INTEGRATED CIRCUIT SHIELD STRUCTURE AND METHOD OF FABRICATION THEREOF

• US 20100120244A1
• Filed: 01/25/2010
• Published: 05/13/2010
• Est. Priority Date: 08/01/2007
• Status: Active Grant

• Current Assignee: Globalfoundries Singapore Pte Limited (GlobalFoundries, Inc.)
• Original Assignee: Chartered Semiconductor Manufacturing Incorporated (GlobalFoundries, Inc.)
• Inventors: CHEW, Kok Wai, CHU, Sanford Shao-Fu, CHENG, Michael Chye Huat, LIM, Suh Fei
• Granted Patent: US 8,003,529 B2
• Time in Patent Office: Days
• US Class Current: 438/657
• CPC Class Codes: H01L 23/5225 Shielding layers formed together 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 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 2001/0078 comprising spiral inductor on a substrate

Abstract

A method of forming an integrated circuit is disclosed. The method includes providing a substrate and forming on the substrate a shield structure comprising a shield member and a ground strap. The shield member comprises a non-metallic portion, and the ground strap comprises a metallic portion.

Claims

1. A method of forming an integrated circuit comprising:

providing a substrate; and

forming on the substrate a shield structure comprising a shield member and a ground strap,

wherein the shield member comprises a non-metallic portion, and the ground strap comprises a metallic portion.

2. The method as claimed in claim 1 wherein the shield member comprises at least one conductive region.

3. The method as claimed in claim 2 wherein the at least one conductive region is arranged substantially to inhibit an inducement of eddy current in the shield structure by a current in an inductor associated with the shield structure.

4. The method as claimed in claim 3 wherein the at least one conductive region comprises a comb pattern of a plurality of conductive line elements.

5. The method as claimed in claim 3 wherein the inductor has an inductor axis, the inductor axis being arranged to be substantially normal to a plane of the shield structure, the inductor axis passing through a centre of the inductor.

6. The method as claimed in claim 5 wherein the at least one conductive region is oriented at an angle of at least substantially 30°

to corresponding conductive track portions of the inductor, said corresponding conductive track portions being located directly above or below the at least one conductive region with respect to a direction parallel to the inductor axis.

7. The method as claimed in claim 5 wherein said at least one conductive region is arranged not to pass through said inductor axis.

8. The method as claimed in claim 1 wherein the shield member and ground strap are formed in the substrate.

9. The method as claimed in claim 1 wherein the substrate comprises a dielectric material.

10. A method of forming a semiconductor device comprising:

providing a substrate;

forming a shield member on the substrate, the shield member comprising a first material; and

forming a shield strap coupled to the shield member, the shield strap comprising a second material, wherein the second material comprises a metallic material and is different from the first material.

11. The method of claim 10, wherein the first material comprises a non-metallic material.

12. The method of claim 11, wherein the first material comprises undoped polysilicon, doped polysilicon or salicided doped polysilicon.

13. The method of claim 12 further comprising forming a first portion of the shield member comprising the first material and a second portion of the shield member comprising a third material wherein the third material comprises a diffusion region in the substrate.

14. The method of claim 13 wherein the second material comprises aluminum or copper.

15. The method of claim 11, wherein the first material is conductive.

16. The method of claim 11 wherein the shield member comprises polysilicon having a resistance in the range of megaohms.

17. The method of claim 10 comprising forming the shield member comprises forming first and second shield elements, wherein the first shield element comprises the first material and the second element comprises a third material, the third material being doped diffusion regions.

18. The method as claimed in claim 17 wherein the first and second shield elements are arranged in vertical overlap.

19. The method of claim 10 wherein the second material comprises aluminum or copper.

20. The method of claim 10 further comprising forming an inductor, wherein combination of the shield member and ground strap from the inductor axis beyond a periphery of an inductor.

21. The method of claim 20 wherein the inductor comprises an operational frequency and wherein at least a portion of the shield member has a thickness less than the skin depth of the portion of the shield member at the operational frequency.

22. The method of claim 10 wherein the shield strap is disposed around a periphery of the shield member.

23. A method of forming an integrated circuit structure comprising:

providing a substrate; and

a shield member and a ground strap formed on the substrate,

wherein the shield member comprises a plurality of conductive regions formed from a non-metallic material and arranged substantially to inhibit an inducement of eddy current in the shield member by a current in an inductor disposed adjacent to a shield portion, and the ground strap comprises a metallic portion.