JP2003517917A - Improved object drying and cleaning process using controlled spray and gas quality - Google Patents

Abstract

(57) SUMMARY A method and apparatus for cleaning and / or drying objects that may be wet or contaminated during a manufacturing process are disclosed. The object is submerged in the cleaning liquid (27) in the closed chamber (11), and the spray particles (39) from the selected liquid (37) are introduced into the chamber above the cleaning liquid level (29) and this surface Then, a thin film (30) is formed. As the cleaning liquid is slowly drained (41), some spray particles settle on the exposed surfaces (14A, 14B, 14C) of the object, driving out and removing the cleaning liquid residues from the exposed surfaces by a "chemical squeezing" effect. I do. Surface contaminants are also removed by this processing step. When the cleaning liquid is discharged from the chamber, the chamber pressure is maintained at or near the external environment pressure. Inert gas flows are employed to provide smaller sized spray particles and / or to more fully diffuse within the chamber to provide the spray particles. In order to remove most of the contaminants from the selection liquid, intermittent filtration and split-flow filtration (159, 161, 175) are employed. A flow deflecting device redirects the initial flow of the selected liquid toward the supplementary filter, removing most of the "spikes" of contaminant particles that appear when the system is first started (when restarted). . An improved surface for spray particle generation is provided.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD OF THE INVENTION

The present invention relates to an improvement in performing a drying process and a cleaning process on a manufactured object such as an electronic device component by using a spray quality generated by a sonic means or an ultrasonic means.

[0002]

[Prior art]

Objects being manufactured utilizing processes associated with the application of liquids, fluids, etc., require that each part be thoroughly dried before continuing the manufacturing process. For example, in manufacturing integrated circuits, doping processing, photomask processing, etching,
The passivation process often requires the removal of liquid residues from the application of a particular liquid in one stage before proceeding to the next stage. Although these liquid residues must be completely dried and removed, the drying process is performed in a relatively short time with minimal energy and chemical consumption to achieve the drying process. Is ideal. Worksite sources have previously disclosed various methods of drying components such as integrated circuits using heated or superheated gases. Such approaches utilize heated gas, superheated gas, or direct beam irradiation to dry the object surface, or
It utilizes the synergistic action of an ultrasonic beam and an activated chemical bath to remove impurities from the surface of the object and to deliver the desired material to the surface of the object. These approaches are complex, typically require working at high temperatures, often require a few minutes of processing time, and require the use of particularly durable chamber walls for the processing chamber. Often there is.

[0003]

[Problems to be Solved by the Invention]

A chamber made of almost any material that works well at room temperature, is simple at the same time, is clearly complete without leaving significant residues and can be achieved in as little as a minute. It can also be done in a chamber with walls,
Only a very small amount of desiccant needs to be used, and a method for drying and cleaning an object in a manufacturing process in which thermal energy consumption is minimized among the energy consumption and a device related to this method are required. Becomes This treatment process should be able to be carried out over a wide temperature range and should preferably be easily scaleable to surfaces of any size.

[0004]

[Means for Solving the Problems]

The present invention uses such a small amount of low surface tension liquid suitable for such needs, and (optionally) a short time application of a reusable cleaning agent to dry and / or clean the object. An improvement in a method and apparatus associated with the method is provided. In one embodiment, the object to be dried is submerged in a cleaning liquid such as water in the chamber. The cleaning surface is coated with a very thin film of a selected liquid with low surface tension, such as isopropyl alcohol (IPA), which can be sonicated or ultrasonically vibrated by a thin stream of the selected liquid. Formed from a spray quality made. Other suitable liquids include ethyl alcohol, methyl alcohol, tetrahydrofuran, acetone, perfluorohexane, hexane and ether. The membrane is continuously replenished as needed, and the wash liquor coating the object to be dried is slowly dried. Once the cleaning liquid and the thin film have dried up, the "chemical squeegeeing" process step, discussed below, causes the selective liquid to briefly contact the surface of the object to remove residual moisture. Optionally dry N ₂ gas, CO after the chamber is drained
A heated cleaning solution such as gas or CO ₂ gas or an ambient temperature cleaning solution can be utilized for another chamber cleaning (purging) or drying process. Optionally, when the wash liquid is drained from the chamber, the chamber pressure is maintained at or near external environmental pressure.

[0005]

[Constitution of the invention]

In a first refinement, a fast flow of replenishment gas results in a controllable spread of the selective liquid, creating a “fog” with reduced spray drop size and improved drying and / or cleaning action. In a second refinement, a controlled flow of make-up gas is combined with a mask that captures heavier selective liquid particles (eg, those with a spray droplet size> 10 μm) to reduce spray droplet size, dryness and / Generates fog with improved cleaning action. In a third refinement, the selective liquid is continuously circulated and filtered to continuously remove substantially all contaminants having a diameter greater than the selected value, such as 0.05 μm. In a fourth refinement, an opening and closing adjuster (shutter) is used in the transfer system to suppress or substantially eliminate contaminant particle "spikes" that occur during the start-up phase of the transfer device. There is. A fifth refinement provides an improved atomizing particle generation system that utilizes an inert particle forming surface, which provides improved control of atomized droplet size while allowing the production of much smaller droplets. I have to.

The process parameters that can be changed to control this process are:
Oscillation frequency to generate spray particles from the selective liquid, typical spray particle diameter, transport speed of the selective liquid, pressure and temperature at which the selective liquid is transported to generate spray particles, used There is a temperature of the drying fluid (if used) and a choice of selection fluid and a drying fluid (if used) used. The present invention provides a small volume, on the order of 1 milliliter (ml) to 2 milliliters, for drying objects in chambers of 10 liters to 20 liters, or in smaller or larger volumes, as desired. Requires selection liquid. This approach offers several advantages. First, this process is at room temperature, or
It is carried out near room temperature, consumes little energy, and does not require the use of heated liquid or gas or superheated liquid or gas for the drying process. Second, this process uses a very small amount of selective liquid in a large volume of cleaning liquid (10 liters to 20 liters), and the mixture of cleaning liquid and selective liquid usually requires special handling for hazardous materials. It can be deposited without a procedure. Third, a wide range of inexpensive selection liquids can be used. Fourth, the selective liquid coating thin film minimizes the evaporation from the cleaning liquid remaining in the chamber after draining. Fifth, this process can be easily scaled up or down without making substantial changes to the equipment. Sixth, this treatment process removes large diameter contaminants that are not chemically bound to the object surface.

[0007]

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 illustrates one embodiment of an apparatus 10 useful in practicing the present invention. The enclosure chamber 11 is bounded by a housing 12 and is provided with a rack for holding objects 13A, 13B, 13C, etc. to be dried. Object 13
A, 13B, 13C are installed in or removed from the chamber 11 through a slidable hinged inlet passageway that is part of the housing 12 or an openable inlet passageway 15 that can operate otherwise. Will be When the inlet passage 15 is closed or mated, the chamber is sealed, preferably in a gastight manner, and residual gas in the chamber can be optionally removed. First
A port 21 and a first valve 23 associated therewith are mounted on the housing 12 and connected to a source 25 of water or other suitable cleaning liquid 27, in which the objects 13A, 13B, 13C is sunk. A second port 31 and a second valve 33 associated therewith are mounted on the housing 12 to provide the objects 13A, 13B,
Connected to a selective liquid source 35, such as a tank under pressure of a selected drying liquid or fluid 37 (referred to as "selective liquid") which primarily dries 13C, the pressure being maintained from 5 psi to 50 psi. There is. The third port 41 and the third valve 43 related thereto are provided in the first port 21 and the first port 21.
It may be the same as the valve 23, but is attached to the housing 12 to receive and drain the cleaning liquid 27 and the absorption selective liquid 37 from the chamber 11 or a first liquid tank or other suitable first tank. It is connected to the drainage receiver 45. The fourth port 51 and the fourth valve 53 related thereto are the second port 31 and the second valve 3.
A second liquid tank or fluid tank, which may be identical to 3, but which is mounted on the housing 12 and receives the selection liquid 37 and the spray drops 39 from the selection liquid from the chamber 11 and drains therefrom. It is connected to a suitable second drainage means 55 other than this.

Initially, the objects 13A, 13B, 13C are installed in a rack or cassette (not shown) in the chamber 11, the inlet passage 15 is closed or mated, and the chamber bar is at or near atmospheric pressure. And the cleaning liquid 27 has the first pressure.
It is put into the chamber through the port 21 and the first valve 23 so that the object is sufficiently submerged in the cleaning liquid. Next, the first valve 23 is closed. Alternatively, the objects 13A, 13B, 13C are partially submerged in the cleaning liquid 27 such that some of their surfaces are exposed above the exposed surface of the cleaning liquid. Then, a thin flow of the selective liquid 37 passes through the second port 31 and the second valve 33,
It is received by a piezoelectrically driven head 61 and an oscillating sonic nozzle or an oscillating ultrasonic nozzle 63, which oscillates in the range of 10 kHz ≤ f ≤ 10,000 kHz, or more preferably in the narrower range of 20 kHz ≤ f ≤ 100 kHz. It vibrates at the selected frequency. The drive head 61 is connected to and driven by the frequency generator 64, which is preferably located outside the chamber 11 and the vibration frequency f can be selected within the indicated range. It can be so. When the selection liquid 37 is present in the vibrating nozzle 63, and the nozzle is vibrating, the selection liquid 37 becomes a plurality of spray droplets 39.
To the upper portion 11U of the chamber which has not yet been filled with the cleaning liquid 27 and the settled objects 13A, 13B, 13C.
Occupy most or all of the.

FIG. 2A shows a preferred drive head 61 that can be used with the apparatus shown in FIG.
A and the vibrating nozzle 63A are illustrated. The vibrating nozzle 63A preferably has a hollow column 65A formed therein with a diameter d (col) ≉200 μm, through which the selective liquid 37 (shown by diagonal lines) flows. Then, the vibrating nozzle 3 drops the selection liquid 37
9 is “shaken off”, which forms spray droplets in a substantially cylindrical pattern and moves to the upper part of the cleaning liquid in the chamber 11. FIG. 2B illustrates another suitable drive head 61B and a vibrating nozzle 63B having a thin hollow column 65B inside through which the selective liquid 37 flows.
The housing 67B surrounds the nozzle 63B and directs an annular hot or cold inert gas 69B towards the spray droplet 39, which travels into the chamber in a conical or otherwise desired pattern, The spray droplets are arranged in a more improved distribution state throughout the chamber. Many other head / vibration nozzle combinations can be used here. It has been found that the adoption of higher frequencies f tends to produce spray drops 39 with a smaller average diameter d (mean). For the vibration frequency f in the range of 20 kHz ≦ f ≦ 100 kHz, the average spray droplet diameter is estimated to be in the range of 10 μm ≦ d (mean) ≦ 50 μm.
By varying the diameter d (mean) of the thin film opening 66 and varying the vibration frequency f of the vibrating nozzle 63A or 63B, the average spray droplet diameter can be varied.

The selection liquid 37 should be non-reactive with the objects 13A, 13B, 13C and also with the wall of the chamber 11 and has a surface tension substantially lower than that of the cleaning liquid. Should be Suitable selection liquids include isopropyl alcohol, ethyl alcohol, methyl alcohol, tetrahydrofuran, acetone, perfluorohexane, hexane, ether, as well as many other low surface tension liquids and fluids. If any of these substances are used as the selection liquid, it is not necessary to provide a chamber wall made of a particularly resistant material. The selective liquid 37 is held in the selective liquid source 35 at a pressure of 5 psi to 50 psi, which exceeds the atmospheric pressure, to facilitate the transportation and to suppress a slight volatilization of the selective liquid. Occurs naturally. Deionized water, which is a preferred washing solution, has a surface tension σ = 73 dynes / cm at a temperature T≈20 ° C., and organic molecules such as methyl alcohol, ethyl alcohol, isopropyl alcohol, n-hexane and ether have a temperature T = 20 ° C. Since the surface tension σ is in the range of 17 dyne / cm ≦ σ ≦ 23 dyne / cm,
(Selection liquid) << becomes σ (selection liquid) at room temperature. It is preferred here to use the selection liquid 37 at or near room temperature. When the selective liquid 37 is used at a temperature substantially higher than room temperature, the surface tension of the selective liquid 37 and the surface tension of the cleaning liquid 27 can be lowered relatively, and therefore, the chemicals which have been the reliance on this processing process. Can interfere with the squeezing effect.

The atomized particles are groups or aggregates of molecules of the selective liquid 37 that have not yet undergone phase modification and have not reached the vapor form. Therefore, the energy E (spray quality) required to convert 1 gram of selective liquid 37 into spray droplets 39 using a vibrating nozzle (1.6 watts for a typical sonic head, or 100 joules / minute for a flow rate of 2 ml / min). (below gm) is much lower than the energy of vaporization E (steam) required to heat convert one gram of the selective liquid 37 into the form of steam. The ratio E (spray quality) / E (steam) is estimated to be less than 2 percent. The formation of atomized particles can be carried out at or near room temperature, but it is not necessary to employ very high temperatures such as T = 60 ° C. to 200 ° C. and this process is not recommended. Further, only a small amount of the selective liquid 37, for example, about 1 ml to 5 ml is required to dry the plurality of objects 13A, 13B, 13C in the chamber 11. The spray drops 39 move into the chamber 11 and most of these drops are on the exposed surface 29 (preferably in a quiet state) of the cleaning liquid 27 and a thin film 30 of variable thickness h (spray quality).
Deposit as. The estimated time required to form this thin film 30 is 40 to 60 seconds. Some of the spray droplets 39 that join the membrane 30 diffuse into the cleaning liquid 27, and therefore
If the membrane is not replenished with another spray drop, the membrane 30 will dissipate quickly and substantially.
The volumetric flow rate r (sel) of the selective liquid 37 toward the vibrating nozzle 63 is such that
The rate of bonding to is adjusted to be sufficient to maintain or increase the selected thickness h (spray quality) for this film. The preferable range for this film thickness h (spray quality) is 0.5 mm ≤ h (spray quality) ≤ 5 mm, but this thickness is the volume flow rate r (se
It can be increased by increasing l). For the chamber 11 where the exposed surface (upper surface) of the cleaning liquid 27 has an area of about 900 cm ² , the selection liquid 3
A volume flow rate of 7 is r (sel) = r2 = 1 ml / min to 5 ml / min. Normally,
The volume flow rate r2 = 1 ml / min to 2 ml / min is a sufficient height. The time required to remove the liquid in the chamber at a drainage rate of 5 mm / sec is about 20 to 40 seconds for a semiconductor wafer having a diameter of 10 to 20 cm. Therefore, the amount of the selective liquid 37 which is absorbed by the cleaning liquid 27 or diffuses into the cleaning liquid in the middle of the time (60 seconds to 100 seconds) required to establish the membrane and drain the liquid from the chamber is extremely small. Since only a very small amount of selective liquid 37 is used in this process, the selective liquid source 3
5 may have a relatively small volume of 20 to 25 ml, and the selective liquid source 35 may be installed at a considerable distance from the chamber 11 such as 1 to 4 meters. As a result, the safety of the treatment process using a selective liquid having a low flash point or a selective liquid that may cause an explosion is improved.

Although a very small amount of the selective liquid 37 spontaneously evaporates at the processing temperature, preferably at room temperature,
It is based on the equilibrium vapor pressure coefficient of the selective liquid at that temperature. Naturally, the vaporized portion is relatively small at room temperature in the closed chamber 11, and the vapor portion of the selective liquid 37 rapidly equilibrates with the liquid film and the atomized portion of the selective liquid 37. . When a treatment temperature much higher than room temperature is adopted, the equilibrium vapor pressure coefficient of the height is relatively high, and with the concomitant increase in the vapor of the selective liquid, the selective liquid 3
7 will be generated. There is no recognition that such spontaneous evaporation of a small portion of the selective liquid 37 is a useful part of the drying process. After the spray drop film 30 has been established on the surface 29 of the cleaning liquid 27, ie after 40 to 60 seconds, the cleaning liquid 27 is slowly discharged from the chamber 11 and the third
It enters the drainage tank 45 through the port 41 and the third valve 43. It takes an estimated 20 to 40 seconds to discharge the cleaning liquid 27 in the chamber containing 10 to 20 liters of the cleaning liquid 27. A preferable range of the discharge speed r (drainage) is a range in which the height of the cleaning liquid 27 in the chamber 11 is reduced from 3 mm / sec to 10 mm / sec, and r (drainage) = 5 mm / sec. This is the preferred discharge rate for this process. The drainage occurs slowly in order to store the thin film 30 of the selective liquid 37 at the position of the separately exposed surface 29 of the cleaning liquid. As the cleaning liquid 27 is discharged, the vibration nozzle 63
The thin streak-like flow of the selective liquid 37 through the nozzle continuously produces the spray droplet 39.
The volumetric flow rate r (sel) of the selection liquid 37 can be adjusted to reach a higher value or a lower value as the cleaning liquid 27 (including the absorbing spray particles 39) progresses.

FIG. 2C illustrates cleaning the object and / or drying the object.
It illustrates an improved ultrasonic drive that delivers selection liquid 117 and selection liquid 119 (eg, room temperature isopropyl alcohol (IPA), etc.) in the form of a spray.
The first fluid transport line 101 conveys the selective liquid from the selective liquid source 103 to the first end of the axial chamber 105, which axial chamber has a frequency of 10 kHz ≦ f ≦ 10,000k.
Substantially cylindrical ultrasonic nozzle 10 vibrating at a frequency f within a selected frequency range such as Hz
The boundary is defined by 7. The nozzle 107 is driven by the ultrasonic drive head 109, but the head may include a plurality of current carrying coils. When the direction of the coil current is iteratively reversed, the nozzle 107, which is provided with the piezoelectric material, is set into an oscillating state by the reverse flow of the coil current, "shaking off" the atomized droplets of the selective liquid. The apparatus of FIG. 2C has a second fluid transport line 1 supplied by an inert gas source 113.
11, which carries the gas to an inert gas plenum 114, in which case the plenum wall 115 has a small opening 1 near the second end of the axial chamber 105.
It has 16. The fluid transfer line 111 preferably conveys an inert gas such as N ₂ or CO to the plenum 114 at a flow rate of 2 to 10 liters per minute (LPM) at about room temperature. Some or all of the inert gas is plenum 114
From the plenum at the location of the plenum opening 116 in a selected (outward) direction, resulting in a locally reduced total gas pressure, which results in a divergent stream 11 of selective liquid spray particles.
Will result in 7. If there is no inert gas flow through the plenum opening 116,
Only the selective liquid spray particles 119 are developed and appear only in the central region surrounding the nozzle axis AA below the second end of the nozzle 107. Incorporation of an inert gas flow through the plenum opening 116 causes the atomized particles to flow over a larger “cone angle” θ _{c, C} than would occur if no inert gas were present.

FIG. 2D also illustrates an improved ultrasonic drive that delivers selective liquids 137, 139 in the form of a spray to clean the object and / or dry the object. The first fluid transport line 121, the selective liquid source 123, the axial chamber 125 bounded by the substantially cylindrical ultrasonic nozzle 127, and the ultrasonic drive head 1.
29, the second fluid transport line 131, the inert gas source 133, the inert gas plenum 134, the plenum wall 135, the plenum opening 136, each of the components 101, 103, 105, 107, 109, 111 in the apparatus of FIG. 2C. , 113, 1
It serves the same purpose as 14, 115, 116. The embodiment shown in FIG. 2D is
Larger attendant cone angle θ _{c, D} generated in the absence of inert gas
To generate the spray particles 137. In FIG. 2D, the inert gas is at a substantially constant plenum pressure, or, as shown in FIG. 2E, a plenum pressure p that varies substantially periodically with respect to time t between a minimum pressure value and a maximum pressure value. (Plenum) anyway, it is continuously driven out of the plenum opening 136. This pressure fluctuation produces an inert gas pressure wave 141, but the associated pressure gradient exists near the plenum opening 136. The pressure wave 141 is generated by the nozzle 12
Separation of atomized particles 117 away from the central region of 7 into smaller particle groups produces smaller atomized particles and also causes the particles to be outwardly oriented within a wider associated cone angle θ _{c, D.} Spread. The atomized particles 139 generated in a state where the central region is located near the axis of the nozzle 127 maintain a larger particle size, and one or more particle masks or particle absorbers 141 located in the central region below the nozzle 127, 1
Captured by 43. The selective liquid spray particles 139 captured by the particle masks 141 and 143 are discharged into the reservoir 144 and can be reused if desired. The embodiment shown in FIG. 2D produces spray particles 137 with a larger associated cone angle θ _{c, D} and a smaller average spray quality diameter, which is larger than the spray particles of larger diameter. Has a tendency to move parallel to the nozzle axis A-A,
This is because there is a strong tendency to be captured by the one or more particle masks 141 and 143 arranged in the center.

As the cleaning liquid 27 drains from the chamber 11 of FIG. 3, the objects 13A, 13B
, 13C, 14A, 14B, 14C respectively, are exposed more and more above the exposed cleaning liquid surface 29 and the membrane 30 located thereabove, and the spray drops 39 in the upper part of the chamber 11U are shown in FIG. As shown, exposed surfaces 14A, 14B, 1
Deposit on top of 4C. Further, a part of the membrane 30 of the selective liquid 37 moves toward the third port 41 together with the cleaning liquid 27, rather than moving toward the object surfaces 14A, 14B, 14C.
May be deposited on exposed parts of. The selection liquid 37 is selected so as to have a surface tension σ (sel) much smaller than the surface tension σ (cleaning liquid) of the cleaning liquid 27. When the cleaning liquid 27 is water, the accompanying surface tension is σ (cleaning liquid) = 7 at room temperature.
It is 3 dynes / cm. In this case, the selection liquid 37 may be isopropyl alcohol (IPA), ethyl alcohol, or methyl alcohol, and the surface tension at this time is room temperature, and σ = 21.7 dyne / cm and σ = 22.6. Dyne / cm, σ =
It is 22.8 dynes / cm. The selection solution 37 is chosen for its ability to displace or solubilize the wash solution regardless of the processing temperature employed. Room temperature (T = 20 ° C.) or lower temperatures are also adopted here. At somewhat higher temperatures, this process works satisfactorily. When the exposed portions of the object surfaces 14A, 14B, 14C receive the spray droplet 39 of the selective liquid 37, a new droplet 16A, 16B, 16C of the spray droplet 39 or selective liquid 37 is formed on each exposed portion. As the cleaning liquid 27 is discharged from the chamber 11 and after the drainage is completed, the selective liquid 37 of the films 16A, 16B, 16C remains on the exposed portions of the object surfaces 14A, 14B, 14C. Cleaning liquid 2
Most or all of 7 are driven off, but this is mainly due to the surface tension σ (s
el) is much smaller than the surface tension σ of the cleaning liquid 27 (cleaning liquid). The cleaning liquid 27 driven off by the selective liquid is the exposed surface 14A of the objects 13A, 13B, 13C.
, 14B, 14C, and is discharged together with the amount of cleaning liquid existing in the chamber. The selective liquid 37, which forms a film on the surfaces 14A, 14B, 14C of the objects 13A, 13B, 13C, also flows down on these surfaces and is discharged together with the corresponding amount of the cleaning liquid 27. Therefore, the membranes 16A, 16B and 16C of the selective liquid 37 are the cleaning liquid 2
7 and the selection liquid 37 on the exposed surfaces 14A, 14B, 1 of the objects 13A, 13B, 13C.
It acts as a "chemically squeezed substance" when removed from 4C.

The chemical squeezing action of the exposed surfaces 14A, 14B, 14C of the object has another advantage. Not only does this treatment process dry the surface of the object, but it also removes most of the contaminant particles from the object surface if the large contaminant particles are not chemically bound to the host surface. When the test was performed by applying the exposed silicon surface before the chemical pressing treatment, as shown in the second row of Table 1, the diameter of the silicon surface was at least 0.3 μm.
A large number of contaminant particles were identified. Then, a chemical squeeze treatment was performed and the silicon surface was tested again after the chemical squeeze treatment was completed. As shown in column 3 of Table 1, the number of contaminant particles decreased after the chemical squeeze treatment was completed. It was confirmed that it was doing. These results indicate that chemical squeezing alone removes 12 to 100 percent of contaminant particles larger than 0.3 μm in size, depending on size.

[Table 1] Size of large contaminant particles removed by chemical compression Number of particles before chemical compression 0.329-0.517 μm 8 7 0.518-0.810 7 2 0.811-1.270 7 2 1.271-1.990 3 1 1.991-3.130 6 1 3.131-4.910 6 0

The cleaning liquid 27 is sufficiently spilled from the chamber 11, and the objects 13 A, 1
By the time the surfaces 14A, 14B, 14C of 3B, 13C are fully exposed, the second port 31 and the second valve 33 are closed, the vibration nozzle 63 is shut off, and the fourth port 5 is closed.
The first and fourth valves 53 are opened. Then, the remaining selective liquid 37 and spray droplet 3
9, the cleaning liquid 27, the vapor from the cleaning liquid and the vapor from the selective liquid are removed from the chamber 11 through the fourth port 51. This portion of the process may take an additional 10 to 20 seconds, but if desired, may be continued for a longer period of time to remove residual selection liquid 37
The residual cleaning liquid 27 can be completely removed from the membranes 16A, 16B and 16C and further from the chamber 11. At this point, the drying process of the objects 13A, 13B, and 13C is substantially completed. Optionally hot or room temperature dry nitrogen N ₂ , carbon monoxide CO, carbon dioxide CO ₂ ,
Alternatively, another inert gas may be introduced into the chamber 11 through the fifth port 71 and the associated fifth valve 73 to clean the chamber 11 and / or the object 1
Residual material can be cleaned from the exposed surfaces 14A, 14B, 14C of 3A, 13B, 13C. The hot purge gas is received from the purge gas tank 75 into the chamber 11 and removed through the sixth port 81 and the sixth valve 83, even though this port and valve are the same as the fifth port 71 and the fifth valve 73, respectively. Good. The hot purge gas is received from the chamber 11 into a used purge gas tank 85 for recycling, treatment, or disposal. If this part of the process is included, it may take an additional 30 to 60 seconds.

FIG. 4 is a flow chart showing the process steps performed in one embodiment of the present invention. In step 91, the object 13A to be dried and / or washed
, 13B, 13C (FIGS. 1 and 3) are placed in the chamber and the chamber is closed. In step 93, the wash liquid 27 is placed in the chamber to partially or (preferably) fully settle the object. In step 95, a spray drop of selection liquid 37 is formed in the chamber and a film of selection liquid is formed and maintained on the exposed surface of the cleaning liquid. In step 97, the cleaning liquid 27 and the absorption selective liquid 37 are slowly ejected from the chamber, eventually exposing the surface of the object to the spray droplets, so that a film of selective liquid is formed on the object surface, but optionally. The chamber pressure is maintained near or above the external environmental pressure. In step 99, the selective liquid film on the surface of the object is subjected to a chemical squeezing action to remove residual cleaning liquid 27 and residual selective liquid 37 and contaminants from the surface of the object. In step 101 (optional), the remaining selection liquid 37 and cleaning liquid 27
Are removed from the chamber. In step 103 (optional), a purge gas is passed through the chamber to remove residual gas and / or liquid particles from the chamber. Objects already dried and / or washed at this point can be removed from the chamber or may be further processed in the chamber. No matter what discharge amount r1 is selected, the cleaning liquid 27 from the chamber 11
The partial vacuum is generated in the chamber by the removal of the above. However, this partial vacuum cannot be relaxed sufficiently by only receiving a small amount of the selective liquid from the drive head 61 and the vibrating nozzle 63 into the chamber. If the chamber 11 is sufficiently airtight, little or no external gas will enter the chamber in response to the creation of this vacuum. However, many chambers are not sufficiently airtight and in such cases there is a significant influx of gas from the external environment, possibly with one or more pollutant particles being carried along with this gas. Selected objects 13A, 13B, 1
It may deposit on the exposed surfaces 14A, 14B, 14C of 3C. This has been observed in some, but not all, of the procedure procedures and device tests disclosed herein.

Referring to FIG. 3, a substantially inert substitution gas 122, such as N ₂ , CO, or CO ₂ , is optionally provided and is in fluid communication with the chamber 11. Storage 1
Inert gas 122 in 21 passes through port 123 and its associated valve and pressure controller 125 and enters chamber 11. The valve and pressure control device 125 uses the port 41 and the valve 43 to detect the changing pressure generated in the chamber when the cleaning liquid 27 is discharged from the chamber. In response to this varying pressure, the valve and pressure control device 125 allows sufficient inert gas 122 to enter the chamber from the inert gas reservoir 121, so that the chamber pressure is pressure p≈p (external). Where p (external) is approximately equal to or higher than the local pressure outside the chamber. A chamber pressure p somewhat higher than the local external pressure p (external) is preferred here, so that if the chamber is not tight enough, the inert gas 122 will leave the chamber 11 and migrate to the external environment. And slows the inflow of gas from the external environment. Optionally chamber 11
The pressure p maintained inside may be somewhat lower than p (external), perhaps 0.8
p (external), which also slows the flow of gas from the external environment into the chamber. The cleaning liquid 27 is sufficiently discharged from the chamber 11 and the selected object 13
After the surfaces 14A, 14B, 14C of A, 13B, 13C have been thoroughly dried and / or cleaned, the inert gas 122 is removed from the chamber before performing the next step to treat the selected object. It is removed to the inert gas reservoir 127. Alternatively, the valve and pressure controller 125 need not detect the internal pressure of the chamber 11 if the discharge amount r1 of the cleaning liquid 27 from the chamber 11 is controlled sufficiently well. In this approach, the valve and pressure controller 125 admits the inert gas 122 from the inert gas reservoir 121 at a programmed volumetric flow rate r3, where the flow rate r3 is when the cleaning liquid 27 is exhausted from the chamber. , Sufficient to maintain an internal pressure p≈p (external) inside the chamber 11 or higher than this. The temperature T of the inert gas 122 is preferably at or near the temperature of the cleaning liquid, which temperature is usually room temperature, or somewhat lower or somewhat higher than room temperature. The purge gas reservoir 75 may function as the inert gas reservoir 121, in which case
A valve and pressure control device 125 is provided.

FIG. 5 illustrates an improved flow filtration device that seeks to maintain a selective liquid (such as IPA) in the relative absence of contaminants with dimensions exceeding a relatively small diameter. There is. The selective liquid (for example, IPA) is stored in the selective liquid reservoir 151 and stored at room temperature at 1
Pumped through a first check valve 155 along a first fluid transfer line 153 by a positive displacement pump 157 having a volumetric flow rate preferably in the range of 1 liter to 10 liters per minute (LPM). . The selective liquid in the first line 153 preferably has a plurality of openings having a diameter in the range of 0.1 μm to 0.2 μm, and then passes through the first filter 159, and then has a diameter in the range of 0.02 μm to 0.1 μm. Of (approximately 0.0
It further passes through a second filter 161 which preferably has a plurality of openings (preferably equal to 5 μm). The first filter 159 removes most or all of the contaminant particles in the selective liquid having a diameter larger than the diameter of the first filter opening.
The second filter 161 removes most or all of the contaminant particles in the selection liquid having a diameter larger than the diameter of the second filter opening, and in particular, it has a diameter larger than that of the first filter opening. Such residual contaminant particles are also removed. Optionally, the first filter 159 and the second filter 161 may be deleted. Next, the selective liquid passes along the first line 153, and reaches the joint 163 where the first line intersects the second fluid transport line 165 and the third fluid transport line 167. The selective liquid in the second line 165 passes through the second check valve 169 and then returns to the selective liquid reservoir 151. After the selective liquid in the third line 167 has passed through the third check valve 171 (preferably a needle valve), the selective liquid in the range of 0.02 μm to 0.1 μm (
(More preferably equal to about 0.05 μm) through a large three filter 175 having a plurality of openings of diameter. The selective liquid in the third line 167 is then received in the filtered selective liquid reservoir 179, which may contain N ₂ , CO, or other suitable inert gas. It is pressurized by the inert gas from the inert gas line 181 fed by the active gas source 183. The triply filtered selective liquid then passes through the vibrating head and nozzle 185 to wash the object and / or
Alternatively, the object is dried. Optionally, the selective liquid reservoir 151 has a pressure sensor and a regulator 187 that utilizes pressure feedback to maintain a generally constant pressure within the reservoir.

Each of the three filters 159, 161, 175 is preferably a track-etched polycarbonate filter. First fluid transportation line 1
53 and the second fluid transfer line 165 are preferably Teflon tubing having an inner diameter in the range of 0.125 mm to 0.25 mm. The third fluid transfer line 167 is preferably a Teflon tube having an inner diameter in the range of 0.1 mm to 0.2 mm. When the second check valve 169 is in the open position and the third check valve 171 is in the closed position, the selected liquid passes through the first filter 159 and the second filter 161, and the first fluid transport line 153 and the second fluid transfer line 153. It flows in the fluid transportation line 165 and returns to the selective liquid storage device 151. When the second check valve 169 is in the closed position and the third check valve 171 is in the open position, the selected liquid passes through the first filter 159, the second filter 161, and the third filter 175, and the first fluid It flows in the transportation line 153 and the third fluid transportation line 167, and passes through the nozzle 185. Second check valve 1
Since at least one of 69 and the third check valve 171 is open at all times, the filtering action does not stop and the selection liquid continues substantially continuously across two or three of the filters. Circulate. Most of the contaminant particles in the selective liquid are removed in the fluid path from the first line to the second line. If contaminants other than these are present, they act as a flow divider to remove selected portions of the already filtered selective liquid to prepare for the next filtration process from the first line to the third line. Removed by fluid path.

FIG. 6 illustrates a device that suppresses or eliminates “spikes” of contaminant particles that develop when the selective liquid (SL) delivery device is started after a period of inactivity. The selective liquid reservoir 191 is supplied by a selective liquid fluid line 193 from a selective liquid source 195. The selective liquid reservoir 191 is received in the inert gas line 197,
It is pressurized by the inert gas from the inert gas source 199. The selective liquid reservoir has a nozzle or other liquid outlet terminal 201 to allow the selective liquid to be delivered at a controllable rate, to wash the object and / or to dry the object. There is. Liquid flow mask 203 having open portion 205 and opaque portion 207
Is located adjacent to the nozzle 201 and is movable by a motor or other manual or automatic mask moving mechanism 209 in a direction transverse to the normal direction of flow of the selective liquid. The redirected selective liquid is passed through one or more selective liquid filters 208 before returning to the selective liquid source 195. The mask 203 acts in a manner similar to the operation of the focal plane shutter of the camera and is preferably made of a relatively inert material such as GORE-TEX. Other liquid redirection (re
direction) means to direct an initial amount of selective liquid through a (special) selective liquid filter to "spike" contaminant particles that develop when the system is first started.
Most or all of the can be removed. When the selective liquid transport device including the selective liquid reservoir 191 as one component is started after being unused for a considerable period of time, it interferes with the initial selective liquid flow and is redirected. For that purpose, the opaque portion of the mask 203 is positioned across the nozzle 201. The first flowing selection liquid (immediately after the system is started) may have more contaminant particles in it than it normally does, and the contaminant particles may be transferred during the preceding inactivity period. It may be accumulated in the device (selection liquid storage device, selection liquid transfer line, etc.). The selective liquid in this initial selective liquid stream is preferably redirected through a separate liquid filtration system (not shown in FIG. 6) to remove more contaminant particles from the liquid than normal. After a selected time period, the mask 203 may be moved in the transverse direction by the movement mechanism 209, which may be as short as 2 seconds to 3 seconds or as long as 60 seconds to 120 seconds. Is moved to position the opening 205 of the mask 203 in the normal path of the selective liquid flow from the nozzle 201. At this point, the selective liquid flows from the selective liquid reservoir 191 through the nozzle 201,
Furthermore, the object is washed and / or the object is dried through the usual channels for transporting the selective liquid.

FIG. 7 illustrates an improved spray generator. A relatively large drop 211 of selective liquid (SL) from selective liquid reservoir 213 is carried by one or more fluid transport lines 215 and deposited on the exposed surface of a suitable solid receptor 217. Fluid transportation line 215
Preferably allows a selection liquid flow rate of 0.1 ml / min to 10 ml / min. The size of the selective droplets may be as small as the surface tension of the selective liquid allows, or larger, if desired. The solid receptor 217 is made of silicon nitride (Si ₃ N ₄ ),
It is preferably a silicon nitride hydroxide (Si _x N _y H _z ) or a chemically inert material such as a suitable material other than these. The solid receptor 217 is continuous with the piezoelectric (PZT) crystal 219 on one surface or bottom surface. The piezoelectric crystal 219 is electrically driven by two or more electrodes 221A and 221B, which are driven by an AC voltage element 223. The AC voltage element 223 preferably provides an AC voltage of one or more frequencies in the range 20 kHz to 5,000 kHz, and more preferably in the range 20 kHz to 750 kHz. When the piezoelectric crystal 219 expands and contracts according to the applied AC voltage,
The solid receptor 217 vibrates, and the deposited droplets of the selective liquid 211 have a diameter of preferably 1 μm.
To a larger number of smaller (atomized) particles 225 ranging from 50 μm to 50 μm.
These small spray particles 225 escape from or separate from the solid receptor 217 and are used to substantially clean the object and / or dry the object. As the drive frequency f of the piezoelectric crystal 219 increases, the average diameter of the atomized particles produced by this device should decrease.

[Brief description of drawings]

FIG. 1 illustrates one embodiment of a preferred apparatus for practicing the present invention, showing an object submerged in a cleaning liquid in a chamber.

2A, 2B, 2C, 2D are schematic views of a spray producing vibrating nozzle suitable for use with the present invention, and FIG. 2E is suitable for use with the apparatus of FIG. 2D. 3 is a graph illustrating the change over time in the plenum pressure of the inert gas.

FIG. 3 is a diagram illustrating a state in which a part of the cleaning liquid is drained from the chamber, exemplifying the apparatus of FIG.

[Figure 4]   3 is a flow chart of one embodiment of the method of the present invention.

[Figure 5]   FIG. 3 is a schematic view of a selected liquid intermittent filtration device according to the present invention.

FIG. 6 is a schematic diagram of an opening and closing adjustment device that can be used with a spray generation and delivery system according to the present invention.

[Figure 7]   1 is a schematic view of a spray generation device according to the present invention.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B05C 15/00 B05C 15/00 4F040 B05D 1/18 B05D 1/18 4F042 3/10 3/10 F 3 / 12 3/12 F B08B 3/12 B08B 3/12 D F26B 21/14 F26B 21/14 H01L 21/304 643 H01L 21/304 643D 648 648J 651 651 651H (81) Designated country EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE), OA (BF, BJ, CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, KE, LS, MW, SD, SL, SZ, Z, UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, CA, CH, CN, CU, CZ, DE, DK, EE, ES, FI, GB, GE, GH, GM, HU, ID, IL, IS, JP, KE, KG, KP, KR, KZ, LC, LK , LR, LS, LT, L U, LV, MD, MG, MK, MN, MW, MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, UA, UG, UZ, VN, YU, ZW F terms (reference) 3B201 AA03 AB01 BB03 BB22 BB32 BB85 BB92 BB95 CC11 3L113 AA03 AC26 AC67 BA34 4D074 AA09 BB02 DD04 DD21 DD31 4D074 A76 AA01 AB03 AA01 BB12X BB13X BB24Z BB65Z DC21 EA05 4F033 PA01 PA08 4F040 AA12 AB13 AB16 BA42 DB10 4F042 AA06 CC 04 CC07 DA01 DA08 DE01 [Summary of Continuation] Eliminates most of the "spikes" of pollutant particles that appear when started (when restarted). An improved surface is provided for spray particle generation.

Claims (45)

[Claims] 1. A device for performing at least one of a process for drying an object and a process for cleaning an object, the device comprising a closed chamber for receiving and containing a selected object to be dried. , The closed chamber has a releasable inlet passage that allows a selected object to be placed in and removed from the closed chamber, the closed chamber having a selected surface tension. Having a first opening in fluid communication with a source of cleaning liquid for delivering the cleaning liquid into the closed chamber to cause the selected object to partially or fully submerge in the cleaning liquid, Has a second opening that allows the wash liquid to exit the closed chamber at a volumetric flow rate r1 existing in a selected volumetric flow range of And a vibrating head for receiving a selected liquid having a third opening in fluid communication with the closed chamber and having a surface tension substantially lower than that of the cleaning liquid. And the vibrating head receives the selected liquid at a volumetric flow rate r2 existing in a second selected volumetric flow range,
An apparatus, characterized in that a selected liquid is caused to form atomized particles in a closed chamber. 2. The apparatus further comprises an inert gas source positioned adjacent the vibrating head to introduce the inert gas in one or more selected directions, the inert gas source being present. An apparatus according to claim 1, wherein the spray particles are moved away from the vibrating head at an increased angle relative to the axis of the vibrating head relative to the movement of the spray particles when not in motion. 3. The method of claim 2, further comprising a mask positioned within the chamber to receive particles remaining in the vibrating head and moving substantially parallel to the axis of the vibrating head. The device according to. 4. The inert gas source further comprises a pressure adjusting device adjacent to the vibrating head that allows the inert gas to be introduced at a controllable time-varying gas pressure. The device of claim 2 characterized. 5. The apparatus of claim 4, further characterized in that the gas pressure changes over time, which is generally periodic over a period of time. 6. The apparatus according to claim 1, wherein the vibrating head vibrates at at least one frequency in the range of 10 kHz ≦ f ≦ 10,000 kHz. 7. The frequency f is selected such that the diameter d of at least one atomized particle lies in the range 10 μm ≦ d ≦ 50 μm.
The device according to. 8. The apparatus of claim 6, further characterized in that the vibrating head vibrates at at least one frequency in the range 20 kHz ≦ f ≦ 80 kHz. 9. The apparatus of claim 1, further characterized in that the selected liquid is substantially chemically unreactive with the selected body. 10. The selected liquid is selected from the category of substantially non-reactive liquids consisting of isopropyl alcohol, ethyl alcohol, methyl alcohol, tetrahydrofuran, perfluorohexane, hexane, ether. The device according to claim 9, wherein 11. The depth of the cleaning liquid in the closed chamber is 3 mm / sec and 1
Device according to claim 1, characterized in that the flow rate r1 in the first selected range is chosen to decrease at a rate between 0 mm / sec. 12. The flow rate r2 in the second selected range is 1 ml / min ≦ r.
Device according to claim 1, characterized in that it is in the range 2 ≦ 5 ml / min. 13. A device according to claim 1, characterized in that the selected liquid is received in the closed chamber at a pressure p in the range of 5 psi ≦ p ≦ 50 psi. 14. A source of the selected liquid is connected to the vibrating head,
The apparatus of claim 1, further characterized by being installed outside the closed chamber. 15. The method of claim 14, further characterized in that the source of the selected liquid is located at least 1 meter away from the closed chamber.
The device according to. 16. Apparatus according to claim 14, characterized in that the source of the selected liquid contains a volume V of the selected liquid of the order of only 25 ml. 17. The particle diffusing means is further disposed inside the closed chamber near the vibrating head to diffuse the atomized particles within the closed chamber as the atomized particles move away from the vibrating head. And claim 1
The device according to. 18. The particle diffusing means has a source of pressurized gas maintained at a temperature T in the range of 20 ° C. ≦ T ≦ 100 ° C., and the particle diffusing means is characterized in that the atomized particles are 18. The apparatus of claim 17, further comprising gas directing means for directing the pressurized gas to change direction as it moves away from the vibrating nozzle. 19. The method further characterized in that substantially all of the atomized particles are formed within the closed chamber without changing the phase of the selected liquid.
The device according to claim 1. 20. The apparatus of claim 1, further characterized in that the atomized particles are formed within the closed chamber with an energy consumption of less than 2 Joules per second. 21. A gas source of a substantially inert gas, which is provided in the closed chamber and is connected to a heated inert gas source,
A fourth opening for introducing an inert gas into the closed chamber from a heated inert gas source, the fourth opening provided in the closed chamber, which may be the same as the fourth opening; And a fifth opening adapted to allow the device to exit the closed chamber. 22. A second source of substantially inert gas, said second chamber being provided in said closed chamber and connected to a second source of inert gas,
A fourth opening for introducing a second inert gas from the inert gas source into the closed chamber; and a fourth opening provided in the closed chamber, which may be the same as the fourth opening. A fifth opening for allowing the inert gas of the chamber to exit the closed chamber, and a second inert gas source connected to permit and control the second inert gas into the closed chamber. While maintaining the total gas pressure in the closed chamber close to the pressure of the external environment while the cleaning solution is exiting the closed chamber, or
The apparatus of claim 1, further characterized by further comprising gas inlet means for maintaining above it. 23. A reservoir of the selected liquid and a reservoir of the selected liquid which is operated substantially continuously to filter contaminant particles from the selected liquid and to provide a filtration process. The apparatus of claim 1, further comprising liquid filtering means for returning most or all of the later selected liquid to the selected liquid reservoir. 24. Second liquid filtering means connected to said first liquid filtering means for receiving a selected portion of said filtered selected liquid and further filtering the received liquid. , A second reservoir for receiving liquid from the second liquid filtering means, and at least one of a first selected liquid reservoir and a second selected liquid reservoir. Further providing a liquid selected for the vibrating head,
The device according to claim 23. 25. When the device is started after a period of inactivity, all the flow directions of the selected liquid are readjusted for a selected period of time, and after the selected period of time, the selected liquid is selected. A liquid flow deflector for allowing the liquid to flow without interference and a filtering means for receiving and filtering the selected liquid from the flow deflector. 1. The device according to 1. 26. The vibrating head includes a mass of selected solid material that includes a surface that vibrates upon receipt of at least one drop of the selected liquid and that produces atomized particles of the selected liquid. , The selected solid material is adopted from the category of solid material composed of silicon nitride and silicon nitride hydroxide, positioned in contact with the selected solid material mass and connected to an AC voltage source, The device of claim 1, further comprising a piezoelectric crystal that causes the selected mass of solid material to vibrate. 27. A method of performing at least one of a process of drying an object and a process of cleaning an object, the method comprising: placing a selected object to be dried in a closed chamber; Placing a volume of cleaning liquid having a selected surface tension in a closed chamber so that the selected object is partially or fully submerged in the cleaning liquid; Introducing a selected liquid having a low surface tension into the closed chamber at a volume flow rate r2 in the selected volume flow range, and forming atomized particles of the selected liquid in the closed chamber. And a step of allowing a part of the atomized particles to form a film of the selected liquid on the exposed surface of the cleaning liquid, and at a volume flow rate r1 in the selected volume flow range. Draining the cleaning liquid from the closed chamber so that a film of the selected liquid is formed on the exposed surface of the selected object, and the cleaning liquid on the exposed surface of the object selected by the film of the selected liquid. A method of dislodging a. 28. Directing an inert gas in one or more directions toward the atomized particles for movement of the atomized particles in the absence of an inert gas source relative to a selected direction. 28. The method of claim 27, further characterized by moving the spray particles through the chamber in a direction away from the selected direction at an increased angle. 29. The method of claim 27, further characterized by the step of removing at least one of said atomized particles moving within said chamber in said selected direction. 30. The method of claim 27, further characterized by introducing the inert gas at a controllable time-varying gas pressure. 31. The method of claim 30, further comprising the step of varying the time-varying gas pressure to produce a gas pressure that is substantially periodic over time. 32. The step of forming spray particles is further characterized in that a vibrating nozzle oscillating at a selected frequency f in the range of 10 kHz ≦ f ≦ 10,000 kHz is passed through the selected liquid. The method of claim 27. 33. The method of claim 32, further characterized by the step of selecting the frequency f to fall within the range of 20 kHz ≦ f ≦ 80 kHz. 34. The diameter d (sel) of at least one atomized particle is 10 μm.
33. The method of claim 32, further characterized by the step of selecting the frequency f such that it falls within the range <d (sel) <50 [mu] m. 35. The method of claim 27, further characterized by the step of selecting the selected liquid to be substantially chemically unreactive with the selected body. 36. A step of selecting the selected liquid from the category of substantially non-reactive liquids consisting of isopropyl alcohol, ethyl alcohol, methyl alcohol, tetrahydrofuran, acetone, perfluorohexane, hexane, ether. 36. The method of claim 35, further characterized. 37. The depth of the cleaning liquid in the closed chamber is 3 mm / sec and 1
28. The method of claim 27, further characterized by selecting the flow rate r1 to decrease at a rate between 0 mm / sec. 38. The method of claim 27, further characterized by the step of selecting said flow rate r2 such that it is in said second selected range 1 ml / min ≦ r2 ≦ 5 ml / min. 39. The method of claim 27, further comprising forming substantially all of the atomized particles in the closed chamber without changing the phase of the selected liquid. 40. The method further comprising forming the atomized particles in the closed chamber with an energy consumption of less than 2 Joules per second.
7. The method according to 7. 41. The method of claim 27, further comprising the step of removing substantially all gas from the closed chamber after the cleaning liquid has been evacuated from the closed chamber. 42. The method of claim 41, further comprising the step of passing a heated, selected purge gas through the closed chamber after the cleaning liquid has been discharged from the closed chamber. 43. When the cleaning liquid is being discharged from the closed chamber, the cleaning liquid is closed by controlling the flow of the selected replacement gas into the closed chamber and the flow rate of the selected replacement gas into the closed chamber. 28. The method of claim 27, further characterized by the step of causing the total gas pressure in the closed chamber to be close to or above the pressure of the external environment while being evacuated from the chamber. 44. The selected liquid is substantially continuously filtered to remove contaminant particles from the selected liquid, and most or all of the selected liquid after filtration is for the selected liquid. 28. The method of claim 27, further characterized by the step of returning to the reservoir of. 45. Receiving a selected portion of the filtered, selected liquid and further filtering the received liquid, and further filtering the sprayed particles with the selected liquid. 45. The method of claim 44, further characterized by a forming step.