KR-20260066097-A - Polishing liquid and polishing method

Abstract

A polishing solution comprising abrasive particles and an acid component, wherein the acid component comprises at least one compound selected from the group consisting of sulfo groups and sulfonate groups (excluding sulfuric acid and its salts), and having a pH greater than 4.5. A polishing method comprising a process of polishing a surface to be polished using said polishing solution.

Inventors

• 이이쿠라 다이스케
• 하기와라 마이
• 후쿠다 신타로

Assignees

• 가부시끼가이샤 레조낙

Dates

Publication Date

20260512

Application Date

20240910

Priority Date

20230912

Claims (14)

1. Contains abrasive particles and acidic components, The above acid component comprises a compound having at least one selected from the group consisting of a sulfo group and a sulfonate group (excluding sulfuric acid and its salts), and Polishing solution with a pH greater than 4.5.
2. In claim 1, A polishing solution in which the above-mentioned abrasive particles contain cerium hydroxide.
3. In claim 1, A polishing liquid comprising an aromatic compound having at least one selected from the group consisting of a sulfo group and a sulfonate group, wherein the above acid component is an acidic compound.
4. In claim 1, A polishing solution in which the above acid component comprises a compound not having an amino group.
5. In claim 1, A polishing solution in which the above acid component comprises an aminosulfonic acid compound.
6. In claim 1, A polishing liquid comprising at least one acid component selected from the group consisting of sulfanilic acid and its salts.
7. In claim 1, A polishing liquid in which the content of the above acid component exceeds 0.2 mass% based on the total mass of the polishing liquid.
8. In claim 1, A polishing liquid containing a nonionic polymer.
9. In claim 8, A polishing liquid in which the above nonionic polymer comprises a glycerin-based polymer.
10. In claim 1, A polishing solution containing additional basic components.
11. In claim 1, A polishing liquid used for polishing a surface to be polished, comprising silicon oxide and silicon nitride.
12. A polishing method comprising a process of polishing a surface to be polished using a polishing liquid described in any one of claims 1 to 11.
13. In claim 12, A polishing method in which the above-mentioned surface to be polished comprises silicon oxide and silicon nitride.
14. A method for manufacturing a part, comprising a process of obtaining a part using a workpiece polished by the polishing method described in claim 12.

Description

Polishing liquid and polishing method The present disclosure relates to a polishing liquid, a polishing method, etc. In recent semiconductor device manufacturing processes, the importance of processing technology for high density and miniaturization is increasing. Chemical Mechanical Polishing (CMP) technology, which is one of the processing technologies, has become an essential technology in semiconductor device manufacturing processes for the formation of shallow trench isolation (hereinafter referred to as "STI"), planarization of pre-metal insulating materials or interlayer insulating materials, and the formation of plugs or buried metal wiring. As for the most widely used polishing liquids, for example, silica-based polishing liquids containing silica (silicon oxide) particles such as fumed silica or colloidal silica as abrasive particles can be cited. Silica-based polishing liquids are characterized by their high versatility, and by appropriately selecting the abrasive particle content, pH, additives, etc., a wide range of materials, regardless of whether they are insulating or conductive materials, can be polished. Meanwhile, there is also an expanding demand for polishing solutions containing cerium compound particles as abrasives, primarily intended for insulating materials such as silicon oxide. For example, a cerium oxide-based polishing solution containing cerium oxide particles as abrasives can polish silicon oxide at high speed even with a lower abrasive content than a silica-based polishing solution (see, for example, Patent Documents 1 and 2 below). Recently, in the manufacturing process of semiconductor devices, there is a demand to achieve further miniaturization of wiring, and polishing scratches occurring during polishing are becoming a problem. That is, when polishing is performed using conventional cerium oxide-based polishing liquid, even if minute polishing scratches occur, it is not a problem as long as the size of these scratches is smaller than the conventional wiring width; however, when aiming to achieve further miniaturization of wiring, even minute polishing scratches become a problem. Regarding this issue, polishing solutions using particles of cerium hydroxide are being investigated (see, for example, Patent Documents 3 to 5 below). In addition, methods for manufacturing particles of cerium hydroxide are also being investigated (see, for example, Patent Documents 6 and 7 below). Hereinafter, embodiments of the present disclosure will be described in detail. <Definition> In this specification, "polishing liquid" is defined as a composition that comes into contact with the surface to be polished during polishing. The term "polishing liquid" itself does not limit the components contained in the polishing liquid. As described below, the polishing liquid according to the present embodiment may contain abrasive grains. Abrasive grains are also referred to as "abrasive particles," but in this specification, they are referred to as "abrasive grains." Abrasive grains are generally solid particles, and while it can be assumed that the material to be removed is removed during polishing through the mechanical action of the abrasive grains and the chemical action of the abrasive grains (mainly the surface of the abrasive grains), the polishing mechanism is not limited. "Polishing rate" refers to the rate at which material is removed per unit time (removal rate). A numerical range indicated by "~" represents a range that includes the values listed before and after "~" as the minimum and maximum values, respectively. "A or greater" in a numerical range means A and a range exceeding A. "A or less" in a numerical range means A and a range less than A. In numerical ranges described stepwise in this specification, the upper or lower limit of a numerical range in a given step may be arbitrarily combined with the upper or lower limit of a numerical range in another step. In numerical ranges described in this specification, the upper or lower limit of said numerical range may be substituted with the values shown in the examples. Unless specifically stated otherwise, the materials exemplified in this specification may be used as a single type or in combination of two or more types. The amount of each component in the composition refers to the total amount of said multiple substances present in the composition, unless specifically stated otherwise, in cases where multiple substances corresponding to each component exist in the composition. "A or B" means that either A or B may be included, or both may be included. The term "membrane" includes not only the shaped structure formed on the entire surface when observed as a plan view, but also the shaped structure formed on a part thereof. The term "process" includes not only independent processes, but also processes that cannot be clearly distinguished from other processes, provided that the intended function of the process is achieved. Polishing fluid