Integrated circuit structure having a capacitor structured to reduce dishing of metal layers

• US 8,878,337 B1
• Filed: 07/19/2011
• Issued: 11/04/2014
• Est. Priority Date: 07/19/2011
• Status: Active Grant

• Current Assignee: Xilinx, Inc. (Advanced Micro Devices, Inc.)
• Original Assignee: Xilinx, Inc. (Advanced Micro Devices, Inc.)
• Inventors: Pan, Hong-Tsz, Wu, Yun, Wu, Shuxian, Lin, Qi, Nguyen, Bang-Thu
• Primary Examiner(s): HENRY, CALEB E
• Application Number:
  US13/186,279
• Time in Patent Office: 1,204 Days
• Field of Search: 257/532, 257/E31.001, 361/271
• US Class Current: 257/532
• CPC Class Codes: H01L 21/3212 by chemical mechanical polishing [CMP]
• CPC Class Codes: H01L 21/823842 gate conductors with different gate conductor materials or different gate conductor implants, e.g. dual gate structures
• CPC Class Codes: H01L 27/0629 in combination with diodes, or resistors, or capacitors
• CPC Class Codes: H01L 29/66181 Conductor-insulator-semiconductor capacitors, e.g. trench capacitors
• CPC Class Codes: H01L 29/66545 using a dummy, i.e. replacement gate in a process wherein at least a part of the final gate is self aligned to the dummy gate
• CPC Class Codes: H01L 29/78 with field effect produced by an insulated gate H01L29/7725, H01L29/775, H01L29/778 take precedence
• CPC Class Codes: H01L 29/94 Metal-insulator-semiconductors, e.g. MOS

Abstract

A method and integrated circuit structure for mitigating metal gate dishing resulting from chemical mechanical polishing. The integrated circuit structure comprises a first area comprising at least one first type device; a second area comprising at least one second type device; a third area comprising at least one capacitor having an uppermost layer of polysilicon, where the capacitor area is greater than a sum of the first and second areas. The method utilizes the polysilicon of the capacitor to mitigate metal gate dishing of a metal gate of at least one device.

Claims

1. An integrated circuit structure, comprising:

a first area comprising at least one first type device that has a metal layer and a dielectric layer;

a second area comprising at least one second type device that has a metal layer and a dielectric layer;

wherein the metal layer of the first area has a first surface that defines a first plane, the metal layer of the second area has a second surface that defines a second plane, the dielectric layer of the first area has a third surface that defines a third plane, and the dielectric layer of the second area has a fourth surface that defines a fourth plane; and

a third area comprising at least one capacitor having an uppermost layer of polysilicon that has a surface that defines a fifth plane, and the capacitor having a dielectric layer that has a surface that defines a sixth plane,

wherein the first, second, and fifth planes are coplanar and the third, fourth, and sixth planes are coplanar,

wherein an area of the layer of polysilicon is greater than a sum of areas of the metal layers in the first and second areas, and

wherein the third area is distributed among the first and second areas.

2. The integrated circuit structure of claim 1, wherein the second type device is different from the first type device.

3. The integrated circuit structure of claim 2, wherein the first type device is an NMOS device and the second type device is a PMOS device.

4. The integrated circuit structure of claim 2, wherein the first type device is a PMOS device and the second type device is an NMOS device.

5. The integrated circuit structure of claim 1, wherein the at least one first type and at least one second type devices are fabricated using a gate last process.

6. The integrated circuit structure of claim 1, wherein the first area, second area and third area are arranged to have a surface in a checkerboard pattern.

7. The integrated circuit structure of claim 1, wherein the uppermost layer of polysilicon in the third area is located near a center of a substrate comprising the integrated circuit structure.

8. The integrated circuit structure of claim 1, wherein:

the first surface is opposite another surface of the metal layer of the first area that faces the dielectric layer of the first area; and

the second surface is opposite another surface of the metal layer of the second area that faces the dielectric layer of the second area.

9. A integrated circuit structure, comprising:

at least one first type device comprising a first metal electrode and a dielectric layer;

at least one second type device comprising a second metal electrode and a dielectric layer;

wherein the first metal electrode has a first surface that defines a first plane, the second metal electrode has a second surface that defines a second plane, the dielectric layer of the at least one first type device has a third surface that defines a third plane, and the dielectric layer of the at least one second type device has a fourth surface that defines a fourth plane; and

at least one capacitor comprising a polysilicon layer having a surface that defines a fifth plane, wherein the first, second, and fifth planes are coplanar to enable uniform polishing of the first and second metal electrodes, and the capacitor having a dielectric layer that has a surface that defines a sixth plane, wherein the third, fourth, and sixth planes are coplanar,

wherein the at least one capacitor is distributed among the first and second type devices.

10. The integrated circuit structure of claim 9, wherein the second type device is different from the first type device.

11. The integrated circuit structure of claim 10, wherein the first type device is an NMOS device or a PMOS device, respectively, and the second type device is a PMOS device or an NMOS device, respectively.

12. The integrated circuit structure of claim 9, wherein the at least one first type and at least one second type devices are fabricated using a gate last process.

13. The integrated circuit structure of claim 9, wherein the at least one first type device, the at least one second type device, and the at least one capacitor are arranged in a checkerboard pattern.

14. The integrated circuit structure of claim 9, wherein the polysilicon layer of the at least one capacitor is located near a center of a substrate comprising the integrated circuit structure.

15. The integrated circuit structure of claim 9, wherein:

the first surface is opposite another surface of the first metal electrode that faces the dielectric layer of the at least one first type device; and

the second surface is opposite another surface of the second metal electrode that faces the dielectric layer of the at least one second type device.