KR20080092766A - Substrate supporter and apparatus for plasma treatment having it - Google Patents

Abstract

A substrate supporter and a plasma process apparatus having the same are provided to secure stable reception of a substrate by reducing the generation possibility of arc discharge. At least one arm(21) receives a substrate(50). A supporting unit is extended to a position of the substrate receiving position. The supporting unit is formed with a supporting ring(22) that connects the arms. The supporting ring is formed to make an open contour. An auxiliary ring(22') is arranged on an opening of the open contour of the supporting ring. An auxiliary arm(21') is connected to the auxiliary ring. The auxiliary arm is formed to the same direction as the arm or the different direction. The auxiliary arm is individually driven with the arm. The supporting ring has plural supporting pins(23) that are extended to the substrate receiving direction. The supporting ring has a step where a slope is formed to the substrate direction. The supporting pin is formed on a lower portion of the step.

Description

Substrate supporter and apparatus for plasma treatment having it

1 is a cross-sectional view schematically showing a plasma processing apparatus according to an embodiment of the present invention,

2 is a view showing another embodiment of the substrate support of FIG.

3 is a partial perspective view of the substrate support of FIG. 1 and the substrate supported thereon;

4A is a variation of FIG. 3,

4B is another modification of FIG. 3,

5A is an enlarged view of a portion “A” of FIG. 4A;

5B is a view showing another example of FIG. 5A;

6a to 6c are views sequentially showing the operation of the substrate support according to an embodiment of the present invention,

7A-7D illustrate the operation of a plasma processing apparatus in accordance with an embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

1 ... plasma processing unit, 10 ... chamber,

20,80 ... substrate support, 21,81 ... arm,

30 ... first electrode, 40 ... second electrode,

50 ... substrate, 51 ... substrate front,

52 ... Back of substrate.

The present invention relates to a substrate support and a plasma processing apparatus having the same, and more particularly, a substrate for stably supporting a substrate such as a wafer on which a device having a predetermined thin film pattern is formed so as to remove various foreign substances formed on the back surface of the substrate. A support and a plasma processing apparatus having the same.

Semiconductor devices and flat panel display devices are formed by depositing and etching a plurality of thin films on a substrate. That is, a thin film is deposited on a predetermined region of the substrate, mainly a central portion, and a portion of the thin film of the central portion of the substrate is removed through an etching process using an etching mask to manufacture a device having a predetermined thin film pattern.

However, when the thin film is deposited, a thin film is formed on the entire surface of the substrate, and during etching, the thin film at the center of the substrate is used as an etching target, and thus the thin film is not removed at the edge of the substrate. Particles are deposited. In addition, the substrate support for supporting the substrate is usually mounted on the substrate support by electrostatic or vacuum force, so that the interface between the substrate and the substrate support is spaced a predetermined distance apart, thereby generating particles on the entire back surface of the substrate. And a thin film is deposited.

Therefore, when the continuous process is performed without removing the particles and the deposited thin film present in the substrate, many problems, such as the substrate is bent or the alignment of the substrate becomes difficult.

In general, methods for removing the particles and the deposited thin film are known as wet etching to remove particles on the surface by immersion in a solvent or rinse, and dry cleaning to remove the surface by etching with plasma.

Wet etching is effectively used to remove particles applied to the surface of the substrate, but it is difficult to manage the process locally, which makes it difficult to remove only the back side of the substrate, as well as cost increase due to the use of enormous chemicals and wastewater treatment. There is a problem that causes environmental problems, requires a long time processing, and the size of the equipment should be large. On the other hand, dry etching has an advantage of solving the above-described problem of wet etching by removing a thin film or particles on the substrate and the back surface using plasma.

Therefore, in recent years, the development of a dry etching apparatus for etching such a substrate back is actively being performed.

That is, a conventional plasma etching apparatus for etching the back surface of a substrate using the plasma as described above is disclosed in US Patent No. 5213650.

In US Patent No. 5213650, an apparatus including a vacuum chamber for forming a space between a plate and a front surface of a wafer to inject a reaction gas into the space, and generating a plasma on the back surface of the wafer to perform etching. Is disclosed.

In the above configuration, in order to support the wafer, when the substrate is supported by the lift pin method, the lift pin is disposed on the process region on the back surface of the substrate, which may cause electric discharge during the process. This can lead to process inhibition or substrate damage.

In addition, when supporting the substrate with a plurality of lift pins as described above, the supporting portion of the substrate, that is, the back surface of the substrate in contact with the lift pins is not etched, and when the process proceeds to a subsequent process without etching, There is a disadvantage that the parts that cause the defect of the product or not etched separately must be etched separately.

In addition, in the case of supporting the wafer with only the lower pin, it is not possible to guarantee stable seating of the wafer, and there is a possibility that the wafer is released on the pin when vibration or the like occurs.

The present invention has been made in order to solve the above problems, a substrate support for performing a quick etching using a small device as compared to the wet etching and to reduce the production cost while reducing the manufacturing cost and having the same It is an object to provide a plasma processing apparatus.

In addition, an object of the present invention is to provide a substrate support and a plasma processing apparatus having the same to increase the process yield and product stability by reducing the possibility of electrical discharge discharge compared to the conventional dry etching, to ensure a stable seating of the substrate do.

A substrate support according to the present invention comprises at least one arm configured to seat a substrate; And a support extending from the arm toward the substrate seating position.

Here, the arm is provided with at least three or more, characterized in that formed at right angles to each other based on the center of the substrate.

In addition, the support portion is formed of a support ring for interconnecting the arm, the support ring may be formed to form an open curve. In this case, an auxiliary ring disposed on the opening of the opening of the support ring and an auxiliary arm connected to the auxiliary ring may be provided, and the auxiliary arm may be formed in the same direction or in a different direction as the arm. It can be driven separately from the arm.

Further, the support ring has a plurality of support pins extending in the substrate mounting direction, the support ring has a stepped inclined toward the substrate, the support pin is formed below the step, the support The pin may extend from 1 to 3 mm in length from the end of the inclined step.

In this case, an upper portion of the support ring may be higher than a height of the upper portion of the substrate at the substrate seating position, and a protrusion of 0.5 to 1 mm orthogonal to an extension direction of the support pin on the support pin and toward the rear surface of the substrate is provided. It may be provided as.

Preferably, the protrusion is sharply formed in contact with the back surface of the substrate.

Plasma processing apparatus according to the present invention, the first electrode is a first gas is injected; A substrate support according to the present invention for supporting a substrate spaced apart from the first electrode; And a second electrode spaced apart from the substrate support, to which a power is applied and a second gas is injected to form a plasma between the substrate supported on the substrate support.

Here, the substrate support may be further provided with a driving means to adjust the separation distance with the first electrode, the arm of the substrate support is formed extending from the first electrode or extending from the second electrode Can be.

Hereinafter, a substrate support according to an embodiment of the present invention and a plasma processing apparatus having the same will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the embodiments are intended to complete the disclosure of the present invention, and to those skilled in the art to fully understand the scope of the invention. It is provided to inform you. Like reference numerals in the drawings refer to like elements.

1 is a cross-sectional view schematically showing a plasma processing apparatus according to an embodiment of the present invention.

Referring to FIG. 1, the plasma processing apparatus 1 according to the exemplary embodiment of the present invention may adjust the first electrode 30 to which the first gas is injected, and the first electrode 30 are spaced apart from each other, and the substrate 50 may be adjusted. Is spaced apart from the substrate support 20 supporting the substrate support 20 and the substrate support 20, and the power supply 70 is applied and the second gas is injected to the substrate 50 supported by the substrate support 20. It includes a second electrode 40 for forming a plasma.

In the embodiment of the present invention, the plasma processing apparatus 1 is an etching apparatus for generating a plasma to etch thin films and particles deposited on the back surface of a substrate 50 such as a wafer on which a device having a predetermined thin film pattern is formed.

The plasma processing apparatus 1 includes a chamber 10 formed to be openable and closeable through an opening and closing means 11 such as a gate valve and the like, and a conventional vacuum exhaust system 60 in communication with the chamber 10.

The chamber 10 may be a chamber 10 connected to the outside through at least one opening and closing means 11 and applied to a system composed of a plurality of chambers such as a cluster system or an inline system. In addition, the chamber 10 is configured to be grounded so that no current flows through the chamber 10.

The first electrode 30 may be disposed above the inside of the chamber 10, and the first electrode 30 may be connected to the ground. In addition, the first electrode 30 is formed with injection holes 33 for injecting non-reactive gas, and the injection holes 33 communicate with the supply holes 31 to supply the non-reactive gas from the outside of the chamber 10. It is composed.

Preferably, the entire surface of the surface on which the non-reactive gas of the first electrode 30 is injected into the first electrode 30 as much as possible, while the non-reactive gas supplied from the outside of the chamber 10 is supplied through one supply hole 31. A plurality of injection holes 33 are formed to be uniformly sprayed over, and a plurality of injection holes 33 branch from the supply holes 31 communicated with the inside of the first electrode 30.

If the injection hole 33 is formed in each of the supply hole 31 in the near and far, respectively, the diameter of the injection hole 33 formed in the remote is formed larger than the diameter of the injection hole 33 formed in the near, In the case of non-reactive gas injection, it is possible to compensate for the pressure drop due to the increased gas flow path.

In addition, a cooling passage 38 connected to the cooling water circulation means 37 configured outside the chamber 10 is provided in the first electrode 30.

The gas supplied through the supply hole 31 of the first electrode 30 may be hydrogen, nitrogen, or an inert gas, and may be other non-reactive gas, that is, gas that does not react with the front surface 51 of the substrate.

Here, the substrate front surface 51 may be a surface on which a device having a predetermined thin film pattern on a substrate 50 such as a wafer is formed, or may be a surface on which other substrates 50 are not etched.

The substrate 50 is spaced apart from the surface on which the injection hole 33 of the first electrode 30 is formed by a predetermined interval so that the front surface 51 faces the injection hole 33, and is supported by the substrate support 20. do.

The substrate support 20 is configured such that an arm 21 extending from an upper portion of the chamber 10 supports the substrate 50, and the arm 21 includes driving means configured in the substrate support 20 outside the chamber 10. It is configured to be stretchable by (not shown).

In order to maintain the vacuum tightness due to the configuration of the substrate support 20 to be stretchable by the drive means, the portion where the substrate support 20 exposed to the outside of the chamber 1 is connected to the drive means is a flexible bellows type. It is preferred to be configured.

The arm 21 of the substrate support 20 preferably supports only the outer edge portion of the substrate 50, and only a portion of the outer edge portion of the substrate back surface 52 supports the exposed area of the substrate back surface 52 as much as possible. Maximize.

The arm 21 is connected to the driving means to move up or down, i.e., close or distantly movable with respect to the first electrode 30, so that the substrate 50 supported thereon is also disposed close or distant with respect to the first electrode 30. Be sure to

Here, the substrate back surface 52 may be the other surface of the surface on which the device having a predetermined thin film pattern on the substrate 50 such as a wafer is formed, or may be a surface to which other substrates 50 are etched.

By the lifting and lowering motion of the arm 21, the front surface 51 of the substrate 50 maintains a predetermined gap d that is variable with respect to the surface on which the non-reactive gas of the first electrode 30 is injected.

In addition, the substrate support 20 is preferably configured to be electrically floating in the plasma processing apparatus 1 so as to be electrically non-interfering with other components, and the substrate support 20 including the arm 21. Is made of an insulating material such as Al ₂ O ₃ to prevent damage to the substrate support 20 by an external electric shock.

The second electrode 40 is disposed below the substrate support 20 at a predetermined distance D from the substrate support 20.

The second electrode 40 is configured to be applied to the power source 70, through which the injection hole 42 to be injected to the reactive gas.

Similar to that in the first electrode 30, the injection hole 42 is supplied with a reactive gas from the reactive gas supply means 44 through a supply hole 41 communicating with it from outside the chamber 1. It is configured to inject a reactive gas into the chamber (1), a plurality of toward the direction of the substrate back surface 52 such that a uniform reactive gas is injected over the entire surface of the back surface 52 of the substrate 50 supported by the substrate support 20 Dogs are formed.

In the injection hole 42 of the second electrode 40, the diameter of the injection hole 42 formed at a distance with respect to the portion where the supply hole 41 is formed is larger than the diameter of the injection hole 42 formed at a short distance, It is desirable to be able to compensate for the pressure drop due to the increased gas flow path during the reactive gas injection.

In addition to such a configuration, the gas injection structure in the first electrode 30 or the second electrode 40 can be variously changed as necessary.

On the other hand, the outer ring of the second electrode 40 is provided with an insulating ring 43 for concentrating the plasma generated on the second electrode (40). The insulating ring 43 may be made of an insulating material such as Al ₂ O ₃ .

The reactive gas injected through the injection hole 42 of the second electrode 40 may include a fluorine-based or oxygen-based gas such as CF ₄ , CHF ₄ , SF ₆ , C ₂ F _6, and C ₄ F ₈ . It may be a gas containing elements other than those capable of chemically etching thin films, particles, and the like deposited on the substrate back surface 52 of the substrate.

The second electrode 40 is configured to be capable of lifting and lowering, similar to that of the substrate support 20, by a driving means 49 separately configured outside the chamber 1, and supported by the substrate support 20. The distance D from the back surface 52 of the 50 to the second electrode 40 is configured to be variable.

In order to maintain the vacuum tightness due to the configuration of the second electrode 40 which can be moved up and down by the driving means 49, the second electrode 40 exposed outside the chamber 1 is connected to the driving means 49. The site to be joined is preferably composed of a stretchable bellows type.

In addition, a cooling passage 48 connected to the cooling water circulation means 47 configured outside the chamber 10 is provided in the second electrode 40. At this time, the cooling water circulation means 47 may be configured as the same member as the cooling water circulation means 37 for circulating the cooling water to the first electrode 30.

The power source 70 connected to the second electrode 40 may be a high frequency power having an integer multiple of 13.56 MHz, and other power sources may be used according to a desired process or device. At this time, the configuration of the high frequency power supply 70 connected to the second electrode 40 includes a matcher.

Due to the configuration of the second electrode 40 to which the grounded first electrode 30 and the high frequency power supply 70 are connected, the first electrode 30 serves as an anode and the second electrode 40 serves as a cathode. In addition, an alternating vibration of 13.56 MHz or 13.56 MHz is applied to the gas between the anode and the cathode to improve the plasma generation efficiency.

2 is a view showing another embodiment of the substrate support of FIG.

Unlike the substrate support 20 in FIG. 1 supporting the substrate 50 in a form in which the substrate 50 is suspended from the upper portion of the chamber 10, that is, the first electrode 30, the substrate support 80 is formed in the chamber (FIG. 10) is provided at the bottom to support the substrate 50.

The substrate support 80 in FIG. 2 also includes a driving means (not shown), and supports the substrate 50 by an arm 81 that can be lifted and lowered by the driving means. The front surface 51 of the substrate 50 maintains a predetermined gap d that is variable with respect to the surface on which the non-reactive gas of the first electrode 30 is injected by the lifting and lowering motion of the arm 81 through the driving means. Done.

In the case of the substrate support 80 as in FIG. 2, in the case of the substrate support 20 as in FIG. 1 as well, the arm 81 supports the outer edge of the substrate 50 to expose the exposed area of the substrate back surface 52. It is preferable to be configured so as to maximize the size, and other shapes of the same purpose are also possible.

In order to maintain the vacuum tightness due to the configuration of allowing the lifting and lowering movement by the driving means of the substrate support 80, it is preferable that the portion of the substrate support 80 exposed to the outside of the chamber 1 is configured to be elastic bellows type. Do.

3 is a partial perspective view of the substrate support of FIG. 1 and the substrate supported thereon.

The arm 21 of the substrate support 20 is connected with a driving means (not shown) to stretch it, and the arm 21 extends in the vertical downward direction.

The lower end of the arm 21 has a support portion formed in a direction perpendicular to the vertical lower direction, which is the extending direction of the arm 21, and the support member 21a as an example of the support portion supports each arm so as to support the substrate 50. FIG. It extends toward the inner direction which (21) makes.

In the present specification, the support is included as a component of the substrate support 20, and collectively refers to a member that supports and supports the substrate 50 directly.

Although one support member 21a is formed for one arm 21 to support the substrate 50, the exposed area of the substrate 50 is maximized, but two or more support members for one arm 21 are supported. 21a may be formed.

In this case, the support member 21a may support only a part of the outer edge portion of the substrate 50, and each support member 21a may be horizontal to each other to maintain the horizontality of the substrate 50.

Preferably, at least three arms 21 having the supporting member 21a are configured to support the substrate 50, and more preferably, each of the arms 21 is formed at an angle with respect to the center of the substrate 50. do.

Due to the support member 21a supporting a part of the outer back side of the substrate 50, the substrate 50 may be further exposed to the plasma etching region, unlike the conventional support of the substrate 50 by the lift pin. By supporting the outer periphery of the substrate 50 spaced from the center of the substrate 50 where the reaction is most active, an electric discharge phenomenon occurring during the process can be prevented, and the arm 21 is disposed outside the seating region of the substrate 50. In this way, the substrate 50 may be secured to be secured without leaving the process area.

4A is a modification of FIG. 3, and FIG. 4B is another modification of FIG. 3.

In FIG. 4A, each arm 21 is connected to form a support ring 22, and a support pin 23 is formed in the support ring 22 in the mounting direction of the substrate 50.

The support ring 22 is formed in a curved line with respect to the seating area of the substrate 50, and an auxiliary arm 21 ′ and an auxiliary ring 22 ′ formed therein are disposed in an empty section of the support ring 22. . Support pins 23 'may also be formed on the auxiliary ring 22'. Of course, the configuration of the support pin 23 ′ in the auxiliary ring 22 ′ may be omitted.

The tool gap of the support ring 22 formed by the open curve avoids the interference with the carrier 50 (not shown) such as the robot arm when the substrate 50 is seated and detached on the substrate support 20. In the process, the auxiliary arm 21 'is moved after the substrate 50 is seated to operate the auxiliary ring 22' and the support ring 22 to form a nearly closed curve.

The configuration of the support ring 22 is to improve the plasma uniformity formed near the substrate 50 during the plasma generation during the etching process, and is located between the tools of the support ring 22 in comparison with the configuration of FIG. 3. The auxiliary ring 22 'is also for improving the plasma uniformity.

In addition, the support ring 22 is a configuration for securing the substrate 50 mounting position when the substrate 50 is seated on the substrate support 20 so that the substrate 50 is stably seated, each arm Since the 21 is connected through the support ring 22, horizontality can be ensured when the substrate 50 is seated.

Accordingly, since the support ring 22 and the auxiliary ring 22 ′ bubble in the outer direction with respect to the substrate 50, the uniformity of the plasma formed on the back surface of the substrate 50 can be maintained.

The auxiliary arm 21 'on which the auxiliary ring 22' is formed may be formed in a direction opposite to the other arms 21, as shown in FIG. 4B, and other movable directions are possible.

Of course, in either case, the secondary arm 21 'preferably operates separately from the arm 21.

As in Fig. 3, in the configurations of Figs. 4A and 4B, only a part of the outer edge of the substrate 50 is contacted and supported, and as a result, the substrate 50 and the arm 21 come into contact with each other as far as possible from the plasma generation region, thereby generating electric arc discharge. It can be suppressed as much as possible.

The auxiliary arm 21 ′ supports the wafer substrate 50 carried by the robot arm when the substrate 50, such as a wafer, is seated on the substrate support 20 in a batch reactor such as a cluster system. It is configured to avoid mutual interference between the robot arm and the substrate support 20 in a series of movements to rest on the robot arm after being seated on the 20.

In other words, after the substrate 50 is conveyed by the robot arm in the tool-to-tool direction of the support ring 22 formed by the open curve, the robot arm is removed after the substrate 50 is seated on the substrate support 20. The auxiliary arm 21 'is disposed on the tool between the support ring 22 through the driving means, so that the support ring 22 and the auxiliary ring 22' together form a closed curve.

The auxiliary ring 22 'preferably has the same curvature as the curvature of the support ring 22, and more preferably, the support ring 22 and the auxiliary ring 22' have concentric curvatures. However, this is suitable when the substrate 50 is a substantially circular wafer, and other shapes may be possible depending on the shape of the substrate 50.

The auxiliary ring 22 'may be in contact with the support ring 22 to form a coupling in a conventional coupling method, for example, uneven coupling, magnetic coupling or male and female coupling.

Due to the arrangement of the auxiliary ring 22 ′, the substrate 50 may be more stably seated, and the separation of the substrate 50 from the substrate support 20 may be prevented even if vibration or the like occurs.

An accessory configuration of the substrate support 20, such as the support ring 22 or the auxiliary ring 22 ', may be composed of a solid solid such as metal or ceramic.

Of course, the configuration of the auxiliary ring 22 'may be omitted due to the substrate 50 or device 1 used, the required process, or the like.

FIG. 5A is an enlarged view of portion “A” of FIG. 4A.

A support pin 23 is formed in the support ring 22 of the arm 21, and the support pin 23 contacts and supports the substrate 50, and more specifically, a part of the outer edge of the back surface 52 of the substrate. .

In this case, the support pins 23 are formed to support at least three points of the substrate 50, and for this purpose, three or more arms 21 are provided. At this time, it is preferable that the arms 21 provided with three or more are formed at right angles with respect to the center of the substrate 50.

5B is a diagram illustrating another example of FIG. 5A.

As shown in FIG. 5B, the arm 21 of the substrate support 20 includes a support ring 22 having a predetermined step in which a slope 22a is formed, and the support pin 23 extends in the support ring 22. The support pin 23 has a protrusion 24 formed below the substrate 50, that is, toward the substrate back surface 52. The protrusion 24 is in direct contact with the substrate back surface 52 and is as sharp as possible to minimize the contact area with the substrate back surface 52.

The support pins 23 of the substrate support 20 are formed to support at least three or more points of the substrate 50, and have one or more protrusions 24 formed on one support pin 23 and the substrate back 52. And the second electrode 40 (FIG. 2) are formed so as not to interfere, that is, the substrate back surface 52 is exposed to the second electrode 40 as much as possible.

The support pins 23 having one protrusion 24 are preferably formed in a minimum number so that the back surface 52 of the substrate 52 can be exposed to the second electrode 40 as much as possible. Although it may be formed, it is difficult to maintain the horizontal support of the substrate 50 when supporting two points, more preferably formed to support three or more points.

At this time, it is preferable that the points at which the support pins 23 having the protrusions 24 support the substrate 50 are respectively conformal.

The support pin 23 extending from the support ring 22 and the protrusion 24 provided on the support pin 23 are provided on the substrate 50 side of the upper support ring 22, that is, the point where the inclination 22a starts. A distance between the substrate 50 and the outer periphery of the substrate 50, a distance b between the support pin 23 and the substrate back surface 52, and a vertical height c from the top of the support ring 22 to the substrate front surface 51. Have Compared with the configuration of FIG. 5A in FIG. 5B, in FIG. 5A, the distance b between the support pin 23 and the substrate back surface 52 is zero due to the configuration of the protrusion 24.

The support ring 22 is formed to form an inclination 22a of a predetermined angle from an upper end to a support end 23 of the support pin, and forms a distance a between the support ring 22 and the outer periphery of the substrate 50 to form a front surface of the substrate ( The flow of the first gas injected toward 51 is directed to the substrate back surface 52.

The gap a between the support ring 22 and the outer circumference of the substrate 50 is not smoothly flowed when excessively narrowed, and when the substrate 50 is seated on the substrate support 20, the substrate support ( Since physical interference between the substrate 20 and the substrate 50 may be caused, it is preferably 3 mm or more.

The support pin 23 extends from the support ring 22 toward the substrate 50 and is integrally formed with the support ring 22.

The support pin 23 preferably extends from the bottom of the inclined 22a of the support ring 22 to a length of about 1 mm. If the length of the support pins 23 is too short, it is difficult to stably support the substrate 50. If the length of the support pins 23 is too long, the support pins 23 may be separated from the back surface 52 of the substrate and the second electrode 40. Since the excessive interference and the efficiency of the equipment and the process implemented by the equipment can be reduced, the length of the support pin 23 is suitably 1 to 3 mm.

The distance b between the support pin 23 and the substrate back surface 52 is defined by the protrusion 24 provided at one end of the support pin 23 to face the first electrode 30, that is, upward. Can be done. In addition, when the substrate 50 to be used has a constant thickness, such as a wafer, the vertical height c from the top of the support ring 22 to the front surface 51 of the substrate may also depend on the size of the protrusion 24. .

The protrusion 24 is formed to support the back surface 52 of the substrate from the support pins 23, and is formed as sharp as possible to maximize the degree of exposure of the back surface 52 of the substrate. The protrusion 82 is formed to have a height of 0.5 to 1 mm from the arm 81, and because of the height of the protrusion 24, the distance b between the support pin 23 and the substrate back surface 52 is also 0.5. To 1 mm.

In the case where the protrusion 24 is less than 0.5 mm, the narrow space b between the substrate 50 and the support pin 23 may inhibit the flow of gas, in particular the flow of the second gas, and may exceed 1 mm. At the time, the protrusion 24 may be damaged due to the configuration of the sharp protrusion 24.

The vertical height c from the upper side of the support ring 22 to the substrate front surface 51 is a value that can be dependent on the height of the protrusion 24 and the thickness of the substrate 50. ) Is 0, that is, the upper portion of the support ring 22 and the substrate front surface 51 have the same height, or a negative value, that is, the substrate front surface 51 is located at an altitude lower than the upper portion of the support ring 22. Do.

When the substrate front surface 51 is located at an altitude higher than the upper portion of the support ring 22, when vibration or the like is applied from the outside, there is a high probability that the substrate 50 is separated from the seating position of the substrate support 20, It is not a desirable structure. Therefore, the substrate front surface 51 is preferably located at an altitude equal to or lower than the upper portion of the support ring 22.

As such, the structure of the substrate support 20 which minimizes the contact with the substrate 50 at the position away from the center of the process region suppresses phenomena such as electric discharge generated during the process, thereby improving process stability and damaging the substrate. Can be prevented in advance.

Such a structure of the substrate support 20 can also be applied to the substrate support 80 in FIG. 2 or the substrate support 20 in FIG. 3.

In addition, the auxiliary ring 22 ′ in FIGS. 4A and 4B may have a configuration of a support pin 23 or a protrusion 24 having the same structure as in FIG. 5A or 5B.

6A through 6C are views sequentially showing operations of the substrate support according to the embodiment of the present invention. The substrate support in this embodiment may be the same as the operation of the substrate support 20 having the structure as shown in FIG. 4B, the substrate support 80 having the structure as shown in FIG. 4A, or the substrate support having the structure other than the same. Can be.

Referring to FIG. 6A, the arm 21 moves to a predetermined position and is fixed to the substrate support 20.

Subsequently, as shown in FIG. 6B, the substrate 50 is transferred through a separate vehicle (not shown) onto the substrate support 20, and the substrate 50 is seated on the support pin 23. At this time, the support pin 23 may be a support pin 23 having a structure as shown in FIG. 5A, and may be a support pin 23 having a protrusion 24 as shown in FIG. 5B.

At this time, the transfer of the substrate 50 is performed in the direction of the arrow between the tool of the substrate support 20 in order to avoid interference between the vehicle and the substrate support 20, the vehicle is an arrow after the substrate 50 is seated Evicted in the opposite direction.

After the vehicle is evicted from the substrate support 20, as shown in FIG. 6C, the auxiliary arm 21 ′ moves up from the lower portion of the substrate support 20 to the tool formed by the support ring 22 to support the support ring 22. ) And the auxiliary ring (22 ') make almost a closed section. At this time, the support pins 23 and 23 'are preferably horizontal.

Through the operation of the substrate support 20 as described above, the substrate 50 is seated on the substrate support 20.

Hereinafter, the operation of the plasma processing apparatus 1 having the substrate support 20 operated as described above will be described with reference to FIGS. 7A to 7D. However, in FIGS. 7A to 7D, the substrate support 80 as shown in FIG. 2 will be described as an example, but the operation in the substrate support other than the embodiments presented herein will be similar.

7A to 7D are diagrams sequentially illustrating the operation of the plasma processing apparatus according to the exemplary embodiment of the present invention. In particular, FIG. 7D illustrates a gas flow path during substrate processing as arrows.

Operation of the plasma processing apparatus 1 in the embodiment of the present invention is an etching method for etching the thin film and particles deposited on the back surface of the substrate 50 such as a wafer on which a device having a predetermined thin film pattern is formed by generating a plasma. .

The operation of the plasma processing apparatus 1 according to the embodiment of the present invention allows the substrate 50 to be placed on the substrate support 80 between the first electrode 30 and the second electrode 40 in the plasma processing apparatus 1. A substrate seating step of seating on the substrate, a substrate fixing step of fixing the seated substrate 50, a first gas being injected onto the first surface 51 of the fixed substrate 50, and the second surface 52. And a gas processing step of injecting a second gas onto the substrate and a substrate processing step of applying a power source 70 to the injected second gas to form a plasma to process the second surface 52 of the substrate 50.

As shown in FIG. 7A, the substrate 50 is introduced by a conveying means (not shown) through an inlet provided in the chamber 1 and is seated on the substrate support 80. The substrate 50 supported on the substrate support 80 has a front surface 51 facing the injection hole 33 of the first electrode 30 and a rear surface 52 the injection hole 42 of the second electrode. It is arranged to face.

In this case, the substrate support 80 may be the substrate support 20 described with reference to FIG. 1.

In any case, the substrate support 80 is in a retracted position with a gap d ′ with respect to the first electrode 30, and the second electrode 40 is also spaced D ″ with respect to the first electrode 30. In the retracted position.

Subsequently, as illustrated in FIGS. 6A to 6C, the substrate 50 is seated on the substrate support 80.

As shown in FIG. 7B, when the chamber 1 is sealed and the vacuum is formed through the opening and closing means 11, the substrate support 80 is moved upward by the driving means (not shown) to allow the substrate front surface 51 and the first electrode. Let 30 make the gap d (d <d '). As the substrate support 80 is raised to decrease the gap d between the first electrode 30 and the front surface 51 of the substrate, the distance D ″ between the second electrode 40 and the substrate back surface 52 is also increased. The gap D 'is widened.

Thereafter, as shown in FIG. 7C, the second electrode 40 is also moved upward by the driving means 49 so that the substrate back surface 52 and the second electrode 40 form a gap D (D <D '). ).

The gap d between the first electrode 30 and the substrate 50 or the distance D between the substrate 50 and the second electrode 40 may be the substrate support 80 as described in the embodiment of the present invention. And the lifting and lowering motion of the second electrode 40 may be achieved by driving at least two members of the first electrode 30, the substrate support 80, and the second electrode 40. To this end, separate driving means may be provided in each member.

In addition, the distance D between the second electrode 40 and the back surface 52 of the substrate does not necessarily need to be variable, and any distance D, D ', or D is enough to generate a plasma within the distance D. It may be possible, and accordingly, the process may be performed after only the substrate support 80 is moved without moving the second electrode 40.

Of course, gaps other than the gaps D, D ', and D "shown in the drawings are also possible, and the gap between the substrate support 80 and the second electrode 40 varies depending on the required process, chamber or substrate size. Of course, it may be possible and may vary during the process.

Thereafter, as shown in FIG. 7D, non-reactive gas is first introduced through the first electrode 30, and then reactive gas is introduced through the second electrode 40, and power is applied through the high frequency power supply 70. Gas plasma is generated.

The reactive gas plasma is formed in the plasma generation region, and the radicals in the plasma react with the thin film or particles deposited on the substrate back 52 to detach them from the substrate back 52, thereby performing an etching process.

At this time, the plasma is formed in the gap D between the substrate back surface 52 and the second electrode 40, and the gap d between the first electrode 30 and the substrate front surface 51 is caused by the inflow of the non-reactive gas. This results in only non-plasma gas flows.

At this time, the gap d is preferably 0.1 to 0.7 mm. When the gap d is less than 0.1 mm, there is a possibility of contact with the first electrode 30, and it is necessary to maintain the gap d of 0.1 mm or more in order to perform a more stable process. In the gap d exceeding 0.7 mm, the pressure of the non-reactive gas decreases relatively, so that radicals formed in the gap D can flow into the gap d to etch the substrate front surface 51, so that the gap d Silver is preferably 0.7 mm or less. In addition, in the gap exceeding 0.7 mm, plasma formation of the non-reactive gas may proceed, and thus, the substrate front surface 51 may be etched. However, in the gap d of 0.7 mm or less, the process pressure in the conventional etching process and The area where the plasma is not generated by the process voltage may be maintained.

In addition, the non-reactive gas injected from the first electrode 30 has a higher dielectric breakdown voltage than the reactive gas injected from the second electrode 40, and plasma is not generated by the power applied to the second electrode 40. It is preferable not to.

The reactive gas injected from the second electrode 40 may be a gas containing oxygen or a highly reactive group 7 element series such as fluorine, such as CF ₄ , CHF ₄ , SF ₆ , C ₂ F _6, and C ₄ F _8. It may be a gas containing other element species that can be etched according to the type of thin film or particles deposited on the substrate back surface 52 to be used.

When the plasma is formed of the reactive gas, radicals of the elements are generated to react with the etching target element on the back surface 52 of the substrate to have high activity, thereby performing etching.

A separate confining magnetic field may be further formed to limit the plasma region, and the confining magnetic field may be formed of a permanent magnet, an electromagnet, or an induction magnetic field. In some cases, vibration of the ions in the plasma may be caused by magnetic force to further improve the plasma generation efficiency. In this case, the magnetic field may be formed differently depending on the shape of the chamber 10, the substrate 50, the first electrode 30, or the second electrode 40.

In addition, a power source 70 for applying power to the second electrode 40 may be a direct current, an alternating current, or the like, in addition to a high frequency power source. In this case, the electrical connection of the first electrode 30 or the second electrode 40 may vary according to the power source used, and a separate member for applying power may be further provided.

When the etching is finished, the power supply is stopped, the supply of reactive gas and non-reactive gas is cut off, and the etching by-products are removed in the chamber 10 through vacuum exhaust. At this time, the etching byproduct is in the form of a gas reacted with the radicals of the plasma, and thus can be sufficiently removed by vacuum exhaust.

When the etching by-products are removed, the second electrode 40 is lowered through the driving means 49, and the substrate 50 is removed from the first electrode 30 through the driving means of the substrate support 20.

Thereafter, the vacuum is discarded, the opening and closing means 11 is opened, and the etching process is completed by drawing the substrate 50 by the transfer means.

Although the technical spirit of the present invention has been described in detail according to the above-described preferred embodiment, it should be noted that the above-described embodiment is for the purpose of description and not of limitation. In addition, those skilled in the art will understand that various embodiments are possible within the scope of the technical idea of the present invention.

By the substrate support and the plasma processing apparatus having the same according to the present invention as described above, it is possible to quickly perform the etching by using a small device compared to the wet etching and to reduce the production cost while preventing the environmentally hazardous waste. .

In addition, the substrate support and the plasma processing apparatus having the same according to the present invention can reduce the possibility of electrical discharge discharge compared to the conventional dry etching to increase the process yield and product stability, and to ensure a stable mounting of the substrate.

Claims (18)

At least one arm configured to seat the substrate; And A support extending from the arm toward the substrate seating position; Substrate support comprising a. The substrate support of claim 1, wherein at least three arms are provided. The substrate support of claim 2, wherein the arms are formed at right angles with respect to the center of the substrate. The substrate support of claim 1, wherein the support is formed by a support ring interconnecting the arms. The substrate support of claim 4, wherein the support ring is formed to have an open curve. 6. The substrate support according to claim 5, wherein an auxiliary ring arranged on an opening of the open curve of the support ring and an auxiliary arm connected to the auxiliary ring are provided. The substrate support according to claim 4 or 6, wherein the auxiliary arm is formed in the same direction or in a different direction from the arm. 7. The substrate support of claim 6, wherein the auxiliary arm is driven separately from the arm. The substrate support of claim 4, wherein the support ring has a plurality of support pins extending in the substrate seating direction. The substrate support of claim 9, wherein the support ring has a stepped inclination toward the substrate, and the support pin is formed below the stepped. 10. The substrate support according to claim 9, wherein the support pin extends in a length of 1 to 3 mm from an end of the inclined step. The substrate support of claim 9, wherein an upper portion of the support ring is higher than a height of the upper portion of the substrate at the substrate seating position. 10. The substrate support of claim 9, wherein a protrusion is formed on the support pin to be perpendicular to the extending direction of the support pin and toward the rear surface of the substrate. The substrate support of claim 13, wherein the protrusion is formed at a height of 0.5 to 1 mm. The substrate support according to claim 13, wherein the protrusion is sharply formed in contact with the rear surface of the substrate. A first electrode to which the first gas is injected; A substrate support according to any one of claims 1 to 15 spaced apart from the first electrode to support a substrate; And A second electrode spaced apart from the substrate support and configured to form a plasma between the substrate supported on the substrate support by applying power and injecting a second gas; Plasma processing apparatus comprising a. 17. The plasma processing apparatus of claim 16, wherein the substrate support further comprises a driving means to adjust a separation distance from the first electrode. The plasma processing apparatus of claim 16, wherein the arm of the substrate support extends from the first electrode or extends from the second electrode.

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