Method for manufacturing a hosting structure of nanometric elements comprising the steps of depositing on an upper surface of a substrate, of a first material, a block-seed having at least one side wall. Depositing on at least one portion of sad surface and on the block-seed a first layer, of predetermined thickness of a second material, and subsequently selectively and anisotropically etching it to form a spacer-seed adjacent to the side wall. The cycle of deposition and selective etching steps of a predetermined material are repeated n times (n.gtoreq.2), with at least one spacer formed in each cycle. This predetermined material is different for each pair of consecutive depositions. The above n steps provides at least one multilayer body. Further selective etching removes every other spacers to provide a plurality of nanometric hosting seats, which forms contact terminals for a plurality of molecular transistors hosted in said hosting seats.