Etching composition, a method of etching a metal barrier layer and a metal layer using the same, and method of manufacturing semiconductor device using the same

Patent metadata

Field	Value
Publication number	US-11028488-B2
Application number	US-201916574372-A
Country	US
Kind code	B2
Filing date	Sep 18, 2019
Priority date	Sep 18, 2018
Publication date	Jun 8, 2021
Grant date	Jun 8, 2021

Abstract

Disclosed is a method of etching a metal barrier layer and a metal layer. The method includes forming the metal barrier layer and the metal layer on a substrate, and using an etching composition to etch the metal barrier layer and the metal layer. The etching composition may include an oxidant selected from nitric acid, bromic acid, iodic acid, perchloric acid, perbromic acid, periodic acid, sulfuric acid, methane sulfonic acid, p-toluenesulfonic acid, benzenesulfonic acid, or a combination thereof, a metal etching inhibitor including a compound expressed by Chemical Formula 1, and a metal oxide solubilizer selected from phosphoric acid, phosphate, carboxylic acid having 3 to 20 carbon atoms, or a combination thereof.

First claim

What is claimed is:

1. A method of etching a metal barrier layer and a metal layer, the method comprising:
forming the metal barrier layer and the metal layer on a substrate; and
using an etching composition to etch the metal barrier layer and the metal layer,
wherein the etching composition includes:
an oxidant selected from the group consisting of nitric acid, bromic acid, iodic acid, perchloric acid, perbromic acid, periodic acid, sulfuric acid, methane sulfonic acid, p-toluenesulfonic acid, benzenesulfonic acid, and a combination thereof;
a metal etching inhibitor including a compound expressed by Formula (1) below; and
a metal oxide solubilizer selected from the group consisting of phosphoric acid, phosphate, carboxylic acid having 3 to 20 carbon atoms, and a combination thereof,

wherein, in Formula (1), R 1 and R 2 independently are hydrogen, C1-C10 alkyl, C3-C10 alkenyl, C3-C10 alkynyl, or C1-C10 alkoxy,
R 3 is hydrogen, amino, C1-C10 alkylamino, C3-C10 arylamino, C1-C10 alkyl, C3-C10 alkenyl, C3-C10 alkynyl, or C1-C10 alkoxy,
n is an integer equal to or greater than 1, and
R 1 , R 2 and R 3 are independently unsubstituted or substituted with hydroxy,
wherein the etching composition is selected to obtain an etch selectivity of from 1.0 to 2.0, where the etch selectivity is a ratio of an etch rate of the metal layer to an etch rate of the metal barrier layer,
the metal etching inhibitor is selected to reduce the etch rate of the metal layer to thereby reduce the etch selectivity as compared to a corresponding etching composition being the same as the etching composition except for not containing the metal etching inhibitor,
the metal layer includes at least one of tungsten, aluminum, copper, molybdenum, or cobalt, and
the metal barrier layer includes at least one of a titanium nitride (TiN) layer, a tantalum nitride (TaN) layer, a tungsten nitride (WN) layer, a nickel nitride (NiN) layer, a cobalt nitride (CoN) layer, or a platinum nitride (PtN) layer.

2. The method of claim 1 , wherein
an amount of the oxidant is from 10% to 30% by weight relative to a total weight of the etching composition, and
an amount of the metal etching inhibitor is from 0.01% to 10% by weight relative to the total weight of the etching composition.

3. The method of claim 1 , wherein
the etching composition further includes water,
an amount of the water is from 10% to 30% by weight relative to a total weight of the etching composition,
an amount of the oxidant is from 10% to 30% by weight relative to a total weight of the etching composition,
an amount of the metal etching inhibitor is from 0.01% to 10% by weight relative to the total weight of the etching composition, and
a remainder of the etching composition is the metal oxide solubilizer.

4. A method of etching a titanium nitride layer and a tungsten layer, the method comprising:
forming the titanium nitride layer and the tungsten layer on a substrate; and
using an etching composition to etch the titanium nitride layer and the tungsten layer,
wherein the etching composition includes:
an oxidant selected from the group consisting of nitric acid, bromic acid, iodic acid, perchloric acid, perbromic acid, periodic acid, sulfuric acid, methane sulfonic acid, p-toluenesulfonic acid, benzenesulfonic acid, and a combination thereof;
a metal etching inhibitor including an amine-based compound having one or two amino groups; and
a metal oxide solubilizer selected from the group consisting of phosphoric acid, phosphate, carboxylic acid having 3 to 20 carbon atoms, and a combination thereof,
wherein the etching composition is selected to obtain an etch selectivity of from 1.0 to 2.0, where the etch selectivity is a ratio of an etch rate of the tungsten layer to an etch rate of the titanium nitride layer, and
the metal etching inhibitor is selected to reduce the etch rate of the tungsten layer to thereby reduce the etch selectivity as compared to a corresponding etching composition being the same as the etching composition except for not containing the metal etching inhibitor.

5. The method of claim 4 , wherein an etch rate of the tungsten layer by the etching composition is greater than an etch rate of the titanium nitride layer by the etching composition.

6. The method of claim 4 , wherein
an amount of the oxidant is from 10% to 30% by weight relative to a total weight of the etching composition, and
an amount of the metal etching inhibitor is from 0.01% to 10% by weight relative to the total weight of the etching composition.

7. The method of claim 4 , wherein
the etching composition further includes water,
an amount of the water is from 10% to 30% by weight relative to a total weight of the etching composition,
an amount of the oxidant is from 10% to 30% by weight relative to a total weight of the etching composition,
an amount of the metal etching inhibitor is from 0.01% to 10% by weight relative to the total weight of the etching composition, and
a remainder of the etching composition is the metal oxide solubilizer.

8. The method of claim 4 , wherein the amine-based compound includes at least one of ethylenediaminediacetate, ethylenediamine m-xylylenediamine, methyldiethanolamine, dimethylmonoethanolamine, ethyldiethanolamine, diethylmonoethanolamine, triethylamine, or tributylamine.

9. A method of manufacturing a semiconductor device, the method comprising:
forming sacrificial layers and dielectric layers that are alternately and repeatedly stacked on a substrate;
selectively removing the sacrificial layers to form recess regions;
forming a metal barrier layer and a metal layer that fill the recess regions; and
using an etching composition to partially etch the metal barrier layer and the metal layer to form a metal barrier pattern and a metal pattern in each of the recess regions,
wherein the etching composition includes:
an oxidant selected from the group consisting of nitric acid, bromic acid, iodic acid, perchloric acid, perbromic acid, periodic acid, sulfuric acid, methane sulfonic acid, p-toluenesulfonic acid, benzenesulfonic acid, and a combination thereof;
a metal etching inhibitor including an amine-based compound having one or two amino groups; and
a metal oxide solubilizer selected from the group consisting of phosphoric acid, phosphate, carboxylic acid having 3 to 20 carbon atoms, and a combination thereof,
wherein the etching composition is selected to obtain an etch selectivity of from 1.0 to 2.0, where the etch selectivity is a ratio of an etch rate of the metal layer to an etch rate of the metal barrier layer,
the metal etching inhibitor is selected to reduce the etch rate of the metal layer to thereby reduce the etch selectivity as compared to a corresponding etching composition being the same as the etching composition except for not containing the metal etching inhibitor,
the metal layer includes at least one of tungsten, aluminum, copper, molybdenum, or cobalt, and
the metal barrier layer includes at least one of a titanium nitride (TiN) layer, a tantalum nitride (TaN) layer, a tungsten nitride (WN) layer, a nickel nitride (NiN) layer, a cobalt nitride (CoN) layer, or a platinum nitride (PtN) layer.

10. The method of claim 9 , wherein the metal barrier pattern and the metal pattern that are formed in each of the recess regions constitute an electrode, and
the electrodes are vertically spaced apart from each other across the dielectric layer.

11. The method of claim 9 , wherein
an amount of the oxidant is fro

Assignees

• Samsung Electronics Co Ltd
• Soulbrain Co Ltd

Inventors

• Kim Jungah
• Park Mihyun
• Lee Jinwoo
• KIM Keonyoung
• Lee Hyosan
• Han Hoon
• Lee Jin Uk
• Lim Jung Hun

Classifications

• H10P50/642 Primary

  Chemical etching · CPC title

• H10P50/283

  by chemical means · CPC title

• H10P50/667

  by liquid etching only · CPC title

• C09K13/04

  containing an inorganic acid · CPC title

• B81C1/00539

  Wet etching · CPC title