KR20080064259A - Thin film deposition method comprising improved metal precursor feeding and purging step - Google Patents

Abstract

A thin film deposition method comprising an improved metal precursor feeding and a purging step is provided to reduce the time required for obtaining a thin film with a desired thickness by improving a deposition speed in a short process time. A thin film deposition method comprising an improved metal precursor feeding and a purging step includes the steps of: subsequently and repeatedly performing the step of providing the metal precursor and the purging step(S1) two times; and providing and purging a reaction gas in order to divide the metal precursor(S2). A total time required for performing the step of providing the metal precursor is the same as that required for providing the metal precursor of the corresponding steps of providing and purging the metal precursor, and a total time required for performing the step of purging the metal precursor is the same as that required for purging the metal precursor of the corresponding steps of providing and purging the metal precursor.

Description

Thin film deposition method comprising improved metal precursor feeding and purging step

1 is a schematic cross-sectional view of a thin film deposition apparatus capable of performing a thin film deposition method according to the present invention.

2 is a graph showing the growth rate of the thin film according to the metal precursor supply time.

3 is a flowchart of a thin film deposition method according to the present invention.

4A to 4D are schematic views of a metal precursor supply and purge step in the thin film deposition method according to the present invention.

5A is a gas pulsing diagram of a conventional ALD method.

5B and 5C are gas pulsing diagrams of the thin film deposition method according to the present invention.

6A and 6B are graphs showing growth rates according to Hf supply time when a thin film is deposited by a conventional ALD method as shown in FIG. 5A.

Figure 6c is a graph showing the growth rate according to the Hf supply time when the thin film is deposited by the conventional ALD method and according to the present invention.

<Explanation of symbols for the main parts of the drawings>

10 ... Reactor 11 ... Showerhead

12 ... wafer block 12a ... heater

13 ... pumping baffle 14 ... gas curtain block

20 ... Gas Supply 100 ... Thin Film Deposition

The present invention relates to a method of depositing a thin film by the ALD method using a metal precursor, and more particularly, to a method of depositing a thin film at a high speed by increasing the semiconductor substrate coverage of the metal precursor in a short time.

Silicon oxide film (SiO ₂ ) and silicon nitride film (SiNx) used in semiconductor devices have been used as gate oxide and capacitor dielectric films for a long time due to their excellent thermal stability, insulation, dielectric property, and chemical resistance. However, since the dielectric constants of the silicon oxide film and the silicon nitride film are relatively low at 3.5 and 7.0, respectively, the thickness of the film must be made very thin in order to secure sufficient capacitance as the size of the semiconductor device is reduced. However, a problem arises in that the leakage current increases exponentially as the thickness of the silicon oxide film and the silicon nitride film decreases, and thus the silicon oxide film and the silicon nitride film cannot be used in a semiconductor device of high density.

As semiconductor devices have been highly integrated, scaling of gate oxide films has also been required. Even if the thickness thereof becomes thin due to scaling, it is required to maintain excellent electrical characteristics. However, as the thickness of the gate oxide becomes thinner, leakage current due to direct tunneling increases, thereby increasing standby current, disturbing logic states, and degrading time dependent dielectric breakdown (TDDB) characteristics. There is. Conventional gate oxide films, such as silicon oxide films, suffer from leakage current and lack of reliability as their thickness is reduced to less than 20 mA.

In order to solve this problem, as a material having a high dielectric constant to replace the silicon oxide film and silicon nitride film, tantalum oxide film (Ta ₂ O ₅ ), titanium oxide film (TiO ₂ ), zirconium oxide film (ZrO ₂ ), hafnium oxide film (HfO ₂ ) and a method using a ferroelectric BST or the like has been proposed.

In order to use the high-k material as a gate oxide film, it is necessary to deposit very thin and precisely, and to use as a capacitor dielectric film, an excellent step coverage is required. Prior deposition techniques, such as chemical vapor deposition (CVD), cannot meet the demand for progressive thin films. Although CVD processes can be dedicated to provide conformal films with advanced step coverage, CVD processes often require high process temperatures and result in incorporation of high impurity concentrations. Thus, efforts are underway to develop improved methods for depositing materials in pure form with uniform stoichiometry, thickness, conformal coverage, and the like.

In order to satisfy these conditions, a high dielectric constant material must be deposited by an ALD method using a metal precursor. In general, the ALD method repeats a cycle of supplying and purging a metal precursor and supplying and purging a reaction gas for decomposition of the metal precursor, but has a disadvantage in that the deposition rate of the thin film is slower than that of the CVD method.

An object of the present invention is to provide a method for depositing a thin film at a high speed.

One aspect of the thin film deposition method according to the present invention for achieving the above technical problem, the metal precursor supply and purge step of repeating the process consisting of the step of supplying and purging the metal precursor two or more times in succession; And a reaction gas supply and purge step of supplying and purging the reaction gas for decomposition of the metal precursor. The cycle is repeated one or more times to deposit a thin film.

Here, the total execution time of the step of supplying the metal precursor during the metal precursor supply and purge step is the same as the metal precursor supply time during the corresponding (conventional) metal precursor supply and purge step, and during the metal precursor supply and purge step The total run time of purging the metal precursor is equal to the purge time during the corresponding (conventional) metal precursor feed and purge step.

In a preferred embodiment, the one time execution time of the step of supplying the metal precursor during the metal precursor supply and purge step is 0.1-3 seconds, and the one time step of purging the metal precursor during the metal precursor supply and purge step The time is 1-30 seconds.

Another aspect of the thin film deposition method according to the present invention for achieving the technical problem, the step of supplying a metal precursor into the reactor loaded with a semiconductor substrate to chemically adsorb and physically adsorb the metal precursor on the surface of the semiconductor substrate; And exposing if there is a site capable of chemical adsorption on the surface of the semiconductor substrate by supplying an inert gas into the reactor to remove the unadsorbed metal precursor and the physically adsorbed metal precursor. Supplying and purging the metal precursor to form a chemically adsorbed metal precursor monoatomic layer on the surface of the semiconductor substrate at a high density; Supplying a reaction gas for decomposing the metal precursor into the reactor to react with the metal precursor adsorbed on the surface of the semiconductor substrate; And supplying an inert gas into the reactor to remove unreacted reactant gases and reaction byproducts, but depositing a thin film by repeating the cycle one or more times.

Various thin films can be deposited using the thin film deposition method according to the present invention. For example, oxide or nitride or oxynitride thin films of metal elements and transition metal elements, such as aluminum, titanium, zirconium, hafnium and tantalum, may be deposited using the precursors of these metals and the oxidizing and / or nitriding reaction gases according to the invention. Can be deposited by. In addition, pure metal layers such as ruthenium, copper, tantalum and other metal layers can be deposited by the thin film deposition method according to the invention using precursors of these metals and reducing or combustion reaction gases.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings. The embodiments described below may be modified in many different forms, and the scope of the present invention is not limited to the embodiments described below. The embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art. In the drawings illustrating embodiments of the present invention, like numerals in the drawings refer to like elements.

First, the thin film deposition method according to the present invention can be performed using a thin film deposition apparatus as shown in FIG.

The thin film deposition apparatus 100 of FIG. 1 is for depositing a thin film on a semiconductor substrate w such as a silicon wafer seated on the wafer block 12 in the reactor 10.

Here, the thin film deposition apparatus 100 includes a reactor 10 through which thin film deposition is performed, and a gas supply device 20 for supplying a metal precursor, a reaction gas, and an inert gas to the reactor 10.

The reactor 10 includes a shower head 11 disposed above the inside of the shower head 11 to which metal precursors, a reactive gas and an inert gas are injected, and a wafer block disposed below the shower head 11 and on which the semiconductor substrate w is mounted. 12) and pumping baffles 13 installed on the outer periphery of the wafer block 12 for smooth and uniform pumping of metal precursors, reactive gases, inert gases and reaction by-products, and inert gases on the outer periphery of the shower head 11. The gas curtain block 14 is included.

The metal precursor may be supplied into the reactor 10 at a flow rate of 10 to 1500 sccm in a bubbled form by Ar or He, which is an inert gas, and may be a liquid delivery system (LDS) or a vaporization system (vaporization system). May be fed into the reactor 10 via.

A heater 12a is built in the wafer block 12, and the heater 12a heats the semiconductor substrate w in a range of 100 ° C. to 700 ° C. FIG. The pumping baffle 13 can ensure optimal thickness uniformity and composition of the thin film, and optimize the reaction space.

The gas curtain block 14 injects an inert gas toward the edge of the semiconductor substrate w to control the compositional change of the edge of the semiconductor substrate w, and furthermore, the inner wall of the reactor 10, specifically the pumping baffle 13, Minimize contamination by metal precursors.

In the case of depositing a thin film by a general ALD method using the thin film deposition apparatus as shown in FIG. 1, as shown in FIG. 2, as the execution time of the metal precursor supplying step, that is, the metal precursor supply time becomes longer, It can be seen that the growth rate of and the coverage of the metal precursor increases.

However, the growth rate increase rate of the thin film when the metal precursor supply time is moderately long compared to the growth rate increase rate of the thin film when the metal precursor supply time is relatively short (I) is small. When the metal precursor supply time is longer than a predetermined time (III), the growth rate of the thin film does not change no matter how long the time is extended. The inventors of the present invention studied to find the cause of the phenomenon, and found that the degree of chemical adsorption of the metal precursor to the semiconductor substrate is deeply related to the phenomenon. Thus, when the metal precursor supply time is short (I) is a sub-saturation step in which chemical adsorption is still in progress, and when the metal precursor supply time is moderately long (II), half saturation with about half the chemical adsorption proceeds. In the (semi-saturation) step, when the metal precursor supply time is more than a predetermined time (III), it was defined as the full saturation step in which all chemical adsorption is completed. In addition, it was found that the growth rate of the thin film can be increased by continuously exposing the sites capable of chemical adsorption on the semiconductor substrate before the saturation step so that the chemical adsorption is completed completely. Then, detailed conditions were investigated in detail to complete the present invention.

3 is a flowchart of a thin film deposition method according to the present invention. 4A to 4D are schematic views of a metal precursor supply and purge step in the thin film deposition method according to the present invention. Next, a method of depositing a thin film according to the present invention will be described with reference to FIGS. 3 and 4A to 4D in the following order.

First, the semiconductor substrate w on which the thin film is to be deposited is loaded into the reactor 10 of the thin film deposition apparatus 100. The temperature of the semiconductor substrate w is then preheated to a process temperature suitable for film deposition using a heater 12a provided in the reactor 10. At this time, the preheating of the semiconductor substrate w is performed simultaneously with the exhaust from the reactor 10, and the pressure in the reactor 10 is maintained at 10 Torr or less. When the semiconductor substrate w is raised to a desired process temperature, thin film deposition is started.

Referring to step t1, which is a sub-step of step s1 of FIG. 3, the metal precursor is supplied into the reactor 10 while the semiconductor substrate w is loaded inside the reactor 10 to supply the metal precursor to the surface of the semiconductor substrate w. Metal precursors are chemisorbed and physically adsorbed. For example, Hf precursor is supplied for 0.1-3 seconds to chemically adsorb and physically adsorb the semiconductor substrate w. For example, HfCl ₄ , Hf (OtBu) ₄ , Hf (N (C ₂ H ₅ ) ₂ ) ₄ , TDMAHf (tetra dimethyl amino hafnium, Hf [N (CH ₃ ) ₂ ] ₄ ), TDEAHf ( tetra diethyl amino hafnium, Hf [N (C ₂ H ₅ ) ₂ ] ₄ ), and TEMAHf (tetra ethyl methyl amino hafnium, Hf [N (C ₂ H ₅ ) CH ₃ ] ₄ ) It is supplied into the reactor 10 at a flow rate of 10 to 1500 sccm in a bubbled form by Ar or He which is an inert gas. Alternatively, the source stock solution is diluted with a solvent such as n-butyl acetate, n-hexane, tetrahydrofuran, ethylcyclohexane, etc., and passed through a liquid supply device or a vaporizer to use a source changed into a gaseous state.

4A shows a metal precursor (A) chemisorbed on a surface of a semiconductor substrate (w), a metal precursor (B) physically adsorbed thereon, and an unadsorbed metal precursor (C) thereon. It can be seen that there are relatively many chemically adsorptive empty sites on the surface of the semiconductor substrate w. Since the metal precursor supply is conventionally maintained in such a state, the metal precursor is likely to be physically adsorbed onto the physically adsorbed metal precursor B again without being occupied by the chemically adsorbable sites occluded by the physically adsorbed metal precursor B. Accordingly, the density of the metal precursor chemisorption layer is low, and as shown in FIG. 2, when the metal precursor supply time is longer than a predetermined time, the chemical adsorption is saturated and the thin film growth rate is no longer increased. In the present invention, such a problem is found, so that the chemical adsorption of the metal precursor is maximized at the beginning of the process to increase the semiconductor substrate coverage, thereby improving the thin film growth rate.

Next, referring to step t2 which is a sub-step of step s1 of FIG. 3, an inert gas is supplied into the reactor 10 to remove the unadsorbed metal precursor C and the physically adsorbed metal precursor B. (w) Expose a site (D) capable of chemical adsorption on the surface. This is a purge step, preferably performed by supplying an unreactive gas such as Ar or N ₂ to 10 to 1000 sccm, more preferably 100 to 1000 sccm. It can also be done by pumping excess gas using a vacuum pump. The purge time may be 1-30 seconds. FIG. 4B shows that a site D capable of chemical adsorption is exposed on the surface of the semiconductor substrate w by this purge.

The process consisting of the above sub-steps t1 and t2 is repeated two or more times in succession. That is, as shown in FIG. 4C, the metal precursor is supplied again to chemically adsorb and physically adsorb the metal precursor on the surface of the semiconductor substrate w. The chemically adsorbable site (D) exposed as shown in FIG. 4B by the sub step t2 is filled with the chemical precursor by the metal precursor in this step. On the other hand, here again, there is a metal precursor (A) chemisorbed on the surface of the semiconductor substrate (w), the metal precursor (B) and the non-adsorbed metal precursor (C) physically adsorbed thereon. Then, as shown in FIG. 4D, an inert gas is supplied to remove the unadsorbed metal precursor (C) and the physically adsorbed metal precursor (B).

4D, it can be seen that the metal precursor monoatomic layer chemically adsorbed on the surface of the semiconductor substrate w is formed at a higher density than in the case of FIG. 4B. In the present invention, by improving the metal precursor supply and purge step, if the site capable of chemical adsorption is continuously exposed and the chemical adsorption is made to increase the semiconductor substrate coverage of the metal precursor. This is more effective when the metal precursor is large in size.

Thus, the metal precursor supply and purge step s1 in FIG. 3 is completed. The total execution time of the step t1 of supplying the metal precursor during the metal precursor supply and purge step s1 is the same as the metal precursor supply time during the corresponding (conventional) metal precursor supply and purge step, and the metal precursor supply and purge The total execution time of step t2 for purging the metal precursor in step s1 is made equal to the purge time during the corresponding (conventional) metal precursor supply and purge step. For example, if the conventional metal precursor supply time is 5 seconds and the metal precursor purge time is 20 seconds, the step (t1) of supplying the metal precursor in the present invention is 1 second, and the step (t2) of purging the metal precursor is The process consisting of the step (t1) of supplying the metal precursor and the step (t2) of purging the metal precursor for 4 seconds is carried out five times in succession. In this case, the step (t1) of supplying the metal precursor is performed five times by 1 second to give a total execution time of 5 seconds, and the step (t2) of purging the metal precursor is 5 times of 4 seconds to give a total execution time of 20 seconds.

Subsequently, a reaction gas for decomposing the metal precursor is supplied into the reactor 10 and reacted with the metal precursor adsorbed on the surface of the semiconductor substrate w (step s2). For example, the reactor supplies any one selected from H ₂ O, H ₂ O ₂ , O ₂ and O ₃ . The reaction gas may be supplied in a plasma state by a remote plasma method, or may be supplied in a state in which a direct plasma is applied into the reactor 10. In this case, the applied plasma may be a low frequency of 300 to 500KHz and / or a high frequency of 13.56MHz to 21.12MHz at a power of 50 to 2000W.

Then, an inert gas is supplied into the reactor 10 to remove unreacted reaction gases and reaction by-products such as CO, CO ₂ , H ₂ O formed by the oxidation reaction (step s3).

The monolayer of HfO ₂ made of, for example, Hf-O, is formed on the surface of the semiconductor substrate w by the process consisting of steps s1 to s3. The process consisting of steps s1 to s3 is performed as one cycle, and it is determined whether a thin film having a desired thickness is deposited (step s4), and the cycle is repeated one or more times until the desired thickness is deposited.

The thin film formed by the above method is very fast in growth, and is grown in a very dense and good step coverage, and thus can be applied in various ways in the manufacturing process of highly integrated semiconductor devices. For example, the HfO ₂ film formed by the above method may be composed of a gate oxide film at the time of gate formation on a semiconductor substrate. In addition, the HfO ₂ film formed by the above method may be composed of a capacitor dielectric film when the capacitor is formed on the semiconductor substrate.

On the other hand, the embodiment is a metal precursor supply and purge step (s1) of repeating the process consisting of the step of supplying and purging one metal precursor two or more times in succession; And a reaction gas supply and purge step of supplying a reaction gas for decomposing a metal precursor (s2) and purging (s3), when depositing a thin film as one cycle, that is, an oxide of a single metal (for example, All have been described in the case of depositing HfO ₂ ), nitride, oxynitride or pure metal layer.

However, as a modification of the present invention, the step of supplying and purging the first metal precursor (eg, Hf precursor) and purging the first metal precursor (s1) is repeated two or more times in succession; A reaction gas supply and purge step of supplying a reaction gas for decomposition of the first metal precursor (s2) and purging (s3); A second metal precursor supply and purge step (s11) of repeating a process consisting of supplying and purging a second metal precursor (eg, Si precursor) two or more times in succession; And supplying and purging the reaction gas for decomposing the second metal precursor (s12) and purging (s13); depositing a multi-component thin film (for example, HfSiO or HfSiN or HfSiON) as one cycle. It is also possible. As such, any deposition method having a metal precursor supplying and purging step of repeating a process consisting of supplying and purging one kind of metal precursor two or more times will correspond to the modification of the present invention.

Experimental Example

The conventional conventional ALD method, which repeats the cycle consisting of the supply and purge of the metal precursor, the supply and purge of the reactant gas, is repeated several times and the deposition method according to the invention with the supply and purge step of the improved metal precursor.

First, FIG. 5A is a gas pulsing diagram of the conventional ALD method. Shown is the Hf precursor supply and purge step (s1 ') consisting of only supplying TEMAHf as a Hf precursor for 3 seconds (t1') and purging for 20 seconds (t2 '), and O ₃ as a reaction gas. After the completion of one cycle by performing the reaction gas supply step (s2 ') for 3 seconds and the purge step (s3') for 3 seconds, the cycle is repeated several times to deposit a thin film. In the experiment, the step (t1 ') of supplying TEMAHf as the Hf precursor was performed at different times from 0.5 seconds to 15 seconds. The step (t2 ') of purging the Hf precursor was performed at 10 seconds or 20 seconds.

5B and 5C are gas pulsing diagrams of the thin film deposition method according to the present invention.

First, FIG. 5B shows an Hf precursor supply and purge step (s1) of continuously supplying TEMAHf as an Hf precursor for 1.5 seconds (t1) and purging for 10 seconds (t2) two times in succession, and O as a reaction gas. _The reaction gas supply step (s2) for supplying ₃ for 3 seconds and the purge step (s3) for purging for 3 seconds are performed to complete one cycle. This cycle is repeated several times to deposit a thin film. The total execution time of the step (t1) of supplying the Hf precursor in the Hf precursor supply and purge step (s1) is 1.5 × 2 = 3 seconds, corresponding to the corresponding (conventional) metal precursor supply and purge step shown in FIG. 5A. It is the same as the metal precursor supply time t1 'in (s1'). In addition, the total execution time of the step (t2) of purging the Hf precursor in the Hf precursor supply and purge step (s1) is 10 × 2 = 20 seconds, and the corresponding (conventional) metal precursor supply and purge shown in FIG. 5A is provided. It is equal to the purge time t2 'during the step s1'.

Next, FIG. 5C shows an Hf precursor supply and purge step (s1), in which a step (t1) of supplying TEMAHf as an Hf precursor (t1) and a step (t2) of purging the Hf precursor for 7 seconds are repeated three times in succession, One cycle is completed by performing a reaction gas supply step s2 for supplying O ₃ as a reaction gas for 3 seconds and a purge step s3 for purging for 3 seconds. This cycle is repeated several times to deposit a thin film. The total execution time of the step (t1) of supplying the Hf precursor during the Hf precursor supply and purge step (s1) is 1 × 3 = 3 seconds, so that the corresponding (conventional) metal precursor supply and purge step shown in FIG. 5A ( It is equal to the metal precursor supply time t1 'in s1'). In addition, the total execution time of the step (t2) of purging the Hf precursor during the Hf precursor supply and purge step (s1) is 7 × 3 = 21 seconds, and the corresponding (conventional) metal precursor supply and purge shown in FIG. 5A is provided. Almost equal to the purge time t2 'during the step s1'.

FIG. 6A is a graph illustrating a growth rate according to Hf supply time (Hf precursor supply time) when a thin film is deposited by the conventional ALD method as illustrated in FIG. 5A. Here, the deposition rate per cycle is shown, and the step (t2 ') for purging the Hf precursor is set to 20 seconds.

As shown in FIG. 6A, as the time (t1 ') of supplying TEMAHf as the Hf precursor gradually increases to 3 seconds, 5 seconds, 10 seconds, and 15 seconds, the growth rate is increased. It can be seen that there is no change.

6B is a graph showing a growth rate according to Hf supply time when a thin film is deposited by a conventional ALD method as shown in FIG. 5A. Here, the deposition rate after the cycle is repeated several times, and the step (t2 ') for purging the Hf precursor is 10 seconds.

As shown in FIG. 6B, the growth rate is larger when the process temperature is 250 ° C. than when the process temperature is 300 ° C., and the time of the step (t1 ′) of supplying TEMAHf as the Hf precursor is 0,5 seconds, 1 second, 2 As the growth rate increases to seconds, 3 seconds, 4 seconds, 5 seconds, and 6 seconds, it can be seen that the growth rate is almost unchanged after only 1 second. In addition, when deposited on the trench type structure, growth rates in the center, top, bottom, left and right are slightly different.

Figure 6c is a graph showing the growth rate according to the Hf supply time when the thin film is deposited by the conventional ALD method and according to the present invention. Here, the deposition rate per cycle is shown, and the step (t2 ') for purging the Hf precursor is made 20 seconds.

As shown in Fig. 6C, the conventional case (-■-) is performed under the condition of Fig. 5A, and the first embodiment (---) is the same condition as in Fig. 5B and the second embodiment (-▲-) Is the case under the same conditions as in FIG. 5C. Example 3 (-▼-) was further divided into three times as compared to Example 2, and the step (t1) of supplying TEMAHf as the Hf precursor for 0.5 seconds (t1) and the step of purging the Hf precursor for 3 seconds (t2) were continuously performed. Performing the Hf precursor supply and purge step (s1) repeated repeatedly, the reaction gas supply step (s2) for supplying O ₃ as a reaction gas for 3 seconds and the purge step (s3) for purging for 3 seconds, s1 to s3 The cycle consists of several times to deposit a thin film. The total execution time of the step (t1) of supplying the Hf precursor during the Hf precursor supply and purge step (s1) is 0.5 × 6 = 3 seconds, so that the corresponding (conventional) metal precursor supply and purge step (shown in FIG. It is equal to the metal precursor supply time t1 'in s1'). In addition, the total execution time of the step (t2) of purging the Hf precursor during the Hf precursor supply and purge step (s1) is 3 × 6 = 18 seconds, and the corresponding (conventional) metal precursor supply and purge shown in FIG. 5A is provided. Almost equal to the purge time t2 'during the step s1'.

 In the conventional case (-■-), the growth rate increases as the time (t1 ') of supplying TEMAHf as the Hf precursor increases to 3 seconds, 5 seconds, 10 seconds, and 15 seconds, but only 10 seconds, the growth rate is increased. There is little change and it is shown that the maximum growth rate can be obtained by supplying the Hf precursor for at least 10 seconds.

In contrast, in Example 1 (-●-), Example 2 (-▲-), and Example 3 (-▼-), the time for supplying the Hf precursor was 3 seconds, and the time for supplying the Hf precursor was It can be seen that the growth rate is very fast compared to the case of 3 seconds. In particular, in the case of Example 2 (-▲-), the time for supplying the Hf precursor is 3 seconds, but the growth rate is almost the same as the time for supplying the conventional Hf precursor is 10 seconds or more. Therefore, according to the present invention, it is possible to improve the deposition rate in a short process time, significantly reducing the time for obtaining a thin film having a desired thickness as compared to the conventional ALD method, and consumes less metal precursor.

Although the detailed description of the present invention has been made, it will be apparent to those skilled in the art that various modifications may be made without departing from the scope of the present invention. The invention is only defined by the scope of the claims.

According to the present invention, the deposition rate can be improved in a short process time, and the time for obtaining a thin film having a desired thickness can be considerably reduced as compared to the conventional ALD method, thereby improving the productivity of the semiconductor device using the thin film. have.

It is also an economical method with low consumption of metal precursors. In addition, the thin film obtained according to the present invention has excellent step coverage and density and thickness uniformity of the thin film. Therefore, it is more suitable for highly integrated semiconductor devices.

Claims (4)

A metal precursor supply and purge step of repeating a process consisting of supplying and purging a metal precursor two or more times in succession; And A reaction gas supply and purge step of supplying and purging the reaction gas for decomposition of the metal precursor; Thin film deposition method, characterized in that for one cycle, by repeating the cycle one or more times to deposit a thin film. The method of claim 1, wherein the total execution time of the step of supplying the metal precursor during the metal precursor supply and purge step is the same as the metal precursor supply time during the corresponding metal precursor supply and purge step and during the metal precursor supply and purge step The total execution time of the purging the metal precursor is the same as the purge time during the corresponding metal precursor supply and purge step. The method of claim 2, wherein the one time execution time of supplying the metal precursor during the metal precursor supply and purge step is 0.1-3 seconds, and the one time operation of purging the metal precursor during the metal precursor supply and purge step is performed. Thin film deposition method, characterized in that the time is 1-30 seconds. Chemically adsorbing and physically adsorbing the metal precursor onto a surface of the semiconductor substrate by supplying a metal precursor into a reactor loaded with a semiconductor substrate; And Supplying an inert gas into the reactor to remove unadsorbed metal precursors and physically adsorbed metal precursors, thereby exposing any sites capable of chemical adsorption on the surface of the semiconductor substrate; Supplying and purging the metal precursor to form a high density metal precursor monoatomic layer chemically adsorbed on the surface of the semiconductor substrate by repeating a process consisting of two or more times in succession; Supplying a reaction gas for decomposing the metal precursor into the reactor to react with the metal precursor adsorbed on the surface of the semiconductor substrate; And Supplying an inert gas into the reactor to remove unreacted reaction gas and reaction byproducts; Thin film deposition method, characterized in that for one cycle, by repeating the cycle one or more times to deposit a thin film.

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