JP2674356B2 - Ion implanter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called hybrid scan type ion implanter for electrically scanning an ion beam and mechanically scanning a target in a direction substantially orthogonal thereto.

[0002]

2. Description of the Related Art A conventional example of this type of ion implantation apparatus is shown in FIG.
Shown in

This ion implantation apparatus is of a so-called parallel scan system, and a spot-shaped ion beam 2 extracted from an ion source (not shown) and subjected to mass analysis, acceleration, etc. as necessary is used as a scanning power source. By the cooperation of the two sets of scanning electrodes 4 and 6 to which scanning voltages (triangular wave-shaped voltages) having phases different from each other by 180 degrees are applied from 8,
That is, by deflecting the ion beam 2 deflected on one side in the opposite direction by the same angle on the other side, electrostatic parallel scanning is performed in parallel in the X direction (for example, horizontal direction; hereinafter the same), and a wide ion beam (parallel beam) is obtained. I'm trying to make 2.
In this example, the scanning electrodes 4 and 6 and the scanning power source 8 constitute a scanning means for the ion beam 2.

A deflection power source 12 is provided between the scanning electrodes 4 and 6.
Is provided with a set of deflection electrodes 10 to which a DC deflection voltage is applied.
A neutral beam traveling straight is separated by deflecting it by a predetermined angle θ (for example, about 7 degrees) in a Y direction (for example, a vertical direction; the same applies hereinafter) that is substantially orthogonal to the direction. In this example, the deflection electrode 10 and the deflection power source 12 form a deflection means for the ion beam 2.

Further, a holder 16 for holding a target (for example, a wafer) 14 is arranged on the downstream side of the scanning electrode 6, and these are mechanically moved in the Y direction in the irradiation region of the ion beam 2 by a target driving device 18. The scanning is performed, and the ion beam 2 is scanned in cooperation with the scanning in the X direction to uniformly implant ions on the entire surface of the target 14.

Further, in this example, multipoint beam monitors 20 and 22 are provided on the upstream side and the downstream side of the target 14. Each of the multi-point beam monitors 20 and 22 has a plurality of Faraday cups having the same area, which measure the beam current of the ion beam 2, arranged in the X direction. Current I
Are taken into the control device 26. The multi-point beam monitors 20 and 22 are provided such that the controller 26 measures the uniformity of the ion beam 2 and the parallelism of the ion beam 2 based on the measurement data of the beam current I of the ion beam 2 by them. This is so that the measurement, and further, the waveform shaping of the scanning voltage output from the scanning power supply 8 can be performed.

Of these, the multipoint beam monitor 22 on the downstream side
Is fixed on the beam orbit for ion implantation into the target 14, but the target drive unit 18 can remove the target 14 and the holder 16 from the plane of the beam orbit during measurement by the beam.

The multi-point beam monitor 20 on the upstream side is attached to a monitor driving device 24. This allows the multi-point beam monitor 20 to be placed on the beam orbit during measurement by the multi-point beam monitor 20 and during ion implantation into the target 14. Alternatively, it can be removed from the beam trajectory during measurement by the multipoint beam monitor 22 on the downstream side. The monitor driving device 24 is controlled by the control device 26.

[0009]

However, in the above-mentioned ion implantation apparatus, since the upstream multipoint beam monitor 20 is mechanically moved by the monitor driving device 24, at least the multipoint beam monitor 20 is moved. It takes about several seconds, which causes a problem that the ion beam 2 cannot be measured at high speed.

Further, the multi-point beam monitor 20 (and 2
In 2), mechanically delicate parts such as carbon for receiving the ion beam 2 and ceramics for insulating and supporting the ion beam 2 are usually used. Therefore, by moving the multipoint beam monitor 20, Providing mechanical vibration is not preferable in terms of reliability.

Therefore, according to the present invention, the ion beam can be measured at high speed by the above-mentioned upstream and downstream multi-point beam monitors, and the reliability of the multi-point beam monitor can be improved. The main object of the present invention is to provide an ion implantation device having such a structure.

[0012]

In order to achieve the above object, in the ion implantation apparatus of the present invention, the multipoint beam monitor on the downstream side is fixed on the beam orbit for ion implantation to the target, and the upstream side is fixed. The multi-point beam monitor on the side is fixed at a position deviating from the beam trajectory for implanting ions to the target, and the deflection means is controlled to control the ion beam trajectory to the trajectory for implanting ions to the target. It is characterized in that a control device having a function of switching to an orbit entering the multipoint beam monitor on the upstream side is provided.

[0013]

According to the above construction, the trajectory of the ion beam is switched by the control device and the deflecting means in a state where the target is removed from the beam trajectory for ion implantation by the driving device, so that the ion beam is moved to the upstream side. The multi-point beam monitor and the multi-point beam monitor on the downstream side can be instantaneously switched and made incident. Therefore, the ion beam can be measured at high speed by both multi-point beam monitors.

[0014]

1 is a view partially showing an ion implantation apparatus according to an embodiment of the present invention, and FIG. 2 is a view showing a beam line in the apparatus of FIG. 1 as seen from the side. Parts that are the same as or correspond to those in the conventional example of FIG. 3 are denoted by the same reference numerals, and differences from the conventional example will be mainly described below.

In this embodiment, the above-mentioned multipoint beam monitor 22 on the downstream side is similar to the conventional example in that the target 1
4 is fixed on the beam orbit for ion implantation, and the multipoint beam monitor 20 on the upstream side is the target 14
Is fixed at a position deviated upward from the beam trajectory for ion implantation. Therefore, the monitor driving device 24 as in the conventional example is not necessary.

Further, the deflection power source 12 is controlled by the control device 26a corresponding to the control device 26 described above and the deflection voltage output from the deflection power supply 12 is switched, so that the trajectory of the ion beam 2 is ion-implanted into the target 14. trajectory performed is to have a so and switching function (deflection angle theta ₁ in FIG. 2) trajectories entering the upstream side of the multipoint beam monitor 20 (deflection angle theta ₂ in FIG. 2).

When ion implantation is performed on the target 14, the deflection angle of the ion beam 2 is set to θ ₂ (of course, the ion beams 2 are scanned by the scanning electrodes 4 and 6).
(While scanning in the X direction), the target 14 may be scanned in the Y direction by the target drive device 18. At this time, the upstream multi-point beam monitor 20 does not get in the way.

When the ion beam 2 is measured by the multi-point beam monitors 20 and 22 at two locations, upstream and downstream, the target 14 and the holder 16 are connected to the target drive unit 18.
When the ion beam 2 is deviated from the beam trajectory for ion implantation by the control device 26a, the deflection power source 12 is controlled to switch the trajectory of the ion beam 2 between the deflection angles θ ₁ and θ ₂ as described above. Can be instantly switched (for example, in about several tens of milliseconds) to be incident on the upstream multipoint beam monitor 20 and the downstream multipoint beam monitor 22.

Therefore, the ion beam 2 can be measured at high speed by the two-point beam monitors 20 and 22.
As a result, for example, such measurement is performed while the target 14 on the holder 16 is exchanged between the implanted target and the unimplanted target 14 to measure the ion beam 2 each time the target 14 is ion-implanted. It is also possible to perform the above (for example, the uniformity measurement, the parallelism measurement, and the scanning voltage waveform shaping as described above) without deteriorating the throughput of the ion implantation apparatus.

Moreover, since the two multi-point beam monitors 20 and 22 are fixed and have no mechanical operation, no vibration is applied to them, and therefore their reliability is also improved.

Further, since the monitor driving device 24 provided in the conventional example is unnecessary, the cost is reduced. By the way, the configuration of the control device 26a is not so different from the conventional example because the control device for the monitor drive device 24 is required even in the conventional control device 26.

Unlike the above example, the multipoint beam monitor 20 on the upstream side may be provided further below the beam trajectory for ion implantation into the target 14 (that is, on the larger deflection angle side). .

Also, two multi-point beam monitors 20, 22 are provided.
Need only have a relationship between the upstream side and the downstream side of the ion beam 2, and therefore the target 14 is set to the multipoint beam monitor 2
It may be arranged on the upstream side of 0.

The deflection electrode 10 may be provided at the upstream side of the scanning electrode 4 or the downstream side of the scanning electrode 6.

When the parallel beam is not required, the scanning electrode 6 on the downstream side is unnecessary.

The above-described scanning and deflection of the ion beam 2 may be performed by using a magnetic field, unlike the above example.

Further, in this specification, the X direction and the Y direction
The directions only represent two orthogonal directions, and therefore, for example, the X direction may be viewed as a horizontal direction, a vertical direction, or a direction inclined from them.

[0028]

As described above, according to the present invention, since the ion beam can be instantaneously switched and made incident on the upstream multipoint beam monitor and the downstream multipoint beam monitor, both multipoint beams can be incident. The ion beam can be measured at high speed by the monitor. Moreover, since both multi-point beam monitors are fixed and have no mechanical operation, their reliability is also improved.

[Brief description of the drawings]

FIG. 1 is a diagram partially showing an ion implantation device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a beam line in the apparatus of FIG. 1 as viewed from the side.

FIG. 3 is a diagram partially showing an example of a conventional ion implantation apparatus.

[Explanation of symbols]

 2 ion beam 4,6 scanning electrode 8 scanning power supply 10 deflection electrode 12 deflection power supply 14 target 16 holder 18 target drive device 20,22 multi-point beam monitor 26a control device

Claims (1)

(57) [Claims] 1. A scanning unit for electrically scanning an ion beam in the X direction, a deflecting unit for electrically deflecting the ion beam in a Y direction substantially orthogonal to the X direction, and a target in the Y direction. Two multi-point beam monitors each having a mechanical scanning drive device and a plurality of Faraday cups having the same area and arranged in the X direction for measuring the beam current of the ion beam. In the ion implantation apparatus provided with a side and a downstream side, the multipoint beam monitor on the downstream side is fixed on the beam orbit for ion implantation to the target, and the multipoint on the upstream side is fixed. The beam monitor is fixed at a position deviating from the beam trajectory for ion implantation to the target, and the deflection means is controlled to control the ion beam trajectory. An ion implantation apparatus comprising a controller having a function of switching between an orbit for performing ion implantation and a trajectory for incidence on the upstream multipoint beam monitor.