JPH0696716A - Ion implanting device - Google Patents

Abstract

PURPOSE:To obtain an ion implanting device which can easily remove scattered resist which is scattered and stuck on a beam passing apparatus at the time of ion implantation. CONSTITUTION:A gas generating means 21 capable of introducing reactive gas G for light ashing into the wafer opposing surface side of beam passing apparatuses 3, 4, 5, 6 through which an ion beam passes between an analyzing magnet 2 and immediately before a wafer 8 is provided. Also, an ultraviolet ray generating means 22 capable of radiating ultraviolet rays to the reactive gas G introduced into the beam passing apparatuses 3, 4, 5, 6 is provided. The reactive gas G brought into the excited state with radiation of ultraviolet rays is brought into reaction to a scattered resist stuck to the wafer opposing surface side of the beam passing apparatuses 3, 4, 5, 6 to easily remove it.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ion implantation apparatus for irradiating a wafer for semiconductor production with an ion beam to introduce impurities.

[0002]

2. Description of the Related Art FIG. 5 is a diagram showing the equipment structure of a conventional ion implantation apparatus used in semiconductor manufacturing.
1 is an ion source, 2 is an analysis magnet for extracting only desired ions from the ions from the ion source 1, 3 is an analysis slit,
4 is the first suppressor electrode, 5 is the Faraday box, 6 is the second
A suppressor electrode, 7 is an ion beam showing a flow of ions, 8 is a silicon wafer for semiconductor production, and a resist (photoresist) for performing ion implantation only on a necessary portion of the wafer 8 is applied on the upper surface thereof, if necessary. Has been done. Reference numeral 9 denotes a disk for positioning and fixing a plurality of wafers 8 on the upper surface thereof and rotating at a high speed, and performing translational movement in the direction of the arrow to irradiate the ion beam 7 on the entire surface of the wafer 8 at the time of ion implantation into the wafer 8. The scattered resist is scattered and adhered to the inner surface of the Faraday box 5 or the like.

Next, the operation of this ion implanter will be described. A plasma containing desired ions is created by the ion source 1, and only positive ions are extracted in an electric field and introduced into the analysis magnet 2. Then, utilizing the fact that the ions have different radii of gyration in the magnetic field depending on their masses, only the desired ions are extracted from the introduced positive ions by mass analysis in the analysis magnet 2, and this ion is extracted. Further, the unnecessary ions are removed by passing through the analysis slit 3. In this way, the ion beam 7, which finally becomes only the necessary ions, passes through the first suppressor electrode 4, the Faraday box 5, and the second suppressor electrode 6, and the plural ion beams 7 on the disk 9 that rotate and translate. The upper surface of the wafer 8 is uniformly irradiated. Then, a desired amount of desired ions are implanted into the uncoated portion of the wafer 8 and impurities are introduced into this portion to manufacture a semiconductor.

The amount of ions implanted in the wafer 8 is determined by the disk 9 containing the wafer 8, the first suppressor electrode 4,
It is measured as a current value by a Faraday measuring system composed of the Faraday box 5 and the second suppressor electrode 6. The first and second suppressor electrodes 4 and 6 are for preventing electrons from leaking from the Faraday measuring system and causing an injection amount error.

When the upper surface of the wafer 8 is ion-implanted by the ion implantation apparatus, the resist coated on the wafer 8 is also irradiated with the ion beam 7, so that the resist is sputtered and the wafer 8 is sputtered.
An inner surface or an outer surface (hereinafter referred to as a wafer facing surface) of a device (hereinafter, referred to as a beam passing device) through which the ion beam 7 between the analysis magnet 2 and the wafer 8 immediately before the wafer 8 which scatters outward is passed. The phenomenon that it adheres to occurs.

[0006]

However, when the amount of the scattered resist 10 adhered increases, the scattered resist 10 adhered and changed in quality peels off to generate particles, which impairs the function of the apparatus. In addition to the inconvenience, especially when a large amount of the scattered resist 10 adheres to the surface of the Faraday measuring system such as the Faraday box 5 through which the ion beam 7 passes, these form an insulating film and impair the function of the Faraday measuring system. As a result, there is an inconvenience of causing a wafer charge-up.

Therefore, in order to prevent the above inconvenience,
Although the Faraday measurement system and the like must be disassembled and cleaned on a regular basis, there was a problem that this work had to be done manually and was not easy.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an ion implantation apparatus which can easily remove scattered resists scattered and adhered.

[0009]

A first aspect of the present invention is an ion implantation apparatus for irradiating a semiconductor manufacturing wafer with an ion beam to introduce impurities into the wafer.
Gas generating means capable of introducing a reactive gas for optical ashing is provided on the wafer facing surface side of the beam passing device between the analysis magnet and immediately before the wafer, and is introduced to the wafer facing surface side of the beam passing device by the gas generating means. It is to have a scattered resist removing device provided with an ultraviolet ray generating means capable of irradiating the reactive gas with ultraviolet rays.

A second aspect of the present invention is an ion implantation apparatus for irradiating a wafer for semiconductor production with an ion beam to introduce impurities into the wafer. On the surface side, a gas generating means capable of introducing ozone gas or a mixed gas mainly composed of ozone gas, and an ultraviolet ray generating means capable of irradiating the gas introduced from the gas generating means to the wafer facing surface side of the beam passing device with ultraviolet rays are provided. It is to have a scattered resist removing device provided.

A third aspect of the present invention is an ion implantation apparatus for irradiating a wafer for semiconductor production with an ion beam to introduce impurities into the wafer, which is a beam passing device facing the wafer from immediately before the wafer to the analysis magnet. On the surface side, a gas generating means capable of introducing a reactive gas for optical ashing, and an ultraviolet ray generating means capable of irradiating the reactive gas introduced to the wafer facing surface side of the beam passing device with ultraviolet rays by the gas generating means are provided. In addition to having a scattered resist removing device provided, by having a control means that automatically introduces the reactive gas from the scattered resist removing device and irradiates with ultraviolet rays for each introduction process of impurities to a predetermined amount of wafers. is there.

[0012]

When the reactive gas is irradiated with ultraviolet rays, the reactive gas is brought into an excited state and reacts with the resist to cause photo ashing. That is, the resist is decomposed and gasified by the reactive gas in the excited state and removed. Therefore, according to the first aspect of the present invention, the reactive gas is introduced into the wafer facing surface side of the beam passing device of the ion implantation apparatus by the gas generating means, and the reactive gas is irradiated with ultraviolet rays by the ultraviolet ray generating means. During the ion implantation, the scattered resist that is sputtered from the wafer and scattered and adhered to the surface of the beam passing device facing the wafer is removed by reacting with the excited reactive gas.

In a second aspect of the present invention, the reactive gas is ozone gas, and the excited oxygen atoms formed by irradiating the ozone gas with ultraviolet rays react with the scattered resist to face the wafer of the beam passing device. This scattered resist adhering to the surface side is removed. Incidentally, in consideration of the case where the scattered resist has a foreign substance or the case where the scattered resist is denatured, another gas capable of coping with this may be mixed into the ozone gas.

According to the third aspect of the present invention, the control means is provided so that the scattered resist is automatically removed every time the impurity is introduced into a predetermined amount of the wafer. That is, when the introduction process of impurities to a predetermined amount of wafer is completed, the irradiation of the ion beam to the wafer is stopped, and the reactive gas is emitted from the reactive gas generator of the scattered resist removing device to the wafer facing surface side of the beam passing device. After being introduced, ultraviolet rays are emitted from the ultraviolet ray generator to remove the scattered resist attached. Then, if this removing operation is performed for a predetermined time, the introduction of the reactive gas and the irradiation of the ultraviolet ray to the reactive gas are stopped, and the wafer is again irradiated with the ion beam.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. Example 1. FIG. 1 is a diagram showing an embodiment of the ion implanter according to the first and second aspects of the invention. In the figure, the same or corresponding parts as those of the conventional ion implanter shown in FIG. The same reference numerals are given and the description thereof is omitted.

In the figure, 21 is the Faraday box 5 and the second.
An ozone generator as a gas generating means capable of introducing the ozone gas G, which is a reactive gas, to the surface of the beam passing device such as the suppressor electrode 6 facing the wafer, 22 is an ozone generator 21.
A plurality of ultraviolet lamps serving as ultraviolet ray generating means capable of irradiating the ozone gas G, which is attached to the upper part of the ozone gas generator 21 on the wafer facing surface side of the beam passing device, and 23 is the ozone generator 21. And a UV lamp 22, which is a scattered resist removing device. As shown by an arrow A, the scattered resist removing device 23 has an operating position B immediately below the second suppressor electrode 6 and a standby position R to the right thereof. It is possible to move between and. In addition,
As shown by the arrow B, the disk 9 can also be moved to the ion implantation position C and the retracted position D shown in the drawing which is moved slightly leftward from the ion implantation position C.

Next, the operation of the ion implantation apparatus will be described mainly with respect to the operation of the scattered resist removing apparatus 23. In ion implantation to the wafer 8, since a part of the upper surface of the wafer 8 is covered with a resist, this resist scatters to the outside of the wafer 8 at the time of ion implantation to the wafer 8, and the scattered resist 10 is used as a beam passing device. It adheres to the wafer facing surface side, that is, the inner surface of the Faraday box 5 and the lower surface of the second suppressor electrode 6. Then, ion implantation is performed on a predetermined amount of wafers 8, and when the amount of the scattered resist 10 reaches or exceeds a certain allowable amount, the ion implantation of the wafer 8 by the ion implantation apparatus is stopped and the disk 9 is moved to the ion implantation position. From the standby position (b) to the operating position (a) below the second suppressor electrode 6 while moving from the retreat position to the retreat position d.

Then, the ozone gas G is introduced from the ozone generator 21 to the wafer facing surface side of the beam passing device, that is, to the inner surface of the Faraday box 5 and the wafer surface side of the second suppressor electrode 6, and the ultraviolet lamp 22 is turned on. The ozone gas G on the lever is irradiated with ultraviolet rays. As a result, excited oxygen atoms are generated, and the excited oxygen atoms react with the scattered resist 10 attached to the inner surface of the Faraday box 5 or the like, and the scattered resist 10 is decomposed, gasified, and removed. When the removal of the scattered resist 10 is completed, the scattered resist removing device 23 is moved to the standby position B, the disk 9 is moved to the ion implantation position C, and the ion implantation of the wafer 8 by the ion implantation device is performed again. Be started.

At the stage where the predetermined amount of ions have been implanted into the wafer 8 as described above, excited oxygen generated by irradiating the ozone gas G with ultraviolet rays from the scattered resist removing device 23 on the wafer facing surface side of the beam passing device. Atoms are caused to flow and the scattered resist is removed by the excited oxygen atoms. Therefore, as compared with the case where the scattered resist is removed by manually disassembling the Faraday box 5 and the first and first suppressor electrodes 4 and 6. The scattered resist 10 can be easily removed.

The scattered resist 10 may contain impurities such as arsenic implanted into the wafer 8 or may be altered by the heat of the ion beam 7, so that the ozone gas G alone is sufficient. Since it may not be removed in some cases, as the reactive gas, a mixed gas containing ozone gas G as a main component, but adding another gas to ozone gas G to sufficiently deal with the adhered resist 10 is also used.

Here, removing the resist by irradiating a reactive gas such as ozone gas G with ultraviolet rays (light) to promote the reaction between the resist and the reactive gas is performed.
Although generally referred to as optical ashing, it goes without saying that a gas other than ozone gas G capable of optical ashing may be used as the reactive gas.

Example 2. FIG. 2 is a diagram showing another embodiment of the ion implantation apparatus according to the first invention and the second invention of the present invention. The second embodiment relates to a case where the disk 9 and the scattered resist removing device 23 do not have to be moved when removing the scattered resist.

That is, an ozone generator 21 as a gas generating means is arranged in the vicinity of the first suppressor electrode 4, and the ozone gas G from the ozone generator 21 is discharged between the first suppressor electrode 4 and the Faraday box 5. The apparatus is introduced on the wafer facing surface side of these devices, and the ultraviolet lamp 22 serving as an ultraviolet ray generating means is arranged at the lower end of the Faraday box 5 at a position that does not interfere with ion implantation.

Therefore, when the ion implantation of a predetermined amount of wafers 8 is completed, the ozone gas G is immediately introduced from the ozone generator 21 into the Faraday box 5 or the like, and the ultraviolet lamp 22 is turned on to turn on the Faraday box 5 or the like. It is possible to remove the scattered resist 10 attached to the. That is, the scattered resist 10 can be removed in a shorter time than in the case of the first embodiment, and the moving means of the disk 9 and the scattered resist removing device 23 are not required, so that the size and cost of the device can be reduced. it can.

Example 3. FIG. 3 is a diagram showing still another embodiment of the ion implantation apparatus according to the first invention and the second invention of the present invention. In the ion implantation apparatus of this embodiment, the first suppressor electrode 4 which constitutes the Faraday measurement system
The Faraday box 5 is disposed on the rear surface side of the disk 9, and the electron neutralizer 11 is provided as a beam passing device between the analysis slit 3 and the front surface of the disk 9. Although the second suppressor electrode 6 is not provided, the other structure is the same as that of the ion implanter of the first embodiment.

In such an ion implantation apparatus, the scattered resist 10 adheres to the inner surface of the electron neutralizer 11, which is the surface facing the wafer.
Is movably arranged between an operating position (i) immediately below the electron neutralizer 11 and a standby position (b) on the right side thereof. The disk 9 is also movably arranged between the ion implantation position C and the retracted position D, which is a position slightly left to the left in the drawing.

Therefore, this ion implanter can also have the same effect as the ion implanter of the first embodiment.

Example 4. FIG. 4 is a diagram showing an embodiment of the ion implantation apparatus according to the third invention of the present invention. In the ion implanter in this embodiment, a fixed amount of wafers 8
This is the case where the control means 24 is provided so as to automatically operate the scattered resist removing device 23 every time the ion implantation process is performed.

The operation of the control means 24, that is, the programming operation will be described below. When the ion implantation process for a certain amount of wafers 8 is completed, the ion implantation process is automatically stopped, the disk 9 is automatically moved from the ion implantation position C to the retreat position D, and the scattered resist removing device 23 is on standby. Automatically move from position b to operating position a. Next, the ozone gas G is automatically introduced from the ozone generator 21 to the wafer facing surface side of the beam passing device such as the Faraday box 5, and the ultraviolet lamp 22 is automatically turned on. Then, this operation is continued for a fixed time, and after the lapse of a predetermined time for removing the scattered resist 10, the introduction of the ozone gas G and the lighting of the ultraviolet lamp 22 are automatically stopped, and the scattered resist removing device 23 is moved to the standby position b. And the disk to the ion implantation position are automatically performed, and the ion implantation operation is automatically restarted again.

As described above, since the scattered resist is automatically removed by the programming operation by the control means 24, the scattered resist can be removed more reliably than in the case of the first embodiment. Of course, the control means 24 may be provided in the ion implanters of the second and third embodiments.

[0031]

Since the present invention is constituted as described above, it has the following effects.

According to the first aspect of the present invention, in an ion implantation apparatus for irradiating a wafer for semiconductor production with an ion beam to introduce impurities into the wafer, a beam passing device between the analysis magnet and immediately before the wafer is used. Gas generating means capable of introducing a reactive gas for optical ashing to the wafer facing surface side, and ultraviolet ray generating means capable of irradiating the reactive gas introduced to the wafer facing surface side of the beam passing device with ultraviolet rays by the gas generating means. Since there is a scattered resist removing device provided with, the scattered resist removing device can easily remove the scattered resist that is scattered and adhered to the wafer facing surface side of the beam passing device.

According to a second aspect of the present invention, in an ion implantation apparatus for irradiating a wafer for semiconductor production with an ion beam to introduce impurities into the wafer, a beam passing device between the analysis magnet and immediately before the wafer is used. Gas generating means capable of introducing ozone gas or a mixed gas mainly composed of ozone gas to the wafer facing surface side, and ultraviolet ray generating means capable of irradiating the gas introduced from the gas generating means to the wafer facing surface side of the beam passing device with ultraviolet rays. Since there is a scattered resist removing device provided with, the scattered resist removing device can easily remove the scattered resist that is scattered and adhered to the wafer facing surface side of the beam passing device.

According to the third aspect of the present invention, in an ion implantation apparatus for irradiating a wafer for semiconductor production with an ion beam to introduce impurities into the wafer, a beam passing device between the analysis magnet and immediately before the wafer is used. Gas generating means capable of introducing a reactive gas for optical ashing to the wafer facing surface side, and ultraviolet ray generating means capable of irradiating the reactive gas introduced to the wafer facing surface side of the beam passing device with ultraviolet rays by the gas generating means. And a control means for automatically introducing the reactive gas from the scattered resist removing apparatus and irradiating the ultraviolet ray every time the impurity is introduced into a predetermined amount of the wafer. Therefore, the scattering resist removing device and the control means scatter to the surface of the beam passing device facing the wafer. It can be performed to remove the resist easily and reliably.

[Brief description of drawings]

FIG. 1 is a device configuration diagram of an ion implantation apparatus according to a first embodiment of the present invention.

FIG. 2 is a device configuration diagram of an ion implantation device according to a second embodiment of the present invention.

FIG. 3 is a device configuration diagram of an ion implantation apparatus according to a third embodiment of the present invention.

FIG. 4 is a device configuration diagram of an ion implantation device according to a fourth embodiment of the present invention.

FIG. 5 is a device configuration diagram of a conventional ion implantation device.

[Explanation of symbols]

 2 analysis magnet 3 analysis slit (beam passing device) 4 first suppressor electrode (beam passing device) 5 Faraday box (beam passing device) 6 second suppressor electrode (beam passing device) 7 ion beam 8 wafer 10 scattering resist 11 in electron Washer (beam passing device) 21 Ozone generator (gas generating means) 22 Ultraviolet lamp (ultraviolet generating means) 23 Scattered resist removing device 24 Control means G Ozone gas (reactive gas)

Claims (3)

[Claims] 1. An ion implantation apparatus for irradiating a semiconductor manufacturing wafer with an ion beam to introduce impurities into the wafer, wherein an optical beam is applied to a wafer facing surface side of a beam passing device between an analysis magnet and immediately before the wafer. Scattering provided with gas generating means capable of introducing a reactive gas for ashing, and ultraviolet ray generating means capable of irradiating the reactive gas introduced to the wafer facing surface side of the beam passing device with the ultraviolet ray by the gas generating means. An ion implantation apparatus having a resist removing apparatus. 2. An ion implantation apparatus for irradiating a semiconductor manufacturing wafer with an ion beam to introduce impurities into the wafer, wherein an ozone gas is provided on a surface of the beam passing device facing the wafer between the analysis magnet and the wafer immediately before the wafer. Alternatively, a gas generating means capable of introducing a mixed gas mainly composed of ozone gas, and an ultraviolet ray generating means capable of irradiating the gas introduced from the gas generating means to the wafer facing surface side of the beam passing device with ultraviolet rays are provided. An ion implantation apparatus having a scattered resist removing apparatus. 3. An ion implanter for irradiating a wafer for semiconductor production with an ion beam to introduce impurities into the wafer, wherein an optical beam is applied to a wafer facing surface side of a beam passing device from an analysis magnet to immediately before the wafer. Scattering provided with gas generating means capable of introducing a reactive gas for ashing, and ultraviolet ray generating means capable of irradiating the reactive gas introduced to the wafer facing surface side of the beam passing device with the ultraviolet ray by the gas generating means. In addition to having a resist removing device, it has a control means for automatically performing the introduction of the reactive gas from the scattered resist removing device and the irradiation of ultraviolet rays for each introduction process of impurities to a predetermined amount of wafers. Ion implanter.