CN-122010065-A - Preparation method of hydroxylamine aqueous solution suitable for semiconductor field

Abstract

The invention discloses a preparation method of hydroxylamine aqueous solution suitable for the field of semiconductors, which comprises the steps of (1) adding inorganic alkali aqueous solution into hydroxylamine aqueous solution until the pH value of the hydroxylamine aqueous solution reaches 9-11 to obtain hydroxylamine aqueous solution crude product, (2) adding organic solvent into the hydroxylamine aqueous solution crude product, adding the organic solvent to change the solubility of salt-containing components, crystallizing and separating out, removing salt-containing solids by solid-liquid separation to obtain desalted hydroxylamine solution, (3) carrying out reduced pressure distillation on the desalted hydroxylamine solution to remove the organic solvent, simultaneously utilizing the organic solvent and water to realize concentration promotion of hydroxylamine in an azeotropic manner to obtain hydroxylamine aqueous solution after removing the organic solvent, and (4) purifying the hydroxylamine aqueous solution after removing the organic solvent by ion exchange resin to remove trace metal ion impurities and anion impurities in the solution to obtain hydroxylamine aqueous solution suitable for the field of semiconductors.

Inventors

• LU PING
• BAO ZONGBI
• CAO YIFENG
• Huang Gongyue
• REN QILONG

Assignees

• 浙江大学衢州研究院

Dates

Publication Date

20260512

Application Date

20260204

Claims (10)

1. 1. The preparation method of the hydroxylamine aqueous solution suitable for the semiconductor field is characterized by comprising the following steps: (1) Adding an inorganic alkali aqueous solution into the hydroxylamine salt aqueous solution until the pH value of the hydroxylamine salt solution reaches 9-11 to obtain a hydroxylamine aqueous solution crude product; (2) Adding an organic solvent into the hydroxylamine aqueous solution crude product, wherein the addition of the organic solvent changes the solubility of the salt-containing component, and then crystallizing and separating out, and removing salt-containing solids through solid-liquid separation to obtain a desalted hydroxylamine solution; (3) The desalted hydroxylamine solution is subjected to reduced pressure distillation to remove the organic solvent, and meanwhile, the concentration of the hydroxylamine is improved by utilizing the azeotropy of the organic solvent and water to obtain the hydroxylamine aqueous solution from which the organic solvent is removed; (4) Purifying the hydroxylamine aqueous solution from which the organic solvent is removed by ion exchange resin, and removing trace metal ion impurities and anion impurities in the solution to obtain the hydroxylamine aqueous solution applicable to the semiconductor field.
2. 2. The method according to claim 1, wherein in the step (1), the hydroxylamine salt comprises one or more of hydroxylamine hydrochloride, hydroxylamine sulfate, hydroxylamine phosphate and hydroxylamine nitrate.
3. 3. The method according to claim 1, wherein in the step (1), the inorganic base comprises at least one of sodium hydroxide and potassium hydroxide.
4. 4. The preparation method according to claim 1, wherein in the step (2), the addition volume of the organic solvent is 1 to 20 times the volume of the crude hydroxylamine aqueous solution.
5. 5. The method according to claim 1, wherein in the step (2), the organic solvent comprises one or more of methanol, ethanol, propanol, and isopropanol.
6. 6. The production method according to claim 1, wherein in the step (3), the distillation pressure of the reduced pressure distillation is 100 to 1000pa, and the distillation temperature is 20 to 100 ℃.
7. 7. The method according to claim 1, wherein in the step (4), the ion exchange resin comprises one or more of an H-type cation exchange resin, an OH-type anion exchange resin, and an H/OH-type mixed bed ion exchange resin.
8. 8. The method according to claim 1, wherein in the step (4), the metal ion impurities include one or more of lithium ion, sodium ion, magnesium ion, aluminum ion, potassium ion, calcium ion, titanium ion, vanadium ion, chromium ion, manganese ion, iron ion, cobalt ion, nickel ion, copper ion, zinc ion, molybdenum ion, silver ion, tin ion, barium ion, selenium ion, zirconium ion, mercury ion, and cadmium ion.
9. 9. The method according to claim 1, wherein in the step (4), the anionic impurities include one or more of nitrate ions, sulfate ions, phosphate ions, and chloride ions.
10. 10. The method according to claim 1, wherein in the step (4), the hydroxylamine mass fraction in the aqueous hydroxylamine solution suitable for the semiconductor field is not less than 50%, the content of single metal ion is less than 5 ppb, and the anion concentration is less than 500 ppb.

Description

Preparation method of hydroxylamine aqueous solution suitable for semiconductor field Technical Field The invention relates to the field of preparation and purification of high-purity and high-concentration hydroxylamine aqueous solution, in particular to a preparation method of hydroxylamine aqueous solution applicable to the field of semiconductors. Background Hydroxylamine is an important chemical intermediate and is applied to the fields of fine chemical engineering such as medicines, pesticides, textiles, electronics and the like. The hydroxylamine aqueous solution with high purity and high concentration is widely applied to the field of semiconductor manufacturing, is mainly used for post-CMP cleaning, photoresist stripping and metal surface treatment of copper/cobalt interconnection in a semiconductor process, and has the characteristics of selectively removing oxides without corroding metals, being low in corrosiveness, being environment-friendly and the like. In the field of semiconductor manufacturing, hydroxylamine aqueous solutions are required to reach 50% concentration, and trace impurities in the solutions are strictly required, including metal ion and anion impurities. However, hydroxylamine monomers contain N, O heteroatoms, and these electron-rich heteroatoms coordinate with metal ions to form stable complexes, which makes removal of metal ions difficult. In addition, hydroxylamine monomer is unstable and easy to decompose, and the decomposition rate is accelerated under the conditions of higher concentration, high temperature and the like, so that the final hydroxylamine yield is reduced. Patent specification with publication number CN120987276A discloses a preparation method of an ultra-high purity hydroxylamine aqueous solution, which comprises the steps of preparing a hydroxylamine aqueous solution crude product through neutralization reaction of hydroxylamine salt and organic alkali, and then preparing the ultra-high purity hydroxylamine aqueous solution through membrane separation and evaporation concentration. Patent specification with publication number CN117416933A discloses a method for preparing hydroxylamine aqueous solution by hydroxylamine salt neutralization, which comprises the steps of neutralizing, and then carrying out reduced pressure distillation to obtain the hydroxylamine aqueous solution. Patent specification with publication number CN101049919A discloses a production method of high-purity hydroxylamine free alkali and aqueous solution thereof, which is prepared by thermal decomposition and sublimation of hydroxylamine phosphate. Patent specification publication No. CN1209108A discloses a process for producing an aqueous solution of free hydroxylamine, which comprises preparing a crude aqueous solution of hydroxylamine by acid-base neutralization, and separating the aqueous solution of hydroxylamine from the salt-containing component by distillation. In the preparation method of the hydroxylamine aqueous solution, heating is adopted to increase the concentration of the hydroxylamine monomer in the hydroxylamine aqueous solution or purify the hydroxylamine aqueous solution, and a large amount of hydroxylamine monomer is severely decomposed at a higher heating temperature, so that the final hydroxylamine yield is low, and a large amount of gas is generated by the decomposition of the hydroxylamine monomer, thereby having a larger influence on the safety of the production flow. In addition, although a high-concentration hydroxylamine aqueous solution can be prepared by a simple neutralization reaction and distillation method, trace impurities are difficult to remove, and a high-purity high-concentration hydroxylamine aqueous solution suitable for the field of semiconductor manufacturing cannot be obtained. Disclosure of Invention Aiming at the technical problems and the defects in the field, the invention provides a preparation method of hydroxylamine aqueous solution suitable for the field of semiconductors. The method takes hydroxylamine salt as a raw material, generates hydroxylamine aqueous solution through acid-base neutralization reaction, adjusts the mixing proportion of an organic solvent and the aqueous solution to realize crystallization and remove salt components in the hydroxylamine aqueous solution, improves the concentration of the hydroxylamine by azeotropic distillation of the organic solvent and water, and removes residual metal ions and anions in the hydroxylamine aqueous solution by resin adsorption. The method of the invention realizes the preparation of high-purity and high-concentration hydroxylamine aqueous solution (hydroxylamine mass fraction is more than 50%, single metal ion content is less than 5 ppb, and anion concentration is less than 500 ppb) suitable for the semiconductor field. By means of crystallization desalination and azeotropic distillation assisted by an organic solvent, the mild desalination and concentration of the hydroxylamin