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CN-117721474-B - Cleaning agent for chip after chemical mechanical polishing, preparation method and application thereof

CN117721474BCN 117721474 BCN117721474 BCN 117721474BCN-117721474-B

Abstract

The invention relates to a cleaning agent for chips after chemical mechanical polishing, which comprises, by weight, 1-10 parts of a functional agent, 0.1-0.5 part of a corrosion inhibitor, 1-5 parts of an additive, 1-10 parts of amide and 80-90 parts of ultrapure water. The invention uses the strong chelating ability of the functional agent to copper ions to remove copper ions, and uses the preferential adsorption characteristic of the corrosion inhibitor to form a protective film on the copper surface to inhibit the corrosion of the cleaning agent to the copper surface. The composite use of the two components effectively removes copper oxide on the premise of not corroding the copper surface. In addition, the carbobenzoxy in the additive can also protect the amino in the functional agent from being destroyed so as to ensure the stable existence of the copper surface protection film.

Inventors

  • HOU JUN
  • LV JING
  • REN HAONAN
  • LIU WEN
  • LAI XIN

Assignees

  • 江苏奥首材料科技有限公司

Dates

Publication Date
20260505
Application Date
20231219

Claims (7)

  1. 1. The cleaning agent for the chip after chemical mechanical polishing is characterized by comprising the following components in parts by weight: 1-10 parts of functional agent; 0.1-0.5 part of corrosion inhibitor; 1-5 parts of an additive; 1-10 parts of amide; 80-90 parts of ultrapure water; the functional agent is one or more of 6-hydroxyquinoxaline, 2-bromoquinoxaline, 2- (4-bromophenyl) quinoxaline, 4-quinoxaline-2-yl-aniline and 2- (2' -quinoxalinyl) -4, 5-tetramethyl imidazoline-3-oxidation-1-oxygen radical); the corrosion inhibitor is one or more of 3 '-chloromethyl-4' -hydroxyacetophenone, 4-benzyloxy-3-nitroacetophenone and 1- {4- (acetoxy) -3- [ (acetoxy) methyl ] phenyl } ethanone; The additive is one or more of N-acetyl-L-proline, N- (2, 4-dinitrobenzene) -L-proline, N- [3- (acetylmercapto) - (2S) -methylpropanoyl ] -L-proline and N-carbobenzoxy-L-proline.
  2. 2. The post-CMP cleaner of claim 1, wherein the functional agent is a 2- (2' -quinoxalinyl) -4, 5-tetramethylimidazoline-3-oxide-1-oxy radical having the following structure: 。
  3. 3. The post-cmp cleaning agent of claim 1 wherein: The amide is one or more of formamide, acetamide, propionamide, butyramide and isobutyramide.
  4. 4. The post-cmp cleaning agent of claim 3 wherein: the corrosion inhibitor is 1- {4- (acetoxyl) -3- [ (acetoxyl) methyl ] phenyl } ethanone; The additive is N-carbobenzoxy-L-proline; the amide is isobutyramide.
  5. 5. A method for preparing the cleaning agent after chemical mechanical polishing of a chip according to any one of claims 1 to 4, comprising the steps of: Step 1, respectively weighing each component with the respective dosage; And 2, sequentially adding a functional agent, amide, an additive, a corrosion inhibitor and ultrapure water into a container, sealing, performing ultrasonic treatment at 25-50 ℃ by using 80KHz, and performing complete dissolution for 0.5-1h to obtain the cleaning agent after chemical mechanical polishing of the chip.
  6. 6. A method for cleaning the post-cmp cleaning agent for chips according to any one of claims 1 to 4, comprising the steps of: Preparing an aqueous solution with the mass percent concentration of 10-30% from the prepared cleaning agent after the chemical mechanical polishing of the chip, and then soaking the semiconductor chip in the aqueous solution at the temperature of 25-50 ℃ for 2-15h to obtain the soaked semiconductor chip; And 2, placing the soaked semiconductor chip into ultrapure water to be washed at least twice, thus completing the cleaning treatment of the semiconductor chip.
  7. 7. Use of the post-cmp cleaning agent of any one of claims 1-4 for cleaning semiconductor chips.

Description

Cleaning agent for chip after chemical mechanical polishing, preparation method and application thereof Technical Field The invention belongs to the field of semiconductor manufacturing processes, and particularly relates to a cleaning agent for chips after chemical mechanical polishing, a preparation method and application thereof. Background Currently, as feature sizes of semiconductor device designs become smaller, copper has been widely used for interconnects of semiconductor devices, and in conventional multi-layer copper interconnect processes, a main step in fabricating one layer of copper interconnect is to perform copper film deposition in a trench, then Chemical Mechanical Polishing (CMP), then cleaning after polishing, and finally deposition of a barrier/dielectric layer to prepare for fabricating the next layer of copper interconnect. Although the above-mentioned steps such as CMP are performed in a clean room, many contaminant particles remain on the surface of the chip after the CMP process, and these particles originate from the polishing liquid, the polishing pad, and the polished copper particles themselves, and Cu and CuO contaminant particles therein have a great influence on the chip, so that two copper wires that should not be conducted are electrically connected, thereby causing a short circuit. Copper also has two characteristics, one of which is readily oxidized to CuO in an environment containing O 2 and the other of which is hydrophilic, the pure copper surface is fully wettable by water to form a film of water. In this way, when the chip surface rotating at a high speed is wetted with the pure water liquid at the time of the next cleaning step, the brush slides on the water film of the chip surface without directly contacting the chip surface when the cleaning brush approaches, but the pure water in the form of a film moves at a high speed on the chip surface, and the contaminant particles on the chip surface are removed by the frictional force generated thereby. However, once the copper surface is oxidized into CuO, the copper surface becomes water repellent and does not stick to water, a water film cannot be formed, and at this time, the brush is just in direct contact with the chip surface when the copper surface is cleaned by the brush, so that particles originally attached to the brush are attached to the chip surface again, and secondary pollution is caused. The disadvantage of the prior art is firstly that the cleaning agents are not only aimed at removing CuO, but also have a corrosive action on Cu wires, resulting in a rough surface, which makes them severely limited in terms of cleaning temperature, concentration and time, generally only between tens of seconds and tens of minutes, while the subsequent deposition step cannot be carried out immediately, so that the chip is only first placed in an environment containing O 2 for the next deposition step. For these reasons, the chip can only be placed in an environment containing O 2 for at most 4 hours, that is, the production condition of the next deposition step must be prepared within 4 hours, the surface of the chip is oxidized to form a CuO film exceeding the thickness limit for any reason, and the re-deposition of the barrier layer on the CuO film can cause destructive damage to the IC device, because CuO will increase the impedance of the circuit or break the circuit between the metal layers, even if the chip has to be scrapped in some cases, which causes great inconvenience to the production and also greatly affects the yield. In summary, if CuO can be removed as soon as possible after the copper CMP step, the waiting time between the copper CMP step and the subsequent barrier layer deposition step can be shortened, which will bring great convenience to production. Disclosure of Invention The invention solves the technical problems that CuO cannot be removed as soon as possible after a copper Chemical Mechanical Polishing (CMP) step, and the waiting time between the copper CMP step and a subsequent barrier layer deposition step is too long. In view of the technical problems in the prior art, the invention designs a cleaning agent for chips after chemical mechanical polishing, a preparation method and application thereof. In order to solve the technical problems, the invention adopts the following scheme: the cleaning agent for the chip after chemical mechanical polishing is characterized by comprising the following components in parts by weight: 1-10 parts of functional agent; 0.1-0.5 part of corrosion inhibitor; 1-5 parts of an additive; 1-10 parts of amide; 80-90 parts of ultrapure water; Wherein the functional agent is a quinoxaline derivative; The corrosion inhibitor is a p-hydroxyacetophenone derivative; the additive is L-proline derivative. Further, the functional agent is one or more of 6-hydroxyquinoxaline, 2-bromoquinoxaline, 2- (4-bromophenyl) quinoxaline, 4-quinoxaline-2-yl-aniline and 2- (2' -quinoxaliny