Film forming method, article manufacturing method, supply device, film forming apparatus, and substrate

A film forming method of forming a film on a substrate, wherein

• the substrate includes a region including a first concave portion and a second concave portion, and
• the first concave portion has a width larger than that of the second concave portion,
• the film forming method comprising:
• selectively supplying a first material into the first concave portion and curing the first material;
• and
• supplying a second material onto the region including the first concave portion and the second concave portion and curing the second material, such that the second concave portion is filled with the second material and a planarization film of the second material is formed over all of the region,
• each of the first material and the second material containing a polymerizable compound and a polymerization initiator and being a curable composition whose volume changes by being cured, and
• in the selectively supplying, the first material is supplied into the first concave portion at an amount such that a height of a surface of the cured first material is higher than a height of an edge of the first concave portion.