JP2020115519A - Mounting table and substrate processing device - Google Patents

Abstract

To prevent particles from being generated from a through hole of a lifter pin.SOLUTION: A mounting table includes a base, a mounting portion arranged on the base, an adhesive layer arranged between the base and the mounting portion, a lifter pin that raises and lowers an object to be processed mounted on the mounting portion and/or an edge ring arranged around the object to be processed, an elevating mechanism that raises and lowers the lifter pin, and a seal member that is arranged on the upper part of the adhesive layer around a through hole of the lifter pin and maintains contact between the inner peripheral surface and the lifter pin according to the raising and lowering of the lifter pin.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to a mounting table and a substrate processing apparatus.

When a wafer is transferred, the lifter pins that pass through the electrostatic chuck can be moved up and down to place the wafer on the mounting surface of the electrostatic chuck or lift it from the mounting surface of the electrostatic chuck. Be seen.

For example, Patent Document 1 includes a plurality of lift pins that penetrate the electrostatic chuck, and a space between the lift pins and the electrostatic chuck is separated from a space below the electrostatic chuck by a bellows and a sealing ring, and a bellows is used. This allows the lift pins to move up and down.

JP, 2005-216391, A

The present disclosure provides a mounting table and a substrate processing apparatus capable of preventing particles from being generated from a through hole of a lifter pin.

According to one aspect of the present disclosure, a base, a mounting portion arranged on the base, an adhesive layer arranged between the base and the mounting portion, and The object to be processed placed on the workpiece and/or a lifter pin for elevating and lowering an edge ring arranged around the object, an elevating mechanism for elevating and lowering the lifter pin, and an adhesive layer around the through hole of the lifter pin. And a seal member disposed on the upper part of the seal member for maintaining contact between the inner peripheral surface of the lifter pin and the lifter pin as the lifter pin moves up and down.

According to the one aspect, it is possible to prevent particles from being generated from the through hole of the lifter pin.

1 is a schematic sectional view showing an example of a substrate processing apparatus according to an embodiment. The figure which shows an example of the mounting base which concerns on one Embodiment. The figure which shows an example of the effect of the mounting base which concerns on one Embodiment.

Hereinafter, modes for carrying out the present disclosure will be described with reference to the drawings. In each drawing, the same components may be denoted by the same reference numerals and redundant description may be omitted.

[Substrate processing equipment]
FIG. 1 is a schematic cross-sectional view showing the configuration of the substrate processing apparatus according to this embodiment. The substrate processing apparatus 100 has a processing container 1 which is airtight and electrically set to a ground potential. The processing container 1 has a cylindrical shape and is made of, for example, aluminum. In the processing container 1, a mounting table 2 on which the wafer W is mounted is provided. The mounting table 2 has a base 2 a and an electrostatic chuck 6. The base 2a is made of a conductive metal such as aluminum.

The support base 4 supports the mounting base 2. The support base 4 is arranged at the bottom of the processing container 1 via a support member 3 made of, for example, quartz. An edge ring 5 made of, for example, silicon is provided around the wafer W. The edge ring 5 is also called a focus ring. Around the base 2a, the edge ring 5, and the support 4, an inner wall member 3a of, for example, a quartz cylindrical shape is provided.

The electrode 6a in the electrostatic chuck 6 is sandwiched between the insulators 6b and connected to the power supply 12. When a voltage is applied to the electrode 6 a from the power source 12, the wafer W is electrostatically attracted to the electrostatic chuck 6 by the Coulomb force.

The mounting table 2 has a coolant channel 2d inside. A coolant, for example, cooling water supplied from a chiller unit (not shown) circulates through the coolant inlet pipe 2b, the coolant flow passage 2d, and the coolant outlet pipe 2c. Further, a heat transfer gas such as helium gas is supplied to the back surface of the wafer W from a gas supply pipe 30 penetrating the mounting table 2. With this configuration, the wafer W is controlled at a predetermined temperature.

The mounting table 2 is provided with a plurality of, for example, three pin through holes 200 (only one is shown in FIG. 1). The lifter pin 61 in the pin through hole 200 is connected to the drive mechanism 62 and moves up and down by the drive of the drive mechanism 62. The structure around the pin through hole 200 and the lifting mechanism for lifting the lifter pin 61 will be described later.

The first RF power supply 10a is connected to the base via the first matching box 11a, and the second RF power supply 10b is connected to the base via the second matching box 11b. The first RF power supply 10a applies high frequency power for plasma generation having a predetermined frequency to the base 2a. The second RF power source 10b applies high-frequency power for ion attraction having a frequency lower than the frequency of high-frequency power for plasma generation to the base 2a. A shower head 16 facing the mounting table 2 is provided above the mounting table 2. The shower head 16 and the mounting table 2 function as a pair of electrodes (upper electrode and lower electrode).

The shower head 16 has a main body portion 16a and an upper top plate 16b forming an electrode plate. The shower head 16 is supported by the insulating member 95 and closes the upper opening of the processing container 1. The main body portion 16a is made of a conductive material, for example, aluminum whose surface is anodized, and the upper top plate 16b is detachably supported on the lower portion thereof.

A gas inlet 16g for introducing the processing gas into the gas diffusion chamber 16c is formed in the main body portion 16a. A gas supply pipe 15a is connected to the gas inlet 16g. A processing gas supply source (gas supply unit) 15 is connected to the gas supply pipe 15a. The gas supply pipe 15a is provided with a mass flow controller (MFC) 15b and an opening/closing valve V2 in order from the upstream side. The processing gas is supplied from the processing gas supply source 15 to the gas diffusion chamber 16c in the main body 16a via the gas supply pipe 15a.

A large number of gas passage holes 16d are formed in the lower portion of the gas diffusion chamber 16c, and communicate with gas introduction holes 16e penetrating the upper top plate 16b. The processing gas is supplied into the processing container 1 in a shower shape through the gas diffusion chamber 16c, the gas flow hole 16d and the gas introduction hole 16e.

A variable DC power supply 72 is electrically connected to the shower head 16 via a low pass filter (LPF) 71. The variable DC power source 72 is turned on/off by a switch 73. The DC voltage from the variable DC power source 72 and on/off of the switch 73 are controlled by the control unit 90. When high-frequency power is applied to the mounting table 2 from the first RF power source 10a and the second RF power source 10b and the processing gas is turned into plasma, the switch 73 is turned on by the controller 90 as necessary, and the shower is performed. A predetermined DC voltage is applied to the head 16.

A cylindrical ground conductor 1a is provided so as to extend from the side wall of the processing container 1 to a position higher than the height of the shower head 16. The cylindrical ground conductor 1a has a ceiling wall on its upper part.

An exhaust port 81 is formed at the bottom of the processing container 1, and an exhaust device 83 is connected to the exhaust port 81 via an exhaust pipe 82. The exhaust device 83 has a vacuum pump, and the inside of the processing container 1 is depressurized to a predetermined vacuum degree by operating the vacuum pump. A wafer loading/unloading port 84 is provided on the sidewall of the processing container 1, and a gate valve 85 for opening/closing the loading/unloading port 84 is provided at the loading/unloading port 84.

A deposition shield 86 is provided inside the side portion of the processing container 1 along the inner wall surface. The deposit shield 86 prevents the etching by-product (depot) from adhering to the processing container 1. A conductive member (GND block) 89 having a controllable potential with respect to the ground is provided at a position of the deposition shield 86 substantially at the same height as the wafer W, thereby preventing abnormal discharge. A deposit shield 87 extending along the inner wall member 3a is provided at the lower end of the deposit shield 86. The deposit shields 86 and 87 are detachable.

The operation of the substrate processing apparatus 100 having the above configuration is controlled by the control unit 90. The control unit 90 is provided with a process controller 91 that controls each unit of the substrate processing apparatus 100, a user interface 92, and a storage unit 93.

The user interface 92 includes a keyboard through which a process manager inputs commands to manage the substrate processing apparatus 100, a display that visualizes and displays the operating status of the substrate processing apparatus 100, and the like.

The storage unit 93 stores a recipe in which a control program (software) for causing the process controller 91 to execute various types of processing executed by the substrate processing apparatus 100, processing condition data, and the like are stored. Then, if necessary, by calling an arbitrary recipe from the storage unit 93 by the instruction from the user interface 92 and causing the process controller 91 to execute the recipe, the substrate processing apparatus 100 is controlled under the control of the process controller 91. Is processed. For the recipes such as the control program and the processing condition data, those stored in a computer-readable computer storage medium or the like are used, or transmitted from other devices at any time through, for example, a dedicated line. It is also possible to use it online. Examples of the storage medium include a hard disk, a CD, a flexible disk, a semiconductor memory and the like.
[Structure of mounting table]
Next, the configuration of the mounting table 2 will be described with reference to FIGS. 2 and 3. 2 and 3 are schematic cross-sectional views showing the mounting table 2 in the substrate processing apparatus 100 of FIG. 2 and 3B show a case where the lifter pin 61 is raised to support the wafer W, and FIG. 3A is a view where the lifter pin 61 is lowered to place the wafer W on the electrostatic chuck 6. The case where it is placed on the surface is shown.

Through holes (hereinafter, also referred to as “pin through holes 200”) through which the lifter pins 61 can be inserted from below the base 2a to above the electrostatic chuck 6 are formed in the base 2a and the electrostatic chuck 6. Has been done. The electrostatic chuck 6 has a disk shape, and has a mounting surface 21 on which the wafer W is mounted, and a back surface 22 facing the mounting surface 21. The mounting surface 21 has a circular shape, and contacts the back surface of the wafer W to support the wafer W. The adhesive layer 7 is disposed between the base 2 a and the electrostatic chuck 6, and adheres the base 2 a to the back surface 22 of the electrostatic chuck 6.

An end portion (gas hole) of the gas supply pipe 30 is formed on the mounting surface 21. The gas supply pipe 30 supplies helium gas for heat transfer. The end of the gas supply pipe 30 is formed by a through hole 30a formed in the electrostatic chuck 6 and a through hole 30b formed in the base 2a. The through hole 30 a is provided so as to penetrate from the back surface 22 of the electrostatic chuck 6 to the mounting surface 21, and the inner wall of the through hole 30 a is formed by the electrostatic chuck 6. On the other hand, the through hole 30b is provided so as to penetrate from the back surface of the base 2a to the joint surface with the electrostatic chuck 6, and the inner wall of the through hole 30b is formed by the base 2a. The hole diameter of the through hole 30b is larger than the hole diameter of the through hole 30a. The electrostatic chuck 6 and the base are arranged so that the through hole 30a and the through hole 30b communicate with each other. In the gas supply pipe 30, a gas sleeve 204 made of a conductor such as aluminum and a gas spacer 202 made of an insulator such as ceramics are arranged.

The pin through hole 200 is an example of a through hole of the lifter pin 61. The pin through hole 200 is formed by a through hole 200 a formed in the electrostatic chuck 6 and a through hole 200 b formed in the base, and accommodates the lifter pin 61. The through hole 200a has a hole diameter matched with the outer diameter of the lifter pin 61, that is, a hole diameter slightly larger than the outer diameter of the lifter pin 61 (for example, about 0.1 to 0.5 mm larger), and the through hole 200a is internally provided. 61 is moved up and down. The hole diameter of the through hole 200b is larger than the hole diameter of the through hole 200a, for example. A pin sleeve 203 and a pin spacer 201 are arranged between the inner wall of the through hole 200b and the lifter pin 61, and the pin sleeve 203 and the pin spacer 201 form a part of the pin through hole 200. It

At least a part of the lifter pin 61 is made of sapphire. The lifter pin 61 has a cylindrical shape and has an outer diameter of, for example, about several mm. The pin upper end portion 61a of the lifter pin 61 has a spherical surface.

The lifter pin 61 moves up and down in the pin through hole 200 by the drive mechanism 62, and moves freely up and down from the mounting surface 21 of the mounting table 2. The drive mechanism 62 adjusts the height of the stop position of the lifter pin 61 so that the pin upper end portion 61a of the lifter pin 61 is located immediately below the back surface of the wafer W when the lifter pin 61 is housed.

With such a configuration, as shown in FIG. 3A, when the lifter pin 61 is lowered, the lifter pin 61 is accommodated in the pin through hole 200, and the wafer W is mounted on the mounting surface 21. Placed. On the other hand, as shown in FIG. 3B, when the lifter pins 61 are raised, the lifter pins 61 project from the mounting surface 21 of the mounting table 2, and the wafer W is supported on the mounting table 2. It will be in the state of doing. Thus, the lifter pins 61 carry the wafer W in the vertical direction.

Returning to FIG. 2, in the pin through hole 200 of the lifter pin 61, a bellows 310 is provided between the base 2 a and the support base 4 and below the support base 4. Power from the drive mechanism 62 is transmitted to the elevating part 310a at the bottom of the bellows 310, and the drive mechanism 62 moves the elevating part 310a up and down, so that the bellows 310 moves as shown in FIGS. Stretch and move the lifter pin up and down. The upper portion 310b of the bellows 310 is fitted and fixed between the base 2a and the support 4. The drive mechanism 62 has an arbitrary type of drive source such as a motor and a gas pressure type lift mechanism.

The bellows 310 separates the atmospheric space U below the bellows 310 in the pin through hole 200 of the lifter pin 61 from the vacuum space V above the bellows 310 in the pin through hole 200.

By using the bellows 310 in this way, the lifter pin 61 can be moved up and down without affecting the vacuum environment in the processing container 1. At that time, a signal is sent from the process controller 91 to the drive mechanism 62, and the drive mechanism 62 is driven according to the signal to control the positioning of the bellows 310.

As a result, the bellows 310 is gradually moved upward, and accordingly, the lifter pins 61 are exposed to high stress that may damage the wafer W while the wafer W is electrostatically attracted to the electrostatic chuck 6. Is contacted with the lower surface of the wafer W so that no voltage is applied. Further, the bellows 310 is gradually moved upward, and the lifter pins 61 are raised accordingly, and the wafer W is lifted from the electrostatic chuck 6.

By these operations, particles P are generated in the pin through holes 200 of the lifter pins 61 that lift up the wafer W. As shown in FIG. 3B, the particles P move above the pin through holes 200 as the lifter pin 61 rises. In the present embodiment, in order to prevent particles that have moved upward from jumping out from the pin through hole 200, the seal member 300 is provided around the pin through hole 200.

The seal member 300 has a base portion 300a and a protrusion portion 300b having a convex shape in the inner circumferential direction. The seal member 300 is attached to the ceramic plate that constitutes the electrostatic chuck 6. By disposing the seal member 300 on the electrostatic chuck 6 above the adhesive layer 7, it is possible to prevent the adhesive layer 7 from being exposed to plasma and consumed.

The seal member 300 is preferably made of a material having plasma resistance. For example, the seal member 300 may be formed of a fluorine-based material such as vinylidene fluoride (FKM), polytetrafluoroethylene (PTFE), or tetrafluoroethylene-purple orovinyl ether (FFKM).

The seal member 300 is flexible and easy so that a gap does not occur between the lifter pin 61 and the protrusion 300b according to the vertical movement of the lifter pin 61 when the central axis of the lifter pin 61 is displaced. It is composed of varying shapes, sizes and materials.

When an O-ring is used instead of the seal member 300, when the central axis of the lifter pin 61 is displaced, the lifter pin 61 is in contact with one side of the O-ring, but the lifter pin 61 is not in contact with the other side. May be That is, as a result of the gap being formed between the lifter pin 61 and the O-ring, it may not be possible to prevent particles that have moved upward as the lifter pin 61 rises from jumping out from the pin through hole 200.

On the other hand, the seal member 300 maintains contact between the lifter pin 61 and the protrusion 300b and uses a soft material or a protrusion 300b to prevent a gap from being formed between the lifter pin 61 and the protrusion 300b. The shape can be easily changed by reducing the thickness of the.

With this configuration, the seal member 300 maintains contact between the lifter pin 61 and the convex shape that is the inner peripheral surface of the seal member 300 according to the vertical movement of the lifter pin 61. Accordingly, it is possible to prevent particles from being generated from the pin through hole 200 to the outside by the operation of the bellows 310 and the lifter pin 61. Further, by maintaining the contact between the lifter pin 61 and the seal member 300 according to the vertical movement of the lifter pin 61, plasma radicals enter the inside of the pin through hole 200, and the adhesive layer 7 and the like are deteriorated. It is possible to prevent abnormal discharge from occurring due to the invasion of plasma.

In addition, the convex shape of the protrusion 300b may be one, or may be two or more steps. Further, the thickness of the convex shape of the protrusion 300b is not limited, and may be flat or may have irregularities. The seal member 300 may have a shape without the protrusion 300b as long as the contact between the lifter pin 61 and the seal member 300 can be maintained according to the vertical movement of the lifter pin 61.

As described above, according to the mounting table 2 of the present embodiment, it is possible to prevent particles from being generated from the pin through hole 200 of the lifter pin 61. Further, the adhesive layer 7 that adheres the electrostatic chuck 6 and the base 2a can be protected from plasma.

The bellows 310 is an example of a stretchable member that surrounds the lifter pin 61 and moves the lifter pin 61 up and down. Further, the electrostatic chuck 6 is an example of a mounting portion arranged on the base 2a, and the mounting table 2 may not have the electrostatic chuck 6. When the electrostatic chuck 6 is not included, the mounting unit is a disk-shaped member on which the wafer W is mounted, and does not have to have a function of electrostatically attracting the wafer W.

In the present embodiment, the configuration in which particles are prevented from being generated from the pin through hole 200 due to the vertical movement of the lifter pin 61 that penetrates the pin through hole 200 provided in the mounting table 2 has been described.

However, the present invention is not limited to this, and a pin provided below the edge ring 5 on the outer peripheral side of the mounting table 2 through which a lifter pin (not shown) for raising and lowering the edge ring 5 arranged around the wafer W penetrates. You may apply to the structure which prevents that a particle generate|occur|produces from the through hole for use. Also in this case, the seal member is arranged above the adhesive layer 7 around the pin through hole below the edge ring 5. The seal member maintains contact between the inner peripheral surface (for example, the protrusion of the seal member) and the lifter pin according to the vertical movement of the lifter pin. As a result, it is possible to prevent particles from being generated from the pin through hole provided below the edge ring 5. Further, the adhesive layer 7 exposed in the pin through hole provided below the edge ring 5 can be protected from plasma.

It should be considered that the mounting table and the substrate processing apparatus according to the embodiment disclosed this time are examples in all respects and not restrictive. The above-described embodiments can be modified and improved in various forms without departing from the scope and spirit of the appended claims. The matters described in the above plurality of embodiments can have other configurations as long as they do not contradict each other, and can be combined in a range that does not contradict.

In this specification, the wafer W has been described as an example of the substrate. However, the substrate is not limited to this, and may be various substrates used for FPD (Flat Panel Display), a printed circuit board, or the like.

In addition, the substrate processing apparatus 100 includes any type of substrate processing such as Capacitively Coupled Plasma (CCP), Inductively Coupled Plasma (ICP), Radial Line Slot Antenna (RLSA), Electron Cyclotron Resonance Plasma (ECR), and Helicon Wave Plasma (HWP). It is also applicable to devices. The substrate processing apparatus 100 may be an apparatus that uses plasma or an apparatus that does not use plasma.

1 Processing Container 2 Placement Table 2a Base 5 Edge Ring 6 Electrostatic Chuck 7 Adhesive Layer 16 Shower Head 61 Lifter Pin 62 Drive Mechanism 100 Substrate Processing Device 200 Through Hole for Pin 300 Seal Member 300a Base 300b Protrusion 310 Bellows

Claims (10)

A base,
A mounting portion arranged on the base,
An adhesive layer arranged between the base and the placing part,
A lifter pin for moving up and down an object to be processed placed on the placing part and/or an edge ring arranged around the object to be processed,
An elevating mechanism for elevating the lifter pin,
A seal member arranged on the upper part of the adhesive layer around the through hole of the lifter pin, and maintaining contact between the inner peripheral surface and the lifter pin according to the lifting and lowering of the lifter pin,
Mounting table having. The lifting mechanism raises and lowers the lifter pin by an elastic member surrounding the lifter pin,
The mounting table according to claim 1. The above-mentioned mounting portion is an electrostatic chuck,
The mounting table according to claim 1 or 2. The seal member is provided on a sidewall of a through hole of the lifter pin provided on the electrostatic chuck,
The mounting table according to claim 3. The seal member has a convex shape in the inner circumferential direction,
The mounting table according to any one of claims 1 to 4. The convex shape is one or more,
The mounting table according to claim 5. The seal member is formed of a material having plasma resistance,
The mounting table according to any one of claims 1 to 6. The space below the seal member and above the seal member in the through hole of the lifter pin is a vacuum space,
The mounting table according to any one of claims 1 to 7. Below the elastic member of the through hole of the lifter pin is an atmospheric space, and above the elastic member is a vacuum space,
The mounting table according to any one of claims 1 to 8. Having a mounting table on which the object to be processed is mounted,
The above mentioned table is
A base,
A mounting portion arranged on the base,
An adhesive layer arranged between the base and the placing part,
A lifter pin for moving up and down an object to be processed placed on the placing part and/or an edge ring arranged around the object to be processed,
An elevating mechanism for elevating the lifter pin,
A seal member arranged on the upper part of the adhesive layer around the through hole of the lifter pin, and maintaining contact between the inner peripheral surface and the lifter pin according to the lifting and lowering of the lifter pin,
A substrate processing apparatus having:

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