Patent ID: 8790527
Filing Date: 2014-07-29
Classification: B29D

Abstract:
1. A method for providing a plurality of waveguide structures for an energy assisted magnetic recording (EAMR) transducer, the plurality of waveguide structures having a plurality of widths, the method comprising: providing at least one waveguide layer, the at least one waveguide layer including a waveguide core layer; providing at least one mask structure having a pattern on the at least one waveguide layer, the at least one mask structure including a planarization stop layer, a planarization assist layer on the planarization stop layer, and a hard mask layer on the planarization assist layer, the planarization assist layer having a low density, the at least one mask structure corresponding to the plurality of waveguide structures; transferring the pattern of the at least one mask structure to the at least one waveguide layer, a remaining portion of the at least one waveguide layer forming at least part of the plurality of waveguide structures; providing at least one optical material covering the at least one waveguide layer and a remaining portion of the at least one mask structure, the at least one optical material having a density, the low density of the planarization assist layer being not more than half of the density of the at least one optical material; and performing a planarization configured to remove at least a portion of the at least one optical material such that the hard mask is removed from the plurality of waveguide structures having the plurality of widths without damaging any of the plurality of waveguide structures.