Methods of forming conductive patterns and methods of manufacturing semiconductor devices using the same using an etchant composition that includes phosphoric acid, nitric acid, and an assistant oxidant

Patent metadata

Field	Value
Publication number	US-9530670-B2
Application number	US-201414492122-A
Country	US
Kind code	B2
Filing date	Sep 22, 2014
Priority date	Jan 10, 2014
Publication date	Dec 27, 2016
Grant date	Dec 27, 2016

Abstract

The present disclosure herein relates to methods of forming conductive patterns and to methods of manufacturing semiconductor devices using the same. In some embodiments, a method of forming a conductive pattern includes forming a first conductive layer and a second conductive layer on a substrate. The first conductive layer and the second conductive layer may include a metal nitride and a metal, respectively. The first conductive layer and the second conductive layer may be etched using an etchant composition that includes phosphoric acid, nitric acid, an assistant oxidant and a remainder of water. The etchant composition may have substantially the same etching rate for the metal nitride and the metal.

First claim

What is claimed is:

1. A method of forming a conductive pattern, comprising:
forming a first conductive layer and a second conductive layer on a substrate, the first conductive layer including a metal nitride having a first metal and the second conductive layer including a second metal, wherein the first metal is different than the second metal, and wherein the metal nitride in the first conductive layer is titanium nitride and the second metal in the second conductive layer is tungsten;
etching the first conductive layer and the second conductive layer using an etchant composition that includes phosphoric acid, nitric acid, an assistant oxidant and water, the etchant composition having substantially the same etching rate for the metal nitride and the second metal; and
wherein hydrogen peroxide, acetic acid, a hydroxide and fluoric acid are not present in the etchant composition.

2. The method of claim 1 , wherein the etchant composition includes:
phosphoric acid in an amount in a range of about 50 weight percent to about 80 weight percent, based on a total weight of the etchant composition;
nitric acid in an amount in a range of about 5 weight percent to about 20 weight percent, based on the total weight of the etchant composition;
the assistant oxidant in an amount in a range of about 0.01 weight percent to about 10 weight percent, based on the total weight of the etchant composition; and
water in an amount of a remaining weight percent, based on the total weight of the etchant composition.

3. The method of claim 1 , wherein the assistant oxidant includes at least one selected from an acid ammonium-based compound, a halogen acid compound and a sulfuric acid-based compound.

4. The method of claim 3 , wherein the assistant oxidant includes at least one selected from ammonium sulfate, ammonium persulfate, ammonium acetate, ammonium phosphate, ammonium chloride, periodic acid, iodic acid, sulfuric acid, methanesulfonic acid and paratoluene sulfonic acid.

5. The method of claim 1 , wherein a conductive pattern including a first conductive layer pattern and a second conductive layer pattern is formed by etching the first conductive layer and the second conductive layer, and
wherein sidewalls of the first conductive layer pattern and the second conductive layer pattern extend on substantially the same plane.

6. The method of claim 1 , further comprising, prior to forming the first conductive layer and the second conductive layer on the substrate, forming an insulation layer pattern using silicon oxide on the substrate, the insulation layer pattern including an opening, and
wherein forming the first conductive layer and the second conductive layer on the substrate comprises forming the first conductive layer on surfaces of the insulation layer pattern and an innerwall of the opening, and forming the second conductive layer on the first conductive layer to fill the opening.

7. The method of claim 6 , wherein etching the first conductive layer and the second conductive layer comprises etching upper portions of the first conductive layer and the second conductive layer to form a first conductive layer pattern and a second conductive layer pattern, and
wherein the first conductive layer pattern surrounds a sidewall and a bottom of the second conductive layer pattern.

8. The method of claim 7 , wherein the first conductive layer pattern and the second conductive layer pattern partially fill the opening such that a recess is formed at an upper portion of the opening.

9. The method of claim 8 , wherein top surfaces of the first conductive layer pattern and the second conductive layer pattern are coplanar with each other.

10. A method of manufacturing a semiconductor device, comprising:
forming insulating interlayers and sacrificial layers alternately and repeatedly on a substrate;
forming a plurality of channels through the insulating interlayers and the sacrificial layers;
partially removing the insulating interlayers and the sacrificial layers to form an opening between adjacent channels of the plurality of channels;
removing the sacrificial layers exposed by the opening to form a plurality of gaps spaced apart from each other in a vertical direction to a top surface of the substrate;
forming a barrier conductive layer including a metal nitride having a first metal on surfaces of the insulating interlayers and innerwalls of the plurality of gaps;
forming a gate electrode layer including a second metal on the barrier conductive layer to fill the plurality of gaps;
etching the barrier conductive layer and the gate electrode layer using an etchant composition that includes phosphoric acid, nitric acid, an assistant oxidant and water, the etchant composition having substantially the same etching rate for the metal nitride and the second metal,
wherein the first metal is different than the second metal,
wherein the barrier conductive layer is formed using titanium nitride, and the gate electrode layer is formed using tungsten, and
wherein hydrogen peroxide, acetic acid, a hydroxide and fluoric acid are not present in the etchant composition.

11. The method of claim 10 , wherein a barrier conductive layer pattern and a gate electrode that at least partially fill a gap of the plurality of gaps are formed by etching the barrier conductive layer and the gate electrode layer, and
wherein sidewalls of the barrier conductive layer pattern and the gate electrode extend on substantially the same plane.

12. The method of claim 11 , further comprising forming a recess at a portion of a gap of the plurality of gaps, and
forming a filling layer pattern that fills the opening and the recess.

13. A method of forming a conductive pattern, comprising:
etching a first conductive layer including a first metal, wherein the first metal is tungsten, and a second conductive layer including a metal nitride, wherein the metal nitride is titanium nitride, having a second metal with an etchant composition comprising:
phosphoric acid in an amount in a range of about 65 weight percent to about 80 weight percent, based on a total weight of the etchant composition;
nitric acid in an amount in a range of about 5 weight percent to about 20 weight percent, based on the total weight of the etchant composition;
an assistant oxidant in an amount in a range of about 0.01 weight percent to about 10 weight percent, based on the total weight of the etchant composition,
wherein the etchant composition further comprises water,
wherein hydrogen peroxide, acetic acid, a hydroxide and fluoric acid are not present in the etchant composition,
wherein the etchant composition etches the metal nitride and the first metal at substantially the same etching rate, and
wherein the first metal is different than the second metal.

14. The method of claim 13 , wherein etching the first conductive layer and the second conductive layer comprises etching the metal nitride and first metal at an etching rate ratio in a range of about 0.8 to about 1.1 (metal nitride:first metal).

Assignees

• Samsung Electronics Co Ltd
• Soulbrain Co Ltd

Inventors

• Han Hoon
• Yoon Byoung-Moon
• Hong Young-Taek
• Kim Keon-Young
• Yang Jun-Youl
• Kim Young-Ok
• Kim Tae-Heon
• Song Sun-Joong
• Lim Jung-Hun
• Park Jae-Wan
• Lee Jin-Uk

Classifications

• H10P95/04

  Planarisation of conductive or resistive materials · CPC title

• H10P50/667

  by liquid etching only · CPC title

• H10P50/264 Primary

  by chemical means · CPC title

• H10D64/667

  the conductor comprising a layer of alloy material, compound material or organic material contacting the insulator, e.g. TiN workfunction layers (having lateral variation H10D64/671) · CPC title

• H10D64/513 Primary

  within recesses in the substrate, e.g. trench gates, groove gates or buried gates · CPC title