Organometallic precursor compound for vapor deposition for forming oxide thin film and method for manufacturing same

Abstract

An organometallic compound, which enables thin-film deposition through vapor deposition, and particularly to a Co or Fe precursor, which is suitable for use in atomic layer deposition or chemical vapor deposition, and a method of preparing the same.

Claims

1. An organometallic compound represented by Chemical Formula 1 below: ##STR00003## in Chemical Formula 1, M is Co or Fe, R.sub.1, R.sub.2, R.sub.4 and R.sub.5 are each independently a substituted or unsubstituted C1-C4 linear or branched, saturated or unsaturated alkyl group, an isomer thereof or Si(R.sub.6R.sub.7R.sub.8), R.sub.6 to R.sub.8 are each independently a substituted or unsubstituted C1-C4 linear or branched, saturated or unsaturated alkyl group or an isomer thereof, and R.sub.3 is hydrogen, a substituted or unsubstituted C1-C4 linear or branched, saturated or unsaturated alkyl group or an isomer thereof.

2. The organometallic compound of claim 1, wherein, in Chemical Formula 1, R.sub.1 and R.sub.2 are .sup.iPr, R.sub.3 is Me or Et, and R.sub.4 and R.sub.5 are each independently .sup.tBu or SiMe.sub.3, wherein Me represents a methyl group, Et represents an ethyl group, .sup.iPr represents an iso-propyl group, .sup.tBu represents a tert-butyl group, and SiMe.sub.3 represents Si(CH.sub.3).sub.3.

3. The organometallic compound of claim 1, wherein, in Chemical Formula 1, R.sub.1 is .sup.tBu, R.sub.2 is Et, R.sub.3 is Me or Et, and R.sub.4 and R.sub.5 are each independently .sup.tBu or SiMe.sub.3, wherein Me represents a methyl group, Et represents an ethyl group, .sup.iPr represents an iso-propyl group, .sup.tBu represents a tert-butyl group, and SiMe.sub.3 represents Si(CH.sub.3).sub.3.

4. An organometallic precursor for vapor deposition, comprising the organometallic compound of claim 1.

5. The organometallic precursor of claim 4, wherein the vapor deposition includes atomic layer deposition or chemical vapor deposition.

6. A method of manufacturing a thin film, comprising: subjecting the organometallic precursor of claim 4 to physical/chemical adsorption on a substrate, purging the organometallic precursor, which is not adsorbed, with an inert gas, and introducing a reaction gas.

7. The method of claim 6, wherein the reaction gas includes at least one selected from among hydrogen peroxide (H.sub.2O.sub.2), water vapor (H.sub.2O), oxygen (O.sub.2), and ozone (O.sub.3).

8. The method of claim 6, wherein the thin film is a metal oxide thin film.

9. The method of claim 8, wherein the metal oxide thin film is a perovskite thin film.

Description

DETAILED DESCRIPTION

(1) Hereinafter, embodiments and examples of the present invention will be described in detail so that those skilled in the art can easily carry out the present invention with reference to the accompanying drawings. However, the present invention may be embodied in many different forms, and is not limited to the embodiments and examples described herein. In order to clearly illustrate the present invention in the drawings, parts not related to the description are omitted.

(2) As used herein, it is to be understood that the formation of any member “on” another member includes not only the case where the member is in contact with the other member but also the case where a further member is present between the two members.

(3) As used herein, when any part “includes” any element, it is to be understood that it may further include other elements as well, rather than excluding such other elements, unless otherwise stated.

(4) As used herein, the “step that” or “step of ˜” does not mean the “step for ˜”.

(5) As used herein, Me represents a methyl group, Et represents an ethyl group, .sup.iPr represents an iso-propyl group, .sup.tBu represents a tert-butyl group, and SiMe.sub.3 represents Si(CH.sub.3).sub.3.

(6) An aspect of the present invention pertains to an organometallic compound represented by Chemical Formula 1 below:

(7) ##STR00002## in Chemical Formula 1, M is Co or Fe, R.sub.1, R.sub.2, R.sub.4 and R.sub.5 are each independently a substituted or unsubstituted C1-C4 linear or branched, saturated or unsaturated alkyl group, an isomer thereof or Si(R.sub.6R.sub.7R.sub.8), preferably, R.sub.4 and R.sub.5 are each independently .sup.tBu or SiMe.sub.3, R.sub.6 to R.sub.8 are each independently a substituted or unsubstituted C1-C4 linear or branched, saturated or unsaturated alkyl group or an isomer thereof, and R.sub.3 is hydrogen, a substituted or unsubstituted C1-C4 linear or branched, saturated or unsaturated alkyl group or an isomer thereof.

(8) Another aspect of the present invention pertains to an organometallic precursor for vapor deposition comprising the organometallic compound of Chemical Formula 1.

(9) According to an embodiment of the present invention, in Chemical Formula 1, R.sub.1 and R.sub.2 may be .sup.iPr, R.sub.3 may be Me or Et, and R.sub.4 and R.sub.5 may each independently be .sup.tBu or SiMe.sub.3. Here, Me represents a methyl group, Et represents an ethyl group, .sup.iPr represents an iso-propyl group, .sup.tBu represents a tert-butyl group, and SiMe.sub.3 represents Si(CH.sub.3).sub.3.

(10) According to an embodiment of the present invention, in Chemical Formula 1, R.sub.1 may be .sup.tBu, R.sub.2 may be Et, R.sub.3 may be Me or Et, and R.sub.4 and R.sub.5 may each independently be .sup.tBu or SiMe.sub.3. Here, Me represents a methyl group, Et represents an ethyl group, .sup.iPr represents an iso-propyl group, .sup.tBu represents a tert-butyl group, and SiMe.sub.3 represents Si(CH.sub.3).sub.3.

(11) Still another aspect of the present invention pertains to an organometallic precursor for vapor deposition comprising an organometallic compound prepared based on the present invention.

(12) In an embodiment of the present invention, the vapor deposition may include, but is not limited to, atomic layer deposition (ALD) or chemical vapor deposition (CVD).

(13) Yet another aspect of the present invention pertains to a method of manufacturing a thin film by depositing an organometallic precursor for vapor deposition, the method comprising subjecting an organometallic precursor for vapor deposition of Chemical Formula 1 to physical/chemical adsorption on a substrate, purging the organometallic precursor for vapor deposition, which is not adsorbed, with an inert gas, and introducing a reaction gas.

(14) In an embodiment of the present invention, the reaction gas may include, but is not limited to, at least one selected from among hydrogen peroxide (H.sub.2O.sub.2), water vapor (H.sub.2O), oxygen (O.sub.2), and ozone (O.sub.3).

(15) In an embodiment of the present invention, the thin film may be a metal oxide thin film, particularly a perovskite thin film. The perovskite thin film may include, but is not limited to, a perovskite nanocrystal structure ABX.sub.3.

(16) A better understanding of the present invention will be given through the following Example and Preparation Example, which are not to be construed as limiting the present invention.

Example

(17) Preparation of Organometallic Precursor

(18) Bis[bis(trimethylsilyl)amido]iron(II) (Fe(btmsa).sub.2) (0.0320 mol, 12.05 g) and dry toluene (50 mL) were placed in a 250 mL flask and stirred, thus affording a dark brown solution. N′-tert-butyl-N-ethyl propionimidamide (Et-.sup.tBu-Et-amidine) (0.0320 mol, 5.00 g) and dry toluene (50 mL) were placed in a 100 mL flask and cooled to 0° C. with stirring. The previously prepared Fe(btmsa).sub.2 solution was slowly added to the stirred solution. When the above solution was added, white smoke was generated during the reaction and a dark brown solution resulted, which was then stirred at room temperature for 16 hr. After termination of the reaction, the solvent was removed in a vacuum, and the remaining volatile material was extracted with hexane, thus yielding [Et-.sup.tBu-Et-AMD]Fe(btmsa). The organometallic precursor Et-.sup.tBu-Et-AMD]Fe(btmsa) is a compound of Chemical Formula 1 according to the present invention, in which R.sub.1=.sup.tBu, R.sub.2=Et, R.sub.3=Et, R.sub.4=SiMe.sub.3, R.sub.5=SiMe.sub.3 and M=Fe(II).

Preparation Example

(19) Formation of Metal Oxide Thin Film

(20) The organometallic precursor [Et-.sup.tBu-Et-AMD]Fe(btmsa) including the organometallic compound of Chemical Formula 1 prepared in the above Example was deposited in a thin film using an ALD device. The substrate used therefor was a p-type Si(100) wafer having a resistance of 0.02.Math.cm. Before the deposition, the p-type Si wafer was washed through ultrasonic treatment with each of acetone, ethanol, and deionized (DI) water for 10 min each. The oxide thin film naturally formed on the Si wafer was immersed in a solution of 10% HF (HF:H.sub.2O=1:9) for 10 sec and then taken out therefrom. The Si wafer washed with HF was immediately transferred into an ALD chamber. The organometallic precursor used therefor was a Fe-containing precursor, but a Co-containing precursor may be used. The reaction temperature was maintained at 85° C. The organometallic precursor of Chemical Formula 1 (15 sec), Ar (30 sec), 03 (5 sec/8 sec/10 sec) and Ar (30 sec) were sequentially supplied, and the flow rate of argon (Ar) for purging was 100 sccm. Used as the reaction gas, ozone (03) was allowed to flow at a rate of 30 sccm. Each reaction gas was introduced by adjusting the on/off operation of a pneumatic valve, and the pressure of the reactor was set to 1 torr at a deposition temperature ranging from 260° C. to 340° C.

(21) The organometallic precursor for vapor deposition was prepared as in the above Example, and the oxide thin film was formed by depositing the organometallic precursor for vapor deposition as in the above Preparation Example. The oxide thin film thus obtained is a metal oxide thin film, particularly a perovskite thin film.

(22) A thin film resulting from depositing a perovskite material having an ABX.sub.3 structure has superior physical properties, such as those pertaining to ferroelectric and superconducting phenomena. In the perovskite material, A and B may be cations having different sizes, and X may be oxygen (O.sub.2). The ratio of A, B and X elements is finely adjusted, thus enabling the formation of a perovskite thin film having a size on the scale of ones of nanometers.

(23) The organometallic precursor [Et-.sup.tBu-Et-AMD]Fe(btmsa) prepared in Example of the prevent invention and the metal oxide thin film formed in Preparation Example through ALD using the same have the following advantages. Specifically, the organometallic precursor [Et-.sup.tBu-Et-AMD]Fe(btmsa) is a liquid at room temperature, thus ensuring processing convenience and uniform volatility and assuring an improvement in film quality by virtue of thermal stability in the processing range. Furthermore, a high deposition rate may be realized due to high reactivity with the reaction gas (H.sub.2O.sub.2, H.sub.2O, O.sub.2 or O.sub.3) during the processing.

(24) The scope of the invention is represented by the claims below rather than the aforementioned detailed description, and all changes or modified forms that are capable of being derived from the meaning, range, and equivalent concepts of the appended claims should be construed as being included in the scope of the present invention.