	US 11,996,295 B2
	Pattern forming method and method for manufacturing semiconductor device
Hironobu Sato, Yokkaichi Mie (JP); and Yoshihiro Naka, Yokkaichi Mie (JP)
Assigned to KIOXIA CORPORATION, Tokyo (JP)
Filed by Kioxia Corporation, Tokyo (JP)
Filed on Sep. 1, 2021, as Appl. No. 17/463,774.
Claims priority of application No. 2020-156068 (JP), filed on Sep. 17, 2020.
Prior Publication US 2022/0084833 A1, Mar. 17, 2022
Int. Cl. H01L 21/308 (2006.01); H01L 21/02 (2006.01); H01L 21/027 (2006.01); H01L 21/033 (2006.01)

CPC H01L 21/3081 (2013.01) [H01L 21/0223 (2013.01); H01L 21/0274 (2013.01); H01L 21/0332 (2013.01)]

22 Claims

1. A pattern forming method comprising:

forming a first mask layer on a sample;

forming a second mask layer on the first mask layer, the second mask layer containing a first inorganic material and a first organic material;

performing a lithography in the second mask layer;

forming a pattern in the second mask layer;

oxidizing the first inorganic material and removing at least a portion of the first organic material from the second mask layer by exposing the second mask layer to a first oxidizing gas containing ozone; and

transferring the pattern to the first mask layer by etching the first mask layer with the second mask layer.

9. A pattern forming method comprising:

forming a first mask layer containing a first organic material on a sample;

forming a second mask layer containing a second organic material on the first mask layer;

processing the second mask layer to form a pattern;

forming a third mask layer on the second mask layer, the third mask layer containing a third inorganic material and a third organic material;

forming an inverted pattern to the pattern in the third mask layer;

oxidizing the third inorganic material and removing at least a portion of the third organic material from the third mask layer by exposing the third mask layer to a first oxidizing gas containing ozone; and

transferring the inverted pattern to the first mask layer by etching the first mask layer with the third mask layer.

15. A method for manufacturing a semiconductor device, the method comprising:

forming a first mask layer on a sample;

forming a second mask layer on the first mask layer, the second mask layer containing a first inorganic material and a first organic material;

performing a lithography in the second mask layer;

forming a pattern in the second mask layer;

transferring the pattern to the first mask layer by etching the first mask layer with the second mask layer to form an etching mask; and

etching the sample using the etching mask.