Patent ID: 7727907

Claim:
A manufacturing method of a semiconductor device, comprising: a step of forming a dielectric thin film in which a plurality of pores are arranged around a skeleton mainly made of a Si—O bond, on a surface of a semiconductor substrate on which a desired element region is formed; a step of applying patterning on a surface of the dielectric thin film through a mask; and a step of bringing a gas containing at least one kind of tetramethylcyclotetrasiloxane (TMCTS), hexamethyldisilazane (HMDS) and trimethylchlorosilane (TMCS) molecules into contact with the patterned surface of the dielectric thin film wherein the patterning step comprises: a step of forming a hard mask on the surface of the dielectric thin film obtained in the film-forming step; a step of peeling and removing a resist for the patterning of the hard mask before the step of etching the dielectric thin film; a step of bringing a gas containing at least one kind of tetramethylcyclotetrasiloxane (TMCTS), hexamethyldisilazane (HMDS), and trimethylchlorosilane (TMCS) molecules into contact after the step of peeling and removing and before the step of etching the dielectric thin film; and a step of etching the dielectric thin film through the hard mask.