	US 12,308,214 B2
	Method of processing substrate
Bong-Soo Kwon, Yongin-si (KR); Se-Woong Bae, Yongin-si (KR); and Eun-Jin Song, Yongin-si (KR)
Assigned to TES CO., LTD, Yongin-si (KR)
Filed by TES Co., Ltd, Yongin-si (KR)
Filed on Nov. 14, 2022, as Appl. No. 17/986,147.
Claims priority of application No. 10-2021-0155334 (KR), filed on Nov. 12, 2021; and application No. 10-2022-0136823 (KR), filed on Oct. 21, 2022.
Prior Publication US 2023/0154731 A1, May 18, 2023
Int. Cl. H01L 21/67 (2006.01); H01J 37/32 (2006.01)

CPC H01J 37/32477 (2013.01) [H01J 37/32082 (2013.01); H01J 37/32357 (2013.01); H01J 37/32862 (2013.01); H01J 37/32788 (2013.01); H01J 2237/3346 (2013.01)]

15 Claims

1. A method of processing a substrate comprising an oxide-nitride-oxide stack in which a silicon oxide layer and a silicon nitride layer are stacked alternately and repeatedly on the substrate, comprising:

(a) primarily dry-etching silicon nitride layers of the oxide-nitride-oxide stack;

(b) producing oxygen radicals and processing silicon oxide layers of the oxide-nitride-oxide stack with the oxygen radicals after the primarily dry-etching the silicon nitride layers; and

wherein in steps (a) and (c), a plurality of gases are plasmatized to etch the silicon nitride layer, the plurality of gases including a first gas containing CF₄and a second gas containing hydrogen.

7. A method of processing a substrate comprising an oxide-nitride-oxide stack in which a silicon oxide layer and a silicon nitride layer are stacked alternately and repeatedly on the substrate, comprising:

(a) dry-etching silicon nitride layers of the oxide-nitride-oxide stack m times, wherein m is a natural number greater than or equal to 2; and

(b) dry-etching silicon nitride layers of the oxide-nitride-oxide stack n times, wherein n is a natural number greater than or equal to 2,

wherein step (a) includes one or more oxygen radical processing steps of processing silicon oxide layers of the oxide-nitride-oxide stack with oxygen radicals between primary dry etching and secondary dry etching of the m times,

wherein step (b) includes one or more oxygen radical processing steps of processing silicon oxide layers of the oxide-nitride-oxide stack with oxygen radicals between primary dry etching and secondary dry etching of the n times, and

wherein the dry etching of step (a) and the dry etching of step (b) include plasmatizing a plurality of gases and etching the silicon nitride layers, the plurality of gases including a first gas containing CF₄and a second gas containing hydrogen.