阅读说明：本技术 衬底处理设备 (Substrate processing apparatus ) 是由 李昌敏 于 2021-05-07 设计创作，主要内容包括：一种能够局部地控制等离子体强度并改善薄膜特性和厚度均匀性的衬底处理设备包括：供电单元、电连接到供电单元的处理单元和处理单元下方的衬底支撑单元,其中衬底支撑单元包括第一接地电极和第二接地电极。(A substrate processing apparatus capable of locally controlling plasma intensity and improving film characteristics and thickness uniformity, comprising: the substrate supporting unit comprises a power supply unit, a processing unit electrically connected to the power supply unit, and a substrate supporting unit below the processing unit, wherein the substrate supporting unit comprises a first grounding electrode and a second grounding electrode.)

1. A substrate processing apparatus, comprising:

a power supply unit;

a processing unit electrically connected to the power supply unit; and

a substrate supporting unit under the processing unit,

wherein the substrate supporting unit includes a first ground electrode and a second ground electrode.

2. The substrate processing apparatus of claim 1, wherein the processing unit is configured to function as an electrode for supplying power to the reaction space.

3. The substrate processing apparatus of claim 1, wherein the second ground electrode is spaced apart from the first ground electrode and disposed to surround the first ground electrode.

4. The substrate processing apparatus of claim 1, wherein the first ground electrode and the second ground electrode are electrically connected to ground, and

the substrate processing apparatus includes at least one of:

a first plasma intensity controller connected between the first ground electrode and the ground; and

a second plasma intensity controller connected between the second ground electrode and the ground.

5. The substrate processing apparatus of claim 4, wherein at least one of the first plasma intensity controller and the second plasma intensity controller comprises an L-C circuit comprising an inductor, a capacitor, and a variable capacitor.

6. The substrate processing apparatus of claim 1, wherein at least one of the first ground electrode and the second ground electrode comprises a plate-shaped ground electrode.

7. The substrate processing apparatus of claim 1, wherein at least one of the first ground electrode and the second ground electrode comprises a mesh ground electrode.

8. The substrate processing apparatus of claim 7, wherein the mesh ground electrode comprises:

a first ground line extending in a first direction; and

a second ground line extending in a second direction different from the first direction,

wherein the first ground line and the second ground line are electrically connected to each other.

9. The substrate processing apparatus of claim 8, wherein the first ground line and the second ground line contact each other at a portion where the first ground line and the second ground line intersect each other, and

the first ground line and the second ground line are electrically connected to each other at a contact therebetween.

10. The substrate processing apparatus of claim 8, wherein the first ground line and the second ground line are spaced apart from each other at a portion where the first ground line and the second ground line intersect each other, and

the first ground line and the second ground line are electrically connected to each other by a conductive member that connects an end of the first ground line to an end of the second ground line.

11. The substrate processing apparatus of claim 8, wherein, in a plurality of first portions where the first ground line and the second ground line intersect each other, a distance between an upper surface of the substrate support unit and the first ground line is larger than a distance between the upper surface of the substrate support unit and the second ground line, and

in a second portion other than the first portion, a distance between an upper surface of the substrate support unit and the first ground line is equal to a distance between the upper surface of the substrate support unit and the second ground line.

12. The substrate processing apparatus of claim 7, wherein the first ground electrode comprises a first mesh ground electrode, and

the second ground electrode comprises a second mesh ground electrode,

wherein the first mesh ground electrode and the second mesh ground electrode have different mesh densities.

13. The substrate processing apparatus of claim 1, wherein the first ground electrode is disposed at a different level than the second ground electrode.

14. The substrate processing apparatus of claim 13, wherein the first ground electrode and the second ground electrode partially overlap.

15. The substrate processing apparatus of claim 1, further comprising:

a first electrode rod contacting the first ground electrode; and

electrically connecting the first electrode rod to a grounded first connecting rod.

16. The substrate processing apparatus of claim 15, further comprising a first buffer rod between the first electrode rod and the first connecting rod.

17. The substrate processing apparatus of claim 16, wherein the first electrode rod comprises a first metal composition, and

the first connecting rod includes a second metal composition different from the first metal composition,

wherein the first buffer rod comprises an alloy composition of the first metal composition and the second metal composition.

18. The substrate processing apparatus of claim 1, wherein the substrate supporting unit further comprises:

a first heating unit under the first ground electrode; and

a second heating unit under the second ground electrode,

wherein the first heating unit and the second heating unit are independently controlled.

19. A substrate processing apparatus, comprising:

a power supply unit;

a showerhead electrode electrically connected to the power supply unit; and

a heating block arranged below the spray head electrode,

wherein the heating block includes a disk-shaped first ground electrode and an annular second ground electrode spaced apart from and surrounding the disk-shaped first ground electrode,

at least one of the disk-shaped first ground electrode and the ring-shaped second ground electrode is connected to an L-C circuit including an inductor, a capacitor, and a variable capacitor,

the L-C circuit is connected to ground, and

at least one of the density and intensity of the plasma in the reaction space is adjusted by parameter control of the L-C circuit.

20. A substrate processing apparatus, comprising:

a first ground electrode connected to ground; and

a second ground electrode spaced apart from the first ground electrode and connected to the ground.

Technical Field

One or more embodiments relate to a substrate processing apparatus, and more particularly, to a substrate processing apparatus configured to process a substrate by supplying plasma power through a processing unit disposed on the substrate.

Background

The substrate processing apparatus includes a heating block for heating a substrate to perform a process on the substrate. The substrate support unit including the heating block may also serve as an electrode during plasma processing. For example, in the in-situ plasma process, a heating block and a showerhead facing each other in a reaction space have functions of a lower electrode and an upper electrode, respectively.

As the size of the substrate to be processed increases, a local variation phenomenon of plasma density occurs, and as a result, the thin film property and thickness uniformity of the center and edge portions of the substrate may be deteriorated. The problem of deterioration of uniformity of plasma is also mentioned in japanese patent laid-open No. 2004-363552. In more detail, according to paragraph [0004], one or more embodiments include a substrate processing apparatus capable of reducing plasma non-uniformity across a substrate.

Disclosure of Invention

Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the presented embodiments of the disclosure.

According to one or more embodiments, a substrate processing apparatus includes a power supply unit, a processing unit electrically connected to the power supply unit, and a substrate supporting unit under the processing unit, wherein the substrate supporting unit includes a first ground electrode and a second ground electrode.

According to an embodiment of the substrate processing apparatus, the processing unit may be configured as an electrode for supplying power to the reaction space.

According to a further embodiment of the substrate processing apparatus, the second ground electrode may be spaced apart from and arranged to surround the first ground electrode.

According to a further embodiment of the substrate processing apparatus, the first ground electrode and the second ground electrode may be electrically connected to ground, and the substrate processing apparatus may comprise at least one of: a first plasma intensity controller connected between the first ground electrode and ground, and a second plasma intensity controller connected between the second ground electrode and ground.

According to another embodiment of a substrate processing apparatus, at least one of the first plasma intensity controller and the second plasma intensity controller may comprise an L-C circuit including an inductor, a capacitor, and a variable capacitor.

According to a further embodiment of the substrate processing apparatus, at least one of the first ground electrode and the second ground electrode may comprise a plate-shaped ground electrode.

According to a further embodiment of the substrate processing apparatus, at least one of the first ground electrode and the second ground electrode may comprise a mesh ground electrode.

According to another embodiment of the substrate processing apparatus, the mesh ground electrode includes a first ground line extending in a first direction and a second ground line extending in a second direction different from the first direction, wherein the first ground line and the second ground line may be electrically connected to each other.

According to another embodiment of the substrate processing apparatus, the first ground line and the second ground line contact each other at a portion where the first ground line and the second ground line intersect each other, and the first ground line and the second ground line may be electrically connected to each other at a contact therebetween.

According to another embodiment of the substrate processing apparatus, the first ground line and the second ground line are spaced apart from each other at a portion where the first ground line and the second ground line intersect each other, and the first ground line and the second ground line may be electrically connected to each other by a conductive member connected between an end portion of the first ground line and an end portion of the second ground line.

According to another embodiment of the substrate processing apparatus, in a plurality of first portions where the first ground line and the second ground line intersect each other, a distance between the upper surface of the substrate supporting unit and the first ground line is greater than a distance between the upper surface of the substrate supporting unit and the second ground line, and in a second portion other than the first portions, the distance between the upper surface of the substrate supporting unit and the first ground line may be equal to the distance between the upper surface of the substrate supporting unit and the second ground line.

According to a further embodiment of the substrate processing apparatus, the first mesh ground electrode may comprise a first mesh ground electrode and the second mesh ground electrode may comprise a second mesh ground electrode, wherein the first mesh ground electrode and the second mesh ground electrode may have different mesh densities.

According to a further embodiment of the substrate processing apparatus, the first ground electrode may be arranged at a different level than the second ground electrode.

According to a further embodiment of the substrate processing apparatus, the first ground electrode and the second ground electrode may partially overlap.

According to another embodiment of the substrate processing apparatus, the substrate processing apparatus may further include a first electrode rod contacting the first ground electrode, and a first connection rod electrically connecting the first electrode rod to ground.

According to another embodiment of the substrate processing apparatus, the substrate processing apparatus may further include a first buffer rod between the first electrode rod and the first connection rod.

According to another embodiment of the substrate processing apparatus, the first electrode rod may include a first metal composition, and the first connecting rod may include a second metal composition different from the first metal composition, wherein the first buffer rod may include an alloy composition of the first metal composition and the second metal composition.

According to another embodiment of the substrate processing apparatus, the substrate supporting unit may include a first heating unit under the first ground electrode and a second heating unit under the second ground electrode, wherein the first heating unit and the second heating unit may be independently controlled.

According to one or more embodiments, a substrate processing apparatus includes a power supply unit, a showerhead electrode electrically connected to the power supply unit, and a heating block under the showerhead electrode, wherein the heating block includes a disk-shaped first ground electrode and an annular second ground electrode spaced apart from and surrounding the disk-shaped first ground electrode, at least one of the disk-shaped first ground electrode and the annular second ground electrode is connected to an L-C circuit including an inductor, a capacitor, and a variable capacitor, the L-C circuit is connected to ground, and at least one of density and intensity of plasma in a reaction space can be adjusted by parameter control of the L-C circuit.

According to one or more embodiments, a substrate processing apparatus includes a first ground electrode connected to ground, and a second ground electrode spaced apart from the first ground electrode and connected to ground.

Drawings

The above and other aspects, features and advantages of certain embodiments of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a view of a substrate processing apparatus according to an embodiment of the inventive concept;

fig. 2 and 3 are views of a mesh ground electrode according to the inventive concept;

FIGS. 4A and 4B are views of a substrate processing apparatus according to an embodiment of the inventive concept;

FIG. 5 is a view of an RF ground electrode in a heating block according to an embodiment of the inventive concept;

fig. 6 is a view illustrating a case where a distance between an RF ground electrode and a surface of a heating block is different for each position according to an embodiment of the inventive concept;

fig. 7 is a view illustrating an arrangement of RF ground lines according to an embodiment of the inventive concept;

FIG. 8 is a view showing a substrate processing apparatus according to the inventive concept;

FIG. 9 is a cross-sectional view of a heating block according to an embodiment of the inventive concept;

FIG. 10 is a view of a connection structure between an RF ground electrode and an RF electrode rod according to an embodiment of the inventive concept;

fig. 11 is a view of an arrangement of an RF ground electrode and a heating element such as a heating wire according to an embodiment of the inventive concept; and

fig. 12 is a view of plasma intensity distribution in a reactor equipped with a heating block according to an embodiment of the inventive concept.

Detailed Description

Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. In this regard, the present embodiments may have different forms and should not be construed as limited to the description set forth herein. Accordingly, the embodiments are described below in order to explain aspects of the present specification by referring to the figures only. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. Prior to the list of elements, expressions such as "at least one of …" modify the entire list of elements without modifying the individual elements in the list.

In this regard, the present embodiments may have different forms and should not be construed as limited to the description set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting of the disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used herein, specify the presence of stated features, integers, steps, operations, elements, components, and/or groups, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are not intended to denote any order, quantity, or importance, but rather are used to distinguish one element, region, layer, and/or section from another element, region, layer, and/or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the embodiments.

Embodiments of the present disclosure will be described hereinafter with reference to the accompanying drawings, in which embodiments of the disclosure are schematically shown. In the drawings, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Accordingly, embodiments of the present disclosure should not be construed as limited to the particular shapes of regions illustrated herein but may include deviations in shapes that result, for example, from manufacturing processes.

Fig. 1 is a view of a substrate processing apparatus according to an embodiment of the inventive concept.

Referring to fig. 1, the substrate processing apparatus may include a power supply unit PWR, a processing unit 110, and a substrate support unit 150.

The power supply unit PWR may generate power. The power may for example be electrical energy for generating a plasma. In another example, the power may be the plasma itself. The generated power may be transmitted to the processing unit 110. For example, the power supply unit PWR may be electrically connected to the processing unit 110 through an RF rod, and thus, power (e.g., RF power) generated by the power supply unit may be transmitted to the processing unit 110 through the RF rod.

The processing unit 110 may be located on a substrate supporting unit 150 configured to support a substrate. The reaction space 51 may be defined between the substrate support unit 150 and the process unit 110. The processing unit 110 may be a conductor and may be an electrode for generating plasma. That is, the processing unit 110 may serve as one electrode for generating plasma. The plasma may be generated in the reaction space 51 through the processing unit 110 electrically connected to the power supply unit PWR. In other words, the processing unit 110 may serve as a plasma electrode that supplies power to the reaction space 51.

The processing unit 110 may include a member that performs an appropriate function according to the function of the substrate processing apparatus. For example, the processing unit 110 can include a reactant supply (e.g., a showerhead assembly) when the substrate processing apparatus performs a deposition function. In another embodiment, the processing unit 110 may include a polishing pad when the reactor performs a polishing function. In some embodiments, the processing unit 110 can be referred to as a showerhead electrode when the processing unit 110 itself acts as a showerhead assembly while acting as an electrode.

The substrate supporting unit 150 may be configured to provide a region on which a substrate S (e.g., a semiconductor substrate or a display substrate) to be processed is seated. The substrate supporting unit 150 may be under the processing unit 110. The substrate supporting unit 150 may be supported by a support (not shown) capable of up and down rotational movement. In addition, the substrate supporting unit 150 may include a conductor, and the substrate supporting unit 150 may serve as an electrode (i.e., an opposite electrode of the gas supply electrode) that generates plasma using the conductor.

The substrate supporting unit 150 may include a first ground electrode GE1, a second ground electrode GE2, a first heating unit HU1, a second heating unit HU2, a first plasma intensity controller PC1, and a second plasma intensity controller PC 2. Such a structure including a ground electrode and a heating unit may be referred to herein as a heating block.

The first ground electrode GE1 and the second ground electrode GE2 may be spaced apart from each other. For example, the first ground electrode GE1 may be at the center of the substrate support unit 150, and the second ground electrode GE2 may be disposed to surround the first ground electrode GE 1. In an example, the first ground electrode GE1 may be in the form of a disk (e.g., a circular or square disk) and the second ground electrode GE2 may be in the form of a ring (e.g., a circular or square ring) surrounding the first ground electrode GE 1.

In some embodiments, the substrate supporting unit 150 may include three or more ground electrodes. For example, the three or more ground electrodes may include a center electrode disposed at the center, a first ring electrode surrounding the center electrode, and a second ring electrode surrounding the first ring electrode.

The first ground electrode GE1 and the second ground electrode GE2 may be selectively electrically connected to the ground GND, respectively. That is, the ground electrodes GE1 and GE2 in the substrate supporting unit 150 are not connected to the power supply unit PWR that supplies power, but are connected to the ground GND. Accordingly, a path through which power (e.g., RF power) supplied through the processing unit 110 moves to the ground GND may include a first path passing through the first ground electrode GE1 and a second path passing through the second ground electrode GE 2.

At least one of the first channel and the second channel may comprise a rod. For example, when the first channel comprises a rod, the first channel may comprise a single rod. In some embodiments, the first channel may include a plurality of rods. The second channel may comprise a rod, and in some examples, the first channel and the second channel may comprise separate rods.

When the first channel comprises a plurality of rods, the first channel may comprise a first electrode rod and a first connecting rod. The first electrode rod may contact the first ground electrode GE 1. The first connecting rod may electrically connect the first electrode rod to the ground GND. In some embodiments, a first buffer rod may be arranged between the first electrode rod and the first connecting rod.

In further embodiments, the first buffer rods may include an alloy composition of the first electrode rods and the first connecting rods. For example, when the first electrode rod includes molybdenum (Mo) and the first connecting rod includes nickel (Ni), the first buffer rod may include a Mo — Ni alloy.

The first plasma intensity controller PC1 may be connected between the first ground electrode GE1 and ground GND. Therefore, the power moved to the ground GND through the first channel may be controlled by the first plasma intensity controller PC 1. The second plasma intensity controller PC2 may be connected between the second ground electrode GE2 and ground GND. Therefore, the power moved to the ground GND through the second channel can be controlled by the second plasma intensity controller PC 2.

In some embodiments, the plasma intensity controller (e.g., the first plasma intensity controller PC1 and/or the second plasma intensity controller PC2) may include an L-C circuit including an inductor, a capacitor, and a variable capacitor. In some embodiments, the L-C circuitry may be contained only in the first plasma intensity controller PC1, while in other embodiments, the L-C circuitry may be contained only in the second plasma intensity controller PC 2. In another embodiment, the L-C circuit may be included in both the first plasma intensity controller PC1 and the second plasma intensity controller PC 2.

The first plasma intensity controller PC1 and the second plasma intensity controller PC2 may have different parameters. By controlling these parameters, the density and intensity of the plasma can be adjusted in the reaction space. In further examples, the plasma intensity controller may include a circuit configuration other than an L-C circuit (e.g., a band pass filter).

In some embodiments, the first ground electrode GE1 and the second ground electrode GE2 (or any one of them) may include plate-shaped ground electrodes. For example, the first ground electrode GE1 may include a circular plate or a square plate, and the second ground electrode GE2 may be a circular disk or a square disk surrounding the first ground electrode GE 1.

In some other embodiments, the first ground electrode GE1 and the second ground electrode GE2 (or any one of them) may include mesh ground electrodes. For example, the first ground electrode GE1 may be a disk-shaped mesh ground electrode in which a plurality of conductor wires cross, and the second ground electrode GE2 may be a ring-shaped mesh ground electrode i in which a plurality of conductor wires cross. In examples where the first ground electrode GE1 includes a first mesh ground electrode and the second ground electrode GE2 includes a second mesh ground electrode, the first mesh ground electrode and the second mesh ground electrode may have different mesh densities. Due to this difference in the grid density, the plasma density or intensity on the substrate can be adjusted.

In some embodiments with respect to mesh ground electrodes, referring to fig. 2 and 3, the mesh ground electrode may include a first ground line C1 extending in a first direction and a second ground line C2 extending in a second direction different from the first direction. Further, the first ground line C1 and the second ground line C2 may be electrically connected to each other. The first and second ground lines C1 and C2 may be arranged to be inserted into the substrate-supporting unit 150.

In some examples, referring to fig. 2, first and second ground lines C1 and C2 may contact at a portion P where first and second ground lines C1 and C2 intersect. The mesh ground electrode in which the first ground line C1 and the second ground line C2 are electrically connected may be realized by a contact at an intersection.

In another example, referring to fig. 3, first and second ground lines C1 and C2 may be spaced apart from each other at a portion P' where first and second ground lines C1 and C2 intersect. In this case, the first and second ground lines C1 and C2 may be in contact at the edge. For example, the conductive member C3 may connect an end of the first ground line C1 to an end of the second ground line C2. The mesh ground electrode in which the first ground line C1 and the second ground line C2 are electrically connected may be realized by a contact at an edge.

As shown in fig. 2 and 3, in a plurality of first portions where the first and second ground lines C1 and C2 intersect, a distance F1 between the upper surface of the substrate support unit 150 and the first ground line C1 may be greater than a distance F2 between the upper surface of the substrate support unit 150 and the second ground line C2. On the other hand, in a second portion other than the first portion, in which the first ground line C1 and the second ground line C2 do not intersect, the distance F2' between the upper surface of the substrate support unit 150 and the first ground line C1 may be the same as the distance F2 "(fig. 2) between the upper surface of the substrate support unit 150 and the second ground line C2. Therefore, in the center region of the mesh ground electrode, the distance between the upper surface of the substrate support unit 150 and the ground wires (i.e., the first ground wire C1 and the second ground wire C2) can be kept constant.

Although fig. 1 shows that the first ground electrode GE1 and the second ground electrode GE2 are disposed at the same height, the first ground electrode GE1 may be disposed at a different level from the second ground electrode GE 2. In other words, the distance between the upper surface of the substrate supporting unit 150 and the first ground electrode GE1 may be different from the distance between the upper surface of the substrate supporting unit 150 and the second ground electrode GE 2.

Due to the level difference between the first ground electrode GE1 and the second ground electrode GE2, the density or intensity of plasma can be adjusted for each position of the reaction space. For example, when the first ground electrode GE1 at the center of the reaction space is disposed at a higher level than the second ground electrode GE2 at the edge of the reaction space, plasma having a greater intensity may be applied to the center or the edge of the reaction space.

When the first ground electrode GE1 is disposed at a different height from the second ground electrode GE2, the distance between the first ground electrode GE1 and the second ground electrode GE2 in the horizontal direction (i.e., the extending direction of the first ground electrode GE1 and the second ground electrode GE 2) may be zero. In addition, in some other embodiments, the first ground electrode GE1 and the second ground electrode GE2 may partially overlap in a horizontal direction.

Referring again to fig. 1, the first heating unit HU1 may be under the first ground electrode GE1, and the second heating unit HU2 may be under the second ground electrode GE 2. The first heating unit HU1 may have a shape corresponding to the first ground electrode GE1, and the second heating unit HU2 may have a shape corresponding to the second ground electrode GE 2. For example, when the first ground electrode GE1 is a disk-shaped electrode, the first heating unit HU1 may have a disk shape. Further, when the second ground electrode GE2 is an annular electrode, the second heating unit HU2 may also have an annular shape.

The first heating unit HU1 and the second heating unit HU2 may be independently controlled. For example, the controller CON may be electrically connected to the first and second heating units HU1 and HU2, and may generate a first signal for controlling the first heating unit HU1 and a second heating signal for controlling the heating unit HU2 from the controller CON. The first signal and the second signal can be transmitted to the first heating unit HU1 and the second heating unit HU2, respectively, via different channels. In the above-described embodiment, a plurality of heating units are disclosed, but the present disclosure is not limited thereto, and may be configured as a single unit. In this case, the controller CON may generate and transmit a single signal to the heating unit.

Fig. 4A and 4B are substrate processing apparatuses according to embodiments of the inventive concept, and illustrate, and for ease of understanding, a state in which heating elements such as heating wires are omitted. The substrate processing apparatus according to these embodiments may be a modification of the substrate processing apparatus according to the above-described embodiments. Hereinafter, a repetitive description of the embodiments will not be given here.

Referring to fig. 4A and 4B, the heating block 1 includes an RF ground electrode therein, wherein a plurality of RF ground electrodes are arranged independently of each other. The RF ground electrode includes a first RF ground electrode 2 and a second RF ground electrode 3, and the second RF ground electrode 3 is configured to surround the first RF ground electrode 2. In fig. 4A, a first RF ground bar 4 is connected to a first RF ground electrode 2, a second RF ground bar 5 is connected to a second RF ground electrode 3, and the first RF ground electrode 2 and the second RF ground electrode 3 are connected to ground through the first RF ground bar 4 and the second RF ground bar 5, respectively.

In the case of a heating block comprising plate-like electrodes therein, the characteristics of the electrodes are process variables that affect the process on the substrate. For example, differences in the coefficient of thermal expansion between the electrode and the heater block during high temperature processes, the particular shape of the plate-like electrode, etc., can affect process repeatability and uniformity of processes performed on the substrate, such as uniformity of films deposited during thin film processes, uniformity of plasma on the heater block, etc. Typically, the plate electrodes in the heating block comprise a single layer of plate electrodes to achieve plasma uniformity across the substrate. However, in practice, there is a problem in that uniformity of the substrate process is deteriorated due to heat loss, non-uniformity of gas flow supplied on the substrate, and the like. For example, local deviation of plasma density may occur due to non-uniform distribution of gas on the substrate, and uniformity of film characteristics and thickness at the center and edge of the substrate may be deteriorated. However, in the substrate processing apparatus according to the inventive concept, the first RF ground electrode 2 and the second RF ground electrode 3 are disposed to be spaced apart from each other, so that the non-uniformity of plasma at the center and edge of the substrate can be independently controlled, and thus the uniformity of the film characteristics and the thickness of the film on the substrate can be improved.

The first RF ground electrode 2 and the second RF ground electrode 3 may be formed in a mesh shape and spaced apart from each other by a distance d 1. Typically, the RF ground electrode embedded in the heating block is made by printing to have a full plate-like shape. However, during high temperatures, stress differences may occur due to differences in the coefficient of thermal expansion between the heater block and the embedded RF ground electrode, resulting in damage to the heater block. For example, since the thermal expansion coefficient of the heating block including the AlN material is 4.5 × 10^-6/° c, and the coefficient of thermal expansion of an RF ground electrode comprising a Mo material is 4.8x10^-6The stress difference at high temperature may cause the heating block to separate or break at/° c.

On the other hand, in the present disclosure, since the RF ground electrode is mesh-shaped, a constituent material (e.g., AlN) of the heating block is filled between the electrode wires to minimize damage to the heating block due to a stress difference. More specifically, as shown in fig. 5A, which shows an integrated RF ground electrode 2 in a prior art heating block, a heating block 1 is divided into an upper portion a and a lower portion B by the RF ground electrode 2. During high temperatures, the upper and lower portions of the heating block may separate or crack due to stress differences (see arrows) between the heating block 1 and the RF ground electrode 2. However, in the structure of fig. 5B according to the present disclosure, the upper portion a and the lower portion B of the heating block are connected to each other through the region C between the portions of the mesh of the RF ground electrode, and therefore, the technical feature of the structure is that the separation or breakage of the heating block 1 during high temperature can be suppressed.

Referring again to fig. 4A and 4B, the first RF ground rod 4 is connected to the first L-CThe resonant circuit 7 and the second RF ground rod 5 is connected to a second L-C resonant circuit 8. The L-C circuit comprises an inductor L, a capacitor C and a variable capacitor C_varAnd controls the plasma intensity on the RF ground electrode. In addition to LC circuits, circuits for controlling the plasma intensity on the RF ground electrode are also suitable. As an example of the technical features of this configuration, the thickness and characteristics of the thin film on the substrate can be locally controlled. In the case of the heating block, the temperature of the peripheral portion is lower than that of the central portion, and the characteristics or thickness of the thin film of the peripheral portion may be different from that of the central portion. Alternatively, when exhaust ports of a substrate processing apparatus equipped with a plurality of reactors are asymmetrically arranged, the characteristics or thickness of a thin film at a specific position on a substrate may be different from those of a thin film at a central portion. Accordingly, by the configuration of the heating block according to the present disclosure, the thin film characteristics and thickness uniformity may be controlled and improved.

Although fig. 4A shows the first L-C resonant circuit 7 and the second L-C resonant circuit 8 being grounded (i.e., connected to ground), in other embodiments, the first L-C resonant circuit 7 and the second L-C resonant circuit 8 may be connected to a controller (not shown). The controller may receive plasma intensity information measured by a plasma probe capable of monitoring plasma in the reactor in real time, and may control the first LC resonance circuit 7 or the second LC resonance circuit 8 based on the plasma intensity information.

As shown in fig. 4B, first RF ground electrode 2 and second RF ground electrode 3 are spaced apart from each other by a distance d1, thereby making it easy to control plasma at the center and edge of the substrate, respectively. Distance d1 has the technical feature of preventing first RF ground electrode 2 and second RF ground electrode 3 from contacting each other due to thermal expansion. Preferably, the distance d1 is configured to be at least 5mm or greater.

Also in fig. 4A, the diameter of first RF ground electrode 2 is smaller than the diameter of substrate 6. Therefore, plasma control of the inner surface portion other than the edge portion of the substrate 6 is facilitated. The inner diameter of second RF ground electrode 3 is at least larger than the inner diameter of substrate 6. Therefore, plasma control of the edge portion of the substrate 6 is facilitated.

In fig. 4A, the distance d2 between RF ground electrodes 2 and 3 and the upper surface of heating block 1 is preferably maintained at 1 mm. When the distance d2 is 1mm or less, the heating block 1 may be damaged due to deformation caused by thermal expansion of the RF ground electrode at high temperature, and when the distance d2 is 1mm or more, the plasma intensity on the substrate may be reduced and more RF power needs to be supplied to maintain process uniformity.

The distance d2 between the RF ground electrodes 2 and 3 and the upper surface of the heating block 1 affects the plasma distribution and plasma intensity on the substrate. The RF ground electrode according to the present disclosure is configured in a mesh shape, and since a portion where the electrode wire intersects in the horizontal and vertical directions (XY axes) is protruded, a distance d2 between the intersecting portion and the surface of the heating block 1 may be different from a distance d2 between the non-intersecting portion and the surface of the heating block 1.

FIG. 6 is a view showing a case where the distance between the RF ground electrode and the surface of the heating block is different for each position; in fig. 6(a) and 6(b), the distance from the position where RF ground electrode line W2 arranged in the X-axis direction and RF ground electrode line W3 arranged in the Y-axis direction intersect to the upper surface of heating block 1 is different from the distance from the position where RF ground electrode line W2 and RF ground electrode line W3 do not intersect to the upper surface of heating block 1 (d3 ≠ d 4). Therefore, the RF ground line must be arranged so that the distance to the upper surface of the heating block is constant regardless of whether the RF ground line intersects.

Fig. 7 is a view of an example of an arrangement of RF ground lines according to the present disclosure. In fig. 7, the distance from the portion where RF ground electrode lines W2 and W3 arranged in the X and Y axis directions intersect to the upper surface of heating block 1 is the same as the distance from the portion where RF ground electrode lines W2 and W3 do not intersect to the upper surface of heating block 1 (d3 — d 4). Thus, a technical feature of the embodiment of fig. 7 is that it is easier to precisely control the plasma on the substrate.

Fig. 8 is a view of other embodiments of a substrate processing apparatus according to the present disclosure. Referring to fig. 8, the distance d5 between the first RF ground electrode 2 and the surface of the heating block is different from the distance d6 between the second RF ground electrode 3 and the surface of the heating block (d5 ≠ d 6).

According to the embodiment of fig. 8, unlike those shown in fig. 4A and 4B, plasma intensity can be controlled separately at the center and the periphery of the substrate by using the distance difference between the corresponding RF ground electrode and the upper surface of the heating block even if a single LC resonance circuit is applied. In addition, as shown in fig. 4A and 4B are different, since the two RF ground electrodes are not on the same plane, the distance (g ═ 0) can be set without considering thermal expansion.

Figure 9 is a cross-sectional view of a heating block according to the present disclosure, viewed from a different direction.

Referring to fig. 9, RF ground electrodes 2 and 3 are located between heating element 9 and the upper surface of heating block 1. The first RF ground electrode 2 and the second RF ground electrode 3 are connected to the first RF ground bar 4 and the second RF ground bar 5, respectively, and the power bar 10 of the heating block 1 supplies power to the heating element 9.

Fig. 10 is a view of a connection structure between an RF ground electrode and an RF electrode rod.

Referring to fig. 10, RF ground electrode 11 is mesh-shaped. In fig. 10, the RF ground electrode 11 and the RF ground electrode rod 12 comprise the same material, such as Mo, and the RF ground rod 14 comprises a conductive material, such as Ni. The buffer electrode rods 13 connect the RF ground electrode rods 12 to the RF ground rods 14, and include constituent materials of the RF ground electrode rods 12 and the RF ground rods 14. For example, when the RF ground electrode rod 12 comprises Mo and the RF ground rod 14 comprises Ni, the buffer electrode rod 13 comprises a Mo-Ni alloy. As a result, the embodiment of fig. 10 is technically characterized in that the RF ground electrode rod 12 and the RF ground rod 14, which include metal materials having different thermal expansion coefficients, can be prevented from deviating or separating from each other at high temperatures.

Fig. 11 shows the upper surface of the heating block 1 of fig. 9 and shows the arrangement of the RF ground electrodes 2 and 3 and the heating element 9. As described above, each of the RF ground electrodes 2 and 3 is mesh-shaped, and the heating elements 9 are arranged to constitute a two-zone heating block, which is independently provided at the center and the periphery of the heating block 1, and forms a concentric shape based on the center of the heating block 1. The second boundary line B2 dividing the two-zone heating block corresponds to the first boundary line B1 dividing the first RF ground electrode 2 and the second RF ground electrode 3. The first boundary line B1 and the second boundary line B2 may be symmetrical to each other. For example, when the first boundary line B1 and the second boundary line B2 are circles, they may have the same diameter.

Fig. 12 shows plasma intensity distribution in a reactor equipped with a heating block according to the present disclosure. Fig. 12 shows that the plasma intensity is individually controlled by RF ground electrodes arranged at the center and the periphery, and the plasma intensity may be the same or different according to the purpose at the substrate.

Thus, according to an embodiment of the present invention, by disposing mesh-type RF ground electrodes at the center and the periphery of the heating block, respectively, and connecting an LC resonance circuit to each RF ground electrode, the plasma intensity on the substrate can be locally controlled during plasma processing, and the film characteristics or thickness uniformity can be improved.

It should be understood that the shape of each part of the drawings is exemplary for clarity of understanding of the present disclosure. It should be noted that these portions may be modified into various shapes other than the illustrated shapes.

It is to be understood that the embodiments described herein are to be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects in each embodiment should generally be considered as available for other similar features or aspects in other embodiments. Although one or more embodiments have been described with reference to the accompanying drawings, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by the following claims.