Patent attributes
A plasma-resistant member that includes a base material and a layer structural component is provided, wherein the layer structural component includes an yttria polycrystalline body, is formed at a surface of the base material, and has plasma resistance; crystallites that are included in the yttria polycrystalline body included in the layer structural component are not bonded to each other via a heterogenous phase; the yttria polycrystalline body included in the layer structural component has a crystal structure including only cubic, or a crystal structure in which cubic and monoclinic coexist; and an average value of a proportion of monoclinic to cubic inside the yttria polycrystalline body included in the layer structural component is greater than 0% and not more than 60%.