To improve the efficiency of a coating liquid to be used by improving a process in which the coating liquid is stuck on the surface of a substrate in spin coating.

An apparatus for forming a thin film has a spin unit 10 which holds the substrate 1 and rotates it at a desired rotational speed and an ink-jet heat 20 located above the unit 10. The heat 20 has small-diameter nozzles 21, which are arranged at constant intervals in the radium direction of the substrate. In the coating liquid sticking process, while the substrate is rotated slowly, liquid drops 22 are discharged from the nozzles 21 in required timing to be stuck on the surface of the substrate in an optimum pattern. The substrate is rotated at a high speed in a thin film forming process, the adherent liquid drops 23 is spread on the surface of the substrate by centrifugal force, and the excess coating liquid is scattered to be removed. An ink-jet heat 20 is preferably piezo-type which can discharge a liquid with viscosity as high as 10 Pa.s.