JP2001259555A - Dry ice snow-cleaning method and apparatus using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dry ice snow-cleaning method and apparatus having convenience capable of cleaning an object to be cleaned even at any place with good cleaning efficiency without charging the object or generating dew condensation on the object. SOLUTION: Dry ice snow TS, which is formed by expanding pressurized liquefied carbon dioxide TL by a throttle mechanism 5, is ejected to the object to be cleaned from a jet orifice 8d to clean the object. In this method, gas G is ejected to the peripheral part of the jet stream of dry ice snow TS in parallel to the jet stream and the length of a flow pipeline 7 from the throttle mechanism 5 to the jet orifice 8d is adjusted to eject dry ice snow TS to clean the object.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning method and a cleaning apparatus using snow-like dry ice (hereinafter referred to as "dry ice snow"), for example, a recycled part of a copying machine, a semiconductor wafer, a semiconductor inspection apparatus and a cleaning apparatus. Its components, electrical board, MR head (disk reader),
In order to remove impurities and contaminants such as organic substances, acids, hydrocarbons and particles attached to burrs of plastic molding and precision parts, etc., a method of cleaning by spraying dry ice snow on them and cleaning used in the cleaning method. It concerns the device.

[0002]

2. Description of the Related Art An apparatus for cleaning various objects to be cleaned using dry ice snow is disclosed in Japanese Utility Model Laid-Open No. 3-7984, a microfilm. This causes adiabatic expansion of liquefied carbon dioxide gas to generate dry ice snow,
This dry ice snow is sprayed onto the surface to be cleaned to remove organic substances, acids, hydrocarbons and other impurities on the surface to be cleaned. In this apparatus, the needle valve of the throttle mechanism is located near the cleaning nozzle (or jet port) and has little cleaning power (problem of cleaning power).

In addition, since liquefied carbon dioxide has a temperature of about -80 ° C., in the cleaning by the above-mentioned cleaning apparatus, when the cleaning is performed continuously, the temperature of the cleaning object decreases as the temperature of the cleaning atmosphere decreases. As a result, the moisture in the air condenses and adheres to the object to be cleaned, and the object to be cleaned cannot be used due to oxidation or the like. Therefore,
As shown in the microfilm of No.7984,
It was necessary to take measures on the cleaning object side, such as controlling the temperature of the cleaning object on the cleaning object side. That is, some kind of temperature control equipment or the like is required on the side of the object to be cleaned, the place where the cleaning operation is performed is restricted, and the cleaning operation cannot be appropriately performed anywhere. problem).

Further, as shown in the microfilm of Japanese Utility Model Application Laid-Open No. 5-49258, a system for generating dry ice snow and a system for generating nitrogen gas are separately provided in the injection gun, and the injection gun has two components. Since it has a structure in which two systems are arranged, there is a problem in operability in performing the cleaning work (workability problem).

Further, since dry ice snow used for cleaning and gas used for jetting are dry, when these fluids flow through pipes and the like, static electricity is easily generated due to friction with the pipes. In particular, dry ice snow may be charged up to 20,000 V. For example, when the dry ice snow is used for cleaning, especially when the object to be cleaned is a precision semiconductor component such as an IC, breakage may occur. There was a problem such as being caused (problem of static electricity).

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned inconveniences and problems. Even when snow-like dry ice is used, the length of the pipeline on the downstream side of the throttle mechanism is reduced. By adjusting it, it has sufficient physical cleaning power, and in addition to the problem of low temperature of the object to be cleaned, it eliminates the problem of low temperature without directly controlling the temperature of the object to be cleaned, and continuously In the case of cleaning, it is possible to eliminate the generated static electricity without causing dew condensation and when the object to be cleaned is charged, especially when there is a possibility that damage may occur.In addition, in any case, An object of the present invention is to make it possible to reliably clean an object to be cleaned. Another object of the present invention is to improve the operability in using a cleaning nozzle for jetting dry ice snow. Furthermore, when cleaning the object to be cleaned, there is no need to prepare a special device or the like on the side of the object to be cleaned, and there is the convenience that cleaning can be performed at any place as long as there is a dry ice snow generating device. It is an object of the present invention to provide a cleaning method and a cleaning device for performing the method.

[0007]

According to a first aspect of the present invention, a dry ice snow formed by expanding pressurized liquefied carbon dioxide gas by a throttle mechanism is applied to an object to be cleaned from a jet port. This is a method of washing the dry ice snow by injecting the gas for injection in parallel with the periphery of the jet flow of dry ice snow, and adjusting the length of the flow pipe from the throttle mechanism to the jet outlet. The dry ice snow cleaning method is characterized in that the object to be cleaned is washed by spraying dry ice snow.

According to a second aspect of the present invention, there is provided a liquefied carbon dioxide gas container for storing liquefied carbon dioxide gas, and a liquefied carbon dioxide gas container connected to the liquefied carbon dioxide gas container for injecting dry ice snow through a throttle mechanism for adiabatic expansion. A dry ice snow supply system comprising a flow channel leading to the washing nozzle, and a flow channel leading to a jet gas injection port provided on the outer peripheral portion of the cleaning nozzle in connection with the jet gas source container. A dry ice snow cleaning device from a gas supply system for injection comprising:
The dry ice snow supply system is provided with a pipe length adjusting mechanism for adjusting a flow pipe length from the throttle mechanism to the cleaning nozzle, and is provided on an outer peripheral portion of the cleaning nozzle of the injection gas supply system. The dry ice snow cleaning apparatus is characterized in that the injection port is an injection port for injecting in parallel with the injection direction of dry ice snow.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 and FIG.
This will be described with reference to FIG. Figure 1 shows the dry ice of the present invention.
FIG. 2 is a schematic system diagram illustrating an example of a no-cleaning device, and FIG.
Is a distribution pipe used in the dry ice snow apparatus of the present invention.
It is a system schematic diagram showing an example of a length adjustment mechanism. Figure 1
The dry ice snow cleaning apparatus 10 of the present invention
Carbon dioxide gas T _LFrom the liquefied carbon dioxide container 1 for storing
Carbon dioxide gas T_LDry ice snow T _SGenerated and cleaned
Dry ice / snow supply system 9 for supplying slur 8
Dry ice snow T spouted from the washing nozzle 8
_SHigh pressure gas such as nitrogen gas to promote
Gas source container 1 filled with an injection gas source consisting of
Inject the gas for injection into the washing nozzle 8 from the dry eye
Snow Snow T_SJets provided along the outer circumference of the jet port 8d
Injection gas supply system connected so as to communicate with the outlet 8g
And 18.

In the dry ice / snow supply system 9, the liquefied carbon dioxide gas container 1 is connected to the opening / closing means 3 such as an electromagnetic valve for controlling the supply of the liquefied carbon dioxide gas _TL via a pipe 2, and then to the pipe 4. It provided continuously liquefied carbon dioxide T _L to the needle valve and such stop mechanism 5 orifices for the dry ice snow T _S via the further the narrowed mechanism 5 pipe 6
Is connected to a connecting tool 21 disposed on the wall of the control box 20 via the. A flow conduit 7 composed of a concentric double pipe composed of a flexible central pipe 7a and an outer pipe 7b is connected to the connecting tool 21, and the pipe 6 is arranged so as to communicate with the central pipe 7a. ing. Further, a washing nozzle 8 having a central ejection pipe 8a disposed substantially at the center for ejecting the dry ice snow T _S is provided at the tip of the distribution pipe 7.
The center pipe 7a and the center ejection pipe 8a are connected so as to communicate with each other.

On the other hand, the injection gas supply system 18 includes an injection gas source container 11, which is a container filled with a high-pressure injection gas G such as nitrogen gas to promote the injection of dry ice snow T _S , The line 12 is connected to the on-off valve 13 and the pressure regulator 14 and is connected to the ionizing means 16 via the line 15, and the ionizing means 16 is further connected to the line 17.
Is connected to the connecting tool 21 via the. Incidentally, the ionization means 16 for injecting gas G is ionized, it is charged with dry ice snow T _S intended for discharge upon ejection. A cleaning nozzle connected to the connecting tool 21 so as to communicate with the flow path 7c of the outer pipe 7b of the communication pipe 7 and further connected to the end of the communication pipe 7 8 is connected so as to communicate with a flow path 8c in an outer pipe 8b, and communicates with an injection port 8g arranged along the outer periphery of a discharge port 8d of a central discharge pipe 8a for discharging the dry ice snow T _S. ing.

The injection gas supply system 18 including the above-mentioned ionization means 16 is provided with a heating control means 19 for heating the injection gas G to a constant temperature.
Then, the heated jetting gas G is projected onto the object to be cleaned from the cleaning nozzle 8 so as to prevent the temperature of the object to be cleaned from lowering, thereby preventing dew condensation on the surface of the object to be cleaned. If the heating control means 19, the opening / closing means 3 of the dry ice snow supply system 9 and the throttle mechanism 5 are collectively housed in a control box 20, the liquefied carbon dioxide gas container 1 and the liquefied carbon dioxide gas container 1 By connecting the piping of the gas source container 11 for dry ice snow cleaning equipment immediately,
A cleaning operation can be performed.

Further, in the dry ice snow cleaning apparatus of the present invention, the connecting pipe 21 and the cleaning nozzle 8 are connected to each other through the flow pipe 7 as shown in FIG.
2 and 7-3, and comprises a circulation pipe length adjusting mechanism 25 for adjusting the length of the pipe through which the dry ice snow T _S flows by appropriately operating the valves V1, V2 and V3. I have. That is, FIG. 2 is a system schematic diagram showing an example of a distribution pipe length adjusting mechanism used in the dry ice cleaning device of the present invention. In FIG. 2, the same reference numerals as those shown in FIG. Yes, detailed description is omitted.

In FIG. 2, a distribution pipe length adjusting mechanism 25 according to the present invention has a distribution pipe 22 connected to a connector 21 and branched from the distribution pipe 22 so as to have different lengths. 1, 7-2, 7-3, ------ are provided in plurality, and each of the distribution lines 7-1, 7-2, 7-3, ------ is provided with a valve V1. , V2, V3,..., Respectively, to the cleaning nozzles 8-1, 8-2, 8-3,. Then, one of the valves V1, V2, V3, ------ is appropriately selected and opened, whereby the dry ice snow T _S circulates,
Dry ice snow T _S is supplied to the washing nozzle 8 through a flow pipe of a specified length and is ejected.

As described above, the dry ice cleaning apparatus of the present invention can be operated by opening one of the valves V1, V2, V3,. Is adjusted to cause the dry ice snow T _S to be jetted, so that the dry ice snow TS can be selected and jetted in an appropriate jetting state according to the degree of contamination of the object to be cleaned. Further, the valves V1, V2, V
3. Open some of ------ and set the desired length among the distribution pipes 7-1, 7-2, 7-3, ------ with different distribution pipe lengths. Washing nozzles 8-1, 8- so that dry ice snow T _S is ejected using a plurality of distribution pipes having the same distribution pipe length.
2, 8-3, ------ are arranged, these are fixedly arranged as washing lines, for example, in order to cope with a large amount of washing processing, and an object to be washed is automatically fed to this washing line. By setting the position to be cleaned to be a different specific position in accordance with the different lengths of the circulation pipes, it is possible to clean a large number of objects to be cleaned in a short time.

It is convenient to operate the valves V1, V2, V3,... Using a group of valves such as a rotation switching valve. In addition, the circulation pipes 7-1 and 7- having different lengths described above.
2, 7-3, ------ have the same structure as the distribution pipe 7 described in FIG. 1, and surround the central pipe 7a through which the dry ice snow T _S flows, and the central pipe 7a. And an outer tube 7b coaxially arranged with the outer tube 7b and surrounding the center tube 7a.
A flow path 7c through which the injection gas G flows is formed therein.

Further, the cleaning nozzles 8-1, 8-2, 8-3, ----
Also in the structure of-, an outer tube 8b is disposed coaxially with the center ejection tube 8a as in FIG. 1 described above, and the outer tube 8b has an injection gas along the outer periphery of the center ejection tube 8a. G channel 8c
Is formed at the tip of the dry ice snow spout 8
It communicates with the injection port 8g of the injection gas arranged along the outer periphery of d. And the injection port 8g of the injection gas G is:
It is configured to form a flow parallel to the jet flow of dry ice snow T _S jetted from the jet port 8d of dry ice snow. The results projection and cooperating combined and cleaning effect of the dry ice snow T _S to the object to be cleaned can be performed more effectively.

[0018]

Next, as an example, a cleaning method using the above-described dry ice snow cleaning apparatus of the present invention will be described. The liquefied carbon dioxide gas T _S is led out of the liquefied carbon dioxide gas container 1 through the pipe 2 at a pressure of about 6 MPa, and is continuously supplied to the expansion mechanism 5 with the opening / closing means 3 opened. And is adiabatically expanded in the narrowed mechanism 5 produces a dry ice Sno -T _S and. Then dry ice snow T _S that is the generated led to connector 21 via line 6, followed by dry ice snow T _S is different distribution line 7 of the pipe length from the distribution pipe 22 as shown in FIG. 2 -1, 7-2, 7-3, ------ flow into the central pipe 7a. The valves V1, V
2. According to the open state of V3, at least one of the flow lines 7-1, 7-2, 7-3, ------ in which these valves are open.
Is introduced into at least one of the washing nozzles 8-1, 8-2, 8-3 ----- passing through the central pipe 7a of the two conduits, and is spouted through the central jet pipe 8a. Dry ice snow T _S is jetted toward the object to be cleaned.

On the other hand, at the same time, a jetting gas G made of dried nitrogen gas having a low dew point is led out from the jetting gas source container 11 via the pipe line 12 and passed through the on-off valve 13 to the pressure regulator 14. The pressure is adjusted to a constant pressure of about 0.2 MPa
5 is introduced into the ionization means 16. After being ionized by the ionizing means 16, the injection gas G flows into the connecting tool 21 via the pipe line 17, and then reaches the distribution pipe 22 shown in FIG. Then, the injection gas G flows through the distribution pipes 7-1 and 7-2 having different pipe lengths from the distribution pipe 22 shown in FIG.
7-3, ----- flows into the flow path 7c in the outer pipe 7b. And, valves V1, V2, V3 arranged in each distribution pipeline, -----
According to the open state of (-), the flow path 7c in the outer pipe 7b of at least one of the flow paths 7-1, 7-2, 7-3, ------ in which these valves are open. Cleaning nozzle 8 that passes through it
-1, 8-2, 8-3 ----- are introduced into at least one cleaning nozzle. And it is injected in the flow that is parallel to the jet stream of dry ice snow T _S toward the object to be cleaned from the ejection outlet 8g of the injection gas G through the flow path 8c of the outer tube 8b.

During this time, the pressure of the injection gas G from the injection gas source container 11 is adjusted to about 0.2 MPa by the pressure regulator 14, and then the heating control means 19 heats the injection gas G to a temperature of 50 to 90 ° C. And supplied to the cleaning nozzle 8. Then, the object to be cleaned injecting gas heated dry ice Sno -T _S is G is injected. Since the cleaning nozzle 8 to be washed are very close, the injection gas G dry ice Sno -T _S will not be sublimated be hot. As a result, by heating the jetting gas G, the object to be cleaned is less likely to have a low temperature and is less likely to form dew, so that cleaning can be performed efficiently. Also, by using a drying (low dew point) gas as the gas for spraying, the object to be cleaned can be maintained in a dry state, and dew condensation on the object to be cleaned can be more effectively prevented. It is particularly effective to perform the cleaning process in a short time. It should be noted that the heating control means 19 is specifically composed of a heater, a sensor, and a controller thereof, so that more effective heating temperature increase control can be performed.

The injection gas G is ionized by the ionization means 16 so that when the fluid flows through the pipeline, the charge generated by friction with the pipeline can be eliminated. In particular, the dry ice snow T _S exerts an enormous effect in preventing the dry ice snow from agglomerating due to the electrification of the dry ice snow T _S , thereby damaging the object to be cleaned. In particular, when the object to be cleaned is likely to be damaged by electricity such as a semiconductor chip, removing the charged static electricity is very effective for preventing damage. Ionization means 16, only the injection gas G not limited to be used to ionize may be disposed directly dry ice Sno -T _S to ionize,
If it is provided in any one of the supply systems, the effect is sufficiently exhibited.

The ionization means 16 may be of various types. For example, in the case where a system is used in which an electrode is arranged in a pipe to generate plasma and a fluid flowing through the pipe is ionized, a dry ice snow T when attaching the electrode to the supply system 9 of _S, dry ice Sno -T _S is attached to the electrode, it is deposited, also becomes a cause of clogging, in this case a dry ice Sno - not attached to the supply system 9, the injection gas supply system 1
8 is more preferable. As described above, it is only necessary to examine a system to be appropriately installed depending on the type of the ionization means and to study ionization of the atmosphere. In addition, other ionization means 1
As 6, a type such as a plasma discharge type or a soft X-ray type can be used. Also, an ionizer or the like can be used. These are not limited to the above members, and may be selected as appropriate.

As the gas used for the injection gas, nitrogen gas, carbon dioxide gas, dry air or the like can be used. These gases may be supplied from a high-pressure gas container, or when dry air is used, a compressor or the like may be used. The liquefied carbon dioxide container may use a so-called cylinder or a large-sized vacuum insulated container which is composed of an inner and outer container made of metal and is filled with liquefied carbon dioxide in a vacuum insulated container having a vacuum layer between the inner and outer containers. You may.

Next, the following experiment was conducted to confirm the effects of the dry ice snow cleaning method of the present invention. [Experiment 1] As an experiment 1, using the dry ice snow-cleaning apparatus of the present invention having the system shown in FIG. , Resin pieces, solder debris, aluminum, silicon, copper, etc. were removed and washed. A fixed orifice is used as the throttle mechanism 5 of the apparatus of the present invention, a heater and a PID (proportional / integral / differential) controller are used as the heating control means 19, and a plasma discharge method is used as the ionization means 16. installed.

The length of the flow pipe from the downstream side of the throttle mechanism 5 of the dry ice snow supply system 9 to the washing nozzle 8 is set to 5
The flow pipe 7 was selected using the flow pipe adjusting mechanism 25 of FIG. 2 so as to be 00 mm, and was fixed using a center pipe 7a made of Teflon (registered trademark) as a material of the pipe. The conditions and contents of the experiment are as follows. <Experimental conditions> Injection gas G: A nitrogen gas having a nominal dew point of -65 ° C was used as a high-pressure gas (supply pressure: 0.2 MPa to 0.78 MPa).
a, room temperature, flow rate: 65 NL / min) Liquefied carbon dioxide _TL : (supply pressure: about 6 MPa, room temperature) Ambient temperature: room temperature

<Experiment Details> The experiment was performed on the Lyice Snow T
Set the _S supply time of 2.0 seconds, continuously dry ice Sno -T _S allowed jetted from jetting port 8d of the washing nozzle 8, whereas the 0.2MPa nitrogen gas as the injection gas G heating control means 19, the temperature was adjusted to 60 ° C., and the liquid was continuously jetted from the jet port 8 g of the washing nozzle 8. Then, in this state, the state of occurrence of dew condensation on the probe card and the state of removal of attached solder chips were confirmed. Then, as a one-step process, the above-described state check is performed by [Inspection 1], the state is checked by a two-step process that repeats similar processing [Inspection 2], and further one-step processing is added.
Inspection was performed for three processes, such as confirmation of the state by stage processing [Inspection 3]. Table 1 shows the results of the experiment. The state of removal of solder debris was confirmed by contact resistance, and a value of 0.5 or less was accepted. In addition, regarding the dew condensation, even if the generated water droplets subsequently evaporate, they remain as stains. Therefore, the presence or absence of dew condensation was visually confirmed.

[0027]

[Table 1]

First, in the inspection 1, no dew condensation was observed on the probe card to be processed. And
It was confirmed that the removal state of the solder debris was about 90% (partially, the contact resistance was larger than 0.5). Inspection 2
No dew condensation was observed on the probe card to be processed. In the state of removal of the solder debris, traces of the solder debris were observed in one place (one place, the contact resistance was larger than 0.5). Further, in Inspection 3, no dew condensation was observed on the probe card to be processed. Then, it was confirmed that no solder debris was recognized at all and the solder was completely removed (contact resistance <0.5), and it was confirmed that the cleaning was performed well. The injection gas G
By changing the injection pressure according to the type of the deposit, the degree of contamination, and the strength of the deposit, the cleaning power can be changed to a corresponding detergency.

[Experiment 2] Next, as Experiment 2, the aperture mechanism 5
Further, the distribution pipe length up to the washing nozzle 8 is set to 45, 200, 5
The cleaning effect when changing to 00, 1000, 1500, and 2000 mm was confirmed. The setting of the circulation pipe length is performed by the circulation pipe length adjusting mechanism 25 shown in FIG.
1, 7-2, 7-3, ----- The pipes are arranged so that the pipe lengths match them, and the pipes are made of flexible stainless steel material. 7a, valves V-1, V-2, V-3,-
---- Switching was performed. As an object to be cleaned,
Oil attached to the burn-in board using a burn-in board, resin pieces, solder chips, aluminum, silicon,
Removal of copper and the like was performed.

The conditions of the experiment are the same as in Experiment 1 and are as follows. <Experimental conditions> Injection gas G: A nitrogen gas having a nominal dew point of -65 ° C was used as a high-pressure gas (supply pressure: 0.2 MPa to 0.78 MPa).
a, room temperature, flow rate: 65 NL / min) Liquefied carbon dioxide _TL : (supply pressure: about 6 MPa, room temperature) Ambient temperature: room temperature

<Experiment Details> The experiment was performed on the Lyice Snow T
Set the _S supply time of 2.0 seconds, continuously dry ice Sno -T _S allowed jetted from jetting port 8d of the washing nozzle 8, whereas the 0.2MPa nitrogen gas as the injection gas G heating control means 19, the temperature was adjusted to 60 ° C., and the liquid was continuously jetted from the jet port 8 g of the washing nozzle 8. Then, in this state, the cleaning state of the burn-in board, which is the object to be washed, is checked by the difference in the length of the circulation pipe, and the object is sprayed on the object to be washed
It was confirmed pressure (MPa) of dry ice Sno -T _S. The results are shown in Table 2. The spraying pressure was measured using a pressure measurement film (trade name: Fuji Prescale, manufactured by Fuji Film Co., Ltd.).

[0032]

[Table 2]

From the results of Experiment 2, the dryer of the present invention was
Issuno-T_SSqueezing mechanism 5 in the cleaning device by
The length of the circulation pipe from the cleaning nozzle 8 to the
00mm, 1000mm, 1500mm, 2000mm
And dry ice snow-T _SContinuously and simultaneously
By continuously flowing the injection gas G to the object to be cleaned
Even adhered metal can be removed, and condensation
It was confirmed that there was no generation. Obedience
Therefore, the length of the downstream circulation pipe of the throttle mechanism 5 depends on the object to be cleaned.
It depends, but if it is 200mm or more, it is effective enough
Was confirmed. Also, depending on the material of the pipe, especially the center pipe 7a
The difference in cleaning power is recognized, and Teflon is better than stainless steel
It was confirmed that the material made of stainless steel could improve the detergency.
Was. In addition, it was confirmed that the cleaning power increased as the flow rate increased.
Came.

Further, it was confirmed that the length of the flow conduit from the squeezing mechanism 5 to the cleaning nozzle 8 was increased, and the pressure at the time of cleaning measured with a pressure measurement film was increased.
From this, by adjusting the length of the flow conduit according to the adhesion state of the object to be removed and the pressure resistance of the object to be cleaned, it is possible to perform an appropriate cleaning process and improve the cleaning efficiency. Was confirmed.

In the above experiment, the object to be cleaned was not placed in a closed space. However, depending on the environment to be cleaned, the object to be cleaned was made into a closed space such as a glove box, and sublimated carbon dioxide gas and injection gas were used. By slowly pulling with a blower, the ionized fluid can be held in the closed space, and the charge can be removed more efficiently. In addition, in order to collect oil, solder debris, resin chips, aluminum, copper, etc., removed during cleaning,
The cleaning may be performed in a substantially closed space, and the cleaning may be performed by exhausting air from a part of the substantially closed space.

Further, in a place where cleanliness is a problem in cleaning, cleaning can be performed without polluting the environment by performing cleaning in a clean bench or a draft chamber equipped with a filter such as an HEPA filter. Further, a cleaning nozzle and a distribution pipe for mounting the same are composed of a central jet pipe 8a of the dry ice snow T _S as shown in FIG. 3 and an outer pipe 8b disposed coaxially therearound. A washing nozzle 28 having a triple pipe structure in which an exhaust pipe 28b is disposed coaxially so as to further cover the outermost side of the heavy pipe, and a flow path 2 formed in the outermost exhaust pipe 28b
By suctioning from 8C, the removed matter removed by the washing is collected and sucked by the dust collecting hood 29 arranged at the tip of the washing nozzle 28, so that it can be removed at the same time as washing.

The outer pipe 7b is arranged coaxially with the outside of the center pipe 7a so that the flexible flow pipe 27 for mounting the washing nozzle 28 can be aligned with the pipe of the washing nozzle 28. And an exhaust pipe 27, which is the outermost pipe coaxially outside thereof.
Needless to say, the distribution pipe 27 has a triple pipe structure in which b is disposed.

In each of the above experiments, the object to be cleaned was a recycled part of a copying machine, a semiconductor wafer, a semiconductor inspection apparatus and its parts, an electric board,
Although the R head, plastic molded burrs and precision parts have been exemplified, the present invention is not limited to these articles, and can be applied to washing of foods such as fruits such as melons, tangerines and watermelons, and vegetables. Of course, you can.

[0039]

The method and apparatus for cleaning dry ice snow according to the present invention are implemented in the above-described embodiment, and have the following effects. The dry ice snow cleaning apparatus of the present invention has a dry ice snow circulation pipe length of 200 mm, 500 mm, 1 mm from the squeezing mechanism to the cleaning nozzle.
000mm, 1500mm, 2000mm, by continuously injecting dry ice snow and continuously injecting separate gas, it is possible to remove even the metal adhering to the object to be cleaned and generate dew It was confirmed that washing could be performed without causing the washing. Therefore, it was confirmed that the length of the flow conduit reaching the cleaning nozzle on the downstream side of the squeezing mechanism depends on the object to be cleaned.

Further, it was confirmed that the length of the flow conduit from the throttle mechanism to the cleaning nozzle was increased and the pressure during cleaning was increased. Therefore, by adjusting the length of the flow conduit according to the adhesion state of the object to be removed and the pressure resistance of the object to be cleaned, it is possible to perform appropriate cleaning processing while avoiding damage, and to improve the cleaning efficiency. Can be improved.

Further, dry ice snow is sprayed by adjusting the length of the distribution pipe so that dry ice snow is sprayed, and dry ice snow is selected and sprayed in an appropriate state according to the degree of contamination of the object to be cleaned. As a result, the cleaning efficiency can be improved. In particular, distribution pipes having different distribution pipe lengths are fixedly arranged on a cleaning line in accordance with a state to be cleaned in order to cope with a large amount of cleaning processing, and an object to be cleaned is automatically fed to the cleaning line. The washing position is set differently according to the flow pipes of different lengths, and the object to be washed is continuously passed through the fixed washing nozzle position, and the washing position is sequentially changed at each washing nozzle. , A large amount of objects to be cleaned can be efficiently cleaned in a short time.

In order to enhance the cleaning effect, it is effective to increase the flow rate of the continuously flowing jetting gas. By reducing the flow rate from 65 NL / min to 270 NL / min, the cleaning time can be reduced. It was confirmed that it was possible. However, it was confirmed that the burn-in board, the probe card, and the like consisted of a very thin needle-like stylus, and could be cleaned with a small nitrogen gas flow rate of 65 NL / min.

On the other hand, when there is a possibility that a defect may occur due to the electric charge of the object to be cleaned, an ionizing means may be provided in the injection gas supply system or the dry ice snow supply system to ionize the fluid. As a result, the electric charge of the dry ice snow mixed with the cleaning nozzle is almost 0V.
Was also confirmed.

As described above, by performing cleaning in accordance with the characteristics of the object to be cleaned, the object to be cleaned is not damaged,
The cleaning can be reliably performed, the inspection jig can be easily recycled and reused, and a polishing step for regeneration can be omitted in a probe card, for example.

[Brief description of the drawings]

FIG. 1 is a schematic system diagram showing an example of a dry ice snow cleaning device of the present invention.

FIG. 2 is a schematic system diagram showing an example of a flow pipe length adjusting mechanism used in the dry ice snow device of the present invention.

FIG. 3 is a partial sectional view of a triple tube structure nozzle.

[Explanation of symbols]

10: Dry ice snow cleaning device of the present invention, 1: Liquefied carbon dioxide gas container, 3: Opening / closing means, 5: Restriction mechanism, 7
... circulation pipe, 7a ... center pipe, 7b ... outer pipe, 7c ... flow path, 8 ... washing nozzle, 8a ... center ejection pipe, 8b ... outer pipe, 8d ... dry ice snow ejection port, 8g ... injection gas injection Mouth, 9 ... Dry ice snow supply system, 1
DESCRIPTION OF SYMBOLS 1 ... Injection gas source container, 14 ... Pressure regulator, 16 ... Ionization means, 18 ... Injection gas supply system, 19 ... Heating control means, 20 ... Control box, 21 ... Connection tool, 22 ...
Distribution pipe, 25: distribution pipe length adjusting mechanism, 27: distribution pipe of triple pipe structure, 28: washing nozzle of triple pipe structure, 29 ...
Dust collection hood, V1, V2, V3 ... Valve, 2, 4, 6, 1
2,15,17 ... conduit, G ... injection gas, T _L ... liquefied carbon dioxide, T _S ... dry ice snow

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 21/304 643 H01L 21/304 643Z 648 648L F-term (Reference) 3B116 AA46 BB21 BB71 BB82 BB88 BB89 4F033 AA04 BA02 BA03 BA05 BA06 GA01 QB02Y QB03X QB05 QB09X QB13Y QD02 QD21

Claims (2)

[Claims] 1. A method of washing dry ice snow by blowing dry ice snow formed by expanding pressurized liquefied carbon dioxide gas by a throttle mechanism toward an object to be cleaned from an outlet. Injection gas is injected into the peripheral portion in parallel with this, and the length of the flow path from the throttle mechanism to the injection port is adjusted to inject dry ice snow to wash the object to be washed. Ice snow cleaning method. 2. A liquefied carbon dioxide gas container for storing liquefied carbon dioxide gas and a flow reaching a cleaning nozzle for spraying dry ice snow through a throttle mechanism which is connected to the liquefied carbon dioxide gas container and expands adiabatically. A dry ice snow supply system consisting of a pipe and a gas supply vessel for injection consisting of a flow pipe connected to a gas supply container for injection and reaching an injection port of the gas for injection provided on the outer peripheral portion of the washing nozzle. A dry ice snow cleaning device, wherein the dry ice snow supply system is provided with a pipe length adjusting mechanism for adjusting a flow pipe length from the throttle mechanism to the washing nozzle, and the gas for injection is provided. A dry ice snow cleaning apparatus characterized in that an injection port provided on an outer peripheral portion of a cleaning nozzle of a supply system is an injection port for jetting in parallel with a jet direction of dry ice snow.