KR20220058777A - Substrate treating appartus and substrate treating method - Google Patents

Abstract

Disclosed is a substrate processing apparatus to uniformly control the plasma density inside a processing chamber. According to the present invention, the substrate processing apparatus comprises: a processing chamber including a housing having a processing space with the open upper part and a window covering the open upper part; a support unit disposed in the processing chamber to support a substrate; a gas supply unit supplying a process gas into the processing chamber; a plasma generation unit generating plasma from the process gas; and a microwave unit applying microwaves to the processing chamber. The plasma generation unit includes an upper electrode disposed on the upper part of the substrate, a lower electrode disposed on the lower part of the substrate to face the upper electrode in the vertical direction, and a plurality of RF power sources applying RF power to the lower electrode.

Description

Substrate processing apparatus and substrate processing method {SUBSTRATE TREATING APPARTUS AND SUBSTRATE TREATING METHOD}

The present invention relates to a substrate processing apparatus and a substrate processing method. More particularly, the invention relates to a heat treatment apparatus using microwaves.

In a conventional substrate processing apparatus, a substrate is heated using a ceramic heater for annealing the substrate. In the case of a method of heating a substrate using a conventional heater, there is a disadvantage that it takes a long time to increase and decrease the temperature. In addition, there is a problem in that the temperature of the entire substrate rises. In addition, there was a limit to high temperature heating over 150 degrees.

In order to solve this problem, a heating method using a laser or a method using a flash lamp has been proposed, but in these methods, it is difficult to raise the temperature of the entire substrate.

Therefore, a new heating method capable of annealing only the surface temperature of the substrate at a high speed is required.

An object of the present invention is to provide a substrate processing apparatus capable of heating a substrate without using a heater.

The problems to be solved by the present invention are not limited to the problems mentioned above. Other technical problems not mentioned will be clearly understood by those of ordinary skill in the art to which the present invention belongs from the following description.

A process chamber comprising: a housing having an open upper processing space and a window covering the open upper portion according to an exemplary embodiment of the present invention; a support unit disposed in the process chamber to support a substrate; a gas supply unit supplying a process gas into the process chamber; a plasma generating unit generating plasma from the process gas; and a microwave unit for applying a microwave to the process chamber, wherein the plasma generating unit includes: an upper electrode disposed on the substrate; a lower electrode disposed under the substrate to face the upper electrode in a vertical direction; and a plurality of RF power supplies for applying high-frequency power to the lower electrode.

According to an example, the substrate processing apparatus further comprising a DC power source connected to the lower electrode.

According to an example, the density of plasma in the chamber may be adjusted by combining the plasma generating unit, the microwave unit, and the DC power source.

According to one example, the microwave unit may be provided through the window.

According to one example, the window may be provided with a groove formed in the center in which the microwave unit can be mounted.

According to one example, the microwave unit may include a microwave plasma torch.

According to an example, by adjusting the pressure of the microwave plasma torch, the plasma density in the process chamber or the heat treatment of the substrate may be controlled.

According to an example, the substrate processing apparatus may be used in a thermal atomic layer etching (ALE) process using heat.

A method of performing substrate processing using a substrate processing apparatus according to another exemplary embodiment of the present invention is disclosed.

The method may control the density of plasma in the chamber by combining the plasma generating unit, the microwave unit, and the DC power source.

According to one example, the heat treatment of the substrate may be performed using the microwave unit.

According to the present invention, the substrate can be heated without using a heater.

According to the present invention, it is possible to more uniformly control the plasma density inside the chamber.

The effects of the present invention are not limited to the effects described above. Effects not mentioned will be clearly understood by those of ordinary skill in the art to which the present invention pertains from this specification and the accompanying drawings.

1 is a diagram illustrating an example of a substrate processing apparatus according to an embodiment of the present invention.
2 is a view for explaining a plasma density control result according to various methods.
3 is a flowchart illustrating a substrate processing method according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those of ordinary skill in the art to which the present invention pertains can easily implement them. However, the present invention may be implemented in several different forms and is not limited to the embodiments described herein. In addition, in describing a preferred embodiment of the present invention in detail, if it is determined that a detailed description of a related well-known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. In addition, the same reference numerals are used throughout the drawings for parts having similar functions and functions.

"Including" a certain component means that other components may be further included, rather than excluding other components, unless otherwise stated. Specifically, 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 is present, and includes one or more other features or It should be understood that the existence or addition of numbers, steps, operations, components, parts, or combinations thereof does not preclude the possibility of addition.

The singular expression includes the plural expression unless the context clearly dictates otherwise. In addition, shapes and sizes of elements in the drawings may be exaggerated for clearer description.

Terms such as first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms. The above terms are used 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.

As used throughout this specification, '~ unit' is a unit that processes at least one function or operation, and may refer to, for example, a hardware component such as software, FPGA, or ASIC. However, '~part' is not meant to be limited to software or hardware. '~' may be configured to reside on an addressable storage medium or may be configured to refresh one or more processors.

As an example, '~ part' denotes components such as software components, object-oriented software components, class components and task components, processes, functions, properties, procedures, and sub It may include routines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. A function provided by a component and '~ unit' may be performed separately by a plurality of components and '~ unit', or may be integrated with other additional components.

Hereinafter, an embodiment of the present invention will be described in more detail with reference to the accompanying drawings. Embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be construed as being limited to the following embodiments. This embodiment is provided to more completely explain the present invention to those of ordinary skill in the art. Therefore, the shape of the element in the drawings is exaggerated to emphasize a clearer description.

1 is a diagram illustrating an example of a substrate processing apparatus 10 according to an embodiment of the present invention.

1 illustrates a substrate processing apparatus by a capacitively coupled plasma (CCP) processing method, but is not limited thereto, and the present invention is a substrate by an inductively coupled plasma (ICP) processing method. It can also be applied to processing devices.

Referring to FIG. 1 , the substrate processing apparatus 10 processes the substrate W using plasma. For example, the substrate processing apparatus 10 may perform an etching process on the substrate W. The substrate processing apparatus 10 may include a chamber 100 , a substrate support unit 200 , a plasma generation unit 300 , a gas supply unit, a baffle unit, and a microwave unit 500 .

The housing 110 has an open upper surface therein. The inner space of the housing 110 is provided as a processing space in which a substrate processing process is performed. The housing 110 is provided with a metal material. The housing 110 may be made of an aluminum material. The housing 110 may be grounded. An exhaust hole 102 is formed in the bottom surface of the housing 110 . The exhaust hole 102 is connected to the exhaust line 151 . Reaction by-products generated during the process and gas remaining in the inner space of the housing may be discharged to the outside through the exhaust line 151 . The inside of the housing 110 is decompressed to a predetermined pressure by the exhaust process.

The window unit 120 covers the open upper surface of the housing 110 . The window unit 120 is provided in a plate shape and seals the inner space of the housing 110 . The window unit 120 may include a dielectric substance window.

According to an example, the liner 130 may be provided inside the chamber 100 . The liner 130 may have a cylindrical shape with open top and bottom surfaces. The liner 130 may be provided to contact the inner surface of the chamber 100 . The liner 130 may protect the inner wall of the chamber 100 to prevent the inner wall of the chamber 100 from being damaged by arc discharge. In addition, it is possible to prevent impurities generated during the substrate processing process from being deposited on the inner wall of the chamber 100 .

The substrate support unit 200 may be positioned inside the chamber 100 . The substrate support unit 200 may support the substrate W. The substrate support unit 200 may include an electrostatic chuck 210 for adsorbing the substrate W using an electrostatic force. Alternatively, the substrate support unit 200 may support the substrate W in various ways such as mechanical clamping. Hereinafter, the substrate support unit 200 including the electrostatic chuck 210 will be described.

The substrate support unit 200 may include an electrostatic chuck 210 , a lower cover 250 , and a plate 270 . The substrate support unit 200 may be located inside the chamber 100 while being spaced apart from the bottom surface of the chamber 100 upwardly.

The electrostatic chuck 210 may include a dielectric plate 220 , a body 230 , and a focus ring 240 . The electrostatic chuck 210 may support the substrate W.

The dielectric plate 220 may be positioned on the top of the electrostatic chuck 210 . The dielectric plate 220 may be provided as a disk-shaped dielectric (dielectric substance). A substrate W may be placed on the upper surface of the dielectric plate 220 . The upper surface of the dielectric plate 220 may have a smaller radius than the substrate W. Therefore, the edge region of the substrate W may be located outside the dielectric plate 220 .

The first electrode 223 may be electrically connected to the first power source 223a. The first power source 223a may include a DC power source. A switch 223b may be installed between the first electrode 223 and the first power source 223a. The first electrode 223 may be electrically connected to the first power source 223a by ON/OFF of the switch 223b. When the switch 223b is turned on, a direct current may be applied to the first electrode 223 . An electrostatic force acts between the first electrode 223 and the substrate W by the current applied to the first electrode 223 , and the substrate W may be adsorbed to the dielectric plate 220 by the electrostatic force.

The body 230 may be positioned under the dielectric plate 220 . The bottom surface of the dielectric plate 220 and the top surface of the body 230 may be bonded by an adhesive 236 . The body 230 may be made of an aluminum material. The upper surface of the body 230 may be stepped so that the central region is higher than the edge region. The central region of the top surface of the body 230 has an area corresponding to the bottom surface of the dielectric plate 220 , and may be adhered to the bottom surface of the dielectric plate 220 . The body 230 may have a first circulation passage 231 , a second circulation passage 232 , and a second supply passage 233 formed therein.

The body 230 may include a metal plate. The body 230 may function as a lower electrode. In this case, the body 230 is connected to the lower power supply 233 . The lower power supply unit 233 applies power to the body 230 , that is, the lower electrode. The lower power supply unit 233 includes three lower power sources 236a , 237a , 238a , a matching unit 235 , and a pulse supply 280 . As an embodiment, two of the three lower power supplies are a first frequency power supply 236a and a second frequency power supply 237a having a frequency of 10 MHz or less, and the other lower power supply is a second power supply having a frequency of 10 MHz or higher. 3 may be a frequency power supply 238a. Switches 236b , 237b , and 238b are connected to each of the three lower power sources 236a , 237a , and 238a to be electrically connected to the lower electrode according to the ON/OFF of the switch 223b. The first frequency power source 236a and the second frequency power source 237a may control ion energy, and the third frequency power source 238a may control plasma density.

The pulse supply 280 may apply an ON/OFF pulse to the lower power sources 236a, 237a, and 238a. Pulsed high frequency power may be applied from the lower power sources 236a , 237a , and 238a to the body 230 , that is, the lower electrode according to the ON/OFF pulse applied by the pulse supply 280 .

The matching unit 225 is electrically connected to the first to third frequency power sources 236a, 237a, and 238a, and matches frequency powers of different magnitudes and applies them to the body 230 acting as a lower electrode.

The focus ring 240 may be disposed on an edge region of the electrostatic chuck 210 . The focus ring 240 has a ring shape and may be disposed along the circumference of the dielectric plate 220 . The upper surface of the focus ring 240 may be stepped such that the outer portion 240a is higher than the inner portion 240b. The inner portion 240b of the upper surface of the focus ring 240 may be positioned at the same height as the upper surface of the dielectric plate 220 . The upper inner portion 240b of the focus ring 240 may support an edge region of the substrate W positioned outside the dielectric plate 220 . The outer portion 240a of the focus ring 240 may be provided to surround an edge region of the substrate W. Referring to FIG. The focus ring 240 may control the electromagnetic field so that the density of plasma is uniformly distributed over the entire area of the substrate W. As a result, plasma is uniformly formed over the entire region of the substrate W, so that each region of the substrate W may be etched uniformly.

The lower cover 250 may be located at the lower end of the substrate support unit 200 . The lower cover 250 may be positioned to be spaced apart from the bottom surface of the chamber 100 upwardly. The lower cover 250 may have a space 255 having an open upper surface formed therein. The outer radius of the lower cover 250 may be provided to have the same length as the outer radius of the body 230 . In the inner space 255 of the lower cover 250 , a lift pin module (not shown) for moving the transferred substrate W from an external transfer member to the electrostatic chuck 210 may be positioned. The lift pin module (not shown) may be positioned to be spaced apart from the lower cover 250 by a predetermined distance. A bottom surface of the lower cover 250 may be made of a metal material. Air may be provided in the inner space 255 of the lower cover 250 . Since air has a lower dielectric constant than the insulator, it may serve to reduce the electromagnetic field inside the substrate support unit 200 .

The lower cover 250 may have a connection member 253 . The connecting member 253 may connect the outer surface of the lower cover 250 and the inner wall of the chamber 100 . A plurality of connection members 253 may be provided on the outer surface of the lower cover 250 at regular intervals. The connection member 253 may support the substrate support unit 200 in the chamber 100 . In addition, the connection member 253 may be connected to the inner wall of the chamber 100 so that the lower cover 250 is electrically grounded.

A plate 270 may be positioned between the electrostatic chuck 210 and the lower cover 250 . The plate 270 may cover the upper surface of the lower cover 250 . The plate 270 may be provided with a cross-sectional area corresponding to the body 230 . The plate 270 may include an insulator. According to an example, one or a plurality of plates 270 may be provided. The plate 270 may serve to increase the electrical distance between the body 230 and the lower cover 250 .

The plasma generating unit 300 may excite the process gas in the chamber 100 into a plasma state. The plasma generating unit 300 may use a capacitively coupled plasma type plasma source. When a CCP-type plasma source is used, the upper electrode 330 and the lower electrode, that is, the body 230 may be included in the chamber 100 . The upper electrode 330 and the lower electrode 230 may be vertically disposed parallel to each other with a processing space therebetween. The lower electrode 230 as well as the upper electrode 330 may receive an RF signal by the RF power source 310 to receive energy for generating plasma, and the number of RF signals applied to each electrode is as shown. are not limited to one. An electric field is formed in the space between the electrodes, and the process gas supplied to the space may be excited into a plasma state. A substrate processing process is performed using this plasma.

The gas supply unit supplies a process gas into the chamber 100 . The gas supply unit includes a gas supply nozzle, a gas supply line, and a gas storage unit. The gas supply line connects the gas supply nozzle and the gas storage unit. The gas supply line supplies the process gas stored in the gas storage unit to the gas supply nozzle. A valve is installed in the gas supply line. The valve opens and closes the gas supply line, and regulates the flow rate of the process gas supplied through the gas supply line.

The baffle unit may be positioned between the inner wall of the chamber 100 and the substrate support unit 200 . The baffle may be provided in the shape of an annular ring. A plurality of through-holes may be formed in the baffle. The process gas provided in the chamber 100 may pass through the through-holes of the baffle and be exhausted to the exhaust hole. The flow of the process gas may be controlled according to the shape of the baffle and the shape of the through-holes.

The microwave unit 500 is installed in the center of the window unit 120 . A spray hole may be formed on the bottom surface of the microwave unit 500 . The microwave unit 500 through the injection hole may apply a microwave into the chamber. The injection hole is located at the lower portion of the window unit 120 and supplies microwaves to the processing space inside the chamber 100 . Through this, heat treatment of the substrate may be performed.

In the window unit 120 of the present invention, a groove 121 in which the microwave unit 500 can be mounted may be formed in the center thereof. The groove 121 formed in the window unit 120 may be provided in a size corresponding to the waveguide 520 included in the microwave unit 500 . According to one example, the end of the waveguide 520 included in the microwave unit 500 may be mounted and coupled to the groove 121 of the window unit 120 .

Since the wavelength of the microwave is much longer than the thickness and spacing of the metal wiring layer of the semiconductor chip, the depth of penetration of the microwave into the metal material is less than several μm. According to one example, by heating the surface of the substrate or die by microwave heat treatment, there is an effect of rapidly increasing the surface temperature to a target temperature.

The microwave unit 500 may include a waveguide 520 for applying microwaves in the housing. The microwave unit 500 may apply a microwave of a frequency of 1 to 5 GHz. The waveguide 520 may apply microwaves generated from the magnetron 510 into the chamber. According to an example, the magnetron 510 may oscillate an electromagnetic wave in a band of 10 MHz to 10 GHz. Preferably, the magnetron 510 may oscillate a 2.45 GHz electromagnetic wave. Meanwhile, the plasma source may be provided as an inductively coupled plasma or a capacitively coupled plasma type. Plasma according to an embodiment of the present invention is atmospheric pressure plasma.

According to one embodiment of the present invention, since the surface of the substrate is selectively heated by microwaves, the temperature increase rate and cooling rate are fast, and the surface of the substrate can be heated to a target temperature within a short time, thereby shortening the process time. there is. The substrate processing apparatus 10 according to the present invention may be used in a thermal atomic layer etching (ALE) process using heat. According to one example, the substrate processing apparatus 1 according to the present invention may be used in a process including a heat treatment using microwave heat (wafer heat treatment). According to an example, the substrate processing apparatus 1 according to the present invention may be used in a thermal atomic layer deposition (t-ALD) process, a thermal atmic layer etching (t-ALE) process, and the like.

According to one example, the microwave unit 500 according to the present invention may include a microwave plasma torch (not shown). The microwave unit 500 according to the present invention performs plasma density control by adjusting the pressure discharged from the microwave plasma torch, or it can be used as a heating means of the substrate.

That is, according to the present invention, there is an effect that can quickly heat the surface of the substrate using a microwave plasma torch. In addition, there is an effect that the uniformity of the heat treatment can be controlled by adjusting the pressure of the plasma torch.

The present invention may further include a DC power supply 239 connected to the lower electrode.

According to an example of FIG. 1 , the DC power supply 239 is connected to the lower electrode through a separate connection line, but according to another embodiment, the DC power supply 239 and the plurality of RF power sources may be connected to the lower electrode through the same connection line.

According to the present invention, the density of plasma in the chamber can be adjusted by combining some of the plasma generating unit, the microwave unit 500 and the DC power source 239 .

According to one example, the density of plasma in the chamber may be adjusted by combining the plasma generating unit and the microwave unit 500 . According to another example, the density of plasma in the chamber may be adjusted by combining the plasma generating unit and the DC power supply 239 . According to this embodiment, the density of plasma in the chamber may be adjusted by combining the plasma generating unit and the DC power source 239 , and the heat treatment of the substrate may be performed using the microwave unit 500 .

That is, according to the present invention, the effect of increasing the plasma density control and the uniformity of the wafer heat treatment according to a combination of two or more of the microwave unit 500 and the RF power source 236a, 237a, 238a, and the DC power source 239 is there is. 2 is a view for explaining a plasma density control result according to various methods.

According to FIG. 2, the result of plasma control using only the microwave unit is shown on the far left, and the result of plasma control using only AC power is shown in the middle, and plasma control is performed by combining the two. The results obtained are shown on the far right. According to FIG. 2, when plasma control is performed using only the microwave unit, it can be confirmed that the plasma density is concentrated only in the early part with a short wavelength, and when plasma control is performed using only AC power, the plasma control is performed long and thin. can be checked

When the plasma control is performed by combining the two, it can be seen that the combined results of the case using the microwave unit and the case of using the AC power are displayed. That is, in this case, it can be confirmed that there is an effect that plasma control can be performed in a wider range compared to the conventional one.

3 is a flowchart illustrating a substrate processing method according to an embodiment of the present invention.

In the substrate processing method according to the present invention, the density of plasma in the chamber may be adjusted by combining the plasma generating unit, the microwave unit, and the DC power source 239 . In addition, heat treatment of the substrate may be performed using a microwave unit.

The present invention has the effect of performing more efficient plasma treatment by controlling the density of plasma through a combination of various plasma sources, and can perform faster heat treatment of the substrate through heat treatment using a microwave unit. It works.

It should be understood that the above embodiments are presented to help the understanding of the present invention, and do not limit the scope of the present invention, and various modified embodiments therefrom also fall within the scope of the present invention. The drawings provided in the present invention merely show an optimal embodiment of the present invention. The technical protection scope of the present invention should be defined by the technical idea of the claims, and the technical protection scope of the present invention is not limited to the literal description of the claims itself, but is substantially equivalent to the technical value. It should be understood that it extends to the invention of

10: substrate processing device
239: DC power
500: microwave unit

Claims (10)

a process chamber having a housing having an open upper processing space and a window covering the open upper portion;
a support unit disposed in the process chamber to support a substrate;
a gas supply unit supplying a process gas into the process chamber;
a plasma generating unit generating plasma from the process gas; and
Including; a microwave unit for applying a microwave to the process chamber;
The plasma generating unit,
an upper electrode disposed on the substrate;
a lower electrode disposed under the substrate to face the upper electrode in a vertical direction; and
and a plurality of RF power supplies for applying high-frequency power to the lower electrode.
According to claim 1,
The substrate processing apparatus further comprising a; DC power source connected to the lower electrode.
3. The method of claim 2,
A substrate processing apparatus for controlling a density of plasma in a chamber by combining the plasma generating unit, the microwave unit, and the DC power supply.
4. The method according to any one of claims 1 to 3,
The microwave unit is a substrate processing apparatus provided through the window.
5. The method of claim 4,
The window is a substrate processing apparatus provided with a groove formed in the center in which the microwave unit can be mounted.
6. The method of claim 5,
The microwave unit is a substrate processing apparatus comprising a microwave plasma torch.
7. The method of claim 6,
A substrate processing apparatus for controlling plasma density in the process chamber or heat treatment of the substrate by adjusting the pressure of the microwave plasma torch.
4. The method according to any one of claims 1 to 3,
The substrate processing apparatus is a substrate processing apparatus used in a thermal atomic layer etching (ALE) process using heat.
In the method of performing substrate processing using the substrate processing apparatus according to claim 2,
A substrate processing method for controlling a density of plasma in a chamber by combining the plasma generating unit, the microwave unit, and the DC power supply.
10. The method of claim 9,
A substrate processing method for performing heat treatment of the substrate using the microwave unit.

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