JP2001167728A - Ion injection apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning method able to safely carry out source maintenance by minimizing generation of HF gas, although outside air enters into a source housing by opening thereof. SOLUTION: When emitting a beam using fluoride compound gas, fluoride compound, which is deposited on an inner surface of source mount flange and a source housing, produces poisonous and corrosive HF gas by reacting with moisture of the air in the case the air enters into the source housing. However, since HF gas is generated from the fluoride compound by contacting the air and the fluoride compound, absolute amount of fluoride is decreased. An introducing path of the air or a discharge system is provided at the inner surface of source mounting flange, within the source housing, or at ion beam line, whereby the introduction of open air is performed after work, while HF gas, which is produced by the reaction of the deposited fluoride compound with active gas such as water in the open air, is forcibly eliminated while discharged by the discharge system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of cleaning an ion source or an ion beam line using a fluoride compound gas as an ion source and an ion source or an ion beam apparatus having cleaning means. It can be applied to

[0002]

2. Description of the Related Art FIG. 1 shows a conventional vacuum system of a typical ion implantation apparatus. Source housing 1,
The beam lines 2 and 14, the disk chamber 3 and the like are evacuated by the roughing pumps 12 and 13 and then evacuated by the pumps 6, 7, 8, 9 and 10 until the vacuum is further increased. Source housing 1, beam lines 2 and 1
4. After the disk chamber 3 reaches high vacuum,
The source gas is supplied from the source gas chamber G to the source housing 1 to generate ions, and the ions extracted from the source housing 1 form an ion beam and reach the substrate of the disk chamber from the beam line.

Conventionally, the elements for ion implantation, Si and A
Fluoride compound gas such as s, P, B, Ge, etc., SiF4, A
When ion implantation is performed using sF3, PF3, BF3, GeF4, or the like, an ion beam is emitted using the fluoride compound gas as a source gas, and then precipitates generated from the fluoride compound gas are generated. In order to reduce the amount of precipitates of the secondary fluorinated compound by reacting the secondary fluorinated compound (GeF2 in the case of Ge) with moisture in the air,
The process of putting air into the source housing 1 through the two-way valve Vc6, purging with air, and then evacuating with the RP2 roughing pump 13 and purging with air has been repeated. However, in the repetition of the above-mentioned purging and roughing, it takes more than half a day until the air is put into the source housing 1 and the deposited secondary fluorinated compound disappears and the generation of HF gas becomes less than the allowable exposure limit (3 ppm). Met. Further, since corrosive HF gas passes through the RP2 roughing pump 13, the RP2 roughing pump 13
Must be selected in consideration of the passage of HF gas, and it was made harmless by the external exhaust system 17 after roughing, but it was not sufficient. Furthermore, in the above-described method of purging air, a sufficient amount of purging can be performed because air hardly passes through a portion where a large amount of fluoride is precipitated, and an inner surface of a flange portion where the source assembly of the source housing 1 is mounted on the source housing. -There was a possibility that HF gas would be generated during source maintenance even if it was thought that rough evacuation was performed. When performing maintenance on the source housing 1, since it is difficult to determine whether or not the fluoride compound gas has been used from the time of the maintenance to the present, it is determined whether or not HF gas is generated even if the air enters the source housing 1 during the maintenance. It was difficult to do.

Further, since there is no compact and inexpensive abatement material which efficiently removes all toxic and corrosive gases generated by an ion beam apparatus for ion implantation and which can pass through the atmosphere, RP2 roughing is performed. It has been difficult to efficiently install the abatement material for the purpose of protecting the pump 13 and piping before and after it. Also, if the HF gas concentration is always detected by the low concentration HF gas detector whose general measurement range is low concentration around the allowable exposure limit, the detector will break down when high concentration HF gas is generated. there is a possibility. An HF gas measuring device that can measure high-concentration HF gas is an expensive device. Conventionally, even if air enters the source housing, the number of times of air purge and roughing is counted to confirm that the generated HF gas concentration is below the allowable exposure limit (3 ppm).
The number of times the gas concentration was considered to have fallen below a certain value was detected by the detector.

[0005]

SUMMARY OF THE INVENTION Therefore, the objects of the present invention are: Elements for ion implantation, Si, As, P, B, Ge
When a beam is emitted using a fluorinated compound gas such as that described above, the fluoride deposited on the inner surface of the source mounting flange and in the source housing enters the source housing when the atmosphere enters (when the source is removed and the source maintenance is performed). ) Reacts with the moisture in the atmosphere to generate toxic and corrosive HF gas, which is precipitated by introducing the atmosphere (a gas containing moisture) into the deposited secondary fluorinated compound and bringing it into contact. HF gas is generated from the fluorinated compound to reduce the absolute amount of the fluorinated compound deposited, so that the generation of HF gas can be suppressed to a minimum even if the air enters from opening the source housing. So that source maintenance can be performed safely. 2. By exhausting the generated HF gas through the HF gas exhaust pipe, corrosive HF gas is prevented from passing through the roughing pump as in the related art, and the failure of the roughing pump is prevented. 3. By allowing continuous air purging for each operation,
F-gas exhaust time is shortened. 4. Elements for ion implantation, Si, As, P, B, Ge
After emitting a beam using a fluorinated compound gas such as HF gas, that is, when it is predicted that HF gas will be generated when the deposited secondary fluorinated compound is deposited and the air enters the source portion, be sure to exhaust HF gas. Atmospheric purging is performed according to the system sequence, and the concentration of the HF gas in the source housing when the air is introduced into the source housing is set to an allowable exposure limit (3p).
pm) or less. 5. When the above HF gas is generated, high concentration H of 120 ppm or more
Although F gas may be generated, the measurement range generally used at present is the low concentration H of the concentration around the allowable exposure limit.
If the F gas detector detects a high concentration of HF gas that is higher than the allowable value, the detector will fail with a high probability.
Even if the above-mentioned high-concentration HF gas is generated without using an expensive HF gas measuring device capable of measuring the above HF gas concentration, the HF gas exhaust system uses a HF gas detector having a measurement range of 0 to 9 ppm. It can be confirmed that the HF gas concentration in the source housing is equal to or lower than the allowable exposure limit (3 ppm). An object of the present invention is to provide an ion implantation apparatus having such functions.

[0006]

SUMMARY OF THE INVENTION The present invention has the following features. 1 and 2. In an ion source or ion beam line using a fluorinated compound gas as an ion source, an air introduction path and an exhaust system are provided on the inner surface of the source mounting flange, in the source housing, or on the ion beam line, and after the injection operation, the source housing is used for source maintenance. When the inside is opened to the outside air and before the work, the air is introduced through the air introduction path, and the exhaust system is constituted by an exhaust path having a harm removal device and a suction exhaust pump, and the deposited fluoride is The HF gas generated by the reaction between the compound and the active gas such as atmospheric moisture is exhausted while forcibly removing the HF gas by the exhaust system, and the inner surface of the source mounting flange, the source housing, or the ion beam line is exhausted. Purged. 3. The fluoride compound gas is a fluoride compound gas of an element for ion implantation. 4. The fluorinated compound is a secondary fluorinated product generated from a fluorinated compound gas of an element for ion implantation. 5. At least a section of the exhaust system up to the abatement apparatus is configured by an exhaust path formed by HF gas exhaust piping. 6. The location detected by the HF gas detector is changed by a combination of a first three-way valve and a second three-way valve switching valve provided near the HF gas detector in an exhaust path formed by HF gas exhaust piping. 7. Resets the accumulation of the source gas flow rate during the source maintenance, stores the accumulation of the subsequent source gas flow rate in the storage device, and operates the HF gas exhaust system to continuously purge the atmosphere unless the accumulated value of the source gas flow rate is 0. Then, after confirming that the HF gas concentration is equal to or lower than the allowable exposure limit, a display indicating that source maintenance is possible is performed. 8. When the continuous air purge time is measured and it is determined that the HF gas concentration is sufficiently low, the HF gas detector is operated by switching the first three-way valve to confirm that the HF gas concentration is below the allowable exposure limit. Detect and confirm for 1 minute or more. 9. When the HF gas detector is operated by switching the first three-way valve and the HF gas detector indicates a value of 3 ppm or more, the detection is immediately stopped. 10. When the HF gas concentration of the HF gas exhaust system is not detected, the atmosphere in the apparatus is configured to pass through the detector. 11. In an ion source or ion beam line using a fluorinated compound gas as an ion source, an air introduction path and an exhaust system are provided on the inner surface of the source mounting flange, in the source housing, or on the ion beam line, and after the injection operation, the source housing is used for source maintenance. When the inside is opened to the outside air and before the work, the air is introduced through the air introduction path, and the exhaust system is constituted by an exhaust path having a harm removal device and a suction exhaust pump, and the deposited fluoride is The HF gas generated by the reaction between the compound and the active gas such as atmospheric moisture is exhausted while forcibly removing the HF gas by the exhaust system, and the inner surface of the source mounting flange, the source housing, or the ion beam line is exhausted. An ion source configured to be purged; and The on-beam line was applied to the ion implantation. 12. A stationary HF gas detector for confirming that the HF gas concentration is equal to or lower than the allowable exposure limit is provided at the front stage of the abatement apparatus of the exhaust system, and is used in an exhaust path through HF gas exhaust piping.

[0007]

FIG. 2 shows a typical schematic match of the present invention. If the temperature of the arc chamber in the source of the source housing 1 is high, the inside of the source housing may be oxidized when air enters, so that the temperature of the vaporizer in the vicinity of the arc chamber is 70%.
There is a sensor to confirm that the temperature is below ℃. In an ion source or ion beam line using a fluorinated compound gas as an ion source, an air introduction path and an exhaust system are provided on the inner surface of the source mounting flange, in the source housing, or on the ion beam line, and after the injection operation, the source housing is used for source maintenance. When the inside is opened to the outside air and before the work, the air is introduced through the air introduction path, and the exhaust system is constituted by an exhaust path having a harm removal device and a suction exhaust pump, and the deposited fluoride is An HF gas generated by a reaction between the compound and an active gas such as atmospheric moisture is exhausted while forcibly removing the HF gas by an exhaust system.
The inner surface of the source mounting flange, the inside of the source housing, or the ion beam line was purged. The fluoride compound gas is a fluoride compound gas of an element for ion implantation. The fluorinated compound is a secondary fluorinated product generated from a fluorinated compound gas of an element for ion implantation. The location where the HF gas detector detects is changed by a combination of a switching valve for the first three-way valve and the second three-way valve provided near the HF gas detector in the exhaust path of the HF gas exhaust pipe. . Resets the accumulation of the source gas flow rate during the source maintenance, stores the accumulation of the subsequent source gas flow rate in the storage device, and operates the HF gas exhaust system to continuously purge the atmosphere unless the accumulated value of the source gas flow rate is 0. Then, after confirming that the HF gas concentration is equal to or lower than the allowable exposure limit, a display indicating that source maintenance is possible is performed. When the continuous air purge time is measured and it is determined that the HF gas concentration is sufficiently low, the HF gas detector is operated by switching the first three-way valve to confirm that the HF gas concentration is below the allowable exposure limit. Detect and confirm for 1 minute or more. When the HF gas detector is operated by switching the first three-way valve and the HF gas detector indicates a value of 3 ppm or more, the detection is immediately stopped. When the HF gas concentration of the HF gas exhaust system is not detected, the atmosphere in the apparatus is configured to pass through the detector. A stationary HF gas detector for confirming that the HF gas concentration is equal to or lower than the allowable exposure limit is provided at the front stage of the abatement apparatus of the exhaust system, and is used in an exhaust path through HF gas exhaust piping.

[0008] The present HF gas exhaust system is used, for example, after emitting a beam using a fluoride compound gas when fluoride is expected to be deposited on the inner surface of the source mounting flange or in the source housing. First, VC
Open 6 and vent source with N2. When the source reaches atmospheric pressure, close VC6. Open VC2, VC3 and D
Activate the PC. Wait until the negative pressure in the source housing falls below a certain value. If the pressure inside the source housing does not become lower than the predetermined value after a predetermined time, the sequence is stopped because there is an abnormality in the HF gas exhaust system. Next, if the pressure in the source housing is equal to or less than a certain value, the two-way valve VC
1 is opened and the ion source housing 1 is vented with the atmosphere. When the source reaches atmospheric pressure, close VC1. The two-way valves VC2 and VC3 are opened to operate the DPC 11 which is a vacuum pump for suction and exhaust. Wait until the vacuum pressure in the source housing falls below a certain value. If the vacuum pressure in the source housing does not fall below a certain value after a certain time, the sequence is stopped because there is an abnormality in the HF gas exhaust system. By comparing the value of 15 which is the vent sensor S in the state before and after the release of VC1,
It is determined whether C1 has operated normally. With the VC1 opened, the fluoride precipitated on the inner surface of the source mounting flange and the source housing reacts with the introduced moisture in the atmosphere to generate high-concentration HF gas. Also,
Since the vacuum pump DPC operates continuously, the HF gas can be continuously generated and HF gas can be positively generated and exhausted by a dedicated pipe.

[0009] The generated HF gas is removed by FC, which is a removal device installed in the HF gas exhaust system.
After passing through the DPC, the FC may be installed after the DPC if the DPC has corrosion resistance to HF gas.
Also, if there is equipment to be excluded outside the apparatus, the FC need not be installed inside the apparatus. If the integrated value of the source gas flow rate is 0 or more, continuous atmospheric purge is performed for a fixed time. When the value of the integrated gas flow rate is 0 and the operator decides to perform the atmospheric purge, the atmospheric purge is continuously performed. If the value of the integrated source gas flow rate is 0 and the operator determines not to perform the air purge, the process proceeds to the next step. Since the pressure of the atmosphere in which DC, which is a low-concentration HF gas detector, can detect is near atmospheric pressure, the DPC is stopped, and the air enters from VC1 and the value of 15 as the vent sensor S becomes atmospheric pressure. Vent sensor S
When the pressure 15 becomes the atmospheric pressure, the VC3 is closed so that the gas that has passed through the detector DC from the source housing side does not enter the detector again. Since the pressure of the atmosphere from which gas is exhausted through DC must also be near atmospheric pressure,
Open the two-way valve VC4. And the first three-way valve V01
And the second three-way valve V02 are operated to detect the HF gas concentration in the source housing.

In the next step, if the HF gas concentration is equal to or higher than the allowable exposure limit of 3 ppm, V01 and V02 are activated to prevent the high concentration HF gas from continuously passing through the detector. VC
After opening the VC3 and closing the VC4, the DPC is operated, and the continuous air purge is performed again for a certain period of time to return to the previous step. Specified number of detectors DC, allowable exposure limit (3 ppm)
If the above concentration is indicated, there is a possibility that the detector has failed, so the processing is abnormally terminated. In this step, the HF gas concentration is detected for one minute, and the HF gas concentration is set to the allowable exposure limit of 3 pp.
m or less, operate the three-way valves V01 and V02 to
Open VC3 and then close VC4. Since the HF gas is not generated even if the atmosphere enters the source housing 1, the value of the integrated HF gas flow rate is set to zero.

[0011] Compared with the prior art sequence of repetition of air purge and roughing, the DPC is operated with VC1, VC2, and VC3 open, so that air purge can be performed continuously. This makes it possible to reduce the HF gas exhaust sequence operation time to about 1/12 or less as compared with the conventional sequence. Further, since the HF gas is actively generated and exhausted through the exhaust line, the abatement material can be installed in the exhaust line, preventing the HF gas from flowing to the outside of the apparatus, and preventing the exhaust line from flowing out. To prevent the pump used in the device from being exposed to the HF gas and malfunctioning. HF gas can be efficiently removed because it is only necessary to install a removing material.

Since the air introduction valve VC1 is attached to the source head, the air can be efficiently passed through the inner surface of the source mounting flange on which a large amount of fluoride is deposited. When the source maintenance is possible, the accumulation of the source gas flow is reset, and the subsequent accumulation of the source gas flow is stored in the workstation. When the HF gas exhaust system is operated, continuous air purge is performed and the HF gas concentration is set to the allowable exposure limit (3p) unless the source gas flow rate integration is 0.
pm) and then confirming that source maintenance is possible.

The measurement range 0 generally used at present
〜9 ppm HF gas detectors fail with a high probability of detecting high concentrations of HF gas. In the present invention, the continuous air purge time is measured, and when it is determined that the HF gas concentration has become sufficiently low, V01 (three-way valve) and V02 (three-way valve) are determined.
Operates for about 1 minute or more to confirm that the HF gas concentration is below the allowable exposure limit value. V01 and V02
When the detector operates, if the detector indicates a value of 3 ppm or more, it is possible to immediately stop the detection and prevent the detector from being decisively damaged. Further, once the stationary HF gas detector is stopped, it takes about 3 hours until the sensitivity becomes stable, so it is necessary to operate the detector at all times. In the present invention, when the HF gas concentration of the HF gas exhaust system is not detected, the atmosphere in the apparatus is passed through a detector so that a stable sensitivity can be obtained at any time.

According to the present invention, in an ion source and an ion beam line using a fluoride compound gas as a source of an ion source, when the inside of a source housing is opened to the outside air by a source maintenance or the like after an implantation operation, a source mounting flange is required before the operation. The HF gas is generated by purging the inner surface, the inside of the source housing or the ion beam line by introducing air, and reacting the precipitated fluoride compound with an active gas such as moisture in the air to generate HF gas. An ion source or an ion beam apparatus or an ion beam line cleaning method and apparatus, wherein the exhaust gas is exhausted while being harmed by an exhaust path and an exhaust system. An ion source and an ion beam line were applied to the ion implanter. Fluorinated compound gas is a fluorinated compound gas such as Si, As, P, B, Ge or the like for ion implantation, SiF4, AsF3, PF3, BF
3, GeF4 and the like. The fluorinated compound is a secondary fluorinated product generated from a fluorinated compound gas of an element for ion implantation. In the case of GeF4, it is GeF2. HF
A stationary HF gas detector having a measurement range of 0 to 9 ppm for confirming that the gas concentration is equal to or lower than the allowable exposure limit is used in an exhaust path using HF gas exhaust piping. There is a mechanism that can change the detection location of the HF gas detector by a three-way valve in the exhaust path with HF gas exhaust piping so that stable sensitivity is always obtained. Reset source gas flow rate accumulation during source maintenance, store the subsequent source gas flow rate accumulation in the workstation,
When the HF gas exhaust system is operated, continuous air purge is performed to confirm that the HF gas concentration is equal to or lower than the allowable exposure limit (3 ppm), and then display that source maintenance is possible is performed, unless the integration of the source gas flow rate is 0. When the continuous air purge time is measured and it is determined that the HF gas concentration has become sufficiently low, V01 (three-way valve) and V02 (three-way valve) are activated and the HF gas concentration is below the allowable exposure limit. It is confirmed by detecting about 1 minute or more. V01 and V
When 02 is activated, if the detector shows a value of 3 ppm or more, the detection is immediately stopped. Compared to the conventional sequence of atmospheric purge / roughing repetition, the DPC is operated by opening the two-way valve for introducing the atmosphere and subsequently opening the two-way valve on the DPC path side from the source housing. It became possible to perform atmospheric purge. This makes it possible to reduce the HF gas exhaust sequence operation time to about 1/12 or less as compared with the conventional sequence. When the HF gas concentration of the HF gas exhaust system is not detected, the atmosphere in the apparatus is configured to pass through the detector. Since the atmosphere introduction valve VC1 is attached to the source head, the atmosphere can be efficiently passed through the inner surface of the source mounting flange where a large amount of fluoride is deposited.
Once the stationary HF gas detector is stopped, it takes about 3 hours for the sensitivity to stabilize.
When the HF gas concentration of the HF gas exhaust system is not detected, the atmosphere in the apparatus is passed through the detector to obtain stable sensitivity at any time.

[0015]

When the fluoride is expected to be deposited on the inner surface of the source mounting flange or in the source housing, the HF gas exhaust system is used after emitting a beam using a fluoride compound gas. . The operation is as follows. 1. If the temperature of the arc chamber is high, it may be oxidized when air enters, so that the vaporizer temperature near the arc chamber is confirmed to be 70 ° C. or less to prevent oxidation. 2. Open VC6 and vent source with N2. When the source reaches atmospheric pressure, close VC6. 3. Open VC2 and VC3 to activate DPC. Wait until the negative pressure in the source housing falls below a certain value. If the pressure inside the source housing does not become lower than the predetermined value after a predetermined time, the sequence is stopped because there is an abnormality in the HF gas exhaust system. 4. If the pressure in the source housing is below a certain value, VC1
Open and vent. It is determined whether the VC1 has operated normally by comparing the value of 15 which is the vent sensor S in a state before and after the VC1 is opened. When the VC1 is opened, the fluorinated compound deposited on the inner surface of the source mounting flange and the source housing reacts with the moisture in the atmosphere to generate a high-concentration HF gas. Also,
Since the DPC operates continuously, the HF gas can be continuously generated and the HF gas can be positively generated and exhausted through a dedicated pipe. 5. The generated HF gas is removed by the FC installed in the HF gas exhaust system. After that, it passes DPC,
FC is DP if DPC has corrosion resistance to HF gas
It may be installed after C. Also, if there is equipment to be excluded outside the apparatus, the FC need not be installed inside the apparatus. 6. If the integrated value of the flow rate of the source gas is equal to or greater than 0, the continuous air purge is performed for a certain time. When the value of the integrated flow rate of the source gas is 0 and the operator decides to perform the atmospheric purge, the atmospheric purge is continuously performed. If the integrated value of the flow rate of the source gas is 0 and the operator decides not to perform the air purge, the process proceeds to the next step. 7. Since the pressure of the atmosphere in which DC can be detected is near the atmospheric pressure, the DPC is stopped, and the air enters from VC1 and the value of 15 as the vent sensor S becomes atmospheric pressure. When the pressure of the vent sensor S reaches the atmospheric pressure, the VC3 is closed so that gas that has passed through the detector from the source housing side does not enter the detector again. VC4 is opened because the pressure of the atmosphere through which the gas is exhausted through the DC must also be near atmospheric pressure. By operating V01 and V02, the HF gas concentration in the source housing is detected. 8. In this step, the concentration of HF gas is
pm or more, activate V01 / V02 to increase the concentration of H
Prevents F gas from continuously passing through the detector. After the VC3 is opened and the VC4 is closed, the DPC is operated and the continuous air purge is performed again for a certain period of time to return to the previous step. If the detector shows a concentration equal to or higher than the allowable exposure limit (3 ppm) for a specified number of times, the detector may be out of order and terminate abnormally. 9. In the next step, the HF gas concentration is detected around 1 minute, and if the HF gas concentration is 3 ppm or less of the allowable exposure limit, V
01 and V02 are operated to open VC3 and close VC4. Since the HF gas is not generated even if the atmosphere enters the source housing, the integrated value of the flow rate of the HF gas is set to zero.

[0016]

According to the present invention, there are provided: When a beam is emitted using a fluorinated compound gas, the secondary fluorine compound deposited on the inner surface of the source mounting flange and in the source housing is removed when the air enters the source housing (when the source is removed and the source maintenance is performed). ) Reacts with the moisture in the atmosphere to generate toxic and corrosive HF gas, but the air (moisture-containing gas) is brought into contact with the deposited secondary fluorine compound and brought into contact with the deposited secondary fluorine compound. Generating HF gas from the compound,
The absolute amount of the fluorinated compound precipitated is reduced, and even if the air enters by opening the source housing, the generation of HF gas is minimized, so that the source maintenance can be performed safely. 2. By exhausting the generated HF gas through the HF gas exhaust pipe, it is possible to prevent the corrosive HF gas from passing through the roughing pump as in the related art, thereby preventing the roughing pump from malfunctioning. 3. By allowing continuous air purging for each operation,
The F gas exhaust time can be reduced. 4. After emitting a beam using a fluoride compound gas, that is, when it is predicted that HF gas will be generated when the fluoride compound is deposited and the air enters the source part, HF gas must be emitted.
Purging the atmosphere by gas exhaust system sequence,
It can be confirmed that the concentration of the HF gas in the source housing when the air is introduced into the source housing is equal to or lower than the allowable exposure limit (3 ppm). 5. When the above HF gas is generated, high concentration HF exceeding 100 ppm
Although gas may be generated, the measurement range generally used at present is a low concentration HF with a concentration around the allowable exposure limit.
If the gas detector detects a high concentration HF gas that is higher than the allowable value, the detector will fail with a high probability, so without using an expensive HF gas measurement device that can measure HF gas concentration of several hundred ppm or more, Even when the high concentration HF gas is generated,
HF gas exhaust system with measurement range of 0-9ppm HF
Using a gas detector, it can be confirmed that the HF gas concentration in the source housing is below the allowable exposure limit (3 ppm). 6. Since the HF gas is actively generated and exhausted through the exhaust line, the abatement material can be installed in the exhaust line, preventing the HF gas from flowing to the outside of the apparatus and using the exhaust line. The pump can be prevented from being damaged by exposure to HF gas. HF gas can be efficiently removed because it is only necessary to install a removing material. 7. The continuous air purge time was measured, and when it was determined that the HF gas concentration was sufficiently low, V01 (three-way valve) and V02 (three-way valve) were activated, and the HF gas concentration was below the allowable exposure limit. It detects and confirms that there is more than 1 minute, but if the detector shows a value of 3 ppm or more, it is possible to stop the detection immediately and prevent the detector from being decisively damaged. It has excellent features.

[0017]

[Brief description of the drawings]

FIG. 1 is a diagram showing a conventional configuration.

FIG. 2 is a diagram showing a schematic configuration of a main part of an ion implantation apparatus to which the present invention is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Source housing 2 Beam line 3 Disk chamber 4 Detoxifier FC 5 HF gas detector DC 11 Vacuum pump DPC 13 RP2 roughing pump VO1 First three-way valve VO2 Second three-way valve

Claims (12)

[Claims] In an ion source or ion beam line using a fluoride compound gas as an ion source, an air introduction path and an exhaust system are provided on the inner surface of a source mounting flange, in a source housing, or on an ion beam line, and after the implantation operation, At the time of opening the inside of the source housing to outside air for maintenance or the like and before the work, the atmosphere is introduced by the introduction path of the atmosphere, and the exhaust system is configured by an exhaust path having a harm removal device and a suction exhaust pump, The HF gas generated by the reaction between the fluorinated compound and the active gas such as moisture in the atmosphere is exhausted by the exhaust system while forcibly removing the HF gas. Alternatively, the ion beam line is purged. The cleaning method of ion beam line. 2. An ion source or ion beam line using a fluoride compound gas as an ion source, an air introduction path and an exhaust system are provided on the inner surface of the source mounting flange, in the source housing, or on the ion beam line. When opening the inside of the source housing to outside air for maintenance or the like and before the work, the atmosphere is introduced by the introduction path of the atmosphere, and the exhaust system is configured by an exhaust path having a harm removal device and a suction exhaust pump, The HF gas generated by the reaction between the precipitated fluorinated compound and the active gas such as moisture in the atmosphere is exhausted by the exhaust system while forcibly removing the HF gas, and the inner surface of the source mounting flange and the source housing are exhausted. The inside or the ion beam line is purged. Ion source or ion beam apparatus according to the cleaning method that the ion beam line. 3. The ion beam line cleaning method according to claim 1, wherein the fluorinated compound gas is a fluorinated compound gas of an element for ion implantation. 4. The method for cleaning an ion beam line according to claim 1, wherein the fluorinated compound is a secondary fluorinated product generated from a fluorinated compound gas of an element for ion implantation. 5. The method for cleaning an ion beam line according to claim 1, wherein at least a section of the exhaust system up to the abatement apparatus is constituted by an exhaust path using HF gas exhaust piping. . 6. An HF gas in an exhaust passage formed by HF gas exhaust piping.
6. The structure according to claim 5, wherein a portion to be detected by the HF gas detector is changed by a combination of a first three-way valve and a second three-way valve switching valve provided near the gas detector. How to clean the ion beam line. 7. The source gas flow integration is reset during source maintenance, and the subsequent source gas flow integration is stored in a storage device. When the HF gas exhaust system is operated, the integrated value of the source gas flow is not zero. 2. The method for cleaning an ion beam line according to claim 1, wherein a continuous air purge is performed as long as possible, and after confirming that the HF gas concentration is equal to or lower than an allowable exposure limit, a display indicating that source maintenance is possible is performed. 8. A continuous atmospheric purge time is measured, and when it is determined that the HF gas concentration is sufficiently low, the HF gas detector is operated by switching the first three-way valve, and the HF gas concentration is set to the allowable exposure limit value. 7. The method for cleaning an ion beam line according to claim 6, wherein the following is detected and confirmed for at least one minute. 9. When the HF gas detector is operated by switching the first three-way valve, if the HF gas detector shows a value of 3 ppm or more, the detection is immediately stopped. 7. The method for cleaning an ion beam line according to claim 6. 10. The cleaning method for an ion beam line according to claim 6, wherein the air in the apparatus is passed through an HF gas detector when the HF gas concentration of the HF gas exhaust system is not detected. . 11. The method for cleaning an ion beam line according to claim 2, wherein the ion source and the ion beam line are applied to ion implantation. 12. A stationary HF gas detector for confirming that the HF gas concentration is equal to or lower than an allowable exposure limit is provided in a preceding stage of the abatement apparatus of the exhaust system, and an exhaust path through HF gas exhaust piping is provided. 3. The method for cleaning an ion beam line according to claim 1 or 2, wherein the cleaning method is used.