US-12619150-B2 - Material for forming organic film, substrate for manufacturing semiconductor device, method for forming organic film, patterning process, and compound for forming organic film

US12619150B2US 12619150 B2US12619150 B2US 12619150B2US-12619150-B2

Abstract

The present invention is a material for forming an organic film, containing: (A) a compound for forming an organic film shown by the following general formula (1A); and (B) an organic solvent, where W 1 represents a tetravalent or hexavalent organic group, n1 represents an integer of 1 or 2, n2 represents 2 or 3, each R 1 independently represents any in the following formula (1B), and a hydrogen atom of a benzene ring in the formula (1A) is optionally substituted with a fluorine atom. This provides: a compound having a dioxin structure, which is cured even under film formation conditions in inert gas, and which is capable of forming an organic underlayer film having not only excellent heat resistance and properties of filling and planarizing a pattern formed on a substrate, but also favorable film formability and adhesiveness to a substrate; and an organic film material containing the compound.

Inventors

Daisuke Kori
TAKASHI SAWAMURA

Assignees

SHIN-ETSU CHEMICAL CO., LTD.

Dates

Publication Date: 20260505
Application Date: 20220119
Priority Date: 20210215

Claims (20)

1 . A material for forming an organic film, comprising: (A) a compound for forming an organic film shown by the following general formula (1C), (1D) or (1E); and (B) an organic solvent, wherein n1 represents an integer of 1 or 2, and a hydrogen atom of a benzene ring in the formula (1C), (1D) or (1E) is optionally substituted with a fluorine atom,
2 . The material for forming an organic film according to claim 1 , wherein the component (A) is a compound shown by the following formula (1F), (1G), or (1H),
3 . The material for forming an organic film according to claim 1 , wherein the component (A) satisfies 1.00≤Mw/Mn≤1.10, where Mw is a weight-average molecular weight and Mn is a number-average molecular weight measured by gel permeation chromatography in terms of polystyrene.
4 . The material for forming an organic film according to claim 1 , wherein the component (B) is a mixture of one or more kinds of organic solvent having a boiling point of lower than 180° C. and one or more kinds of organic solvent having a boiling point of 180° C. or higher.
5 . The material for forming an organic film according to claim 1 , further comprising at least one of (C) an acid generator, (D) a surfactant, (E) a crosslinking agent, and (F) a plasticizer.
6 . A substrate for manufacturing a semiconductor device, comprising an organic film on the substrate, the organic film being a cured film of the material for forming an organic film according to claim 1 .
7 . A method for forming an organic film employed in a semiconductor device manufacturing process, the method comprising: spin-coating a substrate to be processed with the material for forming an organic film according to claim 1 ; and heating the substrate to be processed coated with the material for forming an organic film under an inert gas atmosphere at a temperature of 50° C. or higher to 600° C. or lower for 10 seconds to 7200 seconds to obtain a cured film.
8 . A method for forming an organic film employed in a semiconductor device manufacturing process, the method comprising: spin-coating a substrate to be processed with the material for forming an organic film according to claim 1 ; heating the substrate to be processed coated with the material for forming an organic film in air at a temperature of 50° C. or higher to 300° C. or lower for 5 seconds to 600 seconds to form a coating film; and then performing a heat treatment under an inert gas atmosphere at a temperature of 200° C. or higher to 600° C. or lower for 10 seconds to 7200 seconds to obtain a cured film.
9 . The method for forming an organic film according to claim 7 , wherein the inert gas has an oxygen concentration of 1% or less.
10 . The method for forming an organic film according to claim 8 , wherein the inert gas has an oxygen concentration of 1% or less.
11 . The method for forming an organic film according to claim 7 , wherein the substrate to be processed has a structure or a step with a height of 30 nm or more.
12 . The method for forming an organic film according to claim 8 , wherein the substrate to be processed has a structure or a step with a height of 30 nm or more.
13 . A patterning process comprising: forming an organic film by using the material for forming an organic film according to claim 1 on a substrate to be processed; forming a silicon-containing resist middle layer film by using a silicon-containing resist middle layer film material on the organic film; forming a resist upper layer film by using a photoresist composition on the silicon-containing resist middle layer film; forming a circuit pattern in the resist upper layer film; transferring the pattern to the silicon-containing resist middle layer film by etching while using the resist upper layer film having the formed pattern as a mask; transferring the pattern to the organic film by etching while using the silicon-containing resist middle layer film having the transferred pattern as a mask; and further transferring the pattern to the substrate to be processed by etching while using the organic film having the transferred pattern as a mask.
14 . A patterning process comprising: forming an organic film by using the material for forming an organic film according to claim 1 on a substrate to be processed; forming a silicon-containing resist middle layer film by using a silicon-containing resist middle layer film material on the organic film; forming an organic antireflective coating on the silicon-containing resist middle layer film; forming a resist upper layer film by using a photoresist composition on the organic antireflective coating, so that a 4-layered film structure is constructed; forming a circuit pattern in the resist upper layer film; transferring the pattern to the organic antireflective coating and the silicon-containing resist middle layer film by etching while using the resist upper layer film having the formed pattern as a mask; transferring the pattern to the organic film by etching while using the silicon-containing resist middle layer film having the transferred pattern as a mask; and further transferring the pattern to the substrate to be processed by etching while using the organic film having the transferred pattern as a mask.
15 . A patterning process comprising: forming an organic film by using the material for forming an organic film according to claim 1 on a substrate to be processed; forming an inorganic hard mask selected from a silicon oxide film, a silicon nitride film, a silicon oxynitride film, a titanium oxide film, and a titanium nitride film on the organic film; forming a resist upper layer film by using a photoresist composition on the inorganic hard mask; forming a circuit pattern in the resist upper layer film; transferring the pattern to the inorganic hard mask by etching while using the resist upper layer film having the formed pattern as a mask; transferring the pattern to the organic film by etching while using the inorganic hard mask having the transferred pattern as a mask; and further transferring the pattern to the substrate to be processed by etching while using the organic film having the transferred pattern as a mask.
16 . A patterning process comprising: forming an organic film by using the material for forming an organic film according to claim 1 on a substrate to be processed; forming an inorganic hard mask selected from a silicon oxide film, a silicon nitride film, a silicon oxynitride film, a titanium oxide film, and a titanium nitride film on the organic film; forming an organic antireflective coating on the inorganic hard mask; forming a resist upper layer film by using a photoresist composition on the organic antireflective coating, so that a 4-layered film structure is constructed; forming a circuit pattern in the resist upper layer film; transferring the pattern to the organic antireflective coating and the inorganic hard mask by etching while using the resist upper layer film having the formed pattern as a mask; transferring the pattern to the organic film by etching while using the inorganic hard mask having the transferred pattern as a mask; and further transferring the pattern to the substrate to be processed by etching while using the organic film having the transferred pattern as a mask.
17 . The patterning process according to claim 16 , wherein the inorganic hard mask is formed by a CVD method or an ALD method.
18 . The patterning process according to claim 16 , wherein the circuit pattern is formed by a lithography using light with a wavelength of 10 nm or more to 300 nm or less, a direct drawing with electron beam, nanoimprinting, or a combination thereof.
19 . The patterning process according to claim 16 , wherein when the circuit pattern is formed, the circuit pattern is developed by alkali development or with an organic solvent.
20 . The patterning process according to claim 16 , wherein the substrate to be processed is a semiconductor device substrate or the semiconductor device substrate coated with any of a metal film, a metal carbide film, a metal oxide film, a metal nitride film, a metal oxycarbide film, and a metal oxynitride film.

Description

TECHNICAL FIELD The present invention relates to: a material for forming an organic film used in a semiconductor device manufacturing process; a substrate for manufacturing a semiconductor device by using the material; a method for forming an organic film using the material; a patterning process according to a multilayer resist method using the material; and a compound for forming an organic film suitably used in the material. BACKGROUND ART Conventionally, high integration and high processing speed of semiconductor devices have been achieved through the miniaturization of pattern size by shortening the wavelength of light sources in lithography technology using light exposure (photolithography), which is commonly employed technology. To form such a fine circuit pattern on a substrate for a semiconductor device (substrate to be processed), the following method is generally employed in which the substrate to be processed is processed by dry-etching while using a patterned photoresist film as an etching mask. In practice, however, there is no dry-etching method capable of providing an absolute etching selectivity between the photoresist film and the substrate to be processed. Hence, recently, it has been common to process a substrate by a multilayer resist method. This method is as follows: first, an underlayer film having an etching selectivity different from that of a photoresist film (hereinafter, resist upper layer film) is placed between the resist upper layer film and a substrate to be processed; a pattern is formed in the resist upper layer film; then, the pattern is transferred to the underlayer film by dry-etching while using the resist upper layer film pattern as a dry-etching mask; furthermore, the pattern is transferred to the substrate to be processed by dry-etching while using the underlayer film as a dry-etching mask. One of the multilayer resist methods is a 3-layer resist method which can be performed with a typical resist composition used in a monolayer resist method. In this three-layer resist method, a substrate to be processed is coated with an organic underlayer film material composed of an organic resin-containing composition and then baked to form an organic underlayer film (hereinafter, organic film); the organic film is subsequently coated with a resist middle layer film material composed of a composition containing a silicon-containing resin, and baked to form a silicon-containing film (hereinafter, silicon-containing resist middle layer film); thereafter, a typical organic photoresist film (hereinafter, resist upper layer film) is formed on the silicon-containing resist middle layer film. The resist upper layer film is patterned and then subjected to dry-etching with fluorine-based gas plasma, so that the resist upper layer film pattern can be transferred to the silicon-containing resist middle layer film. This is because the organic resist upper layer film can exhibit a favorable etching selectivity ratio relative to the silicon-containing resist middle layer film. This method allows a pattern to be easily transferred to the silicon-containing resist middle layer film even if the resist upper layer film does not have sufficient film thickness for directly processing the substrate to be processed or if the resist upper layer film does not have sufficient dry-etching resistance for processing the substrate to be processed. This is because the silicon-containing resist middle layer film generally has a film thickness equal to or smaller than that of the resist upper layer film. Subsequently, while using the silicon-containing resist middle layer film having the transferred pattern as a dry-etching mask, the pattern is transferred to the organic film by dry-etching with oxygen- or hydrogen-based gas plasma. Thereby, the pattern can be transferred to the organic film having dry-etching resistance sufficient for substrate processing. This organic film pattern having the transferred pattern can be transferred to the substrate by dry-etching with a fluorine-based gas, chlorine-based gas, or the like. Meanwhile, the miniaturization in the semiconductor device manufacturing process is approaching the limit inherent in the wavelength of light sources for photolithography. Accordingly, recently, the high integration of semiconductor devices that does not rely on miniaturization has been examined. As one means for the high integration, semiconductor devices having complicated structures such as multigate structures have been examined, and some of these have already been put into practical use. In forming such structures by multilayer resist methods, it is possible to employ an organic film material which is capable of filling a fine pattern including hole, trench, and fin formed on a substrate to be processed with a film without void, and capable of filling a step- or pattern-dense region and a pattern-free region with a film to planarize the regions. The use of such an organic film material t