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KR-20260064333-A - CLEAN COMPOSITION FOR CERIA ABRASIVE PARTICLES

KR20260064333AKR 20260064333 AKR20260064333 AKR 20260064333AKR-20260064333-A

Abstract

The present invention relates to a composition for cleaning ceria abrasive particles, comprising a phosphate-based compound, an ammonium-based compound, and an amino acid-based zwitterion compound, wherein the amino acid-based zwitterion compound comprises a trialkylammonium alkyl carboxylate-based compound, and has a pH of 10 to 13.

Inventors

  • 황샘
  • 김찬미
  • 이재성

Assignees

  • 솔브레인 주식회사

Dates

Publication Date
20260507
Application Date
20241031

Claims (12)

  1. It includes phosphate compounds, ammonium compounds, and amino acid zwitterion compounds, and The above amino acid-based amphoteric ionic compound includes a trialkylammonium alkyl carboxylate-based compound, A composition for cleaning ceria abrasive particles having a pH of 10 to 13.
  2. In claim 1, A composition for cleaning ceria abrasive particles, comprising one or more phosphate compounds selected from the group consisting of phosphoric acid, phosphorous acid, hypophosphorous acid, trimethyl phosphate, phenylphosphonic acid, nitrilotris(methylene phosphonic acid), N,N,N,'N'-ethylenediamine-tetrakis(methylene phosphonic acid), and hydroxyethane-1,1-diphosphonic acid.
  3. In claim 1, The above ammonium-based compound is a composition for cleaning ceria abrasive particles, comprising an ammonium hydroxide salt-based compound.
  4. In claim 3, The above ammonium hydroxide salt-based compound is a composition for cleaning ceria abrasive particles, comprising tetraalkylammonium hydroxide.
  5. In claim 3, A composition for cleaning ceria abrasive particles, comprising one or more ammonium hydroxide salt-based compounds selected from the group consisting of tetramethylammonium hydroxide, tetraethylammonium hydroxide, ammonium hydroxide, tetrabutylammonium hydroxide, and benzyltrimethylammonium hydroxide.
  6. In claim 1, The above amino acid-based amphoteric ionic compound comprises a compound represented by the following formula (1), a composition for cleaning ceria abrasive particles. (In the above formula (1), R1 , R2 , and R3 are each independently hydrogen or an aliphatic alkyl group having 1 to 3 carbon atoms, and may be the same or different from each other, and L is an alkylene group having 1 to 10 carbon atoms that may have at least one of an aliphatic alkyl group having 1 to 6 carbon atoms, a hydroxyl group, a thiol group, a thioalkoxy group, an amino group, an amide group, a carboxyl group, an aromatic allocyclic group, and an aromatic heterocyclic group as a substituent, and R1 , R2 , and R3 may each be connected to each other to form a loop, or any one of R1 , R2 , and R3 may be connected to L to form a loop.
  7. In claim 6, A composition for cleaning ceria abrasive particles, wherein the above-mentioned amino acid-based amphoteric ionic compound comprises one or more selected from the group consisting of glycine, trimethylglycine, alanine, valine, leucine, isoleucine, proline, asparagine, serine, thionine, glutamine, cysteine, methionine, phenylalanine, tyrosine, tryptophan, aspartic acid, glutamic acid, histidine, lysine, and arginine.
  8. In claim 1, A composition for cleaning ceria abrasive particles, comprising 100 parts by weight of an ammonium-based compound, 5 to 500 parts by weight of a phosphate-based compound, and 5 to 500 parts by weight of an amino acid-based amphoteric ionic compound.
  9. In claim 1, A composition for cleaning ceria abrasive particles, further comprising an organic acid comprising one or more aliphatic or aromatic carboxylic acid compounds selected from the group consisting of monocarboxylic acids, dicarboxylic acids, and tricarboxylic acids that may be substituted with at least one halogen atom.
  10. In claim 9, A composition for cleaning ceria abrasive particles, wherein the above organic acid comprises a fluorinated aliphatic carboxylic acid compound.
  11. In claim 1, A composition for cleaning ceria abrasive particles having a pH of 10.5 to 13.
  12. In any one of claims 1 to 11, A composition for cleaning ceria abrasive particles, used to clean ceria abrasive particles having an average particle diameter (D 50 ) of 150 nm or less.

Description

Clean composition for ceria abrasive particles The present invention relates to a composition for cleaning ceria abrasive particles, and more specifically, to a cleaning composition for cleaning ceria particles used in a Chemical Mechanical Polishing (CMP) process. The wiring process, which is one of the manufacturing processes for semiconductor devices, includes a step of depositing a metal layer in grooves formed on a substrate (e.g., a semiconductor wafer) by embedding metal materials such as tungsten, copper, or aluminum into the grooves. After this metal layer deposition step, it is common practice to perform a chemical mechanical polishing (CMP) process and a cleaning process to remove (etch) unnecessary parts of the deposited metal layer. In the CMP process, a slurry composition containing abrasives such as silica particles or ceria particles is typically used. If abrasives remain on the substrate after the CMP process, problems may arise that cause issues with the structure and characteristics of the semiconductor device or degrade the manufacturing yield and/or the quality of the manufactured product. To prevent these problems, a cleaning process is performed to remove the abrasives remaining on the substrate. Ceria, an abrasive used in the CMP process, exhibits a higher removal rate (RR) and selectivity relative to low concentration compared to silica, but cleaning after polishing has been difficult. Accordingly, methods have been proposed to clean ceria polishing particles by using diluted hydrofluoric acid (HF) or ammonia, or by using SPM (Sulfuric acid Peroxide Mixture), a mixture of sulfuric acid and hydrogen peroxide, as a cleaning solution (refer to Korean Registered Patent No. 712980 [Patent Document 1] and Korean Registered Patent No. 1187341 [Patent Document 2]). However, when using diluted hydrofluoric acid (DHF) in the cleaning process, there were problems such as increased surface roughness or defects occurring on the substrate surface due to damage. Additionally, although SPM is a cleaning solution with excellent cleaning capabilities, it contains sulfuric acid, a strong acid, which posed a problem of causing serious environmental pollution upon disposal and posing a risk to workers. Therefore, there is a need for a cleaning composition that can remove residues of the slurry composition, abrasive particles, organic contaminants, metal contaminants, etc. generated after the CMP process without causing defects on the substrate surface, is environmentally friendly, and has reduced risk to the human body. The present invention will be described in detail below. In the present invention, "ceria particles" refers to cerium-based abrasive particles that include, for example , cerium oxide having the chemical formulas Ce₂O₃ and CeO₂ and can be included in a slurry during chemical mechanical polishing. In addition, in the present invention, "average particle size" is measured by a conventional method known in the art, and may be, for example, the particle size of the 50% cumulative distribution (D 50 ) in the particle size distribution map measured using a particle size analyzer (PSA). Furthermore, in the present invention, "zwitterion" refers to an ionic compound that contains equal amounts of positively charged functional groups and negatively charged functional groups within the molecule, thereby exhibiting overall electrical neutrality. Cleaning composition The composition for cleaning ceria abrasive particles according to the present invention comprises a phosphate-based compound, an ammonium-based compound, and an amino acid-based zwitterion compound. At this time, the cleaning composition has a high pH of 10 to 13, so that the surface potential of the ceria and the surface potential of the silicon oxide film have a negative value, and thus the repulsive force prevents re-adsorption. Specifically, the cleaning composition may have a pH of 10.5 to 13, or 11 to 13. In addition, the above cleaning composition has the advantage of excellent cleaning effect on silicon oxide films by removing Ce-O-Si bonds on the cleaning surface. ammonium compounds Ammonium compounds increase the ceria cleaning power of the composition by inducing a reduction reaction on the surface of ceria particles, causing the ceria particles to carry a negative charge, and increase the removal rate of ceria particles by inducing slight etching of the silicon film substrate, thereby removing the strong chemical bond of Si-O-Ce. The above ammonium-based compound may include an ammonium hydroxide salt-based compound. Specifically, the ammonium hydroxide salt-based compound may include tetraalkylammonium hydroxide. For example, the above ammonium hydroxide salt-based compound may include one or more ammonium hydroxide salt-based compounds selected from the group consisting of tetramethylammonium hydroxide, tetraethylammonium hydroxide, ammonium hydroxide, tetrabutylammonium hydroxide, and benzyltrimethylammonium hydroxide. S