JP2000286249A - Particle removing system and method therefor, and impurity substance detecting system and method therefor, and particle detecting system and method therefor, and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To electrically make neutral and remove particles which are generated in a treatment apparatus. SOLUTION: A treatment device 100 carries out prescribed treatment to a substrate. A wire source 200 has particles having positive or negative charge irradiated on charged particles which are generated by carrying out the prescribed treatment to the substrate in the treatment device 100 for electrically making the particles neutral. Afterwards, a computer 300 controls a vacuum apparatus or the like, not shown, for sucking and removing the particles which turned electrically neutral.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a particle removal system for detecting and removing the presence of impurities generated in a processing chamber, an impurity detection system, a particle detection system, a particle removal method, an impurity detection method, and a method for detecting impurities. More particularly, the present invention relates to a particle removal system for removing particles after neutralizing particles electrically, an impurity detection system, a particle detection system, a particle removal method, an impurity detection method, and a particle detection method.

[0002]

2. Description of the Related Art LSI (large-scale integrated circuit) electrodes, etc.
When formed by etching using plasma (dry etching), a large number of particles are generated in the processing chamber. The reaction product generated by the etching adheres to the inner wall of the processing chamber,
It is caused by peeling. In an etching process of a semiconductor substrate, after a semiconductor substrate is electrostatically attracted to a predetermined position in a processing chamber, a processing gas is introduced into the processing chamber, and a high-frequency voltage is applied to etch the semiconductor substrate. After etching is completed, application of a high-frequency voltage, supply of processing gas,
In addition, an inert gas (purge gas) that does not contribute to etching is supplied in order to stop the electrostatic adsorption of the semiconductor substrate and quickly discharge the processing gas.

[0003] The number of particles generated in the etching process can be obtained by irradiating a laser into the processing chamber and photographing the scattered light from the particles with a CCD (Charge Coupled Device) camera. According to the measurement results obtained in this manner, almost no particles are present during the etching, but when the application of the high-frequency voltage is stopped, a large number of particles are generated temporarily. It turned out to be frequent. Further, when the image capturing the scattered light of the laser radiated on the particles was examined in detail, the particles tended toward the substrate at the end of the application of the high-frequency voltage, and tended toward the exhaust port when the purge gas was introduced. That is,
Particles charged by the application of a high-frequency voltage are suspended by the high-frequency voltage during etching, but because of the low viscosity of the processing gas, they are attracted to the semiconductor substrate with gravity or residual charge by the stop of the high-frequency power supply and fall. Then, it is considered that the gas is directed to the exhaust port by the purge gas introduced thereafter.

[0004] When the particles adhere to the semiconductor substrate as described above, the performance of an LSI or the like as a product is reduced. Therefore, a technique for preventing and suppressing the adhesion of the particles is disclosed in Japanese Patent Application Laid-Open No. 5-29272. Kaihei 5-2672
34, JP-A-6-216087, JP-A-7-216087
-22400, JP-A-7-58033, JP-A-8-115903, and JP-A-9-306
No. 892. JP-A-5-29272
In the technique disclosed in Japanese Patent Application Laid-Open Publication No. H11-115, a cover and a driving device for covering an etching target are provided near the etching target. After completion of the etching, the cover is moved into the vacuum chamber by the driving device to prevent particles from adhering to the etching target.

In the technique disclosed in Japanese Patent Application Laid-Open No. Hei 5-267234, a pair of particle counter electrodes are provided perpendicular to the high frequency electrode in order to collect particles floating between the pair of high frequency electrodes. . In order to prevent the particles adsorbed on the particle counter electrode from re-floating, an openable cover is provided on the particle counter electrode. According to the technique disclosed in Japanese Patent Application Laid-Open No. 6-216087, after processing of a semiconductor substrate is completed,
A non-reactive plasma is generated, and particles attached to the surface of the semiconductor substrate with a weak force are pulled up. The particles lifted from the semiconductor substrate are removed by flushing with an inert gas.

According to the technique disclosed in Japanese Patent Application Laid-Open No. 7-22400, a pair of high-frequency electrodes for generating plasma in a processing chamber and a material for peeling off a substance attached to the high-frequency electrodes are used for processing a semiconductor substrate. A release electrode is provided. Then, after the etching process, in order to remove a reaction product attached to one of the high-frequency electrodes, a release electrode is arranged between the pair of high-frequency electrodes, and between the one high-frequency electrode to which the reaction product is attached and the release electrode. Apply high frequency voltage to
The reaction products attached to the high frequency electrode are removed. In the technique disclosed in Japanese Patent Application Laid-Open No. 7-58033, a shutter that can be opened and closed is provided above a semiconductor substrate so as to be close to the semiconductor substrate. After the processing of the semiconductor substrate is completed, the shutter is closed to prevent particles from adhering to the semiconductor substrate.

In the technique disclosed in Japanese Patent Application Laid-Open No. HEI 8-115903, a pair of electrodes in a processing chamber are covered with a material which reacts with a halogen compound of tungsten (W) to generate a volatile product. Reaction products are prevented from adhering to this electrode. Also, by controlling the flowing direction of the processing gas so that the processing gas does not directly hit the semiconductor substrate, particles are prevented from adhering to the semiconductor substrate. According to the technique disclosed in Japanese Patent Application Laid-Open No. 9-306892, an ultraviolet light source is provided in a processing chamber, and ultraviolet light is emitted each time processing of a semiconductor substrate is completed, thereby removing organic compounds deposited in the processing chamber. I have.

[0008]

In the conventional method of removing the gas and particles in the processing chamber by introducing a purge gas after the end of the etching, the charge of the particles cannot be eliminated. Therefore, after the high-frequency power supply is turned off, the particles are attracted to the semiconductor substrate or the like by gravity and electrostatic force, and in order to remove the particles without attaching them to the semiconductor substrate, the supply speed of the purge gas must be increased. There is a problem.

In the technique disclosed in Japanese Patent Application Laid-Open No. 5-29272, a cover for covering the object to be etched and a driving device therefor are provided near the object to be etched. For this reason, when the cover is driven, particles deposited and adhered to the cover and its driving part may fly up. Therefore, there is a problem that the provision of the cover as described above may cause particles to adhere to the semiconductor substrate. In the technique disclosed in Japanese Patent Application Laid-Open No. 5-267234, a particle countermeasure electrode for adsorbing particles is provided between high-frequency electrodes. Therefore, there is a problem that only particles floating between the high-frequency electrodes can be efficiently removed. Although an openable cover is provided to prevent the particles from re-floating, there is a problem that the particles may re-float by opening and closing the cover.

In the technique disclosed in Japanese Patent Application Laid-Open No. 6-216087, particles that have already adhered to a semiconductor substrate are removed. Therefore, there is a problem that particles cannot be prevented from adhering to the semiconductor substrate, and particles that adhere to the semiconductor substrate cannot be removed with a strong force. In the technique disclosed in Japanese Patent Application Laid-Open No. 7-22400, a reaction product attached to an electrode is removed by applying a high-frequency voltage between a high-frequency electrode and a peeling electrode. Therefore, there is a problem that a reaction product attached to the inner wall of the processing chamber cannot be removed, and generation of particles cannot be prevented.

In the technique disclosed in Japanese Patent Application Laid-Open No. 7-58033, an openable and closable shutter is provided near a semiconductor substrate. Therefore, when the shutter is opened and closed, particles adhering to the shutter and the driving portion of the shutter may re-float, and the re-floated particles adhere to the semiconductor substrate. The technique disclosed in Japanese Patent Application Laid-Open No. HEI 8-115903 can prevent the reaction product from adhering to the electrode, but cannot prevent the reaction product from accumulating in the processing chamber, so that particles are generated. There's a problem. Further, if the processing gas does not directly hit the semiconductor substrate, there is a problem that the particles are attracted to the semiconductor substrate or the like by electrostatic force.

In the technique disclosed in Japanese Patent Application Laid-Open No. 9-306892, an organic compound is removed by ultraviolet rays. However, in a process such as etching, an inorganic compound also accumulates as a reaction product in the processing chamber, and there is a problem that the inorganic compound is not removed by this technique and may be separated into particles. Therefore, the present invention provides a particle removal system, an impurity detection system, a particle detection system, and a particle removal system capable of efficiently removing particles (fine particles) generated when performing a predetermined process on a substrate and manufacturing a highly reliable apparatus. It is an object of the present invention to provide a removal method, an impurity detection method, and a particle detection method.

[0013]

In order to achieve the above object, a particle removal system according to a first aspect of the present invention is a particle removal system for removing particles generated when performing a predetermined process in a processing chamber. A system for irradiating particles having a positive or negative charge into the processing chamber to electrically neutralize particles present in the processing chamber, and after irradiating the particles with the irradiating means, Removing means for introducing gas into the processing chamber and sucking and removing electrically neutral particles.

According to the present invention, since the particles generated in the processing chamber are electrically neutralized, the particles may be attracted to the residual charge of the substrate or the like to be subjected to the predetermined processing in the processing chamber. Absent. Therefore, after performing a predetermined process, a gas can be introduced to efficiently remove particles, and the performance and reliability of the manufactured device can be improved. The irradiating means may irradiate at least one of positrons, electrons, positive ions, and negative ions as the particles.

[0015] An impurity detection system according to a second aspect of the present invention is an impurity detection system for detecting the presence of impurities generated when a predetermined process is performed in a processing chamber. Irradiating means for irradiating emitted positrons into the processing chamber, first detecting means for detecting gamma rays generated by pair annihilation of the positrons and electrons in the processing chamber, and a detection result of the detecting means. Determining means for determining whether an impurity is present in the processing chamber. According to the present invention, the presence of an impurity can be detected by irradiating a positron into the processing chamber and detecting a gamma ray emitted by pair annihilation. Therefore, the presence of impurities can be detected without opening the processing chamber, and the operation efficiency of the processing chamber can be improved.

[0016] The apparatus further comprises a second detecting means for detecting a gamma ray emitted when the positron is emitted from the radioisotope, wherein the discriminating means detects the gamma ray by the first detecting means and the second detecting means. The positron lifetime may be determined from the result to determine whether or not an impurity exists in the processing chamber. The determining means obtains the Doppler spread of the energy of the gamma ray from the detection result of the first detecting means, and determines whether or not the obtained Doppler spread matches a reference Doppler spread. It may be determined whether or not an impurity exists in the chamber.

Irradiating means for irradiating particles having a positive or negative charge into the processing chamber to electrically neutralize impurities present in the processing chamber; and irradiating the particles with the irradiating means. A removing unit that introduces gas into the processing chamber and removes electrically neutral impurities, and the determination unit determines that the impurities exist in the processing chamber. The irradiation means may irradiate the particles, and the irradiation means may remove the impurities after the irradiation of the particles by the irradiation means. In this way, the impurities can be removed after the presence of the impurities is detected. Therefore, the interruption of the substrate processing can be minimized, and the operation efficiency of the processing chamber can be improved. The determining means may determine whether or not at least one of particles floating in the processing chamber and deposits attached to an inner wall of the processing chamber exists as the impurity.

A particle detection system according to a third aspect of the present invention is a particle detection system for detecting the presence of particles generated when a predetermined process is performed in a processing chamber, the system being installed in the processing chamber. Radiating means for radiating particles having a positive or negative charge, and in the processing chamber, disposed at a position facing the radiating means, of the particles radiated from the radiating means, the number of flying particles Counting means for counting, it is determined whether or not the difference between the number of particles counted by the counting means and the reference number of particles match within a predetermined range, and if it is determined that they do not match, the processing chamber And determining means for determining that a particle exists in the inside. According to the present invention, the presence of particles can be detected by detecting the number of flying particles. Therefore, the presence of particles can be detected without releasing the processing chamber, and the operation efficiency of the processing chamber can be improved.

The radiating means includes a positron as the particle,
At least one of an electron, a positive ion, and a negative ion may be emitted. Irradiation means for irradiating particles having a positive or negative charge into the processing chamber to electrically neutralize particles existing in the processing chamber,
A removing unit that introduces gas into the processing chamber after the irradiation of the particles by the irradiation unit, and suctions and removes electrically neutral particles. When it is determined that there is a particle inside, the irradiating unit may irradiate the particle, and after the irradiation of the particle by the irradiating unit, the removing unit may remove the particle. This way,
After detecting the presence of the impurity, the impurity can be removed. Therefore, the interruption of the substrate processing can be minimized, and the operation efficiency of the processing chamber can be improved.

A particle removing method according to a fourth aspect of the present invention is a particle removing method for removing particles generated when performing a predetermined process in a processing chamber. Irradiating charged particles to electrically neutralize particles present in the processing chamber; and, after irradiating the particles in the irradiating step, introducing a gas into the processing chamber, And removing the neutralized particles by suction. The irradiation step may include a step of irradiating at least one of positrons, electrons, positive ions, and negative ions as the particles.

An impurity detection method according to a fifth aspect of the present invention is an impurity detection method for detecting the presence of an impurity generated when a predetermined process is performed in a processing chamber. An irradiation step of irradiating the emitted positrons into the processing chamber, a first detection step of detecting a gamma ray generated by pair annihilation of the positrons and electrons in the processing chamber, and a detection result of the detection step. Determining whether particles are present in the processing chamber.

The method may further include a second detecting step of detecting a gamma ray emitted when the positron is emitted from the radioisotope, wherein the determining step includes the first detecting step and the second detecting step.
The method may further include a step of determining a positron lifetime from the detection result of the detection step, and determining whether or not an impurity exists in the processing chamber. The determining step obtains the Doppler spread of the energy of the gamma ray from the detection result of the first detecting step, and determines whether or not the obtained Doppler spread matches a reference Doppler spread. A step of determining whether or not an impurity is present in the chamber may be provided.

An irradiation step of irradiating particles having a positive or negative charge into the processing chamber to electrically neutralize particles existing in the processing chamber; and, after irradiating the particles in the irradiation step, A removing step of introducing a gas into the processing chamber and sucking and removing electrically neutral particles, and further comprising:
When it is determined that particles are present in the processing chamber, the method may further include a step of irradiating the particles in the irradiation step, and irradiating the particles in the irradiation step, and removing and removing impurities in the removal step. Good. The determining step includes a step of determining whether at least one of particles floating in the processing chamber and deposits attached to the processing chamber inner wall is present as the impurity. Is also good.

A particle detection method according to a sixth aspect of the present invention is a particle detection method for detecting the presence of particles generated when a predetermined process is performed in a processing chamber. A radiation step of emitting particles having a positive or negative charge, and a position where the particles in the processing chamber are emitted are opposed to each other, and among the particles emitted in the emission step, flying particles The counting step of counting the number, the difference between the number of particles counted in the counting step and the reference number of particles is determined whether or not they match within a predetermined range, and when it is determined that they do not match,
A determining step of determining that particles are present in the processing chamber.

In the radiation step, positrons are used as the particles,
The method may include a step of emitting at least one of electrons, positive ions, and negative ions. An irradiation step of irradiating particles having a positive or negative charge into the processing chamber to electrically neutralize particles present in the processing chamber; and, after irradiating the particles in the irradiation step, And removing the electrically neutral particles by introducing gas into the processing chamber, wherein the irradiating is performed when it is determined in the determining step that particles are present in the processing chamber. The method may further include a step of irradiating the particles in the step and, after irradiating the particles in the irradiation step, sucking and removing the particles in the removing step.

A computer-readable recording medium according to a seventh aspect of the present invention is a computer-readable recording medium that controls a radiation source to irradiate particles having a positive or negative charge into a processing chamber, Irradiating means for electrically neutralizing the existing particles, and after irradiating the particles with the irradiating means, controlling a gas source to introduce a gas into the processing chamber, and controlling a vacuum pump. A program for functioning as a particle removal system including a gas introduced into the processing chamber by the gas introduction unit and a removal unit configured to suction and remove electrically neutral particles is recorded.

According to an eighth aspect of the present invention, there is provided a computer-readable recording medium comprising: a computer which controls a radiation source to irradiate a positron into a processing chamber;
By controlling the detector, the positrons irradiated by the irradiating means, detecting means for detecting gamma rays emitted by annihilation with electrons present in the processing chamber, from the detection result of the detecting means, A program for causing the apparatus to function as a particle detection system including: a determination unit configured to determine whether or not particles exist in the processing chamber.

A particle removing system according to a ninth aspect of the present invention is a particle removing system for removing particles generated when performing a predetermined process in a processing chamber, wherein a negative charge is stored in the processing chamber. An irradiation unit that irradiates the particles having the particles and negatively charges the particles existing in the processing chamber.

The irradiating means includes, as the particles, electrons,
At least one of the negative ions may be irradiated. The irradiating means irradiates the particles,
A charge that is repelled by a negative self-bias potential naturally generated in the processing chamber may be applied to particles in the processing chamber. The apparatus may further include an electrode for adsorbing the negatively charged particles, and voltage applying means for applying a positive voltage to the electrode to adsorb the negatively charged particles to the electrode.

The particle removing system, the impurity detecting system, and the particle removing system according to the first to eighth aspects of the present invention,
Particles may be removed by combining at least one of the particle detection system, the particle removal method, the impurity detection method, the particle detection method, and the recording medium with the particle removal system according to the ninth aspect. .

A particle removing system according to a tenth aspect of the present invention is a particle removing system for removing particles generated when performing a predetermined process in a processing chamber. It is characterized by comprising charging means for causing particles to enter into the bulk plasma by gradually lowering the power and for negatively charging the particles by the electron current of the plasma.

[0032] The charging means may gradually reduce the high-frequency power to apply to the particles in the processing chamber a charge that is repelled by a negative self-bias potential naturally generated in the processing chamber. . An electrode for adsorbing the negatively charged particles,
Voltage applying means for applying a positive voltage to the electrode to attract the negatively charged particles to the electrode may be further provided.

The particle removing system, the impurity detecting system, and the particle removing system according to the first to ninth aspects of the present invention,
By combining at least one of a particle detection system, a particle removal method, an impurity detection method, a particle detection method, and a recording medium with the particle removal system according to the tenth aspect,
Particles may be removed.

[0034]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) Next, a particle removing method according to a first embodiment of the present invention will be described with reference to the drawings. The processing system used in this particle removal method includes a processing apparatus 100, a radiation source 200, and a computer 300, as schematically shown in FIG. The processing device 100 is connected to a vacuum pump, a gas supply device, and the like (not shown).
A predetermined process (for example, dry etching or the like) is performed on the semiconductor substrate. The detailed configuration of the processing device 100 will be described later. The radiation source 200 includes a radiation source such as an electron, a positron, and an ion.
Irradiate within 00.

The computer 300 controls operations of the processing apparatus 100, the radiation source 200, a vacuum pump and a gas supply device (not shown), and controls the operation of the entire processing system. The computer 300 is provided in advance with programs, hardware, and the like for controlling the entire processing system. FIG. 2 shows a cross-sectional structure of the above-described processing apparatus 100 and a line source 200, a gas supply apparatus,
It is the schematic which shows the state to which the vacuum pump was connected. FIG.
As shown in FIG.
, A processing upper electrode 12, a processing lower electrode 13, an adsorption plate 14, a gas feed path 15, an exhaust port 16, and an inlet 1
7, gas outlet 18, high frequency power supply 19, insulating plate 2
0, a DC power supply 21, a transfer port 22, an irradiation port 23,
It is composed of

The processing chamber 11 has a gas feed path 15, an exhaust port 16, an inlet 17, a transfer port 22, and an irradiation port 23.
Is provided. The gas supply path 15 is connected to a gas supply device, and is provided for introducing a processing gas for performing a predetermined processing on the semiconductor substrate. Exhaust port 16
Is connected to a vacuum pump and is provided for discharging gas and particles (impurities) in the processing chamber 11 to the outside. The introduction port 17 is connected to a gas supply device, and is provided for introducing an inert gas (purge gas) for discharging gas and particles in the processing chamber 11 to the outside. The transfer port 22 is provided for transferring the semiconductor substrate into and out of the processing chamber 11. The irradiation port 23 is directly connected to the radiation source 200, and is provided to irradiate the processing chamber 11 with electrons, positrons, ions, and the like from the radiation source 200.

Processing lower electrode 12 and processing upper electrode 1
3 is disposed so as to face the inside of the processing chamber 11. The processing upper electrode 12 is formed integrally with the gas supply path 15 of the processing chamber 11, has a gas outlet 18, and is grounded. That is, the gas supply path 15 passes through substantially the center of the processing upper electrode 12, and the processing gas supplied from the gas supply path 15 is almost uniformly blown onto the semiconductor substrate by the gas outlet 18. Processing lower electrode 13
Is connected to a high-frequency power supply 19 and the gas outlet 18
A high-frequency voltage is applied to the processing gas blown out of the apparatus to generate plasma. The suction plate 14 is used for the lower electrode 13 for processing.
It is installed above via an insulating plate 20 and connected to a DC power supply 21. The suction plate 14 electrostatically suctions the semiconductor substrate when a voltage is applied from the DC power supply 21.

Next, a method of removing particles as impurities generated in the processing chamber 11 after subjecting a semiconductor substrate to processing such as dry etching using the processing system having the above-described configuration will be described. I do. In addition,
The operations of the processing system described below (on / off of the high-frequency power supply 19 and the DC power supply 21, exhaustion of gas by a vacuum pump, supply of processing gas by a gas supply device, transfer of substrates, and the like) are controlled by the computer 300. . Etching of the semiconductor substrate is performed in the same manner as in the related art. FIG. 3 shows a change in the gas flow rate in the processing chamber 11 and a change in the applied high-frequency voltage in one typical cycle when the semiconductor substrate is subjected to plasma etching.

First, the semiconductor substrate is transferred from the transfer port 22 into the processing chamber 11, and is placed at a predetermined position on the suction plate 14. Next, a highly reactive processing gas such as chlorine is introduced into the processing chamber 11 from the gas supply path 15 and the gas outlet 18. Then, the inside of the processing chamber 11 is evacuated to a predetermined pressure by a vacuum pump. When the inside of the processing chamber 11 reaches a predetermined pressure, the DC power supply 21 and the high-frequency power supply 19 are turned on. As a result, the semiconductor substrate is fixed on the suction plate 14, plasma is generated in the processing chamber 11, and the semiconductor substrate is etched. When the etching is completed, the application of the high-frequency voltage, the supply of the processing gas, and the electrostatic attraction of the semiconductor substrate are stopped.

The reaction products generated by the etching accumulate and adhere to the inner wall and the like of the processing chamber 11. Then, particles that cause deterioration of the performance and the like of the manufactured semiconductor device are generated by the separation of the reaction product. In one cycle of the etching process described above, when the high-frequency power supply 19 is turned off, a large amount of particles are temporarily generated. Therefore, a purge gas is introduced from the inlet 17 to discharge the particles out of the processing chamber 11. However, these particles are charged and are attracted by the residual charge of the suction plate 14 and the semiconductor substrate. Therefore, in order to efficiently discharge the particles by the purge gas, the particles are electrically neutralized as described below.

The particles are positively or negatively charged depending on the state of the plasma used for the etching process, ie, the type of the processing gas used, the processing method, and the like. Therefore, in order to make the particles electrically neutral, it is necessary to first determine whether the particles are positively or negatively charged. In order to check whether the particles are positively or negatively charged, a pump is connected to the exhaust port 16 and further a charge detector having a parallel plate electrode is connected to the pump. Then, a part of the particles is taken out from the exhaust port 16 by the differential evacuation method and is made to enter the charge detector. The charge detector detects the charged state of the particles by measuring the trajectory of the particles incident upon application of a DC voltage to the parallel plate electrodes, which of the positive and negative electrodes the particles are attracted to, and the like.

As described above, the charged state of particles is determined by the type of processing gas to be used, the processing method, and the like. Therefore, whether the particles are charged positively or negatively is measured once for one processing. It should be left. When the charged state of the particles becomes clear as described above, the particles generated in the chamber can be made electrically neutral by the method described below. Hereinafter, a case where the charged state of the particles is changed from negative to neutral will be described. Methods for changing the charged state of particles from negative to neutral include (1) irradiation with white positrons, (2) irradiation with variable energy monochromatic positrons, (3) irradiation with high energy positrons, and (4) irradiation with positive ions. is there. Hereinafter, (1) to (4) will be sequentially described.

(1) White Positron Irradiation In this case, the source 200 of the processing system is
A predetermined region in the processing chamber 11 is irradiated with white positrons having radioactive isotopes such as 8Co and 64Cu and having various energies. Note that a positron is an elementary particle having a positive charge and annihilates with an electron. Since the radiation source 200 is directly connected to the irradiation port 23 of the processing chamber 11,
Positrons are directly irradiated into the processing chamber 11 without annihilation with electrons of various substances in the atmosphere. The irradiated white positrons have various energies, that is, have various collision cross-sectional areas with the particles, and thus collide with the particles existing at various positions in the processing chamber. Since a negatively charged particle has more electrons than in a neutral case, when the white positron is irradiated, the positron annihilates with the electron of the particle. In other words, the number of electrons in the particles decreases,
The particles become electrically neutral.

(2) Irradiation of variable energy monochromatic positron In this case, the source 200 of the processing system is 22Na, 5
A radioisotope such as 8Co or 64Cu, a converter for converting a white positron emitted by the radioisotope into a monochromatic positron having predetermined energy, and a parallel plate electrode for accelerating the monochromatic positron are provided. The energy of the monochromatic positron can be changed by changing the potential difference between the parallel plate electrodes. Monochromatic positrons have a certain energy, that is, the collision cross-section with the particles is almost constant, so that they collide with particles existing in a certain area in the processing chamber. Therefore, by changing the potential difference between the parallel plate electrodes, it is possible to set a region where the monochromatic positrons collide with the particles. The monochromatic positrons emitted from the radiation source 200 into the processing chamber 11 annihilate with the electrons of the particles in the same manner as (1) irradiation of the white positrons. Therefore, the particles are electrically neutral.

(3) Irradiation of High-Energy Positrons In this case, the source 200 of the processing system includes an electron linac (linear accelerator; linear accelerator), a converter, and a parallel plate electrode. Further, the radiation source 200 is directly connected to the irradiation port 23 of the processing chamber 11. The electronic linac accelerates electrons and makes them incident on the converter. The electrons accelerated by the electron linac generate electron-positron pairs by passing through a converter composed of tungsten, tantalum, solid neon, or the like. The positrons thus generated are accelerated by the potential difference between the parallel plate electrodes, and become high-energy positrons. Then, the high-energy positron is applied to the processing chamber 1
As described above, the particles become electrically neutral by being annihilated with the electrons of the particles as described above.

(4) Irradiation of positive ions In this case, the source 200 of the processing system includes an ion source for generating positive ions, and a parallel plate electrode for accelerating the ions and irradiating them into the processing chamber 11. I have. The positive ions irradiated into the processing chamber 11 collide with the negatively charged particles, and the electrons of the negatively charged particles are deprived of the collided positive ions, or the positive ions collide with the particles. Or shared. Therefore, by irradiating with positive ions,
Also in this case, the particles are electrically neutral.

As described above, the particles generated in the processing chamber 11 can be made electrically neutral, and the particles can be prevented from being attracted by the residual charge of the suction plate 14 or the semiconductor substrate. . That is, after the high frequency power supply 19 is turned off, the falling speed of the particles becomes slower than when the particles are not electrically neutralized. Therefore, if a purge gas is introduced into the processing chamber 11 immediately after performing the above processing, particles in the processing chamber 11 can be efficiently removed. Therefore, particles can be prevented from adhering to the semiconductor substrate, and the performance and reliability of the manufactured semiconductor device can be improved.

When the particles are positively charged, electrons and negative ions are used instead of positrons and positive ions, and the electrons and negative ions are treated in the same manner as in (1) to (4) above. What is necessary is just to irradiate the particle in the chamber 11. If the particles are positively charged, the emitted electrons combine with the positively charged particles. The irradiated negative ion electrons are deprived of the particles or are shared by the negative ions and the particles. In this manner, positively charged particles become electrically neutral. Therefore, also in this case, after the processing of the semiconductor substrate is completed, the particles are efficiently discharged by the vacuum pump together with the purge gas without being attracted by the potential potential in the apparatus.

(Second Embodiment) Next, a second embodiment of the present invention will be described.
The particle detection method according to the embodiment will be described. This particle detection method detects the presence of particles as impurities in the processing chamber 11 by measuring the lifetime of positrons. The processing system used in this particle detection method has a configuration in which detectors 400 and 401 are added to the processing system shown in the first embodiment, as schematically shown in FIG.

The processing apparatus 100 has a detection window for connecting the detector 400 in addition to the configuration shown in the first embodiment. The radiation source 200 includes a radioisotope that emits a positron, a parallel plate electrode for accelerating the positron, and the like, and is directly connected to the irradiation port 23 of the processing chamber 11. Then, the radiation source 200 irradiates the positron into the processing chamber 11. The radioactive isotopes included in the radiation source 200 are 22Na, 58Co, 64Cu and the like.
The computer 300 obtains the positron lifetime from the detection results input from the detectors 400 and 401, and determines whether or not particles are generated in the processing chamber 11.

Each of the detectors 400 and 401 has a solid state detector (SSD) composed of a semiconductor detector using germanium or the like, and detects a gamma ray emitted as described below. The detection result is output to the computer 300. Also, the detector 400
Is directly connected to a detection window provided in the processing chamber 11, and the detector 401 is installed in the radiation source 200. Next, the operation of the processing system when detecting the presence of particles generated in the processing chamber 11 using the processing system having the above configuration will be described.

The radiation source 200 applies a predetermined voltage between the parallel plate electrodes, accelerates the positron, and irradiates the inside of the processing chamber 11 with the positron. The positron is emitted from the radioisotope of the radiation source 200, and at this time, light (gamma ray) having an energy of about 1.28 MeV is also emitted as shown in the conceptual diagram of FIG. The emitted positron is accelerated in the radiation source 200, enters the processing chamber 11 and annihilates with the electron, and is two light (gamma rays) having an energy of about 511 keV.
Release. The detector 401 detects a gamma ray emitted when a positron is emitted from the radiation source 200 and outputs the detection result to the computer 300 as needed. On the other hand, the detector 400 detects a gamma ray emitted when a positron annihilates with an electron in the processing chamber 11 and outputs the detection result to the computer 300 as needed.

From the respective detection results, the computer 300 detects the time when the detector 401 provided in the radiation source 200 detects gamma rays, and the detector 400 installed in the detection window of the processing chamber 11 detects gamma rays. Find the time you did. Then, the computer 300 obtains the difference between the two obtained times to obtain the positron lifetime. When no particles are present in the processing chamber 11, the positrons irradiated into the processing chamber 11 annihilate with electrons existing on the inner wall of the processing chamber 11 and emit gamma rays.
In this case, the lifetime of the positron depends on the processing device 100 and the radiation source 20.
Unless the setting of 0 is changed, it is almost constant.

On the other hand, when negatively charged particles are present in the processing chamber 11, the positrons irradiated into the processing chamber 11 collide with the negatively charged particles, and annihilate with the electrons of the particles. To emit gamma rays. This is because the collision cross section between the positron and the negatively charged particles is larger than the collision cross section between the uncharged or positively charged particles. In addition, since particles are distributed at various positions in the processing chamber 11, the emission time of gamma rays due to pair annihilation, that is, the lifetime of positrons varies. From the above, the life of a positron in the absence of particles is measured in advance as a reference life, and the computer 30
A value of 0 determines whether the calculated positron lifetime matches the reference lifetime, and determines whether particles are present in the processing chamber 11.

Therefore, by irradiating the processing chamber 11 with positrons and measuring the positron lifetime as described above, the presence of particles in the processing chamber 11 can be easily detected. Note that the above-described particle detection method is performed after the etching process of the semiconductor substrate is completed, and when the presence of particles is detected, the irradiation of the positron is continued as it is, in the same manner as the particle removal method described in the first embodiment. Alternatively, the particles may be discharged out of the processing chamber 11. With this configuration, the particles can be removed only when the presence of the particles is detected after the end of the etching process. That is, the operation efficiency of the processing system can be improved, and particles can be efficiently removed.

(Third Embodiment) Next, a third embodiment of the present invention will be described.
The particle detection method according to the embodiment will be described. This particle detection method detects the presence of particles as impurities in the processing chamber 11 by measuring the Doppler spread of gamma rays emitted when positrons annihilate with electrons. The processing system used in this particle detection method is substantially the same as the processing system shown in the second embodiment,
No detector 401 is provided. That is, the detector is only the detector 400.

The processing apparatus 100 and the radiation source 200 are substantially the same as in the second embodiment. Computer 300
Determines the Doppler spread of gamma rays from the detection result input from the detector 400 and determines whether or not particles are generated in the processing chamber 11. Detector 40
0 is substantially the same as that of the second embodiment, detects a gamma ray emitted as described below, and outputs the detection result to the computer 300. In addition, detector 4
00 is directly connected to a detection window provided in the processing chamber 11.

Next, the operation of the processing system when detecting the presence of particles generated in the processing chamber 11 using the processing system having the above-described configuration will be described. The radiation source 200 applies a predetermined voltage between the parallel plate electrodes, accelerates positrons, and irradiates the inside of the processing chamber 11 with the positrons. Positrons emitted into the processing chamber 11
As described in the embodiment, two lights (gamma rays) are emitted by annihilation with electrons in the processing chamber 11. Then, the detector 400 detects the energy of the gamma ray emitted by the annihilation of the positron and the electron, and outputs the detection result to the computer 300.

The computer 300 obtains the energy distribution of the gamma ray from the detection result of the detector 400. Then, the computer 300 obtains the Doppler spread of gamma rays from the energy distribution, and detects the presence of particles as described below. Processing chamber 11
If there are no particles in the processing chamber 11
The positrons irradiated into the inside of the substrate annihilate with electrons existing on the inner wall of the processing chamber 11 and emit gamma rays having an energy of about 511 keV. However, in reality, the positron is accelerated, that is, has kinetic energy, and the kinetic energy is distributed within a certain range.
Therefore, the energy of the gamma ray emitted by pair annihilation is shifted from 511 keV by an amount corresponding to the kinetic energy of the positron and distributed within a certain range. The width of this energy distribution is called Doppler spread, and is substantially constant unless the settings of the processing apparatus 100 and the radiation source 200 are changed.

On the other hand, when negatively charged particles are present in the processing chamber 11, the positrons emitted into the processing chamber 11 are charged similarly to the second embodiment. And emits gamma rays, annihilating the electrons of the particles. In this case, since the particles are moving in various directions in the processing chamber 11, the Doppler spread of the gamma rays due to the annihilation is different from that in the case where no particles exist. Therefore, the Doppler spread of gamma rays emitted in the absence of particles is measured in advance as a reference spread, and the computer 300 determines whether the Doppler spread of the gamma rays detected by the detector 400 matches the reference spread. Is determined. And the computer 30
A value of 0 determines whether there is a negatively charged particle in the processing chamber 11.

As described above, the processing chamber 11 is irradiated with the positrons and the Doppler spread of the gamma rays emitted by the pair annihilation is measured.
It is possible to detect the presence of particles inside. Note that the above-described particle detection method is performed after the etching process of the semiconductor substrate is completed, and when the presence of particles is detected, the irradiation of the positron is continued as it is, in the same manner as the particle removal method described in the first embodiment. Alternatively, the particles may be discharged out of the processing chamber 11. With this configuration, the particles can be removed only when the presence of the particles is detected after the end of the etching process. That is, the operation efficiency of the processing system can be improved, and particles can be efficiently removed.

(Fourth Embodiment) Next, a fourth embodiment of the present invention will be described.
A particle detection method according to the embodiment will be described with reference to the drawings. This particle detection method
By measuring the number of positrons flying in the processing chamber 11 during the etching process, the presence of particles as impurities in the processing chamber 11 is detected. The processing system used in this particle detection method is almost the same as the processing system shown in the first embodiment, but the processing apparatus 100 is, as schematically shown on the left side of FIG. 12 is provided with a radiation source 201, and a part of the suction plate 14 is provided with a detector 402.

The radiation source 201 includes a radioisotope for emitting positrons, a parallel plate electrode for accelerating positrons, and the like. Then, the radiation source 201 accelerates the positron with a predetermined potential difference by the parallel plate electrode, and irradiates the positron in the direction of the lower electrode 13 for processing. Further, the radiation source 201 includes ²² Na, ⁵⁸ Co, ⁶⁴ Cu, and the like as radioisotopes. The computer 300 determines whether particles are present in the processing chamber 11 based on the detection result input from the detector 402, as described later. Detector 40
2 is MCP (micro channel plate) or P
An MT (photomultiplier tube) or the like is provided to detect positrons emitted from the radiation source 201, and the number of detected positrons is used as a detection result as a computer 30.
Output to 0.

Next, the operation of the processing system when the presence of particles generated in the processing chamber 11 is detected using the processing system having the above configuration will be described. This particle detection is performed during the etching process of the semiconductor substrate. The radiation source 201 applies a predetermined voltage between the parallel plate electrodes, accelerates the positrons, and irradiates the positrons in the direction of the processing lower electrode 13. As shown schematically on the right side of FIG. 6, the potential potential of the plasma generated during the etching process of the semiconductor substrate is such that
In this case, there is a potential barrier having a magnitude of Vp that hinders the arrival at the detector 402 from 01.
The voltage Vs applied between the working lower electrode 13 and the working upper electrode 12 has one plus the AC voltage _{V AC} and DC reference voltage _{V DC (Vs = V DC +} V
_AC ).

Of the positrons accelerated by the parallel plate electrodes of the radiation source 200, only those having energy exceeding the potential barrier reach the detector 401. The detector 402 detects positrons emitted from the radiation source 201 and uses the detected number of positrons as a detection result as a computer 3
Output to 00. The number of positrons reaching the detector 402 is substantially constant unless the setting of the processing apparatus 100 or the radiation source 201 is changed when no particles exist in the processing chamber 11. On the other hand, when particles are present in the processing chamber 11, the shape of the potential potential changes because the particles are charged, and the detector 40
The number of positrons reaching 2 changes.

Accordingly, the number of positrons detected when no particles are present in the processing chamber 11 is measured in advance as a reference positron number, and the computer 300 determines that the number of positrons input from the detector 402 is equal to the reference positron number. It is determined whether or not they match within the range of the error.
It is determined whether or not there is a particle in 1. As described above, the occurrence of particles can be detected from the number of positrons that change due to the potential change in the processing chamber 11. During the etching process,
When the presence of particles is detected by the above-described particle detection method, the particles may be discharged out of the processing chamber 11 by the particle removal method described in the first embodiment after the etching process of the semiconductor substrate is completed. In this way, the particles can be removed only when the presence of the particles is detected.
That is, the operation efficiency of the processing system can be improved, and particles can be efficiently removed.

(Fifth Embodiment) Next, a fifth embodiment of the present invention will be described.
The deposit detection method according to the embodiment will be described with reference to the drawings. In this deposit detection method, the presence of a deposit as an impurity on the inner wall of the processing chamber 11 is detected by measuring the Doppler spread of gamma rays emitted when positrons annihilate with electrons. The processing system used in this particle detection method is almost the same as the processing system shown in the second embodiment. However, the processing apparatus 100 has an inside of the processing chamber 11, for example, as schematically shown in FIG. A source 2 substantially the same as the source 200 shown in the second embodiment is provided on a part of the upper electrode 12 for processing.
01 is provided.

The radiation source 201 is a radioactive ion emitting positron.
Positrons are emitted into the processing chamber 11
You. In addition, the radiation source 201 is used as a radioisotope²²N
a, ⁵⁸Co,⁶⁴Cu or the like is provided. Computer
300 is based on the detection result input from the detector 400,
As described later, deposits are formed on the inner wall of the processing chamber 11.
Determine if it exists. Detector 400 is a second real
It is substantially the same as the embodiment.

Next, a method for detecting deposits adhered to the inner wall of the processing chamber 11 using the processing system having the above configuration will be described. The radiation source 201 provided in the processing chamber 11 emits positrons as described above. Then, the detector 400 detects a gamma ray emitted when the positron emitted from the radiation source 201 annihilates with the electron in the processing chamber 11. And the detector 400
Outputs the detection result to the computer 300, and the computer 300 determines whether or not a deposit exists on the inner wall of the processing chamber 11 based on the input detection result. In this embodiment, the Doppler spread of gamma rays shown in the third embodiment is detected.

Since the radiation source 201 is installed in the processing chamber 11 as described above, reaction products generated by processing such as etching also deposit on the radiation source 201. That is, there is a difference in the Doppler spread of gamma rays between the case with and without the deposit. Specifically, when there is no deposit, the positron emitted from the radiation source 201 is irradiated to various places in the processing chamber 11 and annihilates with the electron. On the other hand, if there is a deposit, most of the positrons emitted from the radiation source 201 do not jump out into the processing chamber 11 and disappear with the electrons of the deposit deposited on the radiation source 201.
For this reason, the Doppler spread of gamma rays is smaller in the presence of the deposit than in the absence of the deposit.

Therefore, the Doppler spread of gamma rays emitted when no sediment is present is measured in advance as a reference spread, and the computer 300 detects the Doppler spread.
By comparing the Doppler spread of the gamma ray detected by 0 with the reference spread, it is determined whether or not a deposit exists on the inner wall of the processing chamber 11. As described above, it is possible to detect the presence of a deposit in the processing chamber 11 by installing the radiation source 201 in the processing chamber 11 and measuring the Doppler spread of the gamma ray radiated by the annihilation. it can. If a deposit exists on the inner wall of the processing chamber 11, the deposit is peeled off by opening and closing the transfer port 22 when the semiconductor substrate is transferred, and particles are easily generated. Therefore, when the presence of a deposit is detected by the above-described deposit detection method, the computer 300 may use a display, sound, or the like to warn that particles are likely to be generated.

When the presence of the deposit is detected by the above-described deposit detection method, the particles are removed by the particle removal method described in the first embodiment, or the treatment is performed by cleaning using plasma, a solvent, or the like. The deposit on the inner wall of the chamber 11 may be removed. In this manner, particles and deposits can be removed only when the deposits are present and particles are likely to be generated. That is, the operation efficiency of the processing system can be improved, and particles and deposits can be efficiently removed.

(Sixth Embodiment) Next, a sixth embodiment of the present invention will be described.
The particle removing method according to the embodiment will be described with reference to the drawings. The particle removing method according to the sixth embodiment removes particles as described below by negatively charging the particles. Specifically, by negatively charging the particles, the particles are repelled by the self-bias potential of the negative potential naturally generated on the semiconductor substrate, so that the particles do not reach the semiconductor substrate. In addition,
The self-bias potential is naturally generated in the vicinity of a semiconductor surface due to a difference in the speed of electrons and ions in a plasma device using a high-frequency power supply, and is usually about −200 volts to −300 volts.

As the processing system used in the particle removing method according to the sixth embodiment, for example, the systems and apparatuses shown in FIGS. 1 and 2 can be used. When the system and apparatus shown in FIGS. 1 and 2 are used, the radiation source 200 irradiates particles in the processing apparatus 100 with electrons, negative ions, or both. As a result, the particles are negatively charged. When the negatively charged particles approach the vicinity of the semiconductor substrate as described above, the particles receive a repulsive force due to the self-bias potential naturally generated on the surface of the semiconductor substrate, as shown in FIG. ).
This can prevent particles generated in the processing apparatus 100 from adhering to the semiconductor substrate.

As shown in FIGS. 9 and 10, the processing apparatus 100 includes a dust collecting electrode 31 for collecting negatively charged particles, and a dust collecting electrode 31 for applying a positive voltage to the dust collecting electrode 31. And a power supply 32. 9 is a top view of the configuration of the processing apparatus 100 including the dust collecting electrode 31, and FIG. 10 is a side view of the configuration of the processing apparatus 100 including the dust collecting electrode 31. FIG. Dust collection electrode 31
Is installed on the inner wall of the processing apparatus 100 (processing chamber 11), as shown in FIGS. The material, shape, and the like of the dust collecting electrode 31 are arbitrary as long as there is no problem in processing the semiconductor. However, it must be formed of an electrode material that can apply a sufficient voltage to sufficiently attract negatively charged particles by electrostatic force. The dust-collecting power source 32 is connected to the dust-collecting electrode 31 and applies a positive voltage to the dust-collecting electrode 31 that can sufficiently attract negatively charged particles by electrostatic force.

As shown in FIG. 9 and FIG.
When 0 has a dust collecting electrode 31 and a dust collecting power supply 32, by applying a positive voltage to the dust collecting electrode 31,
As described above, particles that are negatively charged and are repelled by the self-bias potential can be adsorbed to the dust collecting electrode 31. Thereby, it is possible to efficiently prevent the particles from reaching and attaching to the semiconductor substrate. However, the timing of applying the voltage to the dust collecting electrode 31 must be set so as not to adversely affect the processing of the semiconductor. For example, in the case of a plasma device, the timing of applying the potential for dust collection is set immediately before the end of semiconductor processing so that the potential for dust collection does not affect the plasma. As described above, the particles are negatively charged, and the particles are adsorbed by the dust collecting electrodes 31, whereby the particles can be efficiently prevented from adhering to the semiconductor substrate, and the performance of the manufactured semiconductor device can be improved. And reliability can be improved.

(Seventh Embodiment) Next, a seventh embodiment of the present invention will be described.
The particle removing method according to the embodiment will be described with reference to the drawings. The particle removing method according to the seventh embodiment removes particles by negatively charging them, as in the sixth embodiment. However, the particle removing method according to the seventh embodiment is different from the sixth embodiment in the method of negatively charging particles. In the first to sixth embodiments, the particles are irradiated with the charged particles to be negatively charged or electrically neutralized. In the seventh embodiment, particles are negatively charged by the electron current in the bulk plasma.

In the particle removing method according to the seventh embodiment, for example, the processing apparatus 100 and the computer 300 shown in FIG. 1 can be used. In the plasma apparatus (processing apparatus 100), when high-frequency power is applied, that is, when plasma is present, the electron density in the processing chamber 11 is as shown in FIG.
Specifically, in the vicinity of the electrode, that is, in the ion sheath, the electron density is very small, and in the plasma, the ion density is very high. The potential of the plasma generated in the plasma device is as shown on the right side of FIG. 8 (or the right side of FIG. 6).
When the high-frequency power is applied to generate plasma as described above, the particles trapped in the ion sheath are positively charged by the flow of the ion current. Then, the ions are trapped in the ion sheath by the repulsive force from the positive plasma potential. However, when the high-frequency power is gradually reduced, when the high-frequency power becomes equal to or less than a predetermined value, the balance between gravity and electrostatic force is broken, and particles fall from the ion sheath into the plasma due to gravity. The particles that have entered the plasma are negatively charged by the flow of the electron current.

The computer 300 gradually reduces the high frequency power and negatively charges the particles as described above when or immediately before the predetermined processing of the semiconductor is completed according to a program or the like provided in advance. . Thereby, the particles are repelled by the self-bias potential naturally generated on the surface of the semiconductor substrate, and the particles can be prevented from adhering to the semiconductor substrate.
Also, in the seventh embodiment, similarly to the sixth embodiment, the particles that have been repelled by the self-bias potential may be adsorbed by the dust collecting electrode 31 provided on the inner wall of the plasma device. Thereby, it is possible to efficiently prevent the particles from reaching and attaching to the semiconductor substrate. However, the timing of applying the voltage to the dust collecting electrode 31 is set to a timing that does not adversely affect the processing of the semiconductor as described above. As described above, the particles are negatively charged, and the particles are adsorbed by the dust collecting electrodes 31, whereby the particles can be efficiently prevented from adhering to the semiconductor substrate, and the performance of the manufactured semiconductor device can be improved. And reliability can be improved.

In the second, third, and fifth embodiments, when the gamma rays generated in the processing chamber 11 can pass through the wall of the processing chamber 11, a detection window is provided in the processing chamber 11. Instead, the detector 400 may be simply installed near the outside of the processing chamber 11. In the second and third embodiments, after detecting the presence of particles in the processing chamber 11, the processing chamber 11
Instead of continuously irradiating the inside with positrons, electrons or positive or negative ions may be irradiated similarly to the first embodiment.

The acceleration of the positron shown in the fourth embodiment may be performed not between the radiation source 201 but between the processing electrodes. Further, the radiation source 201 shown in the fourth embodiment
Means charged particles other than positrons (eg, electrons and ions)
May be irradiated. Also in this case, the presence of particles can be detected by comparing the number of particles detected by the detector 401 with the previously measured number of reference particles.

In the fifth embodiment, both gamma rays emitted when positrons are emitted from the radiation source 201 and gamma rays emitted when the positrons emitted from the radiation source 201 annihilate with electrons. May be detected, and the positron lifetime may be determined by taking the difference between the detected times. There is a difference in the positron lifetime between the case where the sediment exists and the case where the sediment does not exist. The computer 300 may determine whether or not the deposit exists by calculating the difference between the lifetimes.

The source 201 shown in the fifth embodiment is
It is also possible to use a structure in which a positron from a radioisotope is simply emitted in a certain direction without a parallel plate electrode or the like. Also, instead of the computer 300,
An ASIC (Application Specific IC) storing a predetermined program or the like may be used. Thus, the processing system is controlled by the ASIC, and the processing is automatically performed according to the program. Therefore, it is possible to prevent a malfunction by a person.

The processing system includes a deposit removing device for removing a reaction product deposited on the inner wall of the processing chamber 11, and the particles and the deposits are removed by the processing described in the second to fifth embodiments. When the presence of is found, the deposit removing device may be operated.
Even in this case, since the deposit removing device is operated after the existence of the particles and the deposits becomes clear, the operation efficiency of the processing system can be improved.

The introduction port 17 may be provided at the same height as the mounting position of the semiconductor substrate, and may be formed such that the direction of introduction of the purge gas is parallel or slightly upward to the surface of the semiconductor substrate. With this configuration, the particles are swept away from the semiconductor substrate by the purge gas, so that the particles can be more efficiently prevented from adhering to the semiconductor substrate. In addition, the method of making the particles electrically neutral as described in the first embodiment (1)
(4) may be used in combination with some of them. Each of the methods described in the first to fifth embodiments may be used in combination with some of them. By combining the particle removal system described in the sixth embodiment with the particle removal system described in the first to fifth embodiments, it is possible to more effectively remove particles.
By combining the particle removal system described in the seventh embodiment with the particle removal system described in the first to sixth embodiments, it is possible to more effectively remove particles.

The method described in the first to seventh embodiments is applicable not only to semiconductor substrates but also to any substrate (for example,
(A liquid crystal substrate or the like), and the same effects as described above can be obtained. Note that the system of the present invention does not need to include a dedicated computer, and can be realized by a computer including appropriate peripheral devices. For example, the system of the present invention is realized by recording and distributing a program and data for performing each of the above-described processes to a computer on a recording medium (such as a CD-ROM), installing the program and executing the program on an OS. it can. Further, the method of distributing the program and the data is not limited to the CD-ROM or the like, but may be distributed via a communication line or the like.

[0087]

As is apparent from the above description, according to the present invention, particles generated in the processing chamber can be made electrically neutral. Therefore, the particles are not attracted to the residual charge of the semiconductor substrate or the like subjected to the predetermined processing in the processing chamber, and the particles can be efficiently removed by the gas, thereby producing a product with high performance and high reliability. can do. Further, according to the present invention, the particles can be removed after detecting the presence of the particles. Therefore, the operation efficiency of the processing system can be improved without causing the apparatus for removing particles to operate wastefully.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a configuration of a processing system according to a first embodiment.

FIG. 2 is a schematic diagram illustrating a configuration of a processing device of the processing system of FIG. 1;

FIG. 3 shows a typical operation state of a dry etching process.
It is a figure showing a cycle.

FIG. 4 is a schematic diagram illustrating a configuration of a processing system according to a second embodiment;

FIG. 5 is a conceptual diagram showing a state until a positron is emitted and disappears with an electron.

FIG. 6 is a schematic diagram illustrating a part of a processing apparatus according to a fourth embodiment.

FIG. 7 is a schematic diagram illustrating a part of a processing apparatus according to a fifth embodiment;

FIG. 8 is a schematic diagram illustrating a part of a processing apparatus according to a sixth embodiment.

FIG. 9 is a schematic diagram illustrating a part of a processing apparatus according to a sixth embodiment.

FIG. 10 is a schematic diagram illustrating a part of a processing apparatus according to a sixth embodiment;

FIG. 11 is a diagram illustrating an electron density when plasma exists in a chamber.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Processing chamber 12 Processing upper electrode 13 Processing lower electrode 14 Adsorption plate 15 Gas feed path 16 Exhaust port 17 Inlet 18 Gas outlet 19 High frequency power supply 20 Insulating plate 21 DC power supply 23 Irradiation port 31 Dust collection electrode 32 Dust collection electrode Power supply 100 Processing unit 200 Radiation source 201 Radiation source 300 Computer 400 Detector 401 Detector 402 Detector

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[Procedure amendment]

[Submission date] February 3, 2000 (200.2.3)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0030

[Correction method] Change

[Correction contents]

Particles according to the first aspect of the present invention
Removal system, impurity detection system according to the second aspect of the present invention
Delivery system and a partition according to the third aspect of the present invention.
And at least one of the vehicle detection systems.
You may.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0033

[Correction method] Change

[Correction contents]

Particles according to the first aspect of the present invention
Removal system, impurity detection system according to the second aspect of the present invention
Delivery system, particles according to a third aspect of the present invention
A detection system and a parser according to a ninth aspect of the present invention
At least one of the tickle removal systems
You may get.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 21/66 H01L 21/66 Z

Claims (31)

[Claims] 1. A particle removal system for removing particles generated when a predetermined process is performed in a processing chamber, wherein the processing chamber irradiates particles having a positive or negative charge to the inside of the processing chamber. Irradiating means for electrically neutralizing the particles present in the particles; and, after irradiating the particles with the irradiating means, introducing a gas into the processing chamber to suck and remove the electrically neutral particles. A particle removing system, comprising: a removing unit. 2. The particle removing system according to claim 1, wherein said irradiating means irradiates at least one of positrons, electrons, positive ions, and negative ions as said particles. 3. An impurity detection system for detecting the presence of impurities generated when a predetermined process is performed in a processing chamber, wherein the positron emitted from a radioactive isotope is irradiated into the processing chamber. Means, a first detecting means for detecting a gamma ray generated by pair annihilation of the positron and an electron in the processing chamber, and, based on a detection result of the detecting means, whether or not an impurity is present in the processing chamber. And a determination means for determining whether or not the impurities are detected. 4. The apparatus according to claim 1, further comprising a second detector for detecting a gamma ray emitted when the positron is emitted from the radioisotope, wherein the discriminator is the first detector and the second detector. 4. The impurity detection system according to claim 3, wherein a life of the positron is obtained from the detection result, and it is determined whether or not an impurity is present in the processing chamber. 5. The determination means obtains a Doppler spread of energy of the gamma ray from a detection result of the first detection means, and determines whether or not the obtained Doppler spread matches a reference Doppler spread. 4. The impurity detection system according to claim 3, wherein whether or not an impurity is present in the processing chamber is determined. 6. Irradiating means for irradiating particles having a positive or negative charge into the processing chamber to electrically neutralize impurities present in the processing chamber; and irradiating the particles by the irradiating means. And a removing unit for introducing a gas into the processing chamber to remove electrically neutral impurities, and the determining unit determines that the impurities exist in the processing chamber. In the case, the irradiation unit irradiates the particles, and after the irradiation of the particles by the irradiation unit, the removal unit removes impurities. The method according to claim 3, wherein: Impurity detection system. 7. The method according to claim 1, wherein the determining means includes, as the impurity, particles floating in the processing chamber;
7. The impurity detection system according to claim 3, wherein it is determined whether at least one of the deposits attached to the inner wall of the processing chamber exists. 8. 8. A particle detection system for detecting the presence of particles generated when a predetermined process is performed in a processing chamber, wherein the particle detection system is installed in the processing chamber and emits particles having a positive or negative charge. A counting means for counting the number of particles flying out of particles emitted from the emitting means, which is provided in the processing chamber at a position opposed to the emitting means, and counting by the counting means. A determination unit configured to determine whether a difference between the number of particles and a reference number of particles matches within a predetermined range, and determine that the two do not match, and determine that particles are present in the processing chamber; A particle detection system comprising: 9. The radiating means includes a positron as the particle,
The particle detection system according to claim 8, wherein the particle emission system emits at least one of electrons, positive ions, and negative ions. 10. Irradiating means for irradiating particles having a positive or negative charge into said processing chamber to electrically neutralize particles present in said processing chamber; and after irradiating the particles by said irradiating means. Removing means for introducing a gas into the processing chamber and sucking and removing electrically neutral particles, wherein the determining means determines that particles are present in the processing chamber. The particle detection system according to claim 8, wherein the irradiation unit irradiates the particles, and the irradiation unit removes the particles after the irradiation of the particles by the irradiation unit. 11. A particle removing method for removing particles generated when performing a predetermined process in a processing chamber, wherein the processing chamber is irradiated with particles having a positive or negative charge. An irradiation step for electrically neutralizing the particles present in the particles, and after irradiating the particles in the irradiation step, introducing a gas into the processing chamber, and suctioning and removing the electrically neutral particles. A particle removing method, comprising: a removing step. 12. The method according to claim 11, wherein the irradiating step includes a step of irradiating at least one of positrons, electrons, positive ions, and negative ions as the particles. . 13. A method for detecting the presence of impurities generated when performing a predetermined process in a processing chamber, the method comprising irradiating a positron emitted from a radioisotope into the processing chamber. A first detection step of detecting a gamma ray generated by pair annihilation of the positron and an electron in the processing chamber; and, based on a detection result of the detection step, whether particles are present in the processing chamber. And a determining step of determining the impurity. 14. The method according to claim 1, further comprising a second detecting step of detecting a gamma ray emitted when the positron is emitted from the radioisotope, wherein the discriminating step includes the first detecting step and the second detecting step. The method for detecting an impurity according to claim 13, further comprising: determining a lifetime of a positron from a detection result to determine whether or not an impurity exists in the processing chamber. 15. The determining step determines Doppler spread of energy of the gamma ray from the detection result of the first detecting step, and determines whether the calculated Doppler spread matches a reference Doppler spread. 14. The method according to claim 13, further comprising the step of determining whether an impurity is present in the processing chamber. 16. An irradiation step of irradiating particles having a positive or negative charge into the processing chamber to make particles existing in the processing chamber electrically neutral, and after irradiating the particles in the irradiation step. A removing step of introducing a gas into the processing chamber to suck and remove electrically neutral particles, and determining that the particles are present in the processing chamber in the determining step. In this case, the method further comprises a step of irradiating the particles in the irradiation step, and after irradiating the particles in the irradiation step, sucking and removing impurities in the removing step. 2. The method for detecting impurities according to claim 1. 17. The method according to claim 17, wherein the determining step includes:
17. The method according to claim 13, further comprising a step of determining whether at least one of particles floating in the processing chamber and deposits adhering to the inner wall of the processing chamber exists. The method for detecting impurities according to any one of the above items. 18. A particle detection method for detecting the presence of particles generated when a predetermined process is performed in a processing chamber, the method comprising: radiating particles having a positive or negative charge, which are installed in the processing chamber. And a counting step of counting the number of flying particles out of the particles emitted in the emitting step at a position opposite to a position where the particles in the processing chamber are emitted. A step of determining whether the difference between the counted number of particles and the reference number of particles matches within a predetermined range, and determining that the particles do not exist in the processing chamber when determining that they do not match; A particle detection method, comprising: 19. The particle detecting method according to claim 18, wherein said radiating step includes a step of radiating at least one of positrons, electrons, positive ions, and negative ions as said particles. 20. An irradiation step of irradiating particles having a positive or negative charge into the processing chamber to make particles existing in the processing chamber electrically neutral, and after irradiating the particles in the irradiation step. A removing step of introducing a gas into the processing chamber to suck and remove electrically neutral particles, and determining that the particles are present in the processing chamber in the determining step. 19. The method according to claim 18, further comprising: irradiating the particles in the irradiating step, and after irradiating the particles in the irradiating step, suctioning and removing the particles in the removing step. Method. 21. An irradiation means for controlling a radiation source to irradiate a particle having a positive or negative charge into a processing chamber to electrically neutralize particles present in the processing chamber. Gas irradiation means for controlling a gas source to introduce gas into the processing chamber after irradiation of the particles by the irradiation means, and controlling a vacuum pump together with the gas introduced into the processing chamber by the gas introduction means. A computer-readable recording medium storing a program for causing the apparatus to function as a particle removal system, comprising: a removal unit configured to suction and remove electrically neutral particles. 22. A computer, comprising: an irradiating means for controlling a radiation source to irradiate a positron into the processing chamber; and controlling a detector so that the positron irradiated by the irradiating means is present in the processing chamber. A detection unit configured to detect gamma rays emitted by annihilation with electrons; and a determination unit configured to determine whether particles are present in the processing chamber based on a detection result of the detection unit. A computer-readable recording medium on which a program for functioning as a computer is recorded. 23. A particle removal system for removing particles generated when performing a predetermined process in a processing chamber, comprising irradiating the processing chamber with particles having a negative charge;
A particle removing system, comprising: irradiation means for negatively charging particles existing in the processing chamber. 24. The particle removing system according to claim 23, wherein said irradiating means irradiates at least one of electrons and negative ions as said particles. 25. The irradiating means for irradiating the particles with the particles so as to give a charge which is repelled by a negative self-bias potential naturally generated in the processing chamber to particles in the processing chamber. The particle removal system according to claim 23, wherein: 26. An electrode for adsorbing the negatively charged particles, and voltage applying means for applying a positive voltage to the electrode to adsorb the negatively charged particles to the electrode. The particle removal system according to any one of claims 23 to 25, comprising: 27. A particle removal system according to claim 1 or 2, an impurity detection system according to claim 3 to 7, and a particle detection system according to claim 8 to 10. The method for removing particles according to claims 11 to 12, the method for detecting impurities according to claims 13 to 17, the method for detecting particles according to claims 18 to 20, and the claim. The recording medium according to any one of claims 21 to 22, further comprising at least one of the recording media recorded thereon, for removing particles.
The particle removal system according to any one of the above. 28. A particle removing system for removing particles generated when performing a predetermined process in a processing chamber, wherein the high-frequency power is gradually reduced when the high-frequency power is turned off, so that the high-frequency power is reduced in the bulk plasma. A particle removing system, comprising: charging means for causing particles to be incident and negatively charging the particles by an electron current of plasma. 29. The charging means, by gradually lowering the high-frequency power, gives a charge which is repelled by a negative self-bias potential naturally generated in the processing chamber to particles in the processing chamber. The particle removal system according to claim 28, wherein: 30. An electrode for adsorbing the negatively charged particles, and voltage applying means for applying a positive voltage to the electrode to adsorb the negatively charged particles to the electrode. 30. The particle removal system according to claim 28 or claim 29. 31. A particle removal system according to claim 1, 2 or 3, an impurity detection system according to claim 3 to 7, and a particle detection system according to claim 8 to 10. The particle removal method according to any one of claims 11 to 12, the impurity detection method according to claims 13 to 17, the particle detection method according to claims 18 to 20, and the particle detection method. 28. The recording medium according to claim 19, further comprising at least one of a recording medium recorded according to claim 22 and a particle removal system according to claim 23 to claim 27, wherein the particles are removed. 31. The particle removal system according to any one of 28 to 30.