Method and apparatus for magnetic recording head having a waveguide

A waveguide formation method for a heat assisted magnetic recording slider of a disk drive, comprising:

• depositing a layer of waveguide material onto a substrate;
• depositing a layer of a non-crystalline solid material onto the waveguide material, wherein the non-crystalline solid material comprises Al2O3;
• depositing a layer of photoresist onto the non-crystalline solid material;
• exposing the photoresist to produce a waveguide pattern that includes a waveguide pattern from the non-crystalline solid material;
• removing the photoresist material not associated with the waveguide pattern to form a waveguide pattern having a first line edge roughness;
• removing an exposed portion of the non-crystalline solid material to form the hard mask for the waveguide pattern in the non-crystalline solid material, the non-crystalline solid material having a second line edge roughness which is substantially equal to the first line edge roughness;
• and
• removing the waveguide material not covered by the hard mask to form a waveguide having sidewalls which having a line edge roughness which is substantially equal to the first line edge roughness.

A waveguide formation method for a heat assisted magnetic recording slider of a disk drive, comprising:

• depositing a layer of waveguide material onto a substrate;
• depositing a layer of a hard mask material onto the waveguide material, wherein the hard mask material comprises Al2O3;
• depositing a layer of photoresist onto the hard mask material;
• exposing the photoresist to produce a hard mask pattern that includes a waveguide pattern;
• stripping the photoresist material leaving the hard mask pattern having a first line edge roughness (LER) in a range of 0.1-3.0 σ deviation of a line edge from a straight line;
• and
• removing the waveguide material not covered by the hard mask pattern to form a waveguide having sidewalls which having a second line edge roughness which is substantially the same as the first line edge roughness associated with the hard mask pattern.