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

• US 9,530,670 B2
• Filed: 09/22/2014
• Issued: 12/27/2016
• Est. Priority Date: 01/10/2014
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd., Soulbrain Co., Ltd.
• Original Assignee: 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
• Primary Examiner(s): Islam, Mohammad
• Assistant Examiner(s): Chang, Jay C
• Application Number:
  US14/492,122
• Publication Number:
  US 20150200112A1
• Time in Patent Office: 827 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: C09K 13/04 containing an inorganic acid
• CPC Class Codes: C23F 1/26 for etching refractory metals
• CPC Class Codes: H01L 21/32115 Planarisation
• CPC Class Codes: H01L 21/32133 by chemical means only
• CPC Class Codes: H01L 21/32134 by liquid etching only
• CPC Class Codes: H01L 29/4236 within a trench, e.g. trench gate electrode, groove gate electrode
• CPC Class Codes: H01L 29/4966 the conductor material next to the insulator being a composite material, e.g. organic material, TiN, MoSi2 H01L29/4908, H01L29/4983 take precedence
• CPC Class Codes: H01L 29/66666 Vertical transistors H01L29/66712, H01L29/66742 take precedence
• CPC Class Codes: H01L 29/7827 Vertical transistors H01L29/7802, H01L29/78642 take precedence
• CPC Class Codes: H10B 43/27 the channels comprising vertical portions, e.g. U-shaped channels

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.

Claims

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).