JP6036743B2 - Ion implanter - Google Patents

Description

  The present invention relates to an ion implantation apparatus for implanting ions into a target such as a wafer.

  As this type of ion implantation apparatus, as shown in Patent Document 1, an apparatus including an electrostatic clamp mechanism that holds a wafer by being attracted by an electrostatic chuck and a mechanical clamp mechanism that mechanically holds the wafer. Are known.

  Here, when the wafer becomes high temperature (about 1000 degrees), the adsorption force by the electrostatic chuck decreases, and the above-described ion implantation apparatus has a temperature sensor for measuring the temperature of the wafer, and the measurement temperature obtained by the temperature sensor. The mechanical clamp mechanism is driven to hold the wafer when the value exceeds a predetermined value.

  However, a power mechanism such as an actuator used for a mechanical clamp mechanism generally does not have heat resistance that can withstand the above-described temperature. Therefore, the power mechanism becomes a neck and space, weight, vacuum state, There are restrictions on the use environment such as the use temperature, restrictions on the operating conditions such as the timing and speed of holding the wafer, and it is necessary to use an expensive driving force with high heat resistance.

Special table 2013-53374 gazette

  Accordingly, the present invention has been made to solve the above-mentioned problems all at once, and has as its main subject to hold a target such as a wafer with a simple configuration without using a power mechanism.

That is, the ion implantation apparatus according to the present invention is an ion implantation apparatus for implanting ions into a target, and includes a placement position where the target is placed and an implantation position where ions are implanted into the placed target. A mounting table that moves between the above, and a mechanical type that is provided on the mounting table and is switched to a holding state that holds the target or an open state that does not hold the target by being partially pressed by the movement of the mounting table A clamping mechanism, and the mechanical clamping mechanism has a holding member that moves between a holding position that holds the target with the mounting table and an open position that does not hold the target. , the holding member from the placing position before the mounting table during the movement to the injection position is moved to the holding position from the open position or the injection position In which the retaining member during movement to the placement position is thus being moved to the open position from the holding position.

If this is the case, the mechanical clamp mechanism is switched to the holding state or the open state by being partially pressed by the movement of the mounting table, so that the power mechanism such as an actuator for moving the mechanical clamp mechanism. And the target can be held with a simple configuration, and the entire apparatus can be made inexpensive and compact.
Furthermore, this ion implantation apparatus eliminates the need for a power mechanism, so that it is not necessary to impose restrictions due to the use of the power mechanism, and the operating conditions of the apparatus can be widened.

Here, when the target is attracted and fixed by the electrostatic chuck, when the treated target is peeled off from the mounting table, if the attracting voltage is turned off and immediately removed, the target is forcibly pulled by the residual attracting force. The wafer will be peeled off and the wafer will break or jump.
In order to avoid such a problem, conventionally, the target is peeled off after a certain time until the residual attracting force decreases, or a residual voltage is applied by applying a voltage having a polarity opposite to the attracting voltage before the peeling. The adsorptive power was reduced, resulting in a reduction in processing capacity per unit time.
On the other hand, according to the above-described ion implantation apparatus according to the present invention, since the mechanical clamp mechanism holds the target, the problem due to the residual adsorption force does not occur, and the processed target is immediately peeled off from the mounting table. And the processing capacity of the apparatus can be improved.

Further, when the target is processed at a high temperature, if the target is attracted and fixed by the electrostatic chuck as described above, thermal stress is generated due to thermal deformation of the target, and the target may be warped or cracked. There is.
In order to avoid such a problem, conventionally, for example, electrostatic chucking is performed after a time until the thermal deformation of the target decreases, and this also causes a decrease in processing capacity per unit time. .
On the other hand, according to the above-described ion implantation apparatus according to the present invention, since the mechanical clamp mechanism holds a part of the target, for example, around the target, almost the entire surface of the target is fixed like an electrostatic chuck. In this way, the thermal deformation of the target can be easily released. Thereby, even if a target is high temperature, the thermal stress which arises when the said target is fixed can be reduced, and it can make it hard to produce a curvature and a crack.

As a specific embodiment in which the effect of the present invention is particularly remarkable, there is further provided a tilt angle changing mechanism that changes the tilt angle of the target by tilting the mounting table between the mounting position and the injection position. And the mechanical clamp mechanism is switched to the holding state or the open state by the movement of the mounting table by the tilt angle changing mechanism.
In this case, when the target is at a high temperature and the chucking force by the electrostatic chuck is low, even if the mounting table is tilted by the tilt angle changing mechanism, the mechanical clamp mechanism is held by the movement of the mounting table by the tilt angle changing mechanism. Or since it switches to an open state, it can hold | maintain a target reliably and can prevent dropping and position shift.

  As a specific embodiment in which the mechanical clamp mechanism has a simple configuration while eliminating the need for a power mechanism such as an actuator, the mechanical clamp mechanism has a holding position where the target is held and an open position where the target is not held And a holding member that moves between the holding member and a member that is directly or indirectly connected to the holding member, and is pressed against the outside of the mechanical clamp mechanism by the movement of the mounting table. The holding member is moved between the holding position and the open position, and is switched between the holding state and the open state when the pressing portion is pressed to the outside. Things.

It is preferable that the mounting table has an electrostatic clamping mechanism that electrostatically chucks the target.
In this case, for example, the target can be more reliably held by using both the electrostatic clamp mechanism and the mechanical clamp mechanism.

What has a drop-off prevention member which is provided outside the mounting table and prevents the target mounted on the mounting table from dropping from the mounting table is preferable.
If this is the case, even if the mechanical clamp mechanism enters the holding state with a delay after the mounting table is tilted, the target can be prevented from falling off the mounting table.

  According to the present invention configured as described above, the target can be held with a simple configuration without using a power mechanism, and the entire apparatus can be made inexpensive and compact without being restricted by the power mechanism. In addition, the processing capacity of the apparatus does not decrease depending on the temperature of the target.

The figure which shows typically the structure of the ion implantation apparatus of this embodiment. The figure which shows typically the structure of the mounting base of the embodiment. The figure which shows the mechanical clamp mechanism of the embodiment. The figure which shows the mechanical clamp mechanism of the embodiment. The flowchart which shows operation | movement of the ion implantation apparatus of the embodiment.

  Hereinafter, an embodiment of an ion implantation apparatus according to the present invention will be described with reference to the drawings.

The ion implantation apparatus 100 according to the present embodiment performs ion implantation by making an ion beam IB incident on a target W placed on a mounting table 200.
Specifically, as shown in FIG. 1, the ion implantation apparatus 100 includes an ion source 101 that generates an ion beam that is a source of a ribbon-shaped beam IB, and predetermined ions from an ion beam emitted from the ion source 101. Analyzing electromagnet 102 that sorts and derives the ion beam of the seed, acceleration / decelerator 103 that accelerates / decelerates the ion beam derived from this analyzing electromagnet 102 to a predetermined energy, and derived from this accelerometer 103. An energy separator 104 that selects and derives an ion beam having a predetermined energy from the ion beam, a scanner 105 that reciprocally scans the ion beam derived from the energy separator 104 by an electric field or a magnetic field, and the scanner 105 A parallel scan of the ion beam derived from is performed to form an ion beam IB having a ribbon shape That and a beam collimator 106.

  The target W is, for example, a semiconductor substrate such as a silicon substrate, a glass substrate, or another substrate. In the present embodiment, the planar shape is a substantially circular shape as shown in FIG. 2, but may be a substantially rectangular shape or other shapes.

The mounting table 200 is used for mounting a target W transported by a target transporting device (not shown). As shown in FIGS. 2 and 3, the upper surface is formed as a mounting surface 21 on which the target W is mounted. ing.
The mounting table 200 of the present embodiment has an electrostatic clamp mechanism (not shown) that attracts and fixes the target W mounted on the mounting surface 21 by an electrostatic chuck.
Further, the mounting table 200 of the present embodiment includes a heating unit (not shown) that heats the mounted target W to a desired temperature. The heating unit is configured to heat at least the mounting surface 21 described above and raise the temperature of the target W to about 400 degrees to 600 degrees.

A heat shield 3 and a cooling plate 4 are provided below the mounting table 200 as shown in FIG.
The heat shield 3 and the cooling plate 4 suppress the transfer of the heat from the mounting surface 21 heated by the heating unit to the lower member. Specifically, the heat shield 3 is made of carbon. It is a thin plate. In the present embodiment, the plurality of heat shields 3 are overlapped and arranged below the placement surface 21.

As shown in FIG. 2, a plurality of drop-off prevention members 5 are provided on the periphery of the mounting table 200.
The drop-off prevention member 5 prevents the target W from dropping from the mounting table 200. Specifically, the drop-off preventing member 5 has a rod-like shape provided in the circumferential direction around the target W on the mounting table 200. It is.
More specifically, the drop-off prevention member 5 is formed with a tapered surface inclined toward the center of the mounting surface 21 from the upper part toward the lower part on the surface facing the mounting surface 21 on the outer peripheral surface. Yes, the target W is positioned with respect to the mounting surface 21 by mounting the target W on the mounting table 200 along the tapered surface.

As shown in FIG. 4, the mounting table 200 described above is configured to move between a mounting position P where the target W is mounted and an implantation position Q where ions are implanted into the mounted target W. Has been.
In the present embodiment, the mounting table 200 at the mounting position P is in a substantially horizontal state so that the target W is mounted on the mounting table 200 in a substantially horizontal state.

  As a mechanism for moving the mounting table 200 from the mounting position P to the implantation position Q, the ion implantation apparatus 100 of this embodiment includes a translation mechanism (not shown) that translates the mounting table 200 and a rotational movement that tilts the mounting table 200. And a tilt angle changing mechanism 6.

A translation mechanism (not shown) moves the mounting table 200 in a substantially horizontal state from the mounting position P to, for example, a predetermined intermediate position positioned above the mounting position P.
Note that the translation mechanism of the present embodiment integrally moves at least the mounting table 200, the tilt angle changing mechanism 6, and a mechanical clamp mechanism 700 described later.

The tilt angle changing mechanism 6 changes the tilt angle of the target W mounted on the mounting table 200 by tilting the mounting table 200 at a predetermined position between the mounting position P and the injection position Q. In the embodiment, the mounting table 200 at the intermediate position is tilted and moved to the injection position Q, and the mounting table 200 at the injection position Q is made substantially horizontal and returned to the intermediate position.
Specifically, as shown in FIG. 4, the tilt angle changing mechanism 6 is provided below the mounting table 200, and the mounting table 200 is in a substantially horizontal state and a non-horizontal state in which the tilting angle is inclined by a predetermined angle from the substantially horizontal state. It is comprised so that it may move between.
In the present embodiment, at the implantation position Q, the target W on the mounting table 200 is in a non-horizontal state, and the target beam W is irradiated with the ion beam IB at a predetermined angle.

As shown in FIGS. 2 to 4, the ion implantation apparatus 100 according to the present embodiment is provided on the mounting table 200 described above, and a part of the mounting table 200 is pressed against the target W by moving the mounting table 200. A mechanical clamp mechanism 700 that switches to a holding state in which the target W is held or an open state in which the target W is not held is provided.
More specifically, the mechanical clamp mechanism 700 is configured such that a part of the mechanical clamp mechanism 700 is pressed by the movement of the mounting table 200 by the tilt angle changing mechanism 6 described above, and the state is switched to a holding state or an open state.

Specifically, as shown in FIGS. 3 and 4, the mechanical clamp mechanism 700 is connected to the holding member 71 that holds the target W, the holding member 71, and the mechanical table is moved by the movement of the mounting table 200. And a pressing member 72 pressed against the outside of the clamp mechanism 700.
The mechanical clamp mechanism 700 of this embodiment includes a plurality of holding members 71. Specifically, as shown in FIGS. 2 and 3, the two holding members 71 are arranged in the radial direction of the target W. It is provided opposite to each other on both sides.

As shown in FIGS. 3 and 4, the holding member 71 moves between a holding position x that holds the target W and an open position y that does not hold the target W. In the present embodiment, the holding member 71 or It is provided on a member integral with the mounting table 200 and is configured to rotate with respect to the mounting table 200 to move between the holding position x and the opening position y.
Specifically, the holding member 71 is provided with a holding claw 711 at its upper end, and rotates around a predetermined rotation axis C so that the holding claw 711 contacts the target W at the holding position x and is released. The holding claw 711 is configured not to contact the target W at the position y.

  The holding claw 711 is in contact with the outer peripheral portion of the target W at the holding position x and holds the target W with the mounting table 200. Specifically, as shown in FIG. None, the planar shape is a shape in which the tip is cut out in an arc shape, and in the present embodiment, for example, it has carbon conductivity.

The pressing member 72 is directly connected to the lower end portion of the holding member 71, and rotates the holding member 71 described above around a predetermined rotation axis C by being pressed to the outside of the mechanical clamp mechanism 700. Thus, it is moved between the holding position x and the opening position y.
Specifically, as shown in FIG. 4, the pressing member 72 has a long shape, and a pressing portion 721 is provided at the distal end portion thereof, and the mounting table 200 moves to the mounting position P. The pressing portion 721 is configured to be pressed against the contact portion 8 located outside the mechanical clamp mechanism 700.

  In the present embodiment, an elastic member 73 is attached to the holding member 71 as shown in FIG. The elastic member 73 urges the holding member 71 to the holding position x. Specifically, the mounting table 200 or a member integrated with the mounting table 200 (in this embodiment, the cooling plate 4) and the holding member. 71 is a spring member connected to 71.

  Next, the operation of the ion implantation apparatus 100 of the present embodiment will be described with reference to the flowchart of FIG.

First, a target transport device (not shown) places the target W on the placement table 200 that is in a substantially horizontal state at the placement position P (S1).
More specifically, the target W is lowered from above the mounting table 200 along the tapered surface of the drop-off prevention member 5 provided on the periphery of the mounting table 200, and the center of the mounting surface 21 of the mounting table 200 and the target W The target W is placed on the placement surface 21 so that the center of the substrate substantially coincides.
In this mounting position P, the pressing portion 721 is pressed against the abutting portion 8 and the mechanical clamp mechanism 700 is in an open state.

Next, an electrostatic clamp mechanism (not shown) attracts and fixes the target W placed on the placement surface 21 with an electrostatic chuck (S2).
In addition, the electrostatic clamp mechanism at this time should just adsorb | suck the target W to such an extent that the target W does not shift | deviate with respect to the substantially horizontal mounting surface 21. FIG.

  Subsequently, a translation mechanism (not shown) translates the mounting table 200 to move it from the mounting position P to a predetermined intermediate position (S3).

  When the mounting table 200 reaches the intermediate position, the tilt angle changing mechanism 6 tilts the mounting table 200 to change the tilt angle of the target W mounted on the mounting table 200 to a predetermined angle (S4).

When the mounting table 200 starts to be tilted from the substantially horizontal state by the tilt angle changing mechanism 6, the above-described pressing portion 721 and the contact portion 8 are in contact with each other until the tilt is changed by a predetermined angle (for example, 5 degrees). When the mounting table 200 is tilted by the predetermined angle and immediately before the pressing portion 721 and the abutting portion 8 are separated from each other, the contacting portion 721 and the abutting portion 8 are in contact with each other.
From this contact state, the mounting table 200 is further tilted and moved to the injection position Q by the tilt angle changing mechanism 6, whereby the pressing portion 721 starts to be separated from the contact portion 8. The holding member 71 connected to the member 72 rotates about the rotation axis C and moves from the open position y to the holding position x. Thereby, the mechanical clamp mechanism 700 switches from the open state to the holding state (S5).

  Thereafter, the mounting table 200 is further tilted by the tilt angle changing mechanism 6 and moved to the injection position Q. At the injection position Q, a heating unit (not shown) starts heating the target W on the mounting table 200 (S6).

  When the temperature of the target W rises to a predetermined temperature (for example, 500 degrees) by the heating unit, ion implantation is performed by irradiating the target W with the ion beam IB (S7).

  When the ion implantation is completed, the tilt angle changing mechanism 6 again tilts the mounting table 200 and moves the mounting table 200 from the implantation position Q to the intermediate position (S8).

  Along with this movement, immediately before the mounting table 200 reaches the intermediate position, that is, immediately before the mounting table 200 becomes in a substantially horizontal state (for example, a state tilted by 5 degrees), the pressing unit 721 and the contact unit 8 again. Are in contact with each other (S9).

  From this contact state, when the mounting table 200 is further tilted and moved to the intermediate position by the tilt angle changing mechanism 6, the pressing portion 721 is pressed against the contact portion 8 and is connected to the pressing member 72. The holding member 71 rotates about the rotation axis C and moves from the holding position x to the open position y. As a result, the mechanical clamp mechanism 700 is switched from the holding state to the open state (S10).

  In this state, a translation mechanism (not shown) translates the mounting table 200 and moves it from the predetermined intermediate position to the mounting position P (S11).

  After the mounting table 200 reaches the mounting position P, the electrostatic chuck by the electrostatic clamping mechanism (not shown) is released (S12).

  Finally, a target transport device (not shown) lifts the target W on the mounting table 200 and transports it to a predetermined position (S13).

  Thereafter, the operations from S1 to S13 are repeated to process a plurality of targets W continuously.

According to the ion implantation apparatus 100 according to the present embodiment configured as described above, the pressing member 72 is pressed against the contact portion 8 by the movement of the mounting table 200, so that the mechanical clamp mechanism 700 is held or Since it is switched to the open state, a power mechanism such as an actuator for moving the mechanical clamp mechanism 700 is not required, and the target W can be held with a simple configuration, and the entire apparatus can be made inexpensive and compact.
Furthermore, this ion implantation apparatus 100 eliminates the need for a power mechanism, so that it is not necessary to impose restrictions or conditions due to the use of the power mechanism, and the operating condition range of the apparatus can be widened.

  In addition, since the mechanical clamp mechanism 700 holds the target W, problems that may occur conventionally due to the temperature of the target W (for example, a decrease in holding force due to the electrostatic clamp mechanism or cracking of the target W due to thermal deformation). Etc.) is extremely difficult to occur.

  Further, since the holding claws 711 are made of carbon having conductivity, the cost is low and the wafer is less contaminated.

  In addition, even if the mechanical clamp mechanism 700 is held in a delayed state after the mounting table 200 is tilted, the dropout prevention member 5 is provided on the outer periphery of the mounting table 200, so that the target W is placed on the mounting table 200. It is possible to prevent dropping from 200.

  The present invention is not limited to the above embodiment.

For example, the mechanical clamp mechanism of the above embodiment is configured to switch from the holding state to the open state when a part thereof is pressed, but from the open state when the part is pressed. You may be comprised so that it may switch to a holding state.
In this case, as a specific configuration, for example, the elastic member biases the holding member to the open position, and the holding member is pressed to the outside, so that the holding member is centered on a predetermined rotation axis. Examples include those configured to rotate and move from the open position to the holding position.

  Moreover, in the said embodiment, although the pressing part was provided in the front-end | tip part of the pressing member connected with the holding member, the structure which provided the pressing part in the holding member may be sufficient.

  Furthermore, although the pressing member of the said embodiment was directly connected with the holding member, it may be indirectly connected through the link member etc., for example.

  In addition, in the above-described embodiment, a plurality of holding members are provided at positions facing each other. However, it is not always necessary to provide the holding members at positions facing each other. Furthermore, three or more holding members can be provided for more reliable holding. You may comprise as follows.

  In addition, in the said embodiment, although the mounting base was comprised so that it might become a substantially horizontal state in a mounting position, you may make it become a non-horizontal state in a mounting position.

  The heating unit provided on the mounting table of the embodiment is for heating the target to 400 to 600 degrees. However, the temperature of the target is not limited to the above-described range, for example, about 1000 degrees. The heating may be performed, or the target may not be heated without operating the heating unit.

  Although the mounting table of the embodiment includes an electrostatic clamp mechanism, it is not always necessary to attract the target with an electrostatic chuck.

Moreover, in the said embodiment, while moving a mounting base from a mounting position to an injection | pouring position, it is tilted (rotated and moved) after translation, but it is tilted (rotated and moved). You may make it move in translation.
More specifically, the tilt angle changing mechanism rotates and moves the mounting table at the mounting position to the intermediate position, and then the translation mechanism moves the mounting table at the intermediate position, for example, at the injection position above the intermediate position. You may comprise so that it may translate to.

  Further, during the period from the placement position to the injection position, the placement table is moved by the tilt angle changing mechanism or the translation mechanism, for example, by moving the placement table in a translational manner, then rotating the translation table and further moving the translation table. May be performed multiple times.

  In addition, it goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

W ... Target 100 ... Ion implantation apparatus 200 ... Place 6 ... Tilt angle changing mechanism 700 ... Mechanical clamp mechanism 71 ... Holding member 72 ... Pushing member P ...・ Installation position Q ・ ・ ・ Injection position x ・ ・ ・ Holding position y ・ ・ ・ Open position

Claims (5)

An ion implantation apparatus for implanting ions into a target,
A mounting table that moves between a mounting position where the target is mounted and an implantation position where ions are implanted into the mounted target;
A mechanical clamp mechanism that is provided on the mounting table and is switched to a holding state that holds the target or an open state that does not hold the target by being partially pressed by the movement of the mounting table;
The mechanical clamp mechanism has a holding member that moves between a holding position that holds the target with the mounting table and an open position that does not hold the target;
Moved from the holding member the open position from the placement position during movement to the injection position of the mounting table in the holding position, the holding member during said movement to the placement position from the injection position An ion implantation apparatus that moves from a holding position to the open position . Further comprising a tilt angle changing mechanism for changing the tilt angle of the target by tilting the mounting table between the mounting position and the injection position;
The ion implantation apparatus according to claim 1, wherein the mechanical clamping mechanism is switched to the holding state or the opened state by the movement of the mounting table by the tilt angle changing mechanism. The mechanical clamp mechanism is
Provided on the holding member or a member that is directly or indirectly connected to the holding member, comprising a pressing portion that is pressed to the outside of the mechanical clamp mechanism by the movement of the mounting table,
The said holding | maintenance member moves between the said holding | maintenance position and the said open | release position, and switches to the said holding | maintenance state and the said open | release state by the said pressing part pressing against the exterior. Ion implanter.   The ion implantation apparatus according to claim 1, wherein the mounting table includes an electrostatic clamping mechanism that electrostatically chucks the target. The ion implantation apparatus according to any one of claims 1 to 4, further comprising a drop-off preventing member that is provided outside the mounting table and prevents the target mounted on the mounting table from dropping from the mounting table. .