Abstract: The plasma-resistant coating film according to the present invention is formed on a substrate, including crystalline Y2O3 particles having an average particle diameter of 0.5 ?m to 5.0 ?m in a SiO2 film, in which a film density of the plasma-resistant coating film is 90% or more, the film density being obtained by performing image analysis of a cross section of the film with an electron scanning microscope and by using the following expression (1), a size of pores in the film is 5 ?m or less in terms of diameter, and a peeling rate of the film from the substrate measured by performing a cross-cut test is 5% or less. Film density (%)=[(S1?S2)/S1]×100 (1). However, in the expression (1), S1 is an area of the film and S2 is an area of a pore portion in the film.

Abstract: A piezoelectric film contains iron-containing potassium sodium niobate represented by General Formula (1) and granular crystal particles having an average aspect ratio of 3 or less. (KxNa1-x)a(FeyNbz)O3??(1) In Formula (1), x represents a number satisfying 0<x<1, a represents a number satisfying 0.90<a?1, and y and z represent numbers satisfying y+z=1 and 0.006?y/z?0.04.

Abstract: This liquid composition for forming a KNN film includes an organic metal compound including an organic potassium compound, an organic sodium compound, and an organic niobium compound, and a solvent. In this liquid composition for forming a KNN film, the organic potassium compound and the sodium compound are each metal salts of a carboxylic acid represented by General Formula CnH2n+1COOH (here, 4?n?8), the organic niobium compound is a niobium alkoxide or a metal salt of a carboxylic acid represented by General Formula CnH2n+1COOH (here, 4?n?8), and a main solvent is a carboxylic acid represented by General Formula CnH2n+1COOH (here, 4?n?8) and is included in an amount of 50% by mass to 90% by mass with respect to 100% by mass of the liquid composition for forming a KNN film.