Abstract: Provided is a method for forming a low dielectric constant film on a substrate placed in a processing chamber inside a processing container. The method includes: generating plasma using microwaves by supplying at least a noble gas to a plasma generation chamber, which is formed above the processing chamber inside the processing container; forming a low dielectric constant film on the substrate by supplying particles from the plasma generation chamber to the processing chamber and supplying a precursor gas to the processing chamber through a shield unit provided between the plasma generation chamber and the processing chamber, the shield unit having a plurality of openings configured to communicate the plasma generation chamber with the processing chamber, and having a shielding property against ultraviolet light; and then, performing a heat treatment on the substrate.