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
• • 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
• • 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
  • H10P50/20—Dry etching; Plasma etching; Reactive-ion etching
  • H10P50/28—Dry etching; Plasma etching; Reactive-ion etching of insulating materials
  • H10P50/282—Dry etching; Plasma etching; Reactive-ion etching of insulating materials of inorganic materials
  • H10P50/283—Dry etching; Plasma etching; Reactive-ion etching of insulating materials of inorganic materials by chemical means
• • 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
  • H10P50/69—Etching of wafers, substrates or parts of devices using masks for semiconductor materials
  • H10P50/691—Etching of wafers, substrates or parts of devices using masks for semiconductor materials for Group V materials or Group III-V materials
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
  • Y02P10/00—Technologies related to metal processing
  • Y02P10/20—Recycling

Definitions

• the present invention relates to a method for removing lanthanum compounds and a treatment liquid for removing lanthanum compounds.
• Patent Document 1 discloses a removal treatment liquid for removing a high- ⁇ film from a silicon substrate. This removing treatment liquid contains fluoride ions.
• An object of the present invention is to provide a lanthanum compound removing method and a lanthanum compound removing treatment liquid capable of selectively removing lanthanum compounds from objects to be removed.
• one aspect of the present invention is as follows [1] to [11].
• the lanthanum compound is removed from the object by bringing a treatment liquid for removing the lanthanum compound into contact with the object having the lanthanum compound to be removed and the non-removal object not to be removed. and a removal step for The method for removing lanthanum compounds, wherein the treatment liquid for removing lanthanum compounds is an aqueous solution containing a salt of ⁇ -hydroxycarboxylic acid and having a pH of 5 or more and 10 or less.
• [6] The method for removing lanthanum compounds according to any one of [1] to [5], wherein the concentration of fluoride ions in the treatment liquid for removing lanthanum compounds is 0.5% by mass or less.
• [7] The method for removing lanthanum compounds according to any one of [1] to [6], wherein the concentration of hydrogen peroxide in the treatment liquid for removing lanthanum compounds is 5% by mass or less.
• a lanthanum compound removal treatment liquid that removes the lanthanum compound from the object to be treated by contacting the object to be treated having the lanthanum compound to be removed and the non-removal object not to be removed There is An aqueous solution containing a salt of ⁇ -hydroxycarboxylic acid and having a pH of 5 or more and 10 or less, wherein the content of the ⁇ -hydroxycarboxylic acid salt is 0.1% by mass or more and 60% by mass or less for removing lanthanum compounds. treatment liquid.
• an object having a lanthanum compound to be removed and a non-removal object not to be removed is brought into contact with a treatment liquid for removing lanthanum compounds.
• a removal step is provided for removing the lanthanum compound from the processed material.
• the treatment liquid for removing lanthanum compounds is an aqueous solution containing a salt of ⁇ -hydroxycarboxylic acid and having a pH of 5 or more and 10 or less.
• the lanthanum compound removal treatment liquid according to the present embodiment is brought into contact with an object having a lanthanum compound to be removed and a non-removal object not to be removed, whereby the lanthanum compound is removed from the object to be treated.
• the treatment liquid for removing lanthanum compounds according to the present embodiment is an aqueous solution containing a salt of ⁇ -hydroxycarboxylic acid and having a pH of 5 or more and 10 or less, and the content of the salt of ⁇ -hydroxycarboxylic acid is 0. .1% by mass or more and 60% by mass or less.
• the salt of ⁇ -hydroxycarboxylic acid has a chelating action on lanthanum
• the lanthanum compound-removing treatment liquid when the lanthanum compound-removing treatment liquid is brought into contact with the object to be treated, the lanthanum compound reacts with the ⁇ -hydroxycarboxylic acid in the lanthanum compound-removing treatment liquid. Forms a salt and a chelate and is removed from the material to be treated.
• some substances other than lanthanum compounds do not easily form chelates with ⁇ -hydroxycarboxylic acid salts.
• the portion becomes a non-removable object, and the non-removable object is hardly removed from the object even if the treatment liquid for removing the lanthanum compound is brought into contact with the object.
• the method for removing lanthanum compounds according to the present embodiment it is possible to selectively remove lanthanum compounds, which are objects to be removed, relative to objects not to be removed. Therefore, the method for removing a lanthanum compound according to this embodiment can be applied to the manufacture of electronic devices such as semiconductor elements.
• the lanthanum compound according to the present embodiment is applied to a substrate to which the lanthanum compound is attached (corresponding to the "processed object" which is a constituent element of the present invention).
• the removal method is applied, the salt of ⁇ -hydroxycarboxylic acid in the lanthanum compound removal treatment liquid forms a complex with the lanthanum compound through a chelating action, so the lanthanum compound adhering to the substrate is removed, and the surface of the substrate is removed. Cleansed.
• Lanthanum compound is an object to be removed by a lanthanum compound removing treatment liquid.
• Lanthanum compounds include, for example, lanthanum oxide, lanthanum nitride, and lanthanum oxynitride.
• Lanthanum oxide means a compound having lanthanum (La) and oxygen atoms (O) in its structure.
• Lanthanum nitride means a compound having lanthanum and nitrogen atoms (N) in its structure.
• Lanthanum oxynitride means a compound having lanthanum, oxygen and nitrogen atoms in its structure.
• a lanthanum compound may be used individually by 1 type, and may be used in combination of 2 or more type.
• lanthanum oxides include lanthanum oxide (La 2 O 3 ), lanthanum aluminate (LaAlO 3 ), lanthanum hafnate (La 2 Hf 2 O 7 ), and the like.
• Lanthanum nitrides include lanthanum nitride (LaN) and the like.
• Lanthanum oxynitrides include lanthanum titanate oxynitride (LaTiO 2 N) and the like.
• the lanthanum compound contains metals other than lanthanum, such as hafnium (Hf), zirconium (Zr), aluminum (Al), titanium (Ti), silicon (Si), etc., it can be an object to be removed.
• the content of lanthanum atoms contained in the lanthanum compound is , preferably 1 mol % or more, more preferably 10 mol % or more, even more preferably 15 mol % or more.
• the forms of lanthanum oxide, lanthanum nitride, and lanthanum oxynitride are not particularly limited, and may be, for example, film-like, foil-like, powdery, particulate, or block-like.
• Non-removable substances that are not targeted for removal by the treatment liquid for removing lanthanum compounds are not particularly limited as long as they are substances that hardly form chelates with salts of ⁇ -hydroxycarboxylic acid. Examples include silicon materials, Elementary metals other than lanthanum, oxides of metals other than lanthanum, nitrides of metals other than lanthanum, and oxynitrides of metals other than lanthanum are included.
• silicon materials include polysilicon (Si), amorphous silicon, silicon oxide, and silicon nitride.
• Silicon oxide refers to a compound containing silicon and oxygen in any proportion, and an example thereof is silicon dioxide (SiO 2 ).
• Silicon nitride refers to compounds containing silicon and nitrogen in any proportion, such as Si 3 N 4 .
• Examples of simple metals other than lanthanum include aluminum, hafnium, zirconium, and titanium.
• metal oxides other than lanthanum include aluminum oxide ( Al2O3 ), hafnium oxide ( HfO2 ), and zirconium oxide ( ZrO2 ).
• Examples of nitrides of metals other than lanthanum include titanium nitride (TiN).
• the non-removal object may be composed of one of the above substances, or may be composed of two or more.
• the non-removable object may contain a lanthanum compound, but the content is less than 1% by mass so that the non-removable object is difficult to remove with the treatment liquid for removing the lanthanum compound. is preferably 0.5% by mass or less, and even more preferably less than 0.1% by mass.
• the object to be removed is film-like or foil-like
• its thickness is preferably 0.1 nm or more, more preferably 1 nm or more, and even more preferably 5 nm or more.
• the minor axis thereof is preferably 1 nm or more, more preferably 10 nm or more, and even more preferably 100 nm or more. If the non-removable object has a size within the above range, it is difficult to remove with the treatment liquid for removing lanthanum compounds.
• Non-removable objects are, for example, substances that constitute electronic devices, and substances that are used in electronic devices as, for example, wiring materials, channel materials, gate materials, and barrier metals.
• the ratio of the lanthanum compound removal rate to the non-removal object removal rate is preferably 10 or more, more preferably 20 or more, and even more preferably 30 or more. If the removal rate ratio is 10 or more, it is possible to selectively remove lanthanum compounds while suppressing removal of non-removable objects.
• the treatment liquid for removing lanthanum compounds is an aqueous solution containing a salt of ⁇ -hydroxycarboxylic acid and having a pH of 5 or more and 10 or less.
• the pH of the treatment liquid for removing lanthanum compounds is 5 or more and 10 or less, preferably 5 or more and 9 or less, more preferably 7 or more and 9 or less, and even more preferably 7 or more and 8 or less. If the pH of the treatment liquid for removing lanthanum compounds is within the above numerical range, the removal of lanthanum compounds is facilitated.
• the pH of the treatment liquid for removing lanthanum compounds can be adjusted by adding a basic aqueous solution such as aqueous ammonia.
• the pH of the lanthanum compound-removing treatment liquid in the present invention is the pH at the temperature of the lanthanum compound-removing treatment liquid when it is in contact with the object to be treated in the removal step.
• ⁇ -hydroxycarboxylic acid salt is not particularly limited, and examples include ⁇ -hydroxycarboxylic acid ammonium salts, alkylammonium salts, arylammonium salts, lithium salts, sodium salts, potassium salts, and cesium salts. , calcium salts, and magnesium salts.
• An aqueous solution of an ⁇ -hydroxycarboxylic acid salt can be obtained by mixing an ⁇ -hydroxycarboxylic acid, a base and water to form an aqueous solution.
• the type of alkyl group of the alkylammonium salt is not particularly limited as long as the water solubility of the ⁇ -hydroxycarboxylic acid salt is higher than 2 g/100 mL-H 2 O, and for example, an alkyl group having 4 or less carbon atoms can be used. .
• the type of ⁇ - hydroxycarboxylic acid is not particularly limited as long as it can form a lanthanum compound chelate complex. 4 H 6 O 6 ), malic acid (C 4 H 6 O 5 ), glycolic acid (C 2 H 4 O 3 ), lactic acid (C 3 H 6 O 3 ), 2-methyllactic acid (C 4 H 8 O 3 ), tartronic acid (C 3 H 4 O 5 ), and quinic acid (C 7 H 12 O 6 ).
• citric acid, tartaric acid, malic acid, and lactic acid are preferred because of their high handling properties and high lanthanum compound-removing effect.
• ⁇ -hydroxycarboxylic acid salts described above one kind may be used alone, or two or more kinds may be used in combination.
• the content of the ⁇ -hydroxycarboxylic acid salt in the treatment liquid for removing lanthanum compounds is 0.1% by mass or more and 60% by mass or less, preferably 3% by mass or more and 60% by mass or less, and 5% by mass. It is more preferable that the content is at least 50% by mass or less.
• the removal rate of the lanthanum compound to be removed is high, which is more practical.
• the water solubility (g/100 mL-H 2 O) of the ⁇ -hydroxycarboxylic acid salt is preferably high, preferably 2 or more.
• the treatment liquid for removing lanthanum compounds may contain components other than the salt of ⁇ -hydroxycarboxylic acid.
• it may contain an oxidizing agent, a wetting agent, a surfactant, a coloring agent, an antifoaming agent, and the like.
• the treatment liquid for removing lanthanum compounds does not contain fluoride ions and hydrogen peroxide as much as possible.
• the concentration of fluoride ions in the treatment liquid for removing lanthanum compounds is preferably 1% by mass or less, more preferably 0.5% by mass or less, and further preferably 500 ppm by mass or less, 100 ppm by mass or less is particularly preferable.
• the concentration of hydrogen peroxide in the lanthanum compound-removing treatment liquid is preferably 5% by mass or less, more preferably 1% by mass or less, and even more preferably less than 100 ppm by mass. If the lanthanum compound-removing treatment liquid contains fluoride ions or hydrogen peroxide, the removal rate of the lanthanum compound may decrease, and in addition, objects to be removed may also be removed.
• the object to be treated includes objects to be removed (lanthanum compounds) to be removed by the lanthanum compound removal treatment liquid and non-removal objects not to be removed by the lanthanum compound removal treatment liquid.
• the type of object to be treated to which the lanthanum compound removal method according to the present embodiment can be applied is not particularly limited as long as it has a lanthanum compound that is an object to be removed and an object that is not to be removed. device.
• liquid crystal displays include liquid crystal displays, semiconductor elements such as metal-oxide-semiconductor field-effect transistors (MOSFET), MEMS (Micro Electro Mechanical Systems) elements, and hard disks.
• MOSFET metal-oxide-semiconductor field-effect transistors
• MEMS Micro Electro Mechanical Systems
• non-removable objects such as silicon oxide, silicon nitride, polysilicon, aluminum oxide, zirconium oxide, hafnium oxide, titanium nitride, etc. are hardly removed.
• the lanthanum compound can be removed with almost no adverse effects on the object to be treated.
• the method of bringing the lanthanum compound into contact with the lanthanum compound-removing treatment liquid is not particularly limited, but examples thereof include methods such as immersion, spraying, coating, and pouring. is mentioned.
• the immersion method is preferable from the viewpoint of simplification of an apparatus used for contacting the lanthanum compound with the treatment liquid for removing the lanthanum compound.
• the treatment conditions in the immersion method vary depending on the type of lanthanum compound and the composition of the treatment liquid for removing the lanthanum compound. It is preferably 100° C. or higher, more preferably 10° C. or higher and 90° C. or lower, and even more preferably 20° C. or higher and 80° C. or lower.
• the contact time (treatment time) between the lanthanum compound and the treatment liquid for removing the lanthanum compound is preferably 1 second or more and 180 minutes or less, more preferably 5 seconds or more and 90 minutes or less, and 10 seconds or more and 60 minutes or less. Minutes or less is more preferable.
• Such immersion treatment may be performed by simply immersing the object to be treated (for example, a substrate) having the lanthanum compound, which is the object to be removed, in the lanthanum compound-removing treatment solution. may be carried out by immersion in the lanthanum compound-removing treatment liquid in which the
• the object to be treated that has been subjected to the treatment to remove the lanthanum compound is washed with a cleaning liquid such as water, the salt of ⁇ -hydroxycarboxylic acid remaining on the surface of the object to be treated and contaminants containing the lanthanum compound can be removed. It can be removed from the object to be processed.
• a cleaning liquid such as water
• the type of cleaning liquid is not particularly limited, it is possible to clean with only water such as pure water, and there is no need to use an organic solvent such as alcohol. Since there is no need to use an organic solvent in the lanthanum compound-removing treatment liquid or cleaning liquid, the method for removing lanthanum compounds according to the present embodiment is less likely to adversely affect the human body and the environment.
• Example 1 An aqueous solution of triammonium citrate having a concentration of 5% by mass was prepared as a treatment liquid for removing lanthanum compounds.
• the pH of this treatment liquid for removing lanthanum compounds is 7.6 at 25°C.
• a 100 mL polypropylene container containing 40 mL of the lanthanum compound-removing treatment liquid was heated in a water bath to bring the temperature of the lanthanum compound-removing treatment liquid to 25°C.
• the concentration of fluoride ions in the treatment liquid for removing lanthanum compounds was less than 100 mass ppm.
• the types of thin films are a lanthanum oxide (La 2 O 3 ) film with a thickness of 100 nm, an aluminum oxide (Al 2 O 3 ) film with a thickness of 100 nm, a hafnium oxide (HfO 2 ) film with a thickness of 100 nm, and a film thickness of 100 nm.
• La 2 O 3 lanthanum oxide
• Al 2 O 3 aluminum oxide
• HfO 2 hafnium oxide
• the shape of this silicon substrate is a square with a side of 2 cm.
• the film thickness measurement conditions by the F20 film thickness measurement system are as follows. Table 1 shows the measurement results.
• Measurement pressure atmospheric pressure (101.3 kPa) Measurement temperature: 28°C Measurement atmosphere: in air Measurement wavelength range of lanthanum oxide: 250 to 950 nm Measurement wavelength range of aluminum oxide: 300 to 1200 nm Measurement wavelength range of hafnium oxide: 250 to 950 nm Measurement wavelength range of zirconium oxide: 250 to 930 nm Measurement wavelength range of titanium nitride: 150 to 1300 nm Measurement wavelength range for silicon dioxide: 200 to 1000 nm Measurement wavelength range of silicon nitride: 900 to 1700 nm Measurement wavelength range of polysilicon: 600 to 1100 nm
• Examples 2 to 15 and Comparative Examples 1 to 5 The composition of the treatment solution for removing lanthanum compounds (type and concentration of ⁇ -hydroxycarboxylic acid salt, type and concentration of additives, etc.), concentration of fluoride ions, pH at treatment temperature, treatment temperature, and treatment time are shown in the table. Etching was carried out in the same manner as in Example 1, except for the point described in 1., and the removal rate of each thin film was calculated. Table 1 shows the results.
• lanthanum oxide can be removed at a practical rate by using a triammonium citrate aqueous solution as a treatment liquid for removing lanthanum compounds. Also, the higher the temperature of the lanthanum compound-removing treatment liquid, the faster the removal rate, and the higher the concentration of triammonium citrate in the lanthanum compound-removing treatment liquid, the faster the removal rate.
• Example 9 when ammonium fluoride is contained in the treatment liquid for removing lanthanum compounds, lanthanum oxide is removed, but aluminum oxide, hafnium oxide, silicon dioxide, silicon nitride, poly The removal of silicon also progressed simultaneously. Also, lanthanum oxide was partially fluorinated to produce lanthanum fluoride, which remained on the silicon substrate.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Organic Chemistry (AREA)
• Materials Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Life Sciences & Earth Sciences (AREA)
• Emergency Medicine (AREA)
• Health & Medical Sciences (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Wood Science & Technology (AREA)
• Cleaning Or Drying Semiconductors (AREA)
• Removal Of Specific Substances (AREA)
• General Chemical & Material Sciences (AREA)
• Weting (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=86774382

Family Applications (1)

Country Status (4)

Citations (4)

• 2022
  • 2022-10-12 JP JP2023567562A patent/JPWO2023112453A1/ja active Pending
  • 2022-10-12 KR KR1020247019613A patent/KR20240121749A/ko active Pending
  • 2022-10-12 WO PCT/JP2022/038107 patent/WO2023112453A1/ja not_active Ceased
  • 2022-10-25 TW TW111140398A patent/TWI904389B/zh active

Patent Citations (4)

Also Published As

Similar Documents

Legal Events