TWI791535B - Post etching residues cleaning solution with titanium nitride removal - Google Patents

Abstract

The present invention relates to a composition capable of achieving high TiN etching and removal of organic polymers and residues without damaging Cu, Co and/or Ru or risking the damage of other materials present in the structure, e.g. low-k materials, said composition comprising: a) an organic amine; b) one or more inhibitor(s); c) one or more buffer(s); d) an activator; e) one or more glycol ether(s); f) optionally an aprotic solvent; and g) water. The present invention also relates to a kit comprising said composition in combination with an oxidizer, and the use thereof.

Description

Post etch residue cleaning solution to remove titanium nitride

The present invention relates to compositions for post-implantation, etch/post-etch and post-ash related processes in the field of semiconductor/IC production. More specifically, the present invention relates to a composition having good cleaning performance against fluorocarbon (CFx) polymers and organic residues, capable of completely removing or shrinking metal hardmasks such as titanium nitride (TiN) , while protecting Cu, Co, and Ru as interconnect liners, caps, or barriers.

An integrated circuit (IC) consists of millions of active devices formed in or on a silicon substrate. Active devices that were initially isolated from each other are combined to form functional circuits and components. These devices are interconnected using well-known multilayer interconnects. Interconnect structures typically have a first metallization level, an interconnect level, a second metallization level, and more recently third and subsequent metallization levels.

In the field of semiconductor/IC production, post-etch residue (PER) is usually removed by a wet cleaning process. A solution comprising a complexing agent and water can be used here. Furthermore, selective etching of different layers within microelectronic structures is considered a critical and vital step in the IC fabrication process.

In the first and subsequent metallization layers, a high TiN etch rate is desired, and to achieve a high TiN etch rate, a high level of oxidizer is required to achieve a high level of TiN etch. Additionally, the dry etch step used in the multiple patterning process produces heavy fluorocarbon (CFx) polymers that are very difficult to remove from the surface of the IC structure. Therefore, it is also necessary to use an oxidizing agent to decompose the CFx polymer. In subsequent metallization layers comprising mainly copper (Cu-plugs), it is desirable to be able to etch the TiN at a rate at which the Cu-plugs are not significantly damaged. Depending on the respective thicknesses of the TiN and metal layers, which largely depends on the integration scheme used, a solution capable of tuning the etch rates of TiN and metal is required.

It should be understood that the presence of an oxidizing agent such as hydrogen peroxide in the formulation may be necessary to achieve a sufficiently high TiN etch rate. However, the increase in etch rate of copper and related metals (e.g. Co, Cu and Ru corrosion) by addition of oxidizing agents like hydrogen peroxide is an undesired effect. Therefore, a delicate balance must be struck between achieving a sufficiently high etch rate for TiN while removing CFx polymer on one side and achieving a sufficiently low etch rate for metals such as Cu, Co, and Ru on the other side . To achieve this, other components are added to the solution, for example, corrosion inhibitors, activators, buffer components and solvents.

Another problem is that when cleaning more and more wafers, along with the reaction of TiN with oxidizing agents such as hydrogen peroxide, the pH of the solution drops due to the formation of acidic reaction products (e.g., H2TiO3), which leads to a decrease in the TiN etch rate. decline. This problem is related to the recovery ability of the composition, which is very important and difficult to achieve in this field.

US 7,919,445 relates to a novel solution for removing post-etch residues. An imidazoline compound is preferably added as a corrosion inhibitor for treating the wafer surface.

WO03060045 relates to aqueous compositions for removing photoresist, etch and ash residues and contaminants from semiconductor substrates. A single corrosion inhibitor compound or a mixture of corrosion inhibitors such as benzotriazole, benzoic acid, malonic acid, gallic acid, catechol, ammonium malonate may be used in the stripping and cleaning composition. WO03060045 does not use an oxidizing agent to etch TiN, nor does it discuss protection of Cu, Co or Ru.

WO06138505 relates to dense fluid compositions, such as supercritical fluid compositions, for the removal of hardened photoresist, post etch residue and/or bottom antireflective coatings from the surface of microelectronic devices. However, the fluid composition contains at least one source of fluoride, which will damage the low-k dielectric material. WO06138505 is not concerned with etching of TiN and protection of Cu, Co or Ru.

Clearly, there is a need to find a composition that can achieve high TiN etch and remove CFx polymer without damaging Cu, Co or Ru, and without risking damage to other materials (eg, low-k materials) present in the structure. In addition, the frequently observed decrease in TiN etch rate with increased wafer loading due to reaction product buildup needs to be addressed to recycle the composition for continued use (recycling mode use). The object can be achieved by the composition of the present application.

Thus, the present invention provides a recyclable composition that enables high TiN etch and CFx polymer removal with substantially no etching of Cu, Co, and Ru, or no impact on other materials present in the structure (e.g., low-k materials) comprising: a) organic amines; b) one or more inhibitors; c) one or more buffers; d) activators; e) one or more glycol ethers; f ) an optional aprotic solvent; g) water.

Another aspect of the present invention is to use the above composition in combination with an oxidizing agent to adjust the etch rate of Cu/Co/Ru and TiN and/or remove organic and/or inorganic residues, the formulation comprising: A) a composition comprising: a ) organic amines; b) one or more inhibitors; c) one or more buffers; d) activators; e) one or more glycol ethers; f) optional aprotic solvents; g) water; B) Oxidizing agents, such as hydrogen peroxide, ozone water, persulfuric acid.

Other objects, advantages and novel features of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

While the present disclosure is susceptible to various forms of embodiments, the presently preferred embodiments will be described below, with the understanding that this disclosure should be considered an example of this disclosure and is not intended to limit the disclosure to the specific ones shown. Example.

In one embodiment of the present application, the composition is prepared by mixing: a) an organic amine; b) one or more inhibitors; c) one or more buffers; d) an activator; alcohol ether; f) optional aprotic solvent; g) water. The composition can be used to prepare formulations that can tune TiN and Cu/Co/Ru etch rates and remove polymers (residue) during semiconductor/IC manufacturing processes. For this purpose, an oxidizing agent can be added to the composition.

Thus, in another embodiment of the present application, the formulation is formulated by mixing in any order a) an organic amine, b) one or more inhibitors, c) one or more buffers, d) an activator, e) one or more B Glycol ethers, f) optional aprotic solvents and g) water, followed by addition of an oxidizing agent are prepared.

Then, the unpatterned wafer (TiN, Cu/Co/Ru, low-k) or the patterned wafer to be processed was broken into samples, which were then contacted with the prepared composition.

As shown in Figures 1 to 2, residue removal and TiN etching are carried out at the same time, and the etching rates of TiN and Cu/Co/Ru are controlled by changing the components in the composition. In addition, any remaining components on the surface can be removed by rinsing with an appropriate solvent or solvent mixture, such as water and/or isopropanol (IPA).

Organic amines combined with oxidizing agents can make polymers more water soluble. In addition, organic amines can stabilize the oxidant, making recycling and reuse of the composition possible. The organic amine may be selected from the following: 1-methylimidazole; imidazole; pyrazole; 4-acetylmorpholine; N-formylmorpholine; Hexahydrotriazine; 4-methylpyridine N-oxide; 2-methylpyridine N-oxide; 4-methoxypyridine N-oxide hydrate; 4-chloropyridine N-oxide; 8-methylpyridine Quinoline N-oxide; 1-dodecylamine, N,N-dimethyl-N-oxide; 4-methylmorpholine 4-oxide; 1-tetradecylamine, N,N- Dimethyl-N-oxide; (C ₁₀ -C ₁₆ )alkyldimethylamine oxide; (C _12-18 )alkyldimethyl-N-oxide; pyridine 1-oxide; decylamine , N,N-Dimethyl-N-oxide; Hexadecylamine, N,N-Dimethyl-N-oxide. Preferably, the organic amine may be selected from 4-methylmorpholine 4-oxide and 1,3,5-tris(dimethylaminopropyl)-sexahydrotriazine.

The amount of organic amine present in the composition of the invention may range from 0.01 to 25 wt%, preferably from 0.1 to 15 wt%, based on the total weight of the composition.

In a preferred embodiment, the amount of 4-methylmorpholine 4-oxide present in the composition as an organic amine ranges from 0.5 to 20 wt%, preferably 5 to 20 wt%, based on the total weight of the composition. 20 wt%, most preferably 8 to 15 wt%. For example, the amount of 4-methylmorpholine 4-oxide present in the composition as an organic amine is 8 wt % based on the total weight of the composition.

The inhibitor is a corrosion inhibitor of Cu, Co or Ru and may be selected from the classes of compounds known as polyethyleneimines (group a), azoles (group b) and their derivatives. The etch rate of various compounds can be controlled by changing the functional groups in various types of inhibitors.

(A) Polyethyleneimine: BASF Lupasol® FG, G20, G35, G100, PR8515, HF, P, PS, PO100, PN 50, PN 60, SK;

(B) Azoles: histidine, adenosine, adenine; pyridine; benzisodiazole; 2,2'-bipyridine;4,4'-bis(chloromethyl)-2,2'-bisPyridine;1,2,3-triazole;1,2,4-triazole;tetrazole; pentazole, 1,3,4-oxadiazole; oxadiazole, 1,2,3-oxadiazole; 1,2,5-oxadiazole; 1,2,4-oxadiazole; thiazole; 1,2,3-thiadiazole; 1,2,4-thiadiazole; 1,2,5-thiadiazole azole; 1,3,4-thiadiazole; benzotriazole (BTA); 5-alkylbenzotriazole (alkyl=-C _n H _2n+1 , where n=1-6); 6- Alkylbenzotriazole (alkyl=-C _n H _2n+1 , where n=1-6); 5-amino-benzotriazole; 6-amino-benzotriazole; 1-(methoxy Methyl)-1H-benzotriazole; 1H-benzotriazole-1-methanol; 1-(chloromethyl)-1H-benzotriazole; 5-phenyl-benzotriazole; N,N -Bis(2-ethylhexyl)-4-methyl-1H-benzotriazole-1-methanamine; N,N-bis(2-ethylhexyl)-5-methyl-1H-benzotriazole Azole-1-methylamine; 2,2'-[[(5-methyl-1H-benzotriazol-1-yl)methyl]imino]bisethanol;5-nitro-benzotriazole; Benzotriazole carboxylic acid; 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; 5-amino-1,2,4-triazole; 3 -Isopropyl-1,2,4-triazole; 3,5-Diamino-1,2,4-triazole; 5-phenylsulfidebenzotriazole; 5-halo-benzotriazole (halo = F, Cl, Br or I); 6-halo-benzotriazole (halo = F, Cl, Br or I); naphthotriazole; 4-methyl-2-phenylimidazole ;5-aminotetrazole; pentylenetetrazole; 5-phenyl-1H-tetrazole; 5-benzyl-1H-tetrazole; 5-methyltetrazole; -6-methyl-1,3,5-triazine; methyltetrazole; imidazolinone;

1,5-Pentene tetrazole, imidazoline thione; 4-Amino-4H-1,2,4-triazole; Benzothiazole; Benzimidazole.

The inhibitor may be present in the composition of the invention in an amount ranging from 0.01 to 6 wt%, preferably from 0.5 to 2 wt%, based on the total weight of the composition.

In a preferred embodiment, the amount of BTA and 6-methyl-benzotriazole present in the composition as inhibitors ranges from 0.1 to 6 wt % and 0.01 to 5 wt %, respectively, based on the total weight of the composition. wt%, preferably 0.5 to 3 wt% and 0.1 to 2 wt%, most preferably 0.8 to 2 wt% and 0.5 to 1 wt%. For example, the amounts of BTA and 6-methyl-benzotriazole present in the composition as inhibitors are 1 wt% and 1 wt%, respectively, based on the total weight of the composition.

(化學反應1)One of the possible reaction equations for oxidation and etching of TiN in the presence of hydrogen peroxide is given in Chemical Equation 1. The H ₂ TiO ₃ formed therein is acidic. Also, during this process, the ammonia formed in the reaction evaporates. Both processes contribute to a steady decrease in the pH of the solution, which causes changes in the etch rate of TiN and metal.

(chemical reaction 1)

(化學反應2)

(化學反應3)Additionally, according to chemical equations 2 and 3, hydrogen peroxide can be decomposed by reacting with Ti ⁴⁺ ions, releasing more protons and further reducing the pH of the composition:

(chemical reaction 2)

(chemical reaction 3)

In order to stabilize the etch rate of TiN, such effects of acid accumulation and ammonia evaporation must be compensated to ensure the pH stability of the composition. For this purpose, the concept of pH buffers can be applied to this mechanism and a buffer system added to the composition.

Buffer components may be selected from the following: ammonium hydroxide; phosphoric acid; tetramethylammonium hydroxide (TMAH); tetraethylammonium hydroxide (TEAH); tetrabutylammonium hydroxide; methanolamine (MEA); ethanolamine (DEA); Triethanolamine (TEA); Polyethylene glycol amine; Diethylene glycol amine; Triethylene glycol amine; 1,3,5-Tris(dimethylaminopropyl)-hexahydrotriazine.

Buffering agents may be present in the compositions of the invention in amounts ranging from 0.01 to 5 wt%, preferably 0.5 to 2 wt%, based on the total weight of the composition.

In a preferred embodiment, the amount of ammonium hydroxide and diammonium phosphate present in the composition as a buffering agent ranges from 0.01 to 1 wt% and 0.01 to 5 wt%, respectively, based on the total weight of the composition, Preferred are from 0.05 to 0.7 wt% and 0.1 to 2 wt%, most preferred are from 0.1 to 0.5 wt% and 0.5 to 1.5 wt%. For example, the amounts of ammonium hydroxide and diammonium phosphate present in the composition as buffers are 0.12 wt% and 1 wt%, respectively, based on the total weight of the composition.

Buffers can also be used to control pH to prevent corrosion of some sensitive metals such as Co at high pH. The inventors have found that the claimed composition, in the pH window of 6.0 to 7.5 when mixed with hydrogen peroxide, not only reduces Cu, Co and Ru corrosion, but also helps to make the dielectric material ( low-k film) damage is minimized.

However, lowering the pH also lowers the oxidation potential of hydrogen peroxide, leading to an undesired decrease in the etch rate of TiN. In this field, relatively high concentrations of oxidizing agents are generally required to achieve sufficiently high metal hardmask etch rates. Surprisingly, the inventors succeeded in discovering a series of activators to increase the etch rate of TiN at low pH. Therefore, when activators such as ammonium salts and quaternary ammonium salts are added to the composition to initiate the TiN/oxidant reaction, thereby reducing the amount of oxidant while maintaining a high TiN etch rate. Note that some activators may also be used as components of the buffer system described above.

The activator may be selected from the following: ammonium methanesulfonate; ammonium dihydrogen phosphate ((NH ₄ )H ₂ PO ₄ ); diammonium hydrogen phosphate (diammonium phosphate, (NH ₄ ) ₂ HPO ₄ ); ammonium phosphate (( NH ₄ ) ₃ PO ₄ ); Triammonium citrate; Ammonium acetate; Ammonium edetate; Tetraammonium edetate; Ammonium diethylenetriaminepentaacetate; Ammonium hydroxyethylethylenediaminetriacetate; Ammonium methylglycine diacetate; Triammonium nitrilotriacetate; Ammonium persulfate; Ammonium sulfate; Ammonium carbonate; Ammonium nitrate; Diboronic acid Ammonium; Ammonium carbamate; Ammonium fluoride; Ammonium hexafluorosilicate; Ammonium hexafluorotitanate; Ammonium metatungstate; Ammonium pentaborate; Ammonium tetrafluoroborate; Tetramethylammonium cyclohexylenedinitrotetraacetate; Tetramethylammonium ethylenediaminetetraacetate.

The amount of activator present in the composition of the invention may range from 0.01 to 3 wt%, preferably from 0.1 to 1 wt%, based on the total weight of the composition.

In a preferred embodiment, the amount of trans-1,2-cyclohexylidenedinitrotetraacetic acid present in the composition as an activator ranges from 0.01 to 0.5 wt%, based on the total weight of the composition , preferably from 0.05 to 0.3 wt%, most preferably from 0.08 to 0.2 wt%. For example, the amount of trans-1,2-cyclohexylidenenitrilotetraacetic acid present in the composition as an activator is 0.3 wt%, based on the total weight of the composition.

Partially water-miscible organic solvents can be used to lower surface tension and increase surface wetting without any of the disadvantages associated with typical surfactants (such as strong physical adsorption to the surface) and help dissolve organic Polymers and polymer residues (e.g. containing -CFx, -CHx). Glycol ethers are especially chosen as organic solvents and may be selected from the following: butyl glycol (BG), butyl diglycol (BDG), butyl triethylene glycol, n-hexyl diglycol, n-hexyl Alcohol, 2-hexyloxy-1-ethanol, tetrahydrofurfuryl alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, di Ethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monoisopropyl ether diethylene glycol monobutyl ether, diethylene glycol monoisobutyl ether, diethylene glycol Alcohol monobenzyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, triethylene glycol monomethyl ether, triethylene glycol dimethyl ether, polyethylene glycol monomethyl ether, diethylene glycol methyl ethyl ether , Triethylene glycol ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, propylene glycol dimethyl ether, propylene glycol monobutyl ether, propylene glycol, monopropyl ether, dipropylene glycol monomethyl ether , dipropylene glycol monopropyl ether, dipropylene glycol monoisopropyl ether, dipropylene glycol monobutyl ether, dipropylene glycol diisopropyl ether, tripropylene glycol monomethyl ether, 1-methoxy-2-butanol, 2-methoxy 1-butanol, 2-methoxy-2-methylbutanol, 1,1-dimethoxyethane and 2-(2-butoxyethoxy)ethanol.

The amount of glycol ether present in the composition of the invention may range from 1 to 60 wt%, preferably from 10 to 50 wt%, based on the total weight of the composition.

In a preferred embodiment, the amount of BDG present in the composition as a glycol ether ranges from 1 to 60 wt%, preferably from 10 to 55 wt%, based on the total weight of the composition, most preferably From 15 to 45 wt%. For example, the amount of BDG present in the composition as an activator is 30 wt%, based on the total weight of the composition.

Optionally, an aprotic solvent is also used in the composition to illustrate the dissolution of other components in the composition and to enhance the removal efficiency and solubility of organic residues from the wafer surface. Aprotic solvents, if present, may be selected from the following: dimethylsulfoxide (DMSO), cyclobutene, propylene carbonate, dimethylacetamide (DMAc), N-methyl-2-pyrrolidone ( NMP), dimethylformamide (DMF) or mixtures thereof.

Aprotic solvents, if present, may be present in the compositions of the invention in amounts from 1 to 50 wt%, preferably from 5 to 25 wt%, based on the total weight of the composition.

In a preferred embodiment, the amount of DMSO present in the composition as a solvent ranges from 1 to 50 wt%, preferably from 3 to 20 wt%, most preferably from 5 to 20 wt%, based on the total weight of the composition. 15 wt%. For example, the amount of BDG present in the composition as an activator is 30 wt%, based on the total weight of the composition.

The rest is water.

In another embodiment of the present invention, an oxidizing agent may be added to a compound containing a) an organic amine, b) one or more inhibitors, c) one or more buffers, d) an activator, e) one or more glycols ether, f) an optional aprotic solvent, and g) water to form a formulation. The oxidizing agent may be selected from hydrogen peroxide (H ₂ O ₂ ), ozone water, persulfuric acid.

The oxidizing agent may be added in a volume ratio (composition to oxidizing agent ratio comprising components a) to g) of: from 65:1 to 1:5 (approximately from 0.51 to 26.2 wt%), preferably from 33: 1 to 1:52 (approximately from 1 to 21.3 wt%), most preferably from 22:1 to 1:1 (approximately from 1.5 to 16.2 wt%).

In another embodiment of the present application, a kit is provided. The kit is composed of A) a composition and B) an oxidant, and the composition includes: a) an organic amine; b) one or more inhibitors; c) one or more buffers; d) an activator; or multiple glycol ethers; f) an optional aprotic solvent and g) water.

During semiconductor/IC production, the kit can be used to adjust the etch rate of Cu/Co/Ru and TiN respectively, and to remove organic polymers and residues from wafers.

The following experiments and examples were performed to illustrate the etch and etch rates of TiN and Cu/Co/Ru, respectively, and to show the removal of organic polymers and residues.

experiment:

A. Etching rate experiment:

Step 1. Unpatterned wafers (Cu/Co/Ru, TiN, low-k) or patterned wafers are selected from commercial sources.

Step 2. Break the wafer into smaller specimens 51 as shown in FIG. 3 .

Step 3. Measure the film thickness of the appropriate material:

1. For metals, use a 4-point probe or X-ray fluorescence (XRF) to measure layer thickness;

2. For non-metals, use ellipsometry to measure film thickness.

Step 4. Formulation 52 was prepared as described below.

Step 5. Place the formulation 52 in a thermocycler to achieve a stable target temperature; the temperature used is similar to that used in common industrial processes (approximately 40 to 70°C). The solution was stirred using a mechanical stirrer.

Step 6. The specimen is fixed in the mechanical holder.

Step 7. As shown in Figure 3, contact the sample with the solution for a period of time (typically 10 minutes).

Step 8. After a certain period of time, the contact between the solution and the sample is cut off, and the sample is cleaned with ultrapure water or IPA or a water/IPA mixture for about 2 to 5 minutes.

Step 9. Dry the specimen with _N2 gas and check to ensure that no water remains on the surface.

Step 10. Measure residue thickness as described in Step 3.

Step 11. Calculate the etch rate as described below.

For example, when the thickness before the reaction is 330 Å (A), the thickness after the reaction is 300 Å, and the reaction time is 10 minutes, the etching rate is calculated as follows: Etching rate = (330-300/10 = 3Å/min

B. Patterned Wafer Surface Residue Composition Evaluation

The steps are the same as A, but steps 3, 10 and 11 are not performed.

Example:

The following examples are given to allow a better understanding of the present disclosure. These examples should not be construed as narrowing the scope of the present disclosure in any way.

All percentage data in this specification are percentages by weight based on the total weight of the composition, except that the oxidizing agent is added in a volume ratio of the composition comprising components a) to g) to the oxidizing agent. It goes without saying that the amounts of components a) to g) added to the composition add up to 100%.

Various examples were carried out following the steps described above as outlined below to illustrate the present disclosure and a comparison between the prior art and the present disclosure.

Instances 1 to 6

The role of organic amines

In examples 1 to 6, tetraammonium edetate was used as activator, BDG was used as glycol ether, DMSO was used as aprotic solvent, and BTA was used as inhibitor, while in examples 1-2, 3-4 In and 5-6, imidazole, 1-methylmorpholine-4-oxide or 1,3,5-tris(dimethylaminopropyl)-shexahydrotriazine were used as the organic amine, respectively. The rest is water. Table 1

The results in Table 1 show that the TiN E/R increases with the amount of organic amines, and the smallest Co and Cu E/R (Å/min) can be obtained with suitable organic amines.

Example 7-17

The role of activators

In example 7-17, 4-methylmorpholine 4-oxide is used as organic amine, BDG is used as glycol ether, DMSO is used as aprotic solvent, and BTA is used as inhibitor, and in example 7-9, In 10-11, 12-13, 14-15 and 16-17, tetraammonium ethylenediamine tetraacetate, trans-1,2-cyclohexylidene dinitrotetraammonium tetraacetate and triammonium citrate were used respectively , ammonium acetate or diammonium hydrogen phosphate as an activator. The rest is water. Table 2

The results in Table 2 show that the TiN E/R is very low when no activator is used (Example 7), and the TiN E/R increases significantly with increasing activator dose.

Examples 18-24

The role of inhibitors

In Examples 18-24, 4-methylmorpholine 4-oxide was used as the organic amine, trans-1,2-cyclohexylidenedinitrotetraammonium tetraacetate was used as the activator, and BDG was used as the Alcohol ethers, using DMSO as an aprotic solvent, while BTA, N,N-bis(2-ethylhexyl)-4-methyl-1H-benzotriazole-1-methylamine, N,N-bis( 2-Ethylhexyl)-5-methyl-1H-benzotriazole-1-methanamine, 2,2'-[[(5-methyl-1H-benzotriazol-1-yl)methyl One or more of ]imino]bisethanol and 6-methyl-benzotriazole are used as inhibitors, respectively. The rest is water. table 3

The results in Table 3 show that Cu/Co E/R decreases significantly with different inhibitor combinations while maintaining similar TiN E/R. Ru E/R was not detected. That is, the protection of Cu/Co/Ru can be achieved without compromising the TiN E/R if an appropriate combination of inhibitors is used.

Examples 25-28

The role of buffer

In Examples 25-28, 4-methylmorpholine 4-oxide was used as the organic amine, tetraammonium trans-1,2-cyclohexylidenedinitrotetraacetate was used as the activator, and BDG was used as the diol Ether, using DMSO as the aprotic solvent, using BTA, 2,2'-[[(5-methyl-1H-benzotriazol-1-yl)methyl]imino]bisethanol and 5-methyl - Benzotriazole as inhibitor, and one or more of TMAH (tetramethylammonium hydroxide), TEAH (tetraethylammonium hydroxide), ammonium hydroxide, diglycolamine and triethyleneglycolamine buffer. The rest is water. Table 4

The results in Table 4 show that the pH drops significantly when no buffer is used (Example 25), which also leads to a drop in TiN E/R. Furthermore, Cu/Co/Ru and good TiN E/R protection can be achieved if an appropriate combination of buffers is used.

Examples 29-34

Composition: Effect of H ₂ O ₂ Volume Ratio

In Examples 29-34, 4-methylmorpholine 4-oxide was used as the organic amine, trans-1,2-cyclohexylidenedinitrotetraammonium tetraacetate was used as the activator, and BDG was used as the Alcohol ethers, using DMSO as the aprotic solvent, BTA as the inhibitor, and no buffer. The rest is water. table 5

The results in Table 5 show that TiN E/R _increases with the _amount of _H2O2 added in the volume ratio, and _the best TiN E/R and Cu/Co/Ru protection.

Examples 35-43

The role of solvents

In Examples 35-43, 4-methylmorpholine 4-oxide was used as the organic amine, tetraammonium trans-1,2-cyclohexylidenedinitrotetraacetate was used as the activator, and DMSO was used as the aprotic solvent, using BTA, 2,2'-[[(5-methyl-1H-benzotriazol-1-yl)methyl]imino]bisethanol and 5-methyl-benzotriazole as inhibitors agent, using TMAH (tetramethylammonium hydroxide), TEAH (tetraethylammonium hydroxide) and ammonium hydroxide as buffers, while butyl glycol, butyl triethylene glycol, BDG, n-hexyl diglycol , n-hexyl glycol and dipropylene glycol monomethyl ether were used as glycol ethers, respectively. The rest is water. Table 6

The results in Table 6 show that the combination of different solvents (especially glycol ethers) will lead to different TiN and Co/Cu E/R.

Therefore, good protection of TiN E/R and Cu/Co/Ru can be achieved if an appropriate solvent combination is used.

As can be seen from the results in the table above, the compositions used allow control of the etch rate ratio of TiN and Co and/or Cu and/or Ru.

In this disclosure, the words "a" or "an" should be understood to include both the singular and the plural. Conversely, any reference to plural items shall include the singular where appropriate.

From the foregoing it will be apparent that many modifications and variations can be made without departing from the true spirit and scope of the novel concepts of the present disclosure. It should be understood that no limitation is intended or should be inferred with respect to the particular embodiment or example shown. This disclosure is intended to cover by the appended claims all such modifications which fall within the scope of the claims.

11‧‧‧residue containing C, O, F, Ti and N 12‧‧‧Cu layer 13‧‧‧Co or Ru barrier layer 14‧‧‧low-k material 15‧‧‧TiN51‧‧‧sample 52‧ ‧‧preparation

Figure 1 shows a generic structure on a wafer in the first metallization layer, specifying a residue containing C, O, F, Ti, and N 11, a Cu layer 12, a Co or Ru barrier layer 13, a low-k material 14, and TiN 15. FIG. 2 shows the removal of a residue 11 containing C, O, F, Ti and N and the partial etching and complete removal of TiN 15 in the first metallization layer. Figure 3 schematically depicts the experimental setup used in the experiments (thickness measurement; etch rate; cleaning performance (SEM, TEM, XPS...)).

11‧‧‧Residues containing C, O, F, Ti and N

12‧‧‧Cu layer

13‧‧‧Co or Ru barrier layer

14‧‧‧Low-k materials

15‧‧‧TiN

Claims (15)

A composition consisting essentially of: a) based on the total weight of the composition, 0.1 to 15 wt% of an organic amine selected from 4-picoline N-oxide; 2-picoline N -oxide; 4-methoxypyridine N-oxide hydrate; 4-chloropyridine N-oxide; 8-methylquinoline N-oxide; N,N-dimethyl-N-oxide; 4-methylmorpholine 4-oxide; pyridine 1-oxide; b) 0.5 to 2 wt % of one or more inhibitors selected from benzotriazole (BTA) based on the total weight of said composition ; 5-alkylbenzotriazole (alkyl=-C _n H _2n+1 , where n=1-6); and 6-alkylbenzotriazole (alkyl=-C _n H _2n+1 , Wherein n=1-6); c) one or more buffering agents; d) based on the total weight of the composition, 0.01 to 3wt% of an activator selected from ammonium ethylenediaminetetraacetate; ethylenediaminetetra Tetraammonium acetate; tetraammonium trans-1,2-cyclohexylidenedinitrotetraacetate; ammonium diethylenetriaminepentaacetate; ammonium hydroxyethylethylenediamine triacetate; ammonium methylglycinate diacetate; Triammonium nitrilotriacetate; trans-1,2-cyclohexylenedinitrotetramethylammonium tetramethylammonium; tetramethylammonium ethylenediaminetetraacetic acid; e) based on the total weight of the composition , 10 to 50 wt% of one or more glycol ethers selected from butyl glycol (BG), butyl triethylene glycol, n-hexyl diglycol, n-hexyl glycol, 2-hexyloxy- 1-Ethanol, Tetrahydrofurfuryl Alcohol, Ethylene Glycol Monomethyl Ether, Ethylene Glycol Monoethyl Ether, Ethylene Glycol Monobutyl Ether, Ethylene Glycol Dimethyl Ether, Ethylene Glycol Diethyl Ether, Diethylene Glycol Monomethyl Ether, Di Ethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monoisopropyl ether, diethylene glycol monobutyl ether, diethylene glycol monoisobutyl ether, diethylene glycol dimethyl ether, diethyl Glycol diethyl ether, triethylene glycol monomethyl ether, triethylene glycol dimethyl ether, polyethylene glycol monomethyl ether, diethylene glycol methyl ethyl ether, triethylene glycol monomethyl ether acetate, Ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, propylene glycol dimethyl ether, propylene glycol monobutyl ether, propylene glycol, monopropyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoisopropyl ether, Propylene monobutyl ether, dipropylene glycol diisopropyl ether, tripropylene glycol monomethyl ether, 1-methoxy-2-butanol, 2-methoxy-1-butanol, 2-methoxy-2- Methylbutanol, 1,1-dimethoxyethane and 2-(2-butoxyethoxy)ethanol; f) 5 to 25% by weight of an aprotic solvent based on the total weight of the composition , which is selected from dimethylsulfoxide (DMSO), cyclobutylene, propylene carbonate; and g) water. According to the composition of claim 1, wherein the buffering agent can be selected from the following items: ammonium hydroxide; phosphoric acid; tetramethylammonium hydroxide (TMAH); tetraethylammonium hydroxide (TEAH); tetrabutylhydroxide Ammonium; Methanolamine (MEA); Ethanolamine (DEA); Triethanolamine (TEA); Polyethylene glycolamine; Diethyleneglycolamine; Triethyleneglycolamine; Hexahydrotriazine. The composition according to claim 2, wherein the buffering agent can be present in the composition of the present invention in an amount ranging from 0.01 to 5 wt%, based on the total weight of the composition. The composition according to claim 3, wherein the buffering agent can be present in the composition of the present invention in an amount ranging from 0.5 to 2 wt%, based on the total weight of the composition. The composition according to claim 1, wherein the activator can be present in the composition of the present invention in an amount ranging from 0.1 to 1 wt%, based on the total weight of the composition. The composition according to claim 1, which consists of the following: a) based on the total weight of the composition, 0.1 to 15 wt% of 4-methylmorpholine 4-oxide; b) based on the total weight of the composition 0.5 to 2 wt% of benzotriazole (BTA); c) one or more buffers; d) 0.01 to 3 wt% of trans-1,2-subcyclic Tetramethylammonium hexyl dinitrogen tetraacetate; e) based on the total weight of the composition, 15 to 45 wt% of diethylene glycol monobutyl ether; f) based on the total weight of the composition, 5 to 15 wt% dimethylsulfoxide (DMSO); and g) water. A use according to any one of claims 1 to 6 in combination with an oxidizing agent use for adjusting the etch rate of Cu/Co/Ru and TiN and/or removing organic and/or inorganic residues. The use according to claim 7, wherein the oxidizing agent can be selected from hydrogen peroxide (H ₂ O ₂ ), ozone water, and persulfuric acid. The use according to claim 8, wherein the oxidizing agent is hydrogen peroxide (H ₂ O ₂ ). Use according to claim 7, wherein said oxidizing agent can be mixed with said The volume ratio of the oxidizing agent) was added. The use according to claim 10, wherein said oxidizing agent can be mixed with said The volume ratio of the oxidizing agent) was added. Use according to claim 10, wherein the oxidizing agent can be mixed with the composition (the composition comprising components a) to g) in a volume ratio ranging from 22:1 to 1:1 (approximately from 1.5 to 16.2 wt%) The volume ratio of the oxidizing agent) is added. A kit comprising: the composition according to any one of claims 1 to 6; and an oxidizing agent. The kit according to claim 13, wherein the oxidizing agent can be selected from hydrogen peroxide (H ₂ O ₂ ), ozone water, persulfuric acid. The kit according to claim 14, wherein the oxidizing agent is hydrogen peroxide.

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