KR20210105178A - MANUFACTURING METHOD AND APPARATUS OF SiC-BASED HETEROSTRUCTURE - Google Patents

Abstract

The present invention relates to a method of forming a silicon carbide heterostructure and an apparatus thereof. The method includes: a powder drying step of drying silicon carbide powder having an average particle size of no less than 50 to no more than 200 nanometers; an aerosol preparation step of locating the silicon carbide powder dried in the powder drying step in an aerosol chamber; an aerosol formation step of forming an aerosol by supplying feeding gas from a feeding gas storage tank to the aerosol chamber; and a heterostructure formation step of forming a heterostructure between a substrate and a silicon carbide film by spraying the aerosol to the substrate. Through the steps, a dense silicon carbide film can be formed in a low temperature process. Moreover, the apparatus includes: an aerosol chamber storing silicon carbide powder having an average particle size of no less than 50 to no more than 200 nanometers therein, and forming an aerosol by mixing feeding gas with the silicon carbide powder; a feeding gas supply pipe connected to the bottom of the aerosol chamber and having a flow path formed therein; a feeding gas storage tank supplying the feeding gas through the feeding gas supply pipe; a mass flowrate controller mounted on the feeding gas pipe and controlling the flowrate of the feeding gas; an aerosol pipe connected to the top of the aerosol chamber and having a flow path formed therein; a nozzle connected with the aerosol pipe and spraying the aerosol; a deposition chamber having a space, in which the substrate and the nozzle can be placed, to spray the aerosol; and a vacuum pump connected to a side of the deposition chamber to reduce pressure so as to form a vacuum therein. Through the components, uniform silicon carbide films can be formed in an upper part of the substrate.

Description

Silicon carbide heterojunction forming method and forming apparatus

The present invention relates to a method and apparatus for forming a silicon carbide heterojunction, and more particularly, by forming a heterojunction between a silicon carbide thin film and a substrate in which nano-sized silicon carbide powder is deposited using an aerosol deposition method to form a by-product in a low-temperature environment. The present invention relates to a method and apparatus for forming a thin film that is not produced.

Materials with a wide bandgap, such as silicon carbide, gallium nitride, zinc oxide, and gallium oxide, have durability at high temperatures. It is a material that has the potential to be applied in the same field of application.

Among them, silicon carbide is commercially available as a 150 mm wafer, has very high thermal conductivity, and is attracting attention because it can work in a power semiconductor having a high temperature and high power density and cool the generated heat.

In recent studies, a silicon carbide/silicon heterostructure has been studied to utilize the excellent thermal conductivity, wide bandgap, and chemical stability of silicon carbide. Due to the nanocrystalline silicon carbide, there is a problem in that a defect occurs in a high-temperature process and the performance is reduced.

Korean Patent Publication No. 10-1573010 Korean Patent Publication No. 10-2019-0087260

The present invention is a silicon carbide heterojunction forming method for forming a dense silicon carbide thin film without by-products at low temperature through an aerosol containing nano-sized silicon carbide powder and It is an object to provide a forming apparatus.

Silicon carbide heterojunction forming method and forming apparatus according to the present invention in order to achieve the object as described above, a powder drying step of drying silicon carbide powder having an average particle size of 50 or more and 200 nanometers or less; an aerosol preparation step of placing the silicon carbide powder dried in the powder drying step in an aerosol chamber; an aerosol forming step of supplying a supply gas from a supply gas storage tank to the aerosol chamber to form an aerosol; and a junction forming step of forming a heterojunction between the substrate and the silicon carbide thin film by spraying the aerosol onto the substrate.

In the powder drying step, the drying temperature may be 100 or more and 200 degrees or less.

In the aerosol forming step, the supply gas may be one of helium, nitrogen or air.

In the aerosol forming step, the flow rate of the supply gas may be 1 or more and 10 liters/minute or less.

In the bonding forming step, the vacuum degree of the deposition chamber may be 0.01 or more and 0.1 torr or less.

In the bonding forming step, the temperature in the deposition chamber may be set in a room temperature range of 5 degrees or more and 35 degrees or less.

In the junction forming step, one of n-type or p-type silicon, gallium arsenide compound, silicon carbide compound, and gallium nitride may be selected for the substrate.

In addition, the silicon carbide heterojunction forming method and apparatus according to the present invention in order to achieve the above object, silicon carbide powder having an average particle size of 50 or more and 200 nanometers or less is stored therein, and the silicon carbide powder is supplied an aerosol chamber in which an aerosol is formed by mixing with the gas; a supply gas pipe connected to the lower end of the aerosol chamber and having a flow path formed therein; a supply gas storage tank for supplying the supply gas through the supply gas pipe; a mass flow control device mounted on the supply gas pipe and controlling the flow rate of the supply gas; an aerosol tube connected to the upper end of the aerosol chamber and having a flow path therein; a nozzle connected to the aerosol tube and spraying the aerosol; a deposition chamber in which a space in which the substrate and the nozzle are provided is formed and the aerosol is sprayed; and a vacuum pump connected to the side surface of the deposition chamber to reduce the pressure so that the inside is in a vacuum state.

The substrate in the deposition chamber may be spaced apart from the nozzle by an interval of 1 or more and 10 mm or less.

The deposition chamber may further include an XY-axis stage to support the substrate and move in the X-axis or Y-axis to uniformly form a thin film.

As described above, according to the method and apparatus for forming a silicon carbide heterojunction according to the present invention, a silicon carbide thin film is formed by spraying an aerosol formed by mixing nano-sized silicon carbide powder and a supply gas to form a silicon carbide thin film. Since silicon carbide or silicon oxide is not formed, it is possible to utilize the wide band gap, high thermal conductivity, and high chemical stability of silicon carbide, and to manufacture highly integrated semiconductor devices and ultra-small sensors.

1 is a view schematically showing an apparatus for forming a silicon carbide heterojunction according to an embodiment of the present invention.
2 is a flowchart illustrating a method of forming a silicon carbide heterojunction according to another embodiment of the present invention.
3 is a view showing the shape of the silicon carbide powder used in the embodiment of the present invention.
Figure 4 is a view showing the state observed using the SEM of the silicon carbide thin film prepared according to the present invention.
5 is a view observed by cutting the silicon carbide thin film and the substrate prepared according to the present invention in the cross-sectional direction.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Since the present invention can have various changes and can have various embodiments, specific embodiments are illustrated in the drawings and will be described in detail in the detailed description. This is not intended to limit the present invention to specific embodiments, and should be construed to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

In describing the present invention, terms such as first, second, etc. may be used to describe various components, but the components may not be limited by the terms. The above terms are only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, a first component may be referred to as a second component, and similarly, a second component may also be referred to as a first component.

The term “and/or” may include a combination of a plurality of related listed items or any of a plurality of related listed items.

When a component is referred to as being “connected” or “connected” to another component, it may be directly connected or connected to the other component, but other components may exist in between. can be understood On the other hand, when it is mentioned that a certain element is "directly connected" or "directly connected" to another element, it may be understood that the other element does not exist in the middle.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. The singular expression may include the plural expression unless the context clearly dictates otherwise.

In the present application, terms such as "comprise" or "have" are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, and one or more other features It may be understood that the presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded in advance.

Unless defined otherwise, all terms used herein, including technical or scientific terms, may have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in a commonly used dictionary may be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in the present application, it is interpreted in an ideal or excessively formal meaning. it may not be

In addition, the following embodiments are provided to more completely explain to those with average knowledge in the art, and the shapes and sizes of elements in the drawings may be exaggerated for clearer description.

1, in the silicon carbide heterojunction forming apparatus according to an embodiment of the present invention, silicon carbide powder 21 having an average particle size of 50 or more and 200 nanometers or less is stored therein, and the silicon carbide powder 21 is supplied. An aerosol chamber 20 that is mixed with gas to form an aerosol, a supply gas pipe 11 connected to the lower end of the aerosol chamber 20 and having a flow path formed therein, and a supply gas supplying gas supply through the supply gas pipe 11 Tank 10, a mass flow control device 12 mounted on the supply gas pipe 11 and controlling the flow rate of the supply gas, an aerosol pipe 22 connected to the upper end of the aerosol chamber 20 and having a flow path formed therein, aerosol A nozzle 23 connected to the tube 22 and spraying the aerosol, a space in which the substrate 32 and the nozzle 23 are provided, the deposition chamber 30 in which the aerosol is sprayed, deposition It may include a vacuum pump 40 that is connected to the side of the chamber 30 to reduce the pressure so that the inside is in a vacuum state.

In the deposition chamber 30, the substrate 32 is spaced apart from the nozzle 23 by an interval of 1 or more and 10 mm or less to adjust the range in which the aerosol is sprayed to the substrate 32, thereby forming the silicon carbide thin film 31. can be adjusted.

In addition, a mass flow control device is additionally provided in the middle of the aerosol tube 22 to control the flow rate of the aerosol to control the hammering effect generated by spraying the aerosol to the substrate 32 to control the silicon carbide thin film 31 ) can be controlled.

In addition, an XY-axis stage 33 may be included to support the substrate 32 inside the deposition chamber 30 and move in the X-axis or Y-axis to uniformly form the silicon carbide thin film 31, XY The distance at which the substrate 32 is spaced apart from the nozzle 23 may be adjusted by additionally including a function of the axis stage 33 moving in the Z-axis.

Referring to Figure 2, the silicon carbide heterojunction forming method according to another embodiment of the present invention is a powder drying step (S10) of drying the silicon carbide powder 21 having an average particle size of 50 or more and 200 nanometers or less, in the powder drying step Aerosol preparation step (S20) of placing the dried silicon carbide powder 21 in the aerosol chamber 20, supply gas from the supply gas storage tank 10 to the aerosol chamber 20 to form an aerosol The forming step (S30), the aerosol is sprayed onto the substrate (32) to form a heterojunction between the substrate (32) and the silicon carbide thin film (31).

In FIG. 2, the silicon carbide heterojunction forming method is shown in four steps, but the present invention is not limited thereto, and may be divided or repeated according to detailed processes, all of which will fall within the scope of the present invention. . For convenience, a method of forming a silicon carbide heterojunction will be described in four steps.

In the powder drying step (S10), the silicon carbide powder 21 having an average particle size of 50 or more and 200 nanometers or less as shown in FIG. By heating with a furnace for 30 minutes or more, moisture adsorbed to the powder is removed to prevent the formation of bubbles when forming a thin film.

After the powder drying step (S10), in the aerosol preparation step (S20), 10 or more and 100 g or less of the dried silicon carbide powder 21 are selected and placed in the aerosol chamber 20.

After the aerosol preparation step (S20), in the aerosol forming step (S30), the supply gas of one of helium, nitrogen, or air stored in the supply gas storage tank 10 is supplied through the supply gas pipe 11 at 1 or more 10 liters / min. A uniform aerosol is formed by dispersing the dried silicon carbide powder 21 in the supply gas by supplying it to the aerosol chamber 20 at a flow rate.

In the aerosol formation step (S30), the mass flow control device 12 maintains a constant flow rate to form a uniform aerosol, and the aerosol through an algorithm through a separate software provided in the mass flow control device 12 The aerosol can be controlled by changing the flow rate according to the change in the mass of the chamber 20 .

After the aerosol forming step (S30), in the bonding forming step (S40), the formed aerosol is transferred through the aerosol tube 22 and the nozzle 23 connected to the aerosol chamber 20. The substrate 32 inside the deposition chamber 30. by spraying to form a silicon carbide thin film 31 having a heterojunction with the substrate 32 .

The substrate 32 used in the junction forming step S40 may use n-type or p-type silicon, a gallium arsenide compound, a silicon carbide compound, or gallium nitride.

In the bonding forming step ( S40 ), the deposition chamber 30 is evacuated through a vacuum pump to have a vacuum degree of 0.01 or more and 0.1 torr or less, and the temperature is set in a room temperature range of 5 degrees or more and 35 degrees or less.

Referring to FIGS. 1 and 2 , the XY-axis stage 33 rotates along the X and Y axes to have an inclination, so that a portion of the silicon carbide thin film 31 may be etched through the collision of the aerosol.

In addition, after placing the silicon carbide powder in the aerosol chamber, including a vacuum pump connected to the aerosol chamber and a heating device provided at the bottom of the aerosol chamber, using a vacuum pump inside the aerosol chamber in a vacuum 100 The powder drying step (S10) may be performed by heating to a drying temperature of about 200 degrees.

Referring to FIG. 4, the silicon carbide thin film 31 formed by using the above-described silicon carbide heterojunction forming method and forming apparatus is formed in a structure in which the silicon carbide powder 21 is connected, and the pore size is 1 micrometer or less. can

Referring to FIG. 5 , the thickness of the silicon carbide thin film 31 formed by using the above-described silicon carbide heterojunction forming method and forming apparatus has a size of about 150 micrometers and forms a heterojunction with the substrate 32 .

Although the present invention has been described in detail through specific examples, it is intended to describe the present invention in detail, and the present invention is not limited thereto. It is clear that the transformation or improvement is possible by the person.

All simple modifications and variations of the present invention fall within the scope of the present invention, and the specific scope of protection of the present invention will be made clear by the appended claims.

10: supply gas storage tank
11: supply gas pipe
12: mass flow control device
20: aerosol chamber
21: silicon carbide powder
22: aerosol tube
23 : Nozzle
30: deposition chamber
31: silicon carbide thin film
32: substrate
33: XY axis stage
40: vacuum pump

Claims (10)

Powder drying step of drying the silicon carbide powder having an average particle size of 50 or more and 200 nanometers or less;
an aerosol preparation step of placing the silicon carbide powder dried in the powder drying step in an aerosol chamber;
an aerosol forming step of supplying a supply gas from a supply gas storage tank to the aerosol chamber to form an aerosol; and
a junction forming step of forming a heterojunction between the substrate and the silicon carbide thin film by spraying the aerosol onto the substrate;
A method of forming a silicon carbide heterojunction comprising a. According to claim 1,
In the powder drying step,
A method of forming a silicon carbide heterojunction, characterized in that the drying temperature is 100 or more and 200 degrees or less. According to claim 1,
In the aerosol forming step,
The silicon carbide heterojunction forming method, characterized in that the supply gas is one of helium, nitrogen or air is selected. According to claim 1,
In the aerosol forming step,
Silicon carbide heterojunction forming method, characterized in that the flow rate of the supply gas is 1 to 10 liters / min or less. According to claim 1,
In the bonding forming step,
A method of forming a silicon carbide heterojunction, characterized in that the vacuum degree of the deposition chamber is 0.01 or more and 0.1 torr or less. According to claim 1,
In the bonding forming step,
A method for forming a silicon carbide heterojunction, characterized in that the temperature in the deposition chamber is set in a room temperature range of 5 degrees or more and 35 degrees or less. According to claim 1,
In the bonding forming step,
The method for forming a silicon carbide heterojunction, characterized in that the substrate is selected from among n-type or p-type silicon, gallium arsenide compound, silicon carbide compound, and gallium nitride. In the device for forming a heterojunction between a substrate and a silicon carbide thin film,
an aerosol chamber in which silicon carbide powder having an average particle size of 50 or more and 200 nanometers or less is stored therein, and the silicon carbide powder is mixed with a supply gas to form an aerosol;
a supply gas pipe connected to the lower end of the aerosol chamber and having a flow path formed therein;
a supply gas storage tank for supplying the supply gas through the supply gas pipe;
a mass flow control device mounted on the supply gas pipe and controlling the flow rate of the supply gas;
an aerosol tube connected to the upper end of the aerosol chamber and having a flow path therein;
a nozzle connected to the aerosol tube and spraying the aerosol;
a deposition chamber in which a space in which the substrate and the nozzle are provided is formed and the aerosol is sprayed; and
a vacuum pump connected to a side surface of the deposition chamber to depressurize the inside to be in a vacuum state;
Silicon carbide heterojunction forming apparatus comprising a. 9. The method of claim 8,
The silicon carbide heterojunction forming apparatus, characterized in that the substrate inside the deposition chamber is spaced apart from the nozzle by an interval of 1 or more and 10 mm or less. 9. The method of claim 8,
The deposition chamber supports the substrate and moves along the X-axis or the Y-axis to further include an XY-axis stage to uniformly form a thin film.

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