KR20230141119A - Moving Unit for Focus Ring and Apparatus for Treating Substrate - Google Patents

Abstract

The present invention provides a focus ring movement unit capable of moving a focus ring without opening a chamber. One embodiment provides the focus ring movement unit which comprises: a pin extending in a vertical direction to be inserted into a groove formed on a lower surface of a focus ring surrounding an electrostatic chuck; and a first moving unit connected to a pin and moving the pin in a horizontal direction.

Description

Moving Unit for Focus Ring and Apparatus for Treating Substrate}

The present invention relates to a focus ring moving unit that moves a focus ring in the horizontal direction and a substrate processing apparatus including the same.

Generally, the process of manufacturing a semiconductor device includes a deposition process to form a film on a semiconductor wafer (hereinafter referred to as a substrate), a chemical/mechanical polishing process to flatten the film, and a photoresist pattern to form a photoresist pattern on the film. A photolithography process, an etching process to form a film into a pattern with electrical characteristics using a photoresist pattern, an ion implantation process to inject specific ions into a predetermined area of the substrate, and cleaning to remove impurities on the substrate. It includes a process and an inspection process for inspecting the surface of the substrate on which the film or pattern is formed.

The etching process is a process for removing exposed areas of the photoresist pattern formed by the photolithography process on the substrate. Generally, types of etching processes can be divided into dry etching and wet etching.

The dry etching process forms an electric field by applying high-frequency power to the upper and lower electrodes installed at a predetermined distance in a sealed internal space where the etching process is performed, and applies an electric field to the reactive gas supplied into the sealed space to activate the reactive gas. After creating a plasma state, the ions in the plasma etch the substrate located on the lower electrode.

At this time, it is necessary to form plasma uniformly over the entire upper surface of the substrate. A focus ring is provided to uniformly form plasma over the entire upper surface of the substrate.

The focus ring is installed to surround an edge of the electrostatic chuck disposed on the lower electrode. An electric field is formed on the top of the electrostatic chuck by applying high-frequency power, and the focus ring greatly expands the area where the electric field is formed compared to the area where the substrate is located. The focus ring creates a plasma-sheath boundary near the periphery of the substrate. (plasma-sheath boundary) changes.

(Patent Document 1) KR 10-2021-0111872 A

The purpose of the present invention is to provide a focus ring movement unit capable of moving the focus ring without opening the chamber and a substrate processing apparatus including the same.

In order to solve the above object, the present invention provides a substrate processing apparatus including a focus ring moving unit and a focus ring moving unit as follows.

In one embodiment, the present invention includes a pin extending in a vertical direction to be inserted into a groove formed on the lower surface of a focus ring surrounding an electrostatic chuck; and a first moving unit connected to the pin and moving the pin in a horizontal direction.

In one embodiment, the focus ring moving unit is connected to the pin and may further include a second moving part that moves the pin in the height direction.

In one embodiment, the focus ring moving unit further includes a control unit connected to the first and second moving units, wherein the control unit operates the second driving unit when the focus ring is moved to insert the pin into the groove. After the focus ring is raised to a high level, the focus ring can be moved horizontally using the first driving unit.

In one embodiment, the present invention includes a chamber providing a processing space therein; an electrostatic chuck disposed within the chamber and supporting a substrate; a focus ring disposed to surround an outer periphery of the electrostatic chuck; a focus ring moving unit including a pin inserted into a groove formed on a lower surface of the focus ring; and a plasma generation unit for generating plasma within the chamber, wherein the focus ring moving unit is the focus ring moving unit described above.

In one embodiment, the focus ring includes an upper focus ring and a lower focus ring, a lower surface of the upper focus ring is in contact with an upper surface of the lower focus ring, and the lower focus ring includes a through hole through which the pin passes. In addition, the first and second moving parts may be disposed lower than the lower focus ring.

Through the above configuration, the present invention can provide a focus ring moving unit that can adjust the centering of the focus ring even during the process and a substrate processing device including the same, and can provide a substrate processing device for reworking and reworking due to miscentering of the focus ring. This process loss can be prevented by opening the chamber.

1 is a schematic diagram of a substrate processing apparatus according to an embodiment of the present invention.
Fig. 2 is a partial schematic diagram of the substrate processing apparatus of Fig. 1;
Figure 3 is an enlarged view of portion A of Figure 2.
4 is a schematic plan view of a substrate processing apparatus according to an embodiment of the present invention.
Figure 5 is a schematic diagram showing the operation of the focus ring moving unit in the substrate processing apparatus according to an embodiment of the present invention.
Figure 6 is a schematic plan view of a substrate processing apparatus according to another embodiment of the present invention.

Hereinafter, with reference to the attached drawings, preferred embodiments will be described in detail so that those skilled in the art can easily practice the present invention. However, when describing preferred embodiments of the present invention in detail, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description will be omitted. In addition, the same symbols are used throughout the drawings for parts that perform similar functions and actions. In addition, in this specification, terms such as 'upper', 'top', 'upper surface', 'lower', 'lower', 'lower surface', 'side', etc. are based on the drawings and are actually elements or components. It may vary depending on the direction in which it is placed.

In addition, throughout the specification, when a part is said to be 'connected' to another part, this does not only mean 'directly connected', but also 'indirectly connected' with another element in between. Includes. In addition, 'including' a certain component means that other components may be further included rather than excluding other components, unless specifically stated to the contrary.

1 and 2 show a schematic diagram of a substrate processing apparatus according to an embodiment of the present invention and a partial schematic diagram of the substrate processing apparatus of FIG. 1. A substrate processing apparatus according to an embodiment of the present invention includes a chamber 10, a plasma generation unit 20, and a substrate support assembly 30.

The chamber 10 provides a processing space therein for processing the substrate S. A film or pattern may be formed on the upper surface of the substrate S. The chamber 10 is provided to be sealable, and a passage 11 is formed in the side wall. The substrate S may be brought into the processing space within the chamber 10 through the passage 11, and the substrate S may be carried out from the processing space within the chamber 10. The passage 11 is configured to be opened and closed by a separate driving device (not shown). The chamber 10 can be grounded, and an exhaust hole 12 is formed at the bottom. The exhaust hole 12 is connected to an exhaust line (not shown) and a pump (not shown). Reaction by-products generated during the processing process and gas remaining in the inner space of the chamber 10 may be discharged to the outside through the exhaust hole 12. Through the exhaust process, the inside of the chamber 10 is depressurized to a predetermined pressure.

A liner 13 may be provided inside the chamber 10. According to the liner 13, the inside of the chamber 10 can be protected from by-products generated during the substrate processing process and gases remaining after the processing process. The liner 13 prevents impurities generated during the process from being deposited on the inner wall of the chamber 10 and/or the substrate support assembly 30. The liner 13 may include an inner liner provided in a ring shape to completely surround the substrate support assembly 30 and an outer liner provided along the inner wall of the chamber 10 .

The plasma generation unit 20 is located at the top of the inside of the chamber 10. The plasma generation unit includes a shower head 21, a gas supply nozzle 22, and an upper power source 23.

The shower head 21 is positioned at a certain distance from the top of the chamber 10 to the bottom. The shower head 21 is located on top of the substrate support assembly 30. A constant space is formed between the shower head 21 and the upper surface of the chamber 10, and the shower head 21 may be provided in the shape of a plate with a constant thickness. The shower head 21 includes a plurality of spray holes, and the spray holes penetrate the upper and lower surfaces of the shower head 21 in a vertical direction.

The gas supply nozzle 22 supplies process gas into the chamber 10. The gas supply nozzle 22 is connected to the central portion of the upper surface of the chamber 10 and receives gas from a gas storage unit (not shown) through a gas supply line (not shown) to supply process gas into the chamber 10. A nozzle is formed on the bottom of the gas supply nozzle 22, and the flow rate of the process gas supplied inside the chamber 10 can be adjusted using a separate valve (not shown) provided in the gas supply line (not shown). .

The upper power source 23 is electrically connected to the plasma generation unit 20 and provides power to the plasma generation unit 20. The upper power source 23 may be provided as a high-frequency power source or may be provided in a grounded manner. The plasma generation unit 20 may function as an upper electrode by receiving power from the upper power source 23.

The substrate support assembly 30 is disposed inside the chamber 10 to face the plasma generation unit 20 . The substrate support assembly 30 supports the substrate S. The substrate support assembly 30 includes an electrostatic chuck 100 that adsorbs the substrate S using electrostatic force. The substrate support assembly 30 may support the substrate S in various ways, such as mechanical clamping. In the present invention, a case where the substrate support assembly 30 supports the substrate S using the electrostatic chuck 100 will be described.

The substrate support assembly 30 includes an electrostatic chuck 100, a base 200, a focus ring 300, and a focus ring moving unit 400.

A substrate S may be mounted on the upper surface of the electrostatic chuck 100. The electrostatic chuck 100 has a disk shape and may be made of a dielectric substance. The upper surface of the electrostatic chuck 100 has a radius smaller than that of the substrate S. When the substrate S is placed on the electrostatic chuck 100, the edge area of the substrate S is located outside the electrostatic chuck 100. The electrostatic chuck 100 receives external power and applies electrostatic force to the substrate S. The electrostatic chuck 100 is provided with an electrostatic electrode 110. The electrostatic electrode 110 is electrically connected to an adsorption power source (not shown) including a direct current power source, and when a current is applied to the electrostatic electrode 110 from the adsorption power source (not shown), the electrostatic electrode 110 and the substrate (S ) Electrostatic force acts between the Accordingly, the substrate S is adsorbed to the upper surface of the electrostatic chuck 110.

The base 200 is provided at the lower part of the electrostatic chuck 100. The upper surface of the base 200 is in contact with the lower surface of the electrostatic chuck 100, and the base 200 is also provided in a disk shape. The base 200 is made of a conductive material. As an example, the base 200 may be made of aluminum. A cooling passage (not shown) may be provided inside the base 200 to cool the electrostatic chuck 100.

The base 200 may be electrically connected to the lower power source 210. The lower power source 210 may be provided as a high-frequency power source that generates high-frequency power, and the high-frequency power source may be provided as an RF power source. The base 200 may function as a lower electrode by receiving high frequency power from the lower power source 210. The base 200 may be provided grounded. When high-frequency power is applied to both the upper and lower electrodes in the chamber 10, or the upper electrode is grounded and high-frequency power is applied to the lower electrode, an electric field is generated between the upper and lower electrodes, and the generated electric field causes the chamber ( 10) The process gas provided inside is excited into a plasma state. The process gas excited in a plasma state may etch the substrate S.

The focus ring 300 is arranged to surround the outer periphery of the electrostatic chuck 100. The focus ring 300 includes an upper focus ring 310 and a lower focus ring 320. The lower surface of the upper focus ring 310 contacts the upper surface of the lower focus ring 320.

A focus ring moving unit 400 is disposed below the focus ring 300. The focus ring moving unit 400 includes a pin 410, a second moving part 430 that is connected to the pin 410 and moves the focus ring in the vertical direction, and moves the pin 410 through the second moving part 430. ) and a first moving part 420 that moves the pin 410 in the horizontal direction connected to the pin 410, and the first and second moving parts 420 and 430 are connected to the control part 380. The focus ring 300 and focus ring movement unit 400 will be described later with reference to FIGS. 3 and 4.

The focus ring 300 wears out as etching progresses. Accordingly, when the focus ring 300 is used for a certain period of time, the pin 410 is raised through the second moving part 430 to ensure uniform etching regardless of wear of the focus ring 300. The focus ring 300 is replaced after a certain period. At this time, the focus ring 300 is raised with the pin 410 and then replaced. When replacing, centering is performed so that the center matches the substrate (S), but there are cases where centering is not performed accurately due to product tolerances or errors in the focus ring moving robot. If centering is not performed accurately, problems may occur in the etching of the substrate (S), especially at the edges, so if centering is incorrect, rework must be performed. In some cases, centering may be performed again by opening the chamber (10). There are also cases where it is done.

In one embodiment, the present invention provides a focus ring moving unit 400 including a first moving unit 420 that moves the focus ring 300 in the horizontal direction, and the focus ring moving unit 400 is a focus ring moving unit 400. By moving the focus ring 300 in the horizontal direction while the focus ring 300 is seated, it is possible to perform centering of the focus ring 300 without breaking the process atmosphere, and as a result, no process interruption occurs. Productivity can be improved.

Additionally, by receiving feedback on the process results, the direction in which the focus ring 300 should move can be confirmed, and by moving the focus ring 300 in that direction, the process results can be improved.

The focus ring movement unit 400 is disclosed in more detail in FIGS. 3 and 4 .

FIG. 3 shows an enlarged view of portion A of FIG. 2 where the focus ring moving unit 400 is visible, and FIG. 4 shows a schematic plan view of the substrate processing apparatus.

As shown in FIG. 3, the focus ring moving unit 400 is located below the focus ring 300. Among the focus rings 300, the upper focus ring 310 has a groove 311 formed on its lower surface, and the end of the pin 410 can be inserted into the groove 311. The lower focus ring 320 has a through hole 321 formed at a position corresponding to the groove 311, and the pin 410 passes through the through hole 321.

The focus ring moving unit 400 extends in the vertical direction and includes a pin 410 that passes through the through hole 321 of the lower focus ring 320 and moves to the groove 311 of the upper focus ring 310, A second moving part 430 is connected to the pin 410 and moves the pin 410 in the vertical direction. It is connected to the pin 410 through the second moving part 430 and the second moving part 430 ) and a first moving part 420 that moves the pin 410 in the horizontal direction, for example, in the radial direction, and a control part 380 connected to the first and second moving parts 420 and 430. do.

The pin 410 extends in the vertical direction and moves vertically or horizontally according to the driving of the first and second moving parts 420 and 430. The pin 410 includes an end 411 inserted into the groove 311 of the upper focus ring 310 and a body 412. The body 412 is cylindrical with a constant diameter or has a diameter expanded in the middle. It may have an extension portion 413. The expansion portion 413 is disposed at a position corresponding to the through hole 421 of the lower focus ring 420.

In the groove 311 of the upper focus ring 310, the front and rear inner walls in the direction in which the first moving part 420 moves are formed parallel to the side of the pin 410, so that when the pin 410 moves, The upper focus ring 310 can be moved by pushing the inner wall of the groove 311. In other directions, it may have an inclined inner wall for ease of centering and insertion. The groove 311 may be formed to have a circular cross-section, and the diameter of the groove 311 may correspond to the diameter of the end 411 of the pin 410 or may have a slight gap for smooth inflow.

Meanwhile, the through hole 321 of the lower focus ring 320 may have a circular cross-section, and because the extension 413 of the pin 410 passes through it, it has a larger diameter than the extension 413. As shown in FIG. 3, the diameter (d) of the through hole 321 is larger than the diameter (a) of the expanded portion 413, and the diameter (d) of the through hole 321 and the diameter of the expanded portion 413 The difference in (a) is larger than the gap between the groove 311 and the end 411 of the pin 410.

The pin 410 is connected to the second moving part 430. The second moving part 430 is a linear moving means and can be an LM guide, a motor, a ball screw, a rack and pinion, or a linear motor, and any structure can be applied as long as it can perform precise and accurate linear motion. This second moving part 430 may be placed inside or below the base 200. The second moving unit 430 operates by receiving a signal from the control unit 380 to move the pin 410 in the vertical direction, that is, to raise and lower the pin 410. As mentioned above, the upper focus ring moves as wear progresses. The upper focus ring 310 is raised or lowered for replacement.

The first moving part 420 is a linear moving means similar to the second moving part 430, and can be an LM guide, a motor, a ball screw, a rack and pinion, or a linear motor, and is the same as the second moving part 430. It may be configured. In this embodiment, in the case of the first moving part 420, the second moving part 430 and the pin 410 are moved together along the radial direction. The second moving part 430 moves the second moving part 430 and the pin 410 within the difference between the diameter (d) of the through hole 321 and the diameter (a) of the expansion part 413. Therefore, a structure that allows precise movement can be applied.

In this embodiment, the first moving part 420 is described as moving the second moving part 430 and the pin 410, but it is not limited thereto, and the second moving part 430 moves the first moving part 430. It is possible to move the pin 420 and the pin 410 together, and it is also possible to move the pins 410 independently.

The focus ring moving unit 400 described above is provided at at least three positions below the focus ring 300. That is, focus ring moving units 400A, 400B, and 400C composed of a pin 410 and a set of first and second moving parts 420 and 430 are disposed below the focus ring 300. FIG. 4 shows three focus ring movement units 400A, 400B, and 400C arranged at an angle of 120 degrees with respect to the center C of the focus ring 300.

In each focus ring moving unit (400A, 400B, 400C), the first moving part 420 can move the pin 410 in the radial direction, so that the upper The focus ring 310 can be moved to a desired position in the horizontal direction. Typically, when centering is adjusted, the upper focus ring 310 is moved by tens of micrometers to several millimeters.

For example, when moving the upper focus ring 310 in the 12 o'clock direction in FIG. 4, the first moving part 420 of the focus ring moving unit 400A located at 11 o'clock and the focus ring moving unit located at 3 o'clock The upper focus ring 310 may be moved in the 12 o'clock direction by the operation of the first moving unit 420 of 400A. In this way, movement is possible in any direction by combining the first moving parts 420 of the three focus ring moving units 400A, 400B, and 400C.

Meanwhile, FIG. 5 shows a schematic diagram showing the operation of the focus ring movement unit 400 in the substrate processing apparatus according to an embodiment of the present invention.

As shown in FIG. 5(a), the control unit 380 moves the pin 410 to be positioned below the upper focus ring 300 when centering of the focus ring 300 is not necessary. As the pin 410 does not protrude, interference that may occur when setting the focus ring 300 is prevented and the problem of the focus ring 300 not being centered in the correct position occurs due to the pin 410 overprotruding. can be prevented. The downward position can be set by forming a protrusion (not shown) that catches the extension 413 in the through hole 321.

When centering of the focus ring 300, especially the upper focus ring 310, is required, that is, when horizontal movement of the upper focus ring 310 is required, as shown in FIG. 5 (b), the control unit 380 controls the second The moving unit 430 is operated. The second moving unit 430 raises the pin 410 so that the end 411 of the pin 410 enters the groove 311 of the upper focus ring 310.

When the pin 410 is raised enough for the end 411 of the pin 410 to enter the groove 311 of the upper focus ring 310, the control unit 380 stops the operation of the second moving unit 430, The first moving unit 420 is operated. The first moving unit 420 receives a signal from the control unit 380 and moves the upper focus ring 310 in the direction in which the upper focus ring 310 needs to be moved, for example, to the right in FIG. 5(c). I order it. Although only one pin 410 is shown in this drawing, a plurality of pins 410 can operate together to adjust the centering of the upper focus ring 310.

In the present invention, centering of the focus ring 300 can be performed with the chamber 10 closed, thereby increasing process efficiency.

Additionally, improved process results can be provided by analyzing process result data and fine-tuning the focus ring 300 in the horizontal direction.

FIG. 6 shows a plan view of a substrate processing apparatus including focus ring movement units 400A, 400B, and 400C according to another embodiment of the present invention. In this embodiment, the focus ring moving units 400A, 400B, and 400C include a first moving part 420 and a pin 410, and unlike the previous embodiment, they do not have a second moving part 430, Other configurations, for example, the configuration of the upper focus ring 310 and the lower focus ring 320, are the same.

In this embodiment, since the second moving part 430 is not provided, it is difficult to raise and lower the pin 410, but with a simple configuration, centering of the focus ring 300 can be achieved without opening the chamber.

This embodiment can also be used with a structure that has a lifting function for raising or replacing the upper focus ring 310 due to wear. That is, it is not excluded that additional components are added to the focus ring moving units 400A, 400B, and 400C including the first moving unit 420.

The above description has focused on embodiments of the present invention, but the present invention is not limited thereto and can of course be implemented in various modifications.

10: Chamber 20: Plasma generation unit
30: substrate support assembly 100: electrostatic chuck
200: Base 300: Focus Ring
310: upper focus ring 311: groove
320: Lower focus ring 321: Through hole
400, 400A, 400B, 400C: Focus ring movement unit
410: pin
411: end 412: body
413: expansion part 420: first moving part
430: second moving part

Claims (10)

a pin extending in the vertical direction to be inserted into a groove formed on the lower surface of the focus ring surrounding the electrostatic chuck; and
A focus ring moving unit comprising: a first moving unit connected to the pin and moving the pin in a horizontal direction. According to claim 1,
The focus ring moving unit is connected to the pin and further includes a second moving part that moves the pin in a height direction. According to claim 1,
The focus ring includes at least three grooves,
The first moving unit is configured to move the pin in a radial direction of the focus ring. According to claim 3,
The focus ring includes three grooves at 120° intervals,
A focus ring moving unit wherein the pin is disposed in each of the grooves. According to claim 4,
The first moving part moves the first moving part and the pin together,
A focus ring moving unit where the side of the singi pin is parallel to the inner wall of the groove. The method according to any one of claims 2 to 5,
Further comprising a control unit connected to the first and second moving units,
The control unit operates the second driving unit when the focus ring is moved to raise the pin to be inserted into the groove, and then moves the focus ring in the horizontal direction with the first driving unit. According to claim 6,
The control unit is a focus ring moving unit that raises all pins to be inserted into the grooves through a second driving unit when the focus ring is moved. According to claim 1,
The groove has a circular cross-section,
A focus ring moving unit wherein the diameter of the pin is smaller than the diameter of the groove. A chamber providing a processing space therein;
an electrostatic chuck disposed within the chamber and supporting a substrate;
a focus ring disposed to surround an outer periphery of the electrostatic chuck;
a focus ring moving unit including a pin inserted into a groove formed on a lower surface of the focus ring; and
It includes a plasma generation unit for generating plasma in the chamber,
The focus ring moving unit is a substrate processing apparatus that is the focus ring moving unit of any one of claims 2 to 5. According to clause 9,
The focus ring includes an upper focus ring and a lower focus ring,
The lower surface of the upper focus ring is in contact with the upper surface of the lower focus ring,
The lower focus ring includes a through hole through which the pin passes,
The first and second moving parts are disposed lower than the lower focus ring.

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