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US-20260125588-A1 - POLISHING AGENT, POLISHING METHOD, METHOD FOR MANUFACTURING SEMICONDUCTOR COMPONENT, ADDITIVE SOLUTION FOR POLISHING AGENT, AND METHOD FOR MANUFACTURING ADDITIVE SOLUTION FOR POLISHING AGENT

US20260125588A1US 20260125588 A1US20260125588 A1US 20260125588A1US-20260125588-A1

Abstract

A polishing agent with excellent pH stability, an additive solution for a polishing agent for preparing the polishing agent and a method for manufacturing the same, a polishing method capable of performing high-speed polishing, and a method for manufacturing a semiconductor component using the polishing method are provided. A polishing agent contains (bi)carbonate of a primary amine, a secondary amine, a tertiary amine, or a quaternary ammonium, and water, in which an organic group that the amine or the ammonium has is a group selected from a linear alkyl group, a branched alkyl group, and an alkanol group, a content of the (bi)carbonate is 5 mmol/L to 130 mmol/L based on the whole polishing agent, a boiling point of the amine or the ammonium is 0° C. to 500° C., and pH is 7 to 11.

Inventors

  • Masatoshi AKAJI

Assignees

  • AGC Inc.

Dates

Publication Date
20260507
Application Date
20260105
Priority Date
20230707

Claims (14)

  1. 1 . A polishing agent containing: abrasive grains; and (bi)carbonate of a primary amine, a secondary amine, a tertiary amine, or a quaternary ammonium, and water, wherein an organic group that the amine or the ammonium has is a group selected from a linear alkyl group, a branched alkyl group, and an alkanol group, a content of the (bi)carbonate is 5 mmol/L to 130 mmol/L based on the whole polishing agent, a boiling point of the amine or the ammonium is 0° C. to 500° C., and pH is 7 to 11.
  2. 2 . The polishing agent according to claim 1 , wherein a molecular weight of the (bi)carbonate is 500 or less.
  3. 3 . The polishing agent according to claim 1 , wherein a melting point of the amine or the ammonium is −180° C. to 0° C.
  4. 4 . The polishing agent according to claim 1 , wherein an absolute value of a difference between pKa of ammonium ions in the (bi)carbonate and pH of the polishing agent is 3 or less.
  5. 5 . The polishing agent according to claim 1 , wherein the organic group includes an alkanol group.
  6. 6 . The polishing agent according to claim 1 , wherein the (bi)carbonate includes (bi)carbonate of a tertiary amine.
  7. 7 . The polishing agent according to claim 1 , wherein the abrasive grains include at least one type selected from the group consisting of silica particles, alumina particles, zirconia particles, cerium compound particles, titania particles, germania particles, composite particles thereof, and core shell-type particles.
  8. 8 . The polishing agent according to claim 2 , wherein the abrasive grains include cerium compound particles.
  9. 9 . The polishing agent according to claim 2 , wherein the abrasive grains include ceria particles.
  10. 10 . The polishing agent according to claim 1 , wherein a content of the abrasive grains is 0.01 wt. % to 10.0 wt. % based on a total weight of the polishing agent.
  11. 11 . A polishing method in which a polishing pad is brought into contact with a surface to be polished of a semiconductor substrate while supplying a polishing agent therebetween, and the surface to be polished is polished by relative motion of the surface to be polished and the polishing pad, wherein the polishing agent is the polishing agent according to claim 1 .
  12. 12 . A method for manufacturing a semiconductor component, wherein the semiconductor component is obtained by dividing a semiconductor substrate having a surface to be polished, polished by the polishing method according to claim 11 into pieces.
  13. 13 . An additive solution for a polishing agent containing (bi)carbonate of a primary amine, a secondary amine, a tertiary amine, or a quaternary ammonium, and water, wherein an organic group that the amine or the ammonium has is a group selected from a linear alkyl group, a branched alkyl group, and an alkanol group.
  14. 14 . A method for manufacturing the additive solution for the polishing agent according to claim 13 , the method comprising: dissolving a primary amine, a secondary amine, a tertiary amine, or a quaternary ammonium salt in water; and supplying carbon dioxide gas to the water to generate (bi)carbonate.

Description

INCORPORATION BY REFERENCE This application is based upon and claims the benefit of priority from Japanese patent application No. 2023-112030, filed on Jul. 7, 2023, and PCT application No. PCT/JP2024/022814 filed on Jun. 24, 2024, the disclosure of which is incorporated herein in its entirety by reference. BACKGROUND The present invention relates to a polishing agent, a polishing method, a method for manufacturing a semiconductor component, an additive solution for a polishing agent, and a method for manufacturing an additive solution for a polishing agent. As packing densities of semiconductor integrated circuits increase and their functions become more sophisticated, the development of microfabrication technology for making structures of semiconductor elements finer and more densified has been progressing. In the manufacturing of semiconductor integrated circuit devices (hereinafter also referred to as semiconductor devices), conventionally, interlayer insulating films, buried wiring lines, and the like are flattened by using Chemical Mechanical Polishing (hereinafter referred to as CMP) in order to prevent a problem that irregularities (differences in level) on the surface of a layer exceed the focal depth of lithography and hence a sufficient resolution cannot be obtained. As the demand for making elements more precise and finer is increasing, the importance of high flatness obtained by CMP is increasing more and more. Further, in the manufacture of semiconductor devices, shallow trench isolation (STI: Shallow Trench Isolation) in which an element isolation width is small has been introduced in order to make semiconductor devices finer even further. STI is a method for forming an electrically insulated element region by forming a trench (groove) in a silicon substrate and embedding an insulating film in the trench. An example of STI will be described with reference to FIGS. 1A and 1B. In this example, first, as shown in FIG. 1A, an element region on a silicon substrate 1 is masked with a stopper film 2. Then, a trench 3 is formed in the silicon substrate 1, and an insulating film such as a silicon oxide film 4 is deposited so as to fill the trench 3 therewith. Next, by CMP, while leaving the part of the silicon oxide film 4 located inside the trench 3, which is a recessed part, the remaining part of the silicon oxide film 4 located over the stopper film 2, which is a protruding part(s), is polished and thereby removed. By doing so, an element isolation structure in which the silicon oxide film 4 is embedded in the trench 3 is obtained as shown in FIG. 1B. As an example of the polishing agent used for CMP, Patent Literature 1 discloses a polishing agent containing cerium oxide particles, water-soluble polyamine, potassium hydroxide, and an organic acid and having pH of 10 or more. Patent Literature 1: Japanese Unexamined Patent Application Publication No. 2016-154208 SUMMARY It is known that the polishing performance of the polishing agent varies depending on pH changes. In order to stabilize the performance of the polishing agent, a polishing agent with excellent pH stability has been required. In particular, an alkaline polishing agent tends to become acidic as it absorbs carbon dioxide gas in the air, which causes a problem that the polishing performance is unlikely to be stable. In view of the above-described problem, an object of the present disclosure is to provide a polishing agent with excellent pH stability, an additive solution for a polishing agent for preparing the polishing agent and a method for manufacturing the same, a polishing method capable of performing high-speed polishing, and a method for manufacturing a semiconductor component using the polishing method. The present disclosure provides a polishing agent, a polishing method, a method for manufacturing a semiconductor component, an additive solution for a polishing agent, and a method for manufacturing an additive solution for a polishing agent. [1] A polishing agent containing: abrasive grains; and(bi)carbonate of a primary amine, a secondary amine, a tertiary amine, or a quaternary ammonium, and water, whereinan organic group that the amine or the ammonium has is a group selected from a linear alkyl group, a branched alkyl group, and an alkanol group, . . . ,a content of the (bi)carbonate is 5 mmol/L to 130 mmol/L based on the whole polishing agent,a boiling point of the amine or the ammonium is 0° C. to 500° C., andpH is 7 to 11. [2] The polishing agent described in Item [1], wherein a molecular weight of the (bi)carbonate is 500 or less.[3] The polishing agent described in Item [1] or [2], wherein a melting point of the amine or the ammonium is −180° C. to 0° C.[4] The polishing agent described in any one of Items [1] to [3], wherein an absolute value of a difference between pka of ammonium ions in the (bi)carbonate and pH of the polishing agent is 3 or less.[5] The polishing agent described in any one of Items