Tuning work function of p-metal work function films through vapor deposition

• US 11,018,009 B2
• Filed: 04/11/2019
• Issued: 05/25/2021
• Est. Priority Date: 04/19/2018
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Jian, Guoqiang, Tang, Wei, Lin, Chi-Chou, Ma, Paul, Yang, Yixiong, Chang, Mei, Liu, Wenyi
• Primary Examiner(s): Woldegeorgis, Ermias T
• Application Number:
  US16/381,776
• Publication Number:
  US 20190326120A1
• Time in Patent Office: 775 Days
• CPC Class Codes: C23C 16/34 Nitrides C23C16/303 takes precedence
• CPC Class Codes: C23C 16/45531 specially adapted for making ternary or higher compositions
• CPC Class Codes: H01L 2029/7858 having contacts specially adapted to the FinFET geometry, e.g. wrap-around contacts
• CPC Class Codes: H01L 21/02205 the layer being characterised by the precursor material for deposition
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/28088 the final conductor layer next to the insulator being a composite, e.g. TiN
• CPC Class Codes: H01L 21/28506 of conductive layers
• CPC Class Codes: H01L 21/324 Thermal treatment for modifying the properties of semiconductor bodies, e.g. annealing, sintering H01L21/20 - H01L21/288 and H01L21/302 - H01L21/322 take precedence
• CPC Class Codes: H01L 21/67017 Apparatus for fluid treatment H01L21/67126, H01L21/6715 take precedence
• CPC Class Codes: H01L 21/67248 Temperature monitoring
• CPC Class Codes: H01L 29/4966 the conductor material next to the insulator being a composite material, e.g. organic material, TiN, MoSi2 H01L29/4908, H01L29/4983 take precedence
• CPC Class Codes: H01L 29/66795 with a horizontal current flow in a vertical sidewall of a semiconductor body, e.g. FinFET, MuGFET
• CPC Class Codes: H01L 29/785 having a channel with a horizontal current flow in a vertical sidewall of a semiconductor body, e.g. FinFET, MuGFET

Abstract

The present disclosure relates to a method for forming a p-metal work function nitride film having a desired p-work function on a substrate, including: adjusting one or more of a temperature of a substrate, a duration of one or more temporally separated vapor phase pulses, a ratio of a tungsten precursor to a titanium precursor, or a pressure of a reaction to tune a work function of a p-metal work function nitride film to a desired p-work function, and contacting the substrate with temporally separated vapor phase pulses of the tungsten precursor, the titanium precursor, and a reactive gas to form a p-metal work function nitride film thereon having the desired p-work function.

Claims

1. A method for forming a p-metal work function nitride film having a desired p-work function on a substrate, comprising:

adjusting one or more of a temperature of a substrate, a duration of one or more temporally separated vapor phase pulses, a ratio of a tungsten precursor to a titanium precursor, or a pressure of a reaction to tune a work function of a p-metal work function nitride film to a desired p-work function, and

contacting the substrate with temporally separated vapor phase pulses of the tungsten precursor, the titanium precursor, and a reactive gas to form a p-metal work function nitride film thereon having the desired p-work function.

2. The method of claim 1, further comprising removing excess tungsten precursor, titanium precursor, and reactive gas after each vapor phase pulse.

3. The method of claim 2, wherein removing further comprises purging a reaction space with an inert gas.

4. The method of claim 1, wherein the temperature of the substrate is between about 250°

C. to about 500°

C.

5. The method of claim 1, wherein the temperature of the substrate is between about 375°

C. to about 400°

C.

6. The method of claim 1, wherein the temporally separated vapor phase pulses have a duration between about 0.1 seconds to 10 seconds.

7. The method of claim 1, wherein a duration of one or more temporally separated vapor phase pulses is between about 1 second to 5 seconds.

8. The method of claim 1, wherein the pressure of the reaction is between about 1 Torr to 50 Torr.

9. The method of claim 1, wherein the pressure of the reaction is between about 5 Torr to 25 Torr.

10. The method of claim 1, wherein the temperature of the substrate is between about 375°

C. to about 400°

C., wherein a duration of the temporally separated vapor phase pulses is between about 1 second to 5 seconds, wherein the pressure between about 5 Torr to 25 Torr.

11. The method of claim 1, wherein the p-metal work function nitride film further comprises carbide.

12. The method of claim 1, wherein the tungsten precursor comprises one or more of WCl₅, WCl₆, WF₆, bis(tert-butylimido)-bis(dimethylamido)tungsten-(VI).

13. The method of claim 1, wherein the titanium precursor comprises TiCl₄, TDMAT, TDEAT, or combinations thereof.

14. The method of claim 1, wherein the reactive gas comprises ammonia, hydrazine, or combinations thereof.

15. The method of claim 1, wherein the p-metal work function nitride film has a thickness of between about 10 angstroms to about 50 angstroms.

16. The method of claim 1, wherein the p-metal work function nitride film is deposited by an ALD process, a CVD process, or derivatives thereof.

17. A non-transitory computer readable medium having instructions stored thereon that, when executed, cause a method of forming a p-metal work function nitride film having a desired p-work function on a substrate in a process chamber, comprising:

adjusting one or more of a temperature of a substrate, a duration of one or more temporally separated vapor phase pulses, a ratio of a tungsten precursor to a titanium precursor, or a pressure of a reaction to tune a work function of a p-metal work function nitride film to a desired p-work function, and contacting the substrate with temporally separated vapor phase pulses of the tungsten precursor, the titanium precursor, and a reactive gas to form a p-metal work function nitride film thereon having the desired p-work function.