Thin-film crystalline structure with surfaces having selected plane orientations

Patent metadata

Field	Value
Publication number	US-12057147-B2
Application number	US-202117511741-A
Country	US
Kind code	B2
Filing date	Oct 27, 2021
Priority date	Nov 20, 2017
Publication date	Aug 6, 2024
Grant date	Aug 6, 2024

Abstract

A method of forming a thin film structure involves performing one or more repetitions to form a template on a wafer. The repetitions include: depositing a layer of a template material to a first thickness T1; and ion beam milling the layer of the template material to remove thickness T2, where T2<T1, resulting in a layer of the template material with thickness T1−T2. The ion beam milling is performed at a channeling angle relative to a deposition plane of the wafer, the channeling angle defined relative to a channeling direction of a crystalline microstructure of the template material. After the repetitions, additional material is deposited on the template to form a final structure. The additional material has a same crystalline microstructure as the template material.

First claim

What is claimed is:

1. A method of forming a thin film structure, comprising:
performing one or more repetitions to form a template on a substrate, the template used to form a structure having a first surface parallel to the substrate and a second surface orthogonal to the first surface, the repetitions comprising:
depositing a layer of a template material to a first thickness T1; and
ion beam milling the layer of the template material to remove thickness T2, where T2<T1, resulting in a layer of the template material with thickness T1−T2, wherein the ion beam milling is at an angle that results in a first majority of crystalline grains at the first surface being oriented at a first plane orientation to have a first atomic packing factor at the first surface and a second majority of crystalline grains at the second surface oriented at a second plane orientation to have a second atomic packing factor; and

depositing additional material on the template to form the structure, the additional material having a same crystalline microstructure as the template material.

2. The method of claim 1 , wherein an average of the first and second atomic packing factors is greater than or equal to 0.70.

3. The method of claim 2 , wherein the average of the first and second atomic packing factors comprises the first and second atomic packing factors are weighted by respective first and second areas of the first and second surfaces.

4. The method of claim 1 , wherein the template material comprises an fcc metal, and wherein the respective first and second plane orientations are one of: {100},{100}; {100},{210}; {211}, {111}; {110},{111}; {111},{211}; {111},{100}; {110},{211}; or {211},{110}.

5. The method of claim 1 , wherein the template material comprises Rh or Ir, and wherein the first and second plane orientations result in respective first and second surface energies of the respective first and second planes, an average of the first and second surface energies being less than or equal to 3.5×10 −4 ergs for Rh or less than or equal to 3.7×10 −4 ergs for Ir.

6. The method of claim 1 , wherein the additional material is different from the template material, and wherein the same microstructure is one of fcc, bcc, and hcp.

7. The method of claim 1 , wherein the repetitions comprise two or more repetitions.

8. The method of claim 7 , wherein T1 and T2 satisfy at least one of:
values of at least one of T1 and T2 are different in at least two of the two or more repetitions; and
a ratio between T1 and T2 is different in at least two of the two or more repetitions.

9. The method of claim 1 , wherein Ne is used as a working gas for the ion beam milling and Ar is used as a neutralizing gas for the ion beam milling.

10. The method of claim 1 , wherein the final structure comprises a component of a recording head.

11. The method of claim 1 , wherein depositing the layer of the template material comprises ion beam deposition and depositing the additional material comprises deposition without ion beam assistance.

12. The method of claim 1 , wherein the substrate comprises a flat surface on which the template is formed, and wherein the ion beam milling the layer of the template material to remove the thickness T2 comprises removing a uniform thickness from the flat surface.

13. A method of forming a thin film structure, comprising:
performing one or more repetitions to form a template on a wafer, the repetitions comprising:
depositing a layer of a template material to a first thickness T1; and
ion beam milling the layer of the template material to remove thickness T2, where T2<T1, resulting in a layer of the template material with thickness T1−T2, wherein the ion beam milling is performed at a channeling angle relative to a deposition plane of the wafer, the channeling angle defined relative to a channeling direction of a crystalline microstructure of the template material; and

depositing additional material on the template to form a final structure, the additional material having a same crystalline microstructure as the template material.

14. The method of claim 13 , wherein the channeling angle is set to a value between a first crystallographic plane aligned with a growth direction of the template material and a second crystallographic plane aligned with the channeling direction.

15. The method of claim 13 , wherein the ion beam milling is performed in two or more passes at two or more different respective angles relative to an edge of the wafer, each of the two or more passes being made at the channeling angle relative to a plane of the wafer.

16. The method of claim 15 , wherein a number of the two or more passes is selected based on an order of symmetry of a crystallographic plane of the template material in a growth direction.

17. The method of claim 15 , wherein the two or more passes comprises three passes separated from each other by 120°.

18. The method of claim 13 , wherein Ne is used as a working gas for the ion beam milling and Ar is used as a neutralizing gas for the ion beam milling.

19. The method of claim 13 , wherein the template material is formed over an Au structure having an edge interfacing with AlO, and wherein the ion beam milling is performed at an angle β relative to an edge of the wafer, the angle β selected so that ions beams impact the AlO at the edge before impacting the Au structure.

20. The method of claim 13 , wherein the final structure comprises a component of a recording head.

21. The method of claim 13 , wherein the repetitions comprise two or more repetitions.

22. The method of claim 13 , wherein T1 and T2 satisfy at least one of:
values of at least one of T1 and T2 are different in at least two of the two or more repetitions; and
a ratio between T1 and T2 is different in at least two of the two or more repetitions.

Assignees

• Seagate Technology Llc

Inventors

• Zhao Tong
• Wan Li
• Kautzky Michael Christopher

Classifications

• H10P50/267

  using plasmas · CPC title

• H10P72/0421

  for drying etching · CPC title

• H10P50/244

  comprising alternated and repeated etching and passivation steps · CPC title

• H10P50/242

  of Group IV materials · CPC title

• B81C2201/0132

  Dry etching, i.e. plasma etching, barrel etching, reactive ion etching [RIE], sputter etching or ion milling · CPC title