KR20090070142A - Gap-fill composition and method of forming interconnection line for semiconductor device - Google Patents

Abstract

A gap-fill composition is provided to be charged without voids even when filling a via hole or a trench hole having big aspect ratio, and to ensure dry etch rate identical a low-K dielectric interlayer insulating film or high wet etch selectivity. A gap-fill composition comprises a compound selected from the group consisting of an aromatic ring-containing compound represented by chemical formula 1 or chemical formula 2, which has average molecular weight(Mw) of 1,000-20,000; and an organic solvent. In chemical formula 1, n is <= n <= 190; R1 and R2 are independently any one selected from chemical formulae 3-5; R3 is represented by chemical formula 6; and R4 and R5 are independently hydrogen or alkyl. In chemical formula 2, n is <= n <= 190; R6 is any one selected from chemical formulae 3-5; R7 is represented by chemical formula 6; and R8-R11 are independently hydrogen or alkyl.

Description

GAP-FILL COMPOSITION AND METHOD OF FORMING INTERCONNECTION LINE FOR SEMICONDUCTOR DEVICE}

The present invention relates to a gap-fill composition and a wiring forming method of a semiconductor device using the same, and more particularly, via holes in forming a multilayer wiring structure using a dual damascene process. The present invention relates to a gap-fill composition filling a hole and a trench hole, and a wiring forming method of a semiconductor device using the same.

As the integration of semiconductor devices is increasingly required, copper (Cu) wiring process is adopted instead of the conventional aluminum (Al) wiring to improve the characteristics such as the operation speed and resistance of the device. Dual damascene processing methods using low-k materials are being used.

A brief description of the dual damascene process is as follows. First, a first low dielectric film, a first etch stop film, a second low dielectric film, and a second etch stop film are sequentially formed on a lower layer on which a lower metal wiring is formed. A via hole is then formed through the photoresist mask to the first low dielectric layer, and the via hole is filled with a gap-fill composition. The gap-fill cured film formed by thermosetting the gap-fill composition is etched and removed leaving only a portion at the bottom of the via hole. A trench hole is formed in the second low dielectric layer using a photoresist mask for forming a trench hole on the first etch stop layer, and the gap-fill cured film remaining at the bottom of the via hole is removed. Subsequently, metal wiring, such as Cu, is embedded in the formed via hole and trench hole.

When the trench hole is formed by etching after the via hole is formed in the dual damascene process, if the substrate surface is exposed at the bottom of the via hole, the surface of the lower layer may be damaged by the etching material, Can cause problems. In order to solve this problem, a part of the gap-fill cured film is left at the bottom of the via hole as a protective film, and then a subsequent process is performed.

Since the aspect ratios of the via holes and trench holes formed by the dual damascene process may be as high as 4 to 5 or more, the gap-fill composition should be a material that can be easily buried above the aspect ratio above. However, if the conventional gap-fill composition is to be filled in a hole having an aspect ratio of 4 to 5, bubbles are not generated to serve as a protective film, and the thickness required for the bottom of the via hole after etching the gap-fill cured film is required. You cannot leave a shield to have.

In order to solve this problem, efforts have been made to control the amount of the photosensitive component having high light absorbing ability in the photoresist composition. However, when the amount of the photosensitive component is increased, the transmission of light to be exposed is poor, resulting in poor resolution. On the contrary, when the amount of the photosensitive component is reduced, a problem arises in that the whole of the light to be exposed is exposed to leave a protective film of a required thickness.

In order to overcome the above-mentioned problems of the prior art, an object of the present invention is to provide a gap-fill composition having excellent gap-fill performance for filling via holes and trench holes having an aspect ratio of 4 to 5 or more.

The present invention also aims to provide a gap-fill composition in which a gap-fill cured film remaining on the bottom of a hole after etching the gap-fill cured film formed by curing the gap-fill composition can serve as a protective film at the bottom of the hole. do.

The present invention also exhibits a gap-fill cured film which exhibits a dry etch rate substantially the same as that of the low dielectric interlayer insulating film in the dry etching process, and which has a very large etching selectivity compared to the low dielectric film in the wet etching process. It is intended to provide a composition.

Another object of the present invention is to provide a method for forming a wiring of a semiconductor device using the gap-fill composition.

However, technical problems to be achieved by the present invention are not limited to the above-mentioned problems, and other technical problems will be clearly understood by those skilled in the art from the following description.

Other specific details of embodiments of the present invention are included in the following detailed description.

The gap-fill composition of the present invention is easily filled in via holes and trench holes having an aspect ratio of 4 to 5 or more, and exhibits a dry etching rate that is substantially the same as that of a low dielectric interlayer insulating film, depending on etching methods and conditions. It can have a large wet etch selectivity. In addition, it is possible to provide a gap-fill cured film that can serve as a protective film after exposure and development, thereby forming the wiring of the semiconductor device without damaging the lower wiring layer. The gap-fill composition of the present invention can be usefully used in the manufacture of semiconductor integrated circuit devices.

Hereinafter, embodiments of the present invention will be described in detail. However, this is presented as an example, by which the present invention is not limited and the present invention is defined only by the scope of the claims to be described later.

The gap-fill composition according to one embodiment of the present invention has a weight average molecular weight (Mw) of 1,000 to 20,000, a compound selected from the group consisting of aromatic ring-containing compounds and combinations thereof represented by the following general formula (1) or (2) ; And organic solvents.

[Formula 1]

Wherein n is in the range of 1 ≦ n ≦ 190,

R ₁ and R ₂ are each independently any one of the following Formulas 3 to 5,

R ₃ is represented by the following formula (6),

R ₄ and R ₅ are each independently hydrogen or alkyl.

[Formula 2]

Wherein n is in the range of 1 ≦ n ≦ 190,

R ₆ is any one of the following Formulas 3 to 5,

R ₇ is represented by the following formula (6),

R ₈ to R ₁₁ are each independently hydrogen or alkyl.

[Formula 3]

In Formula 3, R _a and R _b are each independently hydrogen, substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl , Hydroxy, substituted or unsubstituted C1 to C10 alkoxy, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C30 heteroaryl, And substituted or unsubstituted C1 to C20 heterocycloalkyl,

At least one of R _a and R _b is hydroxy, alkoxy, substituted alkoxy,

l and m are each 0 to 4 and the sum of 1 and m is 4 or less.

[Formula 4]

In Formula 4, R _a to R _d are each independently hydrogen, substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl , Hydroxy, substituted or unsubstituted C1 to C10 alkoxy, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C30 heteroaryl, And substituted or unsubstituted C1 to C20 heterocycloalkyl,

At least one of R _a to R _d is at least one of hydroxy, alkoxy, substituted alkoxy,

l, m, p and q are each 0-4 and 1 + m + p + q is 6 or less.

[Formula 5]

In Formula 5, R _a to R _f are each independently hydrogen, substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl , Hydroxy, substituted or unsubstituted C1 to C10 alkoxy, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C30 heteroaryl, And substituted or unsubstituted C1 to C20 heterocycloalkyl,

At least one of R _a to R _f is at least one of hydroxy, alkoxy, or substituted alkoxy,

l, m, p and q are each 0-4 and 1 + m + p + q is 6 or less.

[Formula 6]

In Formula 6, R _g and R _j are each independently substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl, hydride Hydroxy, substituted or unsubstituted C1 to C10 alkoxy, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C30 heteroaryl, and substitution Or unsubstituted C1 to C20 heterocycloalkyl,

Ar is a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C2 to C60 heteroaryl group, a substituted or unsubstituted C7 to C30 arylalkyl group and a substituted or unsubstituted C4 to C30 heteroaryl May be selected from the group consisting of alkyl groups,

r is an integer from 0 to 2,

k is an integer of 1-2.

In another embodiment, a method of forming a wiring of a semiconductor device may include: (a) forming a first insulating layer on a lower layer by a lower wiring; (b) selectively removing the first insulating film to form a via hole for opening the lower metal wiring; (c) filling the via hole with the gap-fill composition and then thermosetting to form a gap-fill cured film; (d) forming a second insulating film on the first insulating film; (e) selectively removing the second insulating film to form trench holes for opening the gap-fill cured film; (f) removing the gap-fill cured film; (g) filling the via hole and the trench hole with a conductive material to form an upper wiring.

In another embodiment, a method of forming a wiring of a semiconductor device may include: (a) forming a first insulating film, a first etch stop film, a second insulating film, and a second etch stop film on the semiconductor substrate; (b) forming a resist mask having a pattern for forming a via hole on the second etch stop layer; (c) forming a via hole through the resist mask to a first insulating film; (d) embedding the gap-fill composition in the via hole and thermally curing to form a gap-fill cured film; (e) etching and removing the gap-fill cured film leaving a part of the bottom of the via hole; (f) forming a resist mask having a pattern for forming a trench hole in the second etch stop layer; (g) forming a trench hole in the second insulating film through the resist mask, and simultaneously removing the gap-fill composition remaining in the bottom of the via hole; (h) embedding a conductive material in the trench holes and via holes to form an upper wiring.

Other specific details of embodiments of the present invention are included in the following detailed description.

 Hereinafter, embodiments of the present invention will be described in detail. However, this is presented as an example, by which the present invention is not limited and the present invention is defined only by the scope of the claims to be described later.

According to one embodiment of the present invention, a group consisting of an aromatic ring-containing compound represented by the following formula (1) or (2) and a combination thereof for filling a via hole or a trench hole of a multilayer wiring structure to form a gap-fill cured film A compound selected from; And an organic solvent.

[Formula 1]

Wherein n is in the range of 1 ≦ n ≦ 190,

R ₁ and R ₂ are each independently any one of the following Formulas 3 to 5,

R ₃ is represented by the following formula (6),

R ₄ and R ₅ are each independently hydrogen or alkyl.

[Formula 2]

Wherein n is in the range of 1 ≦ n ≦ 190,

R ₆ is any one of the following Formulas 3 to 5,

R ₇ is represented by the following formula (6),

R ₈ to R ₁₁ are each independently hydrogen or alkyl.

[Formula 3]

In Formula 3, Ra and Rb are each independently hydrogen, substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl, hydride Hydroxy, substituted or unsubstituted C1 to C10 alkoxy, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C30 heteroaryl, and substitution Or unsubstituted C1 to C20 heterocycloalkyl,

At least one of Ra and Rb is hydroxy, alkoxy, or substituted alkoxy,

l and m are each 0 to 4 and the sum of 1 and m is 4 or less.

[Formula 4]

In Formula 4, Ra to Rd are each independently hydrogen, substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl, hydride Hydroxy, substituted or unsubstituted C1 to C10 alkoxy, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C30 heteroaryl, and substitution Or unsubstituted C1 to C20 heterocycloalkyl,

At least one of Ra to Rd is hydroxy, alkoxy, or substituted alkoxy,

l, m, p and q are each 0-4 and 1 + m + p + q is 6 or less.

[Formula 5]

In Formula 5, Ra to Rf are each independently hydrogen, substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl, hydride Hydroxy, substituted or unsubstituted C1 to C10 alkoxy, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C30 heteroaryl, and substitution Or unsubstituted C1 to C20 heterocycloalkyl,

At least one of Ra to Rf is hydroxy, alkoxy, or substituted alkoxy,

l, m, p and q are each 0-4 and 1 + m + p + q is 6 or less.

[Formula 6]

In Formula 6, Rg and Rj are each independently substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl, hydroxy, Substituted or unsubstituted C1 to C10 alkoxy, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C30 heteroaryl, and substituted or unsubstituted It is selected from the group consisting of substituted C1 to C20 heterocycloalkyl,

Ar is a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C2 to C30 heteroaryl group, a substituted or unsubstituted C7 to C30 arylalkyl group, and a substituted or unsubstituted C4 to C30 hetero May be selected from the group consisting of arylalkyl groups,

r is an integer from 0 to 2,

k is an integer of 1-2.

Specific examples of Chemical Formulas 3 to 5 may include the following Chemical Formulas a to e.

[Formula a] [Formula b]

[Formula c] [Formula d]

[Formula e]

Specific examples of Chemical Formula 6 include the following Chemical Formulas g to m.

[Formula g] [Formula h]

[Formula i] [Formula j]

[Formula k] [Formula l]

[Formula m]

[Formula n]

Unless stated otherwise in the present specification, "alkyl" means alkyl of C1 to C10, "alkenyl" means alkenyl of C2 to C10, "alkynyl" means alkynyl of C2 to C10, and "alkoxy" means C1 to C10 alkoxy, "aryl" means C6 to C30 aryl, "heteroaryl" means C2 to C30 heteroaryl containing 1 to 7 hetero atoms selected from the group consisting of N, O, S and P, “Arylalkyl” means C7 to C30 arylalkyl, “Heteroarylalkyl” means C4 to C30 heteroarylalkyl containing 1 to 7 hetero atoms selected from the group consisting of N, O, S and P, “ Cycloalkyl "means C3 to C20 cycloalkyl, and" heterocycloalkyl "means C1 to C20 heterocycloalkyl containing 1 to 7 hetero atoms selected from the group consisting of N, O, S and P. .

In the present specification, "substituted" means that the hydrogen atom in the compound is a halogen atom (F, Br, Cl, or I), hydroxy group, alkoxy group, nitro group, cyano group, amino group, azido group, amidino group, hydrazino group , Hydrazono group, carbonyl group, carbamyl group, thiol group, ester group, carboxyl group or salt thereof, sulfonic acid group or salt thereof, phosphoric acid or salt thereof, alkyl group of C1 to C10, alkenyl group of C2 to C10, alky of C2 to C10 It is substituted with one or more substituents selected from the group consisting of a silyl group, a C6 to C30 aryl group of C1 to C10, an arylalkyl group of C7 to C30, a heteroarylalkyl group of C4 to C30, and a cycloalkyl group of C3 to C20 do.

The aromatic ring-containing compound of Formula 1 or Formula 2 or a mixture thereof is dissolved in an organic solvent as a heat crosslinkable compound to form a gap-fill composition.

The compound of Formula 1 or Formula 2 includes an aromatic ring having strong absorption in a short wavelength region. In addition, when these compounds of Formula 1 or 2 polymerize to form a polymer, respectively (when n is 2 or more in Formulas 1 and 2, respectively), the aromatic ring is preferably present in the skeleton portion of the polymer. Polymers of aromatic rings located in the backbone can improve etch characteristics.

In addition, the aromatic ring-containing compound preferably contains a substantial amount of a group capable of crosslinking reaction, the crosslinking reaction between the polymers can proceed by this group. In addition, the crosslinking reaction of the polymer and the crosslinking agent may further proceed if the crosslinking agent is further described. In addition, the aromatic ring-containing compound must have a film-forming property and a property of dissolving in an organic solvent which helps to form a gap-fill cured film by conventional spin-coating.

The aromatic ring-containing compound of the present invention preferably has a weight average molecular weight (Mw) of about 1,000 to 20,000 and more preferably has a weight average molecular weight of about 1000 to 10,000. When the molecular weight is in the range of 1000 to 10,000, the filling property to be filled in the hole pattern is particularly good.

The aromatic ring-containing compound is preferably used in 1 to 30 parts by weight based on 100 parts by weight of the organic solvent. When the aromatic ring-containing polymer is used in an amount of less than 1 part by weight or in excess of 30 parts by weight, it is difficult to achieve an accurate coating thickness because it becomes less than or exceeds the desired coating thickness.

According to another embodiment of the present invention, the aromatic ring-containing compound may be used in an amount of 1 to 20% by weight, more preferably in an amount of 2 to 15% by weight, even more preferably 3 To 10% by weight. Within this range, desirable coating properties of the gap-fill composition can be obtained.

The organic solvent is not particularly limited as long as it is an organic solvent having sufficient solubility in the aromatic ring-containing compound, and for example, solvents such as carboxylate, ether and ketone may be used. More specifically, alkylene glycol monoalkyl ether acetates such as propylene glycol monomethyl ether acetate (PGMEA), alkylene glycol monoalkyl ethers such as propylene glycol monomethyl ether (PGME), cyclohexanone (Anone), ethyl lactate (EL) etc. are mentioned. Alkyl and alkylene in the organic solvent are preferably C1 to C20 alkyl and alkylene.

The content of the organic solvent is not particularly limited, but it is preferable to use 75 to 99 parts by weight based on 100 parts by weight of the composition in order to provide a smooth coating property.

The gap-fill composition may further include at least one component selected from the group consisting of a catalyst capable of promoting a crosslinking reaction, a crosslinking agent capable of enhancing a degree of crosslinking, and an additive.

As the catalyst, an acid catalyst or a base catalyst may be used. As the acid catalyst, p - toluenesulfonic acid monohydrate can be used, such as organic acids (p -toluenesulfonic acid mono hydrate), can also be used a compound of the grid (Thermal Acid Generater) a plan TAG storage stability as a catalyst. TAG, for example as an acid generator compound which is adapted to discharge the heat treatment acid pyridinium p - toluenesulfonate (Pyridinium p -toluene sulfonate), 2,4,4,6- tetrabromo-necked claw-hexadiene-one, Compounds selected from the group consisting of benzoin tosylate, 2-nitrobenzyl tosylate, alkyl esters of organic sulfonic acids, wherein alkyl is C1 to C20 alkyl, and combinations thereof, may be preferably used. As the base catalyst, an imidazole compound such as 2-methylimidazole may be used.

The catalyst may be used in an amount of 0.001 to 0.05 parts by weight, preferably 0.001 to 0.03 parts by weight, based on 100 parts by weight of the composition. If the catalyst is less than 0.001 parts by weight, the desired crosslinking properties may not appear. If the catalyst is more than 0.05 parts by weight, it may affect the storage stability due to excessive input.

The crosslinking agent is preferably a crosslinking agent which can be reacted with a hydroxy group or an alkoxy group of an aromatic ring containing compound in a manner that can be catalyzed by an added catalyst. The crosslinking agent includes an etherified amino resin; Alkylated melamine resins ( N -methoxymethyl-melamine resins or N -butoxymethyl-melamine resins); Etherified amino resins, alkylated, for example methylated or butylated Urea Resin (Cymel U-65 Resin or UFR 80 Resin); Alkylated, for example methylated / butylated glycolurils (Glycouryl; Powderlink 1174), such as structures of Formula 7; The compounds described in Canadian Patent No. 1 204 547; Compounds having methylated / butylated glycoluril of formula 7, including 2,6-bis (hydroxymethyl) -p -cresol compound; The compound of Unexamined-Japanese-Patent No. 1-293339 is included. The amino resins and glycolurils described above are available from Cytec Industries. Bisepoxy compounds can also be used as crosslinking agents.

This includes. The amino resins and glycolurils described above are available from Cytec Industries. Bisepoxy compounds can also be used as crosslinking agents.

[Formula 7]

The crosslinking agent may be used in an amount of 0.05 to 5 parts by weight, preferably 0.1 to 3 parts by weight, based on 100 parts by weight of the composition. If the crosslinking agent is less than 0.05 parts by weight, the crosslinking properties may not appear. If the crosslinking agent exceeds 5 parts by weight, excessive deformation may cause deformation of the pattern profile and contamination of the redeposition due to volatile generation during the baking process.

The gap-fill composition of the present invention may additionally contain additives such as surfactants.

On the other hand, according to another embodiment of the present invention provides a method for forming a wiring using the gap-fill composition. In order to form wires according to the dual dimasine process, the gap-fill cured film formed of the gap-fill composition may have substantially the same dry etching rate as the interlayer insulating film, or the dry etching ratio of the gap-fill cured film: interlayer insulating film may be 4: 1 or less. It must be a substance. In addition, it should be a material having a very fast wet etching rate in the subsequent wet etching process compared to the interlayer insulating film. Preferably, the wet-etch ratio of the gap-fill cured film: interlayer insulating film is a material having a characteristic of 20: 1 or more.

In another embodiment, a method of forming a wiring of a semiconductor device includes: (a) forming a first insulating layer on a lower layer by a lower wiring; (b) selectively removing the first insulating film to form a via hole for opening the lower metal wiring; (c) filling the via hole with the gap-fill composition and then thermosetting to form a gap-fill cured film; (d) forming a second insulating film on the first insulating film; (e) selectively removing the second insulating film to form trench holes for opening the gap-fill cured film; Removing the gap-fill cured film; (f) filling the via hole and the trench hole with a conductive material to form an upper wiring.

In another embodiment, a method of forming a wiring of a semiconductor device may include: (a) forming a first insulating film, a first etch stop film, a second insulating film, and a second etch stop film on the semiconductor substrate; (b) forming a resist mask having a pattern for forming a via hole on the second etch stop layer; (c) forming a via hole through the resist mask to a first insulating film; (d) embedding the gap-fill composition in the via hole and thermally curing to form a gap-fill cured film; (e) etching and removing the gap-fill cured film leaving a part of the bottom of the via hole; (f) forming a resist mask having a pattern for forming a trench hole in the second etch stop layer; (g) forming a trench hole in the second insulating film through the resist mask, and simultaneously removing the gap-fill composition remaining in the bottom of the via hole; (h) embedding conductive material in the trench holes and via holes to form an upper wiring.

A method of forming a wiring of a semiconductor device using the gap-fill composition will be described with reference to FIG. 1. 1 is a cross-sectional view for each process illustrating a process for forming a dual damascene pattern of a semiconductor device. Referring to FIG. 1, first, a low-temperature oxide film is deposited on a lower layer 1 on which lower wirings are formed to form a first insulating film 3. Next, the first photoresist layer pattern 10 having a predetermined shape is formed on the first insulation layer 3 through a photolithography process to form the via hole 20 penetrating through the first insulation layer 3. To form. Subsequently, the first insulating layer 3 is selectively removed by etching using the first photoresist layer pattern 10 as a mask. Thus, a via hole 10 is formed through the first insulating film 3 that has been selectively removed to open the lower wiring. Next, in order to fill the via hole 20 with the gap-fill composition, first, the first photoresist layer pattern 10 is removed, and the gap-fill composition 30 is sufficiently thick on the entire surface of the first insulating layer 3. Apply with At this time, the thickness of the gap-fill composition 30 may be formed by a spin-coating method so as to be 500 kPa or more in the patternless region, the temperature of 80 to 400 ℃, preferably 80 to 300 so that heat curing occurs The gap-fill cured film 32 may be formed by heating to a temperature of 占 폚. Thereafter, the gap-fill cured film 32 is partially removed by a chemical mechanical polishing (CMP) process or an etchback process so that the first insulating film 3 is exposed. Therefore, the gap-fill cured film 32 exists only in the via hole 20.

 Thereafter, a low temperature oxide film is deposited on the first insulating film 3 to form a second insulating film 7. A second photosensitive film pattern 12 having a predetermined shape is formed on the second insulating film 7 through a photolithography process for forming a trench hole penetrating the second insulating film 7. Next, the second insulating layer 7 is selectively removed by etching using the second photosensitive layer pattern 12 as a mask. A trench hole 22 for opening the gap-fill cured film 32 is formed in the second insulating film 7 that is selectively removed.

The gap-fill cured film 32 filling the via hole may serve as an etch barrier to protect the via hole sidewall and the lower wiring. That is, the via hole sidewalls and the lower wiring are not damaged.

Thereafter, the gap-fill cured film 32 is removed to form a dual damascene pattern including the via hole 20 and the trench hole 22. The via hole 20 and the trench hole 22 are filled with a conductive material 26 such as a metal, for example, copper, aluminum, or tungsten, to form an upper wiring.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the following Examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

Synthesis Example 1

(Synthesis of 9,9-bishydroxyphenylfluorene and 1,4-bismethoxymethylbenzene copolymer)

A 3 L four-necked flask equipped with a mechanical stirrer, cooling tube, 350.41 g (1.0 mol) of 9,9-bishydroxyphenyl fluorene, 3.08 g (0.02 mol) of diethyl sulfate and propylene glycol mono 350 g of methyl ether was added thereto, followed by stirring while maintaining the temperature of the reactor at 115 ° C. After 10 minutes, 166.22 g (1 mol) of 1,4-bismethoxymethylbenzene was added dropwise, and the reaction was carried out at the same temperature for 15 hours. To complete the reaction, 2.98 g (0.02 mol) of triethanolamine was added as a neutralizing agent. After completion of the reaction, the acid was removed using a water / methanol mixture, and then, a low molecular weight containing oligomer and monomer was removed using methanol to obtain a polymer represented by Formula 8 (Mw = 10,000, polydispersity = 2.0). , n = 17).

[Formula 8]

Synthesis Example 2

(Synthesis of 9,9-bishydroxyphenylfluorene and 4,4'-bismethoxymethyl-bisphenyl copolymer)

      The same procedure as in Synthesis Example 1 was repeated except that 242.31 g of 1 mol of 4,4'-bismethoxymethyl-bisphenyl was added to the reactor instead of 166.22 g of 1,4-bismethoxymethylbenzene. The polymer represented by 9 was synthesized.

     The molecular weight and the dispersion degree of the obtained copolymer were measured by GPC under tetrahydrofuran to obtain a polymer having a weight average molecular weight (Mw) of 11,000 and a dispersion degree of 2.0 (n = 16).

[Formula 9]

Synthesis Example 3

(Synthesis of 1-naphthol and 9,10-bismethoxymethylanthracene copolymer)

      1 mol of 144.17 g of 1-naphthol was added to the reactor in place of 350.41 g of 9,9-bishydroxyphenylfluorene, 1 mol of 9,10-bismethoxymethylanthracene 266.33 g of 1,4-bismethoxy A polymer represented by the following Chemical Formula 10 was synthesized in the same manner as in Synthesis Example 1, except that 166.22 g of methylbenzene was added to the reactor.

     The molecular weight and the dispersion degree of the obtained copolymer were measured by GPC under tetrahydrofuran to obtain a weight average molecular weight (Mw) of 10,000 and a polymer of dispersion degree 2.1 (n = 14).

[Formula 10]

In Formula 10, the molar ratio of m / n is 40:60.

Synthesis Example 4

(Synthesis of Fluorenylidenediphenol and 1,4-bismethoxymethylbenzene copolymer)

The same procedure as in Synthesis Example 1 was repeated except that 393.50 g of 1 mol of fluorenylidenediphenol was added to the reactor instead of 445.58 g of 1 mol of 4,4 '-(9-fluorenylidene) divinylphenol. The polymer represented by 11 was synthesized.

The weight average molecular weight and dispersion degree of the obtained copolymer were measured by GPC under tetrahydrofuran, and the polymer (n = 17) of the weight average molecular weight 10,000 and dispersion degree 1.9 was obtained.

[Formula 11]

[Examples 1-3]

0.8 g of each of the polymers prepared in Synthesis Examples 1 to 3 was weighed, and 2 mg of 2-methylimidazole was dissolved in 9 g of propylene glycol monomethylether acetate (hereinafter referred to as PGMEA), followed by filtration. Sample solutions of Examples 1 to 3 were prepared.

[Examples 4 to 7]

To respectively by weighing 0.8 g of a polymer produced in Synthesis Example 1-4 crosslinking agent of formula 7 (Powderlink 1174) 0.2 g, pyridinium p - toluenesulfonate (Pyridinium p -toluene sulfonate) 2 mg of propylene glycol monomethyl ether acetate (Propylene glycol monomethylether acetate, hereinafter referred to as PGMEA) was dissolved in 9 g and filtered to prepare sample solutions of Examples 4 to 7, respectively.

[Formula 7]

Example 8

Each of the sample solutions prepared in Examples 1 to 7 was coated on a silicon wafer by spin-coating, and then heat-treated at 240 ° C. for 60 seconds to obtain a cured film.

The refractive index (n) and extinction coefficient (k) of the cured films formed at this time were obtained, respectively. The instrument used was Ellipsometer (J. A. Woollam) and the measurement results are shown in Table 1.

Table 1

Samples Used to Prepare Cured Films Optical properties (193nm) Optical properties (248nm) n (refractive index) k (absorption coefficient) n (refractive index) k (absorption coefficient) Example 1 1.47 0.68 1.91 0.21 Example 2 1.43 0.31 2.12 0.30 Example 3 1.21 0.35 2.11 0.64 Example 4 1.46 0.65 1.90 0.20 Example 5 1.42 0.30 2.10 0.30 Example 6 1.20 0.34 2.10 0.63 Example 7 1.44 0.63 1.90 0.20 Comparative Example 1

As shown in Table 1, it was confirmed that there are refractive indices and absorbances usable as gap-fill cured films at ArF (193 nm) and KrF (248 nm) wavelengths. However, the 248 nm extinction coefficients of Examples 3 and 6 were very It was confirmed that the level is low. From this it can be seen that the etching selectivity of the cured film formed from the gap-fill composition according to the present invention is very high.

Example 9

The sample solutions prepared in Examples 1 to 7 were each coated by spin-coating on silicon nitride-coated silicon wafers and baked at 200 ° C. for 60 seconds to form a cured film having a thickness of 4000 mm 3.

Silicone ARC was coated with 1100 mm 3 on each cured film formed and baked at 240 ° C. for 60 seconds. After coating the ArF PR on the silicon ARC 1700 700 and baked for 60 seconds at 110 ℃ and then exposed to each using an exposure equipment of ASML (XT: 1400, NA 0.93) and then developed with TMAH (2.38wt% aqueous solution). And using a FE-SEM to examine the line and space pattern of 63 nm, respectively, the results are shown in Table 2 below. The exposure latitude (EL) margin according to the change of the exposure amount and the depth of focus (DoF) margin according to the distance change with the light source are considered and recorded in Table 2.

TABLE 2

Pattern EL margin (mJ / exposure energy mJ) DoF margin (μm) Profile Example 1 4 0.25 cubic Example 2 4 0.25 cubic Example 3 4 0.25 cubic Example 4 4 0.25 cubic Example 5 4 0.25 cubic Example 6 4 0.25 cubic Example 7 4 0.25 cubic

From the results of Table 2, the cured film prepared with the sample solution of Examples 1 to 7 has sufficient resistance to multiple etching, so that the etch profile of the cured film that can form the protective film of the lower layer is very good, and the resist and the back layer It is possible to minimize the reflectivity of the liver, thereby showing that it is excellent in the pattern profile and margin.

Example 10

The specimens patterned in Examples 1 to 7, respectively, were subjected to dry etching of silicon ARC using PR as a mask with CHF ₃ / CF ₄ mixed gas, and then a cured film was prepared using silicon ARC as a mask with O ₂ / N ₂ mixed gas. Dry etching was performed again. Thereafter, after dry etching of silicon nitride was performed using a cured film as a mask with CHF ₃ / CF ₄ mixed gas, an O ₂ ashing and a wet strip process were performed on the remaining cured film and organic material.

Immediately after the cured film etching and the silicon nitride etching, the cross sections were examined by FE-SEM for each specimen and the results are shown in Table 3.

TABLE 3

Samples Used to Prepare Cured Films Pattern shape after cured film etching Pattern after etching silicon nitride Example 1 Anisotropic Anisotropic Example 2 Anisotropic Anisotropic Example 3 Anisotropic Anisotropic Example 4 Anisotropic Anisotropic Example 5 Anisotropic Anisotropic Example 6 Anisotropic Anisotropic Example 7 Anisotropic Anisotropic

From the results in Table 3, the pattern shape after the cured film etching and after the silicon nitride etching was good in each case, and it was judged that the etching of the silicon nitride was satisfactorily performed due to sufficient resistance by the etching gas of the cured film.

Comparative Example 1

(Synthesis of 9,9-bishydroxyphenylfluorene and 1,4-bismethoxymethylbenzene copolymer (2))

350.41 g (1.0 mol) of 9,9-bishydroxyphenylfluorene, 3.08 g (0.02 mol) of diethyl sulfate and 350 g of propylene glycol monomethyl ether were added to the reactor, and the same procedure as in Synthesis Example 1 was performed. A polymer represented by the formula (9) was synthesized.

     The weight average molecular weight and dispersion degree of the obtained copolymer were measured by GPC under tetrahydrofuran, and the polymer (n = 20) of the weight average molecular weight 25,000 and dispersion degree 2.2 was obtained.

Comparative Example 1

A sample solution was prepared in the same manner as in Examples 1 to 3 except that the polymer prepared in Comparative Synthesis Example 1 was used.

Boyd Occurrence  evaluation

The sample solutions prepared in Examples 1 to 7 and Comparative Example 1 were coated on silicon wafers each having a pattern formed of silicon oxide. The silicon wafer on which the pattern was formed was prepared as follows. First, a Plasma Enhanced TetraEthylOrthoSilicate (PE-TEOS) layer was deposited on a silicon wafer to a thickness of 6000 kPa by chemical vapor deposition (CVD). ARC for KrF was coated with 580 kPa on the plasma enhanced TIOS layer, and baked at 240 ° C. for 60 seconds. Thereafter, 7500 7 of KrF PR was coated on the silicon ARC and baked at 110 ° C. for 60 seconds, followed by exposure, followed by development with TMAH (2.38 wt% aqueous solution). The photomask used at the time of exposure has a pattern of contact and holes 200 nm wide and 600 nm long. And the pattern of contact and hole of 200 nm width and 600 nm length was confirmed using FE-SEM. The sample solution prepared in Examples 1 to 7 and Comparative Example 1 was spin coated on the patterned wafer. After coating and curing at 240 ° C. for 60 seconds, the FE-SEM was used to confirm that the sample solution filled in the hole was completely filled without defects such as voids. Representatively, the results of Example 1 and Comparative Example 1 are shown in Figs. 2 and 3, respectively. As can be seen in Figures 2 and 3, the sample solution of Example 1 according to the present invention was completely filled without a hole in the hole, the sample solution of Comparative Example 1 was voided, the solution was not completely filled in the hole.

The present invention has been described in detail with reference to preferred embodiments, but the present invention is not limited to the above embodiments, and various modifications may be made by those skilled in the art within the scope of the technical idea of the present invention. It is possible.

1 is a view showing a process of forming a wiring of a semiconductor device using the gap-fill composition of the present invention.

FIG. 2 is an FE-SEM photograph of the sample solution of Example 1 spin-coated onto a patterned wafer and then cured.

FIG. 3 is a FE-SEM photograph of the sample solution of Comparative Example 1 spin-coated on a patterned wafer and then cured.

Claims (8)

A compound having a weight average molecular weight (Mw) of 1,000 to 20,000 and selected from the group consisting of an aromatic ring-containing compound represented by the following general formula (1) or (2) and a combination thereof; And an organic solvent comprising: [Formula 1]

Wherein n is in the range of 1 ≦ n ≦ 190, R ₁ and R ₂ are each independently any one of the following Formulas 3 to 5, R ₃ is represented by the following formula (6), R ₄ And R ₅ are each independently hydrogen or alkyl. [Formula 2]

Wherein n is in the range of 1 ≦ n ≦ 190, R ₆ is any one of the following Formulas 3 to 5, R ₇ is represented by the following formula (6), R ₈ to R ₁₁ are each independently hydrogen or alkyl. [Formula 3]

In Formula 3, Ra and Rb are each independently hydrogen, substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl, hydride Hydroxy, substituted or unsubstituted C1 to C10 alkoxy, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C30 heteroaryl, and substitution Or unsubstituted C1 to C20 heterocycloalkyl, At least one of Ra and Rb is hydroxy, alkoxy, or substituted alkoxy, l and m are each 0 to 4 and the sum of 1 and m is 4 or less. [Formula 4]

In Formula 4, Ra to Rd are each independently hydrogen, substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl, hydride Hydroxy, substituted or unsubstituted C1 to C10 alkoxy, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C30 heteroaryl, and substitution Or unsubstituted C1 to C20 heterocycloalkyl, At least one of Ra to Rd is hydroxy, alkoxy, or substituted alkoxy, l, m, p and q are each 0-4 and 1 + m + p + q is 6 or less. [Formula 5]

In Formula 5, Ra to Rf are each independently hydrogen, substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl, hydride Hydroxy, substituted or unsubstituted C1 to C10 alkoxy, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C30 heteroaryl, and substitution Or unsubstituted C1 to C20 heterocycloalkyl, At least one of Ra to Rf is hydroxy, alkoxy, or substituted alkoxy, l, m, p and q are each 0-4 and 1 + m + p + q is 6 or less. [Formula 6]

In Formula 6, Rg and Rj are each independently substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl, hydroxy, Substituted or unsubstituted C1 to C10 alkoxy, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C30 heteroaryl, and substituted or non- Selected from the group consisting of substituted C1 to C20 heterocycloalkyl, Ar is a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C2 to C60 heteroaryl group, a substituted or unsubstituted C7 to C30 arylalkyl group and a substituted or unsubstituted C4 to C30 heteroaryl May be selected from the group consisting of alkyl groups, r is an integer from 0 to 2, k is an integer of 1-2. The method of claim 1, The aromatic ring-containing compound is used in 1 to 30 parts by weight based on 100 parts by weight of an organic solvent. The method of claim 1, Wherein the gap-fill composition further comprises 0.001 to 0.05 parts by weight of catalyst based on 100 parts by weight of the gap-fill composition. The method of claim 3, The catalyst is p - toluenesulfonic acid monohydrate (p -toluenesulfonic acid mono hydrate), pyridinium P - toluenesulfonate (Pyridinium P -toluene sulfonate), 2,4,4,6- tetrabromo-necked claw-hexadiene-one, benzoin A gap-fill composition comprising intosylate, 2-nitrobenzyl tosylate, alkyl esters of organic sulfonic acids, 2-methylimidazole, and combinations thereof. The method of claim 1, Wherein the gap-fill composition further comprises 0.05 to 3 parts by weight of a crosslinking agent based on 100 parts by weight of the gap-fill composition. The method of claim 5, The cross-linking agent is any one selected from the group consisting of amino resin, melamine resin, glycoluril compound, bisepoxy clock compound, and combinations thereof. (a) forming a first insulating film in the lower layer by the lower wiring; (b) selectively removing the first insulating film to form a via hole for opening the lower metal wire; (c) embedding the via hole with the gap-fill composition according to any one of claims 1 to 6 and then thermosetting to form a gap-fill cured film; (d) forming a second insulating film on the first insulating film; (e) selectively removing the second insulating film to form trench holes for opening the gap-fill cured film; (f) removing the gap-fill cured film; And and (g) filling the via hole and the trench hole with a conductive material to form an upper wiring. (a) forming a first insulating film, a first etch stop film, a second insulating film, and a second etch stop film on the semiconductor substrate in sequence; (b) forming a resist mask having a pattern for forming a via hole on the second etch stop layer; (c) forming a via hole through the resist mask to a first insulating film; (d) embedding the gap-fill composition according to any one of claims 1 to 6 in the via hole and thermally curing to form a gap-fill cured film; (e) etching and removing the gap-fill cured film leaving a part of the bottom of the via hole; (f) forming a resist mask having a pattern for forming a trench hole in the second etch stop layer; (g) forming a trench hole in the second insulating film through the resist mask, and simultaneously removing the gap-fill composition remaining in the bottom of the via hole; (h) forming a top wiring by filling a conductive material in the trench holes and via holes.

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