SYSTEM, METHOD AND APPARATUS FOR FABRICATING A C-APERTURE OR E-ANTENNA PLASMONIC NEAR FIELD SOURCE FOR THERMAL ASSISTED RECORDING APPLICATIONS

• US 20100163521A1
• Filed: 12/30/2008
• Published: 07/01/2010
• Est. Priority Date: 12/30/2008
• Status: Active Grant

• Current Assignee: Western Digital Technologies Incorporated (Western Digital Corporation)
• Original Assignee: Hitachi Global Storage Technologies Netherlands BV (Western Digital Corporation)
• Inventors: Katine, Jordan Asher, Stipe, Barry Cushing, Boone, Thomas Dudley JR., Balamane, Hamid
• Granted Patent: US 8,092,704 B2
• Time in Patent Office: Days
• US Class Current: 216/22
• 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) 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;

(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 60 nm of SiO₂ and the base layer is 300 nm of 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 step (c) comprises Cr liftoff the pair of parallel features is formed from Cr in rectangular shapes, and the gap is approximately 30 nm.

5. A method according to claim 4, 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 approximately 120 nm of 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 structures and defining an air bearing surface (ABS) edge by lapping the structure.

16. A method according to claim 1, wherein step (h) comprises depositing approximately 120 nm of Au on the structure, and 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 of approximately 30 nm;

(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 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.

12. A method according to claim 11, wherein step (a) comprises depositing the insulator layer as 60 nm of SiO₂ and the base layer is 300 nm of 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 (o 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.