Pattern fortification for hdd bit patterned media pattern transfer

A method of patterning a substrate, comprising:

• forming a first layer comprising carbon on a magnetically active surface of the substrate;
• forming a titanium nitride film on the first layer by a PVD process at a temperature less than about 200° C.;
• forming a second layer over the titanium nitride film;
• physically imprinting second layer to form a pattern;
• forming a third layer over the second layer;
• etching the third layer using halogen chemistry;
• removing a portion of the second layer by applying an oxygen plasma to the substrate;
• patterning the titanium nitride film by exposing the substrate to a remote plasma comprising Cl2 and O2 to form protected domains of the magnetically active surface separated by unprotected domains of the magnetically active surface;
• forming a coating over the patterned metal nitride film, wherein the coating comprises tungsten;
• altering a magnetic property of the unprotected domains of the magnetically active surface by exposing the substrate to a plasma;
• and
• removing the titanium nitride film.