mm). The absolute value of ?2Z/?r2 is not more than 10?5 (mm?1) or is not more than 10?4/?r (mm?1).

Abstract: An upper surface of a ceramic base member of a ceramic heater includes a plurality of projected parts and a surrounding projected part. The surrounding projected parts surround the periphery of a lift-pin hole. In a case where the height of the surrounding projected part is H1 (m), the height of each of the plurality of projected parts is H2 (m), and a difference (H2?H1) between the height H2 (m) and the height H1 (m) is ? (m), H1<H2 and 1×10?6 (m)??<50×10?6 (m) hold.

Abstract: A first ceramic member and a second ceramic member are joined together at a lower joining temperature while reducing the loss of bond strength. A method for producing a semiconductor production device component includes a step of providing a first ceramic member including an AlN-based material, a step of providing a second ceramic member including an AlN-based material, and a step of joining the first ceramic member and the second ceramic member to each other by thermally pressing the first ceramic member and the second ceramic member to each other via a joint agent including Eu2O3, Gd2O3 and Al2O3 disposed between the first ceramic member and the second ceramic member.

Abstract: A semiconductor production device component includes a first ceramic member including an AlN-based material, a second ceramic member including an AlN-based material, and a joint layer disposed between the first ceramic member and the second ceramic member so as to join the first ceramic member and the second ceramic member to each other. The joint layer includes a composite oxide containing Gd and Al, and Al2O3, and is free from AlN.

Abstract: The scattering of a rare earth hydroxide is suppressed, and the loss of bond strength between a first ceramic member and a second ceramic member is reduced. A semiconductor production device component includes a first ceramic member including an AlN-based material, a second ceramic member including an AlN-based material, and a joint layer disposed between the first ceramic member and the second ceramic member so as to join the first ceramic member and the second ceramic member to each other, wherein the joint layer includes a perovskite oxide represented by ABO3 (wherein A is a rare earth element, and B is Al) and includes no rare earth single oxide containing exclusively a rare earth element and oxygen.

Abstract: A first ceramic member and a second ceramic member are joined together at a lower joining temperature while reducing the loss of bond strength. A method for producing a semiconductor production device component includes a step of providing a first ceramic member including an AlN-based material, a step of providing a second ceramic member including an AlN-based material, and a step of joining the first ceramic member and the second ceramic member to each other by thermally pressing the first ceramic member and the second ceramic member to each other via a joint agent including Eu2O3, Gd2O3 and Al2O3 disposed between the first ceramic member and the second ceramic member.

Abstract: A semiconductor production device component includes a first ceramic member including an AlN-based material, a second ceramic member including an AlN-based material, and a joint layer disposed between the first ceramic member and the second ceramic member so as to join the first ceramic member and the second ceramic member to each other. The joint layer includes a composite oxide containing Gd and Al, and Al2O3, and is free from AlN.