KR20230103859A - Lift pin unit and Unit for supporting substrate and substrate processing apparatus - Google Patents

Abstract

A substrate support unit is disclosed. The substrate support unit according to an embodiment of the present invention includes: a susceptor that supports a substrate and has pinholes formed in a vertical direction; and a lift pin unit for loading and unloading the substrate on the susceptor. The lift pin unit includes a lift pin provided to move up and down along the pinhole; a support part moved up and down by a driving part; and a pin holder connecting the support part and the lift pin. The lift pin is connected to the pin holder to be pivotable about the vertical central axis of the pinhole. The pin holder may be connected to the support part to enable horizontal movement. Therefore, it is possible to flexibly cope with thermal deformation (shrinkage) of the substrate support unit.

Description

Lift pin unit, substrate support unit having the same, and substrate processing apparatus

The present invention relates to a lift pin unit for seating a substrate on an upper portion of a substrate support and a substrate support unit including the same

In general, plasma refers to an ionized gaseous state composed of ions, radicals, and electrons. Plasma is generated by very high temperatures, strong electric fields, or RF Electromagnetic Fields. A semiconductor device manufacturing process may include an etching process of removing a thin film formed on a substrate such as a wafer using plasma. The etching process is performed when ions and/or radicals of the plasma collide with or react with the thin film on the substrate.

When processing a substrate using plasma, the linearity of ions and/or radicals included in the plasma is important. Linearity of ions and/or radicals included in plasma acts as an important factor in determining the selectivity of a substrate. When processing a substrate to improve the linearity of ions and/or radicals, the temperature of an electrostatic chuck supporting the substrate is made very low.

In the cryogenic plasma apparatus that performs plasma processing in a cryogenic environment of -30 degrees or less, contraction occurs because the substrate support unit is brought to cryogenic temperature by the refrigerant flowing therein, and great stress is also generated in the tightening and fixing parts of the lift pins. This causes serious problems in the operation of equipment, such as damage.

One object of the present invention is to provide a lift pin unit capable of flexibly coping with thermal deformation (shrinkage) of the substrate support unit, a substrate support unit including the lift pin unit, and a substrate processing apparatus.

The object of the present invention is not limited thereto, and other objects not mentioned will be clearly understood by those skilled in the art from the following description.

According to one aspect of the present invention, the susceptor supporting the substrate, the pinhole is formed in the vertical direction; A lift pin unit for loading and unloading a substrate on the susceptor; The lift pin unit may include a lift pin provided to move up and down along the pinhole; a support that is moved up and down by a driving unit; including a pin holder connecting the support portion and the lift pin; A substrate support unit may be provided in which the lift pin is connected to the pin holder to be pivotally rotatable with respect to a vertical central axis of the pinhole, and the pin holder is connected to the support unit to be movable in a horizontal direction.

The lift pin may include a joint ball, and the pin holder may include a ball socket into which the joint ball is inserted and a ball socket capable of pivoting the lift pin in a shape surrounding the joint ball.

The lift pin unit may further include a first elastically deformable member that elastically deforms when the joint ball pivots and provides a return force to bring the lift pin back to its original position with respect to a vertical central axis.

In addition, the first elastically deformable member may include a pin-shaped first connection pin having an elastic restoring force, one end inserted into the first insertion groove of the joint ball and the other end inserted into the second insertion groove of the ball socket. can

In addition, the first insertion groove and the second insertion groove may be provided on a straight line with the vertical central axis.

The lift pin unit may further include a second elastically deformable member that is elastically deformed when the pin holder is horizontally moved and provides a return force to return the pin holder to its original position before horizontal movement.

In addition, the second elastically deformable member has an elastic restoring force, one end is inserted into the third insertion groove formed on the bottom surface of the pin holder, and the other end is inserted into the fourth insertion groove formed on the upper surface of the support portion of the pin shape. 2 connection pins may be included.

In addition, the third insertion groove and the fourth insertion groove may be provided on the same vertical line.

According to another aspect of the present invention, a lift pin inserted into the pinhole; a support that is moved up and down by a driving unit; including a pin holder connecting the support portion and the lift pin; The lift pin is connected to the pin holder so as to be pivotally rotatable about a vertical central axis of the pinhole; The lift pin may include a joint ball, and the pin holder may include a ball socket into which the joint ball is inserted and a ball socket capable of pivoting the lift pin in a shape surrounding the joint ball. .

The lift pin unit may further include a first elastically deformable member that elastically deforms when the joint ball pivots and provides a return force to bring the lift pin back to its original position with respect to a vertical central axis.

In addition, the first elastically deformable member may include a pin-shaped first connection pin having an elastic restoring force, one end inserted into the first insertion groove of the joint ball and the other end inserted into the second insertion groove of the ball socket. can

In addition, the pin holder is connected to the support to be movable in a horizontal direction; The lift pin unit may further include a second elastically deformable member that is elastically deformed when the pin holder is horizontally moved to provide a return force to return the pin holder to its original position before the horizontal movement.

In addition, the second elastically deformable member has an elastic restoring force, one end is inserted into the third insertion groove formed on the bottom surface of the pin holder, and the other end is inserted into the fourth insertion groove formed on the upper surface of the support portion of the pin shape. 2 connection pins may be included.

In addition, the pin holder may include an upper holder connected to the lift pin and a lower holder connected to the support, and the upper holder and the lower holder may be coupled to each other using a bolt method.

According to another aspect of the present invention, a process chamber forming a process space; a gas supply unit supplying a process gas into the process chamber; a plasma generating unit generating plasma from the process gas introduced into the process chamber; a substrate support unit provided in the processing space and supporting a substrate, the substrate support unit comprising: a dielectric plate having an electrostatic electrode adsorbing the substrate by electrostatic force; an electrode plate provided under the dielectric plate and having a passage through which a refrigerant flows; an annular focus ring provided around the dielectric plate; an insulator plate provided under the electrode plate and made of an insulator; a base plate provided under the insulator plate and grounded; Including a lift pin unit provided in the inner space of the base plate; The lift pin unit may include a lift pin inserted into a pin hole penetrating the dielectric plate, the electrode plate, and the insulator plate; a support that is moved up and down by a driving unit; including a pin holder connecting the support portion and the lift pin; The lift pin may be connected to the pin holder to be pivotally rotatable about a vertical central axis of the pinhole, and the pin holder may be connected to the support to be movable in a horizontal direction.

In addition, the lift pin includes a joint ball, the pin holder includes a ball socket into which the joint ball is inserted, and a ball socket capable of pivoting the lift pin in a shape surrounding the joint ball, and the lift pin unit The joint ball may further include a first elastically deformable member that is elastically deformed when the joint ball pivots and provides a return force to return the lift pin to its original position toward the vertical central axis.

The lift pin unit further includes a second elastically deformable member that is elastically deformed when the pin holder is horizontally moved to provide a return force to return the pin holder to its original position before horizontal movement; The second elastically deformable member has an elastic restoring force, one end is inserted into the third insertion groove formed on the bottom surface of the pin holder, and the other end is inserted into the fourth insertion groove formed on the upper surface of the support unit. May contain pins.

In addition, the substrate processing apparatus may process the substrate using cryogenic plasma.

According to the present invention, it is possible to flexibly cope with thermal deformation (shrinkage) of the substrate support unit and prevent damage to the lift pins.

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

1 is a diagram schematically showing a substrate processing apparatus according to an embodiment of the present invention.
Figure 2 is a cross-sectional view showing the process module shown in Figure 1;
3 is a view showing a pinhole.
FIG. 4 is an enlarged view of a main part shown in FIG. 2 .
5 is a cross-sectional view showing a coupled state between the lift pin and the pin holder in FIG. 4 .
6 is an exploded perspective view for explaining the lift pin and the pin holder of FIG. 5;
7A and 7B are views showing that the lift pin is returned to its original position along the vertical central axis (C) by the first and second elastic deformable members.

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily carry out the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. In addition, in 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 subject matter of the present invention, the detailed description will be omitted. In addition, the same reference numerals are used throughout the drawings for parts having similar functions and actions.

'Including' a certain component means that other components may be further included, rather than excluding other components unless otherwise stated. Specifically, terms such as "comprise" or "having" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features or It should be understood that the presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded.

Singular expressions include plural expressions unless the context clearly dictates otherwise. In addition, shapes and sizes of elements in the drawings may be exaggerated for clearer description.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms may be used for the purpose of distinguishing one component from another. For example, a first element may be termed a second element, and similarly, the second element may also be termed a first element, without departing from the scope of the present invention.

It is understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, but other elements may exist in the middle. It should be. On the other hand, when a component is referred to as “directly connected” or “directly connected” to another component, it should be understood that no other component exists in the middle. Other expressions describing the relationship between components, such as "between" and "directly between" or "adjacent to" and "directly adjacent to", etc., should be interpreted similarly.

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

The above detailed description is illustrative of the present invention. In addition, the foregoing is intended to illustrate and describe preferred embodiments of the present invention, and the present invention can be used in various other combinations, modifications, and environments. That is, changes or modifications are possible within the scope of the concept of the invention disclosed in this specification, within the scope equivalent to the written disclosure and / or within the scope of skill or knowledge in the art. The written embodiment describes the best state for implementing the technical idea of the present invention, and various changes required in the specific application field and use of the present invention are also possible. Therefore, the above detailed description of the invention is not intended to limit the invention to the disclosed embodiments. Also, the appended claims should be construed to cover other embodiments as well.

In an embodiment of the present invention, a substrate processing apparatus for etching a substrate using plasma will be described. However, the present invention is not limited thereto and can be applied to various types of devices that perform a process by supplying plasma into a chamber.

Referring to FIG. 1 , a substrate processing apparatus 1 includes an index module 10 , a loading module 30 , and a process module 20 .

The index module 10 may include a load port 120, a transfer frame 140, and a buffer unit 2000, and the load port 120, the transfer frame 140, and the process module 20 sequentially can be arranged in a row.

Hereinafter, the direction in which the load port 120, the transfer frame 140, the loading module 30, and the process module 20 are arranged is referred to as a first direction 12, and when viewed from above, the first direction ( 12) is referred to as a second direction 14, and a direction perpendicular to the plane including the first direction 12 and the second direction 14 is referred to as a third direction 16.

A carrier 18 accommodating a plurality of substrates W is seated in the load port 120 . A plurality of load ports 120 are provided and they are arranged in a line along the second direction 14 . The carrier 18 is formed with slots (not shown) provided to support the edge of the substrate. A plurality of slots are provided in the third direction 16, and the substrates are placed in the carrier in a stacked state spaced apart from each other along the third direction 16. A front opening unified pod (FOUP) may be used as the carrier 18 .

The transfer frame 140 transfers the substrate W between the carrier 18 seated in the load port 120 , the buffer unit 2000 , and the loading module 30 . An index rail 142 and an index robot 144 are provided on the transfer frame 140 . The length direction of the index rail 142 is parallel to the second direction 14 . The index robot 144 is installed on the index rail 142 and linearly moves in the second direction 14 along the index rail 142 . The index robot 144 has a base 144a, a body 144b, and an index arm 144c. The base 144a is installed to be movable along the index rail 142 . The body 144b is coupled to the base 144a. The body 144b is provided to be movable along the third direction 16 on the base 144a.

In addition, the body 144b is provided to be rotatable on the base 144a. The index arm 144c is coupled to the body 144b and is provided to be movable forward and backward with respect to the body 144b. A plurality of index arms 144c are provided to be individually driven. The index arms 144c are stacked and spaced apart from each other along the third direction 16 . Some of the index arms 144c are used when transferring the substrate W from the process module 20 to the carrier 18, and some of the index arms 144c transfer the substrate W from the carrier 18 to the process module 20. can be used when This can prevent particles generated from the substrate W before processing from being attached to the substrate W after processing during the process of carrying in and unloading the substrate W by the index robot 144 .

The buffer unit 2000 temporarily stores the substrate W. The buffer unit 2000 performs a process of removing process by-products remaining on the substrate W. The buffer unit 2000 performs a post-processing process of post-processing the substrate W processed in the process module 20 . The post-processing process may be a process of purging a purge gas on the substrate W. A plurality of buffer units 2000 are provided. Each buffer unit 2000 is positioned to face each other with the transfer frame 140 interposed therebetween. The buffer units 2000 are arranged in the second direction 14 . They are located on both sides of the transfer frame 140, respectively. Optionally, the buffer unit 2000 is provided singly and may be located on one side of the transfer frame 140 . The loading module 30 is disposed between the transport frame 140 and the transport unit 240 . The loading module 30 replaces the normal pressure atmosphere of the index module 10 with the vacuum atmosphere of the process module 20 for the substrate W carried into the process module 20 or the substrate W carried into the index module 10. Regarding (W), the vacuum atmosphere of the process module 20 is replaced with the normal pressure atmosphere of the index module 10. The loading module 30 provides a space in which the substrate W stays between the transfer unit 240 and the transfer frame 140 before the substrate W is transported. The loading module 30 includes a load lock chamber 32 and an unload lock chamber 34 .

In the load lock chamber 32 , a substrate W transferred from the index module 10 to the process module 20 is temporarily stored. The load lock chamber 32 maintains an atmospheric pressure atmosphere in a standby state, and is blocked from the process module 20 while maintaining an open state from the index module 10 . When the substrate W is loaded into the load lock chamber 32 , the internal space is sealed for each of the index module 10 and the process module 20 . Thereafter, the internal space of the load lock chamber 32 is replaced from a normal pressure atmosphere to a vacuum atmosphere, and is opened to the process module 20 in a closed state to the index module 10 .

In the unload lock chamber 34 , the substrate W transported from the process module 20 to the index module 10 temporarily stays. The unload lock chamber 34 maintains a vacuum atmosphere in the standby state, and is blocked from the index module 10 while maintaining an open state from the process module 20 . When the substrate W is loaded into the unload lock chamber 34, the internal space is sealed for each of the index module 10 and the process module 20. Thereafter, the inner space of the unload lock chamber 34 is replaced from a vacuum atmosphere to a normal pressure atmosphere, and is opened to the index module 10 while being blocked from the process module 20 .

The process module 20 may include a transfer unit 240 and a plurality of process chambers.

The transport unit 240 transports the substrate W between the load lock chamber 32 , the unload lock chamber 34 , and the plurality of process chambers 260 . The transfer unit 240 includes a transfer chamber 242 and a transfer robot 250 . The transfer chamber 242 may be provided in a hexagonal shape. Optionally, the transfer chamber 242 may be provided in a rectangular or pentagonal shape. Around the transfer chamber 242 , a load lock chamber 32 , an unload lock chamber 34 , and a plurality of process chambers 260 are positioned. A transport space 244 for transporting the substrate W is provided inside the transport chamber 242 .

The transport robot 250 transports the substrate W in the transport space 244 . The transfer robot 250 may be located in the center of the transfer chamber 240 . The transfer robot 250 may move in horizontal and vertical directions, and may have a plurality of hands 252 capable of moving forward, backward, or rotating on a horizontal plane. Each hand 252 can be driven independently, and the substrate W can be placed on the hand 252 in a horizontal state.

Below, the plasma processing apparatus 1000 provided in the process chamber 260 will be described. The plasma processing apparatus 1000 will be described as an apparatus for etching the substrate W. However, the plasma processing apparatus 1000 of this embodiment is not limited to an etching processing apparatus and can be applied in various ways.

2 is a cross-sectional view showing a process module according to an embodiment of the present invention.

Referring to FIG. 2 , the plasma processing apparatus 1000 includes a process chamber 1100, a substrate support unit 1200, a gas supply unit 1300, a plasma source 1400, an exhaust baffle 1500, and an image acquisition member 700. ) may be included.

Referring to FIG. 2 , the plasma processing apparatus 1000 processes a wafer W using plasma. As an example of the substrate, a semiconductor wafer (hereinafter simply referred to as "wafer W") is provided.

The plasma processing apparatus 1000 may include a process chamber 1100, a substrate support unit 1200, a plasma generating unit 1300, a gas supply unit 1400, a baffle unit 1500, and a controller (not shown). .

The process chamber 1100 provides a processing space 1101 in which a substrate processing process is performed. The processing space 1101 may be maintained at a process pressure lower than atmospheric pressure, and may be provided as a closed space. The process chamber 1100 may be made of a metal material. For example, the process chamber 1100 may be made of aluminum. A surface of the process chamber 1100 may be anodized. The process chamber 1100 may be electrically grounded. An exhaust hole 1102 may be formed on a bottom surface of the process chamber 1100 . The exhaust hole 1102 may be connected to the exhaust line 1151 . Reaction by-products generated during the process and gas remaining in the inner space of the chamber may be discharged to the outside through the exhaust line 1151 . The inside of the process chamber 1100 may be reduced to a predetermined pressure by the exhausting process.

According to an example, a liner 1130 may be provided inside the process chamber 1100 . The liner 1130 may have a cylindrical shape with open top and bottom surfaces. The liner 1130 may be provided to contact the inner surface of the chamber 1100 . The liner 1130 may protect the inner wall of the chamber 1100 from being damaged by an arc discharge. In addition, impurities generated during the substrate processing process may be prevented from being deposited on the inner wall of the chamber 1100 . The liner 1130 may be exposed to the processing space inside the process chamber 1100 to react with the first cleaning gas, and may include a material of yttria (Y2O3).

A window 1140 is provided above the process chamber 1100 . The window 1140 is provided in a plate shape. The window 1140 covers the open upper surface of the process chamber 1100 to seal the processing space 1101 . The window 1140 may include a dielectric substance.

A substrate support unit 1200 is provided inside the process chamber 1100 . In one embodiment, the substrate support unit 1200 may be spaced apart from the bottom surface of the chamber 1100 upward by a predetermined distance inside the chamber 1100 . The substrate support unit 1200 may support a wafer (W). The substrate support unit 1200 may include an electrostatic chuck (ESC) including an electrostatic electrode 1223 adsorbing the wafer W using electrostatic force. Alternatively, the substrate support unit 1200 may support the wafer W in various ways such as mechanical clamping. Hereinafter, the substrate support unit 1200 including the electrostatic chuck (ESC) will be described as an example.

The substrate support unit 1200 may include a susceptor, a base plate 1250 and a lift pin unit 1900 . The susceptor may be provided in a modular form including a dielectric plate 1220 , an electrode plate 1230 and an insulator plate 1270 .

The dielectric plate 1220 and the electrode plate 1230 may form an electrostatic chuck (ESC). The dielectric plate 1220 may support the wafer (W). A circumference of the dielectric plate 1220 may be surrounded by the focus ring 1240 . The dielectric plate 1220 may be positioned on top of the electrode plate 1230 . The dielectric plate 1220 may be provided with a disk-shaped dielectric substance. A wafer W may be placed on the upper surface of the dielectric plate 1220 . An upper surface of the dielectric plate 1220 may have a radius smaller than that of the wafer W. Therefore, an edge region of the wafer W may be located outside the dielectric plate 1220 . An edge of the wafer W may be placed on an upper surface of the focus ring 1240 .

The dielectric plate 1220 may include an electrostatic electrode 1223 , a heater 1225 , and a first supply channel 1221 therein. The first supply passage 1221 may be formed from the top surface of the dielectric plate 1220 through the bottom surface of the dielectric plate 1220 . A plurality of first supply passages 1221 are formed spaced apart from each other, and may be provided as passages through which a heat transfer medium is supplied to the lower surface of the wafer (W).

The electrostatic electrode 1223 may be electrically connected to the first power source 1223a. The first power supply 1223a may include DC power. A switch 1223b may be installed between the electrostatic electrode 1223 and the first power source 1223a. The electrostatic electrode 1223 may be electrically connected to or disconnected from the first power source 1223a by an ON/OFF operation of the switch 1223b. When the switch 1223b is turned on, DC current may be applied to the electrostatic electrode 1223 . An electrostatic force is applied between the electrostatic electrode 1223 and the wafer W by a current applied to the electrostatic electrode 1223 , and the wafer W may be adsorbed to the dielectric plate 1220 by the electrostatic force.

The heater 1225 may be positioned under the electrostatic electrode 1223 . The heater 1225 may be electrically connected to the second power source 1225a. The heater 1225 may generate heat by resisting a current applied from the second power source 1225a. The generated heat may be transferred to the wafer W through the dielectric plate 1220 . The wafer W may be maintained at a predetermined temperature by heat generated by the heater 1225 . The heater 1225 may include a spiral coil.

The electrode plate 1230 may be positioned below the dielectric plate 1220 . A bottom surface of the dielectric plate 1220 and an upper surface of the electrode plate 1230 may be bonded by an adhesive 1236 . The electrode plate 1230 may be made of aluminum. The upper surface of the electrode plate 1230 may be stepped so that the center region is higher than the edge region. A central region of the top surface of the electrode plate 1230 has an area corresponding to the bottom surface of the dielectric plate 1220 and may be adhered to the bottom surface of the dielectric plate 1220 . A first circulation passage 1231 , a second circulation passage 1232 , and a second supply passage 1233 may be formed inside the electrode plate 1230 .

The first circulation passage 1231 may be provided as a passage through which the heat transfer medium circulates. The first circulation passage 1231 may be formed in a spiral shape inside the electrode plate 1230 . Alternatively, in the first circulation passage 1231 , ring-shaped passages having different radii may have the same center. Each of the first circulation passages 1231 may communicate with each other. The first circulation channels 1231 may be formed at the same height.

The second circulation passage 1232 may serve as a passage through which the refrigerant circulates. The second circulation passage 1232 may be formed in a spiral shape inside the electrode plate 1230 . Alternatively, the second circulation passage 1232 may be arranged so that ring-shaped passages having different radii have the same center. Each of the second circulation passages 1232 may communicate with each other. The second circulation passage 1232 may have a larger cross-sectional area than the first circulation passage 1231 . The second circulation passages 1232 may be formed at the same height. The second circulation passage 1232 may be formed below the first circulation passage 1231 .

The second supply passage 1233 extends upward from the first circulation passage 1231 and may be provided as an upper surface of the electrode plate 1230 . The second supply passage 1243 is provided in a number corresponding to the first supply passage 1221 , and may connect the first circulation passage 1231 and the first supply passage 1221 .

The first circulation passage 1231 may be connected to the heat transfer medium storage unit 1231a through a heat transfer medium supply line 1231b. A heat transfer medium may be stored in the heat transfer medium storage unit 1231a. The heat transfer medium may contain an inert gas. According to an embodiment, the heat transfer medium may include helium (He) gas. The helium gas may be supplied to the first circulation passage 1231 through the supply line 1231b, and may be supplied to the bottom surface of the wafer W through the second supply passage 1233 and the first supply passage 1221 sequentially. . The helium gas may serve as a medium through which heat transferred from the plasma to the wafer W is transferred to the dielectric plate 1220 .

The second circulation passage 1232 may be connected to the refrigerant storage unit 1232a through a refrigerant supply line 1232c. Refrigerant may be stored in the refrigerant storage unit 1232a. A cooler 1232b may be provided in the refrigerant storage unit 1232a. The cooler 1232b may cool the refrigerant to a predetermined temperature. Alternatively, the cooler 1232b may be installed on the refrigerant supply line 1232c. The refrigerant supplied to the second circulation passage 1232 through the coolant supply line 1232c may circulate along the second circulation passage 1232 and cool the electrode plate 1230 . While the electrode plate 1230 is cooled, the dielectric plate 1220 and the wafer W may be cooled together to maintain the wafer W at a predetermined temperature. In one embodiment, the refrigerant may be supplied after being cooled to 0° C. or less (low temperature). In a preferred embodiment, the refrigerant may be cooled to -30°C or lower (cryogenic temperature). In an embodiment, the refrigerant cools the electrode plate 230 to a cryogenic temperature ranging from -30°C to -100°C, more preferably -30°C to -60°C.

The electrode plate 1230 may include a metal plate. According to an example, the entire electrode plate 1230 may be provided as a metal plate. The electrode plate 1230 may be electrically connected to the third power source 1235a. The third power source 1235a may be provided as a high frequency power source that generates high frequency power. The high frequency power source may include an RF power source. The electrode plate 1230 may receive high frequency power from the third power source 1235a. Due to this, the electrode plate 1230 may function as an electrode, that is, a lower electrode.

The focus ring 1240 may be disposed on an edge area of the dielectric plate 1220 . The focus ring 1240 has a ring shape and may be disposed along the circumference of the dielectric plate 1220 . An upper surface of the focus ring 1240 may be stepped so that the outer portion 1240a is higher than the inner portion 1240b. An inner portion 1240b of the top surface of the focus ring 1240 may be positioned at the same height as the top surface of the dielectric plate 1220 . The inner portion 1240b of the top surface of the focus ring 1240 may support an edge area of the wafer W positioned outside the dielectric plate 1220 . An outer portion 1240a of the focus ring 1240 may be provided to surround an edge area of the wafer W. The focus ring 1240 may control the electromagnetic field so that the plasma density is uniformly distributed over the entire area of the wafer W. As a result, plasma is uniformly formed over the entire area of the wafer (W) so that each area of the wafer (W) can be uniformly etched.

The base plate 1250 may be positioned at a lower end of the substrate support unit 1200 . The base plate 1250 may be spaced apart from the bottom surface of the chamber 1100 upwardly. A space 1255 may be formed inside the base plate 1250 . An air current may communicate with the outside of the space 1255 formed by the base plate 1250 . The outer radius of the base plate 1250 may be provided with the same length as the outer radius of the electrode plate 1230 .

An insulator plate 1270 may be positioned between the dielectric plate 1220 and the base plate 1250 . The insulator plate 1270 may cover an upper surface of the base plate 1250 . The insulator plate 1270 may have a cross-sectional area corresponding to that of the electrode plate 1230 . The insulator plate 1270 may include an insulator. The insulator plate 1270 may serve to increase an electrical distance between the electrode plate 1230 and the base plate 1250 .

3 is a view showing a pinhole.

As shown in FIG. 3 , a pin hole 1226 is formed in the dielectric plate 1220 . A pin hole 1226 is formed on the upper surface of the dielectric plate 1220 . Also, the pin hole 1236 may vertically pass through the dielectric plate 1220 . Although not shown, the pin hole 1226 is provided to communicate with the lower space 1225 of the base plate from the upper surface of the dielectric plate 1220 through the electrode plate 1230 and the insulator plate 1270 sequentially.

A plurality of pin holes 1226 may be formed. A plurality of pin holes 1226 may be disposed in a circumferential direction of the dielectric plate 1220 . For example, the three pin holes 1226 may be spaced apart from each other by 120 degrees in the circumferential direction of the dielectric plate 1220 . In addition, various numbers of pin holes 1226 may be formed, such as four pin holes 1226 spaced apart from each other at intervals of 90 degrees in the circumferential direction of the dielectric plate 1220 .

A lift pin unit 1900 may be positioned in the inner space 1255 of the base plate 1250 to move the wafer W from an external transport member to the dielectric plate 1220 . The lift pin unit 1900 may be spaced apart from the base plate 1250 by a predetermined interval. The base plate 1250 may be made of a metal material. Air may be provided to the inner space 1255 of the base plate 1250 . Since air has a lower dielectric constant than an insulator, it may serve to reduce an electromagnetic field inside the substrate support unit 1200 .

The base plate 1250 may have a connecting member 1253 . The connecting member 1253 may connect an outer surface of the base plate 1250 and an inner wall of the chamber 1100 . A plurality of connecting members 1253 may be provided on the outer surface of the base plate 1250 at regular intervals. The connection member 1253 may support the substrate support unit 1200 inside the chamber 1100 . Also, the connection member 1253 may be connected to the inner wall of the chamber 1100 so that the base plate 1250 is electrically grounded. A first power line 1223c connected to the first power supply 1223a, a second power line 1225c connected to the second power supply 1225a, and a third power line 1235c connected to the third power supply 1235a , The heat transfer medium supply line 1231b connected to the heat transfer medium storage unit 1231a, the refrigerant supply line 1232c connected to the refrigerant storage unit 1232a, etc. 1250) may be extended inwards.

The plasma generating unit 1300 may excite the process gas in the chamber 1100 to a plasma state. The plasma generating unit 1300 may use an inductively coupled plasma type plasma source. When an ICP type plasma source is used, an antenna 1330 provided on the top of the chamber 1100 and an electrode plate 1230 as a lower electrode provided on the chamber 1100 may be included. The antenna 1330 and the electrode plate 1230 may be vertically arranged parallel to each other with the processing space 1101 interposed therebetween. The antenna 330 as well as the electrode plate 1230 may receive an RF signal from the RF power supply 1310 to receive energy for generating plasma. An electric field is formed in a space between both electrodes, and a process gas supplied to the space may be excited into a plasma state. A substrate treatment process is performed using this plasma. An RF signal applied to the antenna 1330 and the electrode plate 1230 may be controlled by a controller (not shown). According to an embodiment of the present invention, a waveguide 1320 may be disposed on the antenna 1330. The waveguide 1320 transfers the RF signal provided from the RF power source 1310 to the antenna 1330. The waveguide 1320 may have a conductor retractable into the waveguide. The plasma generated by the plasma generating unit 1300 processes the wafer W cooled to an extremely low temperature (-30°C or lower). Plasma processing of the wafer W in a cryogenic environment is referred to as a cryogenic plasma process.

The gas supply unit 1400 may supply process gas into the chamber 1100 . The gas supply unit 1400 may include a gas supply nozzle 1410 , a gas supply line 1420 , and a gas storage unit 1430 .

The gas supply nozzle 1410 may be installed in the central portion of the window 1140, which is an upper surface of the chamber 1100. An injection hole may be formed on a lower surface of the gas supply nozzle 1410 . The injection hole may supply process gas into the chamber 1100 . The gas supply line 1420 may connect the gas supply nozzle 1410 and the gas storage unit 1430 . The gas supply line 1420 may supply process gas stored in the gas storage unit 1430 to the gas supply nozzle 1410 . A valve 1421 may be installed in the gas supply line 1420 . The valve 1421 opens and closes the gas supply line 1420 and can adjust the flow rate of process gas supplied through the gas supply line 1420 .

Process gases supplied by the gas supply unit 1400 include CF ₄ (methane), H ₂ (hydrogen), HBr (hydrogen bromide), NF ₃ (nitrogen trifluoride), CH ₂ F ₂ (difluoromethane), O ₂ (oxygen), F ₂ (fluorine), HF (hydrogen fluoride) may be any one or more or a combination thereof. On the other hand, the presented process gas may be selected differently as needed, despite an embodiment. A process gas according to an embodiment of the present invention is excited into a plasma state to etch a substrate.

The baffle unit 1500 may be positioned between the inner wall of the chamber 1100 and the substrate support unit 1200 . The baffle 1510 may be provided in a ring shape. A plurality of through holes 1511 may be formed in the baffle 1510 . The process gas provided in the process chamber 1100 may pass through the through holes 1511 of the baffle 1510 and be exhausted through the exhaust hole 1102 . The flow of process gas may be controlled according to the shape of the baffle 1510 and the through holes 1511 .

A controller (not shown) may control the entire operation of the substrate processing apparatus 1000 . The controller (not shown) may include a Central Processing Unit (CPU), Read Only Memory (ROM), and Random Access Memory (RAM). The CPU executes desired processing, such as an etching processing described later, according to various recipes stored in these storage areas. The recipe includes process time, process pressure, high frequency power or voltage, various gas flow rates, temperature in the chamber (temperature of the upper electrode, temperature of the side wall of the chamber, temperature of the electrostatic chuck, etc.), cooler 1232b, which is control information of the device for process conditions. temperature, etc. are entered. On the other hand, recipes indicating these programs and processing conditions may be stored in a hard disk or semiconductor memory. In addition, the recipe may be set in a predetermined position in the storage area while being accommodated in a storage medium readable by a portable computer such as a CD-ROM or DVD.

Meanwhile, the lift pin unit 900 loads the substrate W on the dielectric plate 1220 or unloads the substrate W from the dielectric plate 1220 through upward and downward movements.

4 is an enlarged view of the main part shown in FIG. 2, FIG. 5 is a cross-sectional view showing a coupled state of the lift pin and the pin holder in FIG. 4, and FIG. 6 is an exploded perspective view for explaining the lift pin and the pin holder of FIG.

2 to 6, the lift pin unit 1900 includes a lift pin 1910, a pin holder 1960, a support part 1920, a driving part 1930, a first elastic member 1970, and a second elastic member. (1980).

A plurality of lift pins 1910 are provided and accommodated in each of the pin holes 1226 . Here, the diameter of the lift pin 1910 is minutely smaller than the diameter of the pin hole 1226 . Specifically, the diameter of the lift pin 1910 is the minimum diameter at which the lift pin 1910 does not contact the inner wall of the pinhole 1226 when the lift pin 1910 and the pinhole 1226 are arranged to have the same central axis. can be provided with

Meanwhile, the lift pin 1910 has a joint ball 1912 at its lower end. The lift pins 1910 move vertically along the pin holes 1226 and load/unload the substrate W. For example, the lift pin 1910 rises to support the substrate transferred to the susceptor by a transfer arm (not shown), and then descends to load the substrate into the susceptor. As another example, the lift pins 1910 unload the substrate by raising and supporting the substrate on the susceptor, and then descend again when the substrate is transferred by the transfer arm.

The support part 1920 or the support member is located in the inner space 1255 of the base plate 1250 and supports the lift pins 1910 . The support part 1920 may be connected to the driving part 1930 or the lifting member.

The driving unit 1930 may be located outside the chamber 1100 . A hydraulic or pneumatic cylinder may be used as the driving unit 1930, but is not limited thereto. Although one driving unit 1930 is shown in the drawing, a plurality of driving units may be included to elevate each of the lift pins 1910.

The support plate 1920 and the lift pins 1910 may be interconnected to a pin holder 1960 .

The pin holder 1960 may include an upper holder 1960a as an upper body and a lower holder 1960b as a lower body. The upper holder 1960a and the lower holder 1960b may be coupled to each other using a bolt fastening method. For example, a screw part 1966 is provided on the bottom surface of the upper holder 1960a, and a screw hole 1967 into which the screw part 1966 is fastened is provided on the upper surface of the lower body 1960b.

The pin holder 1960 includes a ball socket 1962. A joint ball 1912 is inserted into the ball socket 1962, and the lift pin 1910 can pivot in a shape surrounding the joint ball 1912. Provided.

The first elastic deformable member 1970 is elastically deformed when the joint ball 1912 pivots to provide a return force to return the lift pin 1910 to its original position toward the vertical central axis C. For example, the first elastically deformable member 1970 may be provided in the shape of a silicon material having elastic restoring force. The first elastic deformable member 1970 has one end inserted into the first insertion groove 1914 of the joint ball 1912 and the other end inserted into the second insertion groove 1964 of the ball socket 1962. The first insertion groove 1914 and the second insertion groove 1964 are provided on a straight line with the vertical central axis (C).

The pin holder 1960 may be provided to the support 1920 to move in a horizontal direction. To enable movement in the horizontal direction, the pin holder 1960 is not directly connected to the support 1920, but is connected by the second elastically deformable member 1980.

The second elastic deformable member 1980 is elastically deformed when the pin holder 1960 moves horizontally, and provides a return force to return the pin holder 1960 to its original position before horizontal movement. The second elastically deformable member 1980 may be provided in the shape of a silicon material having elastic restoring force. The second elastically deformable member 1980 has one end inserted into the third insertion groove 1968 formed on the bottom surface of the pin holder 1960 and the other end inserted into the fourth insertion groove 1922 formed on the upper surface of the support part 1920. do. The third insertion groove 1968 and the fourth insertion groove 1922 are provided on the same vertical line.

7A and 7B are views showing that the lift pin is returned to its original position along the vertical central axis (C) by the first and second elastic deformable members.

As shown in FIGS. 7A and 7B , shrinkage occurs when the susceptor of the substrate support unit 1200 is brought to a cryogenic state by the refrigerant. At this time, since the lift pin 1910 can pivot the joint ball 1912 and horizontally move the pin holder 1960, stress between the lift pin 1910 and the pin holder 1960 can be minimized to prevent breakage. . At this time, the first elastic deformable member 1970 is elastically deformed by the pivot rotation of the joint ball 1912, and the second elastic deformable member 1980 is also elastically deformed by the horizontal movement of the pin holder 1960. become a state

As shown in FIG. 7B, when the thermal deformation of the susceptor is removed, the lift pin 1910 moves to the vertical central axis by the return force (elastic restoring force) of the first elastic deformation member 1970 and the second elastic deformation member 1980. will be in place

The substrate support unit according to the present invention can be applied not only to the Inductively Coupled Plasma (ICP) device shown in the embodiment, but also to other plasma processing devices. Other plasma processing devices include capacitively coupled plasma (CCP: Capacitively Coupled Plasma), plasma processing device using a radial line slot antenna, Helicon Wave Excitation Plasma (HWP: Helicon Wave Plasma) device, electron cyclotron resonance 　 plasma ( ECR: Electron Cyclotron Resonance Plasma) devices and the like.

In addition, the substrate processed by the substrate processing apparatus according to the present invention is not limited to a wafer, and may be, for example, a large substrate for a flat panel display, a substrate for an EL element or a solar cell.

Although the etching process has been described as an example, it may also be applied to a substrate processing apparatus that performs a deposition process.

Since not all of the components or steps are essential in the embodiments described in this specification, the present invention may selectively include some of the components or steps. Also, the construction steps do not necessarily have to be performed in the order described, so it is possible for later described steps to be performed prior to earlier described steps.

Furthermore, the above-described embodiments are not necessarily performed independently, and may be used individually or in combination with each other.

1000: plasma processing device 1100: process chamber
1200: substrate support unit 1300: plasma generating unit
1400: gas supply unit 1500: baffle unit
1900: lift pin unit

Claims (20)

In the substrate support unit for supporting the substrate,
a susceptor supporting a substrate and having pinholes formed in a vertical direction;
A lift pin unit for loading and unloading a substrate on the susceptor;
The lift pin unit
a lift pin provided to move up and down along the pinhole;
a support that is moved up and down by a driving unit;
including a pin holder connecting the support portion and the lift pin;
The lift pin
connected to the pin holder so as to be pivotally rotatable about a vertical central axis of the pinhole;
The pin holder
A substrate support unit connected to the support to be movable in a horizontal direction. According to claim 1,
The lift pin
Including a joint ball,
The pin holder
A substrate support unit comprising a ball socket into which the joint ball is inserted and capable of pivoting the lift pin in a shape surrounding the joint ball. According to claim 2,
The lift pin unit
The substrate support unit further includes a first elastically deformable member configured to elastically deform when the joint ball pivots and provide a return force to return the lift pin to its original position toward the vertical central axis. According to claim 3,
The first elastic deformable member
A substrate support unit comprising a pin-shaped first connection pin having an elastic restoring force, one end inserted into the first insertion groove of the joint ball and the other end inserted into the second insertion groove of the ball socket. According to claim 4,
The first insertion groove and the second insertion groove are provided on a straight line with the vertical central axis. According to claim 2,
The lift pin unit
and a second elastically deformable member configured to elastically deform when the pin holder moves horizontally and provide a return force to bring the pin holder back to its original position before the horizontal movement. According to claim 6,
The second elastic deformable member
A substrate support unit including a pin-shaped second connection pin having an elastic restoring force, one end inserted into the third insertion groove formed on the bottom surface of the pin holder, and the other end inserted into the fourth insertion groove formed on the upper surface of the support part. . According to claim 7,
The third insertion groove and the fourth insertion groove are provided on the same vertical line substrate support unit. In the lift pin unit for loading and unloading substrates:
a lift pin inserted into the pinhole;
a support that is moved up and down by a driving unit;
including a pin holder connecting the support portion and the lift pin;
The lift pin
connected to the pin holder so as to be pivotally rotatable about a vertical central axis of the pinhole;
The lift pin
Including a joint ball,
The pin holder
A lift pin unit including a ball socket into which the joint ball is inserted and capable of pivoting the lift pin in a shape surrounding the joint ball. According to claim 9,
The lift pin unit
The lift pin unit further includes a first elastically deformable member configured to elastically deform when the joint ball pivots and provide a return force to return the lift pin to its original position toward the vertical central axis. According to claim 10,
The first elastic deformable member
A lift pin unit comprising a pin-shaped first connecting pin having an elastic restoring force and having one end inserted into the first insertion groove of the joint ball and the other end inserted into the second insertion groove of the ball socket. According to claim 11,
The first insertion groove and the second insertion groove are provided on a straight line with the vertical central axis. According to claim 9,
The pin holder
Doedoe connected to the support to enable horizontal movement;
The lift pin unit
The lift pin unit further includes a second elastically deformable member that is elastically deformed when the pin holder is horizontally moved and provides a return force to return the pin holder to its original position before horizontal movement. According to claim 13,
The second elastic deformable member
A lift pin unit including a pin-shaped second connection pin having an elastic restoring force, one end inserted into the third insertion groove formed on the bottom surface of the pin holder, and the other end inserted into the fourth insertion groove formed on the upper surface of the support part. . 15. The method of claim 14,
The lift pin unit wherein the third insertion groove and the fourth insertion groove are provided on the same vertical line. According to claim 9,
The pin holder
An upper holder connected to the lift pin and a lower holder connected to the support,
The lift pin unit wherein the upper holder and the lower holder are coupled to each other by a bolt method. a process chamber forming a processing space;
a gas supply unit supplying a process gas into the process chamber;
a plasma generating unit generating plasma from the process gas introduced into the process chamber;
a substrate support unit provided in the processing space and supporting a substrate;
The substrate support unit,
a dielectric plate embedded with an electrostatic electrode adsorbing the substrate by electrostatic force;
an electrode plate provided under the dielectric plate and having a passage through which a refrigerant flows;
an annular focus ring provided around the dielectric plate;
an insulator plate provided under the electrode plate and made of an insulator;
a base plate provided under the insulator plate and grounded;
Including a lift pin unit provided in the inner space of the base plate;
The lift pin unit
lift pins inserted into pinholes penetrating the dielectric plate, the electrode plate, and the insulator plate;
a support that is moved up and down by a driving unit;
including a pin holder connecting the support portion and the lift pin;
The lift pin
connected to the pin holder so as to be pivotally rotatable about a vertical central axis of the pinhole;
The pin holder
A substrate processing apparatus connected to the support to be movable in a horizontal direction. 18. The method of claim 17,
The lift pin
Including a joint ball,
The pin holder
A ball socket into which the joint ball is inserted and a ball socket capable of pivoting the lift pin in a shape surrounding the joint ball,
The lift pin unit
The substrate processing apparatus further includes a first elastic deformation member for providing a return force to elastically deform the joint ball when pivoting and return the lift pin to its original position toward the vertical central axis. According to claim 18,
The lift pin unit
Further comprising a second elastic deformable member that is elastically deformed when the pin holder is horizontally moved to provide a return force to return the pin holder to its original position before horizontal movement;
The second elastic deformable member
A substrate processing apparatus comprising a pin-shaped second connection pin having an elastic restoring force, one end inserted into the third insertion groove formed on the bottom surface of the pin holder, and the other end inserted into the fourth insertion groove formed on the upper surface of the support part. . 18. The method of claim 17,
The process chamber is a substrate processing apparatus for processing a substrate using cryogenic plasma.

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