JPH0770298B2 - Ion implanter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention electrically scans an ion beam and
The present invention relates to a so-called hybrid scan type ion implantation apparatus which mechanically scans a wafer in a direction substantially orthogonal thereto.

[Conventional technology]

 A conventional example of this type of ion implantation apparatus is shown in FIG.

That is, the ion beam 2 is X-rayed by a scanning means (not shown).
In the implantation chamber, a holder 150 for holding the wafer 4 is provided in the implantation chamber while being electrically scanned in a direction (for example, a horizontal direction; the same applies hereinafter) and guided into the implantation chamber (not shown). Mechanical scanning is performed in the X direction (for example, the vertical direction; the same applies hereinafter) orthogonal to the X direction.

The holder driving device 156 simply puts the holder raising device 152 and the holder 150, which rotate the holder 150 between the vertical state for ion implantation into the wafer 4 and the horizontal state for handling the wafer 4, into the holder. A holder elevating device 154 that elevates and lowers in the Y direction and mechanically scans is provided together with the erecting device 152.

[Problems to be Solved by the Invention]

However, according to the above-described configuration, as the holder elevating / lowering device 154, since the mechanism that converts the rotational movement by the motor into the linear movement by using, for example, a worm gear is used, the stroke becomes long, and the entire mechanism is changed. If it is housed in the implantation chamber, the vacuum container becomes large, which leads to an increase in the size of this type of ion implantation apparatus.

Further, when the holder elevating / lowering device 154 is arranged in the atmosphere, the slide shaft 153 that moves linearly to move the holder 150 vertically moves between the injection chamber in vacuum and the atmosphere. It is necessary to consider that there is no such thing.
For example, a so-called dynamic vacuum in which the slide shaft 153 penetrating the vacuum container is configured to slide in a plurality of compartments in a non-contact state, and each room is operated and exhausted by a separate vacuum pump. Although a sealing method has been attempted, there is a problem in that the structure is extremely complicated and the ultimate vacuum of the injection chamber is poor, so that it is necessary to improve the capacity of the vacuum pump for the injection chamber.

Therefore, in view of the above matters, the present invention does not use the dynamic vacuum seal system as described above,
A rotary motion of a motor disposed in an arm injection chamber supporting a holder for holding a wafer causes the wafer to swing and rotate, thereby mechanically moving the wafer in a Y direction substantially orthogonal to an X direction in which an ion beam is scanned. It is a main object to provide an ion implanting device adapted to scan.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the ion implantation apparatus of the present invention is, to put it simply, an implantation chamber in which an ion beam electrically scanned in the X direction is guided, and a holder for holding a wafer in the implantation chamber. A holder driving device for mechanically scanning the holder in the Y direction substantially orthogonal to the X direction, and the holder driving device is provided in the arm supporting the holder and in the middle chamber. And a reversible direct drive motor for reciprocating the lever arm within a predetermined angle range.

In that case, the holder driving device may further include a second reversible direct drive motor attached to the arm, and the holder may be attached to an output shaft of the second direct drive motor.

Further, the holder driving device includes a bearing having a vacuum sealing function provided on the side wall of the injection chamber, a main shaft penetrating the bearing, and a third shaft in which an output shaft is coupled to an end of the main shaft outside the injection chamber. A direct drive motor may be further provided, and a direct drive motor for reciprocating the arm may be attached to an end of the main shaft on the inner side of the injection chamber.

Further, the ion beam may be electrically scanned in the X direction and a parallel beam may be applied.

A second holder for holding a wafer in the implantation chamber; and a second holder driving device for mechanically scanning the holder in the implantation chamber in a Y direction substantially orthogonal to the X direction. You may further provide what has the same structure as a holder drive device.

[Action]

According to the above configuration, when the direct drive motor for driving the arm of the holder driving device is rotated in the normal direction and the reverse direction, the arm is reciprocally swung. As a result, the holder supported by this arm is mechanically scanned with the wafer held therein in a Y-direction that is substantially orthogonal to the X-direction, which is the scanning direction of the ion beam, in a shape that draws an arc. .

〔Example〕

FIG. 1 is a horizontal sectional view showing a main part of an ion implantation apparatus according to an embodiment of the present invention. In this example, the same mechanism is provided substantially symmetrically on the left and right of the beam line of the ion beam 2, and hence the right side (right side in the figure) will be mainly described below in columns.

In this embodiment, an ion beam 2 which is electrically scanned in the X direction and converted into a parallel beam is introduced into an implantation chamber 6 which is evacuated by a vacuum pump (not shown).

FIG. 2 shows an example of the scanning means for converting the ion beam 2 into a parallel beam. That is, two sets of ion beams 2 extracted from the ion source 110 and subjected to mass analysis, acceleration, etc. as necessary are applied with scanning voltages (triangular wave voltage) in opposite polarities from the same scanning power supply 116. Scan electrodes 112 and 1
Scanning is performed in the X direction by the cooperation of 14, and a parallel beam is formed when the light is emitted from the scanning electrode 114. However, unlike this example, the ion beam 2 may be scanned using a magnetic field in the same manner as described above.

Returning to FIG. 1, two holder driving devices 120 having the same structure in this embodiment are provided on the left and right of the injection chamber 6 as described above.

The holder driving device 120 is characterized by including at least an arm 136 that supports the holder 8 and a reversible direct drive motor 132 that is provided in the injection chamber 6 and swings and rotates the arm 136. The swinging rotation is reciprocating turning within a predetermined angle range.

In each holder driving device 120, in this embodiment, a side wall of the injection chamber 6 receives a vacuum seal bearing 122 having a vacuum sealing function, and the spindle 124 is supported by penetrating it in the X direction.

A reversible direct drive motor (third direct drive motor) 126 is attached to the outside of the injection chamber 6, and its output shaft 127 is directly connected to the main shaft by a coupling plate 128 without using a gear. It is connected to the outer end of the injection chamber of 124.

On the other hand, a reversible direct drive motor (first direct drive motor) 132 is connected to an end of the main shaft 124 on the injection chamber side via a coupling 130 so that its output shaft 133 is substantially orthogonal to the main shaft 124. Is attached to. As shown in FIG. 1, the output shaft 133 of the direct drive motor 132 can take a posture substantially parallel to the traveling direction of the ion beam 2 by rotating the main shaft 124 in the state shown in the drawing.

The direct drive motor 132 is vacuum sealed, for example, by an O-ring (not shown) inside and outside so that it can be brought into a vacuum, and the output shaft 133 and the motor case also contain, for example, a magnetic fluid. It is vacuum-sealed by the vacuum-sealing portion 134.

And the output shaft 133 of this direct drive motor 132
In addition, the arm 136 is directly attached without using something like a gear.

A reversible direct drive motor (second direct drive motor) 138 is attached to the tip of the arm 136 so that its output shaft 139 is substantially orthogonal to the arm 136.

This direct drive motor 138 also has an O-ring (not shown) inside and outside so that it can be brought into a vacuum.
Is vacuum-sealed by a vacuum seal portion 14 including a magnetic fluid between the output shaft 139 and the motor case.
Vacuum sealed by 0.

And the output shaft 139 of this direct drive motor 138
In addition, the holder 8 for holding the wafer 4 is directly attached so as to be substantially orthogonal to it without using a gear or the like. Therefore, the surface of the wafer 4 held by the holder 8 can be directed to the ion beam 2 as shown in FIG. The holder 8 is the base 8a in this example.
And the wafer retainer 8b that holds the wafer 4 between it and
And a wafer receiver 8c for moving the wafer 4 up and down.

According to the above structure, the main drive shaft 126 is rotated by the direct drive motor 126 as shown by an arrow D, and the holder 8 attached via the arm 136 or the like is mounted at a predetermined injection angle position (see FIG. 1). It can be driven to a holder 8 on the right side) and a horizontal position for handling the wafer 4 (see the holder 8 on the left side in FIG. 1).

Then, at the injection angle position, the direct drive motor 13
When 2 is rotated forward and backward as indicated by arrow E to swing and rotate the arm 136, that is, when the arm 136 is reciprocally swung within a predetermined angle range in a plane substantially orthogonal to the output shaft 133 of the direct drive motor 132. The holder 8 attached to the tip of the arm 136 is mounted on the wafer 4 held by the holder 8.
Is directed toward the ion beam 2 and is mechanically reciprocally scanned in a Y-direction substantially orthogonal to the X-direction in a form of drawing an arc (see also FIG. 3).

Moreover, at that time, when the direct drive motor 138 is rotated simultaneously with the direct drive motor 132 in the same direction (viewed from the output shaft side of each motor) and at the same angle, the holder 8 draws an arc as shown in FIG. Even when the holder is scanned, the absolute rotation of the holder 8 is 0 ° and its posture is unchanged. Therefore, the attitude of the wafer 4 mounted on the holder 8 is also unchanged (for example, the orientation flat 4a of the wafer 4 in FIG. 3 always faces upward regardless of the scanning position of the holder 8).

To drive both direct drive motors 132 and 138 as described above, the same pulse may be supplied to both.

Regarding the control of the arm 136, for example, if the angular velocity of the arm 136 is controlled so that the vertical velocity component of the holder 8 is proportional to the beam current of the ion beam 2, ion implantation with a uniform dose amount within the plane of the wafer 4 becomes possible. Become.

In addition, as in this embodiment, the direct drive motor 138
It is not essential to provide a constant attitude of the wafer 4 at the time of mechanical scanning, but if the attitude is fixed, a problem due to a change in the attitude of the wafer 4, for example, the wafer 4 swings in the arm 46. The rotation slightly causes a difference in the dose amount between the central portion and the peripheral portion (more specifically, the former amount increases), and when the ion beam 2 is not a parallel beam, the crystal of the wafer 4 It is possible to prevent the implantation angle from being changed and the implantation depth of the ions to be varied, thereby further improving the uniformity of implantation such as the dose amount and the implantation depth within the wafer surface.

In addition, the holder 8 is driven by the direct drive motor 138.
The in-on beam 2 is rotated by rotating the
It is also possible to perform ion implantation (that is, step rotation implantation) while changing the rotation angle of the wafer with respect to each other by a predetermined angle.

Further, it is not essential to form the ion beam 2 into a parallel beam as in this embodiment, but when the ion beam 2 is formed into a parallel beam, a problem due to the ion beam being scanned at an angle, for example, at each point on the wafer 4 When the incident angle of the ion beam is different and the three-dimensional structure is formed on the wafer, it is possible to prevent the shadow from being formed differently depending on the location, and thus the uniformity of the implantation within the wafer surface. Is further improved.

Further, according to this embodiment, the direct drive motor
It is also possible to change the implantation angle of the ion beam 2 with respect to the wafer 4 by changing the angle of the arm 136 and the holder 8 or the like with respect to the ion beam 2 by 126.

In order to move the holder 8 to the handling position of the wafer 4 as shown on the left side in FIG. Just go.

In this case, the direct drive motor 126 is located outside the injection chamber 6, that is, on the atmospheric pressure side.
The vacuum seal of the portion that is transmitted to the inside is a vacuum seal bearing 122 that vacuum seals the rotating shaft, and its configuration is extremely simple.

Further, in the case of flowing the coolant through the holder 8 in order to cool the wafer 4 on the holder 8, the following may be done.

That is, each direct drive motor 126, 132 and 138
Since a through hole is formed in the center of the holder 8, a holder shaft having a refrigerant passage is attached to the center of the holder 8, the holder shaft is passed through the center hole of the direct drive motor 138, and the rotary joint provided in the arm 136 is provided. Refrigerant is supplied to and collected from the holder shaft that rotates with, and a flexible tube is connected to this rotary joint to pass each through the center hole of the direct drive motor 132, and the center hole of the direct drive motor 126. It suffices that the main shaft 124 penetrating through is hollow and the tube is drawn through to the atmosphere side to supply and recover the refrigerant from the atmosphere side.

By the way, in this embodiment, the wafer 4 is placed between the inside of the injection chamber 6 and the atmosphere side at the bottoms on the left and right of the rear portion of the inside entrance chamber 6.
Adjacent vacuum preparatory chambers 80 for loading and unloading (unloading and loading) one by one.

4 and 5 are cross-sectional views of this vacuum preliminary chamber 80. FIG. 4 shows a state in which the vacuum side valve 88 of the vacuum reserve chamber 80 is closed and the atmosphere side valve 90 is open, and FIG. 5 shows a state in which the vacuum side valve 8 is open and the atmosphere side valve 90 is closed. However, in FIG. 5, a part of the wafer transfer device 60 to be post-processed is also shown for convenience.

More specifically, a vacuum preliminary chamber 80, which is evacuated by a vacuum pump 92, is provided at the bottom of the injection chamber 6, a vacuum side valve 88 for partitioning the space from the injection chamber 6 is provided at the upper portion, and a vacuum side valve 88 is provided at the lower portion. Atmosphere-side valves 90 for partitioning the atmosphere side are provided respectively.

The vacuum-side valve 88 is lifted and lowered by an air cylinder 86 provided on the injection chamber 6, and the atmosphere-side valve 90 is lifted and lowered by a lower air cylinder 102 via a guide shaft 98. The lever 88 and the air cylinder 82 provided above the air cylinder 86 are for locking the air cylinder 86.

A rotary table 94 on which the wafer 4 is placed is provided above the atmosphere side valve 90. The rotary table 94 is rotated by a motor 96 for alignment of the wafer 4 orientation flat and the dual straw cylinder 100.
The wafer 4 is moved up and down in two steps for handling the wafer 4.

Returning to FIG. 1 again, a wafer transfer device 60 having the following structure is provided in a portion from each of the above vacuum preliminary chambers 80 to each of the holders 8 in the horizontal state.

That is, referring also to FIG. 6, the timing belt is provided between the two grooved pulleys 70 and 72 along the wafer 4 transfer path between the vacuum preliminary chamber 80 and the holder 8 in the horizontal state.
68 are looped around. A motor 74 capable of normal rotation and reverse rotation is connected to one pulley 70.
Then, a load-side transfer arm 61a and an unload-side transfer arm device 61b on which the wafer 4 can be mounted are attached to the upper and lower portions of the timing belt 68 via coupling fittings 66, respectively. Has been.

Further, a ball spline is adopted in this embodiment as a guide means for guiding the transfer arms 61a and 61b to move along the timing belt 68 without rotating.
That is, spline bearings are provided at the bases of the transfer arms 61a and 61b.
64a and 64b are attached, and upper and lower two spline shafts 62a and 62b penetrating them are arranged in parallel with the timing belt 68.

Instead of such a ball spline, two normal guide shafts may be used, but if a ball spline is used, a single spline shaft allows the transport arm to travel horizontally and stably without rotating. Can guide you.

Although each of the spline shafts 62a and 62b is shown as a round bar for simplification, it is actually a round bar shape or a different shape having a plurality of balls rolling grooves.

Next, an example of the overall operation of the ion implantation apparatus as described above will be described focusing on the mechanism on the right side of FIG.

The holder driving device 120 moves the holder 8 to a horizontal position (in this state, refer to the holder 8 on the left side in FIG. 1),
The wafer receiver 8c and the wafer retainer 8b are driven by a drive device (not shown) to raise the previously mounted wafer 4 to a position where it is delivered to the lower unloading transfer arm 61b.

On the other hand, on the side of the vacuum reserve chamber 80, referring to FIG. 5, both the upper and lower cylinders of the dual stroke cylinder 100 are operated to greatly raise the rotary base 94, and as shown by the double-dotted chain line, the upper load side The unimplanted wafer 4 is lifted up to the position of the transfer arm 61a, and in that state, the wafer transfer device 60
The motor 74 drives the timing belt 68 to simultaneously move the transfer arm 61a to the position on the vacuum preliminary chamber 80 and the transfer arm 61b to the position on the holder 8, and lower the wafer receiver 8c of the holder 8. Then, the wafer 4 that has been implanted is placed on the transfer arm 61b, and also on the vacuum preliminary chamber 80 side, the rotary table 94 is lowered to place the unimplanted wafer 4 on the transfer arm 61a.

Next, the motor 74 of the wafer transfer device 60 is reversed from the previous one, and the transfer arm 61b on which the injected wafer 4 is placed is placed on the vacuum preliminary chamber 80, and the transfer arm on which the uninjected wafer 4 is placed.
61a is moved onto the holder 8, and only the upper cylinder of the dual stroke cylinder 100 is operated on the side of the vacuum reserve chamber 80 to receive the wafer 4 from the transfer arm 61b by the rotary table 64 (state shown by the solid line in FIG. 5). ), On the holder 8 side, the wafer 4 is received from the transfer arm 61a by the wafer receiver 8c.

Next, the motor 74 of the wafer transfer device 60 is rotated in the reverse direction again to move both transfer arms 61a and 61b to the intermediate standby position (the state shown in FIG. 1), and the holder 8 side receives the wafer receiver 8c.
Then, the wafer retainer 8b is lowered to hold the wafer 4, and the holder driving device 120 moves the holder 8 to the implantation state as shown in FIG. 1 to complete the implantation preparation.

On the other hand, on the side of the vacuum reserve chamber 80, after lowering the rotary table 94 and closing the vacuum side valve 88, the inside of the vacuum reserve chamber 80 is returned to the atmospheric pressure state and the atmosphere side valve 90 is opened (see FIG. 4). (State), the wafer 4 that has been implanted is unloaded and the next unimplanted wafer 4 is loaded by the transfer arm device (not shown) on the atmosphere side.
At this time, in parallel, in the injection chamber 6, the holder driving device 12
While the holder 8 is mechanically scanned in the Y direction by 0 as described above, the wafer 4 on the holder 8 is irradiated with the ion beam 2 to perform ion implantation.

After that, the same operation as described above is repeated as necessary.

Although it is not essential to provide two holders 8 and two holder driving devices 120 so as to form a so-called dual type as in the above-described embodiment (that is, they may be one at a time), but if the type is a dual type, In parallel with performing ion implantation into the wafer 4 mounted on one of the holders 8 (for example, on the right side in FIG. 1) while scanning as described above, the other holder 8 is placed in a horizontal state and the wafer 4 (That is, taking out the implanted wafer 4 and mounting the unimplanted wafer 4) can be performed. That is,
The two holders 8 can alternately handle the ions 4 and the wafer 4, and the loss time of the ion implantation and the handling is almost eliminated, so that the throughput is improved.

Moreover, in the case of the dual type, it is simpler in structure and more compact and economical to have one beam line of the ion beam 2 (in other words, an electric scanning system of the ion beam 2), but In a conventional ion implanter as shown, another set of holder 150 and holder drive 156
Is to be symmetrically arranged with respect to the ion beam 2 with respect to the one shown in the drawing (that is, arranged downward on the upper side of the one shown in the drawing), the holder lifting / lowering device 154 only moves the holder 150 linearly up and down in the Y direction. The upper and lower holders 150 collide with each other, and in order to avoid this, the upper and lower holders 150 and the holder driving device 156 must be largely separated from each other, which makes the device huge. Moreover, since the handling (attachment / detachment) position of the wafer 4 with respect to the holder 150 is greatly different between the upper and lower holders 150, the wafer 4 transfer line has two upper and lower stages. The handling of the wafer 4 becomes very difficult because it must be done.

On the other hand, according to the above embodiment, since the arms 136 and the holder 8 move in an arc shape, the two holder driving devices 120 can be arranged close to each other while avoiding mechanical interference between them. Therefore, the ion implantation apparatus can be downsized. Further, since the wafers 4 can be handled with respect to the two holders 8 under the same conditions, for example, in this embodiment, the wafers 4 can be handled at the same height, and both of them can be placed with the surface of the wafer 4 facing up. It will be easier. As a result, it is possible to manufacture a dual-type ion implanter having a single beam line by the hybrid scan method and practical.

Further, an ion implanter of the same kind, which does not use a direct drive motor, has been previously proposed by the same applicant (Japanese Patent Application No. 1-19239), but the ion implanter of this embodiment is It has the following advantages.

That is, the ion implantation apparatus of the above application will be described with reference to FIGS. 7 and 8. In this ion implantation apparatus, for example, an ion beam 2 which is electrically scanned in the X direction and made into a parallel beam is introduced. Two holder driving devices 10 having the same structure are provided on the left and right of the injection chamber 6 to be formed.

In each holder drive device 10, a vacuum scene bearing 12 is attached to the side wall of the injection chamber 6, a support shaft 14 is penetrated through the same, and a gear 16 is attached to the atmosphere side thereof. To rotate and then the arm
The holder 8 attached via 46 is driven to a set implantation angle position and a horizontal position for handling the wafer 4.

On the vacuum side of the support shaft 14, a hollow arm shaft 40 and an arm 46 are rotatably supported by a vacuum seal bearing 38.

A pulley 36 is attached to one end of the arm shaft 40, and is connected to a motor 24 and a pulley 28 attached to the atmosphere side of the support shaft 14 by a timing belt 32,
By this motor 24, the arm shaft 40 is rotationally driven in both forward and reverse directions to swing and rotate the arm 46 as shown by an arrow B so that the holder 8 is mechanically scanned in the Y direction substantially orthogonal to the X direction. ing.

A vacuum seal bearing 52 is attached to the tip of the arm 46 to rotatably support the holder shaft 54 and the holder 8. A holder 8 for holding the wafer 4 is attached to the tip portion thereof at a substantially right angle.

A pulley 50 is attached to the holder shaft 54. An intermediate shaft 42 is rotatably passed through the center of the arm shaft 40, and pulleys 34 and 44 are attached to both ends thereof. The pulleys 44 and 50 have the same diameter and are connected to each other by a timing belt 48.

A timing belt 30 connects a motor 22, a pulley 26, and a pulley 34, which are mounted on the atmosphere side of the support shaft 14, with the motor 22 to move the holder 8 to the arrow C, for example.
It can be rotated in stages like. However, rotation during injection is not performed. In that case, even if the arm shaft 40 rotates as shown by arrow B, the intermediate shaft 42
Does not rotate with arm axis 40.

The posture of the holder 8 during scanning will be described. At that time, as described above, the intermediate shaft 42 and the pulley 44 are in a stopped state.
In this state, when the arm 46 is rotated by θ ° in the clockwise direction as shown in FIG. 8 by the motor 24, the pulley 44 is rotated in the counterclockwise direction by θ ° when viewed from the arm 46 side, and the timing 48 The pulley 50, which has the same diameter as the pulley 44 connected by, rotates by θ ° counterclockwise when viewed from the arm 46 side. Therefore, the holder 8 is scanned so as to draw an arc in the Y direction with the length of the arm 46 as a radius, but the absolute rotation angle is 0 ° and its posture is unchanged. Therefore, the attitude of the wafer 4 mounted on the holder 8 is also constant.

Since the above-mentioned ion implantation apparatus basically also swings and rotates the arm 46 to mechanically scan the wafer 4,
The same effect as in the case of the ion implantation apparatus of this embodiment can be obtained with respect to the conventional example of FIG.
Since 10 is a timing belt drive, it can be said that its structure is complicated.

On the other hand, in the ion implanter of this embodiment, the holder drive unit 120 employs a direct drive motor to directly drive a required portion, so that the timing belt as in the above-described prior example is used. The structure of the holder driving device 120 is greatly simplified as compared with the case of using a pulley, a gear, or the like for that purpose.

〔The invention's effect〕

As described above, according to the present invention, the arm supporting the holder for holding the wafer is reciprocally swung within a predetermined angle range,
As a result, the wafer is scanned with the ion beam X
Since it has a holder drive that mechanically scans in the Y direction, which is substantially perpendicular to the direction, the expensive dynamic vacuum sealing schemes previously attempted are eliminated and, as a result, especially for the injection chamber. It is not necessary to increase the capacity of the vacuum pump, and an ion implanter of this kind can be economically constructed. In addition, the following effects can be achieved.

Since the arm is reciprocally swung within a predetermined angle range in a plane substantially orthogonal to the axis about which the arm takes a posture substantially parallel to the traveling direction of the ion beam, the holder supported by the arm and the holder held by the holder are supported. The wafer is also mechanically scanned in a plane substantially orthogonal to the traveling direction of the ion beam. Therefore, the wafer does not move back and forth in the traveling direction of the ion beam due to its mechanical scanning. The ion beam generally has a larger beam size due to the progress of the heme due to the space electrification effect, so that if the wafer moves back and forth in the beam traveling direction during the mechanical scanning, the beam size in the wafer plane will change. Change, which causes the uniformity of the dose in the wafer surface to deteriorate. On the other hand, in the present invention, as described above, since the wafer does not move back and forth in the beam traveling direction during the mechanical scanning,
It is possible to prevent the uniformity of the dose amount in the wafer surface from being deteriorated without being affected by the change in beam size due to the progress of the beam.

By reciprocally rotating the arm within a predetermined angle range in a plane substantially orthogonal to the beam traveling direction,
Since the holder is mechanically scanned, the space for the mechanical scanning of the holder in the beam traveling direction is small, and therefore the length of the ion implantation apparatus in the beam traveling direction can be shortened.

Even if the diameter of the wafer is increased, the angle range for reciprocating the arm is enlarged for mechanical scanning.
Alternatively, it is possible to easily deal with the problem by increasing the length of the arm, etc., so that it is possible to easily cope with the increase in the diameter of the wafer.

Moreover, in the present invention, since the holder drive unit is directly driven by the direct drive motor, the arm and further the other parts are directly driven. Therefore, the structure of the holder drive unit and the entire ion implantation apparatus can be improved. The structure of can be greatly simplified.

Also, if the second direct drive motor is attached to the arm and the holder is attached at the time of its output, the attitude of the wafer during mechanical scanning can be controlled to be constant, which allows the dose amount and the implantation depth within the wafer surface to be controlled. It is possible to further improve the uniformity of the injection of the seaweed and the like. Also,
Step rotation injection can also be performed by rotating the holder stepwise by the second direct drive motor.

Further, a bearing having a vacuum sealing function is provided on the side wall of the injection chamber, the main shaft is penetrated through this, the third direct drive motor is coupled to the outside of the injection chamber of the main shaft, and the end of the moving main shaft inside the injection chamber is connected. If a direct drive motor for swinging and rotating the arm is attached to the, the angle of the arm and the holder with respect to the ion beam can be changed by the third direct drive motor to change the implantation angle with respect to the wafer.

Further, if the ion beam is made into a parallel beam, the incident angle of the ion beam at each point on the wafer can be made constant, whereby the uniformity of implantation within the wafer surface can be further improved.

Further, by providing two holders and two holder driving devices, it is possible to alternately perform ion implantation and wafer handling in each holder of the two holder driving devices, and the loss time of ion implantation and handling is almost eliminated. Is improved. Since each arm and holder move in an arc shape, both holder driving devices can be arranged close to each other while avoiding mechanical interference with each other, and therefore the ion implantation device can be miniaturized. . Wafers can be handled for both holders under the same conditions.
The effect that the handling of the wafer becomes easy is obtained.

[Brief description of drawings]

FIG. 1 is a horizontal sectional view showing a main part of an ion implantation apparatus according to an embodiment of the present invention. FIG. 2 is a schematic plan view showing an example of an ion beam electrical scanning means. FIG. 3 is a diagram for explaining the attitude of the holder during scanning by the holder driving device in FIG. 4 and 5 are both sectional views taken along the line I-I of FIG. 1, but in different operating states. FIG. 6 is a perspective view showing the wafer transfer device in FIG. FIG. 7 is a horizontal sectional view showing a main part of an example of an ion implantation apparatus which constitutes the preceding example of the present invention. FIG. 8 is a diagram for explaining the posture of the holder during scanning by the holder driving device in FIG. 7. FIG. 9 is a perspective view showing a main part of a conventional ion implanter. 2 ... in-on-beam, 4 ... wafer, 6 ... injection chamber, 8 ... holder, 120 ... holder drive device, 122 ... vacuum seal bearing, 124 ... main shaft, 126 ... third direct drive motor , 132 …… first direct drive motor, 136 …… arm, 138 …… second direct drive motor.

Claims (5)

[Claims] 1. An implantation chamber in which an ion beam electrically scanned in the X direction is guided, a holder for holding a wafer in the implantation chamber, and an arm for supporting the holder. Inject the holder by reciprocally rotating within a predetermined angle range in a plane that is substantially orthogonal to the axis that is apart from the center of the ion beam and that is substantially parallel to the ion beam traveling direction. Y that is substantially orthogonal to the X direction when facing the ion beam indoors
And a holder driving device that mechanically reciprocally scans in a direction,
Further, this holder driving device is provided with a reversible direct drive motor provided in the injection chamber and having the arm attached to its output shaft, as a drive source for reciprocally rotating the arm as described above. Ion implantation equipment. 2. An implantation chamber in which an ion beam electrically scanned in the X direction is guided, a holder for holding a wafer in the implantation chamber, and X in a state where the holder is directed to the ion beam in the implantation chamber. A holder drive device that mechanically reciprocally scans in a Y direction substantially orthogonal to the direction, and the holder drive device is provided in the injection chamber and an arm that supports the holder, and the arm is provided in a predetermined angle range. And a second reversible direct drive motor attached to the arm, and an output shaft of the second direct drive motor. An ion implanter in which the holder is attached to. 3. An implantation chamber in which an ion beam electrically scanned in the X direction is guided, a holder for holding a wafer in the implantation chamber, and X in a state where the holder is directed to the ion beam in the implantation chamber. A holder drive device that mechanically reciprocally scans in a Y direction substantially orthogonal to the direction, and the holder drive device is provided in the injection chamber and an arm that supports the holder, and the arm is provided in a predetermined angle range. A first reversible direct drive motor that reciprocates in a chamber, a bearing having a vacuum sealing function provided on the side wall of the injection chamber, a main shaft that penetrates the bearing, and a single part outside the injection chamber of the main shaft. Is equipped with a third direct drive motor having an output shaft coupled thereto, and the first direct drive motor is attached to the end of the main shaft on the inside of the injection chamber. Ion implantation apparatus. 4. The ion implanter according to claim 1, 2 or 3, wherein the ion beam is one that is electrically scanned in the X direction and is made into a parallel beam. 5. A second holder for holding a wafer in the implantation chamber, and mechanical reciprocating scanning in the Y direction substantially orthogonal to the X direction with the holder facing the ion beam in the implantation chamber. 5. The ion implantation apparatus according to claim 1, further comprising a second holder driving device having the same structure as the holder driving device.