Classifications

• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K13/00—Etching, surface-brightening or pickling compositions
  • C09K13/04—Etching, surface-brightening or pickling compositions containing an inorganic acid
  • C09K13/06—Etching, surface-brightening or pickling compositions containing an inorganic acid with organic material
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
  • H10P50/00—Etching of wafers, substrates or parts of devices
  • H10P50/60—Wet etching
  • H10P50/66—Wet etching of conductive or resistive materials
  • H10P50/663—Wet etching of conductive or resistive materials by chemical means only
  • H10P50/667—Wet etching of conductive or resistive materials by chemical means only by liquid etching only
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/02—Inorganic compounds ; Elemental compounds
  • C11D3/04—Water-soluble compounds
  • C11D3/042—Acids
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/16—Organic compounds
  • C11D3/168—Organometallic compounds or orgometallic complexes
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/39—Organic or inorganic per-compounds
  • C11D3/3942—Inorganic per-compounds
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/395—Bleaching agents
  • C11D3/3956—Liquid compositions
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D7/00—Compositions of detergents based essentially on non-surface-active compounds
  • C11D7/02—Inorganic compounds
  • C11D7/04—Water-soluble compounds
  • C11D7/08—Acids
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D7/00—Compositions of detergents based essentially on non-surface-active compounds
  • C11D7/22—Organic compounds
  • C11D7/26—Organic compounds containing oxygen
  • C11D7/266—Esters or carbonates
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
  • C23F1/00—Etching metallic material by chemical means
  • C23F1/10—Etching compositions
  • C23F1/14—Aqueous compositions
  • C23F1/32—Alkaline compositions
  • C23F1/40—Alkaline compositions for etching other metallic material
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
  • H10P52/00—Grinding, lapping or polishing of wafers, substrates or parts of devices
  • H10P52/40—Chemomechanical polishing [CMP]
  • H10P52/403—Chemomechanical polishing [CMP] of conductive or resistive materials
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
  • H10P70/00—Cleaning of wafers, substrates or parts of devices
  • H10P70/20—Cleaning during device manufacture
  • H10P70/27—Cleaning during device manufacture during, before or after processing of conductive materials, e.g. polysilicon or amorphous silicon layers
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D2111/00—Cleaning compositions characterised by the objects to be cleaned; Cleaning compositions characterised by non-standard cleaning or washing processes
  • C11D2111/10—Objects to be cleaned
  • C11D2111/14—Hard surfaces
  • C11D2111/22—Electronic devices, e.g. PCBs or semiconductors

Definitions

• the present invention relates to a novel treatment liquid for suppressing a ruthenium-containing gas generated when a semiconductor wafer containing ruthenium and a treatment liquid are brought into contact with each other in a semiconductor element manufacturing process.
• the design rules for semiconductor devices have become finer, and wiring resistance tends to increase.
• the increase in wiring resistance it has become remarkable that the high-speed operation of the semiconductor element is hindered, and countermeasures are required. Therefore, as the wiring material, a wiring material having an electromigration resistance and a reduced resistance value is desired as compared with the conventional wiring material.
• ruthenium Compared to conventional wiring materials such as aluminum and copper, ruthenium has high electromigration resistance and can reduce the resistance value of wiring, so it is particularly noteworthy as a wiring material with a semiconductor element design rule of 10 nm or less. Has been done. In addition to wiring materials, ruthenium can prevent electromigration even when copper is used as the wiring material, so it is also being considered to use ruthenium as a barrier metal for copper wiring. ..
• the wiring is formed by dry or wet etching as in the conventional wiring material.
• dry etching with an etching gas, etching by CMP polishing, and removal of ruthenium, more precise etching is desired, and specifically, wet etching is attracting attention.
• RuO 4 - or RuO 4 2- is changed to RuO 4 in the processing solution, part of it is released into the gas phase is gasified. Since RuO 4 is strongly oxidizing, it is not only harmful to the human body, but is also easily reduced to produce RuO 2 particles (RuO 2 particles). In general, RuO 2 particles cause a decrease in yield, which is very problematic in the semiconductor forming process. against this background, possible to suppress the generation of RuO 4 gas is extremely important.
• Patent Document 1 states that the ruthenium film etching solution has a pH of 12 or more and a redox potential of 300 mV vs. Chemical solutions that are SHE or higher are shown. Further, a method of etching a ruthenium film with an oxygenate solution of halogen such as hypochlorite, chlorite, or bromate has been proposed.
• halogen such as hypochlorite, chlorite, or bromate
• Patent Document 2 proposes a method of oxidizing, dissolving and removing ruthenium with an aqueous solution containing orthoperiodic acid having a pH of 11 or higher.
• Patent Document 3 in the chemical mechanical polishing of ruthenium (CMP), CMP slurry comprising RuO 4 gas ruthenium coordinated nitric oxide ligands which do not generate (N-O ligand) is shown.
• CMP ruthenium
• Patent Document 1 For example, the method of etching ruthenium described in Patent Document 1 aims at removing ruthenium residue adhering to the back surface or bevel of a semiconductor substrate, and ruthenium can be dissolved and removed.
• Patent Document 1 does not mention any suppression of RuO 4 gas, and the method described in Patent Document 1 could not actually suppress the generation of RuO 4 gas.
• Patent Document 2 discloses a ruthenium removing composition containing orthoperiodic acid, and shows that an etching residue containing ruthenium can be etched.
• RuO 4 gas it was not possible to suppress the RuO 4 gas generated during the etching process.
• Patent Document 3 by using a CMP slurry comprising ruthenium coordination nitric oxide ligand in CMP (N-O ligand), it is possible to suppress the RuO 4 gas with toxic shows Has been done.
• CMP slurries shown in Patent Document 3 is acidic, the alkaline conditions the dissolution mechanism is different ruthenium, difficult suppression of RuO 4 gas by CMP slurry compositions shown in Patent Document 3.
• RuO 4 gas is generated and there is no effect of suppressing RuO 4 gas. confirmed.
• an object of the present invention is a semiconductor wafer and the processing liquid containing the ruthenium in contacting the alkaline conditions, to provide a RuO 4 gas semiconductor wafer treatment liquid capable of suppressing the occurrence of.
• the present inventors have conducted diligent studies to solve the above problems. Then, it was examined to add various ligands to the processing liquid for semiconductor wafers containing ruthenium. Simply for semiconductor wafer processing solution containing ruthenium, it is impossible to suppress the RuO 4 gas, a combination of various additive components. Consequently, by adding a specific ligand, discovered that it is possible to suppress the RuO 4 gas generation, and have completed the present invention.
• the configuration of the present invention is as follows.
• Item 1 A treatment liquid for a semiconductor of ruthenium, which contains a ligand that coordinates with ruthenium.
• Item 2 The treatment liquid for a semiconductor of ruthenium according to Item 1, wherein the ligand coordinating with ruthenium is a compound having a carbonyl group.
• Item 3 The treatment liquid for a semiconductor of ruthenium according to Item 1, wherein the ligand coordinating with ruthenium is a heterocyclic compound containing nitrogen.
• Item 4 The ruthenium semiconductor according to Item 1 or 2, wherein the ligand coordinating with ruthenium is one or more selected from the group consisting of ligands represented by the following formulas (1) to (4). Treatment liquid.
• R 1 and R 2 are independently hydroxyl groups and / or hydrocarbon groups having 1 to 10 carbon atoms or hydroxyl groups that may contain ether bonds.
• R 3 and R 5 are independently hydrocarbon groups or hydroxyl groups having 1 to 10 carbon atoms which may contain a hydroxyl group or / and an ether bond
• R 4 is a carbon which may contain a hydroxyl group or / and an ether bond. It is a hydrocarbon group of several 1 to 10.
• R 6 , R 8 and R 9 are independently hydrocarbon groups or hydroxyl groups having 1 to 10 carbon atoms which may contain hydroxyl groups and / and ether bonds
• R 7 contains hydroxyl groups and / and ether bonds.
• Item 5 The treatment liquid for a semiconductor of ruthenium according to Item 1 or 2, wherein the ligand coordinating with ruthenium is a ligand represented by the following formula (5).
• R 15 and R 16 are independently hydrocarbon groups or hydroxyl groups having 1 to 10 carbon atoms which may contain hydroxyl groups and / or ether bonds.
• Item 6 The compound having a carbonyl group is oxalic acid, dimethyl oxalate, 1,2,3,4,5,6-cyclohexanehexacarboxylic acid, succinic acid, acetic acid, butane-1,2,3,4-tetra.
• Item 4. The item 4 or 5, wherein the carboxylic acid, dimethylmalonic acid, glutaric acid, diglycolic acid, citric acid, malonic acid, 1,3-adamantandicarboxylic acid, or 2,2-bis (hydroxymethyl) propionic acid. Luthenium treatment liquid for semiconductors.
• Item 7 The treatment liquid for semiconductors of ruthenium according to Item 3, wherein the heterocyclic compound containing nitrogen is a pyridine compound, a piperazine compound, a triazole compound, a pyrazole compound, or an imidazole compound.
• Item 8 The treatment liquid for a semiconductor of ruthenium according to any one of Items 1 to 7, wherein the pH at 25 ° C. is 7 or more and 14 or less.
• Item 9 The treatment liquid for a semiconductor of ruthenium according to any one of Items 1 to 8, wherein the concentration of the ligand coordinating with ruthenium is 0.0001 to 60% by mass.
• Item 11 The treatment liquid for ruthenium for semiconductors according to Item 10, wherein the oxidizing agent is hypochlorite ion and the concentration of the hypochlorite ion is 0.05 to 20.0% by mass.
• Item 12 The treatment liquid for ruthenium for semiconductors according to Item 10, wherein the oxidizing agent is hypobromous acid ion, and the concentration of the hypobromous acid ion is 0.01 to 1.9% by mass.
• Item 13 The treatment liquid for ruthenium for semiconductors according to Item 10, wherein the oxidizing agent is hypobromous acid ion, and the concentration of the hypobromous acid ion is 0.01 to 1.9% by mass.
• the treatment liquid for ruthenium for semiconductors according to Item 10 wherein the oxidizing agent is hypobromous acid ion, and the concentration of the hypobromous acid ion is 0.012 to 1.9% by mass.
• the oxidizing agent is hypochlorite ion and hypobromous acid ion, and the concentration of the hypochlorite ion is 0.05 to 20.0% by mass, and the hypobromous acid ion.
• Item 2 The treatment liquid for semiconductors of ruthenium according to Item 10, which has a concentration of 0.01 to 1.9% by mass.
• Item 15 The treatment liquid for a semiconductor of ruthenium according to Item 10, wherein the oxidizing agent is orthoperiodic acid or metaperiodic acid.
• Item 16 A method for processing a ruthenium-containing wafer using the processing liquid according to any one of Items 1 to 15.
• Item 17 An agent for suppressing the generation of ruthenium-containing gas, which comprises a ligand that coordinates with ruthenium.
• Item 18 The agent for suppressing the generation of ruthenium-containing gas according to Item 17, wherein the ligand coordinating with ruthenium is a compound having a carbonyl group.
• Item 19 The agent for suppressing the generation of ruthenium-containing gas according to Item 17, wherein the ligand coordinating with ruthenium is a heterocyclic compound containing nitrogen.
• Item 20 The ruthenium-containing gas generation inhibitor according to Item 18, wherein the compound having a carbonyl group is at least one selected from the group consisting of compounds represented by the following formulas (1) to (4).
• R 1 and R 2 are independently hydroxyl groups and / or hydrocarbon groups having 1 to 10 carbon atoms or hydroxyl groups that may contain ether bonds.
• R 3 and R 5 are independently hydrocarbon groups or hydroxyl groups having 1 to 10 carbon atoms which may contain a hydroxyl group or / and an ether bond
• R 4 is a carbon which may contain a hydroxyl group or / and an ether bond.
• R 6 , R 8 and R 9 are independently hydrocarbon groups or hydroxyl groups having 1 to 10 carbon atoms which may contain hydroxyl groups and / and ether bonds, and R 7 contains hydroxyl groups and / and ether bonds. It may be a hydrocarbon group having 1 to 10 carbon atoms.
• R 10 , R 12 to 14 are independently hydrocarbon groups having 1 to 10 carbon atoms which may contain a hydroxyl group or / and an ether bond, or a hydroxyl group, and R 11 may contain a hydroxyl group and / and an ether bond.
• Item 21 The ruthenium-containing gas generation inhibitor according to Item 18, wherein the compound having a carbonyl group is a compound represented by the following formula (5).
• R 15 and R 16 are independently hydrocarbon groups or hydroxyl groups having 1 to 10 carbon atoms which may contain hydroxyl groups and / or ether bonds.
• Item 22 The compound having a carbonyl group is oxalic acid, dimethyl oxalate, 1,2,3,4,5,6-cyclohexanehexacarboxylic acid, succinic acid, acetic acid, butane-1,2,3,4-tetra.
• Item 20 or 21 wherein the carboxylic acid, dimethylmalonic acid, glutaric acid, diglycolic acid, citric acid, malonic acid, 1,3-adamantandicarboxylic acid, or 2,2-bis (hydroxymethyl) propionic acid.
• An agent that suppresses the generation of ruthenium-containing gas An agent that suppresses the generation of ruthenium-containing gas.
• Item 23 The agent for suppressing the generation of ruthenium-containing gas according to Item 19, wherein the heterocyclic compound containing nitrogen is a pyridine compound, a piperazine compound, a triazole compound, a pyrazole compound, or an imidazole compound.
• Item 24 The ruthenium-containing gas generation inhibitor according to any one of Items 17 to 23, wherein the pH at 25 ° C.
• Item 25 The agent for suppressing the generation of ruthenium-containing gas according to any one of Items 17 to 24, wherein the concentration of the ligand coordinating with ruthenium is 0.0001 to 60% by mass.
• Item 26 The agent for suppressing the generation of ruthenium-containing gas according to any one of Items 17 to 25, further comprising an oxidizing agent.
• Item 27 The ruthenium-containing gas generation inhibitor according to Item 26, wherein the oxidizing agent is hypochlorite ion and the concentration of the hypochlorite ion is 0.05 to 20.0% by mass.
• Item 28 The ruthenium-containing gas generation inhibitor according to Item 26, wherein the oxidizing agent is hypobromous acid ion and the concentration of the hypobromous acid ion is 0.01 to 1.9% by mass.
• Item 29 The oxidizing agent is hypochlorite ion and hypobromous acid ion, and the concentration of the hypochlorite ion is 0.05 to 20.0% by mass, and the hypobromous acid ion.
• Item 2. The ruthenium-containing gas generation inhibitor according to Item 26, which has a concentration of 0.01 to 1.9% by mass.
• Item 30 The ruthenium-containing gas generation inhibitor according to Item 26, wherein the oxidizing agent is orthoperiodic acid or metaperiodic acid.
• Item 31 Use of the ruthenium-containing gas generation inhibitor according to any one of Items 17 to 30.
• Item 32 A treatment agent for ruthenium-containing waste liquid, which comprises a ligand that coordinates with ruthenium.
• Item 33 The treatment agent for ruthenium-containing waste liquid according to Item 32, wherein the ligand coordinating with ruthenium is a compound having a carbonyl group.
• Item 34 The treatment agent for ruthenium-containing waste liquid according to Item 32, wherein the ligand coordinating with ruthenium is a heterocyclic compound containing nitrogen.
• Item 35 The ruthenium-containing waste liquid treatment agent according to Item 33, wherein the compound having a carbonyl group is at least one selected from the group consisting of compounds represented by the following formulas (1) to (4).
• R 1 and R 2 are independently hydroxyl groups and / or hydrocarbon groups having 1 to 10 carbon atoms or hydroxyl groups that may contain ether bonds.
• R 3 and R 5 are independently hydrocarbon groups or hydroxyl groups having 1 to 10 carbon atoms which may contain a hydroxyl group or / and an ether bond
• R 4 is a carbon which may contain a hydroxyl group or / and an ether bond.
• R 6 , R 8 and R 9 are independently hydrocarbon groups or hydroxyl groups having 1 to 10 carbon atoms which may contain hydroxyl groups and / and ether bonds, and R 7 contains hydroxyl groups and / and ether bonds. It may be a hydrocarbon group having 1 to 10 carbon atoms.
• R 10 , R 12 to 14 are independently hydrocarbon groups having 1 to 10 carbon atoms which may contain a hydroxyl group or / and an ether bond, or a hydroxyl group, and R 11 may contain a hydroxyl group and / and an ether bond.
• Item 36 The ruthenium-containing waste liquid treatment agent according to Item 33, wherein the compound having a carbonyl group is a compound represented by the following formula (5). (R 15 and R 16 are independently hydrocarbon groups or hydroxyl groups having 1 to 10 carbon atoms which may contain hydroxyl groups and / or ether bonds.)
• Item 37 The treatment agent for ruthenium-containing waste liquid according to any one of Items 32 to 36, wherein the concentration of the ligand coordinating with ruthenium is 0.0001 to 60% by mass.
• Item 38 A method for treating a ruthenium-containing waste liquid using the treatment agent according to any one of Items 32 to 37.
• the generation of RuO 2 particles and ruthenium-containing gas, which causes a decrease in yield, can be suppressed in the semiconductor manufacturing process by the effect of the ligand coordinating with ruthenium.
• a ligand is added to trap a ruthenium-containing compound (RuO 4, etc.) produced by dissolution of ruthenium, and a compound containing heteroatoms such as nitrogen, oxygen, sulfur, phosphorus, and more specifically, for example. , Amino group, phosphino group, carboxyl group, carbonyl group, thiol group, and heterocyclic compound containing nitrogen.
• ruthenium-containing compound RuO 4, etc.
• heteroatoms such as nitrogen, oxygen, sulfur, phosphorus, and more specifically, for example.
• Amino group, phosphino group, carboxyl group, carbonyl group, thiol group, and heterocyclic compound containing nitrogen are ruthenium treatment solutions for semiconductors and ruthenium-containing gas generation inhibitors.
• ruthenium semiconductor means a semiconductor containing ruthenium.
• various types are known as ligands that coordinate with ruthenium (Ru), but the term "ligand that coordinates with ruthenium” as used herein refers to a ruthenium-containing compound (as will be described later). Refers to those coordinated to RuO 4 etc.). That is, a compound that does not coordinate with a ruthenium-containing compound is not included in the "ligand that coordinates with ruthenium” of the present invention.
• the ligand forming a ruthenium (Ru) and complexes, for example, chloride ion (Cl -) and nitrate ion (NO 3 -) and the like are known.
• these ligands although coordinated to ruthenium (Ru), since the ruthenium-containing compound (RuO 4, etc.) does not coordinate, the "ruthenium coordinated ligand" of the present invention Not included.
• strong bonds between RuO, RuO 4 oxygen (O) and the ligand (Cl -, NO 3 -) for slow substitution reactions, or, between RuO It is presumed that this is because the bond between the two is strong and an appropriate spatial arrangement cannot be obtained (coordination is not possible due to three-dimensional restrictions). Therefore, it is important to select an appropriate ligand as the ligand that coordinates with ruthenium, that is, the ligand that coordinates with the ruthenium-containing compound (RuO 4, etc.).
• Ligands coordinating with the ruthenium present invention a mechanism of suppressing the RuO 4 gas generation is estimated as follows. That is, when the ruthenium alkaline solution is dissolved, ruthenium RuO 4 - or RuO 4 2-ionic or RuO 4 or neutral molecules, such as RuO 2 (ruthenium-containing compounds such as; these species ( Ions or neutral molecules) are sometimes referred to as RuO 4 etc.). RuO 4 - or RuO 4 2-, RuO 2 changes to RuO 4 in solution, some or all are released into the gas phase as a RuO 4 gas.
• RuO 4 - or RuO 4 2- RuO 2 changes to RuO 4 in solution, some or all are released into the gas phase as a RuO 4 gas.
• RuO 4 dissolved in the solution as an example.
• RuO 4 ruthenium exists in a positively biased state due to the difference in electronegativity between ruthenium and oxygen.
• lone electron pairs of N, P, O or S in the amino group, phosphino group, carboxyl group, carbonyl group and thiol group contained in the ligand coordinating with ruthenium of the present invention are arranged. It is considered to be ranked.
• the ligand is a nitrogen-containing heterocyclic compound, it is considered that the lone electron pair of N in the nitrogen-containing heterocyclic compound coordinates to the positively charged ruthenium.
• a heteroatom other than N is contained in the nitrogen-containing heterocyclic compound, it is also conceivable that a lone electron pair of P, O or S is coordinated to positively charged ruthenium.
• RuO 4 is generally known as a metal oxide having strong electrophilicity because the electronegativity of ruthenium constituting it is high among metals. Since a metal oxide having a strong electrophile is easily coordinated to an unsaturated bond carbon, it is considered that RuO 4 coordinates to a compound containing a carbonyl group having an unsaturated bond. When the ligand is a heterocyclic compound containing nitrogen, RuO 4 is considered coordinated to heterocycle or heteroatom of a heterocyclic compound containing nitrogen.
• the ligand may be coordinated to RuO 4 or the like, or the ligand may be reversely coordinated to RuO 4 or the like.
• ruthenium and coordination are included in both cases.
• the ruthenium-dissolved solution include a ruthenium-containing treatment liquid for semiconductors of the present invention in which ruthenium is dissolved, a ruthenium-containing gas generation inhibitor, and a ruthenium-containing waste liquid treatment agent.
• ruthenium semiconductor treatment liquid, ruthenium-containing gas generation inhibitor, and ruthenium-containing waste liquid treatment agent may be collectively referred to as treatment liquid and the like.
• ligand in order to suppress the generation of RuO 4 gas, ligand needs to include a lone pair of electrons, but if a ligand containing inter alia carbonyl group or carboxyl group, or a nitrogen
• the compound containing a carbonyl group one or more selected from the group consisting of ketones, carboxylic acids, esters, amides, enones, acid chlorides, acid anhydrides and the like, which are highly stable to oxidizing agents, are preferable.
• the compound is preferably one or more selected from the group consisting of the compounds represented by the formulas (1) to (5).
• R 1 and R 2 are independently hydroxyl groups and / or hydrocarbon groups having 1 to 10 carbon atoms or hydroxyl groups that may contain ether bonds.
• R 3 and R 5 are independently hydrocarbon groups or hydroxyl groups having 1 to 10 carbon atoms which may contain a hydroxyl group or / and an ether bond, and R 4 is a carbon which may contain a hydroxyl group or / and an ether bond. It is a hydrocarbon group of several 1 to 10.
• R 6 , R 8 and R 9 are independently hydrocarbon groups or hydroxyl groups having 1 to 10 carbon atoms which may contain hydroxyl groups and / and ether bonds, and R 7 contains hydroxyl groups and / and ether bonds. It may be a hydrocarbon group having 1 to 10 carbon atoms.
• R 10 , R 12 to 14 are independently hydrocarbon groups having 1 to 10 carbon atoms which may contain a hydroxyl group or / and an ether bond, or a hydroxyl group, and R 11 may contain a hydroxyl group and / and an ether bond. It is a good hydrocarbon group with 1 to 10 carbon atoms.
• Rs 15 and 16 are independently hydroxyl groups and / or hydrocarbon groups having 1 to 10 carbon atoms or hydroxyl groups that may contain ether bonds.
• the ligand having the above structure can stably exist in an alkaline treatment liquid or the like. Further, in the above formulas (1) to (5), by appropriately selecting the number of carbon atoms of R1 to 16 and the presence or absence of a hydroxyl group or / and an ether bond, the solubility of the ligand in a treatment liquid or the like and the said it is possible to control the stability of the compounds consisting of ligand and RuO 4 and the like.
• the carbon number of R 1 to 16 is preferably 10 or less, and more preferably 5 or less.
• R 1 to 16 in the above formulas (1) to (5) are hydroxyl groups or /. And preferably contains an ether bond.
• the ligand that can be preferably used is Preferably, amines such as triethanolamine, nitrilotriacetic acid, ethylenediaminetetraacetic acid and glycine, thiols such as cysteine and methionine, phosphines such as tributylphosphine and tetramethylenebis (diphenylphosphine), acetic acid, formic acid, lactic acid, Glycolic acid, 2,2-bis (hydroxymethyl) propionic acid, gluconic acid, ⁇ -glucoheptoic acid, heptinic acid, phenylacetic acid, phenylglycolic acid, benzylic acid, gallic acid, caric acid, naphthoic acid, anis Monocarboxylic acids such as acids, salicylic acid, cresotinic acid, acrylic acid, benzoic acid or their esters, malic acid, adipic acid, succinic acid, maleic
• acetic acid formic acid, lactic acid, glycolic acid, 2,2-bis (hydroxymethyl) propionic acid, gluconic acid, ⁇ -glucoheptoic acid, heptinic acid, phenylacetic acid, phenylglycolic acid, benzylic acid, galvanic acid.
• Monocarboxylic acids such as acids, cinnamic acid, naphthoic acid, anis acid, salicylic acid, cresotic acid, acrylic acid, benzoic acid or their esters, malic acid, adipic acid, succinic acid, maleic acid, tartrate acid, oxalic acid, shu Dicarboxylic acids such as dimethyl acid, glutaric acid, malonic acid, 1,3-adamantan dicarboxylic acid, diglycolic acid or their esters, tricarboxylic acids typified by citric acid or their esters, butane-1,2,3 Tetracarboxylic acid represented by 4-tetracarboxylic acid or its esters, hexacarboxylic acid represented by 1,2,3,4,5,6-cyclohexanehexacarboxylic acid or its esters, ethyl acetoacetate, dimethyl Carbonyl compounds such as malonic acid, More preferably, oxalic acid, dimethyl oxa
• the ligand that can be used in the present invention may be any ligand that can form a ruthenium coordinate, and is not limited to that if an isomer is present.
• lactic acid has a D-form and an L-form, but the ligand is not limited by such a difference in isomers.
• RuO 4 or the like or the reverse coordination from RuO 4 or the like it may be a monodentate coordination or a multidentate coordination such as chelate. In these cases, RuO 4, etc. per molecule, to the ligand molecule may be coordinated, multiple molecules may be coordinated.
• the nitrogen-containing heterocyclic compound refers to a compound having a heterocycle containing one or more nitrogen.
• the nitrogen-containing heterocyclic compound that can be used as the ligand of the present invention preferably, a piperidine compound, a pyridine compound, a piperazine compound, a pyridazine compound, a pyrimidine compound, a pyrazine compound, a 1,2,4-triazine compound, 1 , 3,5-triazine compound, oxazine compound, thiazine compound, citocin compound, timine compound, uracil compound, pyrrolidine compound, pyrrolin compound, pyrrol compound, pyrazolidine compound, imidazolidine compound, imidazoline compound, pyrazole compound, imidazole compound, triazole compound , Tetrazole compound, oxazole compound, thiazole compound, oxaziazole compound, thiazazole compound, thiazol
• a triazole compound such as a pyridine compound, a piperazine compound, and a benzotriazole, a pyrazole compound, and an imidazole compound
• a triazole compound such as a pyridine compound, a piperazine compound, and a benzotriazole, a pyrazole compound, and an imidazole compound
• the present invention is not limited thereto.
• the heterocyclic compound containing nitrogen when an isomer is present, it can be used as the ligand of the present invention without distinction.
• the heterocyclic compound containing nitrogen when the heterocyclic compound containing nitrogen is an indole compound, it may be 1H-indole, 2H-indole, 3H-indole, or a mixture thereof. There may be.
• heterocyclic compound containing nitrogen may be modified with an arbitrary functional group, or may have a structure in which a plurality of rings are condensed.
• the heterocyclic compound containing nitrogen may be used alone or in combination of two or more.
• a heterocyclic compound containing nitrogen and a ligand coordinating with ruthenium other than the heterocyclic compound containing nitrogen can also be used in combination.
• the ligand coordinating with ruthenium of the present invention is a nitrogen-containing heterocyclic compound
• the lone electron pair of N in the nitrogen-containing heterocyclic compound is assigned to the positively charged ruthenium by the above mechanism.
• gasification of RuO 4 or the like is suppressed and the amount of RuO 4 gas generated is reduced. Conceivable. Further, since the generation of RuO 4 is hindered, it is presumed that the generation of RuO 2 particles generated by the reduction of RuO 4 is also suppressed.
• Ligands of the present invention the liquid for processing the processing liquid and ruthenium to be described later (hereinafter, collectively described as a semiconductor treatment liquid ruthenium)
• the effect of expression when included in, the RuO 4 gas Not only suppression, but also improvement of stability of ruthenium in the treatment liquid for semiconductors can be mentioned.
• the ligand of the present invention has the ability to coordinate to metals other than ruthenium. That is, by coordinating with a metal contained in a trace amount of ruthenium as an impurity in the processing liquid for semiconductors of ruthenium, it is possible to suppress a decrease in stability of the treatment liquid due to metal impurities.
• the ligand of the present invention is also effective in improving the stability of the oxidizing agent. That is, when the ligand of the present invention coordinates with a metal impurity in the treatment liquid, the reaction activity between the metal and the oxidant is reduced and the decomposition of the oxidant is suppressed. Improves stability.
• the treatment liquid Semiconductor processing liquid for the ruthenium present invention (hereinafter, simply described as the treatment liquid) is a treatment liquid capable of processing a semiconductor wafer containing ruthenium while suppressing the occurrence of the ruthenium-containing gas such as RuO 4 gas. Therefore, the treatment liquid of the present invention is a treatment liquid that can be suitably used in an etching step, a residue removing step, a cleaning step, a CMP step, a ruthenium-containing waste liquid treatment step, and the like in a semiconductor manufacturing process.
• the ruthenium contained in the semiconductor wafer to which the treatment liquid of the present invention is applied may be formed by any method.
• ruthenium methods widely known in the semiconductor manufacturing process, such as CVD, ALD, sputtering, and plating, can be used.
• These rutheniums may be metallic rutheniums, ruthenium oxides, alloys with other metals, intermetallic compounds, ionic compounds, and complexes.
• ruthenium may be exposed on the surface of the wafer, or may be covered with another metal, a metal oxide film, an insulating film, a resist, or the like.
• the treatment liquid of the present invention when not actively dissolve the ruthenium, i.e., be processing ruthenium is the protection of the object, ruthenium containing gas, such as RuO 4 gas generated from ruthenium and very slightly soluble It is possible to suppress.
• the concentration of the ligand in the treatment liquid is preferably 0.0001 to 60% by mass. If the amount of the ligand added is too small , not only the interaction with RuO 4 and the like is weakened and the effect of suppressing the RuO 4 gas is reduced, but also the amount of RuO 4 and the like that can be dissolved in the treatment liquid is reduced. The number of times the liquid is reused is reduced. On the other hand, if the amount added is too large, the amount of the ligand adsorbed on the ruthenium surface increases, which causes a decrease in the ruthenium dissolution rate and uneven etching of the ruthenium surface.
• the treatment liquid of the present invention preferably contains 0.0001 to 60% by mass of the ligand, more preferably 0.01 to 35% by mass, and even more preferably 0.1 to 20% by mass. ..
• adding a ligand only one type may be added, or two or more types may be added in combination. Even if it contains 2 or more ligands, if a concentration range sum of the concentration of ligand, it is possible to effectively suppress the occurrence of RuO 4 gas.
• the treatment liquid of the present invention when used in the ruthenium wiring forming step, it is as follows. First, a substrate made of a semiconductor (for example, Si) is prepared. The prepared substrate is subjected to an oxidation treatment to form a silicon oxide film on the substrate. After that, an interlayer insulating film made of a low dielectric constant (Low-k) film is formed, and via holes are formed at predetermined intervals. After the via hole is formed, ruthenium is embedded in the via hole by thermal CVD, and a ruthenium film is further formed. By etching with the treatment solution of the present invention the ruthenium film is flattened while suppressing RuO 4 gas generation. As a result, it is possible to form a highly reliable ruthenium wiring in which RuO 2 particles are suppressed.
• a substrate made of a semiconductor for example, Si
• the method for treating a semiconductor wafer with the treatment liquid of the present invention is not limited to wet etching, and can be suitably used as a treatment liquid for cleaning and residue removal.
• the wafer when used for cleaning, the wafer is wet-etched with a treatment liquid containing an oxidizing agent or the like, and then the wafer is subjected to a treatment liquid containing a ligand coordinating with ruthenium of the present invention. Can be washed.
• the ruthenium-containing compound generated by wet etching can be used as a ruthenium coordinated body to suppress the generation of RuO 4 gas and prevent the generation of RuO 2 particles. It will be possible.
• the treatment of the wafer containing ruthenium with the treatment liquid of the present invention may be a single-wafer treatment or a dipping treatment.
• Treatment solution of the present invention may be contained in the etching solution of the ruthenium may be added to the ruthenium-containing solutions in order to suppress the RuO 4 gas for the purpose of waste treatment.
• the temperature of the treatment liquid is not particularly limited, in any of the processing temperatures, RuO 4 gas suppressing effect exerted by the ligand contained in the processing solution.
• the residue other than the ligand and the organic solvent and other additives described in detail below is water.
• the water contained in the treatment liquid of the present invention is preferably water from which metal ions, organic impurities, RuO 2 particles, etc. have been removed by distillation, ion exchange treatment, filter treatment, various adsorption treatments, etc., particularly pure water or ultrapure water. Pure water is preferable. Such water can be obtained by a known method widely used in semiconductor manufacturing.
• the treatment liquid of the present invention may contain an oxidizing agent.
• Oxidant refers to one having the ability to substantially dissolve ruthenium contained in a semiconductor wafer.
• oxidizing agent a known oxidizing agent as an oxidizing agent capable of dissolving ruthenium can be used without any limitation.
• the oxidizing agent include, but are not limited to, halogen oxygen acid, permanganate, and salts thereof, hydrogen peroxide, ozone, cerium (IV) salt and the like.
• the halogen oxygen acid is hypochlorous acid, chlorous acid, chloric acid, perbromic acid, hypobromous acid, hypobromous acid, bromic acid, periodic acid, hypoiodous acid, periodic acid, and iodine.
• acid metaperiodic acid, orthoperiodic acid or ions thereof.
• Semiconductor wafer treatment liquid containing oxidizing agent it is possible to dissolve the ruthenium contained in the wafer, the treatment liquid containing a ligand coordinating with the oxidant and ruthenium, dissolution of ruthenium RuO 4 gas Suppression can be performed at the same time.
• the treatment liquid contains an oxidizing agent
• the dissolution of ruthenium is promoted and the redissolution of the precipitated RuO 2 particles is promoted. Therefore, the treatment liquid containing the ligand and the oxidizing agent can efficiently treat the ruthenium-containing wafer while suppressing the generation of RuO 4 gas and RuO 2 particles.
• oxidizing agents periodic acid, ions of halogen oxygen acid, or hydrogen peroxide are suitable as the oxidizing agent because they are alkaline, can be used stably, and the concentration range can be widely selected.
• Hypobromous acid, metaperiodic acid, orthoperiodic acid, or their ions are more preferred, with hypochlorous acid, hypobromous acid, hypobromous acid ion, or hypobromous acid ion being the most preferred.
• these oxidizing agents may be present as salts in the treatment liquid, and as the salts, for example, tetraalkylammonium hypochlorite or tetraalkylammonium hypobromite is suitable.
• the alkyl chain of the tetraalkylammonium ion contained in these salts preferably has 1 to 5 carbon atoms, and tetramethylammonium hypochlorous acid having 1 carbon atom or tetramethylammonium hypobromous acid is more preferable. ..
• the oxidizing agent contained in the treatment liquid may be one kind or two or more kinds.
• the method for producing the above-mentioned tetramethylammonium hypochlorite or tetramethylammonium hypobromite is not particularly limited, and those produced by a widely known method can be used. For example, a method of blowing chlorine or bromine into tetramethylammonium hydroxide, a method of mixing hypochlorous acid or hypobromous acid with tetramethylammonium hydroxide, hypochlorite or hypobromous acid using an ion exchange resin.
• Tetramethylammonium chlorite or tetramethylammonium hypobromite can be preferably used.
• the concentration range of hypochlorite ions may be 0.05 to 20.0% by mass with respect to the entire treatment liquid. preferable. If it is within the above range, the decomposition reaction of hypochlorite ions in the treatment liquid is suppressed, the decrease in the concentration of the hypochlorite ions is suppressed, and ruthenium is etched at an etching rate of 20 ⁇ / min or more. Is possible. Therefore, the range of the concentration of hypochlorite ion is preferably 0.1 to 15% by mass, more preferably 0.3 to 10% by mass, and further preferably 0.5 to 6% by mass.
• the treatment liquid of the present invention is a treatment liquid containing hypochlorite ions
• the hypochlorite ions may exist as hypochlorous acid, which is a conjugate acid, depending on the pH of the treatment liquid.
• the total concentration of hypochlorite ion and hypochlorous acid contained in the treatment liquid may be within the above concentration range.
• the concentration of the hypobromous acid ions is not particularly limited as long as it does not deviate from the object of the present invention, but is preferably 0. It is 0.01% by mass or more and 1.9% by mass or less. If it is less than 0.01% by mass, the rate of etching ruthenium is low and the practicality is low. On the other hand, if it exceeds 1.9% by mass, decomposition of hypobromous acid ions is likely to occur, so that the etching rate of ruthenium becomes difficult to stabilize.
• hypobromous acid ion In order to stably etch ruthenium at a sufficient rate, it is more preferably 0.012% by mass or more and 1.9% by mass or less, and the concentration of the hypobromous acid ion is 0.048% by mass or more. It is more preferably 1.9% by mass or less, and most preferably 0.096% by mass or more and 1.0% by mass or less.
• hypobromous acid ion When the treatment liquid of the present invention is a treatment liquid containing hypobromous acid ion, hypobromous acid ion may exist as hypobromous acid which is a conjugate acid depending on the pH of the treatment liquid. In such a case, the total concentration of hypobromous acid ion and hypobromous acid contained in the treatment liquid may be within the above concentration range.
• the treatment liquid of the present invention and the ruthenium-containing gas generation inhibitor described later contain hypobromous acid ions, it is preferable to further contain an oxidizing agent (second oxidizing agent) other than hypobromous acid ions.
• an oxidizing agent second oxidizing agent
• the second oxidizing agent is contained in the treatment liquid of the present invention and the agent for suppressing the generation of ruthenium-containing gas, the bromide ion (Br ⁇ ) generated by the decomposition of hypobromous acid ion is converted into hypobromous acid ion again. It plays a role in oxidizing.
• the treatment liquid of the present invention and the agent for suppressing the generation of ruthenium-containing gas may further contain an oxidizing agent different from these oxidizing agents in addition to hypobromous acid ion and the second oxidizing agent, but hypobromous acid by include acid ion and a second oxidizing agent, as described below, and improve the stability of the etching rate can be expected generation of suppression of additional RuO 4 gas.
• hypobromous acid ion When oxidizing the ruthenium, hypobromite ions Br - it is reduced to.
• hypobromous acid ion is easily spontaneously decomposed in the treatment liquid, and a part of it changes to Br ⁇ .
• the decomposition of hypobromous acid ion is promoted by ultraviolet rays and visible light, and a part of the hypobromous acid ion is changed to Br ⁇ .
• hypobromous acid ion is decomposed by heating, contact with acid, and contact with metal, and a part of hypobromous acid ion is changed to Br ⁇ .
• the second oxidant suitable and hypobromite ions that included the generation inhibitor of the processing solution and a ruthenium-containing gas
• stabilization time of the etching rate increases, and the generation amount of RuO 4 gas descend.
• the generation amount of RuO 4 gas is lowered, as described later, by keeping the redox potential of the solution, because the ligands are easily coordinated to the ruthenium-containing compound.
• the second oxidant which may be contained in the treatment liquid and the generation inhibitor of the ruthenium-containing gas, has a redox potential between the second oxidant / the chemical species generated by the reduction of the second oxidant.
• hypobromite ion / Br - is preferably greater than the redox potential of the system.
• Br - can the be oxidized to hypobromite ion.
• the oxidation-reduction potential between the second oxidant that may be contained in the treatment liquid and the generation inhibitor of the ruthenium-containing gas / the chemical species generated by the reduction of the second oxidant is the second oxidant and the second oxidant.
• the redox potential between the second oxidant / the chemical species generated by the reduction of the second oxidant is RuO 4 - or RuO 4 - RuO 4 dissolved in If / RuO 4 system higher than the oxidation-reduction potential (1.0 V vs. SHE) of the processing liquid and generating inhibitors of the ruthenium-containing gas
• 2- etc. Will be oxidized to RuO 4 by the oxidizing agent, and the generation of RuO 4 gas will increase.
• the second oxidizing agent which may be contained in the treatment liquid of the present invention and the generation inhibitor of the ruthenium-containing gas does not contain a metal element which is a problem in semiconductor production, has high solubility in a solution, and is contained in the solution. It is preferably hypochlorite ion because it exists stably in the water and the concentration can be easily adjusted.
• the concentration of the hypochlorite ions is not limited as long as the gist of the present invention is not deviated. However, it is preferably 0.05% by mass or more and 20% by mass or less. Hypochlorite ions at a concentration of 0.05 wt% smaller than Br - can not be efficiently oxidized, oxidation-reduction potential of the ruthenium etch rate and solution is lowered. On the other hand, if the amount of hypochlorite ion added is larger than 20% by mass, the stability of hypochlorite ion is lowered, which is not appropriate.
• concentration of hypochlorite ions is 4 mass% or less than 0.5 wt% Is most preferable.
• concentration range of hypobromous acid ion in the system in which hypobromous acid ion and hypochlorite ion coexist is the same as the above-described range.
• hypobromous acid ion or hypochlorite ion may exist as a conjugate acid, hypobromous acid or hypochlorous acid, respectively.
• the total concentration of hypobromous acid ion and hypobromous acid contained in the treatment liquid and the total concentration of hypochlorite ion and hypochlorous acid may be within the above concentration ranges, respectively. ..
• Non-Patent Document 1 an organic solvent having a relative permittivity lower than that of water 78 (Non-Patent Document 1) is used as the organic solvent added to the treatment liquid of the present invention. It is desirable to add.
• any organic solvent may be used as long as it is an organic solvent lower than water, but a solvent having a relative permittivity at 25 ° C. of 45 or less is preferable.
• organic solvents 1,4-dioxane (relative permittivity 2.2), carbon tetrachloride (relative permittivity 2.2), benzene (relative permittivity 2.3), and toluene (relative permittivity 2.3).
• Relative permittivity 2.4 propionic acid (relative permittivity 3.4), trichloroethylene (relative permittivity 3.4), diethyl ether (relative permittivity 4.3), chloroform (relative permittivity 4.9), Acetivity (relative permittivity 6.2), methyl benzoate (relative permittivity 6.6), methyl formate (relative permittivity 8.5), phenol (relative permittivity 9.8), p-cresol (relative permittivity 9.8) 9.9), isobutyl alcohol (relative permittivity 17.9), acetone (relative permittivity 20.7), nitroethane (relative permittivity 28.1), acetonitrile (relative permittivity 37), ethylene glycol (relative permittivity 37) 37.7), sulfolan (relative permittivity 43), etc., but of course, the organic solvent is not limited to these.
• an oxidizing agent When an oxidizing agent is contained in the treatment liquid, it is preferable that the two do not react with each other in order to prevent the organic solvent from being decomposed by the oxidizing agent.
• a solvent may be used.
• the oxidizing agent is halogen oxygen acid or halogen oxygen acid ion
• sulfolanes, alkylnitriles, halogenated alkanes, ethers and the like have low reactivity with the above oxidizing agent and are therefore treated.
• It can be suitably used as an organic solvent to be added to the liquid.
• Specific examples of such an organic solvent include sulfolane, acetonitrile, carbon tetrachloride, 1,4-dioxane and the like, but of course, the organic solvent is not limited to these.
• the amount of the organic solvent may be added in an amount necessary to suppress the formation of a precipitate. Therefore, the concentration of the organic solvent in the treatment liquid may be at least 0.1 wt%, but increasing the amount of dissolved ruthenium coordination body is kept in stable in solution RuO 4 and the like as ruthenium coordination body Therefore, the concentration of the organic solvent is preferably 1% by mass or more. Further, as long as the solubility of ruthenium and the storage stability of the treatment liquid are not impaired, the amount of the ruthenium coordinator that can be dissolved in the treatment liquid increases as the amount of the organic solvent added increases, so that a precipitate is formed.
• the organic solvent to be added may be one kind or a plurality of organic solvents may be added in combination. Even when adding a combination of a plurality of organic solvents, if the total concentration of added organic solvent is within the above range, it is possible to suppress the generation of RuO 4 gas.
• the organic solvent in the treatment liquid evaporates during the processing of the semiconductor wafer, so that the concentration of the organic solvent changes and the relative permittivity of the treatment liquid changes. Stable processing becomes difficult.
• the organic solvent preferably has low volatility. Specifically, an organic solvent having a vapor pressure of 50 mmHg or less at 20 ° C. is preferable, and an organic solvent having a vapor pressure of 20 mmHg or less is more preferable.
• the treatment liquid of the present invention preferably has a pH at 25 ° C. of 7 or more and 14 or less.
• pH of the treatment liquid is less than 7, Ru ⁇ 2 particles are likely to be generated, and there arises a problem that the amount of Ru ⁇ 4 gas generated increases.
• the oxidizing agent contained in the treatment liquid is halogen oxygen acid or halogen oxygen acid ion, the decomposition of the oxidizing agent proceeds when the pH is less than 7.
• the pH exceeds 14 it becomes difficult to etch ruthenium, so that it is not suitable as a treatment liquid. Therefore, to the treatment liquid of the present invention is sufficiently exhibited RuO 4 gas generation suppressing ability, pH of the treatment solution is preferably 7 to 14, 7 more preferably super 14 or less, 9 to 13 Is even more preferable.
• the treatment liquid of the present invention may contain other additives conventionally used in the treatment liquid for semiconductors, as long as the object of the present invention is not impaired.
• additives an acid, a metal corrosion inhibitor, a water-soluble organic solvent, a fluorine compound, a reducing agent, a complexing agent, a chelating agent, a surfactant, a defoaming agent, a pH adjuster, a stabilizer, etc. are added. be able to.
• additives may be added alone or in combination of two or more.
• the treatment liquid of the present invention may contain alkali metal ions, alkaline earth metal ions, etc. due to the origin of these additives and the convenience of manufacturing the treatment liquid.
• alkali metal ions, alkaline earth metal ions, etc. may be contained.
• sodium ion, potassium ion, calcium ion and the like may be contained.
• these alkali metal ions, alkaline earth metal ions, etc. remain on the semiconductor wafer, they adversely affect the semiconductor element (adverse effects such as a decrease in the yield of the semiconductor wafer), so the amount thereof is preferably small. , Actually, it is better not to be included infinitely.
• the total amount of the alkali metal ion and the alkaline earth metal ion is preferably 1% by mass or less, more preferably 0.7% by mass or less, and 0.3% by mass or less. It is more preferably 10 ppm or less, and most preferably 500 ppb or less. Therefore, for example, the pH adjuster is not an inorganic alkali represented by an alkali metal hydroxide such as sodium hydroxide or an alkaline earth metal hydroxide such as calcium hydroxide, but ammonia, amine, choline or tetraalkylammonium hydroxide. It is preferable that it is an organic alkali such as.
• the ruthenium-containing gas generation inhibitor is a liquid that suppresses the generation of ruthenium-containing gas by adding it to a liquid for treating ruthenium, and refers to a liquid containing a ligand that coordinates with ruthenium.
• the liquid for treating ruthenium may be any liquid as long as it contains a component that comes into contact with ruthenium and gives a physical or chemical change to the ruthenium, and examples thereof include a solution containing an oxidizing agent. ..
• the oxidizing agent include an oxidizing agent as exemplified in the description of the treatment liquid of the present invention.
• Ruthenium treated with a liquid for treating ruthenium causes all or part of it to dissolve, disperse, or precipitate in the treatment liquid, producing RuO 4 gas and / or RuO 2 particles.
• a liquid containing a liquid for treating ruthenium and a ruthenium-containing gas generation inhibitor of the present invention also referred to as a treatment liquid containing a gas generation inhibitor
• RuO 4 and the like present in the treatment liquid and RuO 4 and the like are present.
• the ligand forms a ruthenium coordinator that dissolves in the treatment solution.
• the RuO 4 and RuO 2 particles dissolved in the process liquid from RuO 4, etc. are formed is suppressed. This is to significantly reduce the RuO 4 gas generated from the RuO 4 dissolved in the treatment liquid and to suppress the generation of RuO 2 particles generated by the RuO 4 gas.
• semiconductor treatment solution of the ruthenium of the present invention contains a ruthenium ligand coordinating, without causing RuO 4 gas is the process liquid capable of processing a semiconductor wafer containing ruthenium .
• the treatment liquid is not only a liquid for treating ruthenium but also a ruthenium-containing gas generation inhibitor. Therefore, the treatment liquid of the present invention can also be used as an agent for suppressing the generation of ruthenium-containing gas.
• the ruthenium-containing gas generation inhibitor preferably contains an oxidizing agent.
• an oxidizing agent By containing an oxidizing agent, the ruthenium in the solution, since the ligand is easily maintained in the coordination form easy, the effect of suppressing RuO 4 gas is increased.
• the inhibitor containing an oxidizing agent is added to the liquid for treating ruthenium so that the dissolved ruthenium is easily changed into RuO 2 particles.
• the dissolved ruthenium for example, RuO 4 - and the like RuO 4
• more likely ligand is maintained in the coordination easy ruthenium species. This is because the redox potential of the solution is kept high by the oxidizing agent.
• oxidizing agent halogen oxygen acid, permanganate, and salts thereof, hydrogen peroxide, ozone, cerium (IV) salt and the like are preferable.
• periodic acid or periodic acid ions are suitable as the oxidizing agent because they are alkaline, can be used stably, and the concentration range can be widely selected, and hypobromous acid, hypobromous acid, and meta.
• Periodic acid, orthoperiodic acid, or ions thereof are more preferred, with hypobromous acid, hypobromous acid, hypobromous acid ion, or hypobromous acid ion being the most preferred.
• these oxidizing agents may be present as salts in the treatment liquid, and as the salts, for example, tetraalkylammonium hypochlorite or tetraalkylammonium hypobromite is suitable.
• the alkyl chain of the tetraalkylammonium ion contained in these salts preferably has 1 to 5 carbon atoms, and more preferably tetramethylammonium hypochlorous acid having 1 carbon atom or tetramethylammonium hypobromous acid.
• the oxidizing agent contained in the ruthenium-containing gas generation inhibitor may be one type or two or more types.
• the concentration range of hypochlorite ions is preferably 0.05 to 20.0% by mass. If it is within the above range, the decomposition reaction of hypochlorite ion in the mixed solution is suppressed, the decrease in the concentration of the hypochlorite ion is suppressed, and the ltenium species in which the ligand is easily coordinated is maintained. It is possible. Therefore, the range of the concentration of hypochlorite ion is preferably 0.1 to 15% by mass, more preferably 0.3 to 10% by mass, and further preferably 0.5 to 6% by mass. , Particularly preferably 0.5 to 4% by mass.
• the concentration of the hypobromous acid ion is 0.01 mass for the same reason as the above-mentioned hypobromous acid ion. It is preferably% or more and 1.9% by mass or less.
• the concentration of the hypobromous acid ion is more preferably 0.012% by mass or more and 1.9% by mass or less, further preferably 0.048% by mass or more and 1.9% by mass or less, and 0.096% by mass. Most preferably, it is by mass% or more and 1.0% by mass or less.
• the ruthenium-containing gas generation inhibitor of the present invention may contain both hypochlorite ion and hypobromous acid ion.
• the concentration of the hypochlorite ion is the same as in the case of the above-mentioned treatment solution.
• the range of is 0.05 to 20.0% by mass.
• the range of the concentration of the hypobromous acid ion is preferably 0.01 to 1.9% by mass, preferably 0.012 to 1.9% by mass, for the same reason as in the case of the above-mentioned treatment liquid.
• hypobromous acid ion in the system in which hypobromous acid ion and hypochlorite ion coexist is the same as the above-described range.
• these oxidizing agents are within the above concentration range, as described above, it is possible to suppress the decomposition reaction of hypochlorous acid ions in the mixed solution and maintain the ruthenium form in which the ligand is easily coordinated. ..
• the content of the ligand coordinating with ruthenium in the ruthenium-containing gas generation inhibitor can be 0.0001 to 60% by mass, 0.01. It is more preferably to 35% by mass, and further preferably 0.1 to 20% by mass. As will be described later, this concentration can be adjusted so that the concentration of the ligand coordinating with ruthenium contained in the treatment liquid containing the gas generation inhibitor becomes a predetermined amount.
• the same pH adjuster as described above may be appropriately added.
• the content of the pH adjuster can be adjusted so that the pH of the treatment liquid containing the gas generation inhibitor is within a predetermined range.
• the content of the pH adjuster in the ruthenium-containing gas generation inhibitor may be an effective amount, and specifically, 0.000001 to 10% by mass can be exemplified.
• the method for suppressing the generation of ruthenium-containing gas is a method for suppressing the generation of ruthenium-containing gas, which comprises a step of adding the above-mentioned ruthenium-containing gas generation suppressing agent to a liquid for treating ruthenium.
• the present invention relates to a liquid (a liquid for treating ruthenium) used in a step of treating ruthenium such as an etching step, a residue removing step, a cleaning step, and a CMP step in a semiconductor manufacturing process.
• the generation of ruthenium-containing gas can be suppressed by using a ruthenium-containing gas generation inhibitor when cleaning ruthenium adhering to the inner wall of the chamber, piping, or the like.
• a ruthenium-containing gas generation inhibitor when cleaning ruthenium adhering to the inner wall of the chamber, piping, or the like.
• the ruthenium-containing gas of the present invention is added to a cleaning liquid used for removing ruthenium adhering to a chamber, piping, or the like.
• the generation inhibitor it is possible to suppress the ruthenium-containing gas generated during cleaning. According to this method, the generation of ruthenium-containing gas can be suppressed by the mechanism shown in the above description of the ruthenium-containing gas generation inhibitor.
• the concentration of one or more of the above-mentioned ligands coordinating with ruthenium in the treatment liquid containing the gas generation suppressing agent is 0.0001 to 60% by mass.
• the same pH adjusting agent as the above-mentioned pH adjusting agent may be appropriately added to the ruthenium-containing gas generation suppressing agent.
• the pH of the treatment liquid containing the gas generation inhibitor at 25 ° C. is, for example, 7-14. It can be adjusted as appropriate.
• the amount of the ruthenium-containing gas generation inhibitor added to the ruthenium treatment liquid depends on the amount of ruthenium dissolved in the treatment liquid containing the gas generation inhibitor.
• the amount of the ruthenium-containing gas generation inhibitor added is not particularly limited, but for example, when the amount of ruthenium dissolved in the liquid for treating ruthenium is 1, the weight ratio is preferably 1 to 10000, more preferably. It is 10 to 5000, more preferably 100 to 2000.
• the ruthenium-containing waste liquid treatment agent is a liquid that suppresses the generation of ruthenium-containing gas by being added to the ruthenium-containing waste liquid, and refers to a liquid containing a ligand that coordinates with ruthenium. Therefore, the ruthenium-containing semiconductor treatment liquid of the present invention can also be used as a treatment agent for ruthenium-containing waste liquid by utilizing its effect of suppressing the generation of ruthenium-containing gas.
• the ruthenium-containing waste liquid means a solution containing ruthenium even in a small amount.
• the ruthenium is not limited to ruthenium metal, it is sufficient include ruthenium element, for example, Ru, RuO 4 -, RuO 4 2-, RuO 4, such as RuO 2 and the like.
• the ruthenium-containing waste liquid for example, a liquid obtained by etching a semiconductor wafer containing ruthenium with an etching liquid having a composition different from that of the treatment liquid of the present invention, or a liquid of the present invention is used for treatment. The liquid after performing the above can be mentioned.
• an example thereof is a ruthenium-containing liquid generated by a semiconductor manufacturing process, chamber cleaning, or the like as described in the above-mentioned method for suppressing generation of ruthenium-containing gas.
• the waste liquid contains ruthenium even in a small amount, RuO 2 particles are generated via the RuO 4 gas, which contaminates the tank and piping, and accelerates the deterioration of the equipment by the oxidizing action of the RuO 2 particles. Further, RuO 4 gas generated from the waste liquid exhibit strong toxicity to the human body even at low concentrations. Thus, the ruthenium-containing waste liquid, to exert various adverse effects on devices such or human body, it is necessary to suppress the generation of RuO 4 gas is treated quickly.
• the type and content of the ligand coordinating with ruthenium, other components and their contents, pH and other conditions are described for the ruthenium of the present invention for semiconductors. The same conditions as described in the description of the treatment solution can be applied.
• the content of the ligand coordinating with ruthenium in the treatment agent for ruthenium-containing waste liquid can be 0.0001 to 60% by mass, 0.001. More preferably, it is in the amount of ⁇ 35% by mass. As will be described later, this concentration can be adjusted so that the concentration of the ligand coordinating with ruthenium in the mixed liquid when mixed with the ruthenium-containing waste liquid becomes a predetermined amount. Further, the same pH adjusting agent as the above-mentioned pH adjusting agent may be appropriately added to the treatment agent for the ruthenium-containing waste liquid.
• the content of the pH regulator can be adjusted so that the pH of the mixed solution when mixed with the ruthenium-containing waste liquid is within a predetermined range.
• the content of the pH adjuster in the treatment agent for the ruthenium-containing waste liquid may be an effective amount, and specifically, 0.000001 to 10% by mass can be exemplified.
• the method for treating a ruthenium-containing waste liquid of the present invention is a method for treating a ruthenium-containing waste liquid, which comprises a step of adding the above-mentioned ruthenium-containing waste liquid treatment agent to the ruthenium-containing waste liquid.
• the ruthenium-containing gas generated from the ruthenium-containing waste liquid can be suppressed by the mechanism shown in the above description of the ruthenium-containing gas generation inhibitor. Therefore, not only the handling of the ruthenium-containing waste liquid can be facilitated, but also the exhaust equipment and the exclusion equipment can be simplified, and the cost for treating the ruthenium-containing gas can be reduced. In addition, the risk of workers being exposed to the highly toxic ruthenium-containing gas is reduced, greatly improving safety.
• the concentration of one or more of the ligands coordinated with ruthenium in the mixed liquid of the ruthenium-containing waste liquid treatment agent and the ruthenium-containing waste liquid is, for example, 0. It is preferable to adjust the concentration of the ligand coordinating with ruthenium in the treatment agent for the ruthenium-containing waste liquid and the amount of the ligand added so as to be 0001 to 60% by mass. Further, in the method for treating the ruthenium-containing waste liquid, the same pH adjusting agent as the above-mentioned pH adjusting agent may be appropriately added to the treatment agent for the ruthenium-containing waste liquid.
• the pH of the mixed liquid when mixed with the ruthenium-containing waste liquid is, for example, 7-14. It can be adjusted as appropriate.
• the amount of the ruthenium-containing waste liquid treatment agent added to the ruthenium-containing waste liquid depends on the amount of ruthenium in the ruthenium-containing waste liquid.
• the amount of the treatment agent added to the ruthenium-containing waste liquid is not particularly limited.
• the weight ratio is preferably 1 to 10000, more preferably 10 to 5000, and further. It is preferably 100 to 2000.
• PH measurement method The pH of 10 mL of the treatment liquid prepared in Examples and Comparative Examples was measured using a tabletop pH meter (LAQUA F-73, manufactured by HORIBA, Ltd.). The pH measurement was carried out after the treatment liquid was prepared and stabilized at 25 ° C.
• the gas phase in the closed container was bubbled to the container containing the absorption liquid (1 mol / L NaOH), and the RuO 4 gas generated during the immersion in the Ru wafer was trapped in the absorption liquid. ..
• the amount of ruthenium in the absorbent solution was measured by ICP-OES, determine the amount of ruthenium of RuO 4 gas generated.
• the fact that all the ruthenium on the Si wafer immersed in the treatment liquid was dissolved was determined by measuring the sheet resistance before and after immersion with a four-probe resistance measuring instrument (Loresta-GP, manufactured by Mitsubishi Chemical Analytech Co., Ltd.). Confirmed by converting to thickness.
• Table 1 shows the composition of the treatment liquid and the evaluation results.
• the amount of ruthenium in Table 1 is a value obtained by dividing the weight of ruthenium contained in the absorption liquid of the ruthenium-containing gas by the area of the wafer with ruthenium.
• Comparing Comparative Examples 1 to 3 and Examples 1-3 it is understood that it is possible to reduce the generation amount of RuO 4 gas by the addition of the ligand in any of the pH. Further, from Example 4, when the treatment liquid to which the ligand was added was used at pH 13, the amount of ruthenium was 0 ⁇ g / cm 2 .
• the treatment liquid does not contain an oxidizing agent, but even in such a case, the generation of ruthenium-containing gas is suppressed.
• Examples 27 to 29 a heterocyclic compound containing nitrogen is used as a ligand that coordinates with ruthenium, but even in such a case, the generation of ruthenium-containing gas is suppressed.
• Examples 59 to 73> Preparation of a mixed solution of ruthenium-containing waste liquid and ruthenium-containing waste liquid treatment agent
• sodium hypochlorite manufactured by Wako Pure Chemical Industries, Ltd.
• ultrapure water a container made of fluororesin
• adjust the pH to the pH shown in Table 3 using HCl or an aqueous NaOH solution to obtain 2.0% by mass.
• a treatment liquid for ruthenium etching containing sodium hypochlorite was obtained.
• a 300 mm Si wafer on which ruthenium having a film thickness of 1360 ⁇ was formed was immersed in 1 L of the obtained treatment liquid at 25 ° C. until all the ruthenium was dissolved, and then the ruthenium-containing waste liquid was recovered in a waste liquid tank.
• a mixed solution (hereinafter, also simply referred to as a mixed solution) with a treatment agent for the contained waste liquid was obtained.
• a treatment liquid for ruthenium etching containing 4.0% by mass of sodium hypochlorite was obtained by the same method as in Example 59. 1 L of the obtained treatment liquid is poured onto the surface of a 300 mm Si wafer on which ruthenium having a film thickness of 2720 ⁇ is formed at 25 ° C. for 10 minutes, rinsed with 1 L of ultrapure water, and then the ruthenium-containing waste liquid is placed in a waste liquid tank.
• a treatment liquid for ruthenium etching containing 4.0% by mass of sodium hypochlorite was obtained by the same method as in Example 59. 1 L of the obtained treatment liquid was poured onto the surface of a 300 mm Si wafer on which ruthenium having a thickness of 1360 ⁇ was formed at 25 ° C. for 10 minutes, rinsed with 1 L of ultrapure water, and then collected in a waste liquid tank. , 6.0 ⁇ 10 -4 mol / L Ru was contained in the ruthenium-containing waste liquid shown in Table 4. For quantitative analysis of RuO 4 gas was carried out in the same manner as in Example 59.
• each treatment liquid shown in Table 5 was obtained according to the same procedure as in Example 1.
• the obtained treatment liquid was stored at 60 ° C., and the concentrations of hypochlorite ion and hypobromous acid ion after lapse of 5, 20, 40, and 60 hours were measured by the same method as in Example 1.
• the oxidant concentration at 0 hours was set to 100%, and the oxidant concentrations at each measurement time are summarized in Table 5.

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