Abstract: A method of supplying a liquid dispersive medium of fine particles onto the surface of a substrate having a flat surface, forming a liquid thin film and controlling the liquid thickness of the liquid dispersive medium through evaporation, for example, thereby assembling the particles in a two-dimensional manner. By controlling the liquid thickness of the liquid dispersive medium of the particles, it is possible to cause rapid two-dimensional assembly of the particles, and in addition, to control the order of particle size in the assembly. Fixing of the assembly permits the formation of a film structure.