System, method and apparatus for fabricating a C-aperture or E-antenna plasmonic near field source for thermal assisted recording applications

• US 8,486,289 B2
• Filed: 11/29/2011
• Issued: 07/16/2013
• Est. Priority Date: 12/30/2008
• Status: Active Grant

• Current Assignee: Western Digital Technologies Incorporated (Western Digital Corporation)
• Original Assignee: HGST Netherlands B.V. (Western Digital Corporation)
• Inventors: Balamane, Hamid, Boone, Thomas Dudley, Katine, Jordan Asher, Stipe, Barry Cushing
• Primary Examiner(s): Tran, Binh X
• Assistant Examiner(s): PHAM, THOMAS T
• Application Number:
  US13/306,582
• Publication Number:
  US 20120070784A1
• Time in Patent Office: 595 Days
• Field of Search: 216/57
• US Class Current: 216/57
• CPC Class Codes: G11B 2005/0021 Thermally assisted recording using an auxiliary energy source for heating the recording layer locally to assist the magnetization reversal
• CPC Class Codes: G11B 5/314 where the layers are extra layers normally not provided in the transducing structure, e.g. optical layers G11B5/3196 takes precedence
• CPC Class Codes: G11B 5/3163 Fabrication methods or processes specially adapted for a particular head structure, e.g. using base layers for electroplating, using functional layers for masking, using energy or particle beams for shaping the structure or modifying the properties of the basic layers
• CPC Class Codes: G11B 5/6088 Optical waveguide in or on flying head

Abstract

A method of fabricating a c-aperture or E-antenna plasmonic near field source for thermal assisted recording applications in hard disk drives is disclosed. A c-aperture or E-antenna is built for recording head applications. The technique employs e-beam lithography, partial reactive ion etching and metal refill to build the c-apertures. This process strategy has the advantage over other techniques in the self-alignment of the c-aperture notch to the c-aperture internal diameter, the small number of process steps required, and the precise and consistent shape of the c-aperture notch itself.

Claims

1. A method of fabricating a plasmonic near field source for thermal assisted recording applications in hard disk drives, the method comprising:

(a) depositing an insulator layer on a base layer;

(b) applying an e-beam resist layer on the insulator layer;

(c) depositing a hard mask layer on the e-beam resist layer, and performing e-beam lithography and liftoff on the e-beam resist layer to form a pair of parallel hard mask features separated by a gap;

(d) reactive ion etching (RIE) the insulator layer to form a notch therein located below the gap;

(e) performing e-beam lithography and liftoff to add a second hard mask over the gap;

(f) reactive ion etching the pair of parallel hard mask features to define edges of a structure in the insulator layer;

(g) wet etching the structure to remove extraneous hard mask material from the insulator layer;

(h) depositing a conductive layer on the structure; and

then

(i) fabricating a throat of a c-aperture in the structure.

2. A method according to claim 1, wherein step (a) comprises depositing the insulator layer as SiO₂ and the base layer is CoFe.

3. A method according to claim 1, wherein step (b) comprises applying polymethylmethacrylate (PMMA) on the insulator layer.

4. A method according to claim 1, wherein the liftoff on the e-beam resist layer of step (c) comprises plating Cr into openings in the e-beam resist layer to form the pair of parallel hard mask features from Cr separated by the gap, and lifting off the e-beam resist layer.

5. A method according to claim 1, wherein step (e) comprises Cr liftoff wherein a formed Cr feature completely covers the notch, but is narrower than outer edges of the pair of parallel features.

6. A method according to claim 1, wherein step (d) comprises using CF₄ to reduce a thickness of the insulator layer outside the pair of parallel features and in the gap.

7. A method according to claim 1, wherein step (f) enables the notch to be exactly centered between the edges of the structure.

8. A method according to claim 1, wherein step (g) comprises wet Cr etching, such that only the notched insulator layer and the base layer remain.

9. A method according to claim 1, wherein step (h) comprises depositing Au on the structure.

10. A method according to claim 1, wherein step (i) comprises defining a back wall of the c-aperture and a waveguide trackwidth by photoresist processes on the structure, and defining an air bearing surface (ABS) edge by lapping the structure.

11. A method of fabricating a plasmonic near field source for thermal assisted recording applications in hard disk drives, the method comprising:

(a) depositing an insulator layer on a base layer;

(b) applying an e-beam resist layer on the insulator layer;

(c) performing e-beam lithography and Cr liftoff on the e-beam resist layer to form a pair of parallel hard mask features from Cr in rectangular shapes separated by a gap;

(d) reactive ion etching (RIE) the insulator layer to form a notch therein located below the gap;

(e) performing e-beam lithography and Cr liftoff to add a second hard mask over the gap, wherein a formed Cr feature completely covers the notch, but is narrower than outer edges of the pair of parallel hard mask features;

(f) reactive ion etching the insulator layer around the pair of parallel hard mask features to define edges of a structure;

(g) wet etching the structure to remove extraneous hard mask material from the insulator layer;

(h) depositing a conductive layer on the structure; and

then

(i) fabricating a throat of a c-aperture in the structure by defining a back wall of the c-aperture and a waveguide trackwidth by photoresist processes on the structure, and defining an air bearing surface (ABS) edge by lapping the structure.

12. A method according to claim 11, wherein step (a) comprises depositing the insulator layer as SiO₂ and the base layer is CoFe, and step (b) comprises applying polymethylmethacrylate (PMMA) on the insulator layer.

13. A method according to claim 11, wherein step (d) comprises using CF₄ to reduce a thickness of the insulator layer outside the pair of parallel features and in the gap.

14. A method according to claim 11, wherein step (f) enables the notch to be exactly centered between the edges of the structure.

15. A method according to claim 11, wherein step (g) comprises wet Cr etching, such that only the notched insulator layer and the base layer remain.

16. A method according to claim 11, wherein step (h) comprises depositing Au on the structure.