TWI775516B - Method for making transition metal chalcogenide films - Google Patents

Abstract

A method for fabricating a transition metal chalcogenide thin film, comprising the following steps: providing a thin film growth device, the thin film growth device comprising a primary furnace tube, a plasma generating device arranged downstream of the secondary furnace tube, and a a main furnace tube downstream of the slurry generating device and communicated with the secondary furnace tube; a substrate and a first precursor containing a transition metal are arranged in the main furnace tube, and a second precursor containing a chalcogen is arranged in the main furnace tube in this furnace tube. In the main furnace tube and the secondary furnace tube with an atmosphere of a working gas, the main furnace tube and the secondary furnace tube are sequentially heated to the working temperature of the first precursor and the second precursor, and the The plasma generating device generates plasma in the main furnace tube, so that the first precursor can be ionized by the plasma, so that the second precursor and the first precursor are co-deposited on the substrate, so as to A transition metal chalcogenide thin film is formed on the substrate.

Description

Method for making transition metal chalcogenide films

The present invention relates to a method for producing a thin film, in particular to a method for producing a transition metal chalcogenide thin film.

Tungsten trioxide is a transition metal oxide semiconductor material with narrow energy band width (2.6~3.0 eV), good photocatalytic properties in the visible light range, and tungsten atoms have different oxidation states (commonly W ⁴⁺ , W ⁵⁺ and W ⁶⁺ ), which make it have broad application prospects in the fields of gas sensing and electrochromic.

Conventionally, when forming transition metal chalcogenide films such as tungsten disulfide (WS ₂ ), sulfur (S) and tungsten trioxide (WO ₃ ) are often heated by chemical vapor deposition to deposit them on a silicon substrate However, the tungsten disulfide (WS ₂ ) films formed in this way have poor surface morphology uniformity and limited film area size, resulting in poorer properties when subsequently applied to components.

Therefore, the object of the present invention is to provide a method for producing a transition metal chalcogenide thin film.

Therefore, the method for fabricating the transition metal chalcogenide thin film of the present invention first provides a thin film growth device, the thin film growth device includes a primary furnace tube, a plasma generating device arranged downstream of the secondary furnace tube, and a A main furnace tube downstream of the slurry generating device and in communication with the secondary furnace tube.

Next, a substrate and a first precursor containing a transition metal are arranged in the main furnace tube, and a second precursor containing a chalcogen element is arranged in the secondary furnace tube.

Finally, in the main furnace tube and the secondary furnace tube with an atmosphere of a working gas, the main furnace tube and the secondary furnace tube are sequentially heated to the working temperature of the first precursor and the second precursor, and Let the plasma generating device generate plasma in the main furnace tube, so that the first precursor can be ionized by the plasma, so that the second precursor and the first precursor are co-deposited on the substrate , to form a transition metal chalcogenide film on the substrate.

The effect of the present invention is that the first precursor containing transition metal can be ionized by the plasma generated by the plasma generating device as an aid, so as to enhance the activity of the first precursor and expand the deposition range , reducing the growth temperature, thereby depositing a flat and uniform transition metal chalcogenide film on the substrate.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are designated by the same reference numerals.

Referring to FIGS. 1 and 2 , the fabrication method of the transition metal chalcogenide film of the present invention includes a providing step 21 , a setting step 22 , a ventilation step 23 , a heating step 24 , a plasma generating step 25 , and a forming step 26.

The providing step 21 is to first provide a thin film growth device 3 for growing the transition metal chalcogenide thin film by chemical vapor deposition of the plasma-assisted hot-wall horizontal furnace tube. The thin film growth apparatus 3 includes a primary furnace tube 31 , a plasma generating device 32 arranged downstream of the secondary furnace tube 31 , and a main furnace tube arranged downstream of the plasma generating device 32 and communicated with the secondary furnace tube 31 33.

Specifically, the secondary furnace tube 31 has a secondary furnace wall 311 defining a primary chamber 310 and a secondary heating device 312 surrounding the secondary furnace wall 311 , and the primary furnace tube 33 has a secondary furnace wall 311 defining a primary chamber 310 The main furnace wall 331 of the chamber 330, and a main heating device 332 surrounding the main furnace wall 331, and making the secondary chamber 310 and the main chamber 330 communicate with each other, the plasma generating device 32 is arranged around the secondary furnace between the tube 31 and the furnace wall of the main furnace wall 331 to generate plasma in the chamber space between the secondary chamber 310 and the main chamber 330 .

It is worth mentioning that the growth device 3 in this embodiment is a plasma-assisted chemical vapor deposition of a hot-walled horizontal furnace tube, so it belongs to a horizontal thin film growth mechanism, has a more uniform heating area, and can simultaneously grow many a test piece.

In the setting step 22 , a substrate 4 and a first precursor 5 containing transition metals are set in the main furnace tube 33 , and a chalcogen-containing precursor 6 is set in the secondary furnace tube 31 . In this embodiment, the substrate 4 is disposed downstream of the first precursor 5 , that is, the first precursor 5 is disposed between the plasma generating device 32 and the substrate 4 .

The substrate 4 suitable for this embodiment is not particularly limited, and a conductive substrate or an insulating substrate can be directly selected. Therefore, the substrate 4 suitable for this embodiment can be a highly oriented pyrolytic graphite substrate (HOPG) substrate, arsenic A gallium substrate, a conductive substrate such as a silicon substrate, or an insulating substrate such as a gallium nitride substrate, a silicon carbide substrate, a silicon dioxide substrate, or a sapphire substrate can be selected. In this embodiment, the substrate 4 is selected from a sapphire substrate. For example, the first precursor 5 can be selected from transition metal oxides such as tungsten trioxide (WO ₃ ), molybdenum trioxide (MoO ₃ ), etc., and selected from molybdenum hexacarbonyl (Mo(CO) ₆ ) , tungsten _hexacarbonyl (W(CO) _{6 )} ...etc A metal precursor is sufficient, and the second precursor 6 is selected from chalcogens such as sulfur, selenium, or tellurium, or is selected from methyl mercaptan (CH ₄ S), dimethyl sulfide (C ₂ H ₆ S), methyl selenol (CH ₄ Se), ethyl selenol (C ₂ H ₆ Se), methyl tellurium (CH ₄ Te), or ethyl tellurium (C ₂ H ₆ Te)… etc. contain chalcogens compound of elements. In this embodiment, the first precursor 5 is selected from tungsten trioxide (WO ₃ ), and the second precursor 6 is selected from sulfur (S) as an example for illustration.

Next, the ventilation step 23 is performed, first the main furnace tube 33 and the secondary furnace tube 31 are evacuated, and then the working gas is introduced into the secondary chamber 310, and the air flow is sent from the secondary furnace tube 31 to the main furnace The pipe 33 flows. Preferably, a suction device (not shown) can be installed at the end of the main furnace pipe 33 to allow the working gas to flow smoothly to the main furnace pipe 33 . In this embodiment, the working gas is selected from a mixed gas of argon (Ar) and hydrogen (H ₂ ) as an example for illustration, but it is not limited to this, and a general inert gas or a gas that can be used as a carrier gas can also be used be usable.

The heating step 24 is to sequentially heat the main furnace tube 33 and the secondary furnace tube 31 in the main furnace tube 33 and the secondary furnace tube 31 with a working gas atmosphere to the first precursor 5 and the second precursor the operating temperature of object 6. Since the first precursor 5 in this embodiment is selected from tungsten trioxide (WO ₃ ), and the second precursor 6 is selected from sulfur (S), for example, the working temperature for heating the main furnace tube 33 is between At 700°C to 1050°C, the working temperature for heating the secondary furnace tube 31 ranges from 110°C to 300°C. It should be noted that, in the heating step 24, the main furnace tube 33 and the secondary furnace tube 31 are preferably heated to the working temperature of the set material at the same time. Therefore, the main furnace tube 33 is heated to a certain temperature first. , and reheat the secondary furnace tube 31 .

The plasma generating step 25 is to turn on the plasma generating device 32 before the heating step 24 is heated to the working temperature, and allow the plasma to move toward the main furnace tube 33 through the airflow direction of the working gas, so that the The first precursor 5 can be ionized by the plasma. It should be noted that the timing of turning on the plasma generating device 32 is not particularly limited, as long as the first precursor 5 can be ionized by the plasma, and the conditions (such as pressure) for generating the plasma are also not particularly limited. Limit, as long as the plasma can be generated.

In the forming step 26 , the second precursor 6 , which can move to the main chamber 330 with the working gas after heating, is co-deposited on the substrate 4 together with the ionized first precursor 5 . A transition metal chalcogenide film is formed thereon. It should be noted that, in this embodiment, a film that completely covers the surface of the substrate 4 is deposited on the substrate 4 , but it is not limited to this, and it can also be deposited only on a part of the surface of the substrate 4 , then let the thin film and the substrate 4 together form a flake form.

Referring to FIG. 3 and FIG. 4 , FIG. 3 and FIG. 4 respectively show the image diagrams of two transition metal chalcogenide films produced by the conventional chemical vapor deposition process and the production method of this embodiment. The surface morphology of the thin film can be seen from the images in FIGS. 3 and 4 . In this embodiment, the plasma generated by the plasma generating device 32 is used as an aid, so that the first precursor 5 can pass through the plasma. Ionization is performed to expand the deposition range, thereby depositing a flat and uniform transition metal chalcogenide film on the substrate 4 (as shown in FIG. 4 ).

To sum up, the method for fabricating the transition metal chalcogenide thin film of the present invention is to directly ionize the first precursor 5 by directly ionizing the plasma generated by the plasma generating device 32 to enhance the first precursor 5 Therefore, the purpose of the present invention can indeed be achieved by increasing the deposition range and reducing the growth temperature, so that a flat and uniform transition metal chalcogenide film can be deposited on the substrate 4 .

However, the above are only examples of the present invention, and should not limit the scope of implementation of the present invention. Any simple equivalent changes and modifications made according to the scope of the patent application of the present invention and the contents of the patent specification are still included in the scope of the present invention. within the scope of the invention patent.

21: Provide steps

22: Setup steps

23: Ventilation step

24: Heating step

25: Plasma generation step

26: Forming step

3: Thin film growth equipment

31: Secondary furnace tube

310: Secondary Volume Room

311: Secondary furnace wall

312: Secondary heating device

32: Plasma generation device

33: Main furnace tube

330: Main room

331: Main Furnace Wall

332: Main heating device

4: Substrate

5: First Precursor

6: Second Precursor

Other features and effects of the present invention will be clearly presented in the embodiments with reference to the drawings, wherein: FIG. 1 is a schematic flow diagram illustrating a production flow of an embodiment of a method for producing a transition metal chalcogenide thin film of the present invention; FIG. 2 is a schematic diagram of a device illustrating a thin film growth device used in this embodiment of the present invention; FIG. 3 is an optical microscope image diagram illustrating an image diagram of a transition metal chalcogenide thin film fabricated in a conventional manner; and FIG. 4 is an optical microscope image diagram illustrating the image diagram of the transition metal chalcogenide thin film produced by the manufacturing method of this embodiment.

3: Thin film growth equipment

31: Secondary furnace tube

310: Secondary Volume Room

311: Secondary furnace wall

312: Secondary heating device

32: Plasma generation device

33: Main furnace tube

330: Main room

331: Main Furnace Wall

332: Main heating device

4: Substrate

5: First Precursor

6: Second Precursor

Claims (10)

A method for fabricating a transition metal chalcogenide thin film, comprising: providing a thin film growth device, the thin film growth device comprising a primary furnace tube, a plasma generating device arranged downstream of the secondary furnace tube, and a plasma generating device arranged on the downstream side of the secondary furnace tube. A main furnace tube downstream of the device and communicated with the secondary furnace tube; a substrate and a first precursor containing a transition metal are arranged in the main furnace tube, and a second precursor containing a chalcogen element is arranged in the main furnace tube In the secondary furnace tube; and in the primary furnace tube and the secondary furnace tube with a working gas atmosphere, sequentially heating the primary furnace tube and the secondary furnace tube to the work of the first precursor and the second precursor temperature, and let the plasma generating device generate plasma in the main furnace tube, so that the first precursor can be ionized by the plasma, so that the second precursor and the first precursor are co-deposited on the on the substrate to form a transition metal chalcogenide thin film on the substrate. The method for producing a transition metal chalcogenide thin film according to claim 1, wherein the substrate is disposed downstream of the first precursor. The method for producing a transition metal chalcogenide film according to claim 1, wherein the main furnace tube and the secondary furnace tube are evacuated, and then the working gas is introduced to make the gas flow from the secondary furnace tube to the main furnace tube flow and turn on the plasma generating device to generate plasma moving towards the main furnace tube. The method for producing a transition metal chalcogenide thin film according to claim 1, wherein the first precursor is selected from tungsten trioxide, and the second precursor is selected from sulfur, so as to form a composition of tungsten disulfide on the substrate of the transition metal chalcogenide films. The method for producing a transition metal chalcogenide thin film according to claim 1, wherein the working gas is selected from a mixed gas of argon and hydrogen or an inert gas. The method for producing a transition metal chalcogenide film according to claim 4, wherein the working temperature of heating the main furnace tube is between 700°C and 1050°C, and the working temperature of heating the secondary furnace tube is between 110°C and 300°C . The method for producing a transition metal chalcogenide thin film according to claim 1, wherein the second precursor is selected from compounds containing chalcogen elements, and the first precursor is selected from compounds containing transition metals. The method for producing a transition metal chalcogenide thin film according to claim 1, wherein the first precursor is selected from transition metal oxides or transition metal organic compounds. The method for producing a transition metal chalcogenide thin film according to claim 1, wherein the substrate is selected from a conductive substrate or an insulating substrate. The method for producing a transition metal chalcogenide thin film according to claim 9, wherein the conductive substrate is selected from a highly oriented pyrolytic graphite substrate, a gallium arsenide substrate, or a silicon substrate, and the insulating substrate is selected from a gallium nitride substrate, a gallium arsenide substrate, and a silicon substrate. Silicon carbide substrate, silicon dioxide substrate, or sapphire substrate.

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