Chemical modification of hardmask films for enhanced etching and selective removal

Patent metadata

Field	Value
Publication number	US-9870915-B1
Application number	US-201615283400-A
Country	US
Kind code	B1
Filing date	Oct 1, 2016
Priority date	Oct 1, 2016
Publication date	Jan 16, 2018
Grant date	Jan 16, 2018

Abstract

Embodiments include a method of processing a hardmask that includes forming an alloyed carbon hardmask over an underlying layer. In an embodiment, the alloyed carbon hardmask is alloyed with metallic-carbon fillers. The embodiment further includes patterning the alloyed carbon hardmask and transferring the pattern of the alloyed carbon hardmask into the underlying layer. According to an embodiment, the method may further include removing the metallic component of the metallic-carbon fillers from the alloyed carbon hardmask to form a porous carbon hardmask. Thereafter, the porous hardmask may be removed. In an embodiment, the metallic component of the metallic-carbon fillers may include flowing a processing gas into a chamber that volatizes the metallic component of the metallic-carbon fillers.

First claim

What is claimed is:

1. A method of processing a hardmask, comprising:
forming an alloyed carbon hardmask over an underlying layer, wherein the alloyed carbon hardmask is alloyed with metallic-carbon fillers;
patterning the alloyed carbon hardmask;
transferring the pattern of the alloyed carbon hardmask into the underlying layer;
removing the metallic component of the metallic-carbon fillers from the alloyed carbon hardmask to form a porous carbon hardmask; and
removing the porous carbon hardmask.

2. The method of claim 1 , wherein removing the metallic component of the metallic-carbon fillers comprises:
flowing a processing gas into a chamber, wherein the processing gas volatizes the metallic component of the metallic-carbon fillers.

3. The method of claim 2 , wherein the processing gas is pulsed into the chamber.

4. The method of claim 3 , wherein the processing gas is pulsed into the chamber between 50 and 1000 times.

5. The method of claim 2 , wherein the processing chamber is operable at a pressure below approximately 25 torr.

6. The method of claim 2 , wherein a processing temperature is between approximately 400° C. and 650° C.

7. The method of claim 2 , wherein the metallic-carbon fillers are boron-carbides, tungsten-carbides, vanadium-carbides, niobium-carbides, tanalum-carbides, titanium-carbides, zirconium-carbides, hafnium-carbides, or aluminum carbides.

8. The method of claim 7 , wherein the processing gas is chlorine, bromine, iodine, hydrogen chloride, hydrogen bromide, hydrogen iodide, thionyl chloride, thionyl bromide, iodine monobromide, or sulfuryl chloride.

9. The method of claim 1 , wherein removing the metallic components of the metallic-carbon fillers and removing the porous carbon hardmask are performed as a single processing operation.

10. The method of claim 9 , wherein removing the metallic components of the metallic-carbon fillers and removing the porous carbon hardmask comprises:
alternating pulses of a first processing gas and a second processing gas into the chamber, wherein the first processing gas volatizes the metallic components of the metallic-carbon fillers, and wherein the second processing gas removes the porous carbon hardmask.

11. The method of claim 9 , wherein removing the metallic components of the metallic-carbon fillers and removing the porous carbon hardmask comprises:
simultaneously flowing a first processing gas and a second processing gas into a chamber, wherein the first processing gas volatizes the metallic components of the metallic-carbon fillers, and wherein the second processing gas removes the porous carbon hardmask.

12. A method of processing an alloyed carbon layer, comprising:
forming an alloyed carbon layer, wherein the carbon layer is alloyed with metallic-carbon fillers; and
removing the metallic component of the metallic-carbon fillers from the carbon layer to form a porous carbon layer.

13. The method of claim 12 , wherein removing the metallic components of the metallic-carbon fillers comprises:
flowing a processing gas into a chamber, wherein the processing gas volatizes the metallic portions of the metallic-carbon fillers.

14. The method of claim 13 , wherein the metallic-carbon fillers are boron-carbide fillers, and wherein the processing gas is chlorine, bromine, iodine, hydrogen chloride, hydrogen bromide, hydrogen iodide, thionyl chloride, thionyl bromide, iodine monobromide, or sulfuryl chloride.

15. The method of claim 13 , wherein removing the metallic portions of the metallic-carbon fillers is done in a processing chamber with in an inert atmosphere that is less than approximately 25 torr, and wherein a processing temperature is between approximately 400° C. and 650° C.

16. The method of claim 12 , wherein the alloyed carbon layer is formed in a first processing chamber and the metallic components of the metallic-carbon fillers are removed in the first processing chamber.

17. The method of claim 12 , further comprising:
alloying the porous carbon layer with a second filler.

18. A method of processing an alloyed carbon hardmask, comprising:
forming an alloyed carbon hardmask over an underlying layer, wherein the alloyed carbon hardmask is alloyed with boron-carbide fillers;
patterning the alloyed carbon hardmask;
transferring the pattern of the alloyed carbon hardmask into the underlying layer;
removing the boron component of the boron-carbide fillers from the alloyed carbon hardmask to form a porous carbon hardmask, wherein the boron component of the boron-carbide fillers are removed by introducing a first processing gas into a chamber, wherein the first processing gas volatizes the boron component of the boron-carbide fillers, and wherein the first processing gas is thionyl chloride gas or chlorine gas; and
removing the porous carbon hardmask, with a second processing gas.

19. The method of claim 18 , wherein removing the boron component of the boron-carbide fillers and removing the porous carbon hardmask comprises:
alternating pulses of the first processing gas and the second processing gas into the chamber.

20. The method of claim 18 , wherein removing the boron component of the boron-carbide fillers and removing the porous carbon hardmask comprises:
simultaneously flowing the first processing gas and the second processing gas into the chamber.

Assignees

• Knapp David
• Huang Simon
• Anthis Jeffrey W
• Kraus Philip Alan
• Thompson David
• Applied Materials Inc

Inventors

• Knapp David
• Huang Simon
• Anthis Jeffrey W
• Kraus Philip Alan
• Thompson David

Classifications

• H10P76/4085 Primary

  characterised by the processes involved to create the masks · CPC title

• H10P76/4083

  characterised by their behaviours during the lithography processes, e.g. soluble masks or redeposited masks · CPC title

• H10P70/23

  during, before or after processing of insulating materials · CPC title

• H10P76/405 Primary

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

• H10P50/73

  using masks for insulating materials · CPC title