KR100866305B1 - High-k metal oxide thin films, method for forming thereof and devices comprising the same - Google Patents

Abstract

The present invention provides a high dielectric constant metal oxide film including a high dielectric constant metal oxide film whose dielectric constant changes according to the crystal phase and crystallographic orientation, a crystal phase having a high dielectric constant, and a metal oxide film which is periodically repeatedly added in small amounts to stabilize the orientation, and a method of manufacturing the same; The present invention relates to a semiconductor device or a battery electronic system device including the same, and the metal oxide film according to the present invention has excellent electrical characteristics such as low equivalent oxide film thickness and low leakage current, and thus may be usefully used as a semiconductor device or an electric and electronic system device. .

High dielectric constant oxide film, crystal phase transformation, preferential orientation, hafnium-aluminum oxide film, atomic layer deposition method

Description

High-k metal oxide thin films, methods for manufacturing the same, and devices including the same

1 is a graph showing an X-ray diffraction analysis showing monoclinic crystallization after heat treatment of a hafnium oxide film deposited using a conventional atomic layer deposition method;

2 is a process flow chart of a method for stabilizing the crystal phase and preferred orientation having a high dielectric constant and formation of a high dielectric constant metal oxide film according to the present invention;

3 is an X-ray diffraction graph of a hafnium-aluminum oxide film prepared according to Example 1 of the present invention after heat treatment at 700 ° C. for 60 seconds in a nitrogen atmosphere.

4 is a graph showing changes in dielectric constant before and after heat treatment of a hafnium-aluminum oxide film prepared according to Example 1 of the present invention.

5 is a graph showing changes in leakage current before and after heat treatment of the hafnium-aluminum oxide film prepared according to Example 1 of the present invention.

The present invention relates to a high dielectric constant metal oxide film, a method for manufacturing the same, and a device including the same, and more particularly, to stabilize a high dielectric constant metal oxide film whose dielectric constant changes according to crystal phase and crystallographic orientation, a crystal phase having high dielectric constant, and preferential orientation. The present invention relates to a high dielectric constant metal oxide film including a metal oxide film periodically and repeatedly added in a small amount, a method for manufacturing the same, and a semiconductor device or a battery electronic system device including the same.

Currently, many kinds of oxide films are used in the semiconductor industry. Among them, a silicon oxide film (SiO ₂ ) can be grown directly on a silicon substrate in an oxidizing atmosphere, and thus is most frequently used in various semiconductor devices. In particular, since the silicon oxide film thus grown has an amorphous structure and does not provide a leakage current path through the grain boundary, it is widely used as a gate oxide film of a transistor, a capacitor oxide film of a volatile memory device, a tunnel of a nonvolatile memory device, and a control oxide film.

However, as the degree of integration of semiconductor elements increases, the thickness of the silicon oxide film gradually decreases, and a thickness of 2 nm or less is expected. However, silicon oxide thinner than 2nm faces physical limitations that can no longer be applied to semiconductor devices due to the high leakage current caused by the tunneling of electrons.

Therefore, the research on the metal oxide film having a high dielectric constant to replace the silicon oxide film has been intensively conducted. In the present invention, a metal oxide film having a high dielectric constant (hereinafter, referred to as a “high dielectric constant metal oxide film”) means a metal oxide film having a dielectric constant of about 10 or more that is higher than the dielectric constant of 3.9 of the silicon oxide film. Recently, high-k dielectric metal oxide films include aluminum oxide film (Al ₂ O ₃ ), hafnium oxide (HfO ₂ ), zirconium oxide (ZrO ₂ ), titanium oxide (TiO ₂ ), and tantalum oxide (Ta ₂ O ₅ ).

The dielectric constant of the high dielectric constant metal oxide films is affected by the type and crystallographic orientation of the crystal phase. For example, a titanium oxide film has a dielectric constant of 50 or less when having a stable anatase phase at low temperature, and a dielectric constant increases up to 180 when having a rutile phase which is a high temperature phase (Japanese Journal of Appled Physics , 40, pp 3147 (2001).

Tantalum oxide films have the highest permittivity in the a-axis direction compared to other crystallographic orientations (Journal of Appled Physics, 86, pp 871 (1999)). In addition, a phenomenon in which the dielectric constant of hafnium or zirconium oxide is greatly changed depending on the crystal phase has been reported.

In particular, theoretical calculation results have been reported that hafnium oxide films have dielectric constants of 18, 70, and 29 when the crystal phases are monoclinic, tetragonal, and cubic, respectively. (Physical Review B, 65, pp 075105, (2002)) However, tetragonal and cubic crystals with high permittivity can be obtained thermodynamically at very high temperatures of 1720 and 2600 ° C, and have the lowest permittivity at temperatures below that. Monoclinic is stable.

1 is a graph showing an X-ray diffraction analysis showing monoclinic crystal after thermal treatment of a hafnium oxide film deposited by an atomic layer deposition method according to the prior art, as shown in FIG. It is difficult to obtain a tetragonal or cubic phase of a hafnium oxide film having hafnium oxide, and there are almost no experimental results.

The present invention is to solve the problems of the prior art as described above,

One object of the present invention is a high dielectric constant metal oxide film having a high dielectric constant improved by periodically repeatedly adding a small amount of a metal element having a valence smaller than that of the metal element constituting the metal oxide film to a high dielectric constant metal oxide film whose dielectric constant changes according to a crystal phase. To provide.

Another object of the present invention is to stabilize a crystalline phase having a high dielectric constant by periodically adding a small amount of a metal element having a valence smaller than that of the metal constituting the metal oxide film to a high dielectric constant metal oxide film whose dielectric constant varies depending on the crystal phase. At the same time to provide a method of manufacturing a high dielectric constant metal oxide film having a very high dielectric constant by first adjusting the orientation in the same crystal phase.

Still another object of the present invention is to provide a device including the high dielectric constant metal oxide film.

One aspect of the present invention for achieving the above object is a high dielectric constant metal oxide film whose dielectric constant changes according to the crystal phase and crystallographic orientation and the crystal phase having a high dielectric constant and preferential orientation to stabilize the first metal oxide film weight 1 It relates to a high dielectric constant metal oxide film including a metal oxide film repeatedly added at ˜10%.

[Formula 1]

(A _x O _y ) _m- (B _w O _z ) _n

Wherein A is at least one metal element constituting a high dielectric constant metal oxide film whose dielectric constant varies depending on the crystal phase and crystallographic orientation,

B is one or more metal elements constituting a metal oxide film which is repeatedly added in a 1-10% to the total weight of the metal oxide film periodically to stabilize the crystal phase having a high dielectric constant and preferential orientation,

O means oxygen,

x, y, w and z are each independently determined according to the type of metal element of A and B,

m and n are 1 to 10% of the total weight of the metal oxide film periodically to stabilize the high dielectric constant metal oxide film (A _x O _y ) whose dielectric constant varies according to the crystal phase and crystallographic orientation, and the crystal phase having high dielectric constant and preferred orientation. The mixing ratio of the metal oxide film (B _w O _z ) added repeatedly is m + n = 100 mol%.

The term “high dielectric constant metal oxide film whose dielectric constant changes according to crystal phase and crystallographic orientation” is a metal oxide film composed of metal element and oxygen, which has a higher dielectric constant than silicon oxide film and is in accordance with its own crystallographic or crystallographic orientation. The metal oxide film whose dielectric constant changes is called collectively.

In addition, the "metal oxide film having a high dielectric constant and a metal oxide film which is periodically added in small amounts periodically to stabilize the orientation thereof" refers to an intrinsic dielectric constant that varies depending on the crystal phase and crystallographic orientation among metal oxide films composed of metal elements and oxygen. The metal oxide film which has a valence smaller than the metal element constituting the tremor metal oxide film and which can stabilize the crystal phase having a high dielectric constant or preferential orientation among the crystal phases of the high dielectric constant metal oxide film is referred to collectively.

The high dielectric constant metal oxide film whose dielectric constant changes according to the crystal phase and crystallographic orientation is in the group consisting of hafnium oxide (HfO ₂ ), zirconium oxide (ZrO ₂ ), titanium oxide (TiO ₂ ) and tantalum oxide (Ta ₂ O ₅ ). It includes, but is not limited to, one or two or more materials selected.

The metal oxide film periodically added in small amounts to stabilize the high dielectric constant and preferential orientation includes one or more materials having a divalent or trivalent valence to induce oxygen vacancies. The materials having Al ₂ O ₃ , Y ₂ O ₃ , La ₂ O ₃ , Fe ₂ O ₃ , Ga ₂ O ₃ , Er ₂ O ₃ , Sc ₂ O ₃ , Pr ₂ O ₃ , Nd ₂ O ₃ , Ce _It may be selected from the group consisting of ₂ O ₃ , CaO, MgO and SrO, but is not limited thereto.

The metal oxide film represented by Chemical Formula 1 has a thickness of 20 to 2000 kPa, preferably 50 to 1500 kPa, and has a dielectric constant of 10 to 180, preferably 15 to 100, depending on the crystal phase and crystallographic orientation. have.

The content of the metal oxide film that is periodically added in small amounts repeatedly included in the metal oxide film represented by Formula 1 is preferably 10% or less, preferably 1 to 5% of the total metal oxide film weight. when it is more than 10% does not affect the crystal phase, and crystallographic implementation characteristics of the directional high-k metal oxide layer (a _x O _y) dielectric constant varies according to, the characteristics of small repeated addition of the metal oxide (B _w O _z) is Problems may arise that may or may not appear together.

The structure of the metal oxide film represented by Chemical Formula 1 is formed by a high dielectric constant metal oxide film whose dielectric constant changes according to a crystal phase and crystallographic orientation, and a small amount is repeatedly added periodically to stabilize the crystal phase having a high dielectric constant and preferential orientation. The metal oxide film is inserted in the form of particles;

The high dielectric constant metal oxide film whose dielectric constant changes in accordance with the crystal phase and crystallographic orientation and the crystal phase having high dielectric constant and the metal oxide film which are periodically added in small amounts in order to stabilize preferential orientation are completely mixed in an indistinguishable form from each other;

Or a lamination structure in which a high dielectric constant metal oxide film whose dielectric constant changes according to the crystal phase and crystallographic orientation, and a metal oxide film periodically and repeatedly added in small amounts in order to stabilize the preferred orientation are repeated in a thickness of 5 to 60 Å. It is preferable.

The high dielectric constant metal oxide film according to the present invention has the following advantages.

First, when a high dielectric constant metal oxide film whose dielectric constant changes according to the crystal phase and crystallographic orientation alone is used as a high dielectric constant metal oxide film, a relatively high dielectric constant crystal phase or crystallographic orientation is stabilized only at a high temperature. It cannot be obtained in the temperature range, making it a short-term alternative for single application.

Second, according to the mixing ratio and the mixing structure of the “high dielectric constant oxide film whose dielectric constant varies according to the crystalline phase and crystallographic orientation” and the “crystalline phase having a high dielectric constant and a metal oxide film which is periodically repeatedly added in small amounts to stabilize preferred orientation” Dielectric properties of the high-k metal oxide film can be variously designed according to the requirements of "semiconductor devices and electrical and electronic system devices."

Another aspect of the present invention for achieving the above object is (a) one kind of metal oxide film which is repeatedly added to 1-10% of the total metal oxide film weight periodically to stabilize the crystal phase having high dielectric constant and preferred orientation. Forming a metal oxide film that is repeatedly added to 1 to 10% by weight of the total metal oxide film in order to stabilize the crystal phase and preferential orientation having a high dielectric constant including the step of injecting the above metal precursor to adsorb on the substrate, and oxidized ; (b) A dielectric constant varies according to the crystal phase and crystallographic orientation, comprising injecting and oxidizing at least one metal precursor constituting a high-k dielectric metal oxide film, the dielectric constant of which varies depending on the crystal phase and crystallographic orientation, to the substrate. Forming a metal oxide film; And (c) depositing the metal oxide film formed in step (a) and the metal oxide film formed in step (b) by vacuum deposition. .

[Formula 1]

(A _x O _y ) _m- (B _w O _z ) _n

In the above formula, A is one or more metal elements forming a high dielectric constant metal oxide film whose dielectric constant varies according to the crystal phase and crystallographic orientation, and is composed of hafnium (Hf), zirconium (Zr), titanium (Ti), and tantalum (Ta). Selected from the military,

B is one or more metal elements forming a metal oxide film which is repeatedly added at 1 to 10% by weight of the total metal oxide film periodically to stabilize the crystal phase having a high dielectric constant and preferential orientation, Al, Y, La, Fe, Ga, Selected from the group consisting of Er, Sc, Pr, Nd, Ce, Ca, Mg, and Sr,

O means oxygen,

x, y, w and z are each independently determined according to the type of the metal element of A and B,

m and n are 1 to 10% of the total weight of the metal oxide film periodically to stabilize the high dielectric constant metal oxide film (A _x O _y ) whose dielectric constant varies according to the crystal phase and crystallographic orientation, and the crystal phase having high dielectric constant and preferred orientation. The mixing ratio of the metal oxide film (B _w O _z ) added repeatedly is m + n = 100 mol%.

The metal precursor of step (a) or (b) is an inorganic compound containing the metal element, for example, the metal precursor of step (a) is TMA (Tri methyl aluminum; Al (CH ₃ ) ₃ ), ( Examples of the metal precursor of step b) are TEMAHf (Tetrakis ethyl methyl amino hafnium; Hf [N (CH ₃ ) (C ₂ H ₅ )] ₄ ).

The substrate of step (a) or (b) may be Si, SiO ₂ , TiN, Pt, Ru, RuO ₂ , Ru / RuO ₂ , Ir, IrO ₂ And an inorganic substrate or a plastic substrate selected from the group consisting of Ir / IrO ₂ , but is not limited thereto.

The vacuum deposition method of step (c) includes physical vapor deposition (PVD) and atomic layer deposition (ALD), including sputtering and e-beam evaporation. Chemical Vapor Deposition (CVD), including, but not limited to, a Plasma Enhanced Atomic Layer Deposition (PEALD) and the like.

The oxidant used in the vacuum deposition method may include oxygen, but may be an oxygen plasma, for example, but is not limited thereto.

Method for producing a high dielectric constant metal oxide according to the present invention may include the step of obtaining a crystalline phase film by heat treatment after the step (c), a neutral atmosphere or O ₂ selected from the group consisting of N ₂ , Ar and He , At least one second, preferably at least five seconds at a heat treatment atmosphere of an oxidizing atmosphere selected from the group consisting of H ₂ O, NO and N ₂ O and at a heat treatment temperature of 400 to 3,000 ° C., preferably 600 to 1000 ° C. Heat treatment for 1 hour.

Another aspect of the present invention for achieving the above object relates to a device comprising the high-k metal oxide film.

Examples of the device include a semiconductor device or an electrical and electronic system device including a gate oxide film of a transistor, a capacitor oxide film of a volatile memory, a tunnel or a control oxide film of a nonvolatile memory.

Hereinafter, as a preferred embodiment of the present invention, among the above-mentioned metal oxide films, "high dielectric constant metal oxide film (A _x O _y ) whose dielectric constant changes according to crystal phase and crystallographic orientation" is HfO ₂ , "crystal phase having high dielectric constant and priority. In the case where the metal oxide film B _w O _z ″ periodically added in small amounts to stabilize the orientation is formed from Al ₂ O ₃ , a crystal phase having a high dielectric constant in the hafnium-aluminum oxide film (HAO) and preferential orientation are formed. The present invention will be described in more detail.

The present invention is not limited to the embodiments described below, but as described above, "high dielectric constant metal oxide films (A _x O _y ) whose dielectric constant changes depending on the crystal phase and crystallographic orientation" and "crystal phases having a high dielectric constant And a combination of metal oxide films (B _w O _z ) ″ periodically added to 1-10% of the total metal oxide weight in order to stabilize the orientation.

In addition, although various conventional thin film formation methods such as PVD or CVD are possible to form the preferred embodiment as described above, the following description will be given of the case of using the plasma atomic layer deposition method as a non-limiting example.

The hafnium oxide film has a dielectric constant of 16-18 when having a monoclinic in the low temperature phase, while having a tetragonal or cubic crystal in the high temperature phase has a dielectric constant of 70 or 29, respectively. However, in the case of hafnium oxide films, monoclinic crystals are thermodynamically stable at temperatures of 1720 ° C or lower, tetragonal crystals at temperatures between 1720 ° C and 2600 ° C, and cubic crystals at temperatures higher than 2600 ° C.

Therefore, there is a need for a method of stabilizing a high temperature stable phase even at low temperatures. In the field of bulk ceramics formed by mixing powders, a method of stabilizing high temperature stable phase at low temperature by adding a small amount of a metal oxide film containing a small valence metal element to form oxygen vacancies has been reported (Journal of Materials Science, 27, pp 5397 (1992).

2 is a flowchart of a method of forming a high dielectric constant metal oxide film and a crystal phase having a high dielectric constant and preferential orientation according to a preferred embodiment of the present invention.

First, a substrate in which the process until the high dielectric constant metal oxide film is formed is loaded into the chamber (201). When the substrate is loaded into the chamber, a hafnium-aluminum oxide film is deposited to a desired thickness using a plasma atomic layer deposition method (202). When the deposition is completed, the substrate is taken out (203). In order to obtain a crystalline phase of the hafnium-aluminum oxide film, heat treatment is performed at or above the crystallization temperature of the hafnium-aluminum oxide film (204).

The method for forming a hafnium-aluminum high dielectric constant metal oxide film using a plasma atomic layer deposition method includes the steps of (a) injecting an aluminum precursor to chemisorbed onto a substrate, (b) injecting a purge gas, and (c) oxygen Injecting plasma to oxidize the ligand of the adsorbed aluminum precursor to form an aluminum oxide film, (d) injecting a purge gas, (e) injecting and adsorbing a hafnium precursor, and (f) injecting a purge gas. A hafnium oxide having a constant thickness through a super cycle consisting of the steps of (g) injecting an oxygen plasma to oxidize a ligand of the adsorbed hafnium precursor to form a hafnium oxide film, and (h) injecting a purge gas. An aluminum oxide film is formed. In the atomic layer deposition method, when the cycle is repeated, the thickness of the thin film increases in proportion to the number of cycles. Thus, a thin film having a desired thickness can be formed on the substrate through repeated cycles.

In order to adjust the mixing ratio of each hafnium and aluminum oxide film in the hafnium-aluminum oxide film, the steps (a) to (d) (one unit cycle of the aluminum oxide film) and (e) to (h) steps (a) as many times as desired. One unit cycle of the hafnium oxide film may be repeated to form one subcycle each. This configuration method can be represented by the following symbols.

(a, b) = (unit cycle number of aluminum oxide film, unit cycle number of hafnium oxide film)

Hereinafter, the present invention will be described in detail by way of examples, but specific process methods, specific process parameters (temperature, pressure, gas flow rate, plasma power) and specific dimensions provided in the following examples are given as examples for obtaining an optimal result. Only provided, the present invention is not limited thereto. In addition, the specific high dielectric constant metal oxide film and the component display provided in the present invention are provided as examples only, and the present invention is not limited thereto.

Example 1 Preparation of Hafnium-Aluminum Metal Oxide (1)

The hafnium-aluminum oxide film may be formed by combining metal precursors of various types of inorganic compounds including metal elements. In this embodiment, hafnium precursors include TEMAHf (Tetrakis ethyl methyl amino hafnium, Hf [N (CH ₃ ) (C)). ₂ H ₅ )] ₄ ) was used as TMA (Tri methyl aluminum, Al (CH ₃ ) ₃ ) as the aluminum precursor, and oxygen plasma was used as the oxidant.

Method for forming a hafnium-aluminum high dielectric constant metal oxide film using a plasma atomic layer deposition method in a combination as shown in Table 1 below at a process temperature of 250 ℃, (a) by injecting a TMA, an aluminum precursor for 1 second to the chemical Adsorbing, (b) injecting argon (Ar) purge gas for 5 seconds, and (c) injecting oxygen plasma for 1 second to form an aluminum oxide film by oxidizing a ligand of TMA, an adsorbed aluminum precursor. A unit cycle of an aluminum oxide film comprising (d) injecting purge gas for 5 seconds, and (e) injecting and adsorbing a hafnium precursor, TEMAHf, for 2 seconds, and (f) purging for 5 seconds. Injecting a gas, (g) injecting an oxygen plasma for 1 second to oxidize a ligand of TEMAHf, a hafnium precursor adsorbed, thereby forming a hafnium oxide film; , (h) A hafnium-aluminum metal oxide film was prepared based on the unit cycle of the hafnium oxide film formed by injecting purge gas for 5 seconds.

Table 1 shows various construction methods for forming a hafnium-aluminum oxide film in which the unit cycle number of the aluminum oxide film is 1 and the unit cycle number of the hafnium oxide film is changed from 9 to 30.

TABLE 1

Sample Aluminum unit can cycle Hafnium Unit Cycle Count Super cycle count A (1,9) One 9 100 B (1,15) One 15 63 C (1,20) One 20 48 D (1,30) One 30 32

Example 2 Preparation of Hafnium-Aluminum Metal Oxide

The hafnium-aluminum oxide film may be formed by combining metal precursors of various types of inorganic compounds including metal elements. In this embodiment, hafnium precursors include TEMAHf (Tetrakis ethyl methyl amino hafnium, Hf [N (CH ₃ ) (C)). ₂ H ₅ )] ₄ ) was used as TMA (Tri methyl aluminum, Al (CH ₃ ) ₃ ) as the aluminum precursor, water (H ₂ O) or ozone (O ₃ ) was used as the oxidizing agent.

The method for forming a hafnium-aluminum high dielectric constant metal oxide film at a process temperature of 250 degrees by using an atomic layer deposition method includes the steps of (a) injecting TMA, an aluminum precursor for 1 second, to chemically adsorb onto a substrate, and (b) 5 Injecting argon (Ar) purge gas for seconds, and (c) injecting water (H ₂ O) or ozone (O ₃ ) for 1 second to oxidize the ligand of the adsorbed aluminum precursor, TMA, to form an aluminum oxide film. (D) a unit cycle of an aluminum oxide film comprising (d) injecting purge gas for 5 seconds, and (e) injecting and adsorbing TEMAHf, a hafnium precursor, for 2 seconds, and (f) for 5 seconds. Injecting a purge gas, (g) injecting water (H ₂ O) or ozone (O ₃ ) for one second to form a hafnium oxide film by oxidizing a ligand of the adsorbed hafnium precursor, TEMAHf, and (h ) Fuzzy for 5 seconds By the unit cycle of the hafnium oxide film formed in the steps of injecting a base hafnium was prepared an aluminum metal oxide film.

Example 3 Fabrication of Semiconductor Device Containing Hafnium-Aluminum Metal Oxide

By a conventional method, a hafnium-aluminum metal oxide film prepared in Example 1 was formed on a silicon substrate, and a gate oxide film of a transistor including a hafnium-aluminum metal oxide film was prepared including polysilicon formed as a gate thereon. .

Experimental Example 1: X-ray diffraction analysis of hafnium-aluminum metal oxide film

3 shows the results of analyzing the dielectric constant after heat treatment of the hafnium-aluminum metal oxide film prepared in Example 1 using an X-ray diffractometer (XRD) at 700 ° C. for 60 seconds in a nitrogen atmosphere.

Referring to FIG. 3, it can be seen that samples A to D exhibit a high temperature tetragonal phase unlike the X-ray diffraction analysis illustrated in FIG. 1, which is a result of X-ray diffraction analysis showing monoclinic crystal after heat treatment of hafnium oxide film. .

In addition to stabilization of this high temperature phase, one more notable point in FIG. 3 is that the orientation of orientation is first changed within the same tetragonal phase. In the case of sample A, the preferred orientation of the (111) direction was shown, whereas from sample B, the preferred orientation of the (002) direction was started. However, in case of sample D, not only tetragonal phase but also monoclinic phase began to appear.

Experimental Example 2 Measurement of Dielectric Constant Change of Hafnium-Aluminum Metal Oxide

The dielectric constant was measured by using a capacitance-voltage (CV) analyzer (Keithley590) before the heat treatment of the hafnium-aluminum metal oxide film prepared in Example 1 and after heat treatment at 700 ° C. for 60 seconds in a nitrogen atmosphere. Is shown in FIG. 4.

Referring to FIG. 4, the sample A showing the tetragonal phase with preferred orientation in the (111) direction showed a dielectric constant of 28.5, which is an increase in the dielectric constant of 21 of the hafnium oxide film having a monoclinic phase.

In the case of samples B and C showing tetragonal phases having preferred orientation in the (002) direction, the dielectric constants increased to 47, which is more than twice the dielectric constant of the monoclinic hafnium oxide film. However, the dielectric constant decreased again from Sample D, which showed not only a tetragonal but also a monoclinic.

Experimental Example 3 Measurement of Leakage Current Change of Hafnium-Aluminum Metal Oxide

Figure 1 shows the results of measuring the leakage current before heat treatment of the hafnium-aluminum metal oxide film prepared in Example 1 and after heat treatment at 700 ° C. for 60 seconds in a nitrogen atmosphere using a leak current analyzer (HP4145B). 5 is shown.

Referring to FIG. 5, the hafnium-aluminum oxide film before the heat treatment showed an amorphous phase and exhibited a lower leakage current value than the hafnium-aluminum oxide film showing the crystalline phase after the heat treatment. In addition, the hafnium-aluminum oxide film showed a lower leakage current value than the single hafnium oxide film even after the heat treatment.

It can be seen from the above that the high dielectric constant metal oxide film according to the present invention has crystallographic and electrical properties suitable for semiconductor devices and electrical and electronic system devices.

As described above, according to the present invention, when a small amount of metal elements having a valence smaller than those of the metal elements constituting the metal oxide film are periodically added to the high dielectric constant metal oxide film whose dielectric constant changes according to the crystal phase, The crystal phase can be stabilized, and by controlling the relative amount of the metal element to be periodically added in small amounts, there is an effect that a higher permittivity can be obtained by first changing the orientation in the same crystal phase.

In addition, the semiconductor device including the high dielectric constant metal oxide film manufactured by the method according to the present invention has an advantage of having excellent electrical characteristics such as low equivalent oxide film thickness and low leakage current.

Claims (23)

Equation 1 including a high dielectric constant metal oxide film whose dielectric constant varies according to the crystal phase and crystallographic orientation, a crystal phase having a high dielectric constant, and a metal oxide film which is periodically added at 1 to 10% of the total metal oxide film weight in order to stabilize the preferred orientation High dielectric constant metal oxide film represented by: [Formula 1] (A _x O _y ) _m- (B _w O _z ) _n In the above formula, A is a metal element constituting a high-k dielectric metal oxide film whose dielectric constant varies depending on the crystal phase and crystallographic orientation, and is one or two selected from the group consisting of hafnium (Hf) and tantalum (Ta), B is one or more metal elements forming a metal oxide film which is repeatedly added at 1 to 10% of the total metal oxide film weight in order to stabilize the crystal phase having a high dielectric constant and preferential orientation, Al, Y, La, Fe, Ga, At least one selected from the group consisting of Er, Sc, Pr, Nd, Ce, Ca, Mg, and Sr, O means oxygen, x, y, w and z are each independently determined according to the type of metal element of A and B, m and n are 1 to 10% of the total weight of the metal oxide film periodically to stabilize the high dielectric constant metal oxide film (A _x O _y ) whose dielectric constant varies according to the crystal phase and crystallographic orientation, and the crystal phase having high dielectric constant and preferred orientation. The mixing ratio of the metal oxide film (B _w O _z ) added repeatedly is m + n = 100 mol%. delete delete delete The high dielectric metal oxide film according to claim 1, wherein the metal oxide film represented by Chemical Formula 1 has a thickness of 20 to 2000 kPa. The high dielectric constant metal oxide film of claim 1, wherein the dielectric constant of the metal oxide film represented by Chemical Formula 1 is 10 to 70. delete According to claim 1, wherein the structure of the metal oxide film represented by the formula (1), The high dielectric constant metal oxide film whose dielectric constant changes according to the crystal phase and crystallographic orientation is known, and the metal phase is periodically added at 1 to 10% of the total metal oxide film weight in order to stabilize the preferred phase and crystal phase having a high dielectric constant on the matrix. An oxide film is inserted in the form of particles; High dielectric constant metal oxide film whose dielectric constant varies according to crystal phase and crystallographic orientation, and crystal phase having high dielectric constant and metal oxide film which is repeatedly added at 1 to 10% of the total metal oxide film weight in order to stabilize preferential orientation are not distinguished from each other. Completely mixed with; Or 5 to 60 kW of metal oxide film whose dielectric constant varies according to the crystal phase and crystallographic orientation, and the metal oxide film that is repeatedly added at 1 to 10% of the total metal oxide film weight periodically to stabilize the crystal phase having high dielectric constant and preferential orientation. A high dielectric constant metal oxide film, characterized in that the laminated structure repeated in the thickness of. (a). In order to stabilize the crystalline phase having a high dielectric constant and preferential orientation, the step of injecting one or more metal precursors constituting the metal oxide film is added to the substrate periodically and oxidized to 1 to 10% by weight of the total metal oxide film, and adsorbing on the substrate Forming a metal oxide film which is repeatedly added in an amount of 1 to 10% by weight of the total metal oxide film periodically to stabilize the crystal phase having high dielectric constant and preferential orientation; (b). A high dielectric constant metal oxide film having a dielectric constant varying in accordance with a crystal phase and crystallographic orientation, comprising the step of injecting and oxidizing at least one metal precursor forming a high dielectric constant metal oxide film having a dielectric constant varying according to a crystalline phase and a crystallographic orientation. Forming; And        (c). Method of manufacturing a high dielectric constant metal oxide film represented by the formula (1) comprising the step of depositing the metal oxide film formed in step (a) and the metal oxide film formed in step (b) by vacuum deposition method: [Formula 1] (A _x O _y ) _m- (B _w O _z ) _n Wherein A is at least one metal element constituting a high dielectric constant metal oxide film whose dielectric constant varies depending on the crystal phase and crystallographic orientation, and is one or two selected from the group consisting of hafnium (Hf) and tantalum (Ta). , B is one or more metal elements forming a metal oxide film which is repeatedly added at 1 to 10% by weight of the total metal oxide film periodically to stabilize the crystal phase having a high dielectric constant and preferential orientation, Al, Y, La, Fe, Ga, Selected from the group consisting of Er, Sc, Pr, Nd, Ce, Ca, Mg, and Sr, O means oxygen, x, y, w and z are each independently determined according to the type of the metal element of A and B, m and n are 1 to 10% of the total weight of the metal oxide film periodically to stabilize the high dielectric constant metal oxide film (A _x O _y ) whose dielectric constant varies according to the crystal phase and crystallographic orientation, and the crystal phase having high dielectric constant and preferred orientation. The mixing ratio of the metal oxide film (B _w O _z ) added repeatedly is m + n = 100 mol%. 10. The method of claim 9, wherein the metal precursor of step (a) or (b) is an inorganic compound containing a metal element. The method of claim 10, wherein the metal precursor of step (a) is TMA (Tri methyl aluminum; Al (CH ₃ ) ₃ ). The method of claim 10, wherein the metal precursor of step (b) is TEMAHf (Tetrakis ethyl methyl amino hafnium; Hf [N (CH ₃ ) (C ₂ H ₅ )] ₄ ) Preparation of a high dielectric constant metal oxide film, characterized in that Way. The method of claim 9, wherein the substrate of step (a) or (b) is Si, SiO ₂ , TiN, Pt, Ru, RuO ₂ , Ru / RuO ₂ , Ir, IrO ₂ And an inorganic substrate or a plastic substrate selected from the group consisting of Ir / IrO ₂ . 10. The chemical vapor deposition method of claim 9, wherein the vacuum deposition in step (c) comprises physical vapor deposition (PVD) including sputtering and electron beam vapor deposition, and atomic layer deposition, plasma atomic layer deposition, and the like. A method of manufacturing a high dielectric constant metal oxide film, characterized in that it is selected from the group consisting of CVD. The method of manufacturing a high dielectric constant metal oxide film according to claim 9 or 14, wherein the oxidant used in the vacuum deposition method contains oxygen. The method of manufacturing a high dielectric constant metal oxide film according to claim 15, wherein the oxidant used in the vacuum deposition method is oxygen plasma. The method of manufacturing a high dielectric constant metal oxide film according to claim 9, further comprising the step of obtaining a crystalline film by heat treatment after step (c). 18. The method of manufacturing a high dielectric constant metal oxide film according to claim 17, wherein the heat treatment temperature is 400 to 3,000 ° C. 18. The method of claim 17, wherein the heat treatment atmosphere is a neutral atmosphere selected from the group consisting of N ₂ , Ar and He or an oxidizing atmosphere selected from the group consisting of O ₂ , H ₂ O, NO and N ₂ O. Method for producing a high dielectric constant metal oxide film. 18. The method of manufacturing a high dielectric constant metal oxide film according to claim 17, wherein the heat treatment time is 1 second to 1 hour. A device comprising a high dielectric constant metal oxide film according to any one of claims 1, 5, 6, and 8. 22. A device in accordance with claim 21 wherein the device is a semiconductor device or an electrical and electronic system device. 23. The device of claim 22, wherein the semiconductor device or the electrical and electronic system device comprises a gate oxide film of a transistor, a capacitor oxide film of a volatile memory, a tunnel of a nonvolatile memory or a controlled oxide film.

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