KR20220026269A - Deposition method of molybdenum-containing thin films and molybdenum-containing thin films manufactured thereby - Google Patents

Abstract

The present invention relates to a molybdenum-containing thin film manufacturing method comprising the following steps of: a) cleaning and surface treating a substrate; b) maintaining a substrate temperature below 500 ℃ by mounting the substrate in a chamber; and c) depositing a molybdenum-containing thin film on the substrate of step b) using a molybdenum-containing compound represented by the following chemical formula 1 under a transport gas and a reaction gas. The chemical formula 1 is represented by. An objective of the present invention is to provide the method for manufacturing a high-purity molybdenum-containing thin film using the molybdenum compound for depositing a semiconductor thin film which has thermal stability and is liquid at a room temperature.

Description

A method for producing a molybdenum-containing thin film and a molybdenum-containing thin film produced thereby.

The present invention relates to a method for producing a molybdenum-containing thin film and to a molybdenum-containing thin film prepared according to the method, and more particularly, to a molybdenum-containing thin film of high purity using a molybdenum precursor liquid at room temperature and thermal stability. It relates to a method for producing a lybdenum-containing thin film and to a molybdenum-containing thin film manufactured according to the manufacturing method.

Molybdenum (Mo) is applied as an electrode, diffusion barrier, gas sensor, and catalyst material in various semiconductor and display metal processes. In particular, molybdenum-containing thin films replace graphene materials. As a two-dimensional semiconductor material to be used, research on its application is progressing rapidly and broadly.

In addition, molybdenum has excellent chemical and thermal stability, high electrical conductivity and low electrical resistivity (ρ = 0.57×10 ^-5 Ω cm at bulk). Research and development for molybdenum or molybdenum-containing thin films are being conducted in various fields as it is in the spotlight as a material that meets the needs.

Molybdenum chloride (MoCl ₅ ) is a representative molybdenum compound used to form a molybdenum-containing thin film. However, according to Thin Solid Films, 166, 149 (1988), disadvantages such as low deposition rate, large amount of chlorine and film contamination by hydrogen chloride are reported. There are no downsides.

Also, Chem. Vap. Imido compounds such as Mo(NtBu) ₂ (NiPr ₂ ) ₂ reported in Deposition (2008) 14, 71 are known, but they have relatively poor thermal stability and π between the molybdenum central metal and nitrogen by imido ligands. - Due to the high stability of binding, the decomposition of the ligand in the process does not occur cleanly, so carbon contamination is very severe. and US Pat. No. 4,431,708 and J. de Phys. A molybdenum-containing thin film produced by vapor deposition using a Mo(CO) ₆ compound with a relatively high vapor pressure reported in IV 2(C2), 865 has been reported, but it is a solid compound at room temperature and has uneven vaporization characteristics, Low thermal stability and the possibility of particle issues are also high.

Accordingly, the problem to be solved by the present invention is to provide a thermally stable compound for depositing a liquid molybdenum thin film that does not contain halogen, etc., which is highly likely to cause adverse effects on semiconductors and display devices.

The present invention was devised in view of the prior art as described above, and an object of the present invention is to provide a method for manufacturing a high-purity molybdenum-containing thin film using a molybdenum compound for depositing a semiconductor thin film that is liquid at room temperature and thermal stability.

In addition, an object of the present invention is to provide a molybdenum-containing thin film prepared by the above manufacturing method.

The method for manufacturing a molybdenum-containing thin film of the present invention for achieving the above object is a method for manufacturing a high-purity molybdenum-containing thin film using a molybdenum compound for semiconductor thin film deposition having excellent thermal stability and high vapor pressure. , the manufacturing method comprises the steps of: a) cleaning and surface treatment of the substrate; b) installing the substrate in a chamber to maintain the substrate temperature at less than 500°C; c) a molybdenum-containing compound under a transport gas and a reaction gas Depositing a molybdenum-containing thin film on the substrate of step b) using

In this case, the substrate temperature in step b) may be 200°C or higher to less than 500°C.

In addition, the molybdenum compound may be represented by the following formula (1).

[Formula 1]

In addition, the deposition may include plasma-enhanced chemical vapor deposition, thermal chemical vapor deposition, plasma-enhanced ALD (PEALD), or thermal atomic layer deposition (Thermal). ALD) may be performed by any one of the processes.

In addition, the transport gas is nitrogen, argon, helium or a mixture thereof, and the reaction gas is O ₂ , O ₃ , H ₂ O, NO, NO ₂ , N ₂ O, H ₂ O ₂ , H ₂ , NH ₃ , alkylamines, hydrazine derivatives, SiH ₄ , Si ₂ H ₆ , BH ₃ , B ₂ H ₆ , amine-borane complex, GeH ₄ , PH ₃ or a mixed gas thereof.

According to the method for producing a molybdenum-containing thin film according to the present invention, a high-quality thin film can be manufactured through a process using a molybdenum compound that is liquid at room temperature, has high volatility and has excellent thermal stability.

In addition, since the thin film is deposited using a molybdenum compound having high thermal stability and vapor pressure and excellent volatility, it is possible to achieve the effect of manufacturing a high-purity molybdenum-containing thin film.

1 is a result of ¹ H-NMR analysis of (methylcyclopentadienyl) (dicarbonyl) (nitrosyl) molybdenum prepared in Example 1.
2 is a result of measuring the vapor pressure curve of (methylcyclopentadienyl) (dicarbonyl) (nitrosyl) molybdenum prepared in Example 1.
3 is a thermogravimetric analysis (TGA) result of (methylcyclopentadienyl)(dicarbonyl)(nitrosyl)molybdenum prepared in Example 1. FIG.
4 is a scanning electron microscope (SEM) image of observing the thickness of the (methylcyclopentadienyl)(dicarbonyl)(nitrosyl)molybdenum-containing thin film prepared in Example 2. FIG.
5 is a diagram showing the deposition behavior of the thin film prepared in Example 2 according to (methylcyclopentadienyl)(dicarbonyl)(nitrosyl)molybdenum implantation time.
6 is an X-ray photoelectron spectroscopy (XPS) image of a thin film containing (methylcyclopentadienyl)(dicarbonyl)(nitrosyl)molybdenum prepared in Example 2. FIG.

Hereinafter, the present invention will be described in more detail. The terms or words used in the present specification and claims should not be construed as being limited to their ordinary or dictionary meanings, and the inventor may properly define the concept of the term in order to best describe his invention. Based on the principle that there is, it should be interpreted as meaning and concept consistent with the technical idea of the present invention.

The method for manufacturing a thin film according to the present invention is a method for manufacturing a high-purity molybdenum-containing thin film using a molybdenum compound for semiconductor thin film deposition having excellent thermal stability and high vapor pressure, the manufacturing method comprising:

a) cleaning and surface treatment of the substrate;

b) maintaining the substrate temperature below 500° C. by mounting the substrate in a chamber;

c) depositing a molybdenum-containing thin film on the substrate of step b) using a molybdenum-containing compound under a transport gas and a reactive gas.

The molybdenum-containing thin film of the present invention is manufactured by forming a molybdenum-containing thin film on a substrate using a molybdenum precursor compound at a temperature of less than 500 ° C. A thin film may be provided.

The substrate temperature in step b) may preferably be 200° C. or more to less than 500° C., and more preferably 300° C. or more to 400° C. or less in order to produce a molybdenum-containing thin film of more excellent durability and high purity.

The molybdenum precursor compound according to an embodiment is represented by the following Chemical Formula 1.

[Formula 1]

Deposition according to an embodiment is possible as long as it is a method used in the technical field to which the present invention pertains. For example, plasma enhanced chemical vapor deposition, thermal chemical vapor deposition, plasma It may be performed by any one deposition method of plasma enhanced atomic layer deposition or thermal atomic layer deposition.

In addition, as the transport gas, nitrogen, argon, helium, or a mixed gas thereof may be used, and preferably, argon, helium or a mixed gas thereof may be used. In addition, as a reactive gas, O ₂ , O ₃ , H ₂ O, NO, NO ₂ , N ₂ O, H ₂ O ₂ , H ₂ , NH ₃ , alkylamine, hydrazine derivative, SiH ₄ , Si ₂ H ₆ , BH ₃ , B ₂ H ₆ , amine-borane complex, GeH ₄ , PH ₃ or a mixture thereof may be used, preferably hydrogen (H ₂ ), ammonia (NH ₃ ), oxygen (O ₂ ), ozone ( O ₃ ) or a mixed gas thereof.

Hereinafter, the manufacturing method of the molybdenum-containing thin film of the present invention will be described in detail.

First, a) cleaning and surface treatment of the substrate. The substrate according to an embodiment may be any substrate used in the technical field of the present invention, but may preferably be a silicon-containing substrate. The cleaning of the substrate is not limited, but the organic material and the oxide film are washed on the silicon-containing substrate by washing with a solution in which an acid and hydrogen peroxide are mixed and washing with hydrofluoric acid.

Next, b) mounting the substrate in the deposition equipment chamber to maintain the substrate temperature below 500° C., by mounting the silicon-containing substrate in the chamber to maintain the substrate temperature below 500° C. to prepare for deposition.

Next, c) depositing a molybdenum-containing thin film on the substrate of step b) using a molybdenum compound under a transport gas and a reaction gas under a transport gas and a reaction gas at a process pressure of 0.01 to 1 Torr in the chamber A molybdenum-containing thin film is deposited on the silicon-containing substrate maintained at less than 500° C. using a molybdenum precursor compound. At this time, the process pressure in the chamber is carried out at 0.01 to 1 Torr, the transport gas is 50 to 300 sccm, and the reaction gas is 100 to 1000 sccm, a method commonly used in the art, preferably plasma enhanced chemical vapor deposition (Plasma enhanced). It is deposited using a deposition method such as chemical vapor deposition, thermal chemical vapor deposition, plasma enhanced atomic layer deposition, or thermal atomic layer deposition.

Hereinafter, the present invention will be described in more detail through examples. Prior to this, the terms or words used in the present specification and claims should not be construed as being limited to conventional or dictionary meanings, and the inventor should properly understand the concept of the term in order to best describe his invention. Based on the principle that it can be defined, it should be interpreted as meaning and concept consistent with the technical idea of the present invention.

Accordingly, the embodiments described in this specification and the configurations shown in the drawings are only the most preferred embodiment of the present invention and do not represent all the technical spirit of the present invention, so at the time of this application, they can be replaced It should be understood that there are various equivalents and variations.

Example 1. Synthesis of (methylcyclopentadienyl)(dicarbonyl)(nitrosyl)molybdenum

57.05 g of lithium methylcyclopentadienide and 600 ml of tetrahydrofuran were injected into a flame-dried 1000 ml Schlenk flask under a nitrogen atmosphere.

After cooling the reactor internal temperature to 0 ℃, 132 g of molybdenum carbonyl was added for about 15 minutes, and the reactor internal temperature was maintained at 0 to 5 ℃.

Upon completion of the addition, the temperature was raised to 65° C. and the mixture was stirred under reflux for 18 hours. After cooling the reactor internal temperature to 25°C, 107.2 g of N-methyl-N-nitroso-p-toluenesulfonamide was slowly added at room temperature, followed by stirring for 1 hour.

After completion of the reaction, the solvent and by-products were removed under reduced pressure, and the remaining product was purified under reduced pressure (88° C./0.48 Torr) to obtain 84.8 g of (methylcyclopentadienyl)(dicarbonyl)(nitrosyl)molybdenum. did (Yield: 65%)

Example 2. Preparation of Molybdenum-Containing Thin Film

In order to prepare a molybdenum-containing thin film, the silicon substrate was first washed with a mixed solution of sulfuric acid and hydrogen peroxide, and then washed with a hydrofluoric acid solution for the second time.

Thereafter, the compound of Example 1 (Formula 1) was deposited on the substrate as a molybdenum-containing precursor compound in a vapor state at a silicon substrate temperature of 300° C. by thermal atomic layer deposition to deposit a molybdenum-containing thin film. was formed. Hydrogen (H ₂ ) was used as the reaction gas, and argon (Ar), an inert gas, was used to transport the molybdenum-containing precursor in a vapor state and to purge residues. Table 1 below shows deposition methods for specific molybdenum-containing thin films.

Comparative Example 1. Preparation of Molybdenum-Containing Thin Film

Molybdenum-containing thin film was formed by depositing a compound of Mo(CO) ₆ on the substrate under the same conditions as in Example 2 except that the substrate temperature was set to 150°C. (See Table 1 below.)

The specific resistance, thickness, and composition of the molybdenum-containing thin film prepared in Example 1 and Comparative Example 1 are shown in Table 2 below.

Board
temperature
(℃) precursor
injection time
(sec) Fudge Reaction gas injection (H2) Fudge deposition
number
(cycle) flux
(sccm) hour
(sec) flux
(sccm) hour
(sec) flux
(sccm) hour
(sec) Example 1 300 10 1200 30 150 15 1200 30 300 Comparative Example 1 150 10 1200 30 150 15 1200 30 300

Thin film composition (%) resistivity
μΩ cm thickness
(Å) Mo C O Example 1 75.91 13.06 11.03 47 120 Comparative Example 1 61.23 11.51 27.1 412 180

As shown in Table 2, the molybdenum-containing thin film deposited in Example 1 compared to the molybdenum-containing thin film deposited in Comparative Example 1 had an excellent thin film composition with significantly less oxygen and high molybdenum content, and the specific resistance was also It was confirmed that it was significantly lower.

Although the present invention has been described with reference to preferred embodiments as described above, it is not limited to the above embodiments and various modifications are made by those skilled in the art within the scope of not departing from the spirit of the present invention. and can be changed Such modifications and variations are intended to fall within the scope of the present invention and the appended claims.

Claims (5)

a) cleaning and surface treatment of the substrate;
b) maintaining the substrate temperature below 500° C. by mounting the substrate in a chamber;
c) depositing a molybdenum-containing thin film on the substrate of step b) using a molybdenum-containing compound represented by the following formula (1) under a transport gas and a reaction gas;
Molybdenum-containing thin film manufacturing method comprising a.

[Formula 1]

The method according to claim 1,
The substrate temperature of step b) is a molybdenum-containing thin film manufacturing method, characterized in that 200 ℃ or more to less than 500 ℃.
The method according to claim 1,
The thin film deposition method includes plasma enhanced chemical vapor deposition, thermal chemical vapor deposition, plasma enhanced atomic layer deposition, or thermal atomic layer deposition. deposition), characterized in that it is carried out by any one method of manufacturing a molybdenum-containing thin film.
The method according to claim 1,
The transport gas is nitrogen (N ₂ ), helium (H ₂ ), argon (Ar) or a mixture thereof,
The reaction gas is O ₂ , O ₃ , H ₂ O, NO, NO ₂ , N ₂ O, H ₂ O ₂ , H ₂ , NH ₃ , alkylamine, hydrazine derivative, SiH ₄ , Si ₂ H ₆ , BH ₃ , B ₂ H ₆ , amine-borane complex, GeH ₄ , PH ₃ or a method for producing a molybdenum-containing thin film, characterized in that a mixed gas thereof.
The method according to claim 1,
The deposition is a molybdenum-containing thin film manufacturing method, characterized in that performed at 0.01 Torr to 1.0 Torr.

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