Self-assembled block copolymer films having two or more blocks are manufactured by distributing a solution containing at least one block copolymer onto the substrate so as to partially coat a substrate surface, obtaining an intermediate product. A block copolymer is self-assembled by heating the intermediate product. The self-assembling step includes Rapid Thermal Processing, which is performed by heating the intermediate product up to a first target temperature, ranging from a glass transition temperature to an order-disorder transition temperature of the block copolymer, through a temperature rising ramp having a rate of temperature change not lower than 5° C./second; maintaining the intermediate product at the target temperature for a time interval not longer than 60 minutes, whereby a sample is obtained on the surface of which a self-assembled film of the block copolymer has been made; and cooling the sample down to the ambient temperature through a temperature descending ramp.