Porogens, porogenated precursors and methods for using the same to provide porous organosilica glass films with low dielectric constants

A chemical vapor deposition method for producing an organosilica glass film represented by the formula SivOwCxHyFz, where v+w+x+y+z=100%, v is from 10 to 35 atomic %, w is from 10 to 65 atomic %, x is from 5 to 30 atomic %, y is from 10 to 50 atomic % and z is from 0 to 15 atomic %, said method comprising:

• providing a substrate within a vacuum chamber;
• introducing into the vacuum chamber gaseous reagents including at least one precursor gas selected from the group consisting of a organosilane and an organosiloxane, wherein the at least one precursor gas contains at least one porogen bonded thereto;
• applying energy to the gaseous reagents in the vacuum chamber to induce reaction of the gaseous reagents to deposit a preliminary film on the substrate, wherein the preliminary film contains the at least one porogen and a first quantity of methyl groups bonded to silicon atoms;
• and
• removing from the preliminary film at least a portion of the at least one porogen to provide the porous film with pores and a dielectric constant less than 2.6, wherein the porous film contains a second quantity of methyl groups bonded to silicon atoms, and the second quantity is more than 50% of the first quantity.