High quality factor inductive and capacitive circuit structure

• US 9,270,247 B2
• Filed: 11/27/2013
• Issued: 02/23/2016
• Est. Priority Date: 11/27/2013
• Status: Active Grant

• Current Assignee: Xilinx, Inc. (Advanced Micro Devices, Inc.)
• Original Assignee: Xilinx, Inc. (Advanced Micro Devices, Inc.)
• Inventors: Jing, Jing, Wu, Shuxian, Wu, Zhaoyin D.
• Primary Examiner(s): Lee, Benny
• Assistant Examiner(s): PATEL, RAKESH BHASKARBHAI
• Application Number:
  US14/092,241
• Publication Number:
  US 20150145615A1
• Time in Patent Office: 818 Days
• Field of Search: 333/133, 333174-175, 333/185, 333193-196, 336/200
• US Class Current: 1/1
• CPC Class Codes: H01L 23/5223 Capacitor integral with wiring layers
• CPC Class Codes: H01L 23/5227 Inductive arrangements or effects of, or between, wiring layers other inductive arrangements H01L23/645
• CPC Class Codes: H01L 27/016 Thin-film circuits
• CPC Class Codes: H01L 28/10 Inductors
• CPC Class Codes: H01L 28/60 Electrodes
• CPC Class Codes: H01L 28/88 made by patterning layers, e.g. by etching conductive layers
• 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: H03H 5/02 without voltage- or current-dependent elements
• CPC Class Codes: H03H 7/0115 comprising only inductors and capacitors H03H7/075, H03H7/09, H03H7/12, H03H7/13 take precedence
• CPC Class Codes: H03H 7/0138 Electrical filters or coupling circuits
• CPC Class Codes: H05K 1/16 incorporating printed electric components, e.g. printed resistor, capacitor, inductor
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing

Abstract

A circuit includes a first finger capacitor having a first bus line coupled to a first plurality of finger elements and a second bus line coupled to a second plurality of finger elements. The first bus line is parallel to the second bus line. The circuit further includes an inductor having a first leg oriented perpendicular to the first bus line and the second bus line. The first leg of the inductor is coupled to a center of the first bus line.

Claims

1. A circuit, comprising:

a first finger capacitor comprising a first bus line coupled to a first plurality of finger elements and a second bus line coupled to a second plurality of finger elements;

wherein the first bus line is parallel to the second bus line;

an inductor comprising a first leg oriented perpendicular to the first bus line and the second bus line;

wherein the first leg is implemented in a conductive layer above the first finger capacitor; and

a first via structure coupled between the first leg and the first bus line;

wherein the first leg of the inductor bisects the first finger capacitor and is coupled to a center of the first bus line by the first via structure; and

wherein the first via structure is disposed symmetrically about a line at the center of the first bus line that is perpendicular to the first bus line.

2. The circuit of claim 1, wherein:

the first plurality of finger elements and the second plurality of finger elements are perpendicular to the first and second bus lines; and

wherein individual ones of the first plurality of finger elements alternate with individual ones of the second plurality of finger elements.

3. The circuit of claim 2, wherein the first bus line, the second bus line, the first plurality of finger elements, and the second plurality of finger elements are implemented in a first plane.

4. The circuit of claim 3, wherein the inductor is implemented in at least a second plane different from the first plane and parallel to the first plane.

5. The circuit of claim 1, further comprising:

a second finger capacitor comprising a third bus line coupled to a third plurality of finger elements and a fourth bus line coupled to a fourth plurality of finger elements;

wherein the third bus line and the fourth bus line are parallel to the first bus line;

wherein the conductive layer is above the second finger capacitor; and

wherein the first leg of the inductor bisects the second finger capacitor and is coupled to a center of the third bus line by a second via structure.

6. The circuit of claim 1, further comprising:

a second finger capacitor comprising a third bus line coupled to a third plurality of finger elements and a fourth bus line coupled to a fourth plurality of finger elements;

wherein the third bus line and the fourth bus line are parallel to the first bus line;

wherein the inductor comprises a second leg parallel to the first leg;

wherein the second leg is implemented in the conductive layer and is above the second finger capacitor; and

wherein the second leg of the inductor bisects the second finger capacitor and is coupled to a center of the third bus line by a second via structure.

7. The circuit of claim 6, further comprising:

a first switch configured to selectively couple the second bus line to the fourth bus line.

8. The circuit of claim 6, further comprising:

a third finger capacitor comprising a fifth bus line coupled to a fifth plurality of finger elements and a sixth bus line coupled to a sixth plurality of finger elements;

wherein the fifth bus line and the sixth bus line are parallel to the first bus line;

wherein the conductive layer is above the third finger capacitor; and

wherein the first leg of the inductor bisects the third finger capacitor and is coupled to a center of the fifth bus line by a third via structure; and

a fourth finger capacitor comprising a seventh bus line coupled to a seventh plurality of finger elements and an eighth bus line coupled to an eighth plurality of finger elements;

wherein the seventh bus line and the eighth bus line are parallel to the first bus line;

wherein the conductive layer is above the fourth finger capacitor; and

wherein the second leg of the inductor bisects the fourth finger capacitor and is coupled to a center of the seventh bus line by a fourth via structure.

9. The circuit of claim 8, further comprising:

a second switch configured to selectively couple the sixth bus line to the eighth bus line.

10. A circuit, comprising:

a first plurality of finger capacitors implemented in a first plane;

wherein each finger capacitor of the first plurality of finger capacitors comprises a first bus line coupled to a first plurality of finger elements and a second bus line parallel to the first bus line and coupled to a second plurality of finger elements;

a second plurality of finger capacitors implemented in the first plane;

wherein each finger capacitor of the second plurality of finger capacitors comprises a third bus line coupled to a third plurality of finger elements and a fourth bus line parallel to the third bus line and coupled to a fourth plurality of finger elements;

wherein the third bus line is parallel to the first bus line;

an inductor comprising a first leg oriented perpendicular to the first bus line and a second leg parallel to the first leg;

wherein the first leg of the inductor is coupled to a center of each first bus line of the first plurality of finger capacitors;

wherein the second leg of the inductor is coupled to a center of each third bus line of the second plurality of finger capacitors;

wherein the first leg and the second leg are implemented within a conductive layer above the first and second plurality of finger capacitors; and

wherein the first leg bisects each of the finger capacitors of the first plurality of finger capacitors and the second leg bisects each of the finger capacitors of the second plurality of finger capacitors.

11. The circuit of claim 10, further comprising:

a plurality of switches, wherein each switch is individually configurable to couple each of the respective second bus lines to the corresponding fourth bus lines.

12. A method, comprising:

providing a first finger capacitor of a circuit;

wherein the first finger capacitor comprises a first bus line coupled to a first plurality of finger elements and a second bus line coupled to a second plurality of finger elements;

wherein the first bus line is parallel to the second bus line; and

providing an inductor comprising a first leg oriented perpendicular to the first bus line and the second bus line;

wherein the first leg is implemented in a conductive layer above the first finger capacitor; and

coupling a first via structure between the first leg and the first bus line;

wherein the first leg of the inductor bisects the first finger capacitor and is coupled to a center of the first bus line by the first via structure; and

wherein the first via structure is disposed symmetrically about a line at the center of the first bus line that is perpendicular to the first bus line.

13. The method of claim 12, wherein:

the first plurality of finger elements and the second plurality of finger elements are perpendicular to the first and second bus lines; and

wherein individual ones of the first plurality of finger elements alternate with individual ones of the second plurality of finger elements.

14. The method of claim 13, further comprising:

implementing the first bus line, the second bus line, the first plurality of finger elements, and the second plurality of finger elements in a first plane.

15. The method of claim 14, further comprising:

implementing the inductor in at least a second plane different from the first plane and parallel to the first plane.

16. The method of claim 12, further comprising:

providing a second finger capacitor comprising a third bus line coupled to a third plurality of finger elements and a fourth bus line coupled to a fourth plurality of finger elements;

wherein the third bus line and the fourth bus line are parallel to the first bus line; and

wherein the first leg of the inductor is coupled to a center of the third bus line.

17. The method of claim 12, further comprising:

providing a second finger capacitor comprising a third bus line coupled to a third plurality of finger elements and a fourth bus line coupled to a fourth plurality of finger elements;

wherein the third bus line and the fourth bus line are parallel to the first bus line;

wherein the inductor comprises a second leg parallel to the first leg;

wherein the second leg is implemented in the conductive layer and is above the second finger capacitor; and

wherein the second leg of the inductor bisects the second finger capacitor and is coupled to a center of the third bus line by a second via structure.

18. The method of claim 17, further comprising:

varying a capacitance of the circuit by selectively coupling the second bus line to the fourth bus line using a first switch.

19. The method of claim 17, further comprising:

providing a third finger capacitor comprising a fifth bus line coupled to a fifth plurality of finger elements and a sixth bus line coupled to a sixth plurality of finger elements;

wherein the fifth bus line and the sixth bus line are parallel to the first bus line;

wherein the conductive layer is above the third finger capacitor; and

wherein the first leg of the inductor bisects the third finger capacitor and is coupled to a center of the fifth bus line; and

providing a fourth finger capacitor comprising a seventh bus line coupled to a seventh plurality of finger elements and an eighth bus line coupled to an eighth plurality of finger elements;

wherein the seventh bus line and the eighth bus line are parallel to the first bus line;

wherein the conductive layer is above the fourth finger capacitor; and

wherein the second leg of the inductor bisects the fourth finger capacitor and is coupled to a center of the seventh bus line by a fourth via structure.

20. The method of claim 19, further comprising:

varying a capacitance of the circuit by selectively coupling the sixth bus line to the eighth bus line using a second switch.