JP2015043272A - Ion implantation equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology that raises an operation rate of ion implantation equipment.SOLUTION: A platen unit 200 comprises a plurality of platens 21 and 22 that have holding surfaces 21a and 22a for holding a substrate S, a support member 24, and a rotary mechanism part. The support member 24 supports the plurality of platens 21 and 22 in such a manner that normal lines of the holding surfaces 21a and 22a are parallel with a first plane. The rotary mechanism part makes any one of the plurality of platens 21 and 22 arranged in a position to apply an ion beam 1D, by a rotating shaft 25a elongated in a first axial direction perpendicular to the first plane.

Description

  The present invention relates to an ion implantation apparatus used for manufacturing a semiconductor device.

  Various types of ion implantation apparatuses are known in which ions from an ion source are accelerated to a desired energy and implanted into a solid surface such as a semiconductor substrate. For example, in Patent Document 1 below, a desired ion species is extracted from an ion source that generates ions, accelerated or decelerated to a desired energy, and an ion beam is scanned at least in a one-dimensional plane on a substrate implantation surface by a scanner. In addition, an ion implantation apparatus that performs parallel implantation using a collimator is disclosed.

  On the other hand, in recent years, not only Si substrates but also SiC substrates have begun to be used as semiconductor substrates. SiC is expected to be mainly used for next-generation power devices because it has lower power loss, higher breakdown voltage, and higher heat conduction characteristics than Si. For example, Patent Document 2 below discloses a method for manufacturing a power MOS transistor using a SiC substrate.

JP 2006-351312 A JP 2011-138852 A

  In the production of a power device using a SiC substrate, it is necessary to heat and implant the substrate at a high temperature of 250 ° C. or higher in order to avoid damage (crystal defects) that occurs in the ion implantation process. Accordingly, since it takes time to raise the temperature (preheating) of the substrate before implantation, the waiting time for processing becomes long and the throughput is deteriorated. Further, when ion implantation is performed at different temperatures, the standby time for changing the temperature of the platen holding the substrate has caused a deterioration in throughput.

  In view of the circumstances as described above, an object of the present invention is to provide an ion implantation apparatus capable of realizing improvement in apparatus operation rate.

In order to achieve the above object, an ion implantation apparatus according to an embodiment of the present invention includes a beam irradiation source, a plurality of platens, a support member, and a rotation mechanism unit.
The beam irradiation source is configured to emit an ion beam.
Each of the plurality of platens has a holding surface configured to hold a substrate.
The support member supports the plurality of platens so that a normal line of each holding surface is parallel to the first plane.
The rotation mechanism unit has a rotation axis connected to the support member and extending in a first axial direction perpendicular to the first plane, and any one of the plurality of platens is moved to the irradiation position of the ion beam. It can be arranged.

1 is a schematic configuration diagram showing an ion implantation apparatus according to a first embodiment of the present invention. It is a partially broken perspective view which shows roughly the structure of the platen unit in the said ion implantation apparatus. It is a side view of the principal part of the said platen unit. It is a side view of the principal part of the platen unit in the ion implantation apparatus concerning the 2nd Embodiment of this invention.

An ion implantation apparatus according to an embodiment of the present invention includes a beam irradiation source, a plurality of platens, a support member, and a rotation mechanism unit.
The beam irradiation source is configured to be able to emit an ion beam.
Each of the plurality of platens has a holding surface configured to hold the substrate.
The support member supports the plurality of platens so that a normal line of each holding surface is parallel to the first plane.
The rotation mechanism section has a rotation axis connected to the support member and extending in a first axial direction perpendicular to the first plane, and any one of the plurality of platens is moved to the ion beam irradiation position. It can be arranged.

  The ion implantation apparatus includes a plurality of platens, and is configured such that an arbitrary platen can be disposed at the irradiation position of the ion beam by the rotation mechanism unit. As a result, a plurality of substrates can be held at one time. For example, while ions are implanted into a substrate held on one platen, the temperature of the unprocessed substrate held on the other platen is raised. It becomes possible to make it. Therefore, according to the above ion implantation apparatus, the waiting time required for the pre-processing or post-processing of the substrate can be shortened, so that the throughput of the ion implantation process performed at a high temperature is increased, and the apparatus operating rate can be improved. .

The plurality of platens may be arranged at rotationally symmetric positions with respect to the rotation axis.
Thereby, each platen can be arranged at the irradiation position of the ion beam only by rotating the rotating shaft by the rotating mechanism. Therefore, for example, it is not necessary to change the irradiation position for each platen by the beam irradiation source, and ions can be implanted into the substrate on each platen at a certain irradiation position.

The ion implantation apparatus may further include a linear movement mechanism that can reciprocate the support member in a second axial direction orthogonal to the first axial direction.
Thus, ions incident on the substrate can be scanned along the second axial direction. Therefore, for example, when the ion beam emitted from the beam irradiation source is scanned in the first axial direction, or is a ribbon-like ion beam parallel to a second plane orthogonal to the first plane, The entire surface of the substrate can be irradiated with an ion beam.

Each of the plurality of platens may further include a temperature adjustment mechanism capable of adjusting the temperature of the holding surface.
The temperature adjustment mechanism may be a heater unit that heats the holding surface or a cooling unit that cools the holding surface. Moreover, it is not restricted to when each platen has the same temperature control mechanism, One platen may have a heater unit and the other platen may each have a cooling unit. Accordingly, for example, it is possible to perform a process of performing ion implantation at a high temperature and a process of performing ion implantation at a normal temperature with a single apparatus.

  The number of platens is not particularly limited, and typically includes 2 to 4 platens. In the case of two platens, each platen is spaced 180 ° around the axis of rotation. In the case of three platens, each platen is spaced 120 ° around the axis of rotation. Similarly, if the number of platens is four, each platen is disposed 90 ° apart around the axis of rotation.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<First Embodiment>
FIG. 1 is a schematic configuration diagram showing an ion implantation apparatus according to a first embodiment of the present invention. Hereinafter, the overall configuration of the ion implantation apparatus 100 will be described.

[Ion implantation equipment]
The ion implantation apparatus 100 includes an ion source 10, a mass separator 20, a mass separation slit 30, an acceleration tube 40, a quadrupole lens 50, a scanner 60, a collimator 70, and an end station 80. Have As will be described later, the end station 80 includes a platen unit 200 that holds a substrate S to be subjected to an ion implantation process.

  The ion source 10 is an apparatus that strips electrons from atoms and molecules to generate ions 1A. The mass separator 20 generates a magnetic field and / or an electric field by utilizing the property that charged particles such as ions and electrons are deflected in a magnetic field or an electric field, so that the ion species 1B to be injected into the substrate S can be obtained. It is a device for specifying.

  The acceleration tube 40 is a device that accelerates or decelerates the desired ion species 1B that has passed through the mass separation slit 30. The accelerating tube 40 is typically configured to be axially symmetric and has a plurality of electrode pairs arranged at equal intervals. A high voltage equal to these electrode pairs is applied to the ions 1B by the action of an electrostatic field. Accelerate or decelerate to the desired implantation energy. The quadrupole lens 50 is for adjusting the beam shape of ions that have passed through the acceleration tube 40.

  The scanner 60 generates a uniform external electric field in a direction orthogonal to the traveling direction of beam-like ions (hereinafter also referred to as ion beam) 1C that has passed through the quadrupole lens 50, and the polarity and intensity of the electric field. Is changed to control the deflection angle of the ions 1C. In the present embodiment, the scanner 60 scans the ion beam 1 </ b> C in a predetermined direction toward the input stage of the collimator 70.

  The collimating device 70 is incident on the surface of the substrate S of the substrate S at a right angle or substantially at a right angle while suppressing the spread of the beam due to the difference in the path of each ion constituting the ion beam 1C. An apparatus for forming an ion beam 1D. The collimator 70 utilizes the property that ions 1C, which are charged particles, are deflected in a magnetic field, and typically includes an electromagnet. The collimating device 70 functions as a beam scanning unit that scans the ion beam 1D in the X-axis direction (first axis direction) as described later.

  The end station 80 includes an ion source 1D emitted from a beam irradiation source including the ion source 10, the mass separator 20, the mass separation slit 30, the acceleration tube 40, the quadrupole lens 50, the scanner 60, and the collimator 70. A substrate S to be irradiated is accommodated. Typically, a resist mask or an inorganic mask is formed on the surface of the substrate S, and predetermined ions are implanted at a predetermined depth and a predetermined dose into a substrate region exposed from the opening of the mask. . Examples of the substrate S include a Si substrate, a SiC substrate, and a glass substrate.

  Further, although not shown, for example, a shutter device that blocks the ion beam, a Faraday cup that measures the beam current, and the like may be provided between the collimator 70 and the end station 80.

  Each device constituting the beam irradiation source and the inside of the end station 80 are maintained in a predetermined vacuum atmosphere by a vacuum exhaust device, although not shown. The end station 80 includes a platen unit 200 that holds the substrate S. Hereinafter, details of the platen unit 200 will be described.

[Platen unit]
FIG. 2 is a partially broken perspective view schematically showing the configuration of the platen unit 200. FIG. 3 is a side view of the main part of the platen unit 200. In each figure, an X axis, a Y axis, and a Z axis indicate three axial directions orthogonal to each other.

  The platen unit 200 includes a plurality of platens 21 and 22, a support member 24, and a rotation mechanism unit 25.

  The platen unit 200 according to this embodiment includes a first platen 21 and a second platen 22 as a plurality of platens. The first and second platens 21 and 22 are configured in the same manner, and have circular holding surfaces 21a and 22a configured to hold one substrate S, respectively.

  Although the holding surfaces 21a and 22a are formed to be larger than the substrate S, the holding surfaces 21a and 22a are not limited to this and may be formed to have a size equal to or smaller than that of the substrate S. The holding mechanism for the substrate S is not particularly limited, and an electrostatic chuck mechanism is employed in the present embodiment, but a mechanical chuck mechanism may be employed in addition to this.

  The first and second platens 21 and 22 have temperature adjustment mechanisms 21b and 22b that can adjust the temperatures of the holding surfaces 21a and 22a, respectively. The temperature adjustment mechanisms 21b and 22b may be heater units that heat the holding surfaces 21a and 21b, or may be cooling units that cool the holding surfaces 21a and 22a. In the present embodiment, each of the temperature adjustment mechanisms 21b and 22b is composed of a heater unit.

  The heating temperature of the holding surfaces 21a and 22a is not particularly limited, and can be set as appropriate according to the type of substrate, ion implantation conditions, and the like. In the present embodiment, a SiC substrate is used as the substrate S, and the heating temperature is adjusted in a range of 250 ° C. to 800 ° C., for example.

  The support member 24 is disposed between the first platen 21 and the second platen 22 and integrally supports the first and second platens 21 and 22. The first and second platens 21 and 22 are supported by the support member 24 so that the holding surfaces 21a and 22a are parallel to the YZ plane (first plane).

  A rotation shaft 25a of the rotation mechanism unit 25 is connected to the support member 24, and the support member 24 is configured to be rotatable around the rotation shaft 25a. The first and second platens 21 and 22 are arranged at rotationally symmetric positions with respect to the rotation shaft 25a.

  In the present embodiment, the first and second platens 21 and 22 are arranged with an interval of 180 ° around the rotation shaft 25a. Each holding surface 21a, 22a is directed to the opposite side, and each normal line of the holding surfaces 21a, 22a is arranged on the same straight line parallel to the Y-axis direction.

  The rotation mechanism unit 25 has a rotation shaft 25 a connected to the support member 24. The rotation shaft 25a extends in the X-axis direction (first axial direction), and supports the first and second platens 21 and 22 via the support member 24 so as to be rotatable around the X-axis. The rotation mechanism unit 25 is configured to be able to place any one of the first and second platens 21 and 22 at the irradiation position of the ion beam 1D.

  Here, as shown in FIG. 1, if the ion beam 1D is linearly emitted in the Y-axis direction from the collimator 70, the ion beam 1D is irradiated at the holding surface 21a or the holding surface. It is set at a position where it is incident at a predetermined angle on 22a. In the present embodiment, the irradiation position of the ion beam 1D is set to a position where the ion beam 1D is perpendicularly incident on the holding surface 21a or the holding surface 22a.

  The rotation mechanism unit 25 is typically composed of an electromagnetic motor, and is preferably composed of a pulse motor capable of controlling the rotation angle of the rotation shaft 25a with high accuracy. The rotation mechanism unit 25 is supported by a base 27 installed inside the end station 80, and is driven and controlled by a controller (not shown) that controls the functions of the ion implantation apparatus 100 as a whole.

  The platen unit 200 further includes a linear movement mechanism unit 26. The linear movement mechanism unit 26 is configured to be able to reciprocate the support member 24 and the first and second platens 21 and 22 in the Z-axis direction.

  In the present embodiment, the linear movement mechanism unit 26 is disposed on the base 27 and includes a feed screw 26 a that supports the rotation mechanism unit 25. The rotation mechanism unit 25 has a nut portion 25b into which the feed screw 26a is screwed. The feed screw 26a is a shaft-like member extending in the Z-axis direction and is configured to be rotatable around the Z-axis. Thereby, the linear movement mechanism part 26 reciprocates the rotation mechanism part 25, the support member 24, and the first and second platens 21 and 22 in the Z-axis direction by controlling the rotation direction and the rotation amount of the feed screw 26a. It becomes possible to make it.

  Although not shown, the base 27 has an appropriate restricting structure for restricting the rotation of the rotating mechanism 25 around the feed screw 26a, whereby the rotating shaft 25a is in a posture parallel to the X-axis direction. Thus, the platens 21 and 22 can be moved in the Z-axis direction.

  The linear movement mechanism unit 26 is typically composed of an electromagnetic motor, and is preferably composed of a pulse motor capable of controlling the rotation angle of the feed screw 26a with high accuracy. The linear movement mechanism unit 26 is driven and controlled by the controller.

  The end station 80 has a substrate transfer port for loading / unloading a substrate, and an unprocessed substrate is transferred to the platen unit 200 via a substrate transfer mechanism (not shown), or a processed substrate is It is unloaded from the platen unit 200.

[Operation of ion implanter]
Next, a typical operation of the ion implantation apparatus 100 of the present embodiment configured as described above will be described. Here, a SiC substrate is used as the substrate S, and the process of ion-implanting the substrate S at a high temperature will be described as an example.

  The substrate S is held on the first and second platens 21 and 22 of the platen unit 200, respectively. Each substrate S is heated to a predetermined temperature by the temperature adjusting mechanisms 21b and 22b on the holding surfaces 21a and 22a. Then, the first platen 21 is disposed at the beam irradiation position facing the beam emitting port of the collimator 70 by the rotation mechanism unit 25 and the linear movement mechanism unit 26.

  Next, an ion beam is generated in the beam irradiation source. The ions 1A extracted from the ion source 10 are sorted into desired ions 1B by the mass separator 20 and the mass separation slit 30, and then accelerated or decelerated to a predetermined energy according to the implantation depth in the acceleration tube 40. The The ion beam 1 </ b> C adjusted to a desired energy in this way is introduced into the collimator 70 via the quadrupole lens 50 and the scanner 60.

  The collimator 70 forms an ion beam 1D which is parallel to the Y-axis direction and scanned in the X-axis direction, and is held by the platen unit 200 (first platen 21) in the end station 80. The light is emitted toward the surface of the substrate S.

  As shown in FIG. 2, the ion beam 1 </ b> D is applied to the surface of the substrate S held on the holding surface 21 a of the first platen 21. The ion beam 1D has an optical axis parallel to the Y-axis direction and is scanned in the X-axis direction. Therefore, the ion beam 1D is emitted from the collimator 70 as a ribbon-like ion beam parallel to the XY plane (second plane), and is irradiated on the surface of the substrate S.

  The first platen 21 (and the second platen 22) is reciprocated in the Z-axis direction by the linear movement mechanism unit 26. Thereby, the ion beam 1D is irradiated to the entire ion implantation region on the substrate S. The moving speed, the number of reciprocations, etc. are not particularly limited, and are appropriately set according to the size of the substrate S, the dose amount, and the like. In the present embodiment, since the ion beam 1D is configured to be perpendicularly incident on the substrate, ions can be implanted into the entire ion implantation region on the substrate S with a uniform dose.

  When ion implantation of a predetermined dose amount to the substrate S is completed, the beam irradiation process is interrupted, and the first and second platens 21 and 22 are rotated by 180 ° around the rotation axis 25a by the rotation mechanism unit 25, and the second The substrate S held on the platen 22 is placed at the beam irradiation position. Then, the ion beam irradiation process is resumed, and a predetermined dose of ion implantation is performed on the entire surface of the substrate S held on the holding surface 22a as described above.

  In the present embodiment, since a plurality of substrates S can be held at one time, heating of the substrate S on the second platen 22 is performed while the ion implantation process is being performed on the substrate S on the first platen 21. Processing can be performed. Thereby, after the ion implantation of the substrate S on the first platen 21 is completed, the ion implantation process for the substrate S on the second platen 22 can be started immediately.

  In addition, since the first platen 21 and the second platen 22 are arranged so as to be rotatable around the rotation shaft 25a, the first platen 21 and the second platen 22 can be rotated from the substrate S on the first platen 21 only by rotating the rotation shaft 25a. The ion implantation process can be promptly transferred to the substrate S on the second platen 22.

  As described above, according to the present embodiment, since the waiting time required for the pre-heat treatment of the substrate S can be shortened, the throughput of the ion implantation process performed at a high temperature is increased, and an improvement in the apparatus operating rate can be realized. . In addition, since it is possible to perform ion implantation at different temperatures on the substrates S on the first and second platens 21 and 22, there is no waiting time required for changing the temperature of the platen, thereby improving throughput. Can be planned.

  Further, since the first platen 21 and the second platen 22 are arranged at rotationally symmetric positions with respect to the rotation shaft 25a, the platens 21 and 22 can be moved only by the rotation operation of the rotation shaft 25a by the rotation mechanism 25. It can arrange | position to the irradiation position of an ion beam. Therefore, for example, it is not necessary to change the irradiation position for each platen by the beam irradiation source, and ions can be implanted into the substrate on each platen at a certain irradiation position. Such a configuration is particularly effective in an ion implantation apparatus in which the center of gravity of the ion beam irradiation area cannot be moved.

<Second Embodiment>
FIG. 4 is a side view of the main part showing the configuration of the platen unit in the ion implantation apparatus according to the second embodiment of the present invention. Hereinafter, configurations different from those of the first embodiment will be mainly described, and configurations similar to those of the above-described embodiment will be denoted by the same reference numerals, and description thereof will be omitted or simplified.

  The platen unit 300 of the present embodiment is different from the first embodiment in that the number of platens is three. That is, in the present embodiment, the platen unit 300 includes the first platen 31, the second platen 32, and the third platen 33. The platens 31 to 33 are integrally fixed via a support member 34.

  The support member 34 is connected to the rotation shaft 25a of the rotation mechanism section, and the platens 31 to 33 are arranged around the rotation shaft 25a with an interval of 120 °. Each of the platens 31 to 33 is disposed on the support member 34 such that the normal line of each holding surface is parallel to the YZ plane (first plane).

  In the present embodiment, the holding surfaces of the platens 31 to 33 are configured with an area smaller than the area of the substrate S. However, the present invention is not limited to this, and the area is larger than the area of the substrate S as in the first embodiment. You may comprise by area.

  In the present embodiment, the platens 31 to 33 are disposed at rotationally symmetric positions with respect to the rotation shaft 25a. The rotation mechanism unit is configured to be able to place any one of the first to third platens 31 to 33 at the irradiation position of the ion beam by rotating the rotation shaft 25a.

  Each of the platens 31 to 33 incorporates temperature adjustment mechanisms 31b, 32b, and 33b, and is configured to be able to heat or cool the substrate on each holding surface to a predetermined temperature.

  The temperature adjustment mechanisms 31b, 32b, and 33b may be heater units that heat the holding surface, or may be cooling units that cool the holding surface. Moreover, it is not restricted to when each platen has the same temperature control mechanism, One platen may have a heater unit and the other platen may each have a cooling unit. For example, the temperature adjustment mechanisms 31b and 32b may be constituted by heater units, and the temperature adjustment mechanism 33b may be constituted by a cooling unit. Accordingly, for example, it is possible to perform a process of performing ion implantation at a high temperature and a process of performing ion implantation at a normal temperature with a single apparatus.

  Also in the ion implantation apparatus of the present embodiment configured as described above, the same operational effects as those of the first embodiment described above can be obtained. In addition, according to the present embodiment, the number of substrates that can be held at one time can be increased, so that the productivity can be further improved.

  The embodiment of the present invention has been described above, but the present invention is not limited to the above-described embodiment, and it is needless to say that various modifications can be made without departing from the gist of the present invention.

  For example, in the first and second embodiments described above, the case where the number of platens is two and three has been described as an example, but the present invention is not limited to this, and the number of platens may be four. In this case, the platens are arranged at intervals of 90 ° around the rotation shaft 25a. The plurality of platens are not limited to an example in which the platens are arranged at equiangular intervals around the rotation axis.

  In each of the above embodiments, the apparatus configuration in which ions are implanted into the substrate S using a ribbon-like ion beam scanned with an ion beam in a uniaxial direction has been described. However, the present invention is not limited to this, and a linear ion beam is used. The present invention is also applicable to an apparatus configuration in which ions are implanted while scanning in the biaxial direction.

  Further, in the above first embodiment, the temperature adjustment mechanisms 21b and 22b of the first and second platens 21 and 22 are both configured as heater units, but either one is configured as a cooling unit. May be. Accordingly, it is possible to perform a process of performing ion implantation at a high temperature and a process of performing ion implantation at a normal temperature with a single apparatus.

1D... Ion beam 21, 22, 31, 32, 33... Platen 21a, 22a. ... Feed screw 80 ... End station 100 ... Ion implanter S ... Substrate

Claims (8)

A beam irradiation source configured to be capable of emitting an ion beam;
A plurality of platens each having a holding surface configured to hold a substrate;
A support member that supports the plurality of platens such that a normal line of each of the holding surfaces is parallel to the first plane;
A rotation axis connected to the support member and extending in a first axial direction perpendicular to the first plane is configured to be able to place any one of the plurality of platens at the ion beam irradiation position. An ion implantation apparatus comprising: a rotation mechanism unit. The ion implantation apparatus according to claim 1,
An ion implantation apparatus further comprising: a linear movement mechanism that is capable of reciprocating the support member in a second axial direction orthogonal to the first axial direction. The ion implantation apparatus according to claim 2,
The beam irradiation source includes a beam scanning unit capable of scanning the ion beam in the first axial direction. The ion implantation apparatus according to claim 2,
The ion beam irradiation source is configured to be capable of emitting a ribbon-like ion beam parallel to a second plane orthogonal to the first plane. The ion implantation apparatus according to any one of claims 1 to 4,
Each of the plurality of platens further includes a temperature adjustment mechanism capable of adjusting the temperature of the holding surface. An ion implantation apparatus according to any one of claims 1 to 5,
The plurality of platens are arranged at rotationally symmetric positions with respect to the rotation axis. The ion implantation apparatus according to any one of claims 1 to 6,
The plurality of platens include first and second platens disposed at intervals of 180 ° around the rotation axis. The ion implantation apparatus according to any one of claims 1 to 6,
The plurality of platens include first, second, and third platens disposed at intervals of 120 ° around the rotation axis. Ion implantation apparatus.

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