Integrated inductor

• US 6,791,158 B2
• Filed: 05/22/2003
• Issued: 09/14/2004
• Est. Priority Date: 08/04/2000
• Status: Expired due to Term

• Current Assignee: STMicroelectronics SA (STMicroelectronics NV)
• Original Assignee: STMicroelectronics SA (STMicroelectronics NV)
• Inventors: Lemaire, Frédéric
• Primary Examiner(s): Flynn, Nathan J.
• Assistant Examiner(s): Wilson, Scott R.
• Application Number:
  US10/343,897
• Publication Number:
  US 20030178694A1
• Time in Patent Office: 481 Days
• Field of Search: 257/499, 257/528, 257/531, 438/329
• US Class Current: 257/531
• CPC Class Codes: H01F 17/0006 Printed inductances printed coils for dynamo-electric machines H02K3/26; printed circuits H05K
• 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

Abstract

The invention concerns an intgrated inductor (20), consisting of a flat winding of one or several turns (21, 22, 23) made of a conductive material above a substrate provided with at least a subjacent conductive level wherein is produced, through a contact pick-up strip (12′), at least an intersection of the winding, the width of at least one turn and/or one interval between two turns being reduced in line with said contact pick-up strip.

Claims

1. An integrated inductance, formed above a semiconductor substrate supporting a conductive contact recovery track, comprising:

a flat winding having a turn and positioned above the substrate, in which the winding has a first winding portion that crosses above the contact recovery track, wherein the winding portion above said contact recovery track has a width that is reduced compared to a second winding portion that is not directly above the contact recovery track.

2. The inductance of claim 1, wherein the contact recovery track contacts and extends from an internal end of the winding to an external pad.

3. The inductance of claim 1, wherein the winding is conductive and has a resistance per square that is substantially smaller than a resistance per square of the contact recovery track, the winding having a thickness substantially greater than a thickness of the contact recovery track.

4. The inductance of claim 1, wherein the winding includes a third winding portion that crosses above the contact recovery track and is separated from the first winding portion by a first interval, and a fourth winding portion that is not directly above the contact recovery track and is separated from the second winding portion by a second interval that is greater than the first interval.

5. The inductance of claim 1, wherein the first winding portion has a length, which depends on the width of the contact recovery track, that is chosen to be as short as possible.

6. The inductance of claim 1, wherein the winding and the contact recovery track are made of aluminum.

7. The inductance of claim 1, wherein the winding is copper having a thickness of several tens of micrometers, the contact recovery track being made of aluminum of a thickness on the order of one micrometer.

8. The inductance of claim 1, wherein said contact recovery track is part of a conductive level formed by an upper metallization level used for interconnections of other components of an integrated circuit formed in the substrate.

9. The inductance of claim 1 wherein the winding includes a plurality of concentric spirals having respective first winding portions that respectively cross over the contact recovery track and remainders that do not cross the contact recovery track, each first winding portion having a reduced width compared to the remainder of the spiral.

10. An integrated inductance, formed above a semiconductor substrate that supports a conductive contact recovery track, comprising a winding of several turns, in which the winding includes first and second winding portions that each cross the contact recovery track and are separated from each other by a first interval, wherein at least one of the first and second winding portions is reduced compared to a third winding portion that does not cross the contact recovery track or the first interval is reduced compared to intervals between portions of the winding that do not cross the contact recovery track.

11. The inductance of claim 10, wherein the winding has an external turn with a turn portion adjacent to the contact recovery track that is closer to a center of the winding than is the rest of the external turn.

12. An inductance device, comprising:

a semiconductor substrate;

a conductive contact recovery track supported by the substrate and having first and second ends;

an insulating layer on the contact recovery track; and

a conductive winding, on the insulating layer, having an internal end and an external end, the internal end being electrically connected to the first end of the contact recovery track, the winding having a winding section with a first width that is directly above the contact recovery track and a second width that is not directly above the contact recovery track, the first width being smaller than the second width.

13. The inductance device of claim 12, wherein the contact recovery track extends from the internal end of the winding to an external pad that is external to the winding.

14. The inductance device of claim 12, wherein the winding has a resistance per square that is substantially smaller than a resistance per square of the contact recovery track, the winding having a thickness substantially greater than a thickness of the contact recovery track.

15. The inductance of claim 12, wherein the winding section includes first, second, third, and fourth winding portions, the first and second winding portions being above and crossing the contact recovery track and being separated from each other by a first interval;

the third and fourth winding portions being positioned not directly above the contact recovery track and being separated from each other by a second interval that is greater than the first interval.

16. The inductance of claim 12, wherein the winding section includes first, second, third, and fourth winding portions, the first and second winding portions being above and crossing the contact recovery track and being separated from each other by a first interval;

the third and fourth winding portions being positioned not directly above the contact recovery track and being separated from each other by a second interval, the first and second winding portions being narrower than the third and fourth winding portions.

17. The inductance device of claim 12, wherein the first width of the winding section is substantially constant across the contact recovery track and the winding section has an increased width beginning immediately adjacent to the portion of the winding section directly above the contact recovery track.

18. The inductance device of claim 12, wherein the first and second ends of the contact recovery track are separated by a distance that is less than the second width of the winding section.

19. The inductance device of claim 12, wherein the winding includes a plurality of concentric spirals, each of the spirals having a reduced width directly above the contact recovery track compared to the remainder of the spiral.

20. The inductance of claim 12 wherein the winding includes a plurality of concentric spirals having respective first winding portions that respectively cross over the contact recovery track and remainders that do not cross the contact recovery track, each first winding portion having a reduced width compared to the remainder of the spiral.