Abstract: A leading-end protective layer of a sensor element includes: an inner layer covering a leading end surface and four side surfaces of an element base; and an outer layer covering the inner layer and having a lower porosity than the inner layer, and a film thickness variation degree, defined as a ratio of a difference between a maximum and a minimum value of total thicknesses of the leading-end protective layer at following positions with respect to an average value of the total thicknesses when the value is based at 100, is 20 or less: two positions to intersect with the protective layer, on planes passing through line intersections of an imaginary plane containing the end surface and imaginary planes containing main surfaces of the element base, and forming an angle of 45° with the former imaginary plane, and an intermediate position in an element thickness direction on the end surface.

Abstract: A sensor element includes a porous leading-end protective layer disposed around an outer periphery of an element base in a predetermined range from an end portion on a side where a sensing part is disposed, wherein the protective layer includes: a first layer disposed on two main surfaces of the element base; a second layer disposed to cover the end portion and four side surfaces of the element base including the two main surfaces on which the first layer is disposed; and a third layer disposed to cover the second layer, and having a lower porosity than the second layer, the first layer has a porosity of 40% or more, and L1?L2 and L1?L3 where L1, L2, and L3 are extension lengths of the first layer, the second layer, and the third layer, respectively, from an end surface of the element base in a longitudinal direction of the element base.

Abstract: A sensor element includes: an element base including a gas distribution part communicating from a gas inlet; and a leading-end protective layer including an inner layer covering an end portion and four side surfaces of the element base and an outer layer covering the inner layer and having a lower porosity than the inner layer, and a total thickness representative value, defined as an average of total thicknesses of the protective layer at a plurality of positions including a starting point, an intermediate position, and an innermost end of the gas distribution part, is 250 ?m or more, and a film thickness variation degree, defined as a ratio of a difference between a maximum value and a minimum value of the total thicknesses with respect to the total thickness representative value when the value is based at 100, is 20 or less.

Abstract: A component includes a film containing polycrystalline yttrium oxide. In an X-ray diffraction pattern of the film, a ratio Im/Ic of a maximum intensity Im of a peak attributed to monoclinic yttrium oxide to a maximum intensity Ic of a peak attributed to cubic yttrium oxide satisfies an expression: 0?Im/Ic?0.002.

Abstract: An aluminum nitride film includes a polycrystalline aluminum nitride. A withstand voltage of the aluminum nitride film is 100 kV/mm or more.

Abstract: A component includes a film containing polycrystalline yttrium oxide. In an X-ray diffraction pattern of the film, a ratio Im/Ic of a maximum intensity Im of a peak attributed to monoclinic yttrium oxide to a maximum intensity Ic of a peak attributed to cubic yttrium oxide satisfies an expression: 0?Im/Ic?0.002.

Abstract: A sensor element includes: an inner protective layer having a porosity of 30% to 65% on two main surfaces; an intermediate protective layer having a porosity of 25% to 80%, which is equal to or smaller than the porosity of the inner layer; and an outer protective layer surrounding an element base on an outermost periphery on the one end portion of the element, and having a porosity of 15% to 30%, which is smaller than the porosity of the intermediate layer, wherein these layers are laminated in this order at least in a range in which the at least one inner chamber is provided in the element base, the outer is in contact with the inner layer in a range in which the at least one inner chamber is not provided, and a difference of porosity between the inner layer and the outer layer is 10% to 50%.

Abstract: A sensor element includes: an inner protective layer having a porosity of 30% to 65% on two main surfaces; an intermediate protective layer, at least a part of which has contact with the inner layer, and having a porosity of 25% to 80%, which is equal to or smaller than the porosity of the inner layer; and an outer protective layer surrounding an element base on an outermost periphery on the one end portion of the sensor element, having contact with the intermediate and the inner layer, having contact with a leading end surface of the element base or the intermediate layer on the leading end surface, and having a porosity of 15% to 30%, which is smaller than the porosity of the intermediate layer, wherein a difference of porosity between the inner and the outer layer is 10% to 50%.

Abstract: A plasma processing device member according to the disclosure includes a base material and a film formed of a rare-earth element oxide, or a rare-earth element fluoride, or a rare-earth element oxyfluoride, or a rare-earth element nitride, the film being disposed on at least part of the base material. The film includes a surface to be exposed to plasma, the surface having an arithmetic mean roughness Ra of 0.01 ?m or more and 0.1 ?m or less, the surface being provided with a plurality of pores, and a value obtained by subtracting an average equivalent circle diameter of the pores from an average distance between centroids of adjacent pores is 28 ?m or more and 48 ?m or less. A plasma processing device according to the disclosure includes the plasma processing device member described above.

Abstract: A plasma processing device member according to the disclosure includes a base material and a film formed of an oxide, or fluoride, or oxyfluoride, or nitride of a rare-earth element, the film being disposed on at least part of the base material, the film including a surface to be exposed to plasma, the surface having an area occupancy of open pores of 8% by area or more, and an average diameter of open pores of 8 ?m or less.

Abstract: A sensor element includes an element body having an elongate rectangular parallelepiped shape and including solid electrolyte layers with oxygen ion conductivity, an outer pump electrode disposed on a first surface of the element body, and a protective layer covering at least a part of a second surface of the element body on a side opposite to the first surface and including one or more exposed spaces (a lower space) to which the second surface is exposed.

Abstract: A member for use in a plasma processing device of the disclosure includes a base material and a film containing yttrium oxide as a main component on the base material. An area occupancy of closed pores of the film is 0.2 area % or less, and a full width at half maximum of a diffraction peak on a (222) plane of yttrium oxide obtained by X-ray diffraction of the film is 0.25° or less. A plasma processing device according to the disclosure includes the member for use in a plasma processing device.

Abstract: A member for use in a plasma processing device of the disclosure includes a base material, and a film of an oxide of a rare earth element on at least a part of the base material. A coefficient of variation of thickness of the film is 0.04 or less. A plasma processing device of the disclosure includes the member for use in a plasma processing device. In the member for use in a plasma processing device according to the disclosure, variation in film thickness is small.

Abstract: A sensor element includes an element body having an elongate rectangular parallelepiped shape and including solid electrolyte layers with oxygen ion conductivity, an outer pump electrode disposed on a first surface of the element body, and a protective layer covering at least a part of the first surface of the element body and including one or more exposed spaces (an upper space) to which the first surface is exposed.

Abstract: A sensor element includes an element body having an elongate rectangular parallelepiped shape and including solid electrolyte layers with oxygen ion conductivity, an outer pump electrode disposed on a first surface of the element body, and a protective layer covering at least a part of the first surface of the element body and including one or more spaces (an upper space) that are present apart from the first surface in a direction perpendicular to the first surface.

Abstract: A method of measuring adhesive strength between an element body and a porous protection layer that are included in a sensor element includes (a) a step of holding a portion of the element body where the porous protection layer is absent with an elastic force exerted by a holding jig, and placing a peeling jig at a position between the porous protection layer and the holding jig in the longitudinal direction such that the element body is allowed to move in the longitudinal direction while the porous protection layer is prevented from moving in the longitudinal direction toward the holding jig; and (b) a step of moving, after the step (a), the peeling jig pushes the porous protection layer in the longitudinal direction, and measuring the adhesive strength of the porous protection layer.

Abstract: A sensor element for a gas sensor includes: an element base being a ceramic structure including a sensing part to sense a gas component to be measured; and a leading-end protective layer being a porous layer to surround a predetermined range from a leading end portion on a side of the sensing part of the element base. The leading-end protective layer protrudes at a first end portion thereof opposite to a portion surrounding the element base in a longitudinal direction of the element base. A/B?1.1 where A is maximum thickness of the leading-end protective layer, and B is thickness of the leading-end protective layer in a base portion that does not protrude.

Abstract: A gas sensor element includes: an element base being a ceramic structure including a sensing part to sense a gas component to be measured; and a leading-end protective layer being a porous layer disposed around an outer periphery of the element base in a predetermined range from an end portion of the element base on a side of the sensing part. A near-surface portion of the leading-end protective layer near a surface thereof has a porosity of 15% to 30%, and has a value of surface roughness Ra of 3 ?m to 35 ?m.

Abstract: A gas sensor element includes: an element base being a ceramic structure including a sensing part; and a leading-end protective layer being a porous layer disposed around an outer periphery of the element base in a predetermined range on a side of the sensing part. The leading-end protective layer includes: a first layer disposed at least on two main surfaces of the element base; a second layer disposed to cover the end portion and four side surfaces of the element base including the two main surfaces; and a third layer disposed to cover the second layer. The second layer has a porosity of 30% to 80%, and has a thickness of 30 to 50 times thickness of the first layer, and the third layer has a porosity of 15% to 30%, and has a thickness of 5 to 10 times the thickness of the first layer.

Abstract: A sensor element includes: an element base including: a ceramic body made of an oxygen-ion conductive solid electrolyte, and having an inlet at one end portion thereof; at least one internal chamber located inside the ceramic body, and communicating with the gas inlet; and an electrochemical pump cell including an outer electrode, an inner electrode facing the chamber, and a solid electrolyte therebetween, and a porous leading-end protective layer covering a leading end surface and four side surfaces in a predetermined range of the element base on the one end portion, wherein the protective layer has an extension extending into the gas inlet and fixed to an inner wall surface of the ceramic body demarcating the gas inlet, and a gap communicating with the gas inlet is located in the protective layer, with demarcated by a portion of the protective layer continuous with the extension.