Vacuum-integrated hardmask processes and apparatus

Patent metadata

Field	Value
Publication number	US-10831096-B2
Application number	US-201816206959-A
Country	US
Kind code	B2
Filing date	Nov 30, 2018
Priority date	Jan 31, 2014
Publication date	Nov 10, 2020
Grant date	Nov 10, 2020

Abstract

Vacuum-integrated photoresist-less methods and apparatuses for forming metal hardmasks can provide sub-30 nm patterning resolution. A metal-containing (e.g., metal salt or organometallic compound) film that is sensitive to a patterning agent is deposited on a semiconductor substrate. The metal-containing film is then patterned directly (i.e., without the use of a photoresist) by exposure to the patterning agent in a vacuum ambient to form the metal mask. For example, the metal-containing film is photosensitive and the patterning is conducted using sub-30 nm wavelength optical lithography, such as EUV lithography.

First claim

What is claimed is:

1. A photoresist-less method of forming a metal mask, comprising:
depositing by condensation on a semiconductor substrate an EUV-sensitive metal-containing solid film selected from the group consisting of Sn(CH 3 ) 4 with a thickness of between 5 and 200 Å, and crystalline HfCl 4 with a thickness of between 50 and 2000 nm;
patterning the metal-containing film with sub-30 nm resolution directly by EUV exposure having a wavelength in the range of 10 to 20 nm in a vacuum ambient; and
developing the pattern to form the metal mask.

2. The method of claim 1 , wherein the semiconductor substrate is a silicon wafer including partially-formed integrated circuits, and the method further comprising:
prior to the deposition, providing the semiconductor substrate in a first reactor chamber for the metal-containing film deposition; and
following the deposition, transferring the substrate under vacuum to a lithography processing chamber for the patterning.

3. The method of claim 2 , further comprising, prior to entering the lithography processing chamber, outgassing the substrate.

4. The method of claim 3 , wherein the outgassing comprises reducing the pressure surrounding the substrate to no more than 1E-8 Torr.

5. The method of claim 1 , further comprising pattern amplification by selective deposition on the metal mask.

6. The method of claim 5 , wherein the selective deposition comprises electroless deposition.

7. The method of claim 1 , wherein the EUV exposure has a wavelength of 13.5 nm.

8. The method of claim 1 , wherein the metal mask is formed on the substrate that is a silicon wafer including partially-formed integrated circuits.

9. The method of claim 1 , wherein the development of the pattern comprises heating the substrate to volatilize unexposed regions of the metal-containing film.

10. The method of claim 1 , wherein the solid film is the Sn(CH 3 ) 4 and is deposited at a temperature of about 20° C. at a reactor pressure of less than 20 Torr.

11. The method of claim 10 , wherein the solid film is deposited to the thickness of 100 Å with the reactor pressure maintained at about 1 Torr.

12. The method of claim 10 , wherein the patterning involves the following decomposition chemistry: Sn(CH 3 ) 4 →Sn+2C 2 H 6 .

13. The method of claim 1 , wherein the solid film is the crystalline HfCl 4 and is deposited at a temperature of between 0 and 300° C. at a reactor pressure of less than 10 Torr.

14. The method of claim 13 , wherein the solid film is deposited to the thickness of 1000 nm with the reactor pressure maintained between 0.1 and 1 Torr and the temperature at 100° C.

15. The method of claim 13 , wherein the patterning involves the following decomposition chemistry: HfCl 4 →Hf+2Cl 2 .

16. A photoresist-less method of forming a metal mask, comprising:
depositing by condensation on a semiconductor substrate an EUV-sensitive metal-containing solid film of SnBr 4 having a thickness of between 5 and 200 nm, wherein the solid film is deposited at a temperature between about 0 and 30° C. at a reactor pressure of less than 20 Torr;
patterning the metal-containing film with sub-30 nm resolution directly by EUV exposure having a wavelength in the range of 10 to 20 nm in a vacuum ambient; and
developing the pattern to form the metal mask.

17. The method of claim 16 , wherein the solid film is deposited to the thickness of 10 nm with the reactor pressure maintained between 14 and 15 Torr, and the temperature at 20° C.

18. The method of claim 16 , wherein the patterning involves the following decomposition chemistry: SnBr 4 →Sn+2Br 2 .

Assignees

• Lam Res Corp

Inventors

• Marks Jeffrey
• Antonelli George Andrew
• Gottscho Richard A
• Hausmann Dennis M
• Lavoie Adrien
• Knisley Thomas Joseph
• Reddy Sirish K
• Varadarajan Bhadri N
• Kolics Artur

Classifications

• H10P76/4085 Primary

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

• H10P76/405 Primary

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

• H10P72/0471

  comprising at least one ion or electron beam chamber · CPC title

• H10P72/0454

  surrounding a central transfer chamber · CPC title

• H10P72/0452

  characterised by the layout of the process chambers · CPC title