Composition and process for selectively etching metal nitrides

• US 9,831,088 B2
• Filed: 10/06/2011
• Issued: 11/28/2017
• Est. Priority Date: 10/06/2010
• Status: Active Grant

• Current Assignee: Entegris Incorporated
• Original Assignee: Entegris Incorporated
• Inventors: Chen, Tianniu, Thomas, Nicole E., Lippy, Steven, Barnes, Jeffrey A., Cooper, Emanuel I., Zhang, Peng
• Primary Examiner(s): Tran, Binh X
• Application Number:
  US13/877,777
• Publication Number:
  US 20140038420A1
• Time in Patent Office: 2,245 Days
• Field of Search: 438750, 438754, 216100, 216108, 216109
• CPC Class Codes: B81C 1/00539 Wet etching
• CPC Class Codes: H01L 21/28079 the final conductor layer next to the insulator being a single metal, e.g. Ta, W, Mo, Al
• CPC Class Codes: H01L 21/28088 the final conductor layer next to the insulator being a composite, e.g. TiN
• CPC Class Codes: H01L 21/32134 by liquid etching only
• CPC Class Codes: H01L 21/823842 gate conductors with different gate conductor materials or different gate conductor implants, e.g. dual gate structures

Abstract

A removal composition and process for selectively removing a first metal gate material (e.g., titanium nitride) relative to a second metal gate material (e.g., tantalum nitride) from a microelectronic device having said material thereon. The removal composition can include fluoride or alternatively be substantially devoid of fluoride. The substrate preferably comprises a high-k/metal gate integration scheme.

Claims

1. A method comprising:

contacting a substrate comprising a first metal gate material comprising titanium and a second metal gate material comprising tantalum with a removal composition, wherein the removal composition selectively removes the first metal gate material relative to the second metal gate material, wherein the removal composition comprises at least one oxidizing agent present in amount ranging from 0.01 wt. % to less than 10 wt. %, an etchant, and at least one metal nitride inhibitor, wherein the etchant comprises ammonium hydroxide or tetraalkylammonium salts of hydroxide and wherein the at least one metal nitride inhibitor comprises a species selected from the group consisting of boric acid, ammonium borates, ascorbic acid, L(+)-ascorbic acid, isoascorbic acid, ascorbic acid derivatives, gallic acid, 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP),-1-hydroxyethane-1,1-diphosphonic acid, nitrilotris(methylenephosphonic acid) (NTMPA), 1,5,9-triazacyclododecane-N,N′

,N″

-tris(methylenephosphonic acid) (DOTRP), 1,4,7,10-tetraazacyclododecane-N,N′

,N″

,N′

″

-tetrakis(methylenephosphonic acid) (DOTP), diethylenetriaminepenta(methylenephosphonic acid) (DETAP), aminotri(methylenephosphonic acid), bis(hexamethylene)triamine phosphonic acid, 1,4,7-triazacyclononane-N,N′

,N″

-tris(methylenephosphonic acid (NOTP), esters of phosphoric acids;

5-amino-1,3,4-thiadiazole-2-thiol (ATDT), benzotriazole (BTA), tannic acid, ethylenediaminetetraacetic acid (EDTA), uric acid, 1,2,4-triazole (TAZ), tolyltriazole, 5-phenyl-benzotriazole, 5-nitro-benzotriazole, 3-amino-5-mercapto-1,2,4-triazole, 1-amino-1,2,4-triazole, hydroxybenzotriazole, 2-(5-amino-pentyl)-benzotriazole, 1-amino-1,2,3-triazole, 1-amino-5-methyl-1,2,3-triazole, 3-amino-1,2,4-triazole, 3-mercapto-1,2,4-triazole, 3-isopropyl-1,2,4-triazole, 5-phenylthiol-benzotriazole, halo-benzotriazoles, naphthotriazole, 2-mercaptobenzimidazole (MBI), 2-mercaptobenzothiazole, 4-methyl-2-phenylimidazole, 2-mercaptothiazoline, 5-aminotetrazole, 2,4-diamino-6-methyl-1,3,5-triazine, thiazole, triazine, methyltetrazole, 1,3-dimethyl-2-imidazolidinone, 1,5-pentamethylenetetrazole, 1-phenyl-5-mercaptotetrazole, diaminomethyltriazine, imidazoline thione, mercaptobenzimidazole, 4-methyl-4H-1,2,4-triazole-3-thiol, benzothiazole, tritolyl phosphate, imidazole, indiazole, catechol, pyrogallol, resorcinol, hydroquinone, cyanuric acid, barbituric acid, 1,2-dimethylbarbituric acid, pyruvic acid, adenine, purine, glycine/ascorbic acid, p-tolylthiourea, phosphonobutane tricarboxylic acid (PBTCA), decylphosphonic acid, dodecylphosphonic acid (DDPA), tetradecylphosphonic acid, hexadecylphosphonic acid, bis(2-ethylhexyl)phosphate, octadecylphosphonic acid, perfluoroheptanoic acid, prefluorodecanoic acid, trifluoromethanesulfonic acid, phosphonoacetic acid, dodecylbenzenesulfonic acid, dodecenylsuccinic acid, dioctadecyl hydrogen phosphate, octadecyl dihydrogen phosphate, dodecylamine, dodecenylsuccinic acid monodiethanol amide, lauric acid, palmitic acid, oleic acid, juniperic acid, 12 hydroxystearic acid, octadecylphosphonic acid (ODPA), and combinations thereof.

2. The method of claim 1, wherein the removal composition does not substantially remove other gate stack materials present on the substrate.

3. The method of claim 1, wherein the first metal gate material comprises titanium nitride and the second metal gate material comprises tantalum nitride.

4. The method of claim 1, wherein the at least one oxidizing agent comprises a species selected from the group consisting of ozone, hydrogen peroxide, oxone, oxone tetrabutylammonium salt, ferric nitrate, potassium iodate, iodic acid, periodic acid, potassium permanganate, permanganic acid, chromium (III) oxide, ammonium cerium nitrate, nitric acid, ammonium chlorite, ammonium chlorate, ammonium iodate, ammonium perborate, ammonium perchlorate, ammonium periodate, ammonium persulfate, sodium persulfate, potassium persulfate, tetramethylammonium chlorite, tetramethylammonium chlorate, tetramethylammonium iodate, tetramethylammonium perborate, tetramethylammonium perchlorate, tetramethylammonium periodate, tetramethylammonium persulfate, urea hydrogen peroxide, peracetic acid, and combinations thereof.

5. The method of claim 1, wherein the at least one oxidizing agent comprises hydrogen peroxide.

6. The method of claim 1, wherein the removal composition further comprises at least one acid selected from the group consisting of sulfuric acid, nitric acid, acetic acid, trifluoroacetic acid, and hydrochloric acid.

7. The method of claim 1, wherein the at least one metal nitride inhibitor comprises 1-hydroxyethylidene-1,1-diphosphonic acid.

8. The method of claim 1, wherein the removal composition further comprises at least one surfactant.

9. The method of claim 1, wherein the removal composition is substantially devoid of fluoride.

10. The method of claim 1, wherein the removal composition is substantially devoid of abrasive or other inorganic particulate material, amines, chlorides, metal halides, silicates, and combinations thereof.

11. The method of claim 1, wherein the removal composition further comprises at least one solvent selected from the group consisting of water, methanol, ethanol, isopropanol, butanol, pentanol, hexanol, 2-ethyl-1-hexanol, heptanol, octanol, ethylene glycol, propylene glycol, butylene glycol, butylene carbonate, ethylene carbonate, propylene carbonate, dipropylene glycol, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, diethylene glycol monoethyl ether, triethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, triethylene glycol monobutyl ether, ethylene glycol monohexyl ether, diethylene glycol monohexyl ether, ethylene glycol phenyl ether, propylene glycol methyl ether, dipropylene glycol methyl ether (DPGME), tripropylene glycol methyl ether (TPGME), dipropylene glycol dimethyl ether, dipropylene glycol ethyl ether, propylene glycol n-propyl ether, dipropylene glycol n-propyl ether (DPGPE), tripropylene glycol n-propyl ether, propylene glycol n-butyl ether, dipropylene glycol n-butyl ether, tripropylene glycol n-butyl ether, propylene glycol phenyl ether, 2,3-dihydrodecafluoropentane, ethyl perfluorobutylether, methyl perfluorobutylether, alkyl carbonates, alkylene carbonates, 4-methyl-2-pentanol, dense fluid, and combinations thereof.

12. The method of claim 11, wherein the at least one solvent comprises water.