KR100679640B1 - Precursor for preparing 13-group metal chalcogenide in chemical vapor deposition, method threrof and thin film of chalcogenide using the precursor - Google Patents

Abstract

The present invention can be usefully used in the manufacture of a thin film of sulfur (S) and selenium (Se) compounds of group 13 (Ga, In, Tl) containing indium by chemical vapor deposition (hereinafter referred to as CVD). It relates to an organometallic compound precursor represented by the following formula (1), a method for preparing the same, and a group 13 chalcogenide compound and a mixture thereof, and more specifically, a group 13 metal and a chalcogen at a low temperature by using a single precursor of S, Se) provides a sulfide thin film having a composition of element 2: 3.

Chemical Vapor Deposition, Organometallic Compound Precursor, Chalcogen

Description

Chemical vapor deposition precursor for the preparation of chalcogenide thin film of Group 13 metals, a method for preparing the same and a chalcogenide thin film using the precursor PRECURSOR}

The present invention can be usefully used in the manufacture of a thin film of sulfur (S) and selenium (Se) compounds of group 13 (Ga, In, Tl) containing indium by chemical vapor deposition (hereinafter referred to as CVD). The present invention relates to an organometallic compound precursor represented by the following Chemical Formula 1 and a method for preparing the same, and more specifically, a composition of a Group 13 metal and a chalcogen (S, Se) element at a low temperature using a single precursor of Chemical Formula 1 below 2: A sulfide thin film is provided.

[Formula 1]

In the above formula, M (Group 13) is Ga, In and Tl, E is a chalcogen element (S, Se) and R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ are each independently C ₁ An alkyl group of ˜C ₆ and a cycloalkyl group to which R ₁ and R ₂ or R ₃ and R ₄ or R ₅ and R ₆ are linked.

Group 13 elements in the periodic table refer to aluminum (Al), gallium (Ga), indium (In), thallium (Tl), and chalcogenide (chalcogenide) refers to sulfur (S), The compounds composed of selenium (Se) and tellurium (Te) are collectively referred to. Chalcogenides are typically zinc sulfide (ZnS), cadmium sulfide (CdS), mercury sulfide (HgS), zinc selenide (ZnSe), Cadmium telluride (CdTe). The chalcogenide exhibits various semiconductor properties, and is a key material used for magneto-optical memory devices, n-type or p-type semiconductors, quantum dots, solar cells, and the like. Thin film process is under development.

In manufacturing a conventional thin film of chalcogenide, unlike other elements due to the characteristics of the chalcogenide it can be vaporized at a high temperature (Vaporization) it was possible to prepare a thin film by evaporation (evaporation) at high temperature. . However, the above-mentioned evaporation method can produce a thin film simply, while energy efficiency is low, and above all, the vapor pressure of the metal and the chalcogen element is different, and the volatilization temperature of the chalcogen element (sulfur (S) = 444.67 ° C., selenium) (Se) = 684.9 DEG C and tellurium (Te = 989.9 DEG C) are also so high that it is very difficult to produce high quality thin films of high purity so as to have a desired structure with a specific composition.

Therefore, by using a physical vapor deposition method (PVD) used in the Republic of Korea Patent Publication No. 2002-0059162 as a recent improved method for manufacturing _a thin film of chalcogenide of various compositions such as (Ge _a Bi _b Sb _c ) Te _X The manufacturing method is described, and in addition, the solution growth method using a conventional chemical method (CBD; Chemical Bath Deposition, Korean Patent No. 10-0220371, CdS thin film production) and the electrodeposition method, which is a kind of plating method using electrochemistry, U. S. Patent No. 6,036, 822, U. S. Patent No. 5, 772, 431) and the like have been reported as thin film manufacturing techniques of various chalcogenides.

In addition, in the manufacture of thin films such as CIS (CuInSe ₂ ), a new material used as a solar cell light absorption layer in chalcogenides, a method for manufacturing thin films in an easier process by improving the evaporation method using volatility at a high temperature. Many studies have been conducted, such as Vapor Evaporation Deposition and Close Spaced Sublimation, which can be simultaneously evaporated under vacuum to obtain thinning. (US Pat. No. 4,523,051, US Pat. No. 5,045,409, USA Patent 6,444,043)

As mentioned above, the thin film manufacturing method can be classified into two types, and physical methods using phase deformation, such as physical vapor deposition (PVD) and vacuum evaporation, are accompanied by chemical reactions such as solution growth and electrodeposition. It can be distinguished by chemical methods. However, in both methods, various process condition factors are required to provide a chalcogenide thin film having a specific composition ratio. For example, complex factors such as matching the vapor pressure and maintaining the concentration ratio of the solution are required. In addition, the above-mentioned thinning method has advantages in that the manufacturing cost is relatively low and the manufacturing equipment is simple, but it is difficult to control the composition due to the characteristics of the chalcogenide, and it is difficult to see the reproducibility of the thickness and uniformity of the thin film. In particular, in the vacuum evaporation method, most chalcogen elements have a high volatilization point and must be deposited at high temperature and high pressure. Since the volatilization points of the respective elements are also different, the difficulty of depositing a desired composition greatly increases. In addition, there are many disadvantages such as the need for a post-process of heat treatment at a high temperature for replenishment of loss elements and phase formation after deposition (US Pat. No. 6,323,417).

In addition, the thin film manufacturing process using the solution growth method is limited to a method limited to CdS, and also the disadvantage of the wet method as a process of growing a thin film by soaking a base material in a chemical solution remains a problem to be overcome.

Therefore, many studies have been conducted to solve the above problems, and a representative method is chemical vapor deposition (CVD). This chemical vapor deposition (CVD) method is a uniform and selective deposition of the produced thin film, and if a precursor having a constant composition can be provided reproducibly through a simple process of a single composition of the metal electrode, metal oxide, etc. It is widely used in the semiconductor manufacturing process. However, the chemical vapor deposition method requires a precursor having a sublimation characteristic while achieving a specific composition ratio required the most important metal and chalcogen element. In this study, TiS ₂ thin films were prepared in US Pat. No. 5,112,650. In the US Pat. Nos. 5,837,320, thiocarboxylate groups were formed on divalent metals (Ca, Sr, Ba, Zn, Cd, Pb, Ga, In, Sb, Bi). Introduced a precursor for the production of metal sulfide (Metal-S) thin film. However, the existing organometallic precursor is limited to the manufacture of a thin film of metal sulfide and is limited to a specific use.

To solve this problem, the organometallic single precursor for chemical vapor deposition of chalcogenides, which is composed of all components in a specific composition ratio, has a specific composition ratio of specific metals and chalcogen elements (S, Se, Te). It should be able to form and have proper volatilization characteristics at low temperature, relatively low decomposition temperature is required, and it is relatively heat stable during vaporization process so that it can easily form chalcogenide phase after decomposition. Recently, such a study has reported a single organometallic precursor (US Pat. No. 5,300,320) in which a chalcogen element is introduced using a tertiary butyl group to gallium (Ga), aluminum (Al), and indium (In) metal. In the preparation of chalcogenide thin films requiring various components and compositions, there are still many limitations in the selection of metals. In the preparation of chalcogenides made of multiple metals, sulfur (S) or selenium (S), which is a highly volatile element such as evaporation, is still used. It is a situation that has a problem that Se) lacks in composition. Only recently, as a new chalcogenide precursor compound in Korean Patent Application No. 10-2003-0023385 reported by this research group, [R ₂ M (??-ER ₁ )] ₂ (where M is In and Ga, E A new group 13 chalcogenide precursor has been reported which is a chalcogen element (S, Se); and R _1, R ₂ , are each independently an alkyl group of C _1-6; as precursors for the Group 12 chalcogenide films in 0,113,209, and _{M (E 2 CNR 1 R 2} ) 2 ( where M is Zn, Cd, Hg, E is a chalcogen element (S, Se), and; R _1, R ₂ has reported an organometallic compound in the form of an alkyl group). It is only characterized by providing a chalcogenide thin film having a composition of 1: 1 with a chalcogen element for a Group 12 or Group 13 metal.

Accordingly, the present inventors have studied a variety of metal chalcogenide precursor compounds consisting of a group 13 metal and chalcogen elements in a constant composition ratio and capable of chemical vapor deposition at a low temperature in order to solve the above problems, the structure of formula 1 The precursors were synthesized to find a thin film of chalcogenide having a composition of M ₂ E ₃ (M: metal, E: chalcogen element) and a chalcogen element having a 2: 3 composition. Completed.

Accordingly, an object of the present invention is to provide a precursor of Chemical Formula 1, which is useful in the manufacture of a thin film of a chalcide compound having a composition of a Group 13 metal (Ga, In, Tl) and a calogen element 2: 2 by chemical vapor deposition. Another object of the present invention is to provide a method for producing the precursor.

In order to achieve the above object, the precursor for producing a group 13 chalcide thin film by the chemical vapor deposition method of the present invention is characterized in that the organometallic compound represented by the following formula (1).

[Formula 1]

In the above formula, M (Group 13) is Ga, In, Tl, E is a chalcogen element (S, Se), R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ are each independently C An alkyl group of ₁ to C ₆ and a cycloalkyl group to which R ₁ and R ₂ or R ₃ and R ₄ or R ₅ and R ₆ are linked.

Hereinafter, the present invention will be described in more detail.

The precursor represented by Chemical Formula 1 of the present invention can be synthesized by two methods as follows. Briefly, this carbon disulfonic Olympiad (CS _2, carbon disulfide or carbon di-selenide (CSe _2, a precursor represented by the formula (I) mentioned above using a _{[MCl 3] carbon diselenide),} 2 primary amine, and a metal chloride Where M is Group 13 metal, Ga, In, Tl, and E means S, Se.

If this is described in more detail, it can be represented by a reaction scheme.

[Scheme]

Synthesis method using NaOH, CE ₂ , secondary amine and metal chloride (MCl ₃ )

In the above scheme, M (Group 13) is Ga, In, Tl and E is a chalcogen element (S, Se), R _1, R _2, each independently an alkyl group of C ₁ ~ C ₆ And R _1, And R ₂ represents a linked cycloalkyl group.

In detail, 80 ml of solvent methanol and 0.3 mol of sodium hydroxide are added to a 200 ml shrink flask and completely dissolved, followed by cooling to 0 ° C. To this, slowly add 0.3 moles of secondary amine and CE ₂ , each using a double vacuum line and cannula. 0.1 mol of Group 13 metal chloride [MCl ₃ ] dissolved in a small amount of distilled water is added dropwise to the mixed solution. Precipitation begins to occur, and after about 1 hour, a precipitate is obtained using a glass filter. The solvent was removed completely and recrystallized to give a reaction.

Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited only to these examples.

Example 1 Synthesis of Indium (diethyldithiocarbamate) ₃

80 ml of solvent methanol and 0.3 mol of sodium hydroxide were added to a 200 ml shrink flask, and the mixture was completely dissolved and cooled to 0 ° C. To this was slowly added 0.3 moles of diethylamine and 0.3 moles of CS ₂ using a double vacuum line and a cannula. To this mixed solution was added dropwise a solution of 0.1 mol of indium chloride completely dissolved in a small amount of distilled water. Precipitation begins to occur, and after about 1 hour, a precipitate is obtained using a glass filter. The solvent was removed completely and recrystallized to give a reaction.

Example 2 Synthesis of Indium (ethylbutyldithiocarbamate) ₃

Indium (ethylbutyldithiocarbamate) ₃ was synthesized in the same manner as in Example 1, except that ethylbutylamine was used instead of diethylamine.

Example 3 Synthesis of Indium (2-ethylpiperidinedithiocarbamate) ₃

Indium (2-ethylpiperidinedithiocarbamate) ₃ was synthesized in the same manner as in Example 1, except that 2-ethylpiperidine was used instead of diethylamine.

Example 4 Synthesis of Gallium (Diethyldithiocarbamate) ₃

80 ml of solvent methanol and 0.3 mol of sodium hydroxide were added to a 200 ml shrink flask, and the mixture was completely dissolved and cooled to 0 ° C. To this was slowly added 0.3 moles of diethylamine and 0.3 moles of CS ₂ using a double vacuum line and a cannula. To this mixed solution was added dropwise a solution of 0.1 mol of gallium chloride completely dissolved in a small amount of distilled water. Precipitation begins to occur, and after about 1 hour, a precipitate is obtained using a glass filter. The solvent was removed completely and recrystallized to give a reaction.

Example 5 Synthesis of Gallium (Ethylbutyldithiocarbamate) ₃

Gallium (ethylbutyldithiocarbamate) ₃ was synthesized in the same manner as in Example 4, except that ethylbutylamine was used instead of diethylamine.

Example 6 Synthesis of Gallium (2-ethylpiperidinedithiocarbamate) ₃

Gallium (2-ethylpiperidinedithiocarbamate) ₃ was synthesized in the same manner as in Example 4, except that 2-ethylpiperidine was used instead of diethylamine.

Example 7 Synthesis of Gallium (Dipropyldithiocarbamate) ₃

80 ml of solvent methanol and 0.3 mol of sodium hydroxide were added to a 200 ml shrink flask, and the mixture was completely dissolved and cooled to 0 ° C. To this, slowly add 0.3 moles of dipropylamine and 0.3 moles of CS ₂ using a double vacuum line and a cannula. To this mixture is added dropwise a solution of 0.1 mol of gallium chloride completely dissolved in a small amount of distilled water. Precipitation begins to occur, and after about 1 hour, a precipitate is obtained using a glass filter. The solvent was removed completely and recrystallized to give a reaction.

Example 8 Synthesis of Thallium (Ethylbutyldithiocarbamate) ₃

80 ml of solvent methanol and 0.3 mol of sodium hydroxide were added to a 200 ml shrink flask, and the mixture was completely dissolved and cooled to 0 ° C. To this was slowly added 0.3 moles of ethylbutylamine and 0.3 moles of CS ₂ using a double vacuum line and a cannula. To this mixed solution, a solution of 0.1 mol of thallium chloride completely dissolved in a small amount of distilled water is added drop by drop. Precipitation begins to occur, and after about 1 hour, a precipitate is obtained using a glass filter. The solvent was removed completely and recrystallized to give a reaction.

Example 9 Synthesis of Gallium (Diethyl Diselenocarbamate) ₃

80 ml of solvent methanol and 0.3 mol of sodium hydroxide were added to a 200 ml shrink flask, and the mixture was completely dissolved and cooled to 0 ° C. To this was slowly added 0.3 moles of diethylamine and 0.3 moles of CSe ₂ using a double vacuum line and a cannula. To this mixed solution was added dropwise a solution of 0.1 mol of gallium chloride completely dissolved in a small amount of distilled water. Precipitation begins to occur, and after about 1 hour, a precipitate is obtained using a glass filter. The solvent was removed completely and recrystallized to give a reaction.

Example 10 Synthesis of Indium (EthylbutylDiselenenocarbamate) ₃

80 ml of solvent methanol and 0.3 mol of sodium hydroxide were added to a 200 ml shrink flask, and the mixture was completely dissolved and cooled to 0 ° C. To this was slowly added 0.3 moles of ethylbutylamine and 0.3 moles of CSe ₂ using a double vacuum line and a cannula. To this mixed solution was added dropwise a solution of 0.1 mol of indium chloride completely dissolved in a small amount of distilled water. Precipitation begins to occur, and after about 1 hour, a precipitate is obtained using a glass filter. The solvent was removed completely and recrystallized to give a reaction.

Example 11 Synthesis of Indium (2-ethylpiperidine disselenocarbamate) ₃

Indium (2-ethylpiperidinediselenocarbamate) ₃ was synthesized in the same manner as in Example 10, except that 2-ethylpiperidine was used instead of ethylbutylamine.

The reactants synthesized in Examples 1 to 11 were identified through NMR (nuclear magnetic resonance analysis), FT-IR (infrared spectroscopy), MASS (mass spectrometry) and elemental analysis, and summarized in Table 1 below. It was.

TABLE 1

In the table above,

[Manufacture example 1-8]

Using the precursor synthesized in Examples 1 to 11 above, a thin film was manufactured by the CVD vacuum deposition apparatus as shown in FIG. 1. In the CVD deposition apparatus, the bubbler temperature of the precursor was maintained at 150 to 180 ° C under an argon atmosphere, and the vapor deposition substrate was deposited while changing the substrate temperature to 350 to 490 ° C. At this time, the CVD chamber was reduced by 5 mtorr, and a thin film having a thickness of 150 to 1000 nm was prepared over 2 hours. In each case, the prepared thin film was confirmed to form a high purity chalcogenide single phase thin film without impurities through X-Ray Diffraction (XRD), and the grain size of the chalcogen having a grain size of 300-700 nm through an electron microscope It was confirmed that a cargo thin film was prepared. In addition, the melting point and decomposition temperature of the precursor at atmospheric pressure were measured through a thermal analyzer analysis. The results are shown in Table 2 below, and the phase change seen as a sublimation between the melting point and the decomposition temperature was confirmed. Based on this, the temperature of the precursor was deposited at around 150 to 180 ° C.

TABLE 2

From here,

Note 1) Air and thermal stability: Maintained more than 2 days at the temperature higher than the melting point

Note 2) Melting Point, Decomposition Temperature: Thermal Analyzer Analysis

As can be seen in Table 2, the Group 13 metal chalcogenide precursor synthesized with the new skeleton of Examples 1 to 8 has a volatilization characteristic at low temperature, and the typical characteristics of the precursor requiring a relatively low decomposition temperature are well represented. It was confirmed to meet. In particular, as the composition ratio of the most important group 13 metal and chalcogenide element can be known through X-ray photoelectron spectroscopy (XPS), the composition ratio of the metal / chalcogen element is 0.65 to 0.67, which shows that the thin film was manufactured. . Therefore, the precursor of the new skeleton prepared in the present invention is excellent for the preparation of chalcogenide (chalcogenide, M ₂ E ₃ M: Group 13 metal, E: chalcogen element) thin film having a metal and chalcogen composition ratio of 2: 3. It was confirmed that it is a precursor.

As described above, the present invention provides a synthesis method for the precursor as a previous step for the manufacture of thin films of various applications, such as light absorption thin film layer, quantum dots, LED thin film of the solar cell using the chemical vapor deposition method, Group 13 chalcogenide precursor is a single-phase high purity chalcogenide (chalcogenide, M ₂ E ₃ M: group 13 metal, E: chalcogen element) having a composition of group 13 metal and chalcogen element by chemical vapor deposition. ) Can provide a thin film.

Claims (6)

Chemical vapor deposition precursor for producing a chalcogenide (chalcogeneide) thin film of a Group 13 metal, characterized by having an organometallic compound structure represented by the formula (1). Formula 1

Wherein M is a Group 13 metal selected from the group consisting of Ga, In and Tl, E is a chalcogen element of S or Se, and R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ Are each independently selected from an ethyl group or a butyl group, wherein R ₁ and R ₂ are asymmetrical structures, R ₃ and R ₄ are asymmetrical structures, and R ₅ and R ₆ are asymmetrical structures.) Method for producing a chemical vapor deposition precursor for producing a chalcogenide thin film of the Group 13 metal represented by the formula (1) of claim 1, characterized in that carried out by the following scheme.

(In the above formula, M is a Group 13 metal selected from the group consisting of Ga, In, and Tl, E is a chalcogen element of S or Se, and R ₁ and R ₂ are each independently an ethyl group or a butyl group.) The Group 13 metal according to claim 1, wherein the Group 13 chalcogenide compound is any one selected from the group consisting of gallium sulfide, indium sulfide, thallium sulfide, gallium selenide, indium selenide, and thallium selenide. Chemical vapor deposition precursor for the production of chalcogenide thin film. delete delete A group 13 metal selected from the group consisting of Ga, In and Tl, which is prepared by chemical vapor deposition using a chemical vapor deposition precursor for preparing a chalcogenide thin film of a group 13 metal represented by Chemical Formula 1 of claim 1: A chalcogenide thin film having a composition ratio of 2: 3 between chalcogen elements of S or Se.