Monolithic integrated circuit incorporating an inductive component and process for fabricating such an integrated circuit

• US 6,459,135 B1
• Filed: 03/15/2000
• Issued: 10/01/2002
• Est. Priority Date: 03/23/1999
• Status: Expired due to Term

• Current Assignee: M-Red Inc. (Quest Patent Research Corporation)
• Original Assignee: Memscap Incorporated
• Inventors: Karam, Jean-Michel, Valentin, François, Basteres, Laurent, Mhani, Ahmed
• Primary Examiner(s): Loke, Steven
• Assistant Examiner(s): Tran, Thien F
• Application Number:
  US09/525,840
• Time in Patent Office: 930 Days
• Field of Search: 257/528, 257/531, 336/12, 336/65, 336/107, 336/138, 336/173, 336/186, 336/223, 336/225
• US Class Current: 257/528
• 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 28/10 Inductors
• 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

A monolithic integrated circuit (1) incorporating an inductive component (2) and comprising:

a semiconductor substrate layer (2);

a passivation layer (4) covering the substrate layer (2);

metal contact pads (5) connected to the substrate (2) and passing through the passivation layer (4) in order to be flush with the upper face (6) of the passivation layer (4);

which circuit also includes a spiral winding (20) which forms an inductor and lies in a plane parallel to the upper face (6) of the passivation layer (4), said winding (20) consisting of copper turns (21-23, 27, 28) having a thickness of greater than 10 microns, the winding ends forming extensions (12) which extend below the plane of the winding (20) and are connected to the contact pads (5).

Claims

1. A monolithic integrated circuit (1) incorporating an inductive component and comprising:

a semiconductor substrate layer (2);

a passivation layer (4) covering the substrate layer (2);

metal contact pads (5) connected to the substrate (2) and passing through the passivation layer (4) in order to be flush with the upper face (6) of the passivation layer (4);

which circuit also includes a spiral winding (20) which forms an inductor and lies in a plane parallel to the upper face (6) of the passivation layer (4), said winding (20) consisting of copper turns (21-23, 27, 28) having a thickness of greater than 10 microns, the winding ends forming extension (12) which extend below the plane of the winding (20) and are connected to the contact pads (5).

2. The monolithic integrated circuit as claimed in claim 1, wherein the plane in which the spiral winding lies is at a distance of greater than 10 microns from the upper face (6) of the passivation layer (4).

3. The monolithic integrated circuit as claimed in claim 1, which also includes a benzocyclobutene layer (9) on which the winding (20) forming the inductor rests.

4. The monolithic integrated circuit as claimed in claim 1, wherein the copper winding (20) is covered with a layer (28) of gold or gold-based alloy.

5. The monolithic integrated circuit as claimed in claim 1, wherein the space between two consecutive turns of the winding (20) is filled with air.

6. The monolithic integrated circuit as claimed in claim 1 wherein said circuit also includes an active region (3) between said substrate layer (2) and said passivation layer (4).

7. The monolithic integrated circuit as claimed in claim 1, which also includes a silica support layer (16) on which the winding (20) forming the inductor rests.

8. The monolithic integrated circuit as claimed in claim 7, wherein the support layer (16) is separated from the upper face of the passivation layer by a polyimide layer (9).

9. The monolithic integrated circuit as claimed in claim 7, wherein the support layer (16) is separated from the upper face (6) of the passivation layer (4) by a layer of air.