Resistor and manufacturing method thereof

• US 8,477,006 B2
• Filed: 08/30/2011
• Issued: 07/02/2013
• Est. Priority Date: 08/30/2011
• Status: Active Grant

• Current Assignee: United Microelectronics Corporation
• Original Assignee: United Microelectronics Corporation
• Inventors: Yang, Jie-Ning, Lin, Chun-Hsien, Wang, Yao-Chang, Hsu, Shih-Chieh, Pai, Chi-Horn, Tseng, Chi-Sheng
• Primary Examiner(s): LEE, KYUNG S
• Application Number:
  US13/220,721
• Publication Number:
  US 20130049924A1
• Time in Patent Office: 672 Days
• Field of Search: 338/314
• US Class Current: 338/314
• CPC Class Codes: H01L 27/0629 in combination with diodes, or resistors, or capacitors
• CPC Class Codes: H01L 28/20 Resistors
• 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

Abstract

A manufacturing method for a resistor integrated with a transistor having metal gate includes providing a substrate having a transistor region and a resistor region defined thereon, respectively forming a transistor having a dummy gate in the transistor region and a resistor in the resistor region, removing the dummy gate and portions of the resistor to form a first trench in the transistor and two second trenches in the resistor, forming at least a high-k gate dielectric layer in the first trench and the second trenches, and forming a metal gate in the first trench and metal structures respectively in the second trenches.

Claims

1. A manufacturing method for a resistor integrated with a transistor having metal gate, comprising:

providing a substrate having a transistor region and a resistor region defined thereon;

forming a transistor having a dummy gate in the transistor region and a resistor in the resistor region;

removing the dummy gate and portions of the resistor to form a first trench in the transistor and two second trenches in the resistor;

forming at least a high dielectric constant (high-k) gate dielectric layer in the first trench and the second trenches; and

forming a metal gate in the first trench and metal structures respectively in the second trenches.

2. The manufacturing method for a resistor integrated with a transistor having metal gate according to claim 1, wherein the dummy gate and the resistor comprise polysilicon.

3. The manufacturing method for a resistor integrated with a transistor having metal gate according to claim 1, wherein the second trenches are formed respectively at two opposite ends of the resistor.

4. The manufacturing method for a resistor integrated with a transistor having metal gate according to claim 1, further comprising:

forming a work function metal layer on the high-k gate dielectric layer in the first trench and the second trenches;

forming a blocking layer in the first trench and the second trenches; and

performing an etching process to remove the work function metal layer and the high-k gate dielectric layer not covered by the blocking layer.

5. The manufacturing method for a resistor integrated with a transistor having metal gate according to claim 4, wherein a height of the blocking layer is lower than a depth of the first trench and a depth of the second trenches.

6. The manufacturing method for a resistor integrated with a transistor having metal gate according to claim 4, wherein the high-k gate dielectric layer and the work function metal layer comprises a U shape.

7. The manufacturing method for a resistor integrated with a transistor having metal gate according to claim 6, wherein topmost portions of the high-k gate dielectric layer and the work function metal layer is lower than an opening of the second trenches.

8. The manufacturing method for a resistor integrated with a transistor having metal gate according to claim 4, further comprising forming a filling metal layer in the first trench and the second trenches after the etching process.

9. The manufacturing method for a resistor integrated with a transistor having metal gate according to claim 1, further comprising forming a first contact and two the second contacts on the substrate, the first contact is electrically connected to the metal gate and the second contacts are respectively electrically connected to the metal structures.

10. A resistor comprising:

a substrate;

a polysilicon portion positioned on the substrate; and

two metal portions respectively positioned on two opposite ends of the polysilicon portion, the metal portions respectively comprising a U-shaped high-k gate dielectric layer in bottoms.

11. The resistor according to claim 10, wherein a topmost portion of the U-shaped gate dielectric layer is lower than a surface of the metal portions.

12. The resistor according to claim 10, wherein the metal portions comprise a multilayered structure.

13. The resistor according to claim 12, wherein the metal portions further comprises a work function metal layer and a filling metal layer.

14. The resistor according to claim 13, wherein the work function metal layer comprises a U-shaped work function metal layer.

15. The resistor according to claim 14, wherein a topmost portion of the U-shaped work function metal layer is lower than a surface of the metal portions.