JPH087824A - Ion implanting device and manufacture of semiconductor device, and ion beam control method - Google Patents

Abstract

PURPOSE:To reduce the time necessary for repairing, by repairing a trouble after the temperature of a charge converting means is reduced, reversing the direction of the magnetic field between the magnetic poles of an analyzer magnet, and detecting the condition of positive ions. CONSTITUTION:The analyzer magnet 16 of an ion implanting device 10 is used in a specific condition, a positive ion generated in an ion source 12 is converted to a negative ion by a magnesium cell 14, and the mass spectrometry of the negative ion is carried out by the magnet 16. And only specific negative ions are delivered to an accelerating tube 18, they are accelerated there, and then injected to a tandem accelerator 20. Since the tandem accelerator 20 reaccelerates them while converting the negative ions to the positive ions, the implanting device 10 is suitable to implant the ions at a high energy. And when the device 10 is used at a low energy condition, the magnet 16 is converted, and the polarity of the power source of the accelerating tube 18 is reversed. And the positive ions are flown from the ion source 12 while the cell 14 and the accelerator 20 are being stopped. Consequently, the ions can be implanted continuously without picking up a wafer from a vacuum container.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ion implanter used in a semiconductor manufacturing process or the like, and more particularly to an ion which can be ion-implanted at high energy using a tandem accelerator which requires ion beam charge conversion. Regarding injection device. The present invention also relates to a semiconductor device manufacturing method and an ion beam control method using an ion implantation apparatus.

[0002]

2. Description of the Related Art In the ion implantation technique, for example, an element such as boron (B), phosphorus (P) or arsenic (As) is added to a silicon wafer in order to print a circuit on a wafer and manufacture an LSI into a logic IC or the like. Is essential as a method of introducing. Ion implantation is a process of introducing other impurity elements,
For example, it is superior in controllability of the implantation amount (dose amount) and implantation depth as compared with the vapor phase diffusion method and the solid diffusion method, and is one of the effective means in the manufacture of semiconductor devices.

In the ion implantation apparatus, after the ions generated in a solid or gas ion source are made into plasma, mass analysis is performed by the magnetic field of the ions to accelerate the ions and implant them into the wafer. Therefore, the ion implantation apparatus includes an ion source, an analyzer magnet, and an accelerating means. Further, in addition to the above elements, there is an ion implanter equipped with a magnesium cell and a tandem accelerator, and this ion implanter is suitable for implanting ions with high energy. In this case, the positive ions extracted from the ion source are converted into negative ions in the magnesium cell heated to about 400 ° C. The ions are then mass separated by the analyzer magnet and injected into the tandem accelerator. Negative ions are charged again by N ₂ in the electron stripper in the tandem accelerator, and become single-charge, double-charge, and triple-charge positive ions. The positive ions are then valence-separated by an energy filter and implanted into the wafer.

[0004]

SUMMARY OF THE INVENTION Magnesium cells are
It usually takes 30 to 40 minutes to warm up, and it usually takes 40 to 60 minutes to cool to normal temperature when the apparatus is stopped. Therefore, for example, when the power supply system of the ion implantation apparatus fails, it takes a considerable time from the stop of the apparatus to the start-up. In such a case, it is necessary to perform steps such as repairing the defective portion, generating an ion beam, and observing the beam waveform by Faraday. When shutting down, it is necessary to wait the above-mentioned time until the magnesium cell is completely cooled. Then, it is necessary to wait the above-mentioned time until the magnesium cell is warmed up in order to start up the apparatus after repairing the defective portion. In addition, if there are various failure points,
Whether or not the faulty part has been completely repaired must be diagnosed by generating an ion beam and observing the beam waveform with Faraday. If the defective part is not completely repaired, the device must be stopped and the defective part must be repaired after waiting the above-mentioned time until the magnesium cell is completely cooled again. As described above, when repairing the device, it is necessary to go through processes such as temperature drop of magnesium cell, repair, temperature rise of magnesium cell, ion beam extraction, diagnosis, temperature drop of magnesium cell again, repair, etc. The time required for repair was extremely high.

An ion implanter using a tandem accelerator has an energy range of 200 keV to 3000.
It was suitable for ion implantation at high energy of keV, and ion implantation at lower energy could not be performed. An object of the present invention is to manufacture an ion implanter and a semiconductor device which can shorten the time required for repair when a failure occurs, and can perform ion implantation with high energy and ion implantation with low energy. Is to provide a method.

[0006]

An ion implantation apparatus according to the present invention comprises an ion source 12, charge conversion means 14 for converting positive ions generated in the ion source into negative ions, and ions passing through the charge conversion means. An analyzer magnet 16 for selecting the mass of the analyzer magnet, a means 34 capable of reversing the direction of the magnetic field between the magnetic poles 26 and 28 of the analyzer magnet, an accelerating tube 18 for accelerating the ions emitted from the analyzer magnet, and the acceleration. And a tandem accelerator 20 arranged on the downstream side of the pipe.

[0007]

In the above construction, means for reversing the direction of the magnetic field between the magnetic poles of the analyzer magnet is provided. Therefore, for example, in the case of a failure of the apparatus, the failure of the charge conversion means is waited for and the repair of the failure is carried out. Then, the direction of the magnetic field between the magnetic poles of the analyzer magnet is reversed. Therefore, by generating positive ions from the ion source and passing the positive ions through the analyzer magnet to the accelerating means without increasing the temperature of the charge conversion means, and inspecting the state of these positive ions, the failure repair is completely completed. Diagnose if done. When the trouble is completely repaired, the temperature rise of the charge conversion means is stopped and the semiconductor can be manufactured immediately.

Further, during the operation of the apparatus, a high energy implantation process using a tandem accelerator and a low energy implantation process not using a tandem accelerator are selected by controlling the direction of the current of the analyzer magnet. be able to. In this case, the high energy implantation process using the tandem accelerator and the low energy implantation process not using the tandem accelerator can be continuously performed without taking the wafer out of the vacuum container.

Further, according to the ion beam control method of the present invention, in the analyzer magnet for analyzing the mass of the ions generated in the ion source, the direction of the magnetic field between the magnetic poles of the analyzer magnet is reversed to allow the negative ions and the positive ions. It is characterized by analyzing the mass of any of the above. This allows the ion implanter to be used in various ways.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 4 shows an ion implanter 10 according to an embodiment of the present invention.
FIG. The ion implanter 10 includes an ion source 12
And a magnesium cell 14 as a charge conversion means for converting positive ions generated in the ion source into negative ions, an analyzer magnet 16 for selecting the mass of the ions passing through the magnesium cell 14, and the analyzer magnet 16. An accelerating tube 18 for accelerating ions and a tandem accelerator 20 arranged downstream of the accelerating tube 18 are provided. A beam filter 22 is arranged on the downstream side of the tandem accelerator 20, and the ion beam is injected toward a wafer mounted on a disk 24.

As shown in FIG. 1, the analyzer magnet 16 has magnetic poles 26 and 28 and coils (not shown) wound around the magnetic poles 26 and 28, and the ion implanter 10
Is also the magnetic poles 26, 28 of the analyzer magnet 16.
And means for reversing the direction of the magnetic field between.
The magnetic pole reversing means is composed of a changeover switch 34 arranged in the middle of cables 32 and 33 connecting the analyzer magnet 16 and the power supply 30 for the analyzer magnet, and the changeover switch 34 reverses the direction of the current flowing through the analyzer magnet 16. Can be made. Although cables 32 and 33 are shown in FIG. 1 as being connected to magnetic poles 26 and 28, these cables 32 and 33 are connected to each terminal of the coil.

In FIG. 2, the magnetic pole 26 becomes the S pole,
The direction of the current is controlled so that the magnetic pole 28 becomes the N pole. In this case, negative ion mass spectrometry can be performed. In FIG. 3, the direction of the current is controlled so that the magnetic pole 26 becomes the N pole and the magnetic pole 28 becomes the S pole. In this case, positive ion mass spectrometry can be performed.

The ion implantation apparatus 10 includes an operation panel (not shown), and the changeover switch 34 is adapted to be changed over by a control signal from the operation panel. Therefore, the changeover switch 34 is automatically operated in connection with the operation of other members. On the other hand, the changeover switch 34 can be manually changed over.

In the ion implanter 10 of FIG. 4, the analyzer magnet 16 is normally used in the state of FIG.
Therefore, positive ions generated in the ion source 12 are converted into negative ions in the magnesium cell 14, mass analysis of the negative ions is performed in the analyzer magnet 16, and only predetermined negative ions are sent to the accelerating tube 18. The negative ions are accelerated by the accelerating tube 18 and enter the tandem accelerator 20. Tandem accelerator 2
0 re-accelerates ions while converting negative ions into positive ions. Therefore, the ion implantation apparatus 10 is suitable for implanting ions with high energy.

The ion implanter 10 is suitable for being used at a high energy of 200 keV to 3000 keV. Here, the ion implantation apparatus 10 is set to 200 k
If there is a request to use at low energy in the range of eV or less, the analyzer magnet 16 is switched to the state of FIG. 3, the polarity of the power source of the acceleration tube 18 is reversed, and the magnesium cell 14 and the tandem accelerator 20 are stopped. , Fly positive ions from the ion source 12. Therefore, it is necessary that the accelerating tube 18 also be capable of reversing the polarity of the power source.

This state is shown in FIG. The ion implantation apparatus 10 in this state includes the ion source 12, the analyzer magnet 16, the acceleration tube 18, and the beam filter 22.
And is equivalent to an ion implanter used in the conventional medium and low energy. Thus, the high energy implantation process using the tandem accelerator 20 and the low energy implantation process not using the tandem accelerator 20 can be continuously performed without taking the wafer out of the vacuum container.

A high energy implantation process using the tandem accelerator 20 and a low energy implantation process not using the tandem accelerator 20 can be performed continuously without taking the wafer out of the vacuum chamber. Is carried out in the manufacture of. Conventionally, when a channel cut and a channel dose are continuously performed after a well implant in a CMOS, the well and the channel cut are implanted by a high energy ion implanter and a channel dose medium current ion implanter. Was there. However, according to the invention,
It is possible to carry out continuous injection without carrying out wasteful wafer transfer and without taking out the wafer from the vacuum container. Therefore, the amount of dust adhering during wafer transfer is reduced.

When the ion implantation apparatus 10 fails during normal use, the apparatus is turned off and the failure is repaired. At this time, it takes 40 to 60 minutes for the temperature of the magnesium cell 14 to decrease, as described above. When the temperature of the magnesium cell 14 decreases, the failure is repaired and a diagnosis is made as to whether or not the device is normal. Therefore, the analyzer magnet 16 is changed from the state of FIG. 2 to the state of FIG. 3, the polarity of the power source of the acceleration tube 18 is reversed, the magnesium cell 14 and the tandem accelerator 20 are stopped, and the ion source 12, the analyzer magnet 16 and the acceleration are accelerated. The tube 18 is used to fly the positive ions.

Therefore, while observing the waveform of the beam using Faraday, it is diagnosed whether or not the failure point has been completely repaired. If it is determined that the defective portion has been completely repaired, the temperature of the magnesium cell 14 is raised and the ion implantation apparatus 10 is ready for use. If it is determined that the faulty part is not completely repaired, stop the ion source 12, the analyzer magnet 16 and the acceleration tube 18,
Make further repairs. Therefore, when the repair is completed, the diagnosis is performed again by the above procedure. If it is determined that the defective portion has been completely repaired, the temperature of the magnesium cell 14 is raised and the ion implantation apparatus 10 is ready for use. As a result, it is not necessary at least to repeatedly increase and decrease the temperature of the magnesium cell 14, and the time required for repair can be shortened.

[0020]

As described above, according to the present invention,
The time required for repair when a failure occurs can be shortened, and high-performance ion implantation equipment capable of performing high-energy ion implantation and low-energy ion implantation, and the cost of a semiconductor device There is provided a method for manufacturing a semiconductor device capable of reducing the noise.

[Brief description of drawings]

FIG. 1 is a diagram showing an analyzer magnet and a changeover switch according to an embodiment of the present invention.

FIG. 2 is a diagram showing one state of the analyzer magnet of FIG.

FIG. 3 is a diagram showing another state of the analyzer magnet of FIG.

FIG. 4 is a diagram showing an ion implantation apparatus according to an embodiment of the present invention.

5 is a view of the ion implanter in another state of FIG.

[Explanation of symbols]

 12 ... Ion source 14 ... Magnesium cell 16 ... Analyzer magnet 18 ... Accelerator tube 20 ... Tandem accelerator tube 26, 28 ... Magnetic pole 34 ... Changeover switch

Claims (8)

[Claims] 1. An ion source (12) and charge conversion means (1) for converting positive ions generated in the ion source into negative ions.
4), an analyzer magnet (16) for selecting the mass of ions that have passed through the charge conversion means, and means (34) for reversing the direction of the magnetic field between the magnetic poles (26, 28) of the analyzer magnet. And an accelerating tube (18) that accelerates the ions emitted from the analyzer magnet,
Tandem accelerator (20) arranged downstream of the acceleration tube
And an ion implantation device. 2. The ion implantation apparatus according to claim 1, further comprising a changeover switch for reversing a direction of a current flowing through the analyzer magnet, provided in the middle of a cable connecting the analyzer magnet and the power source for the analyzer magnet. . 3. The ion implanter according to claim 2, wherein the changeover switch is adapted to be changed over by a control signal from an ion implanter operation panel. 4. The ion implantation apparatus according to claim 2, wherein the changeover switch is manually changed over. 5. The ion implantation apparatus according to claim 1, wherein a high energy implantation process using a tandem accelerator and a low energy implantation process not using a tandem accelerator are performed to control a current direction of an analyzer magnet. A method for manufacturing a semiconductor device, characterized in that the semiconductor device is selected by: 6. A high-energy implantation process using a tandem accelerator and a low-energy implantation process not using a tandem accelerator are continuously performed without ejecting a wafer from a vacuum container. The method for manufacturing a semiconductor device according to claim 5. 7. The method of manufacturing a semiconductor device according to claim 1, wherein the failure diagnosis is performed without raising the temperature of the charge conversion means. 8. An analyzer magnet for selecting the mass of ions generated by an ion source, wherein the mass of either negative ions or positive ions is analyzed by reversing the direction of the magnetic field between the magnetic poles of the analyzer magnet. Ion beam control method characterized by the above.