JPH11265681A - Ion implanting substrate holding device and ion implanting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ion implanting substrate holding device and ion implanting device capable of surely holding an ion implanting substrate such as a wafer with a large diameter and sufficiently cooling the ion implanting substrate heated in the implantation of ions. SOLUTION: In an ion implanting substrate holding device for an ion implanting device, its holding mechanism has a holding table 1 for holding an ion implanting substrate (wafer wf), a mechanical clamp having a clamp claw 3, an electrostatic chuck 2, and a gas cooling mechanism for supplying a cooling gas between the holding table 1 and the ion implanting substrate to cool the ion implanting substrate. Further, this mechanism is provided with an interlocking means for interlocking the operation and stop of the electrostatic chuck 2 to the opening and closing operation stop of the clamp claw 3, and a gas supplying and stopping mechanism for performing the start/stop of supply of the cooling gas between the holding table 1 and the ion implanting substrate simultaneously with the detachment and attachment of the ion implanting substrate to the holding table 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single-wafer ion implantation apparatus for implanting ions into an ion implantation substrate such as a large-diameter semiconductor wafer. It relates to an injection device.

[0002]

2. Description of the Related Art Conventionally, there have been many batch-type ion implantation apparatuses for implanting ions into a semiconductor wafer. In the batch-type ion implantation apparatus, for example, a plurality of wafers are placed along the circumferential direction on the inner peripheral surface of a conical plate having a conical inner peripheral surface. The wafer is fixed using a clamp jig or the like. As the conical plate is rotated about its central axis, the wafer revolves around the central axis of the conical plate. The orbiting wafer crosses the ion beam irradiation area at a certain position on the orbit, and ions are implanted at that time.

The wafer placed on the inner peripheral surface of the conical plate is
It is pressed against the inner peripheral surface by centrifugal force. The wafer mounting surface is formed of rubber or the like having good thermal conductivity, and the entire surface of the wafer is cooled while being in close contact with the rubber. Each wafer is heated during the period during which the ion beam is irradiated during one revolution, and is cooled during the other periods. In this way, the temperature during the ion implantation is maintained at 90 to 100 ° C. or lower.

On the other hand, in a wafer holding method of a single wafer type ion implantation apparatus, a peripheral edge of a wafer is forcibly pressed and held mechanically by a clamp on a platen having substantially the same diameter one by one. . For example, by circulating the wafer vertically with respect to the horizontally scanned beam, the entire surface of the wafer can be irradiated with the beam.

[0005]

In the above batch type ion implantation apparatus, the wafer is brought into close contact with rubber,
There is the problem of particles adhering to the wafer. On the other hand, in a single-wafer ion implantation apparatus, unlike a batch system, a strong wafer pressing force due to the revolving centrifugal force cannot be obtained, and the entire wafer surface cannot be sufficiently adhered to a heat transfer medium such as rubber. There is a problem that the wafer cannot be cooled sufficiently. In particular, in a single-wafer type in which the ion beam is radiated intensively one by one, the amount of heat input by the irradiation of the ion beam also increases, and the cooling power for cooling the wafer becomes a problem.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has been made in view of the above circumstances, and is capable of securely holding an ion-implanted substrate such as a large-diameter wafer and sufficiently cooling the ion-implanted substrate heated during ion implantation. It is to provide a substrate holding device and an ion implantation device.

[0007]

According to a first aspect of the present invention, there is provided an ion implantation substrate having a holding mechanism for holding an ion implantation substrate, wherein the ion implantation substrate held by the holding mechanism is placed in a vacuum chamber. An ion implantation substrate holding device of an ion implantation device for irradiating an ion beam and implanting ions,
The holding mechanism includes a holding table for holding the ion-implanted substrate, a mechanical clamp for mounting the ion-implanted substrate on the holding table using mechanical force, and mounting the ion-implanted substrate on the holding table using electrostatic force. And an interlocking means for interlocking the operation / stop of the electrostatic chuck with the operation / stop of the mechanical clamping mechanism.

According to a second aspect of the present invention, there is provided a holding mechanism for holding the ion-implanted substrate, and the ion-implanted substrate held by the holding mechanism is irradiated with an ion beam in a vacuum chamber to implant ions. An ion implantation substrate holding device of an ion implantation apparatus, wherein a holding mechanism holds a ion implantation substrate, and cools the ion implantation substrate by supplying a cooling gas between the holding stage and the ion implantation substrate. It is characterized by having a gas cooling mechanism.

According to a third aspect of the present invention, there is provided a holding mechanism for holding an ion-implanted substrate, and the ion-implanted substrate held by the holding mechanism is irradiated with an ion beam in a vacuum chamber to implant ions. An ion-implanted substrate holding device of an ion-implanting device, wherein a holding mechanism holds a ion-implanted substrate, a mechanical clamp that attaches the ion-implanted substrate to the holder using mechanical force, and an electrostatic force. An electrostatic chuck for mounting the ion-implanted substrate on the holding table using
A gas cooling mechanism for supplying a cooling gas between the holding table and the ion-implanted substrate to cool the ion-implanted substrate,
An interlocking means for interlocking the operation and stop of the electrostatic chuck with the operation and stop of the mechanical clamp mechanism is provided, and the desorption of the ion-implanted substrate from the holder and the supply of the cooling gas between the holder and the ion-implanted substrate. A gas supply stop mechanism for simultaneously starting / stopping is provided.

[0010] The invention described in claim 4 is the first invention.
4. An ion-implanted substrate holding device comprising any one of the ion-implanted substrate holding devices of the ion-implanted substrate holding devices described in 3 to 3, which is held by the ion-implanted substrate holding device by the ion-implanted substrate moving device. The ion implanted substrate is moved to an ion irradiation area through which an ion beam passes, and ions are implanted into the ion implanted substrate.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing a configuration example of the ion-implanted substrate holding device of the present invention, FIG. 2 is a plan view thereof, and FIG. 3 is a plan view showing a configuration example of the ion implantation device. FIG.
2, reference numeral 1 denotes a wafer holder, and an electrostatic chuck 2 is provided on the wafer holder 1, and the wafer wf is sucked by the electrostatic force (Coulomb force) of the electrostatic chuck 2. The wafer is held by suction on the wafer holding surface of the holding table 1. The wafer holding surface of the wafer holding table 1 is provided with a gas blowing hole 1a for blowing gas, and supplies gas at a pressure of 1 to 5 torr to a gap between the wafer holding surface and the wafer wf to form a gas film. It is supposed to.

More specifically, as shown in FIG. 4, a radial groove 2a communicating with the gas blowing hole 1a and a concentric groove 2b are formed on the wafer suction surface 2c of the electrostatic chuck 2. The gas that has passed through the blowing hole 1a flows through the grooves 2a and 2b. Also, the wafer holding table 1
As shown in FIG. 5, a cooling water passage 1b is formed on the entire surface of the cooling water passage.
L / min.

The gas film g (the wafer suction surface 2c of the electrostatic chuck 2) filled in the gap between the wafer holding surface of the wafer holding table 1 (the wafer suction surface of the electrostatic chuck 2) and the wafer wf.
The gas layer filled with the grooves 2a and 2b) functions as a heat transfer medium, and is heated by ion implantation.
It is designed to cool down. If this gas is not supplied to the gap between the wafer holding surface of the wafer holding table 1 and the wafer wf, the gap will be in a vacuum state (because the ion implantation chamber is in a vacuum state) and the heat radiation from the wafer wf will be poor. However, by flowing the gas and forming the gas film g in this way, heat radiation from the wafer wf is improved. Further, even if a gas is blown onto the surface of the wafer wf by the force of the electrostatic chuck 2, the wafer is held by suction on the wafer holding table 1 and sufficient pressing is performed on the entire surface of the wafer.

The wafer holder 1 has a disk shape, and a plurality of (four in the figure) clamp claws 3 are rotatably supported by a support shaft 12 at the peripheral edge thereof. The tip of 3 is in contact with the side surface of the peripheral portion of the wafer wf, and the other end is connected to the clamp lever 4. Further, the clamp lever 4 is constantly urged in a direction away from the wafer holding table 1 by the elastic force of a leaf spring 5 between the clamp lever 4 and the wafer holding table 1. That is, the plurality of clamp claws 3 are constantly urged by the elastic force of the leaf spring 5 in the direction of pressing the peripheral portion of the wafer wf (the direction in which the clamp claws 3 are closed).

Reference numeral 7 denotes a wafer lift mechanism having a clamp opening / closing function for opening / closing the clamp claw 3 and a lift function for lifting the wafer wf. The wafer lift mechanism 7 is supported by an arm 14 that rotates about an elevation drive shaft 13. .
The wafer lift mechanism 7 is stored so as to be in contact with the inner surface of the processing chamber (ion beam irradiation chamber) 36, and is lifted by rotating the arm 14 about the vertical drive shaft 13. Note that, in FIG.
Is a magnetic fluid seal, and the magnetic fluid seal 15 keeps the inside and outside of the side wall of the processing container 36 airtight and is isolated from each other.

A clamp claw 3 is provided on the periphery of the wafer holding table 1.
The pin 8 is provided adjacent to each of the pin levers.
6 is connected to a piston 19 of an air cylinder 18 disposed inside the wafer lift mechanism 7 via a lifting member 17. The sliding portion of the elevating member 17 is surrounded by the bellows 21. A compressed air supply hole 14a is provided inside the arm 14, and the compressed air 20 sent through the compressed air supply hole 14a is supplied to the air cylinder 18 through the flexible tube 11.

The arm 14 is rotated about the lifting drive shaft 13 to lift the wafer lift mechanism 7 and position it below the wafer holder 1 as shown in FIG. By raising the wafer lift mechanism 7 via the arm 14 in this state, the projection 7a comes into contact with the clamp lever 4 and applies a force to the clamp lever 4 from below. As a result, the clamp levers 4 move upward, the respective clamp claws 3 rotate about the support shaft 12, and the clamp claws 3 operate in the opening direction.

With the clamp claw 3 opened as described above, the wafer wf is loaded into the load lock chamber 31 or 32.
The wafer wf is taken out from the wafer by the transfer arm 33 or 34, and in a state where the wafer wf is moved to the mounting position, the tips of the four pins 8 are projected on the wafer holding surface of the wafer holding table 1 on the four pins 8. And lift the wafer wf.

The transfer arm 33 or 34 retreats and the pin 8
Is lowered, the wafer wf is placed on the wafer holding table 1. When the wafer lift mechanism 7 is receded downward as it is, the clamp lever 4 is pressed by the elastic force of the leaf spring 5, and the clamp claw 3 closes to press and hold the peripheral portion of the wafer wf from the side.

A single pole type electrostatic chuck is used. When the clamp claw 3 comes into contact with the side surface of the wafer wf, the wafer wf
At the same time, the bias voltage of 500 V to 1500 V is applied to the electrostatic chuck 2 at the same time as being grounded through the clamp claw 3, and the chucking of the wafer wf is started by the electrostatic force. That is, the holding of the wafer wf by the clamp claw 3 and the suction of the electrostatic chuck 2 are performed in conjunction with each other.

On the other hand, the gas blowing holes 1 of the wafer holding table 1
The bellows type gas supply valve 9 is provided in the immediate vicinity of a, and as shown in FIG.
A ring 22 is mounted. The gas supply valve 9 is connected to the clamp lever 4. Wafer lift mechanism 7
By pushing up the clamp lever 4 by the projection 7a, the O-ring 22 at the tip of the gas supply valve 9 is pressed against the wall around the gas outlet 1a, and the gas outlet 1a is pressed.
To stop gas from blowing out. On the other hand, the clamp lever 4 descends to move the O-ring 2 at the tip of the gas supply valve 9.
When the nozzle 2 is separated from the wall around the gas outlet 1a, gas is blown out from the gas outlet 1a.

That is, the holding of the wafer wf by the clamp claw 3 and the electrostatic chuck 2, the supply of gas to the gap between the wafer holding surface of the wafer holding table 1 and the wafer wf,
The opening of the wafer wf by the electrostatic chuck 2 and the stop of the gas supply to the gap are interlocked. The gas is supplied to a gas valve chamber 1d in which a gas supply valve 9 is accommodated through a gas supply hole 1c provided on a side portion of the wafer holding table 1, and from the gas valve chamber 1d to a gas blowout hole 1a. The wafer is supplied to a gap between the wafer holding surface of the wafer holding table 1 and the wafer wf.
The sliding portion of the gas supply valve 9 is sealed with a bellows 23.

As shown in FIG. 3, two wafer moving devices 37 each having the above-described ion-implanted substrate holding device are disposed in the processing vessel (ion beam irradiation chamber) 36. The wafer wf held on the wafer holding surface of the wafer holding table 1 of the wafer moving device 37 is moved (scanned) in front of the ion current detector 38 and in a direction perpendicular to the ion beam 39, so that the wafer wf is moved. Implant ions.

The wafer wf is heated by the heat input by the ion implantation. As described above, the cooling water passage 1b is formed in the wafer holding base 1, and the cooling water is supplied to the cooling water passage 1b. Since the gas film g is formed by the gas filled in the gap between the wafer holding surface 1 and the wafer wf, the gas film g acts as a heat transfer medium to cool the heated wafer wf. Also, the electrostatic chuck 2
Accordingly, a sufficient pressing force can be obtained on the entire surface of the wafer wf.

FIG. 7 is a perspective view showing a schematic configuration example of the wafer moving device 37. The wafer moving device 37 includes a horizontal moving mechanism 40, an arm driving mechanism 50, and a telescopic arm 60. The horizontal moving mechanism 40 includes a horizontal rotation shaft 41 and a motor 42. A timing belt 43 is suspended between the horizontal rotation shaft 41 and the drive shaft of the motor 42. When the motor 42 is driven, the horizontal rotation shaft 41 rotates.

An arm drive mechanism 50 is attached to the upper end of the horizontal rotation shaft 41. By driving the motor 42, the arm driving mechanism 50 can be rotated around the horizontal rotation shaft 41. The arm driving mechanism 50 includes an arm driving shaft 51 having a biaxial structure, a motor 54, and a motor 55. The arm drive shaft 51 includes a center shaft 52
And an outer shaft 53, which is held horizontally. The timing belt 5 is provided between the center shaft 52 and the drive shaft of the motor 54.
6 is suspended, and the center shaft 52 is rotated by the motor 54. A timing belt 57 is suspended between the outer shaft 53 and the drive shaft of the motor 55, and the outer shaft 53 is rotated by the motor 55.

The telescopic arm 60 includes a first sub-arm 61 attached to the outer shaft 53 and a second sub-arm 62 rotatably attached to the end thereof. At the tip of the second sub arm 62, the wafer holding table 1 is shown in FIG.
As shown in FIG.

When the central shaft 52 and the outer shaft 53 are simultaneously rotated, the telescopic arm 60 is rotated without changing the relative positions of the first sub-arm 61, the second sub-arm 62, and the wafer holder 1. When the center shaft 52 is fixed and only the outer shaft 53 is rotated, the first sub-arm 61 and the second sub-arm 62
Changes its narrow angle, and the telescopic arm 60 expands and contracts.
At this time, even if the wafer holding table 1 changes the angle between the wafer holding surface and the second sub arm 62 in accordance with the expansion and contraction of the telescopic arm 60, the direction of the wafer holding surface does not change even if the telescopic arm 60 is expanded and contracted.

Therefore, by fixing the center shaft 52 and rotating the outer shaft 53, the wafer holder 1 can be translated. By rotating the center shaft 52 and the outer shaft 53 simultaneously, the direction of the wafer holding surface of the wafer holding table 1 can be changed. The wafer wf held by the wafer holding table 1 at the tip of the second sub arm 62 of the wafer moving device 37 is moved in a direction perpendicular to the ion beam 39 as described above, thereby implanting ions into the wafer wf.

As shown in FIG. 3, two wafer moving devices 37 are provided in the processing vessel 36, and ions are implanted into the wafer wf by the two wafer moving devices 37. The wafer wf is translated in a direction perpendicular to the ion beam 39.

In the above embodiment, the wafer holding device of the ion implantation device for implanting ions into the wafer wf has been described as an example, but the ion implantation substrate held by the ion implantation substrate holding device of the present invention is limited to the wafer. However, it can be naturally used widely as a substrate holding device for an ion-implanted substrate for implanting ions.

[0032]

As described above, according to the invention described in each claim, the following effects can be obtained. According to the first aspect of the present invention, since the holding mechanism mechanically clamps the holding table, the electrostatic chuck, and the ion implantation substrate, the ion implantation substrate is securely held by the mechanical clamp and the electrostatic chuck. Can be performed.

According to the second aspect of the present invention, the holding mechanism has a gas cooling mechanism for cooling the ion-implanted substrate by supplying a cooling gas between the holding table and the ion-implanted substrate.
The gas film that fills the space between the holding table and the ion-implanted substrate acts as a heat conduction medium, and can effectively cool the ion-implanted substrate heated by the heat input during ion implantation.

According to the third aspect of the present invention, the holding mechanism includes a holding table, an electrostatic chuck, a mechanical clamp, and a cooling gas supplied between the holding table and the ion-implanted substrate, thereby holding the ion-implanted substrate. Since a gas cooling mechanism for cooling and a gas supply stop mechanism for simultaneously detaching the ion-implanted substrate from the holding table and starting / stopping the supply of the cooling gas are provided, the desorption of the ion-implanted substrate and the start of cooling of the ion-implanted substrate are started. Stop can be linked.

According to the invention described in claim 4, according to claim 1
It is possible to provide an ion implantation apparatus having the functions of the ion implantation substrate holding device according to any one of the first to third aspects.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration example of an ion-implanted substrate holding device of the present invention.

FIG. 2 is a plan view illustrating a configuration example of an ion-implanted substrate holding device of the present invention.

FIG. 3 is a plan view showing a configuration example of the ion implantation apparatus of the present invention.

FIG. 4 is a plan view showing a configuration example of a suction surface of the electrostatic chuck.

FIG. 5 is a diagram showing a shape of a cooling water passage formed in a wafer holding table.

FIG. 6 is a view showing a configuration example of a gas supply valve portion of a cooling mechanism of the ion implantation substrate holding device of the present invention.

FIG. 7 is a perspective view showing a schematic configuration example of a wafer moving device of the ion implantation apparatus of the present invention.

FIG. 8 is a view showing a relationship between an arm of a wafer moving device of the ion implantation apparatus of the present invention and an ion implantation substrate holding device.

[Explanation of symbols]

 Reference Signs List 1 wafer holding table 2 electrostatic chuck 3 clamp claw 4 clamp lever 5 leaf spring 7 wafer lift mechanism 8 pin 9 gas supply valve 11 flexible tube 12 support shaft 13 elevating drive shaft 14 arm 15 magnetic fluid seal 16 pin lever 17 elevating member 18 air cylinder Reference Signs List 19 piston 20 compressed air 31 load lock chamber 32 load lock chamber 33 transfer arm 34 transfer arm 37 wafer moving device 38 ion current detector 39 ion beam

Claims (4)

[Claims] An ion-implanted substrate holding device for an ion-implanted device, comprising a holding mechanism for holding an ion-implanted substrate, irradiating the ion-implanted substrate held by the holding mechanism with an ion beam in a vacuum chamber and implanting ions. Wherein the holding mechanism holds the ion-implanted substrate, a mechanical clamp that attaches the ion-implanted substrate to the holder using mechanical force, and the ion-implanted substrate that uses electrostatic force. And an electrostatic chuck attached to the holding table,
An ion-implanted substrate holding device for an ion-implantation device, comprising interlocking means for interlocking the operation and stop of the electrostatic chuck with the operation and stop of the mechanical clamp mechanism. 2. An ion implantation substrate holding apparatus for an ion implantation apparatus, comprising: a holding mechanism for holding an ion implantation substrate; and irradiating the ion implantation substrate held by the holding mechanism with an ion beam in a vacuum chamber to implant ions. Wherein the holding mechanism includes a holding table that holds the ion-implanted substrate, and a gas cooling mechanism that cools the ion-implanted substrate by supplying a cooling gas between the holding table and the ion-implanted substrate. An ion-implanted substrate holding device for an ion-implantation device. 3. An ion-implanted substrate holding device for an ion-implanted device, comprising a holding mechanism for holding an ion-implanted substrate, irradiating the ion-implanted substrate held by the holding mechanism with an ion beam in a vacuum chamber and implanting ions. Wherein the holding mechanism holds the ion-implanted substrate, a mechanical clamp that attaches the ion-implanted substrate to the holder using mechanical force, and the ion-implanted substrate that uses electrostatic force. An electrostatic chuck mounted on the holding table, and a gas cooling mechanism for supplying a cooling gas between the holding table and the ion-implanted substrate to cool the ion-implanted substrate. Along with providing interlocking means for interlocking the operation and stop of the electrostatic chuck with the operation and stop,
A gas supply stop mechanism for simultaneously detaching the ion-implanted substrate from the holder and starting / stopping the supply of the cooling gas between the holder and the ion-implanted substrate; Ion-implanted substrate holding device. 4. An ion-implanted substrate moving device comprising one of the ion-implanted substrate holding devices according to claim 1, wherein the ion-implanted substrate moving device comprises: An ion implantation apparatus comprising: moving an ion implantation substrate held by the ion implantation substrate holding device to an ion irradiation region through which an ion beam passes; and implanting ions into the ion implantation substrate.