Flowable low-k dielectric gapfill treatment

A method of filling a trench, the method comprising:

• transferring a patterned substrate comprising the trench into a substrate processing region of a substrate processing chamber;
• flowing an oxygen-containing precursor into a remote plasma region while igniting a remote plasma to form a radical-oxygen precursor;
• flowing a silicon-and-carbon-containing precursor into the substrate processing region without first passing the silicon-and-carbon-containing precursor through any plasma;
• flowing the radical-oxygen precursor into the substrate processing region;
• combining the silicon-and-carbon-containing precursor and the radical-oxygen precursor in the substrate processing region to form a low-k dielectric film on the patterned substrate, wherein a portion of the low-k dielectric film deposits on the patterned substrate and flows along a surface of the patterned substrate during formation of the low-k dielectric film to fill the trench;
• and
• flowing a hydrogen-and-nitrogen-containing precursor into the substrate processing region to treat the patterned substrate and form a treated low-k dielectric film.

A method of filling a trench, the method comprising:

• transferring a patterned substrate comprising the trench into a substrate processing region of a substrate processing chamber;
• flowing molecular oxygen into a remote plasma region while igniting a remote plasma to form plasma effluents;
• flowing the plasma effluents into the substrate processing region through through-holes in a showerhead disposed and forming a border between the remote plasma region and the substrate processing region;
• flowing a silicon-and-carbon-containing precursor into the substrate processing region without first passing the silicon-and-carbon-containing precursor through a plasma, wherein the silicon-and-carbon-containing precursor has a Si—O:Si ratio of less than 3;
• combining the silicon-and-carbon-containing precursor and the plasma effluents in the substrate processing region to form a low-k dielectric film on the patterned substrate;
• flowing ammonia into the substrate processing region to treat the patterned substrate and form a treated low-k dielectric film, wherein the substrate processing region is devoid of plasma;
• and
• curing the treated low-k dielectric film by exposure to ultraviolet light.