Etching Solution for Tungsten Word Line Recess

Patent metadata

Field	Value
Publication number	US-2019284704-A1
Application number	US-201916297957-A
Country	US
Kind code	A1
Filing date	Mar 11, 2019
Priority date	Mar 16, 2018
Publication date	Sep 19, 2019
Grant date	—

Abstract

Described herein is an etching solution suitable for both tungsten-containing metals and TiN-containing materials, which comprises: water; and one or more than one oxidizers; and one or more than one of the components selected from the group consisting of: one or more fluorine-containing-etching compounds, one or more organic solvents, one or more chelating agents, one or more corrosion inhibitors and one or more surfactants.

First claim

1 . An etching solution suitable for both tungsten-containing metals and TiN-containing materials, which comprises:
water; one or more than one oxidizers; one or more of the components selected from: one or more fluorine-containing-etching compounds, one or more organic solvents, one or more chelating agents, one or more corrosion inhibitors, and one or more surfactants.

2 . The etching solution of claim 1 wherein said one or more oxidizers are selected from hydrogen peroxide (H2O2), FeCl3, FeF3, Sr(NO3)2, CoF3, MnF3, monopersulfate compound comprising KHSO5, KHSO4 and K2SO4, periodic acid, iodic acid, vanadium (V) oxide, vanadium (IV,V) oxide, ammonium vanadate, ammonium polyatomic salts, sodium polyatomic salts, potassium polyatomic salts, nitric acid (HNO3), potassium persulfate (K2S2O8), potassium hypochlorite (KClO)), tetramethylammonium polyatomic salts, tetrabutylammonium polyatomic salts, peroxomonosulfuric acid, ferric nitrate (Fe(NO3)3), urea hydrogen peroxide ((CO(NH2)2)H2O2), phosphoric acid (H3PO4), peracetic acid (CH3(CO)OOH), 1,4-benzoquinone, toluquinone, dimethyl-1,4-benzoquinone, chloranil, alloxan, N-methylmorpholine N-oxide, trimethylamine N-oxide, and mixtures thereof.

3 . The etching solution of claim 1 wherein said one or more oxidizers are selected from hydrogen peroxide (H2O2), phosphoric acid (H3PO4), nitric acid (HNO3), and mixtures thereof.

4 . The etching solution of claim 1 comprising said one or more fluorine-containing-etching compounds.

5 . The etching solution of claim 4 wherein said one or more fluorine-containing-etching compounds are selected from quaternary ammonium fluorides, HF, tetrafluoroboric acid, hexafluorosilicic acid, tetrabutylammonium tetrafluoroborate (TBA-BF4), H2ZrF6, H2TiF6, HPF6, ammonium hexafluorosilicate, ammonium hexafluorotitanate, and mixtures thereof.

6 . The etching solution of claim 4 wherein said one or more fluorine-containing-etching compounds are selected from quaternary ammonium fluorides and HF and mixtures thereof.

7 . The etching solution of claim 1 comprising said one or more organic solvents.

8 . The etching solution of claim 7 wherein said one or more organic solvents are selected from alcohols, glycol ethers, diols, glycerol, sulfoxides, amides, acids, esters, ketones, ethers, and mixtures thereof.

9 . The etching solution of claim 7 wherein said one or more organic solvents are selected from DMSO, pyridine, triethyl phosphate, DMAC, NMP, 1,3-Dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone, 1,3-dimethyl-2-imidazolidnone, 1-butyl-2-pyrrolidinone, methanesulfonic acid, propionic acid, lactic acid, acetic acid, 2-(1-Methoxy)propyl acetate, propylene carbonate, cyclopentanone, 1,4-dioxane, dimethoxyethane, poly(propylene glycol)monobutyl ether, sulfolane and mixtures thereof.

10 . The etching solution of claim 1 comprising said one or more corrosion inhibitors.

11 . The etching solution of claim 10 wherein said one or more corrosion inhibitors are selected from aromatic hydroxyl compounds, phenolic derivatives with at least the two hydroxyl groups, acetylenic alcohols, carboxyl group-containing organic compounds and anhydrides thereof, triazole compounds, D-fructose, L-ascorbic acid, vanillin, salicylic acid, diethyl hydroxylamine, amines, alkanolamines, heterocylic amines, polyethyleneimines, morpholines, piperazines, and mixtures thereof.

12 . The etching solution of claim 1 comprising one or more surfactants.

13 . The etching solution of claim 12 wherein said one or more surfactants are selected are selected from hexadecyl trimethylammonium p-toulenesulfonate, fluorosurfactants and mixtures thereof.

14 . The etching solution of claim 1 comprising one or more chelating agents.

15 . The etching solution of claim 14 wherein said one or more chelating agents are selected from (ethylenedinitrilo)tetraacetic acid (EDTA), butylenediaminetetraacetic acid, (1,2-cyclohexylenedinitrilo-)tetraacetic acid (CyDTA), diethylenetriaminepentaacetic acid (DETPA), ethylenediaminetetrapropionic acid, (hydroxyethyl)ethylenediaminetriacetic acid (HEDTA), N,N,N′,N′-ethylenediaminetetra(methylenephosphonic) acid (EDTMP), triethylenetetraminehexaacetic acid (TTHA), 1,3-diamino-2-hydroxypropane-N,N,N′,N′-tetraacetic acid (DHPTA), methyliminodiacetic acid, propylenediaminetetraacetic acid, nitrolotriacetic acid (NTA), citric acid, tannic acid, tartaric acid, gluconic acid, saccharic acid, glyceric acid, oxalic acid, phthalic acid, maleic acid, mandelic acid, malonic acid, salicylic acid, propyl gallate, pyrogallol, 8-hydroxyquinoline, and cysteine, and mixtures thereof.

16 . The etching solution of claim 1 wherein the solution is capable of etching TiN-containing material and tungsten-containing material at etch rates from about 1 to about 400 Å/min at room temperature.

17 . A method for etching both TiN-containing material and tungsten-containing metal from a microelectronic device comprising at least one of TiN-containing material and tungsten-containing material during the manufacture of the microelectronic device, the method comprising the steps of:
contacting the microelectronic device with an aqueous etching solution for a time sufficient to at least partially remove the TiN-containing material and the tungsten-containing metal from the device at rates of from about 1 to about 400 Å/min at room temperature, wherein the aqueous etching solution comprises water; one or more oxidizers; one or more of the components selected from: one or more fluorine-containing-etching compounds, one or more organic solvents, one or more chelating agents, one or more corrosion inhibitors, and one or more surfactants.

18 . The method of claim 17 wherein said aqueous etching solution comprises said one or more fluorine-containing-etching compounds.

19 . The method of claim 17 wherein said aqueous etching solution comprises said one or more corrosion inhibitors.

20 . The method of claim 17 wherein said aqueous etching solution comprises said one or more surfactants.

Assignees

• Versum Mat Us Llc

Inventors

• Ge Jhih Kuei
• Lee Yi-Chia
• Liu Wen Dar

Classifications

• H10P70/234

  the processing being the formation of vias or contact holes · CPC title

• H10P50/283

  by chemical means · CPC title

• H10P50/667 Primary

  by liquid etching only · CPC title

• C09K13/08

  containing a fluorine compound · CPC title

• C23F1/26 Primary

  for etching refractory metals · CPC title