Process environment for inorganic resist patterning

Patent metadata

Field	Value
Publication number	US-11947262-B2
Application number	US-202117188679-A
Country	US
Kind code	B2
Filing date	Mar 1, 2021
Priority date	Mar 2, 2020
Publication date	Apr 2, 2024
Grant date	Apr 2, 2024

Abstract

The processing of radiation patternable organometallic coatings is shown to be improved through the appropriate selection of post processing conditions between coating and development of the pattern. In particular, a coated wafer can be subjected to process delays to allow aging of the coating at various process points, in particular following irradiation. Process delays can be combined and interspersed with heating steps. The atmosphere above the coated wafer at various process steps can be adjusted to obtain desired improvements in the development of the pattern. Reactive gases can be beneficial with respect to improvement of coating properties.

First claim

What is claimed is:

1. A method for forming a radiation patternable organo tin-based coating on a wafer, the coating having an average thickness from about 1 nm to about 500 nm, the method comprising:
contacting the wafer with the coating with an atmosphere comprising a CO 2 concentration from about 0.1 mole percent to about 10 mole percent prior to development to form a physical pattern having an increased critical dimension for a given exposure dose relative to a corresponding wafer not contacted with the atmosphere with CO 2 , the coating comprising a composition represented by the formula RSnO x OH 3-x wherein R is an organic ligand with 1-31 carbon atoms, with a carbon atom bonded to Sn and with one or more carbon atoms optionally substituted with one or more heteroatom functional groups, wherein the remaining atmosphere comprises an inert gas.

2. The method of claim 1 further comprising irradiating the coating with radiation having a pattern corresponding to the physical pattern prior to contacting the wafer with the coating.

3. The method of claim 2 further comprising heating the wafer at a temperature from about 45° C. to 250° C. after irradiating and prior to development.

4. The method of claim 3 wherein the heating is performed after contacting the wafer with the coating and is performed with an atmosphere comprising air, carbon dioxide, nitrogen, another reactive gas or a combination thereof.

5. The method of claim 3 wherein the heating is performed prior to contacting the wafer with the coating and is performed with an atmosphere comprising air, carbon dioxide, nitrogen, another reactive gas or a combination thereof.

6. The method of claim 1 wherein the atmosphere is at a temperature of about 45° C. to about 150° C.

7. The method of claim 6 wherein contacting the wafer with the coating has a duration of at least 20 minutes.

8. The method of claim 1 wherein contacting the wafer with the coating is under an atmosphere with a CO 2 concentration from about 0.25 mole percent to about 5 mole percent.

9. The method of claim 1 wherein the radiation patternable organo tin-based coating comprises a composition represented by the formula RSnO (1.5-(x/2)) (OH) x where 0<x≤3,
wherein R is an organic ligand with 1-31 carbon atoms, with a carbon atom bonded to Sn and with one or more carbon atoms optionally substituted with one or more heteroatom functional groups.

10. The method of claim 1 wherein contacting the wafer with the coating has a duration of at least about 40 minutes at a pressure of at least about 600 Torr.

11. The method of claim 1 wherein contacting the wafer with the coating has a duration of at least about 20 minutes at a pressure of at least about 200 Torr.

12. The method of claim 2 wherein contacting the wafer with the coating, after irradiating, has a duration of at least about 20 minutes at a pressure of at least about 200 Torr.

13. The method of claim 2 wherein contacting the wafer with the coating, after irradiating, has a duration of at least about 40 minutes at a pressure of at least about 600 Torr.

14. The method of claim 1 wherein inert gas comprises nitrogen and/or argon and the pressure is at least about 600 Torr.

15. The method of claim 1 wherein the inert gas comprises nitrogen.

16. The method of claim 1 wherein the atmosphere further comprises water vapor at a concentration of no more than 10 ppm.

17. The method of claim 1 wherein the CO 2 concentration during contacting the wafer with the coating varies by no more than about 20%.

18. The method of claim 11 further comprising heating the wafer at a temperature from about 95° C. to about 250° C. for 0.1 minute to 10 minutes prior to contacting the wafer with the coating and/or following contacting the wafer with the coating.

19. The method of claim 1 wherein the increase in critical dimension is at least about 0.25 nm.

20. The method of claim 1 wherein the exposure dose comprises EUV radiation.

Assignees

• Inpria Corp

Inventors

• Telecky Alan J
• Stowers Jason K
• Keszler Douglas A
• Meyers Stephen T
• De Schepper Peter
• Castellanos Ortega Sonia
• Greer Michael
• Louthan Kirsten

Classifications

• G03F7/38 Primary

  Treatment before imagewise removal, e.g. prebaking {(G03F7/265 takes precedence)} · CPC title

• G03F7/0042

  with inorganic or organometallic light-sensitive compounds not otherwise provided for, e.g. inorganic resists (G03F7/075 takes precedence) · CPC title

• G03F7/168

  Finishing the coated layer, e.g. drying, baking, soaking · CPC title