Method for making a perpendicular magnetic recording write head with write pole having thin side gaps and thicker leading gap

Patent metadata

Field	Value
Publication number	US-9805747-B2
Application number	US-201514827705-A
Country	US
Kind code	B2
Filing date	Aug 17, 2015
Priority date	Aug 17, 2015
Publication date	Oct 31, 2017
Grant date	Oct 31, 2017

Abstract

Ionized physical vapor deposition (IPVD) is used to form a magnetic recording disk drive write head main pole with thin side gap layers and a thicker leading gap layer. A metal or metal alloy is formed by IPVD in a trench with a bottom and outwardly sloping sidewalls. An optional Ru seed layer is deposited on the metal or metal alloy. This is followed by atomic layer deposition (ALD) of a Ru smoothing layer. If the IPVD results in metal or metal alloy side gap layers with a rough surface, the ALD process is modified, resulting in a smooth Ru smoothing layer that does not replicate the rough surface of the side gap layers.

First claim

What is claimed is:

1. A method for depositing a layer of material in a substrate having a trench with a bottom and outwardly sloped sidewalls comprising:
depositing into the trench, by ionized physical vapor deposition, material selected from a metal and a metal alloy to form a bottom layer of said material and sidewall layers of said material, wherein said sidewall layers are thinner than said bottom layer;
depositing a seed layer of ruthenium (Ru) on said bottom layer and said sidewall layers; and
depositing a smoothing layer of Ru on said Ru seed layer by atomic layer deposition using RuO 4 and H 2 , wherein the RuO 4 acts as a precursor that reduces to RuO 2 on said Ru seed layer and the H 2 acts to reduce RuO 2 to Ru.

2. The method of claim 1 wherein said material is selected from a NiNb alloy, a NiTa alloy and a NiCr alloy.

3. The method of claim 1 wherein the thickness of said bottom layer is at least 1.5 times as thick as the thickness of said sidewall layers.

4. The method of claim 1 wherein said sidewall layers have a surface substantially rougher than the surface of said bottom layer, wherein the Ru seed layer substantially replicates the surface of said sidewall layers, and further comprising, after the RuO 2 has formed on the Ru seed layer, continuing to introduce RuO 4 .

5. The method of claim 1 wherein said sidewall layers have a surface substantially rougher than the surface of said bottom layer, wherein the Ru seed layer substantially replicates the surface of said sidewall layers, and further comprising, after the RuO 2 has formed on the Ru seed layer, delaying the introduction of H 2 .

6. The method of claim 1 further comprising depositing a metallic pole seed layer comprising Co and Fe on the Ru smoothing layer and electroplating a ferromagnetic pole layer comprising Co and Fe on the pole seed layer.

7. A method for forming a main pole of a magnetic recording disk drive write head comprising:
providing a substrate having a trench with a bottom and outwardly sloped sidewalls;
depositing into the trench, by ionized physical vapor deposition, material selected from a nonmagnetic metal and a nonmagnetic metal alloy to form a bottom layer of said material and sidewall layers of said material, said sidewall layers having a thickness and said bottom layer is having a thickness at least 1.5 times the thickness of said sidewall layers;
depositing a seed layer of ruthenium (Ru) on said bottom layer and said sidewall layers;
depositing a smoothing layer of Ru on said Ru seed layer by atomic layer deposition using RuO 4 and H 2 , wherein the RuO 4 acts as a precursor that reduces to RuO 2 on said Ru seed layer and the H 2 acts to reduce RuO 2 to Ru;
depositing a metallic pole seed layer comprising Co and Fe on the Ru smoothing layer; and
electroplating a ferromagnetic pole layer comprising Co and Fe on the pole seed layer.

8. The method of claim 7 wherein said material is selected from a NiNb alloy, a NiTa alloy and a NiCr alloy.

9. The method of claim 7 wherein said sidewall layers have a surface substantially rougher than the surface of said bottom layer, wherein the Ru seed layer substantially replicates the surface of said sidewall layers, and further comprising, after the RuO 2 has formed on the Ru seed layer, continuing to introduce RuO 4 .

10. The method of claim 7 wherein said sidewall layers have a surface substantially rougher than the surface of said bottom layer, wherein the Ru seed layer substantially replicates the surface of said sidewall layers, and further comprising, after the RuO 2 has formed on the Ru seed layer, delaying the introduction of H 2 .

11. The method of claim 7 wherein providing a substrate comprises providing a substrate formed of ferromagnetic material selected from alloys of two or more of Ni, Fe and Co.

12. A method for depositing a layer of material in a substrate having a trench with a bottom and outwardly sloped sidewalls comprising:
depositing into the trench, by ionized physical vapor deposition, material selected from a metal and a metal alloy to form a bottom layer of said material and sidewall layers of said material, wherein said sidewall layers are thinner than said bottom layer;
depositing a smoothing layer of Al 2 O 3 on said bottom layer and said sidewall layers by atomic layer deposition, said Al 2 O 3 smoothing layer having a thickness greater than or equal to 1 nm and less than 5 nm; and
depositing a metallic pole seed layer comprising Co and Fe on the Al 2 O 3 smoothing layer and electroplating a ferromagnetic pole layer comprising Co and Fe on the pole seed layer.

Assignees

• HGST Netherlands BV
• Western Digital Tech Inc

Inventors

• Hixson-Goldsmith April D
• Shi Ning
• Shin Kyusik
• Song Suping
• York Brian R

Classifications

• G11B5/3116

  Shaping of layers, poles or gaps for improving the form of the electrical signal transduced, e.g. for shielding, contour effect, equalizing, side flux fringing, cross talk reduction between heads or between heads and information tracks (G11B5/3113, G11B5/245 take precedence) · CPC title

• G11B5/315

  Shield layers on both sides of the main pole, e.g. in perpendicular magnetic heads · CPC title

• G11B5/232

  Manufacture of gap · CPC title

• G11B5/3163 Primary

  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 title

• G11B5/1278

  specially adapted for magnetisations perpendicular to the surface of the record carrier · CPC title