KR20070106286A - Method of forming titanium oxide with rutile structure and method of manufacturing capacitor using the same - Google Patents

Abstract

A method for forming a titanium oxide with a crystallized rutile structure is provided to guarantee excellent thermal stability without deterioration of an electrode material in forming noble metal as an electrode and improve a leakage current characteristic and a breakdown voltage characteristic by using a TiO2 thin film with a crystallized rutile structure as a dielectric layer in a deposition process. A Ti precursor and at least NH3 are crystallized to a rutile structure in a deposition process by using an ALD(atomic layer deposition) process. The Ti precursor includes oxygen. In the ALD process, a unit cycle composed of a Ti precursor injection, a purge gas injection, an NH3 injection and a purge gas injection is repeatedly performed wherein the Ti precursor injection, the purge gas injection, the NH3 injection and the purge gas injection are sequentially performed.

Description

METHODS OF FORMING TITANIUM OXIDE WITH RUTILE STRUCTURE AND METHOD OF MANUFACTURING CAPACITOR USING THE SAME}

1 is a view showing the structure of a capacitor using a TiO ₂ thin film according to the prior art,

2 is a view showing an ALD deposition process for depositing a TiO ₂ thin film crystallized in a rutile structure according to a first embodiment of the present invention;

3 is a view showing an ALD deposition process for depositing a TiO ₂ thin film crystallized in a rutile structure according to a second embodiment of the present invention;

4 is a view showing an ALD deposition process for depositing a TiO ₂ thin film crystallized in a rutile structure according to a first embodiment of the present invention;

5A and 5B illustrate the structure of a cylindrical and a concave capacitor according to an embodiment of the present invention;

FIG. 6 is a diagram illustrating a structure of a stack capacitor employing a TiO ₂ thin film crystallized in a rutile structure as a dielectric film;

FIG. 7 illustrates a structure of a capacitor including a dielectric film in which a TiO ₂ thin film crystallized in a rutile structure and an aluminum oxide film are laminated;

8 is a view showing a structure of a capacitor employing a dielectric film in which an aluminum oxide film and a TiO ₂ thin film crystallized in a rutile structure are laminated;

FIG 9 illustrates the structure of a capacitor employing a dielectric film by laminating a thin film of TiO ₂ crystallizes in the TiO ₂ thin film, an aluminum oxide and rutile-structure crystallized in rutile structure diagram,

10 is a view showing the structure of a capacitor employing a dielectric film in which a TiO ₂ thin film crystallized in a rutile structure and an aluminum oxide film are mixed.

* Explanation of symbols for the main parts of the drawings

21, 31, 41, 51: lower electrode 22, 32, 42, 52: dielectric film

23, 33, 43, 53: upper electrode

The present invention relates to a method for manufacturing a capacitor of a semiconductor device, and more particularly, to a method for manufacturing a capacitor of a semiconductor device using a titanium oxide film (TiO ₂ ) as a dielectric film.

Recently, due to the development of miniaturized semiconductor processing technology, as the integration of memory devices is accelerated, the unit cell area is greatly reduced and the operating voltage is reduced. However, despite the reduction of the cell area, sufficient capacitor capacity of about 25 fF or more per cell must be continuously required to prevent soft errors and refresh time.

Therefore, in the case of DRAM capacitors currently using silicon nitride (Si3N4) deposited using a Di-Chloro-Silane (DCS) gas as a dielectric film, 3 has an electrode surface having a hemispherical structure with a large surface area to secure a capacitor capacity. As the lower electrode is formed in the dimensional form, the height of the capacitor is continuously increased.

However, when the capacitor height is increased, the depth of focus is not secured during the subsequent exposure process due to the large step between the cell region and the peripheral region, which adversely affects the process, thus sufficient capacitor required in the next-generation DRAM of 256M or more. There is a limit to securing capacity.

Therefore, in order to secure sufficient capacitor capacity while applying an appropriate capacitor height, development of a capacitor by applying a titanium oxide film having a large dielectric constant (hereinafter referred to as TiO ₂ ) has been made in earnest.

A diagram Figure 1 shows a structure of a capacitor using a TiO ₂ thin film according to the prior art, the upper portion of the lower electrode 11, lower electrode 11 TiO ₂ thin film 12, and a TiO ₂ thin film 12 on the It consists of an electrode 13. Here, the TiO ₂ thin film is deposited by ALD (Atomic Layer Deposition) or CVD (Chemical Vapor Deposition) method, it is formed using a Ti precursor and an oxidizer (Oxidant).

In order to obtain a large dielectric constant in the TiO ₂ thin film 12 of the prior art is known to have a dielectric constant, and TiO ₂ is to be crystallized, especially in the anatase (anatase) it is higher than the rutile structure of TiO ₂ (rutile) structure. Typically, TiO ₂ has an anatase structure that forms a sharp abstract or plate-like crystalline structure and a rutile structure that forms a columnar or acicular crystalline structure.

However, in general, the TiO ₂ thin film of FIG. 1 deposited by ALD or CVD method has an amorphous or anatase structure, and in order to obtain a rutile structure, an additional heat treatment at high temperature is required, which makes the process complicated. . For example, TiO ₂ of the anatase structure is crystallized into a rutile structure at a high temperature of 500 ° C. or higher.

On the other hand, noble metals such as Pt, Ru, Ir, and the like are used as the lower electrode and the upper electrode material of the capacitor employing a high-k dielectric film such as TiO ₂ . Since the phenomenon of deterioration occurs, it is difficult to easily obtain the rutile structure of TiO ₂ because the temperature cannot be raised to 500 ° C. or more during the high temperature heat treatment proceeding to obtain the rutile structure.

Therefore, it is difficult to apply the TiO ₂ thin film as a capacitor dielectric film of the next generation DRAM due to the above reasons.

The present invention has been proposed to solve the above problems of the prior art, by applying a TiO ₂ thin film as a dielectric film, by having a rutile structure already at a low temperature deposition step by lowering the subsequent heat treatment temperature to prevent degradation of the upper and lower electrodes Accordingly, an object of the present invention is to provide a method of forming a titanium oxide film (TiO ₂ ) crystallized in a rutile structure capable of securing sufficient capacitor capacity required for high integration device operation while improving the reliability of a capacitor, and a method of manufacturing a capacitor using the same.

The method of forming the titanium oxide film of the present invention for achieving the above object is characterized in that the Ti precursor and at least NH ₃ is crystallized to a rutile structure in the deposition process through an atomic layer deposition method using a reaction gas, the atomic layer deposition method The Ti precursor injection, purge gas injection, the NH ₃ injection, purge gas injection in the order of repeating the cycle, wherein the Ti precursor, characterized in that using a Ti precursor containing oxygen, The atomic layer deposition method repeats the unit cycle consisting of the Ti precursor injection, purge gas injection, oxidant and NH ₃ simultaneous injection, purge gas injection, or the Ti precursor injection, purge gas injection, oxidant injection To repeat the unit cycle consisting of the purge gas injection, proceed with the unit cycle while continuing to inject the NH ₃ The Ti precursor is characterized by using a Ti precursor that does not contain oxygen. In the atomic layer deposition method, a deposition temperature of 200 to 350 ° C. and a pressure of 0.1 to 10 torr are used, and the flow rate of NH ₃ is 100 to 1000 sccm.

In addition, the method of manufacturing a capacitor of the present invention comprises the steps of forming a lower electrode, forming a titanium oxide film crystallized in a rutile structure in the deposition process through an atomic layer deposition method using at least NH ₃ using a reaction gas on the lower electrode, And forming an upper electrode on the titanium oxide film crystallized in the rutile structure.

Hereinafter, the preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the technical idea of the present invention. .

Embodiments of the present invention described below relate to an ALD method for depositing a TiO ₂ thin film, and in particular, to allow the TiO ₂ thin film to have crystallization of rutile structure in a low temperature deposition step when the ALD method is applied.

ALD deposition method of the TiO ₂ thin film crystallized in rutile structure will be described in detail as follows.

Hereinafter, in the first to third embodiments, the Ti precursor is used as TTIP (Titanium Tetrakis-IsoPropoxide) containing oxygen of an alkoxide (Alkoxide) series, or TDMAT (Tetra DiMethyl Amino Titanium). Alternatively, a precursor that does not contain oxygen of an amine series of TEMAT (Tetrakis Ethyl Methyl Amino Titanium) or a halide series of TiCl ₄ or TiI ₄ may be used.

The purge gas may be an inert gas such as Ar, and the reaction gas may be NH ₃ alone or NH ₃ and an oxidant may be used at the same time. As described later, when NH ₃ is used alone, the Ti precursor contains oxygen, and when NH ₃ and the oxidant are used simultaneously, the Ti precursor does not contain oxygen.

In the ALD deposition process, the deposition temperature is low at 200 to 350 ° C., the pressure is 0.1 to 10 torr, and the flow rate of NH ₃ is 100 to 1000 sccm.

(First Embodiment)

2 is a view showing an ALD deposition process for depositing a TiO ₂ thin film crystallized in a rutile structure according to a first embodiment of the present invention.

As shown in FIG. 2, a unit cycle consisting of Ti precursor injection, purge gas injection, NH ₃ injection, and purge gas injection is repeated.

First, Ti precursor is injected to adsorb Ti precursor on the sample surface. In this case, the Ti precursor is used as TTIP containing an alkoxide-based oxygen, an amine-based TDMAT or TEMAT, or a halide-based TiCl ₄ or TiI ₄ . Can be used.

Next, purge gas is injected to purge the unreacted Ti precursor. At this time, the purge gas uses an inert gas such as Ar.

Next, NH ₃ is injected as a reaction gas, and the Ti precursor adsorbed is decomposed to deposit a TiO ₂ thin film. At this time, TiO ₂ thin film is deposited even if NH ₃ is injected into the reaction gas, rather than oxidizer. This is because when Ti precursor contains oxygen, decomposition occurs without oxidizer due to the catalytic properties of NH ₃ . This is because the TiO ₂ thin film is deposited, and when the NH ₃ gas is used as the reaction gas, the TiO ₂ thin film can be crystallized to a rutile structure even at a low temperature.

Next, a purge gas is injected to remove reaction byproducts. At this time, the purge gas uses an inert gas such as Ar.

(Second Embodiment)

3 is a view showing an ALD deposition process for depositing a TiO ₂ thin film crystallized in a rutile structure according to a second embodiment of the present invention.

As shown in FIG. 3, a unit cycle consisting of Ti precursor injection, purge gas injection, oxidant and NH ₃ injection, and purge gas injection is repeated.

First, Ti precursor is injected to adsorb Ti precursor on the sample surface. In this case, the Ti precursor is used as TTIP containing an alkoxide-based oxygen, an amine-based TDMAT or TEMAT, or a halide-based TiCl ₄ or TiI ₄ . Can be used.

Next, purge gas is injected to purge the unreacted Ti precursor. At this time, the purge gas uses an inert gas such as Ar.

Next, an oxidant and NH ₃ are simultaneously injected as a reaction gas to decompose the adsorbed Ti precursor to deposit a TiO ₂ thin film. At this time, if a reaction gas at the same time injecting an oxidant (Oxidant) and NH ₃ there is TiO ₂ thin film is deposited, where the reason for injecting oxidant and NH ₃ at the same time as if it is not the Ti precursor containing oxygen, NH ₃ is It serves as a catalyst to decompose the Ti precursor and an oxidant serves to oxidize Ti in the decomposed Ti precursor. As a result, when the NH ₃ gas is used as the reaction gas, the TiO ₂ thin film can be crystallized into a rutile structure even at low temperatures. Preferably, the oxidant uses H ₂ O, O ₃ or O ₂ plasma.

Next, a purge gas is injected to remove reaction byproducts. At this time, the purge gas uses an inert gas such as Ar.

(Third Embodiment)

4 is a view showing an ALD deposition process for depositing a TiO ₂ thin film crystallized in a rutile structure according to a third embodiment of the present invention.

As shown in FIG. 4, a unit cycle consisting of a Ti precursor injection, a purge gas injection, an oxidant injection, and a purge gas injection is repeatedly performed, but the progress of the unit cycle continues from the beginning while NH ₃ gas is injected. Proceed. In the third embodiment, like in the second embodiment, the Ti precursor does not contain oxygen.

First, the Ti precursor is injected into the chamber into which the NH ₃ gas is injected to adsorb the Ti precursor onto the sample surface. In this case, the Ti precursor is used as TTIP containing an alkoxide-based oxygen, an amine-based TDMAT or TEMAT, or a halide-based TiCl ₄ or TiI ₄ . Can be used.

Next, purge gas is injected to purge the unreacted Ti precursor. At this time, the purge gas uses an inert gas such as Ar.

Next, an oxidant is injected as a reaction gas to decompose the adsorbed Ti precursor to deposit a TiO ₂ thin film. At this time, when an oxidant (Oxidant) is injected as a reaction gas, a TiO ₂ thin film is deposited, wherein the NH ₃ gas continuously injected serves as a catalyst for decomposing the Ti precursor and the oxidant oxidizes Ti in the decomposed Ti precursor. Play a role. As a result, when the TiO ₂ thin film is deposited by injecting an oxidant while the NH ₃ gas is continuously injected, the TiO ₂ thin film can be crystallized to a rutile structure even at a low temperature. Preferably, the oxidant uses H ₂ O, O ₃ or O ₂ plasma.

Next, a purge gas is injected to remove reaction byproducts. At this time, the purge gas uses an inert gas such as Ar.

The TiO ₂ thin films crystallized into rutile structures according to the first to third embodiments may be deposited to a thickness of 30 to 100 GPa, and after the deposition, a heat treatment process may be selectively performed using rapid heat treatment or furnace annealing.

5A and 5B are views showing the structure of the cylindrical and concave capacitor according to an embodiment of the present invention, Figure 5a is a capacitor having a lower electrode module of the cylinder structure, Figure 5b is a lower portion of the concave structure A capacitor having an electrode module.

The manufacturing method of the capacitor illustrated in FIGS. 5A and 5B is as follows.

First, a first interlayer insulating film 102 is formed on the semiconductor substrate 101, and a storage node contact plug 103 is formed through the first interlayer insulating film 102 and connected to the semiconductor substrate 101.

Subsequently, a hole for exposing the surface of the storage node contact plug 103 is formed by forming a second interlayer insulating layer 104 on the storage node contact plug 103 and performing an etching process to provide a space in which the lower electrode is to be formed. Reference numerals are omitted). Subsequently, the lower electrode 21 is formed in the hole. Subsequently, when the second interlayer dielectric film 104 is removed through a wet deep out, the TiO ₂ thin film crystallized in a rutile structure becomes a lower electrode module having a cylindrical structure as shown in FIG. 2A and the second interlayer dielectric film 104 remains. Deposition of 22 results in a lower electrode module having a concave structure as in FIG. 5B.

Subsequently, a metal film or a doped polysilicon film such as TiN, Ru, TaN, W, WN and Pt is deposited as the lower electrode material. Subsequently, the lower electrode material is separated by the CMP process or the etch back process, and then the capacitor oxide film is removed to form the lower electrode 21 in the form of a cylinder.

Subsequently, a TiO ₂ thin film 22 crystallized in a rutile structure is formed on the lower electrode 21.

Here, the TiO ₂ thin film 22 crystallized in a rutile structure is deposited to have a thickness of 30 to 100 kPa by an ALD method using at least NH ₃ as a reaction gas (see Examples 1 to 3). As in the above-described embodiments, when the TiO ₂ thin film 22 is deposited by the ALD method, when NH ₃ is used as the reaction gas, the oxidizing agent may be formed by the catalytic properties of NH ₃ when the Ti precursor contains oxygen. Decomposition takes place without the use of oxides, and crystallization is possible even at low temperatures. In addition, since Ti precursor does not contain oxygen, it may have a high dielectric constant by crystallizing rutile structure at low temperature even when injected simultaneously with an oxidizing agent.

Next, the upper electrode 23 is formed on the TiO ₂ thin film 22 crystallized in a rutile structure. In this case, the material used as the upper electrode 23 is a metal film such as TiN, Ru, TaN, W, WN and Pt or a doped polysilicon film.

Meanwhile, after depositing the TiO ₂ thin film 22 crystallized in a rutile structure, a heat treatment process may be selectively performed by using rapid heat treatment or furnace annealing, and the heat treatment process may be performed after the upper electrode 23 is formed. .

5A and 5B, a capacitor having a cylindrical lower electrode and a concave lower electrode has been described. However, the TiO ₂ thin film crystallized by the rutile structure of the present invention can be applied to a stacked capacitor.

Figure 6 is a dielectric layer which is a view showing the structure of a stacked capacitor employs a TiO ₂ thin film crystallized in rutile structure as the dielectric film, formed between the lower electrode 21 and upper electrode 23 is crystallized in rutile structure TiO ₂ It is a thin film 22. Here, the lower electrode 21 and the upper electrode 23 use a noble metal.

FIG. 7 illustrates a structure of a capacitor employing a dielectric film in which a TiO ₂ thin film crystallized in a rutile structure and an aluminum oxide film are stacked, wherein a dielectric film 32 formed between the lower electrode 31 and the upper electrode 33 is formed. The TiO ₂ thin film 32a crystallized in a rutile structure and the aluminum oxide films Al ₂ O ₃ and 32b are stacked in this order.

FIG. 8 is a view showing the structure of a capacitor employing a dielectric film in which an aluminum oxide film and a TiO ₂ thin film crystallized in a rutile structure are laminated. The dielectric film 32 formed between the lower electrode 31 and the upper electrode 33 is Aluminum oxide films (Al ₂ O ₃ , 32b) and a TiO ₂ thin film 32a crystallized in a rutile structure are laminated in this order.

Figure 9 is a TiO ₂ thin film, and a diagram showing a structure of adopting the TiO dielectric layer by depositing a _second thin film crystallized by the aluminum oxide and the rutile structure, the capacitor lower electrode 41 and upper electrode 43 is crystallized in rutile structure _Three layers in which the dielectric film 42 formed therebetween is laminated in the order of the TiO ₂ thin film 42a crystallized in a rutile structure, aluminum oxide films (Al ₂ O ₃ , 42b), and the TiO ₂ thin film 42c crystallized in a rutile structure. Has a structure.

FIG. 10 illustrates a structure of a capacitor including a dielectric film obtained by mixing a TiO ₂ thin film and an aluminum oxide film crystallized in a rutile structure, wherein a dielectric film 52 formed between the lower electrode 51 and the upper electrode 53 is formed. A TiO ₂ -Al ₂ O ₃ thin film 52 having a rutile structure in which a TiO ₂ thin film crystallized in a rutile structure and an aluminum oxide film (Al ₂ O ₃ ) are mixed.

In the capacitors shown in FIGS. 6 to 10, the total thickness of the dielectric film formed of a double film, triple film, and mixed film structure, including the case of using a single TiO ₂ thin film, is preferably 30 to 100 mm thick, and an aluminum oxide film. When (Al ₂ O ₃ ) is applied to form a dielectric film with a double film, triple film, and mixed film, the equivalent oxide film thickness is due to the leakage current characteristics of the aluminum oxide film (Al ₂ O ₃ ), which is relatively superior to the TiO ₂ thin film. Tox can be lowered further.

Meanwhile, in the capacitor illustrated in FIGS. 6 to 10, the aluminum oxide film (Al ₂ O ₃ ) is deposited by the ALD method in the same manner as the TiO ₂ thin film.

For example, a unit cycle consisting of Al precursor injection, purge gas injection, oxidant injection, and purge gas injection is repeatedly performed and deposited. At this time, the Al precursor is used as an organometallic compound of MPA (Methyl Pyrrolidine Alane) or TMA (trimethyl-aluminum), the reaction gas is H ₂ O, O ₂ or O ₂ plasma, the purge gas Use inert gas.

And, TiO ₂ -Al ₂ O ₃ thin film of a mixture of rutile structure is crystallized in rutile structure such as TiO ₂ thin film 10 and an aluminum oxide (Al ₂ O ₃₎ is in one example, of the TiO ₂ thin film crystallized in rutile structure 2 to 4 cycles, and an aluminum oxide (Al ₂ O ₃ ) cycle consisting of an Al precursor injection, a purge gas injection, an oxidant injection, and a purge gas injection are repeatedly performed at a predetermined ratio for deposition.

6 and 10, the lower electrode and the upper electrode may be formed of any one metal film selected from the group consisting of TiN, Ru, TaN, W, WN, and Pt, or polysilicon doped with impurities. Form into a film.

Although the technical spirit of the present invention has been described in detail according to the above preferred embodiment, it should be noted that the above embodiment is for the purpose of description and not of limitation. In addition, those skilled in the art will understand that various embodiments are possible within the scope of the technical idea of the present invention.

As described above, the present invention applies a TiO ₂ thin film crystallized in a rutile structure in the deposition step as a dielectric film, thereby ensuring excellent thermal stability without deterioration of electrode materials when noble metal is used as an electrode, thereby improving leakage current characteristics and breakdown voltage characteristics. In addition, the reliability of the dielectric film can be improved, and sufficient capacitor capacity required for high integration device operation can be ensured.

Claims (27)

A method of forming a titanium oxide film in which a Ti precursor and at least NH ₃ are crystallized to a rutile structure during deposition through atomic layer deposition using a reaction gas. The method of claim 1, The atomic layer deposition method, Method of forming a titanium oxide film is repeated in the unit cycle consisting of the Ti precursor injection, purge gas injection, NH ₃ injection, purge gas injection. The method of claim 2, The Ti precursor is a method of forming a titanium oxide film using a Ti precursor containing oxygen. The method of claim 3, The Ti precursor containing oxygen is a method of forming a titanium oxide film using an alkoxide-based Ti precursor. The method of claim 1, The atomic layer deposition method, And a method of forming a titanium oxide film by repeating a unit cycle consisting of the Ti precursor injection, the purge gas injection, the oxidant and the NH ₃ simultaneous injection, and the purge gas injection. The method of claim 1, The atomic layer deposition method, A method of forming a titanium oxide film in which a unit cycle consisting of the Ti precursor injection, the purge gas injection, the oxidant injection, and the purge gas injection is repeatedly performed, and the unit cycle is continued while the NH ₃ is continuously injected. The method according to claim 5 or 6, The Ti precursor is a method of forming a titanium oxide film using a Ti precursor that does not contain oxygen. The method of claim 7, wherein The Ti precursor which does not contain the said oxygen is a titanium oxide film formation method using the amine type or halide type Ti precursor. The method according to claim 5 or 6, The method for producing a capacitor, wherein the oxidant uses H ₂ O, O _3, or O ₂ plasma. The method according to any one of claims 1, 2, 5 or 6, The atomic layer deposition method uses a deposition temperature of 200 to 350 ° C. and a pressure of 0.1 to 10 torr, and a flow rate of NH ₃ is 100 to 1000 sccm. Forming a lower electrode; Forming a titanium oxide film crystallized in a rutile structure on the lower electrode through an atomic layer deposition method using at least NH ₃ as a reaction gas; And Forming an upper electrode on the titanium oxide film crystallized in the rutile structure Method of manufacturing a capacitor comprising a. The method of claim 11, Forming the titanium oxide film is, A method of manufacturing a capacitor which repeats a unit cycle consisting of Ti precursor injection, purge gas injection, NH ₃ injection, and purge gas injection. The method of claim 12, The said Ti precursor is a manufacturing method of the capacitor which uses the Ti precursor containing oxygen. The method of claim 13, The said Ti precursor containing oxygen uses the alkoxide type Ti precursor, The manufacturing method of the capacitor. The method of claim 11, Forming the titanium oxide film is, A method of manufacturing a capacitor which repeats a unit cycle consisting of Ti precursor injection, purge gas injection, oxidant and NH ₃ simultaneous injection, and purge gas injection. The method of claim 11, Forming the titanium oxide film is, A method of manufacturing a capacitor in which a unit cycle consisting of a Ti precursor injection, a purge gas injection, an oxidant injection, and a purge gas injection is repeatedly performed, but the unit cycle is continued while the NH ₃ is continuously injected. The method according to claim 15 or 16, The said Ti precursor is a manufacturing method of the capacitor which uses the Ti precursor which does not contain oxygen. The method of claim 17, The said Ti precursor which does not contain oxygen uses the amine type or halide type Ti precursor, The manufacturing method of the capacitor. The method according to claim 15 or 16, The method for producing a capacitor, wherein the oxidant uses H ₂ O, O _3, or O ₂ plasma. The method according to any one of claims 11, 12, 15 or 16, In the atomic layer deposition method, a deposition temperature of 200 to 350 ° C. and a pressure of 0.1 to 10 torr are used, and the flow rate of NH ₃ is 100 to 1000 sccm. The method of claim 11, After the titanium oxide film is formed or after the upper electrode is formed, rapid heat treatment or furnace annealing is performed. The method of claim 11, Forming an aluminum oxide film on the titanium oxide film to form a dielectric film having an Al ₂ O ₃ / TiO ₂ structure of the capacitor manufacturing method. The method of claim 11, Forming an aluminum oxide film before forming the titanium oxide film, a method of manufacturing a capacitor, characterized in that to form a dielectric film with a TiO ₂ / Al ₂ O ₃ structure. The method of claim 11, After the titanium oxide film is formed, an aluminum oxide film and a titanium oxide film are sequentially formed to form a dielectric film having a TiO ₂ / Al ₂ O ₃ / TiO ₂ structure. The method according to any one of claims 22 to 24, The aluminum oxide film is a method of manufacturing a capacitor, characterized in that formed by atomic layer deposition. The method of claim 11, The aluminum oxide film is mixed with the titanium oxide crystallized in the rutile structure to form a dielectric film mixed with a TiO ₂ -Al ₂ O ₃ structure. The method of claim 11, The lower electrode and the upper electrode, A method of manufacturing a capacitor formed of any one of a metal film selected from the group consisting of TiN, Ru, TaN, W, WN and Pt or a doped polysilicon film.

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