Writer pole formation

Patent metadata

Field	Value
Publication number	US-2016099019-A1
Application number	US-201414503589-A
Country	US
Kind code	A1
Filing date	Oct 1, 2014
Priority date	Oct 1, 2014
Publication date	Apr 7, 2016
Grant date	—

Abstract

Implementations disclosed herein provide a method of reducing the topography at the alignment and overlay marks area during the writer pole photolithography process in order to reduce the wafer scale variation and reduce the writer pole photolithography process rework rate. In one implementation, an intermediate stage of a wafer for writer pole formation is generated by removing a part of at least one metallic writer pole layer on top of an intermediate stage writer pole wafer to form a recovery trench, depositing an optically transparent material on top of the wafer, wherein the thickness of the optically transparent material is higher than a target recovery trench topography, forming a photoresist pattern on top of the optically transparent material over the recovery trench, etching the optically transparent material, and removing the photoresist pattern and at least part of the remaining optically transparent material.

First claim

What is claimed is:

1 . A method comprising:
removing a part of at least one metallic writer pole layer on top of an intermediate stage writer pole wafer to form a recovery trench; depositing an optically transparent material on top of the wafer, wherein the thickness of the optically transparent material is higher than a target recovery trench topography; forming a photoresist pattern on top of the optically transparent material over the recovery trench; etching the optically transparent material; and removing the photoresist pattern and at least part of the remaining optically transparent material.

2 . The method of claim 1 , wherein removing multiple metallic writer pole layers includes performing milling.

3 . The method of claim 1 , wherein the recovery trench is located over an alignment mark of the wafer.

4 . The method of claim 1 , wherein the recovery trench is located over an overlay mark of the wafer.

5 . The method of claim 1 , wherein forming the photoresist pattern includes performing photolithography.

6 . The method of claim 1 , wherein the optically transparent material is alumina.

7 . The method of claim 1 , wherein etching the optically transparent material is a wet etching process.

8 . The method of claim 1 , wherein etching the optically transparent material includes etching optically transparent material on the top of the wafer on sides of the photoresist pattern generated over the recovery trench.

9 . The method of claim 1 , wherein depositing the optically transparent material is performed by sputtering.

10 . The method of claim 1 , wherein depositing the optically transparent material is performed by plasma enhanced vapor deposition.

11 . The method of claim 1 , wherein depositing the optically transparent material is performed by atomic layer deposition.

12 . The method of claim 1 , wherein removing part of the deposited optically transparent material with a chemical mechanical process.

13 . The method of claim 1 , wherein removing at least part of the optically transparent material comprises removing at least part of the optically transparent material until the top surface of the optically transparent material is substantially at asame level as the top level of the remainder of the wafer.

14 . A method of forming an intermediate stage writer pole wafer comprising:
removing a part of at least one metallic writer pole layer on top of the writer pole wafer to form a recovery trench; depositing alumina on top of the wafer filling the recovery trench, wherein a thickness of the alumina is higher than a target recovery trench topography; forming a photoresist pattern on top of the alumina over the recovery trench; wet etching the alumina; and chemically removing the photoresist; and removing at least part of a remaining part of the alumina.

15 . The method of claim 14 , wherein the recovery trench is located over an overlay and an alignment of the wafer.

16 . A wafer, comprising:
a substrate, writer pole material deposited on top of the substrate; and a recovery trench positioned in between writer pole material and above the substrate; and an optically transparent material backfilled into the recovery trench.

17 . The wafer of claim 16 , further comprising an alignment mark on bottom of the substrate.

18 . The wafer of claim 16 , further comprising an overlay mark on bottom of the substrate.

19 . The wafer of claim 16 , wherein the top of the optically transparent material is etched so as to be substantially aligned to the top surface of the writer pole metal.

20 . The wafer of claim 16 , wherein the optically transparent material is alumina.

Assignees

• Seagate Technology Llc

Inventors

• Liu Yi
• Bowser Aaron M
• Yu Dan
• Zhang Xiaohong

Classifications

• H10W46/301

  for alignment · CPC title

• G11B5/855 Primary

  Coating only part of a support with a magnetic layer · CPC title

• G03F9/708

  Mark formation · CPC title

• C23F1/02

  Local etching · CPC title

• C09K13/00

  Etching, surface-brightening or pickling compositions (for glass C03C15/00, {C03C25/66; for mortars, concrete, artificial or natural stone or ceramics C04B41/5338}; for metallic material C23F, C23G1/00, C25F1/00; {for semi-conductors H10P52/40}) · CPC title