PROBLEM TO BE SOLVED: To provide an apparatus capable of forming an alignment layer having high density of organic molecules.SOLUTION: A surface treatment apparatus of the present invention performs: a first step of bonding first organic molecules having three or four functional groups each having the same alkoxy groups and a hydroxyl group on a surface of a substrate together in a decompressed environment; a second step of bonding the alkoxy groups of the first organic molecules bound to the surface and water molecules in the decompressed environment thereby causing the alkoxy groups of the first organic molecules to be hydroxyl groups; and a third step of bonding second organic molecules having one functional group having a function different from that of the first organic molecules and the other two or three functional groups being the alkoxy groups and the hydroxyl groups generated in the second step together in the decompressed environment. The surface treatment apparatus includes: a surface treatment ca
