Multi-frequency inductors with low-k dielectric area

• US 9,966,182 B2
• Filed: 11/16/2015
• Issued: 05/08/2018
• Est. Priority Date: 11/16/2015
• Status: Active Grant

• Current Assignee: Globalfoundries US Incorporated (GlobalFoundries, Inc.)
• Original Assignee: GlobalFoundries, Inc.
• Inventors: Stamper, Anthony K., Vanukuru, Venkata Narayana Rao
• Primary Examiner(s): Enad, Elvin G
• Assistant Examiner(s): Barnes, Malcolm
• Application Number:
  US14/942,311
• Publication Number:
  US 20170140865A1
• Time in Patent Office: 904 Days
• CPC Class Codes: H01F 2027/2809 on stacked layers
• CPC Class Codes: H01F 21/12 discontinuously variable, e.g. tapped
• CPC Class Codes: H01F 27/2804 Printed windings
• CPC Class Codes: H01F 41/041 Printed circuit coils apparatus or processes for manufacturing printed circuits in general H05K3/00

Abstract

This disclosure relates generally to semiconductors, and more particularly, to structures and methods for implementing high performance multi-frequency inductors with airgaps or other low-k dielectric material. The structure includes: a plurality of concentric conductive bands; a low-k dielectric area selectively placed between inner windings of the plurality of concentric conductive bands; and insulator material with a higher-k dielectric material than the low-k dielectric area selectively placed between remaining windings of the plurality of concentric conductive bands.

Claims

1. A structure, comprising:

a plurality of concentric conductive bands;

a low-k dielectric area selectively placed between inner windings of the plurality of concentric conductive bands having interconnected wiring layers; and

insulator material with a higher-k dielectric material than the low-k dielectric area selectively placed between remaining windings of the plurality of concentric conductive bands having interconnected wiring layers in a different configuration than the inner windings.

2. The structure of claim 1, wherein the inner windings have fewer stacked wiring layers out of the interconnected wiring layers than the remaining windings of the plurality of concentric conductive bands.

3. The structure of claim 1, wherein the low-k dielectric area is at a center of the plurality of concentric conductive bands.

4. The structure of claim 3, wherein the low-k dielectric area is smaller compared to an overall inductor size.

5. The structure of claim 1, wherein the low-k dielectric area is an airgap.

6. The structure of claim 1, wherein the plurality of concentric conductive bands are symmetrical.

7. The structure of claim 6, wherein the plurality of concentric conductive bands have different wiring levels.

8. The structure of claim 7, wherein the low-k dielectric area extends to a bottom of a wiring level associated with the inner windings.

9. The structure of claim 8, wherein the inner windings are two innermost windings and the low-k dielectric area extends to a different wiring for each of two innermost windings.

10. The structure of claim 9, wherein the low-k dielectric area is a low-k or ultra low-k dielectric material.

11. The structure of claim 9, wherein

the low-k dielectric area is provided in a high frequency portion of the plurality of concentric conductive bands, and

a width of each concentric conductive band out of the plurality of concentric conductive bands decreases inwardly as the plurality of concentric conductive bands reach a center of the structure.

12. A multi-port inductor structure, comprising:

a plurality of conductive bands;

an airgap or low-k dielectric material placed between two innermost windings of the plurality of conductive bands having interconnected wiring layers in a parallel stacked band configuration; and

an insulator material with a dielectric constant greater than the airgap or low-k dielectric material is selectively placed between remaining windings of the plurality of conductive bands having interconnected wiring layers in a series band configuration.

13. The multi-port inductor structure of claim 12, wherein the plurality of conductive bands are symmetrical bands.

14. The multi-port inductor structure of claim 13, wherein the low-k dielectric material is ultra low-k dielectric material.

15. The multi-port inductor structure of claim 13, wherein the two innermost windings have fewer stacked wiring layers out of the interconnected wiring layers than remaining windings of the plurality of conductive bands.

16. The multi-port inductor structure of claim 15, wherein

the airgap or low-k dielectric material is provided at different wiring layers for the two innermost windings, and

an interspacing distance between each concentric conductive band out of the plurality of concentric conductive bands increases inwardly as the plurality of concentric conductive bands reach a center of the structure.

17. The multi-port inductor structure of claim 13, wherein the airgap or low-k dielectric material is provided in a high frequency portion of the plurality of conductive bands.

18. The multi-port inductor structure of claim 12, wherein the insulator material is silicon dioxide.

19. A method, comprising:

forming a plurality of conductive bands with two innermost windings having interconnected wiring layers in a first configuration and remaining windings having interconnected wiring layers in a second configuration;

forming low-k dielectric area between two innermost windings of the plurality of conductive bands; and

forming an insulator material with a dielectric constant greater than the low-k dielectric area between remaining windings of the plurality of conductive bands.