Methods and apparatus for processing a substrate

Patent metadata

Field	Value
Publication number	US-11749532-B2
Application number	US-202117307383-A
Country	US
Kind code	B2
Filing date	May 4, 2021
Priority date	May 4, 2021
Publication date	Sep 5, 2023
Grant date	Sep 5, 2023

Abstract

Methods and apparatus for processing a substrate are provided. For example, a method of processing a substrate comprises supplying oxygen (O2) into a processing volume of an etch chamber to react with a silicon-based hardmask layer atop a base layer of ruthenium to form a covering of an SiO-like material over the silicon-based hardmask layer and etching the base layer of ruthenium using at least one of O2 or chloride (Cl2) while supplying nitrogen (N2) to sputter some of the SiO-like material onto an exposed ruthenium sidewall created during etching.

First claim

The invention claimed is:

1. A method of processing a substrate, comprising:
supplying oxygen (O 2 ) into a processing volume of an etch chamber to react with a silicon-based hardmask layer atop a base layer of ruthenium to form a covering of an SiO over the silicon-based hardmask layer;
etching the base layer of ruthenium using at least one of O 2 or chloride (Cl 2 ) while supplying nitrogen (N 2 ) to sputter some of the SiO onto an exposed ruthenium sidewall created during etching,
wherein etching the base layer of ruthenium further comprises providing:
a source power at a first power level at an operating frequency from about 50 KHz to about 150 MHz; and
a bias power at a second power level different from the first power level at an operating frequency from about 400 KHz to about 60 MHz; and
tuning a line profile of the exposed ruthenium sidewall by adjusting a flow rate of the nitrogen (N 2 ) supplied to sputter the SiO to about 200 sccm to control an amount of the base layer of ruthenium that is etched.

2. The method of claim 1 , further comprising etching the base layer of ruthenium to form multiple interconnect lines.

3. The method of claim 2 , wherein the multiple interconnect lines have a pitch of about 14 nm to about 28 nm.

4. The method of claim 2 , wherein the multiple interconnect lines have a pitch of about 24 nm.

5. The method of claim 1 , wherein the silicon-based hardmask layer comprises at least one of silicon (Si), silicon oxide (SiO), silicon nitride (SiN), or silicon carbide (SiC).

6. The method of claim 1 , wherein supplying oxygen (O 2 ) into the processing volume further comprises providing:
a source power of about 1500 W at an operating frequency from about 50 kHz to about 150 MHz;
a bias power of about 40 Wat an operating frequency from about 400 kHz to about 60 MHZ;
a chuck temperature of about 50° C.;
a pressure inside the etch chamber of about 10 mTorr; and
the oxygen (O 2 ) at about 200 sccm.

7. The method of claim 1 , wherein the first power level is about 500 W and the second power level is about 200 W and etching the base layer of ruthenium further comprises providing:
a chuck temperature of about 50° C.;
a pressure inside the etch chamber of about 10 mTorr;
the oxygen (O 2 ) at about 200 sccm when used; and
the chloride (Cl 2 ) at about 40 sccm when used.

8. A non-transitory computer readable storage medium having stored thereon instructions that when executed by a processor perform a method of a processing a substrate, the method comprising:
supplying oxygen (O 2 ) into a processing volume of an etch chamber to react with a silicon-based hardmask layer atop a base layer of ruthenium to form a covering of SiO over the silicon-based hardmask layer;
etching the base layer of ruthenium using at least one of O 2 or chloride (Cl 2 ) while supplying nitrogen (N 2 ) to sputter some of the SiO onto an exposed ruthenium sidewall created during etching,
wherein etching the base layer of ruthenium further comprises providing:
a source power at a first power level at an operating frequency from about 50 KHz to about 150 MHz; and
a bias power at a second power level different from the first power level at an operating frequency from about 400 kHz to about 60 MHz; and
tuning a line profile of the exposed ruthenium sidewall by adjusting a flow rate of the nitrogen (N 2 ) supplied to sputter the SiO to about 200 sccm to control an amount of the base layer of ruthenium that is etched.

9. The non-transitory computer readable storage medium of claim 8 , further comprising etching the base layer of ruthenium to form multiple interconnect lines.

10. The non-transitory computer readable storage medium of claim 9 , wherein the multiple interconnect lines have a pitch of about 14 nm to about 28 nm.

11. The non-transitory computer readable storage medium of claim 9 , wherein the multiple interconnect lines have a pitch of about 24 nm.

12. The non-transitory computer readable storage medium of claim 8 , wherein the silicon-based hardmask layer comprises at least one of silicon (Si), silicon oxide (SiO), silicon nitride (SiN), or silicon carbide (SiC).

13. The non-transitory computer readable storage medium of claim 8 , wherein supplying oxygen (O 2 ) into the processing volume further comprises providing:
a source power of about 1500 Wat an operating frequency from about 50 kHz to about 150 MHz;
a bias power of about 40 Wat an operating frequency from about 400 KHz to about 60 MHZ;
a chuck temperature of about 50° C.;
a pressure inside the etch chamber of about 10 mTorr; and
the oxygen (O 2 ) at about 200 sccm.

14. The non-transitory computer readable storage medium of claim 8 , wherein the first power level is about 500 W and the second power level is about 200 Wand etching the base layer of ruthenium further comprises providing:
a chuck temperature of about 50° C.;
a pressure inside the etch chamber of about 10 mTorr;
the oxygen (O 2 ) at about 200 sccm when used; and
the chloride (Cl 2 ) at about 40 sccm when used.

15. An etch chamber, comprising:
a gas panel configured to supply an etchant into a processing volume of the etch chamber;
a controller configured to:
supply oxygen (O 2 ) into the processing volume of the etch chamber to react with a silicon-based hardmask layer atop a base layer of ruthenium to form a covering of SiO over the silicon-based hardmask layer;
etch the base layer of ruthenium using at least one of O 2 or chloride (Cl 2 ) while supplying nitrogen (N 2 ) to sputter some of the SiO onto an exposed ruthenium sidewall created during etching,
wherein etching the base layer of ruthenium further comprises providing:
a source power at a first power level at an operating frequency from about 50 kHz to about 150 MHz; and
a bias power at a second power level different from the first power level at an operating frequency from about 400 KHz to about 60 MHz; and
tune a line profile of the exposed ruthenium sidewall by adjusting a flow rate of the nitrogen (N 2 ) supplied to sputter the SiO to about 200 sccm to control an amount of the base layer of ruthenium that is etched.

16. The etch chamber of claim 15 , wherein the controller is further configured to etch the base layer of ruthenium to form multiple interconnect lines.

17. The etch chamber of claim 16 , wherein the multiple interconnect lines have a pitch of about 14 nm to about 28 nm.

Assignees

• Applied Materials Inc

Inventors

• Jiang Hao
• Lu Chi
• Ren He
• Naik Mehul

Classifications

• H10W20/0633

  using subtractive patterning of the conductive members · CPC title

• H10P76/405

  characterised by their composition, e.g. multilayer masks · CPC title

• H10P72/0421

  for drying etching · CPC title

• H10P50/71 Primary

  using masks for conductive or resistive materials · CPC title

• H10W20/4432

  the principal metal being a noble metal, e.g. gold · CPC title