Inductor for radio frequency integrated circuit

• US 7,205,876 B2
• Filed: 09/12/2003
• Issued: 04/17/2007
• Est. Priority Date: 09/13/2002
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Kwang-du, Kim, Hoon-tae, Cho, Gea-ok
• Primary Examiner(s): Enad; Elvin
• Assistant Examiner(s): Rojas; Bernard
• Application Number:
  US10/660,801
• Publication Number:
  US 20040119574A1
• Time in Patent Office: 1,313 Days
• Field of Search: 336/200, 336/223, 336/225, 257/531, 257/701, 257750-752
• US Class Current: 336/200
• CPC Class Codes: H01F 17/0013 with stacked layers
• CPC Class Codes: H01F 17/0033 with the coil helically wound around a magnetic core
• CPC Class Codes: H01L 23/5227 Inductive arrangements or effects of, or between, wiring layers other inductive arrangements H01L23/645
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/3011 Impedance

Abstract

An inductor used in a radio frequency integrated circuit is disclosed. The inductor includes a plurality of unit inductors each having a vertical spiral structure, wherein a vertical cross-section of at least one unit inductor selected from the plurality of unit inductors is an inverted trapezoid.

Claims

1. An inductor, comprising:

a plurality of unit inductors, a vertical cross-section of at least one unit inductor of the plurality of unit inductors having a width that increases from a bottom surface of the at least one unit inductor to a top surface of the at least one unit inductor, the at least one unit inductor including a top metal layer extending across the width at the top surface; and

means for connecting a unit inductor to an adjacent unit inductor in the plurality of unit inductors in a direction perpendicular to the top metal layer, wherein the means includes metal layers extended from the unit inductors adjacent to the means and a conductive plug for connecting the extended metal layers.

2. The inductor as claimed in claim 1, wherein a vertical cross-section of all of the plurality of unit inductors has a width that increases from a bottom surface to a top surface of the unit inductor and a top metal layer extending across the width at the top surface.

3. The inductor as claimed in claim 2, wherein each unit inductor of the plurality of unit inductors has a same size.

4. The inductor as claimed in claim 3, each unit inductor of the plurality of unit inductors comprises:

a base metal layer at the bottom surface;

a multi-layer metal layer including two metal segments separated by a distance along the width, the multi-layer metal layer being between the base metal layer and the top metal layer; and

conductive plugs for vertically connecting adjacent metal layers.

5. The inductor as claimed in claim 2, wherein one unit inductor selected from the plurality of unit inductors has a size that is different from that of the rest.

6. The inductor as claimed in claim 5, wherein the at least one unit inductor selected from the plurality of unit inductors comprises:

multi-layer metal layers; and

conductive plugs that vertically connect the multi-layer metal layers, wherein layers of the multi-layer metal layers formed between top and bottom layers of the multi-layer metal layers include two metal layers, and metal layers of the multi-layer metal layers formed under the top layer of the multi-layer metal layers do not overlap except at portions thereof connected via the conductive plugs.

7. The inductor as claimed in claim 2, wherein each unit inductor of the plurality of unit inductors comprises:

a base metal layer at the bottom surface;

a multi-layer metal layer including two metal segments separated by a distance along the width, the multi-layer metal layer being between the base metal layer and the top metal layer; and

conductive plugs for vertically connecting adjacent metal layers.

8. The inductor as claimed in claim 7, wherein the top metal layer of the unit inductor is connected to the multi-layer metal layer of the adjacent unit inductor.

9. The inductor as claimed in claim 7, wherein each unit inductor further comprises at least two multi-layer metal layers between the base metal layer and the top metal layer, the metal segments of the at least two multi-layer metal layers only overlapping at portions thereof connected via the conductive plugs.

10. The inductor as claimed in claim 7, wherein one metal segment of the multi-layer metal layer extends along a length beyond the bottom metal layer.

11. The inductor as claimed in claim 1, wherein a vertical cross-section of remaining unit inductors has an inverted trapezoid, circular, triangular, rectangular, or elliptical structure.

12. The inductor as claimed in claim 11, each unit inductor of the plurality of unit inductors comprises:

a base metal layer at the bottom surface;

a multi-layer metal layer including two metal segements separated by a distance along the width, the multi-layer metal layer being between the base metal layer and the top metal layer; and

conductive plugs for vertically connecting adjacent metal layers.

13. The inductor as claimed in claim 1, wherein the at least one unit inductor comprises:

a base metal layer at the bottom surface;

a multi-layer metal layer including two metal segments separated by a distance along the width, the multi-layer metal layer being between the base metal layer and the top metal layer; and

conductive plugs for vertically connecting adjacent metal layers.

14. The inductor as claimed in claim 13, wherein at least one of a length, thickness, and width of metal layers formed on at least one layer of the multi-layer metal layers formed between the top layer of the multi-layer metal layers and the bottom layer of the multi-layer metal layers is different from a respective length, thickness, and width of the others.

15. The inductor as claimed in claim 13, wherein the conductive plugs have the same length.

16. The inductor as claimed in claim 13, wherein conductive plugs on different layers have different lengths.

17. The inductor as claimed in claim 13, wherein the at least one unit inductor further comprises at least two multi-layer metal layers between the base metal layer and the top metal layer, the metal segments of the at least two multi-layer metal layers only overlapping at portions thereof connected via the conductive plugs.

18. The inductor as claimed in claim 17, wherein the metal portions of the at least two multi-layer metal layers are symmetrical.

19. The inductor as claimed in claim 18, wherein the metal portions of the at least two multi-layer metal layers have a same length, thickness, and width.

20. The inductor as claimed in claim 18, wherein at least one of a length, thickness, and width of metal layers formed on different layers between the top layer of the multi-layer metal layers and the bottom layer of the multi-layer metal layers is different from a respective length, thickness, and width of the others.

21. The inductor as claimed in claim 17, wherein metal portions of the at least two multi-layer metal layers have a same length, thickness, and width.

22. The inductor as claimed in claim 13, wherein one metal segment of the multi-layer metal layer extends along a length beyond the bottom metal layer.

23. The inductor as claimed in claim 1, wherein the vertical cross-section of the at least one unit inductor of the plurality of unit inductors forms an inverted trapezoid.