TW201439376A - Etching method for semiconductor substrate, etchant, manufacturing method for semiconductor device and etching kit - Google Patents

Abstract

An etching method is provided, wherein when a substrate including a first layer containing titanium nitride (TiN) and a second layer containing a transition metal is treated by using a single-wafer apparatus, an etchant having a pH of 1 or more and containing a specific fluorine compound and an oxidizing agent is contacted with the substrate to preferentially remove the first layer, and the specific fluorine compound is selected from metal salt and ammonium salt of hydrofluoric acid.

Description

Method for etching semiconductor substrate, method for manufacturing etching liquid and semiconductor element, and etching liquid set

The present invention relates to a method of etching a semiconductor substrate, an etching solution, a method of manufacturing a semiconductor device, and an etching solution set.

The miniaturization and diversification of semiconductor components are increasing, and the processing methods thereof involve many aspects along with the component structure or manufacturing steps. The etching of the substrate is also carried out in both dry etching and wet etching, and various chemicals or processing conditions are proposed depending on the type and structure of the substrate material.

Among them, it is important to precisely etch a predetermined material when fabricating a component structure such as a Complementary Metal Oxide Semiconductor (CMOS) or a Dynamic Random Access Memory (DRAM). One of the techniques may be a wet etching using a chemical. For example, in the production of a circuit wiring or a metal electrode material of a micro transistor circuit, or a substrate including a barrier layer or a hard mask, precise etching processing is required. However, including a variety of gold In the substrate of the compound, sufficient research has not been conducted on the etching conditions or chemicals suitable for the substrate. In this case, the effective removal of a hard mask or the like applied to the element substrate is a problem in manufacturing. Specifically, there is an example in which a chemical for etching titanium nitride (TiN) is studied (see Patent Document 1). ~ Patent Document 6).

[Previous Technical Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2005-097715

[Patent Document 2] Japanese Patent No. 4,896,995

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2009-021516

[Patent Document 4] Japanese Patent Laid-Open Publication No. 2009-019255

[Patent Document 5] Japanese Patent Laid-Open Publication No. 2009-044129

[Patent Document 6] US Patent Publication No. 2009017626

It is an object of the present invention to provide a first layer of titanium nitride (TiN) which exhibits selectivity with respect to a metal layer (second layer) and good in-plane uniformity, and also suppresses ruthenium oxidation. An etching method of a film (SiO ₂ layer), an etching liquid used in the etching method, a method of manufacturing a semiconductor element using the etching liquid, and an etching liquid set.

The above problems can be solved by the following means.

[1] An etching method for treating a substrate including a first layer containing titanium nitride (TiN) and a second layer containing a transition metal by using a one-chip device The etching solution containing a specific fluorine compound and an oxidizing agent having a pH of 1 or more is brought into contact with the substrate to preferentially remove the first layer, and the specific fluorine compound is selected from the group consisting of a metal salt of hydrofluoric acid and an ammonium salt of hydrofluoric acid. group.

[2] The etching method according to [1], wherein the transition metal is selected from the group consisting of Co, Ni, Cu, Ag, Ta, Hf, W, Pt, and Au.

[3] The etching method according to [1] or [2] wherein the specific fluorine compound is ammonium fluoride or tetramethylammonium fluoride.

[4] The etching method according to any one of [1] to [3] wherein the oxidizing agent is ammonium nitrate, nitric acid, methanesulfonic acid, perchloric acid, ammonium perchlorate or periodic acid.

[5] The etching method according to any one of [1] to [4] wherein the etching rate (R1) of the first layer is 20 Å/min or more and 600 Å/min or less.

[6] The etching method according to any one of [1] to [5] wherein the etching solution further contains at least one type of corrosion inhibitor selected from the group consisting of nitrogen-containing organic compounds and aromatic compounds.

[7] The etching method according to [6], wherein the corrosion inhibitor comprises a compound represented by any one of the following formulas (I) to (IX); [Chemical Formula 1]

(R ¹ to R ³⁰ each independently represent a hydrogen atom or a substituent; in this case, the adjacent members may be linked or condensed to each other to form a cyclic structure; A represents a hetero atom; wherein, when A is divalent; There is no R ¹ , R ³ , R ⁶ , R ¹¹ , R ²⁴ , R ²⁸ ) which are substituted here.

[8] The etching method according to [6] or [7], wherein the corrosion inhibitor is contained in a range of 0.01% by mass to 10% by mass.

[9] The etching method according to any one of [1], wherein the monolithic device includes a processing tank, and the semiconductor substrate is transferred or rotated in the processing tank, and is given in the processing tank. The etching solution brings the etching liquid into contact with the semiconductor substrate.

[10] The etching method according to any one of [1] to [9] wherein the specific fluorine compound is contained in an amount of from 0.001% by mass to 20% by mass.

[11] The etching method according to any one of [1] to [10] wherein the oxidizing agent is contained in an amount of 0.005 mass% to 30 mass%.

[12] The etching method according to any one of [1] to [11] wherein the pH exceeds 3 and is 7 or less.

[13] The etching method according to any one of [1] to [12] wherein the thickness of the first layer is 0.005 μm to 0.3 μm.

[14] The etching method according to any one of [1] to [13] wherein the etching liquid is prepared as a set including a first liquid containing a specific fluorine compound and a second liquid containing an oxidizing agent, It is used by mixing at an appropriate timing before contact with a semiconductor substrate.

[15] The etching method according to [14], wherein the temperature of the two liquids is adjusted to perform mixing.

[16] The etching method according to any one of [1], wherein the one-piece device includes a oscillating nozzle, and the nozzle is ejected while moving in a plane direction with respect to a surface of the semiconductor substrate. The etching solution is given.

[17] An etching solution for treating a substrate comprising a first layer containing titanium nitride (TiN) and a second layer containing a transition metal, comprising a hydrofluoric acid, using a monolithic device Metal salts and ammonium salts of specific fluorine compounds and oxidants.

[18] The etching solution according to [17], which comprises 0.001% by mass to 20% by mass of a specific fluorine compound.

[19] The etching solution according to [17] or [18] which contains 0.005 mass% to 30 mass% of an oxidizing agent.

[20] The etching solution according to any one of [17] to [19] wherein the pH is -1 to 7.

[21] The etching solution according to any one of [17] to [20] further comprising at least one corrosion inhibitor selected from the group consisting of nitrogen-containing organic compounds, aromatic compounds, and oxygen-containing organic compounds. .

[22] The etching solution according to any one of [17] to [21] further comprising a compound represented by any one of the following formulas (I) to (IX) as an anticorrosive agent;

(R ¹ to R ³⁰ each independently represent a hydrogen atom or a substituent; in this case, the adjacent members may be linked or condensed to each other to form a cyclic structure; A represents a hetero atom; wherein, when A is divalent; There is no R ¹ , R ³ , R ⁶ , R ¹¹ , R ²⁴ , R ²⁸ ) which are substituted here.

[23] A method of producing a semiconductor device, comprising: removing a first layer containing titanium nitride by an etching method according to any one of [1] to [16], and manufacturing a semiconductor element from a residual substrate .

[24] An etching solution set which is an etching liquid set including a first layer containing titanium nitride (TiN) and a second layer containing a transition metal, which comprises a monolithic device. The first liquid of the specific fluorine compound and the second liquid containing the oxidizing agent are mixed and used at an appropriate timing before the two liquids are brought into contact with the semiconductor substrate.

Etching the first layer containing TiN by the method of the present invention In this case, the selectivity to the metal layer (second layer) and good in-plane uniformity are exhibited, and damage to the tantalum oxide film can also be suppressed. Further, the surface of the TiN layer after etching can be made uniform (suppression of etching unevenness), and the surface after etching of the metal layer (second layer) can be made uniform.

The above and other features and advantages of the present invention will become more apparent from the description and appended claims.

1‧‧‧TiN layer (1st floor)

2‧‧‧SiON layer (3rd layer (1))

3‧‧‧SiOC layer (3rd layer (2))

4‧‧‧Cu/W layer (layer 2)

5‧‧‧through hole

10, 20‧‧‧ semiconductor substrate

11‧‧‧Processing container (treatment tank)

12‧‧‧Rotating table

13‧‧‧Spray outlet

14‧‧ ‧ Confluence

A, B‧‧‧ import port

‧‧‧Width

Fc‧‧‧Supply pipeline/flow path

Fd‧‧‧flow path

M‧‧‧Rotary Drive Department

R‧‧‧ direction

S‧‧‧Substrate

t‧‧‧Mobile track

1 is a cross-sectional view schematically showing an example of a manufacturing process (before etching) of a semiconductor substrate according to an embodiment of the present invention.

2 is a cross-sectional view schematically showing an example of a manufacturing process (after etching) of a semiconductor substrate according to an embodiment of the present invention.

3 is a view showing a configuration of a part of a wet etching apparatus according to a preferred embodiment of the present invention.

4 is a plan view schematically showing a movement trajectory of a nozzle with respect to a semiconductor substrate according to an embodiment of the present invention.

First, a preferred embodiment of the etching step of the etching method of the present invention will be described based on FIGS. 1 and 2.

[etching step]

FIG. 1 is a view showing a semiconductor substrate before etching. In the manufacturing example of the present embodiment, the SiOC layer 3 and the SiON layer 2 are disposed on a germanium wafer (not shown). For a specific third layer, a TiN layer 1 is formed on the upper side thereof. At this time, the through hole 5 is formed in the composite layer, and a second layer (metal layer) 4 containing metal is formed on the bottom of the through hole 5. The etching solution (not shown) of the present embodiment is applied to the substrate 10 in this state to remove the TiN layer. As a result, as shown in FIG. 2, the substrate 20 in a state where the TiN film is removed can be obtained. Needless to say, in the present invention or a preferred embodiment thereof, etching as shown in the drawing is preferable, but the residual of the TiN layer or the like may be suitably allowed depending on the required quality of the manufactured semiconductor element or the like. The second layer is slightly corroded and the invention is not limited by the description.

Further, in the case of a germanium substrate or a semiconductor substrate, or simply a substrate, it is used in the following sense: not only a germanium wafer, but also a substrate structure in which a circuit structure is implemented. The member of the substrate refers to a member constituting the above-described ruthenium substrate, and may include one material or a plurality of materials. The processed semiconductor substrate is sometimes referred to differently as a semiconductor substrate product. The wafer and its processed product which are further processed as needed, and which are cut and taken out are referred to as a semiconductor element or a semiconductor device. The orientation of the substrate is not particularly limited. In FIG. 1, the opposite side (TiN side) of the germanium wafer is referred to as "upper", and the germanium wafer side (SiOC side) is referred to as "lower". Or "bottom."

[etching solution]

Next, a preferred embodiment of the etching liquid of the present invention will be described. The etching liquid of the present embodiment contains an oxidizing agent and a specific fluorine compound. Hereinafter, each component will be described, including any one.

(oxidant)

Examples of the oxidizing agent include ammonium nitrate, nitric acid, methanesulfonic acid, perchloric acid, ammonium perchlorate, periodic acid, a combination thereof, and the like. Among them, ammonium nitrate and nitric acid are preferred. The best is ammonium nitrate. When hydrogen peroxide is used as the oxidizing agent, there is a phenomenon that the stability over time cannot be ensured. In this regard, since the above oxidizing agent is used in the present invention, it is stable and stable in manufacturing quality, and can be suitably applied to storage, storage, and the like in a circulation system.

With respect to the total mass of the etching liquid of the present embodiment, it is preferable to contain The oxidizing agent is 0.005% by mass or more, more preferably 0.01% by mass or more, and particularly preferably 0.1% by mass or more. The upper limit is preferably 30% by mass or less, more preferably 20% by mass or less, still more preferably 15% by mass or less, particularly preferably 10% by mass or less, and still more preferably 8% by mass or less. It is 5% by mass or less. When the value is equal to or less than the above upper limit value, it is possible to further suppress excessive etching of the second layer (damage to metals containing TiN and Si, Al, etc.), which is preferable. From the viewpoint of etching the first layer at a sufficient speed, it is preferable to set it as the above lower limit value or more. Further, by adjusting the amount to an appropriate range, it is possible to further effectively improve the etching selectivity of the first layer.

These oxidizing agents may be used alone or in combination of two or more.

(specific fluorine compounds)

The specific fluorine compound is a compound indicating a metal salt and an ammonium salt selected from hydrofluoric acid. Specific examples thereof include alkali metal fluoride salts (NaF, KF, etc.), hydrofluoric acid salts of amines (monoethylamine hydrofluoric acid, triethylamine trihydrofluoric acid, etc.), pyridine hydrofluoric acid, and fluorination. Ammonium, tetraalkylammonium fluoride (tetramethylammonium fluoride, tetra-n-butylammonium fluoride, etc.). Preferred It is ammonium fluoride or tetraalkylammonium fluoride (tetramethylammonium fluoride). In the present invention, as described above, the supply source of the active fluoride ion in the etching liquid is not only hydrofluoric acid but also a metal salt or an ammonium salt. As a result, the liquid physical properties such as pH can be stably adjusted in an appropriate region, whereby high etching property of TiN can be maintained, and etching (damage) of the second layer (transition metal layer) can be suppressed. In the present invention, the "salt" of hydrofluoric acid is further applied, so that it has sufficient etching ability and can maintain stable chemical activity. Further, it is advantageous in terms of easy adjustment of concentration and safety. Moreover, the neutralization treatment can be omitted, so that heat generation in the system due to the neutralization reaction can be suppressed, which is advantageous for manufacturing suitability.

With respect to the total mass of the etching liquid of the present embodiment, it is preferable to contain 0.001% by mass or more of the specific fluorine compound, more preferably 0.005% by mass or more, still more preferably 0.01% by mass or more, still more preferably 0.05% by mass or more, and particularly preferably 0.1% by mass. the above. The upper limit is preferably 20% by mass or less, more preferably 10% by mass or less, still more preferably 5% by mass or less, still more preferably 3% by mass or less, and particularly preferably 1.5% by mass or less. % or less, particularly preferably 1% by mass or less. By setting the concentration to be equal to or higher than the lower limit value, it is preferable to maintain the dissolution rate of TiN at a high level. On the other hand, it is preferable that the damage to the insulating layer is not excessively large by setting it as the said upper limit or less.

In relation to the oxidizing agent, relative to 100 parts by mass of the oxidizing agent In particular, it is preferred to use 0.1 part by mass or more of the specific fluorine compound, and more preferably 1 part by mass or more. The upper limit is preferably 10,000 parts by mass or less, more preferably 1000 parts or less. Below the mass part, it is particularly preferably 500 parts by mass or less. By using the amounts of both in an appropriate relationship, good etching properties can be achieved, and high in-plane uniformity is achieved at the same time.

The above specific fluorine compounds may be used alone or in combination of two or more.

(corrosion inhibitor)

In the etching liquid of the present invention, it is preferable to contain an anticorrosive agent having the corrosion resistance of the second layer and improving the uniformity thereof. By adding it, the uniformity of the surface of the first layer after etching (the effect of suppressing uneven etching) can be improved. By making the etching uniformity as described above, it is possible to improve the residual unevenness of etching. By improving the surface uniformity of the laminated metal layer (the second layer), the surface uniformity of the first layer (TiN layer) can be achieved, and the manufacturing steps can be compared with those having uniformity alone. The improvement and the improvement of manufacturing quality have contributed greatly. Moreover, the corrosion inhibitor can also exert an effect of preventing surface defects of the TiN layer.

. Nitrogen-containing organic compounds/aromatic compounds

The corrosion inhibitor is preferably a nitrogen-containing organic compound, preferably a nitrogen-containing heterocyclic compound of 5 or 6 members (heteroatoms are nitrogen, oxygen, sulfur, etc.). Alternatively, an aromatic compound is preferred. The heterocyclic compound and the aromatic compound may be monocyclic or polycyclic. More preferably, the heterocyclic compound is a 5-membered nitrogen-containing heterocyclic aromatic compound. The content of nitrogen at this time is preferably from 1 to 4. The aromatic compound is preferably a compound having a benzene ring.

The corrosion inhibitor is preferably a compound represented by any one of the following formulas (I) to (IX).

. R ¹ ~R ³⁰

In the formula, R ¹ to R ³⁰ each independently represent a hydrogen atom or a substituent. The substituent may be an alkyl group (preferably having a carbon number of 1 to 20, more preferably 1 to 6) or an alkenyl group (preferably, the carbon number is 2 to 20, more preferably 2 to 6). , an aryl group (preferably having a carbon number of 6 to 22, more preferably 1 to 14), a heterocyclic group (preferably having a carbon number of 1 to 20, more preferably 1 to 6), and an alkane An oxy group (preferably having a carbon number of 1 to 20, more preferably 1 to 6), a sulfhydryl group (preferably having a carbon number of 2 to 20, more preferably 2 to 6), and an amine group (more preferably Preferred are a carbon number of 0 to 6), a carboxyl group, a phosphoric acid group, a hydroxyl group, a mercapto group (-SH), and a boric acid group (-B(OH) ₂ ). Further, the above aryl group is preferably a phenyl group or a naphthyl group. The above heterocyclic group may, for example, be a nitrogen-containing heterocyclic aromatic group, and among them, a 5-membered nitrogen-containing heterocyclic aromatic group is preferred, and a pyrrolyl group, an imidazolyl group, a pyrazolyl group, a triazolyl group or a tetra is more preferred. Azolyl. These substituents may further have a substituent within the range which exerts the effect of the present invention. Further, among the above substituents, an amine group, a carboxyl group, a phosphoric acid group or a boric acid group may form a salt thereof. Examples of the counter ion to form a salt include a quaternary ammonium such as an ammonium ion (NH ₄ ⁺ ) or a tetramethylammonium ion ((CH ₃ ) ₄ N ⁺ ).

The above substituent may be substituted via any linking group. The linker The alkylene group (preferably having a carbon number of 1 to 20, more preferably 1 to 6), an alkenyl group (preferably having a carbon number of 2 to 20, more preferably 2 to 6), An ether group (-O-), an imido group (preferably having a carbon number of 0 to 4), a thioether group (-S-), a carbonyl group, or a combination thereof. Hereinafter, the linking group will be referred to as a linking group L. Further, the linking group may further have a substituent within the range in which the effects of the present invention are exerted.

Preferred among R ¹ to R ³⁰ are an alkyl group having 1 to 6 carbon atoms, a carboxyl group, an amine group (preferably having a carbon number of 0 to 4), a hydroxyl group, or a boronic acid group. These substituents may also be substituted via the linking group L as described above.

Further, R ¹ to R ³⁰ may be joined or entangled with each other to form a ring structure. Examples of the ring structure to be formed include a nitrogen-containing heterocyclic ring structure, and examples thereof include a pyrrole ring structure, an imidazole ring structure, a pyrazole ring structure, and a triazole ring structure. Further, the ring structure may further have a substituent within the range in which the effects of the present invention are exerted. Further, when the ring structure formed here is a benzene ring, the formula (VII) is classified and arranged.

. A

A represents a hetero atom and represents a nitrogen atom, an oxygen atom, a sulfur atom, or a phosphorus atom. However, when A is a divalent (oxygen atom or a sulfur atom), R ¹ , R ³ , R ⁶ , R ¹¹ , R ²⁴ and R ^{28 are not present} .

The compound represented by the above formula (VII) is preferably the following formula (VII-1) Any of the formulae of the formula (VII-4).

R ^a represents an acidic group, preferably a carboxyl group, a phosphoric acid group, or a boronic acid group. The acidic group may be substituted via the linking group L described above.

R ^b is an alkyl group having 1 to 6 carbon atoms, an amine group (preferably having a carbon number of 0 to 4), a hydroxyl group, an alkoxy group (preferably having a carbon number of 1 to 6), or a mercapto group ( Preferably, the carbon number is from 1 to 6). The substituent R ^b may be substituted via the linking group L described above. When having a plurality of R ^b , these may also be linked or condensed to form a ring structure.

N1 is an integer from 1 to 5. N2 is an integer from 0 to 5. N3 is an integer from 0 to 4. When n1 to n3 are each 2 or more, the plurality of substituents defined herein may be the same or different.

Wherein A is synonymous with A as defined above. R ^c , R ^d , and R ^e are groups synonymous with R ¹ to R ³⁰ . However, when A is divalent, there is no R ^c and R ^e .

The following shows the formula represented by any of the above formulas (I) to (IX). Examples of the compound, but the invention is not limited thereto.

Further, examples of the tautomers are included in the following exemplified compounds, and other tautomers are also included in the preferred examples of the present invention. About the above formula (I)~ Formula (IX), Formula (VII-1) to Formula (VII-4) are also the same.

The content of the nitrogen-containing organic compound or the aromatic compound forming the corrosion inhibitor is not particularly limited, but is preferably 0.01% by mass or more in the etching solution, and more preferably It is 0.05 mass% or more, and particularly preferably 0.1 mass% or more. The upper limit is not particularly limited, but is preferably 10% by mass or less, more preferably 5% by mass or less, still more preferably 3% by mass or less, and particularly preferably 1% by mass or less. It is preferable to set it as the said lower limit or more, and can acquire the suitable uniformization effect and a defect prevention effect. On the other hand, from the viewpoint of not impeding good etching performance, it is preferably set to be equal to or less than the above upper limit.

The above-mentioned nitrogen-containing organic compound/aromatic compound may be used alone or in combination of two or more.

In the present specification, each of the technical matters such as temperature and thickness represented by the selective limb of the compound or the linking group is independently described, but may be combined with each other.

(aqueous medium)

In the etching liquid of the present invention, it is preferred to use water (aqueous medium) as the medium, and it is preferred to each contain an aqueous solution in which the components are uniformly dissolved. The content of water is preferably 50% by mass to 99.5% by mass, and more preferably 55% by mass to 95% by mass based on the total mass of the etching liquid. As described above, a composition containing water as a main component (50% by mass or more) is particularly referred to as a water-based composition, and is relatively inexpensive compared with a composition having a high ratio of an organic solvent, and is suitable for the environment. Better words. From this viewpoint, the etching liquid of the present invention is preferably a water-based composition. The water (aqueous medium) may be an aqueous medium containing a dissolved component in a range that does not impair the effects of the present invention, or may contain an unavoidable minute mixed component. Among them, distilled water, ion-exchanged water, or ultrapure water, etc., which has been subjected to purification treatment, is particularly preferred. Ultrapure water used in semiconductor manufacturing.

(pH)

In the present invention, the pH of the etching solution is adjusted to -1 or more or 1 or more, more preferably more than 3, still more preferably 3.5 or more, and particularly preferably 4 or more. The upper limit is preferably set to 10 or less, more preferably 9 or less, still more preferably 7 or less, still more preferably 6 or less, and particularly preferably 5 or less. the following. In order to make the etching rate of TiN practical, and to improve the in-plane uniformity, it is preferable to set it as the said lower limit or more. On the other hand, when it is set to the above upper limit or less, it is preferable because it is resistant to other substrates such as SiO or SiOC.

(other ingredients)

. pH adjuster

In the present embodiment, it is preferable to use the pH adjuster for the adjustment in which the pH of the etching liquid is in the above range. The pH adjuster is preferably a quaternary ammonium salt such as tetramethylammonium or choline, an alkali hydroxide or alkaline earth salt such as potassium hydroxide or an amine compound such as 2-aminoethanol or hydrazine for increasing the pH. In order to lower the pH, inorganic acids such as hydrochloric acid, nitric acid, sulfuric acid, and phosphoric acid, or formic acid, acetic acid, propionic acid, butyric acid, valeric acid, 2-methylbutyric acid, n-hexanoic acid, and 3,3-dimethylbutyric acid may be mentioned. , 2-ethylbutyric acid, 4-methylpentanoic acid, n-heptanoic acid, 2-methylhexanoic acid, n-octanoic acid, 2-ethylhexanoic acid, benzoic acid, glycolic acid, salicylic acid, glyceric acid, oxalic acid , malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, maleic acid, phthalic acid, malic acid, tartaric acid, citric acid, lactic acid and other organic acids.

The amount of the pH adjuster used is not particularly limited, in order to adjust the pH to the above-mentioned range Use the necessary amount.

(set)

The etching liquid of the present invention may be a set in which a raw material is divided into a plurality of sets. For example, a liquid composition containing the specific fluorine compound in an aqueous medium is prepared as a first liquid, and a liquid composition containing the oxidizing agent in an aqueous medium is prepared as a second liquid. As an example of use, it is preferred to mix the two liquids to prepare an etching liquid, and then apply it to the above-described etching treatment at an appropriate timing. By doing so, it is possible to effectively exhibit the desired etching action without causing deterioration in liquid properties due to decomposition of the respective components. Here, the term "appropriate timing" after mixing refers to a period until the desired effect is lost after mixing, and specifically, it is preferably within 60 minutes, more preferably within 30 minutes, and particularly preferably for 10 minutes. Within. The lower limit is not particularly limited, and is actually 1 second or longer.

The concentration of the specific fluorine compound in the first liquid is not particularly limited, but is preferably 1.0% by mass or more, and more preferably 2.0% by mass or more. The upper limit is preferably 10% by mass or less, and more preferably 5% by mass or less. By setting the concentration to the above range, it is preferable to be in a state suitable for mixing with the second liquid, and it is preferable to use a suitable concentration region in the etching liquid.

The concentration of the oxidizing agent in the second liquid is not particularly limited, but is preferably 10% by mass or more, and more preferably 20% by mass or more. The upper limit is preferably 50% by mass or less, and more preferably 40% by mass or less. By setting the concentration to the above range, it is preferable to be in a state suitable for mixing with the first liquid, and it is preferable to use a suitable concentration region in the etching liquid.

In the case of using the above-mentioned corrosion inhibitor, it is preferable to add it to the first one in advance. Liquid side. Alternatively, a liquid composition containing a water-soluble organic solvent in an aqueous medium may be prepared and mixed as the third liquid with the first liquid and the second liquid.

The method of mixing the first liquid and the second liquid is not particularly limited, but it is preferred to The first liquid and the second liquid flow in the respective flow paths, and the two are joined at the junction point and mixed. Thereafter, it is preferable to further flow the flow path, and to eject or spray the etching liquid obtained by the flow from the discharge port to be in contact with the semiconductor substrate. In the embodiment, the process of mixing from the junction at the junction to the contact with the semiconductor substrate is preferably performed at the "appropriate timing" described above. As will be described with reference to Fig. 3, the prepared etching liquid is ejected from the ejection port 13 and applied to the upper surface of the semiconductor substrate S in the processing container (processing tank) 11. In the embodiment shown in the same figure, the two liquids A and B are supplied, merged at the joining point 14, and then moved to the discharge port 13 via the flow path fc. The flow path fd represents a return path for recycling chemicals. The semiconductor substrate S is located on the turntable 12, and preferably rotates together with the turntable by the rotary drive portion M. Further, an embodiment using such a substrate rotary device can be similarly applied to a process using an etching liquid which is not formed into a jacket.

Further, as the etching liquid of the present invention, it is preferable that impurities such as a metal component in the liquid are small in view of the use thereof.

(container)

The etching liquid of the present invention (whether or not it is a set) can be stored in a container, stored, and used as long as it does not cause problems such as corrosion resistance. Moreover, in order to be used for semiconductor applications, it is preferred that the container has high cleanliness and impurities are dissolved. The lesser. As the container which can be used, a "Clean Bottle" series manufactured by Aicello Chemical Co., Ltd., KODAMA PLASTICS Co., Ltd., can be cited. The "Pure Bottle" manufactured, etc., is not limited to these.

[etching conditions]

In the etching method of the present invention, it is necessary to use a monolithic device. Specifically, the monolithic device preferably includes a processing tank in which the semiconductor substrate is transferred or rotated, and the etching liquid is supplied to the processing tank to cause the etching liquid and the semiconductor. The substrate is in contact.

The advantages of the one-piece device are as follows: (i) the fresh etching liquid is always supplied, so that the reproducibility is good; and (ii) the in-plane uniformity is high. Further, it is easy to use a method in which the etching liquid is divided into a plurality of sets, and for example, a method in which the first liquid and the second liquid are mixed in a line and discharged is used. In this case, it is preferable to adjust the temperature of the first liquid and the second liquid together, or to adjust the temperature of only one of the liquids, and to mix and eject them in the line. Among them, an embodiment in which temperature adjustment is performed together is more preferable. The management temperature at the time of temperature adjustment of the pipeline is preferably set to the same range as the processing temperature described later.

The monolithic device preferably includes a nozzle in the processing tank, and preferably a method in which the nozzle is swung in the surface direction of the semiconductor substrate to eject the etching liquid onto the semiconductor substrate. It is preferable to prevent deterioration of the liquid by performing as described above. Further, it is preferable to divide it into two or more liquids by setting it as a kit, and it is possible to make it difficult to generate a harmful gas or the like. In particular, the present invention is used when heating an etchant or a first liquid which is separated therefrom effective. Specifically, even if the liquid is heated, the fluorine compound is introduced as a salt, and therefore it is stable as described above, and has an advantage that it is difficult to cause liquid deterioration.

Further detailed description of the conditions, a preferred implementation of the present invention In the monolithic device, the semiconductor substrate is transferred or rotated in a predetermined direction, and an etching liquid is supplied (discharged, ejected, flowed, dropped, etc.) in the space to bring the etching liquid into contact with the semiconductor substrate.

As for the ambient temperature at which etching is performed, the temperature shown in the examples described later The measurement method is preferably 40 ° C or higher, more preferably 50 ° C or higher, and particularly preferably 55 ° C or higher. The upper limit is preferably 80 ° C or lower, more preferably 70 ° C or lower. By setting it as the said lower limit or more, it is preferable to ensure the sufficient etching rate with respect to a TiN layer. By setting it as the said upper limit or less, it is preferable to maintain the time-lapse stability of the etching process speed. The supply rate of the etching liquid is not particularly limited, but is preferably 0.05 L/min to 5 L/min, more preferably 0.05 L/min to 1 L/min, and particularly preferably 0.1 L/min. ~0.5L/min. By setting it as the said lower limit or more, the in-plane uniformity of etching can be improved favorably, and it is preferable. By setting it as the said upper limit or less, it is good in the stable process, and it is preferable. In order to rotate the semiconductor substrate, the size of the semiconductor substrate is preferably 50 rpm to 1000 rpm, and more preferably 50 rpm to 600 rpm, from the viewpoint of the above.

In the monolithic etching of the preferred embodiment of the present invention, it is preferred that The semiconductor substrate is transferred or rotated in a predetermined direction, and an etching liquid is ejected in the space to bring the etching liquid into contact with the semiconductor substrate. About the supply speed of the etching solution or The rotation speed of the substrate is the same as described above.

In the monolithic device configuration of the preferred embodiment of the present invention, It is preferable to apply an etching liquid while moving the discharge port (nozzle) as shown in Fig. 4 . Specifically, in the present embodiment, when an etching liquid is applied to the semiconductor substrate S including the TiN layer, the substrate is rotated in the r direction. On the other hand, the ejection port is moved along the movement trajectory t extending from the central portion of the semiconductor substrate toward the end portion. As described above, in the present embodiment, the rotation direction of the substrate and the movement direction of the discharge port are set to be different directions, thereby causing the two to move relative to each other. As a result, the etching liquid can be uniformly applied to the entire surface of the semiconductor substrate, and the etching uniformity can be appropriately ensured.

The moving speed of the discharge port (nozzle) is not particularly limited, but is preferably 0.1 cm/s or more, and more preferably 1 cm/s or more. On the other hand, the upper limit is preferably 30 cm/s or less, more preferably 15 cm/s or less. The moving trajectory can be a straight line or a curved line (for example, an arc shape). In any case, the moving speed can be calculated from the distance of the actual trajectory line and the time it takes to move.

[residue]

In the manufacturing process of the semiconductor element, there may be a step of etching a metal layer or the like on the semiconductor substrate by plasma etching using a resist pattern or the like as a mask. Specifically, the metal layer, the semiconductor layer, the insulating layer, and the like are etched to pattern the metal layer or the semiconductor layer, or an opening such as a via hole or a wiring trench is formed in the insulating layer. In the plasma etching described above, a residue derived from a resist used as a mask or a metal layer, a semiconductor layer, or an insulating layer to be etched is generated on the semiconductor substrate. In the present invention In the above, the residue generated by plasma etching as described above is referred to as "plasma etching residue". Further, the "plasma etching residue" also includes an etching residue of the third layer (SiON or SiOC).

Moreover, the resist pattern used as a mask is removed after etching. Resist In the removal of the pattern, as described above, a wet method using a stripper solution or a dry method using, for example, ashing using plasma, ozone or the like is used. In the above ashing, a residue which is deteriorated by the plasma etching residue due to plasma etching or a residue derived from the removed resist is generated on the semiconductor substrate. In the present invention, the residue generated by ashing as described above is referred to as "ashing residue". In addition, the general name of the plasma etching residue and the ashing residue which are required to be cleaned and removed on the semiconductor substrate may be simply referred to as "residue".

Electrostatic erosion as a post-etch residue (Post Etch Residue) The residue or ash residue is preferably washed and removed using a cleaning composition. The etching solution of the present embodiment can also be applied as a cleaning liquid for removing plasma etching residue and/or ashing residue. Among them, it is preferred to remove the plasma etching residue and the ash residue after the plasma ashing continues after the plasma etching.

[processed object]

The material to be etched by applying the etching liquid of the present embodiment may be any material, and a substrate including the first layer containing TiN is applied. Here, the TiN-containing layer (TiN layer) may contain oxygen, and may be referred to as a TiON layer or the like when it is distinguished from a layer containing no oxygen. In the present invention, the oxygen content of the TiN layer is preferably 10 mol% or less, more preferably 8.5 mol% or less, still more preferably 6.5. Mol% or less. The lower limit is preferably 0.1 mol% or more, more preferably 2.0 mol% or more, still more preferably 4.0 mol% or more.

The adjustment of the oxygen concentration in the TiN layer of the substrate can be performed, for example, by adjusting the oxygen concentration in the chemical vapor deposition (CVD) process chamber in the formation of the TiN layer. Further, the first layer contains TiN as its main component, but may contain other components in the range in which the effects of the present invention are exerted. Other layers such as the second metal layer are also the same.

In the present specification, the surface oxygen concentration of the TiN layer is measured by etching ESCA (Quantera manufactured by ULVAC-PHI) to measure the concentration distributions of Ti, O, and N in the depth direction of 0 nm to 30 nm, and the content ratios of 5 nm to 10 nm are calculated, respectively. The average oxygen content rate was taken as the surface oxygen concentration.

Preferably, the first layer is etched at a high etch rate. The thickness of the first layer is not particularly limited, and when considering a normal element configuration, it is actually about 0.005 μm to 0.3 μm. The etching rate [R1] of the first layer is not particularly limited, and in view of production efficiency, it is preferably 20 Å/min or more, more preferably 50 Å/min or more, and particularly preferably 70 Å/min or more. The upper limit is not particularly limited and is actually 600 Å/min or less.

The method of the present invention is preferably applied to a semiconductor substrate comprising a second layer containing a metal such as Cu, W, Co, Ni, Ag, Ta, Hf, Pt or Au. Among them, it is preferred to use Cu and W as the material of the second layer.

Here, the meaning of the technique of the metal layer will be described based on the case where copper (Cu) and tungsten (W) are used as the material. In recent years, dealing with semiconductor components (half The high speed of the conductor device, the miniaturization of the wiring pattern, and the demand for high integration require reduction in capacitance between wirings, improvement in conductivity of wiring, and improvement in electromigration resistance. As a technique for coping with these requirements, a multilayer wiring technique using a low dielectric constant layer (Low-k layer) as an interlayer insulating layer is used as a wiring material using copper having high conductivity and excellent electromigration resistance as a wiring material. The copper wiring is generally disposed on a copper seed layer (for example, a double layer of tantalum (Ta) and tantalum nitride (TaN)) by a dual damascene process, and the copper seed layer serves as a copper for preventing the copper wiring. The diffused copper diffusion prevents the film from functioning.

On the other hand, the contacts of semiconductor components are typically via single metal damascene The process is provided instead of a tungsten plug made by a dual damascene process used for forming copper wiring and via holes. In such a multilayer wiring technique, a damascene method in which a recess such as a wiring trench or a through hole is formed in a low dielectric constant layer and copper is buried therein is used. In this case, in order to form the concave portion with high precision by etching in the low dielectric constant layer, it is necessary to use a mask including a material having a sufficiently high selectivity to the low dielectric constant layer as the etching of the low dielectric constant layer. The mask.

The above low dielectric constant layer generally uses an organic material, so the package is When the photoresist layer containing the same organic material is used as a mask to etch the low dielectric constant layer, the selection ratio is insufficient. In order to solve such a problem, it has been proposed to use a hard mask layer containing an inorganic material such as a TiN film as a mask for etching. Moreover, it becomes necessary to remove the hard mask layer by a process after etching the low dielectric constant layer. In particular, in the etching of a wet process, it is desirable to form the hard mask without etching a metal layer such as a tungsten plug or other wiring or a low dielectric constant layer material. Surely removed.

In the above-described form, in order to form the first layer of the hard mask The (TiN) layer is removed. In this case, the metal layer (the second layer) is usually located at the bottom of the via hole or trench (see FIGS. 1 and 2).

The etching rate [R2] of the second layer (metal layer) is not particularly limited, and is preferably It is not excessively removed, and is preferably 10 Å/min or less. The lower limit is not particularly limited, and in consideration of the measurement limit, it is actually 0.1 Å/min or more.

Etching rate ratio ([R1]/[R2]) in the selective etching of the first layer It is not particularly limited, and it is preferably 2 or more, more preferably 3 or more, and still more preferably 5 or more, on the premise that an element requiring high selectivity is used. There is no special limit on the upper limit. The higher the better, the fact is 100 or less.

The exposed width of the metal layer (d in the figure) is not particularly limited, since the present invention From the viewpoint of the advantage that the advantage becomes more remarkable, it is preferably 2 nm or more, and more preferably 4 nm or more. Similarly, from the viewpoint of the significance of the effect, the upper limit is actually 1000 nm or less, preferably 100 nm or less, and more preferably 20 nm or less.

Further, the method of the present invention is also preferably applied to a semiconductor substrate comprising a third layer containing a metal compound such as SiO, SiN, SiOC or SiON. In addition, in the present specification, when the composition of the metal compound is described by a combination of elements of a metal compound, the meaning of any constituent is widely included. For example, SiO is a thermal oxide film of ruthenium and contains SiO ₂ and contains SiOx. It is shared in this specification and is the same for other metal compounds. Regarding the third layer, it is preferred that surface uniformity is also performed. The etching rate [R3] of the third layer is not particularly limited, and is preferably the same as the etching rate [R2] of the second layer. The ratio of the etching rate of the third layer to the etching rate of the first layer ([R1]/[R3]) is also the same as the preferred range of the second layer ([R1]/[R2]).

[Manufacture of semiconductor substrate products]

In the present embodiment, it is preferable to manufacture a semiconductor substrate product having a desired structure by a step of forming a semiconductor substrate on which a first layer and a second layer are formed on a germanium wafer; The step of applying the etching solution to the substrate to selectively dissolve the first layer. At this time, the above specific etching liquid is used in etching.

[Examples]

Hereinafter, the present invention will be described in more detail by way of examples, but the invention is not limited to the following examples.

In addition, the specification of the quantity or ratio shown in an Example is a mass basis unless it demonstrates especially.

<Example 1 and Comparative Example 1>

The composition (% by mass) shown in each table contains the components shown in the following table to prepare an etching solution. The rest is water (ultra-pure water).

(Method of manufacturing TiN substrate)

A TiN film having a surface oxygen concentration of 6.0 mol% was formed by CVD on a commercially available tantalum substrate. Further, according to a known method, a metal layer in the surface was formed beside the TiN layer to prepare a test substrate.

(etching test)

For the above test substrate, by a single-chip device (SPS-Europe B.V. The company manufactured and POLOS (trade name) were etched under the following conditions to carry out an evaluation test.

. Processing temperature: 57 ° C

. Spraying amount: 1L/min.

. Wafer speed is 500rpm

Further, the supply of the etching liquid can be divided into two liquids as described below and carried out by in-line mixing (see FIG. 3). The supply line fc can be temperature-controlled at 60 ° C by heating.

The first liquid: fluorine compound and water

2nd liquid: oxidant and water (anti-corrosion agent if necessary)

The ratio of the first liquid to the second liquid is equal to the volume. Among them, one component in the comparative example was supplied as one liquid.

(Method for measuring treatment temperature)

A radiation thermometer IT-550F (trade name) manufactured by Horiba, Ltd. was fixed to a height of 30 cm on the wafer in the above-described single chip device. The thermometer was placed on the surface of the wafer 2 cm outside from the center of the wafer, and the temperature was measured while flowing chemicals. The temperature is output from the radiation temperature counter bit and continuously recorded by a personal computer. Among them, the temperature at which the temperature was stable for 10 seconds was averaged and the obtained value was taken as the temperature on the wafer.

(pH)

The pH was measured at room temperature (25 ° C) using F-51 (trade name) manufactured by HORIBA.

(etching speed)

The etching rate (ER) of the TiN layer was evaluated as follows. The etching rate (ER) was calculated by measuring the film thickness before and after the etching treatment using an ellipsometry (Spectroscopic ellipsometer, J.A. Woollam Japan Co., Inc., using Vase (trade name)). The average value of 5 points was used (measurement conditions: measurement range: 1.2 eV to 2.5 eV, measurement angle: 70 degrees, 75 degrees).

(SiOx damage)

The damage of the SiO ₂ layer was evaluated by its etching rate (ER). A substrate having ruthenium oxide (thermal oxide film) formed on a crucible at a thickness of 1000 nm was used, and the other substrates were treated in the same manner.

A: 10Å/min or less

B: more than 10Å/min and less than 50Å/min

C: more than 50Å/min or more

The test starting with C is a comparative example (the same is true for the following table).

The values shown under the metal or metal compound names in the table are the etching rates (Å/min).

According to the above results, it is understood that the etching selectivity of TiN is preferentially removed by the etching liquid of the present invention, and the protective property of the tantalum oxide film is excellent.

(Example 2, Comparative Example 2)

An etching test was performed in the same manner as in Example 1 except that the concentration of the additive used was changed as shown in Tables 2 to 6. The results are shown in Tables 2 to 6.

BTA: benzotriazole (Compound No. VII-2-1)

The pH is adjusted by ammonia water or sulfuric acid.

TMAF: Tetramethylammonium fluoride

According to the above results, it can be seen that the present invention can be widely used for various components. Appropriate performance is obtained in the range of pH and pH. Moreover, further higher selectivity can be exerted by appropriately adjusting the concentration or pH as needed. Moreover, even if the form of the oxidizing agent or the salt containing the fluorine compound is changed, the desired performance can be exhibited.

(Example 3)

An etching test was performed in the same manner as in Example 1 except that the corrosion inhibitors in Table 7 below were used. The results are shown in Table 7.

From the above results, it is understood that by the present invention, an anticorrosive agent is applied as needed, whereby further higher etching selectivity can be exhibited.

(Example 4)

An etching test was performed in the same manner as in Example 1 except that the etching conditions in Table 8 below were applied. The results are shown in Table 8. In addition, the two types of liquids are prepared as follows (SWT (2)), and two kinds of liquids are prepared as follows, and are supplied through the inlet A and the inlet B shown in FIG. The supply line fc is temperature-controlled at 60 ° C by heating. One liquid is supplied through the inlet port A.

The first liquid: fluorine compound and water

2nd liquid: oxidant and water (anti-corrosion agent if necessary)

The ratio of the first liquid to the second liquid is equal to the volume.

Temperature management of the pipeline can be carried out as follows. The nichrome wire insulated from the stainless steel pipe through which the etching liquid flows is circumferentially heated, and a thermocouple is inserted between the pipe and the nichrome wire to measure the temperature. The heating of the circulating etching liquid is performed before the mixing of the first liquid and the second liquid by a heating tank (not shown) in the line. At this time, control is performed so as to stably become a predetermined temperature based on the above-described measured temperature.

(note of the table)

. SWT: Monolithic device

POLOS (product name) manufactured by SPS-Europe B.V.

(1) Etching solution for 1 liquid (after 12 hours after modulating the liquid)

(2) On-line mixing of the two-liquid set and application

. BT: Batch device

濑戸Technology Industrial Co., Ltd. Manual wet table (product name). Swing speed... gives the swing speed of the chemical discharge port (see Figure 4). Water cleaning: using ultrapure water after etching

Continuous rinsing (Yes)

The above continuous flushing (No)

From the above results, it is understood that the present invention using a monolithic device exhibits appropriate performance with respect to selective etching of TiN. In particular, in a one-piece device, high in-plane uniformity can be exhibited.

Further, the defect performance and in-plane uniformity in the above table can be evaluated as described below.

[Defect performance evaluation]

The surface of the etched wafer was observed by a defect inspection device (trade name: SP-1, manufactured by KLA-Tencor), and the number of residues of TiN on the surface was evaluated. The case where the residue of 0.2 μm or more was present was measured as one defect number.

The number of defects above 0.2 μm is

A: less than 50 / 12 吋 wafer surface;

B: 50 or more and less than 200 / 12 吋 wafer surface;

C: More than 200/12” wafer faces.

[In-plane uniformity evaluation of 12-inch wafer]

The condition was set by changing the time, and it was confirmed that the etching depth of the center of the circular substrate (diameter 12 吋) was 300 Å. Next, when the entire substrate was etched again at this time, the etching depth from the periphery of the substrate to the center direction of 30 mm was measured, and the depth was closer to 300 Å, and the in-plane uniformity was evaluated to be high. The specific distinction is as follows. The measurement position at this time was set to 10 each, and it evaluated by the average value. Regarding the metal layer, the etching rate is described in the table, and the TiN layer was evaluated by the following classification.

A: ±10Å or more and less than 50Å

B: ±50Å or more and less than 100Å

C: ±100Å or more and less than 150Å

Further, in Test 803, a TiN substrate having a surface oxygen concentration of TiN of 0.2 mol%, 1.9 mol%, 4.1 mol%, 6.0 mol%, 8.1 mol%, 9.9 mol%, and 12.1 mol% was prepared, and the same was carried out. As a result of the experiment, it was found that the surface oxygen concentration was 6.0 mol%, and the defect performance of the TiN substrate became particularly good.

(Example 5)

In the above test 803, the etching inhibitor was changed in the same manner as in the test 702 to test 729 of Table 7, except that the etching test was performed in the same manner. As a result, the etching rate ratio (TiN/Cu) of TiN and Cu showed a good result of 3 or more, and both the in-plane uniformity and the defect performance of TiN were "A".

The invention will be described based on this embodiment, but we do not limit our invention in any of the details of the description, unless otherwise specified, and should not violate the spirit of the invention as shown in the accompanying patent application. Explain widely with scope.

The present application claims priority to Japanese Patent Application No. 2013-012531, filed on Jan. 25,,,,,,,,,,,,, This manual.

2‧‧‧SiON layer

3‧‧‧SiOC layer

4‧‧‧2nd layer (metal layer)

5‧‧‧through hole

20‧‧‧Substrate

Claims (24)

An etching method for treating a substrate containing a first layer containing titanium nitride (TiN) and a second layer containing a transition metal by using a monolithic apparatus, and having a pH of 1 or more containing a specific fluorine compound and an oxidizing agent The first layer is preferentially removed by contacting the etching solution with the substrate, and the specific fluorine compound is selected from the group consisting of a metal salt of hydrofluoric acid and an ammonium salt of hydrofluoric acid. The etching method according to claim 1, wherein the transition metal is selected from the group consisting of Co, Ni, Cu, Ag, Ta, Hf, W, Pt, and Au. The etching method according to claim 1, wherein the specific fluorine compound is ammonium fluoride or tetramethylammonium fluoride. The etching method according to claim 1, wherein the oxidizing agent is ammonium nitrate, nitric acid, methanesulfonic acid, perchloric acid, ammonium perchlorate or periodic acid. The etching method according to claim 1, wherein the etching rate (R1) of the first layer is 20 Å/min or more and 600 Å/min or less. The etching method according to claim 1, wherein the etching solution further contains at least one type of corrosion inhibitor selected from the group consisting of nitrogen-containing organic compounds and aromatic compounds. The etching method according to any one of claims 1 to 6, wherein the corrosion inhibitor comprises a compound represented by any one of the following formulas (I) to (IX); [Chemical Formula 1] (R ¹ to R ³⁰ each independently represent a hydrogen atom or a substituent; in this case, the adjacent members may be linked or condensed to each other to form a cyclic structure; A represents a hetero atom; wherein, when A is divalent; There is no R ¹ , R ³ , R ⁶ , R ¹¹ , R ²⁴ , R ²⁸ ) which are substituted here. The etching method according to claim 7, wherein the corrosion inhibitor is contained in a range of 0.01% by mass to 10% by mass. The etching method according to claim 1, wherein the one-chip device includes a processing tank, and the semiconductor substrate is transferred or rotated in the processing tank, and the etching liquid is supplied in the processing tank The etching liquid is in contact with the semiconductor substrate. The etching method according to claim 1, wherein the specific fluorine compound is contained in an amount of from 0.001% by mass to 20% by mass. The etching method according to Item 1, wherein the oxidizing agent is contained in an amount of from 0.005% by mass to 30% by mass. An etching method as described in claim 1, wherein the pH exceeds 3 And it is 7 or less. The etching method according to claim 1, wherein the first layer has a thickness of 0.005 μm to 0.3 μm. The etching method according to claim 1, wherein the etching solution is prepared as a kit including a first liquid containing the specific fluorine compound and a second liquid containing the oxidizing agent, and the second liquid and the semiconductor substrate are prepared. Mix and use at the appropriate time before contact. The etching method according to claim 14, wherein the temperature of the two liquids is adjusted to be mixed. The etching method according to the first aspect of the invention, wherein the one-piece device includes a swing type nozzle, and the nozzle is sprayed while being moved in a surface direction with respect to a surface of the semiconductor substrate to supply the etching liquid. An etchant for treating a substrate comprising a first layer containing titanium nitride (TiN) and a second layer containing a transition metal, comprising a metal salt selected from hydrofluoric acid, using a monolithic device And a specific fluorine compound and an oxidizing agent of the ammonium salt. The etching solution according to claim 17, which comprises 0.001% by mass to 20% by mass of the above specific fluorine compound. The etching solution according to claim 17, which comprises 0.005 mass% to 30 mass% of the above oxidizing agent. The etching solution according to claim 17, wherein the pH is -1 to 7. The etching solution according to claim 17, which further comprises a group selected from the group consisting of nitrogen-containing organic compounds, aromatic compounds, and oxygen-containing organic compounds. At least one corrosion inhibitor. The etching solution according to any one of the items (1) to (2), which further contains a compound represented by any one of the following formulas (I) to (IX) as an anticorrosive agent; (R ¹ to R ³⁰ each independently represent a hydrogen atom or a substituent; in this case, the adjacent members may be linked or condensed to each other to form a cyclic structure; A represents a hetero atom; wherein, when A is divalent; There is no R ¹ , R ³ , R ⁶ , R ¹¹ , R ²⁴ , R ²⁸ ) which are substituted here. A method of manufacturing a semiconductor device, which comprises removing a first layer containing titanium nitride by an etching method according to any one of claims 1 to 16, and manufacturing a semiconductor element from a residual substrate . An etching solution set for etching a substrate including a first layer containing titanium nitride (TiN) and a second layer containing a transition metal using a monolithic device The liquid jacket group includes a first liquid containing a specific fluorine compound and a second liquid containing an oxidizing agent, and is mixed and used at an appropriate timing before the two liquids are brought into contact with the semiconductor substrate.