JP2007175559A - High pressure treatment apparatus and high pressure treatment method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high pressure treatment apparatus capable of feeding a high pressure fluid with a high cleanliness to a treatment chamber by preventing a delivery of an unrequired substance captured by a filtration means arranged at a primary side of a treatment chamber to the high pressure fluid, and a high pressure treatment method. <P>SOLUTION: The high pressure treatment apparatus is provided with a main conduit 26 for communicating a high pressure fluid feed unit 2 with a pressure vessel 1 through a filter 24 to lead SCF (high pressure fluid) to the pressure vessel 1; and an opening/closing valve V2 and an opening/closing valve V4 fastened to the main conduit 26 and provided on a primary side and a secondary side of the filter 24 so as to clamp the filter 24. When a cleaning treatment is performed, the opening/closing valves V2, V4 are made in the opened state and the SCF is fed from a high pressure fluid feed unit 2 into the pressure vessel 1. Whereas, when a cleaning treatment is not performed, the opening/closing valves V2, V4 are made in the closed state and the SCF is closed/sealed between the opening/closing valve V2 and the opening/closing valve V4. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a filtered treated fluid obtained by filtering a high-pressure fluid or a mixture of a high-pressure fluid and a drug (additive) by a filtering means, or a filtered high-pressure fluid obtained by filtering a high-pressure fluid by a filtering means and a drug (additive). A high-pressure processing apparatus and a high-pressure processing method for bringing a mixture into contact with the surface of a target object such as a substrate as a processing fluid and performing a predetermined surface treatment (development, cleaning, drying, etc.) on the surface of the target It is about.

  2. Description of the Related Art Conventionally, a technical proposal has been made to perform a high pressure process such as a cleaning process on an object to be processed such as a substrate using a supercritical fluid (hereinafter referred to as “SCF”) having a low viscosity and a high diffusibility as a high pressure fluid. For example, there is a cleaning device that supplies SCF to a processing chamber that accommodates a target object to clean the target object (see Patent Document 1). In this device, by disposing a filter (filtering means) on the primary side of the processing chamber, the filter removes unnecessary substances such as particles contained in the SCF up to a predetermined level required until high-pressure processing is performed. is doing. Then, by supplying SCF to the processing chamber through a filter, the object to be processed is subjected to high pressure processing such as cleaning and removal.

Japanese translation of PCT publication No. 2003-53478 (FIG. 1)

  By the way, when high-pressure processing is performed on the object to be processed, SCF is fed into the processing chamber, and the filter is in a high-pressure state. On the other hand, when loading / unloading from the processing chamber or waiting for the processing operation on the object to be processed, it is necessary to reduce the pressure of the processing chamber to atmospheric pressure. At this time, the filter is also in an atmospheric pressure state (low pressure state). ) Therefore, every time high pressure processing is performed on the object to be processed, the pressure increasing operation and the pressure decreasing operation are repeated for the filter disposed on the primary side of the processing chamber, and the filter is placed in the high pressure state and the low pressure state. It will be.

  On the other hand, the trapping performance of the filter for unwanted substances such as particles greatly depends on the pressure state where the filter is placed, more precisely, the density of the fluid passing through the filter. In general, the trapping performance of the filter tends to improve the trapping efficiency in a low pressure state (low density), and the trapping efficiency is relatively lower in a high pressure state (high density) than in a low pressure state. Therefore, two types of filters, a high-pressure filter suitable for a high-pressure state and a low-pressure filter suitable for a low-pressure state, are provided on the primary side of the processing chamber, and fluid is passed through these two types of filters to increase particle capture efficiency. It is possible to stabilize.

  However, even if two types of filters are arranged in this way, the following problem may occur. That is, if high pressure processing is repeated while replacing the object to be processed in the processing chamber, particles trapped in the filter during pressure increase operation or pressure reduction operation are discharged into the fluid flowing through the filter, and the object to be processed is contaminated. There was a problem. Specifically, for example, by circulating a low-pressure fluid through two types of filters, particles can be captured by the low-pressure filter, but then a high-pressure fluid (high-pressure fluid) is circulated through the low-pressure filter. Then, particles captured by the low pressure filter are discharged into the high pressure fluid in the high pressure state. Such particles are not captured by the high-pressure filter and are sent into the processing chamber together with the high-pressure fluid, resulting in contamination of the object to be processed.

  The present invention has been made in view of the above problems, and prevents high-pressure fluid with high cleanliness by preventing discharge of unnecessary substances trapped by the filtering means disposed on the primary side of the processing chamber to the high-pressure fluid. It is an object of the present invention to provide a high-pressure processing apparatus and a high-pressure processing method that can be supplied to a processing chamber.

  According to the present invention, a high-pressure fluid or a mixture of a high-pressure fluid and a chemical is sent to a processing chamber as a processing fluid, and is brought into contact with the surface of the target object accommodated in the processing chamber to perform a predetermined surface treatment on the surface of the target object In order to achieve the above object, the high-pressure processing apparatus and the high-pressure processing method for applying the above are configured as follows.

  A high-pressure processing apparatus according to the present invention includes a pressure vessel having a processing chamber for performing a surface treatment therein, a high-pressure fluid supply unit capable of pumping high-pressure fluid to the pressure vessel through a filtering unit, and a high-pressure fluid supply unit A flow path control means for controlling the flow path of the high pressure fluid pumped from the flow path, the flow path control means is configured to keep the high pressure fluid filled in the filtration means regardless of the pressure state of the processing chamber. By controlling the above, the filtering means is always kept in a high pressure state. In the high-pressure treatment method according to the present invention, the filtration means is always kept in a high-pressure state by continuously filling the filtration means with the high-pressure fluid regardless of the pressure state of the processing chamber.

  In the invention configured as described above, the filtering means is a high-pressure fluid regardless of the pressure state of the processing chamber, that is, regardless of whether the processing chamber is in a high pressure state such as a supercritical state or a low pressure state such as an atmospheric pressure state. Is always kept in a high pressure state by continuing to be satisfied by. Therefore, even when the pressure increasing operation and the pressure reducing operation are repeated in the processing chamber, unnecessary substances such as particles captured by the filtering means are prevented from being discharged into the high pressure fluid. As a result, a high-pressure fluid having a high cleanliness can be stably supplied to the processing chamber.

  Here, in order to suppress discharge of unnecessary substances such as particles trapped by the filtering means, it may be possible to clean the filtering means before the surface treatment. In such a case, particles adhering to the filtering means may be used. The problem of the removal rate, such as how much can be removed, and the time required to remove particles to a level that does not interfere with the surface treatment, that is, the degradation of the throughput of the apparatus. On the other hand, according to the present invention, it is possible to effectively suppress trapping and discharging of unnecessary substances to the filtering means by always maintaining the filtering means in a high pressure state. Specifically, in the low pressure state (at low density), the particles are easily trapped by the filter medium due to the diffusion of the particles, and the trapping efficiency of the filtering means tends to be improved, but the trapped particles are in the high pressure state ( At high density), it is easily detached from the filter medium and discharged into the high-pressure fluid. On the other hand, the filtration mechanism of the filtering means in the high pressure state (at high density) is not the trapping of the filter medium by the diffusion of the particles, but the trapping of the particles by the voids of the filter medium (particles larger in size than the voids of the filter medium) Cannot pass through and is captured) becomes dominant. Therefore, by holding the filtering means in a high pressure state, it is possible to suppress the trapping of such particles and avoid discharge. Thus, it is inevitable that the filtration mechanism depends on the density of the fluid. However, according to the present invention, if the filtration means continues to be filled with the high-pressure fluid, it may be adversely affected by fluctuations in the fluid density in the filtration means. The problem can be solved. Therefore, the pressure increasing operation and the pressure reducing operation are inevitably repeated, and this is particularly useful in a high pressure processing apparatus in which a gas phase and a supercritical phase (close to liquid density) coexist.

  Here, it is preferable to maintain the filtering means at a pressure state equal to or higher than the process pressure at the time of performing the surface treatment. According to such a configuration, for example, when the processing chamber is depressurized, the filtering means is maintained in a high pressure state equal to or higher than the process pressure when the surface treatment is performed. Therefore, regardless of the pressure state of the processing chamber, the filtering means Can always be maintained at a pressure higher than the process pressure. For this reason, while suppressing the pressure fluctuation of a filtration means and suppressing the discharge of a particle effectively, the capture efficiency of a particle can be stabilized.

  Moreover, the following aspects are mentioned as a concrete means which always maintains a filtration means in a high pressure state irrespective of the pressure state of a processing chamber. That is, as one aspect of the specific means for always maintaining the filtration means in a high pressure state, while performing the surface treatment, while sending the high-pressure fluid to the treatment chamber through the filtration means, while not performing the surface treatment, By sealing the filtering means with a high pressure fluid, the filtering means can always be kept in a high pressure state. Further, as another aspect of the specific means for constantly maintaining the filtering means in a high pressure state, while the surface treatment is being performed, the high-pressure fluid is sent to the processing chamber via the filtering means while the surface treatment is not being performed. By sending the high-pressure fluid to the discharge path for discharging the high-pressure fluid through the filtering means, the filtering means can always be kept in a high-pressure state. That is, the filtering means can always be kept in a high pressure state by continuing to flow the high-pressure fluid through the filtering means.

  Here, as one aspect of the means for always maintaining the filtration means in a high pressure state, when performing the surface treatment, while the high pressure fluid is pumped from the high pressure fluid supply means to the pressure vessel, while the surface treatment is not performed, In an apparatus for stopping the pumping of the high-pressure fluid from the high-pressure fluid supply means, the high-pressure fluid supply means and the pressure vessel communicate with each other via the filtration means, and the main pipeline that guides the high-pressure fluid to the pressure vessel is inserted into the main pipeline. The primary side and secondary side on-off valves are respectively provided on the primary side and secondary side of the filtering means so as to sandwich the filtering means, and when performing surface treatment, the primary side and secondary side on-off valves are provided. Open the high pressure fluid from the high pressure fluid supply means to the pressure vessel, while the surface treatment is not performed, the primary side and secondary side on / off valves are closed with the primary side and secondary side on / off valves closed. The high pressure fluid is sealed between Preferably way. In the apparatus configured as described above, when the surface treatment is performed, the high pressure fluid is fed into the processing chamber through the filtering means, so that the filtering means is maintained in a high pressure state, while the surface treatment is not performed. Even when the pumping of the high-pressure fluid from the high-pressure fluid supply means is stopped, the filtration means is sealed with the high-pressure fluid so that the filtration means is maintained in a high-pressure state regardless of the pressure state of the processing chamber. Can do. Therefore, even when the pressure increase operation and the pressure decrease operation are repeated in the processing chamber by carrying in and out the object to be processed, it is possible to prevent unnecessary substances such as particles captured by the filtering means from being discharged. .

  In addition, the primary side on-off valve is provided between the primary side branch pipe that branches from the main pipe to the primary side and leads to the primary side discharge path that discharges high-pressure fluid, and between the primary side branch pipe and the primary side discharge path. A discharge-side on-off valve that opens and closes the flow path to the primary-side discharge path, and closes the primary-side on-off valve when starting the high-pressure fluid pumping from the high-pressure fluid supply means to the main pipeline. While the discharge side on-off valve is opened and the high-pressure fluid is sent to the primary side branch pipe to increase the pressure in the primary side branch pipe and the primary side on-off valve of the primary side on-off valve, After the pressure in the primary pipe on the primary side of the main pipe reaches the process pressure when the surface treatment is applied, the primary open / close valve is opened and the discharge side open / close valve is closed. Preferably the fluid is fed into the pressure vesselBy configuring in this way, the filtration means is started until the pressure in the main pipe line (primary side of the primary on-off valve) reaches the process pressure after the high-pressure fluid supply means starts to pump the high-pressure fluid to the main pipe line. It can be sealed with a high pressure fluid and kept in a high pressure state. Then, after the pressure in the main pipe line (primary side of the primary side on-off valve) reaches the process pressure, the filtering means can be kept in a high pressure state by feeding high pressure fluid into the filtering means. That is, while the pressure in the main line (primary side on-off valve) is low and the pressure is low, the low-pressure fluid is not circulated to the filtering means, and the primary side branch line is used for the primary side. The pressure in the branch line and the main line (primary side of the primary side on-off valve) is increased so that the high pressure fluid (high pressure fluid) is circulated through the filtering means after reaching the process pressure. Along with this, it is possible to avoid the fluctuation of the pressure state of the filtering means and to keep the filtering means always in a high pressure state.

  Here, in order to increase the pressure in the main pipe line (primary side of the primary side on-off valve) and in the primary side branch pipe, the first pressure adjustment for adjusting the pressure in the primary side branch pipe on the primary side discharge path A valve may be provided. Here, the first pressure regulating valve may be partially opened to increase the process pressure, or the first pressure regulating valve may be closed to increase the process pressure, and then the opening degree is adjusted to adjust the process. The pressure may be maintained at the pressure.

  Furthermore, when sealing the filtering means with the high-pressure fluid, it is preferable to keep the temperature at a desired temperature by the heating means in order to prevent a temperature drop during the standby of the sealed high-pressure fluid.

  Further, as another aspect of the means for constantly maintaining the filtering means in a high pressure state, in an apparatus that continues to pump high pressure fluid from the high pressure fluid supply means, the high pressure fluid supply means and the pressure vessel are communicated with each other via the filtration means. A main pipe that leads the high-pressure fluid to the pressure vessel, a secondary branch pipe that is branched from the main pipe on the secondary side of the filtering means and that leads to a secondary discharge path that discharges the high-pressure fluid, and a secondary branch pipe Switching means for selectively feeding the high-pressure fluid to the pressure vessel and the secondary discharge path by switching the flow path of the high-pressure fluid pumped from the high-pressure fluid supply means. When performing the surface treatment by controlling the switching means, it is preferable to send the high-pressure fluid to the pressure vessel while feeding the high-pressure fluid to the secondary discharge path while not performing the surface treatment. . In the apparatus configured as described above, when the surface treatment is performed, the high pressure fluid is fed into the processing chamber through the filtering means, so that the filtering means is maintained in a high pressure state, while the surface treatment is not performed. By sending the high-pressure fluid to the secondary side discharge path through the filtering means, the filtering means can be kept in a high pressure state. Therefore, even when the pressure increase operation and the pressure decrease operation are repeated in the processing chamber by carrying in and out the object to be processed, it is possible to prevent unnecessary substances such as particles captured by the filtering means from being discharged. .

  Here, the pressure in the main pipe line (primary side of the junction of the secondary branch pipe line and the main pipe line) in which the filtering means is inserted and the pressure in the secondary branch pipe line are always maintained in a high pressure state, that is, the high pressure fluid In order to make it always circulate, the 2nd pressure regulation valve which adjusts the pressure in a secondary side branch pipe line should just be provided on a secondary side discharge course. According to this configuration, by adjusting the opening of the second pressure regulating valve, the pressure in the main pipeline (primary side of the junction between the branch pipeline and the main pipeline) and the secondary branch pipeline is in a high pressure state. For example, the high-pressure fluid can be circulated toward the discharge path (secondary discharge path) while maintaining the process pressure.

  In the present invention, the fluid decompressed by being discharged to the “discharge path” may be collected (and purified if necessary) and reused, or may be discarded outside the system. Good.

  The “surface of the object to be processed” in the present invention means a surface to be subjected to high pressure treatment, and the object to be processed is, for example, a semiconductor wafer, a glass substrate for photomask, a glass substrate for liquid crystal display, or a plasma display. In the case of various substrates such as a glass substrate and an optical disk substrate, when one main surface on which a circuit pattern or the like is formed out of both main surfaces of the substrate needs to be subjected to high pressure treatment, the one main surface Corresponds to the “surface of the object” of the present invention. Moreover, when it is necessary to perform a high pressure process with respect to the other main surface, this other main surface is equivalent to the "surface of a to-be-processed object" of this invention. Of course, when it is necessary to perform high-pressure processing on both main surfaces as in a double-sided mounting substrate, both main surfaces correspond to the “surface of the object to be processed” of the present invention.

  A typical example of the surface treatment in the present invention is a cleaning process for removing and removing contaminants from a target object to which contaminants adhere, such as a semiconductor substrate to which a resist adheres. The object to be processed is not limited to a semiconductor substrate, and includes an object in which a discontinuous or continuous layer of a different substance is formed or remains on various base materials such as metal, plastic, and ceramic. Further, the present invention is not limited to the cleaning process, and all processes (for example, drying, development, etc.) for removing unnecessary substances from the object to be processed using a high-pressure fluid can be targeted by the high-pressure processing apparatus of the present invention. .

  In the present invention, the high-pressure fluid used is preferably carbon dioxide from the viewpoints of safety, cost, and easy supercritical state. In addition to carbon dioxide, water, ammonia, nitrous oxide, ethanol and the like can also be used. The high pressure fluid is used because it has a large diffusion coefficient and can disperse dissolved contaminants in the medium. This is because it becomes possible to penetrate even fine pattern portions. Further, the density of the high-pressure fluid is close to that of a liquid and can contain a much larger amount of additives (drugs) than gas.

  Here, the high-pressure fluid in the present invention is a fluid having a pressure of 1 MPa or more. The high-pressure fluid that can be preferably used is a fluid in which high-density, high-solubility, low-viscosity, and high-diffusibility properties are observed, and more preferable is a fluid in a supercritical state or a subcritical state. In order to use carbon dioxide as a supercritical fluid, the temperature may be 31 ° C. and 7.4 MPa or higher. In the cleaning process, it is preferable to use a subcritical or supercritical fluid having a process pressure of 5 to 30 MPa. More preferably, the treatment is performed at 4 to 30 MPa.

  Moreover, you may make it perform a high pressure process by adding a chemical | medical agent suitably to the high pressure fluid (filtered high pressure fluid) filtered by the filtration means. Alternatively, the high pressure treatment may be performed with a treatment fluid (filtered treatment fluid) obtained by filtering a mixture obtained by appropriately adding a chemical to the high pressure fluid by a filtration means. When adding a chemical to a high-pressure fluid, if the cleaning component as a chemical has low solubility in the high-pressure fluid, use a compatibilizing agent that can aid in dissolving or uniformly dispersing the cleaning component in the high-pressure fluid. Is preferred. In particular, in the case where the drug contains water with respect to the supercritical fluid of carbon dioxide, there are cases where the drug hardly becomes soluble. The compatibilizing agent improves the compatibility between the medicine and the high-pressure fluid when the solubility of the medicine mixed with a plurality of components is poor with respect to the high-pressure fluid used. This compatibilizing agent also has an action of removing the adhered / residual drug in the rinsing process after the cleaning process.

  According to the present invention, regardless of the pressure state of the processing chamber, the filtering means disposed on the primary side of the processing chamber is always kept in a high pressure state by being continuously filled with the high pressure fluid. Therefore, even when the pressure increasing operation and the pressure reducing operation are repeated in the processing chamber, unnecessary substances captured by the filtering means are prevented from being discharged into the high pressure fluid. As a result, a high-purity fluid with a high cleanliness or a mixture of a high-pressure fluid and a chemical can be stably supplied to the processing chamber as a processing fluid.

<First Embodiment>
FIG. 1 is a diagram showing a first embodiment of a high-pressure processing apparatus according to the present invention. FIG. 2 is a block diagram showing an electrical configuration of the high-pressure processing apparatus of FIG. This high-pressure processing apparatus introduces supercritical carbon dioxide as a processing fluid into a processing chamber 11 formed inside the pressure vessel 1, and a substrate such as a substantially circular semiconductor wafer (processing object) held in the processing chamber 11. This is a device that performs a predetermined cleaning process on the body. Hereinafter, the configuration and operation will be described in detail.

  In this high-pressure processing apparatus, a high-pressure fluid supply unit 2 that pumps supercritical carbon dioxide (hereinafter referred to as “SCF”) to the pressure vessel 1 as a “high-pressure fluid” of the present invention, and a high-pressure fluid that is pumped from the high-pressure fluid supply unit 2. The flow path control unit 3 that controls the flow path of the high pressure valves V1 to V4 by opening and closing the pressure control valves PCV1 and PCV2, and the storage section 4 that collects and stores the high-pressure fluid used for the cleaning process. And are provided. Further, a pressure regulating valve PCV 3 is provided between the pressure vessel 1 and the storage unit 4.

  The high-pressure fluid supply unit 2 includes a high-pressure fluid storage tank 21 and a high-pressure pump 22. As described above, when supercritical carbon dioxide is used as the high-pressure fluid, the high-pressure fluid storage tank 21 normally stores liquefied carbon dioxide. Further, the fluid may be cooled in advance by a supercooler (not shown) to prevent gasification in the high-pressure pump 22. If the fluid is pressurized by the high-pressure pump 22, high-pressure liquefied carbon dioxide can be obtained. The outlet side of the high-pressure pump 22 is a main line (high-pressure pipe) 26 including a first heater 23, an on-off valve (high-pressure valve) V 2, a final filter 24, an on-off valve (high-pressure valve) V 4 and a second heater 25. Is connected to the pressure vessel 1. Thus, the on-off valve V2 is disposed on the primary side of the final filter 24 and functions as the “primary-side on-off valve” of the present invention, while the on-off valve V4 is disposed on the secondary side of the final filter 24, It functions as the “secondary opening / closing valve” of the present invention. Then, by opening the on-off valves V2 and V4 in response to an opening / closing command from the controller 8 that controls the entire apparatus, the high-pressure liquefied carbon dioxide pressurized by the high-pressure pump 22 is heated by the first heater 23 and used as a high-pressure fluid. SCF is obtained, and this SCF is filtered by the final filter 24 and directly pumped to the pressure vessel 1. Thereby, unnecessary substances such as particles contained in the SCF are removed, and SCF (filtered SCF) is introduced into the processing chamber 11. Thus, in this embodiment, the final filter 24 functions as the “filtering means” of the present invention. The second heater 25 is provided for heating and heating the high-pressure fluid to supply the high-pressure fluid to the pressure vessel 1 as SCF when the temperature of the high-pressure fluid drops below a predetermined process temperature. Further, the flow path control unit 3 and the controller 8 function as the “flow path control means” of the present invention.

  As the final filter (hereinafter simply referred to as “filter”) 24 disposed on the primary side of the processing chamber 11, it is preferable to use a filter suitable for a high pressure state (high pressure filter). Specifically, a filter suitable for a low-pressure state (low-pressure filter) is configured to easily capture (adsorb) particles on a filter medium by diffusion of particles in a low-pressure state (low density). Although the trapping efficiency tends to improve, the particles trapped in this way are easily detached from the filter medium and discharged into the SCF (high pressure fluid) in a high pressure state (at high density). On the other hand, the high-pressure filter, as its filtration mechanism, instead of trapping the filter medium by the diffusion of particles, trapping particles by the filter medium gap (particles larger than the filter medium gap cannot pass, It is designed to be captured mainly). For this reason, by using a high-pressure filter, it is possible to suppress the capture and discharge of such particles.

  On the other hand, when a low-pressure fluid (for example, gas) and a high-pressure fluid having different densities are circulated using a high-pressure filter, there are the following problems. In other words, particles having a size smaller than the pore size of the filter medium are trapped (adsorbed) by the filter medium in the low pressure state, but they are desorbed when the high pressure state (at high density) is reached and the secondary of the filter. May appear on the side. In some cases, these detached small-sized particles may aggregate and transform into large-sized particles. Therefore, as described later, it is important to keep the filter 24 in a high pressure state to prevent pressure fluctuations in the filter 24.

  Two branch pipes (high-pressure pipes) 27 and 28 are branched from the main pipe line 26. One of these branch lines 27 (corresponding to the “primary side branch line” of the present invention) branches from the main line 26 between the primary heater 23 and the on-off valve V2, more specifically on the primary side of the on-off valve V2. Thus, it is connected to the discharge line 41 (primary discharge path). Between the branch line 27 and the discharge line 41, an on-off valve V1 that opens and closes the flow path to the discharge line 41 is installed as a “discharge-side on-off valve” of the present invention. A pressure regulating valve PCV1 for regulating the pressure in the passage 27 is installed as the “first pressure regulating valve” of the present invention. The discharge line 41 is connected to the storage unit 4, and the SCF discharged to the discharge line 41 is gasified by being depressurized, collected in the storage unit 4, and reused as necessary. Moreover, you may make it discard from the discharge line 41 as it is, without collect | recovering. Note that the on-off valve V1 and the on-off valve V2 are preferably installed in the vicinity of the joint portion between the main pipe line 26 and the branch pipe line 27 and integrated into a block valve. Thereby, it is suppressed that the accumulation of a fluid generate | occur | produces between a junction location and an on-off valve.

  The other branch pipe 28 (corresponding to the “secondary branch pipe” of the present invention) branches from the main pipe 26 between the secondary side of the filter 24, more specifically between the filter 24 and the on-off valve V4. 42 (secondary discharge route). An on-off valve V3 for opening and closing the flow path to the discharge line 42 is installed between the branch line 28 and the discharge line 42, and pressure adjustment for adjusting the pressure in the branch line 28 on the discharge line 42 The valve PCV2 is installed as the “second pressure regulating valve” of the present invention. The discharge line 42 is connected to the storage unit 4 and is collected in the storage unit 4 and reused or discarded from the discharge line 42 as necessary. The on-off valve V3 and the on-off valve V4 are also installed in the vicinity of the junction between the main pipe line 26 and the branch pipe line 28 for the same reason as the on-off valves V1 and V2, and are integrated into a block valve. preferable.

  The pressure vessel 1 is communicated with the storage unit 4 by a high-pressure pipe 5. In addition, a pressure regulating valve PCV3 is inserted in the high-pressure pipe 5. For this reason, when the pressure regulating valve PCV3 is opened, the processing fluid and the like in the pressure vessel 1 are discharged to the storage unit 4, while when the pressure regulating valve PCV3 is closed, the processing fluid can be confined in the pressure vessel 1. It is also possible to adjust the pressure in the processing chamber 11 by opening / closing control of the pressure regulating valve PCV3.

  As the storage unit 4, for example, a gas-liquid separation container or the like may be provided, and the SCF is separated into a gas part and a liquid part using the gas-liquid separation container and discarded through separate paths. Alternatively, each component may be recovered (and purified if necessary) and reused. The gas component and the liquid component separated by the gas-liquid separation container may be discharged out of the system through separate paths.

  Next, the operation of the high-pressure processing apparatus configured as described above will be described with reference to FIGS. FIG. 3 is a timing chart showing the operation of the high-pressure processing apparatus of FIG. FIG. 4 is a diagram schematically showing the operation of the high-pressure processing apparatus of FIG. Here, a case will be described in which the processing chamber 11 is subjected to a cleaning process using a high-pressure fluid as a processing fluid while continuously (or intermittently) replacing a substrate to be processed.

  FIG. 4A shows a state after the cleaning process for the substrate is completed and the substrate is unloaded from the processing chamber 11 while processing is performed while continuously exchanging the substrate. At this time, the filter 24 is sealed with SCF having a pressure equivalent to the process pressure when the substrate is cleaned. Specifically, the on-off valve V2 disposed on the primary side of the filter 24 and the on-off valve V4 disposed on the secondary side of the filter 24 are closed, so that the on-off valve in the main pipeline 26 is closed. The space between V2 and the on-off valve V4 is filled with SCF and maintained in a high pressure state. Furthermore, the inside of the branch conduit 28 is maintained at a high pressure by being filled with SCF. Here, the on-off valve V3 is opened, the pressure regulating valve PCV2 is turned on, and the pressure in the pipe filled with SCF is controlled to be equal to or lower than a predetermined pressure (for example, an abnormal high pressure). In other words, if the pressure in the pipe is less than or equal to the predetermined pressure, the pipe is closed, but if the pressure in the pipe rises for some reason, it can prevent the pipe from rupturing by extracting the pressure in the pipe to the predetermined pressure. Yes. It functions as a substitute for the so-called safety valve. The high pressure valve V1 is closed, and the pressure regulating valves PCV1 and PCV3 are closed with control OFF. The high-pressure pump 22 is also in a stopped state.

  With such a state as an initial state, when an unprocessed substrate is carried into the processing chamber 11 by a handling device such as an industrial robot or a transport mechanism, the processing chamber 11 is closed to complete processing preparation. First, at timing T1, the on-off valve V1 is opened so that the SCF can be pumped from the high-pressure fluid supply unit 2 toward the branch pipe 27, and the pressure adjustment valve PCV1 is set to control ON (pressure adjustment operation is performed) to increase the pressure. The pump 22 is operated. As a result, the SCF is pumped to the branch pipe 27 and the pressure in the branch pipe 27 and the pipe on the primary side of the on-off valve V2 in the main pipe 26 gradually increases (FIG. 4B). ). At this time, the pressure adjustment valve PCV1 may be partially opened and the pressure may be increased to the process pressure. Alternatively, the pressure adjustment valve PCV1 may be closed and the pressure may be increased to the process pressure. May be maintained.

  Thus, while the pressure in the main pipeline 26 (primary side of the on-off valve V2) is low, the low-pressure fluid is prevented from flowing through the filter 24. On the other hand, in order to circulate the high-pressure fluid (SCF) through the filter 24, the pressure in the main pipeline 26 (primary side of the on-off valve V2) is increased using the branch pipeline 27.

  Thus, when the pressure in the main line 26 (primary side of the on-off valve V2) reaches the process pressure (timing T2), the on-off valve V1 is closed while the on-off valve V2 is opened. As a result, the SCF flows toward the branch line 28 through the filter 24, and the pressure in the pipe is maintained at a high pressure state (process pressure) via the pressure regulating valve PCV2 which is controlled ON (partially opened). It is discharged to the discharge line 42 (FIG. 4C). As a result, the SCF around the filter 24 that has not flowed continuously due to sealing is replaced by the SCF newly fed from the high-pressure fluid supply unit 2, and is made accustomed by the flow of SCF. Here, as shown in FIG. 5, a monitoring means 6 for counting the number of particles is provided in-line between the on-off valve V3 and the pressure regulating valve PCV2 in the branch pipe 28, so that the number of particles is stabilized to a predetermined value or less. Until then, the SCF may continue to be discharged to the discharge line 42 via the branch line 28. In addition, when such a break-in process is unnecessary, you may omit.

  At this time, by fully opening the pressure regulating valve PCV1, the SCF in the branch line 27 between the on-off valve V1 and the pressure regulating valve PCV1 is discharged to the discharge line 41 to reduce the pressure in the branch line 27. Keep it. Note that after the pressure in the branch line 27 is reduced, the pressure regulating valve PCV1 is turned off and closed.

  Then, at the next timing T3, the on-off valve V3 is closed and the on-off valve V4 is opened, so that SCF filtered through the filter 24 (filtered SCF) is fed into the pressure vessel 1. At this time, as the on-off valve V4, a pressure regulating valve is used instead of a simple on-off valve, and the valve is gradually opened from the closed state to the open state so that the pressure on the primary side from the on-off valve V4 is not temporarily reduced. May be. Thereby, the pressure drop in the filter 24 can be prevented more reliably. Thus, SCF flows into the processing chamber 11, and the pressure in the processing chamber 11 gradually increases. At this time, the pressure of the processing chamber 11 is kept constant, for example, a process pressure of about 20 MPa, by controlling the pressure regulating valve PCV3 according to an opening / closing command from the controller 8. The pressure adjustment by the opening / closing control is continued until the decompression process described later is completed. Thus, the surface treatment (cleaning treatment) by the SCF is performed on the substrate accommodated in the treatment chamber 11 (FIG. 4D). Further, when it is necessary to adjust the temperature of the processing chamber 11, a temperature suitable for the cleaning process is set by a heater (not shown) provided in the vicinity of the pressure vessel 1.

  In addition, the SCF is sealed in the discharge line 42 between the on-off valve V3 and the pressure adjustment valve PCV2 by closing the pressure adjustment valve PCV2 with control off. That is, the SCF circulated at the timing T2 remains in the discharge line 42 and the discharge line 42 is maintained in a high pressure state. Alternatively, the pressure regulating valve PCV2 may function as a safety valve while the control is ON. Thereby, it is possible to prevent an accident that the SCF sealed in the branch pipe 28 reaches an abnormally high pressure.

  When the substrate cleaning process is thus completed, the on-off valves V2 and V4 are closed to stop the supply of SCF to the pressure vessel 1, and the high-pressure pump 22 is stopped to stop the pumping of SCF (timing T4). Thereby, between the on-off valve V2 and the on-off valve V4 in the main pipeline 26 is maintained in a high pressure state by the SCF. Further, by opening the on-off valve V3 and turning on the pressure regulating valve PCV2, not only the main pipe line 26 between the on-off valve V2 and the on-off valve V4 but also the branch pipe line 28 is filled with SCF and is in a high pressure state. Retained. As a result, the filter 24 is sealed by the SCF and is maintained in a high pressure state. Here, the pressure regulating valve PCV2 controls the pressure in the pipe filled with SCF to be equal to or lower than a predetermined pressure (for example, an abnormal high pressure).

  Further, the SCF in the processing chamber 11 is released to the storage unit 4 through the pressure regulating valve PCV3. That is, the inside of the processing chamber 11 is returned to normal pressure (atmospheric pressure) while controlling the pressure reduction rate by controlling the opening and closing of the pressure regulating valve PCV3. In addition, the SCF in the pipeline on the primary side of the main pipe 26 with respect to the open / close valve V2 opens the open / close valve V1 and discharges to the discharge line 41 through the branch pipe 27 by fully opening the pressure regulating valve PCV1 (see FIG. 4 (e)). As a result, the primary line from the open / close valve V2 and the secondary line (path) from the open / close valve V4 including the processing chamber 11 are returned to normal pressure.

  When the pressure in the path returns to normal pressure, the on-off valve V1 is closed at timing T5, and the pressure regulating valves PCV1, PCV3 are turned off and closed (FIG. 4 (f)). In this way, the same state as shown in FIG. 4A is obtained, and the processed substrate can be replaced with the next unprocessed substrate, the processing chamber 11 is opened, and a handling device such as an industrial robot or a transport mechanism is opened. To carry out the processed substrate. Then, when the next unprocessed substrate is carried in, the above operation is repeated.

  Here, the high-pressure fluid around the filter 24 is held in the pipeline until the next unprocessed substrate is carried in after the completion of the cleaning process. Therefore, as shown in FIG. 6, in order to prevent the temperature of the waiting SCF from decreasing, the high-pressure fluid sealed between the on-off valve V2 and the on-off valve V4 and in the branch pipe 28 in the main pipe line 26 is heated. It is preferable to provide a heating means such as an in-line heater 29 to keep the temperature at a desired temperature. In addition, about the arrangement | positioning position of the inline heater 29, you may be any in the path | route where the high pressure fluid is sealed. Thus, in this embodiment, the in-line heater 29 functions as a “heating means” for heating the sealed high-pressure fluid of the present invention.

  As described above, according to this embodiment, the high-pressure fluid supply unit 2 and the pressure vessel 1 are communicated with each other via the filter 24 to lead the SCF (high-pressure fluid) to the pressure vessel 1, and the main pipeline 26 Are provided on the primary side and the secondary side of the filter 24 so as to sandwich the filter 24, and when performing the cleaning process (surface treatment), the on-off valves V2, V4 are provided. Is opened and SCF is sent from the high-pressure fluid supply unit 2 to the pressure vessel 1, while the cleaning process is not executed, the on-off valves V2 and V4 are closed and the SCF is confined between the on-off valves V2 and V4. It is sealed. For this reason, regardless of whether the processing chamber 11 is in a supercritical state (high pressure state) or an atmospheric pressure state (low pressure state), the filter 24 can be continuously filled with the SCF, and the filter 24 can always be kept in the high pressure state. . Therefore, even when the pressure increasing operation and the pressure decreasing operation are repeated in the processing chamber 11, unnecessary substances such as particles captured by the filter 24 are prevented from being discharged into the SCF. As a result, highly clean SCF can be supplied to the processing chamber 11 and the substrate can be cleaned well.

  Further, according to this embodiment, until the pressure in the main line 26 (primary side of the on-off valve V2) reaches the process pressure from the start of the pressure feeding of the SCF from the high-pressure fluid supply unit 2 to the main line 26, the filter 24 is sealed with SCF and kept in a high pressure state. On the other hand, after the pressure in the main pipe line 26 (primary side of the on-off valve V2) reaches the process pressure, the S24 is fed into the filter 24 to increase the pressure of the filter 24. Held in a state. That is, while the pressure in the main pipe line 26 (primary side of the on-off valve V2) is being increased and the pressure is low, the low-pressure fluid is prevented from flowing through the filter 24, and the branch pipe line 27 is used to make the branch pipe line. 27 and the pressure in the main pipe line 26 (primary side of the on-off valve V2) are increased so that the high-pressure fluid (SCF) flows through the filter 24 after reaching the process pressure. It is possible to keep the filter 24 in a high pressure state by avoiding fluctuations in the pressure state of the 24.

Second Embodiment
FIG. 7 is a diagram showing a second embodiment of the high-pressure processing apparatus according to the present invention. This embodiment is greatly different from the first embodiment. In the first embodiment, the filter 24 is always in a high pressure state by sealing the filter 24 with SCF (high pressure fluid) while the surface treatment is not performed. In contrast, in the second embodiment, the filter 24 is always kept in a high pressure state by passing SCF through the filter 24 even when the surface treatment is not performed. The configuration is basically the same as that of the first embodiment. Therefore, the same components are denoted by the same reference numerals, and the description thereof is omitted. In the following, differences will be mainly described.

  In the second embodiment, the flow path control unit 3 does not have the on-off valve V2 and the branch pipe line 27 (primary side branch pipe line) provided in the first embodiment. Therefore, there is no configuration corresponding to the on-off valve V1, the pressure regulating valve PCV1, and the discharge line 41 provided on the premise of the branch pipe line 27. Therefore, the apparatus configuration is simplified compared to the first embodiment.

  Next, the operation of the high-pressure processing apparatus configured as described above will be described with reference to FIGS. 8 and 9. FIG. 8 is a timing chart showing the operation of the high-pressure processing apparatus of FIG. Moreover, FIG. 9 is a figure which shows typically operation | movement of the high voltage | pressure processing apparatus of FIG. Here, the case where the cleaning process is performed while continuously (or intermittently) exchanging the substrate to be processed with respect to the processing chamber 11 will be described. Note that the SCF continues to be pumped from the high-pressure fluid supply unit 2 by constantly operating the high-pressure pump 22.

  FIG. 9A shows a state in which the cleaning process for the substrate is completed, the processed substrate is unloaded from the processing chamber 11 and the next unprocessed substrate is loaded, or the substrate is loaded into the processing chamber 11 and waits. It shows the state. Here, the on-off valve V3 is opened and the on-off valve V4 is closed, so that the SCF pumped from the high-pressure fluid supply unit 2 flows through the filter 24 toward the branch pipe 28, and the discharge line 42 (secondary side). To the discharge route). The pressure adjustment valve PCV2 is turned on (execution of pressure adjustment operation), and the pressure in the main pipe 26 (primary side of the on-off valve V4) and the branch pipe 28 is maintained in a high pressure state (process pressure). The fluid discharged to the discharge line 42 is depressurized and collected in the storage unit 4 so that it is purified and reused as necessary. Or it is discarded as it is out of the system from the discharge line 41. Then, a cleaning process is performed on the unprocessed substrate with such a state as an initial state. Further, the pressure on the secondary side of the on-off valve V4 is normal pressure, and the pressure regulating valve PCV3 is closed with the control turned off.

  When executing the cleaning process, the on-off valve V4 is opened at the timing T1 and the on-off valve V3 is closed, so that the flow path of the SCF pumped from the high-pressure fluid supply unit 2 is switched and sent to the discharge line 42. SCF was sent to the pressure vessel 1. At this time, as the on-off valve V4, a pressure regulating valve is used instead of a simple on-off valve, and the valve is gradually opened from the closed state to the open state so that the pressure on the primary side from the on-off valve V4 is not temporarily reduced. May be. Thereby, the pressure drop in the filter 24 can be prevented more reliably. In this way, the SCF flows into the processing chamber 11, and the surface treatment (cleaning processing) by the SCF is performed on the substrate accommodated in the processing chamber 11 (FIG. 9B). At this time, the pressure of the processing chamber 11 is kept constant, for example, a process pressure of about 20 MPa, by controlling the pressure regulating valve PCV3 according to an opening / closing command from the controller 8. Thus, in this embodiment, the on-off valves V3 and V4 function as the “switching means” of the present invention.

  At this time, by fully opening the pressure regulating valve PCV2, the SCF in the branch pipe 28 between the on-off valve V3 and the pressure regulating valve PCV2 is discharged to the discharge line 42 to reduce the pressure in the branch pipe 28. Keep it. Alternatively, the pressure regulating valve PCV2 may be left in the control ON state, and the SCF may be sealed to keep the inside of the branch pipe line 28 at a predetermined pressure.

  Thus, when the substrate cleaning process is completed, the on-off valve V3 is opened and the on-off valve V4 is closed, so that the flow path of the SCF pumped from the high-pressure fluid supply unit 2 is switched and sent to the pressure vessel 1. SCF is fed into the discharge line 42 via the branch line 28 (timing T2). At this time, the pressure adjustment valve PCV2 is turned on, and the pressures in the main line 26 (primary side of the on-off valve V4) and the branch line 28 are kept at a high pressure (process pressure). Further, the SCF in the processing chamber 11 is released to the storage unit 4 through the pressure regulating valve PCV3. That is, the process chamber 11 is returned to normal pressure (atmospheric pressure) while controlling the pressure reduction rate by controlling the opening and closing of the pressure regulating valve PCV3 (FIG. 9C).

  Then, when the pressure in the processing chamber 11 returns to normal pressure, the pressure regulating valve PCV3 is controlled to be closed at timing T3 (FIG. 9D). The SCF pumped from the high-pressure fluid supply unit 2 flows through the filter 24 to the branch pipe 28 and continues to be discharged to the discharge line 42. Thus, the same state as shown in FIG. 9A is obtained, and the processed substrate can be replaced with the next unprocessed substrate. The processing chamber 11 is opened and the processed substrate is unloaded. Then, when the next unprocessed substrate is carried in, the above operation is repeated.

  As described above, according to this embodiment, the high-pressure fluid supply unit 2 and the pressure vessel 1 are communicated with each other via the filter 24 to lead the SCF (high-pressure fluid) to the pressure vessel 1 and the filter 24. On the secondary side, the branch line 28 branched from the main line 26 and connected to the discharge line 42 for discharging SCF, and the flow path of the SCF pumped from the high-pressure fluid supply unit 2 are switched so that the SCF is discharged from the pressure vessel 1 and the discharge path. On-off valves V3 and V4 (switching means) that are selectively sent to 28 and control the on-off valves V3 and V4 to send SCF into the pressure vessel 1 when performing a cleaning process (surface treatment). On the other hand, SCF is sent to the discharge line 42 while the cleaning process is not executed. For this reason, regardless of whether the processing chamber 11 is in a supercritical state (high pressure state) or an atmospheric pressure state (low pressure state), the SCF can always flow through the filter 24 and the filter 24 can always be kept in a high pressure state. it can. Therefore, even when the pressure increasing operation and the pressure decreasing operation are repeated in the processing chamber 11, unnecessary substances such as particles captured by the filter 24 are prevented from being discharged into the SCF. As a result, highly clean SCF can be supplied to the processing chamber 11 and the substrate can be cleaned well.

  In addition, according to this embodiment, since the filter 24 is held in a high pressure state while constantly passing SCF through the filter 24, it is possible to avoid stagnation due to SCF retention.

<Others>
The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, in the above-described embodiment, the filter 24 is held at the process pressure when the cleaning process (surface treatment) is performed. However, the present invention is not limited to this, and the filter 24 may be held at a pressure higher than the process pressure. For example, in the second embodiment, when the SCF is fed into the branch pipe 28, the pressure in the main pipe 26 (primary side of the open / close valve V4) and the pressure in the pipe of the branch pipe 28 is larger than the process pressure. The in-pipe pressure may be adjusted by the regulating valve PCV2. Even if comprised in this way, the discharge | emission to the high pressure fluid of the unnecessary substance trapped by the filter 24 can be prevented because the filter 24 is hold | maintained in the high pressure state more than a process pressure.

  In the above embodiment, the substrate cleaning process is executed only by SCF (supercritical carbon dioxide). For example, as shown in FIG. 10, a chemical (additive) containing a cleaning component is added to the SCF. The substrate may be added to perform a cleaning process (third embodiment). Detergency can be increased by using SCF (a mixture of a high-pressure fluid and a drug) to which such a drug is added as a processing fluid. For example, when adding a chemical | medical agent to the high-pressure processing apparatus concerning 1st Embodiment, it can comprise as follows.

  FIG. 10 is a view showing a third embodiment of the high-pressure processing apparatus according to the present invention. This embodiment is different from the first embodiment in that a high-pressure fluid (SCF) for performing a cleaning process is provided with a chemical supply unit 7 for supplying a suitable chemical for removing particles and resist. In other respects, other configurations and operations are the same as those of the first embodiment. Therefore, the following description will focus on the differences.

The medicine supply unit 7 includes a medicine storage tank 72 that stores medicine. As a medicine, it is preferable to use a basic compound as a cleaning component. This is because it has a function of hydrolyzing a polymer substance frequently used in resist and has a high cleaning effect. Specific examples of the basic compound include a quaternary ammonium hydroxide, a quaternary ammonium fluoride, an alkylamine, an alkanolamine, hydroxylamine (NH ₂ OH), and ammonium fluoride (NH ₄ F). One or more selected compounds may be mentioned.

  When the cleaning component such as the basic compound has low solubility in the high-pressure fluid, it is preferable to use a compatibilizing agent that can serve as an auxiliary for dissolving or uniformly dispersing the cleaning component in the high-pressure fluid as the second agent. . This compatibilizing agent also has an effect of preventing dirt from reattaching in the rinsing step after the cleaning step. The compatibilizing agent is not particularly limited as long as the washing component can be compatibilized with the high-pressure fluid, but preferred examples include alcohols such as methanol, ethanol and isopropanol, and alkyl sulfoxides such as dimethyl sulfoxide.

  Further, when cleaning a semiconductor wafer on which a low dielectric constant interlayer insulating film (Low-k film) is formed, a specific amine compound is used in consideration of etching damage to the Low-k film. The amine compound is preferably selected from the group consisting of secondary amines and tertiary amines. More preferably, it is selected from the group consisting of 2- (methylamino) ethanol, PMDETA (pentamethyldiethylenetriamine), triethanolamine, triethylamine, and mixtures thereof. Further, a fluoride representing hydrogen fluoride may be added. Furthermore, a compatibilizer may be added.

  The drug storage tank 72 that stores the drug as described above is connected to the main pipeline 26 by a branch pipeline 71. Specifically, the branch pipe 71 is connected to the main pipe 26 between the on-off valve V4 and the second heater 25. As described above, the chemical is added to the high-pressure fluid on the secondary side of the filter 24, while the corrosion or deterioration of the filter due to the chemical is suppressed, and the high-pressure fluid after the filtration as the unnecessary material is filtered. It is for avoiding mixing in. Further, the chemical is added to the high-pressure fluid on the secondary side of the on-off valve V4 because the high-pressure fluid is confined between the on-off valve V2 and the on-off valve V4 and sealed. This is for avoiding that the liquid is left standing. Further, when the chemical temperature is reduced to less than the process temperature due to the mixing of the chemical by adding the chemical to the high-pressure fluid on the primary side of the second heater 25, the second heater 25 heats the processing fluid to supercritical. It becomes possible to return to a state and to supply to the pressure vessel 1. In addition, even if the chemical | medical agent added to SCF is confined as a process fluid between the on-off valve V2 and the on-off valve V4, when there is no influence on execution of the process in the pressure vessel 1, the 1st heater 23 and the 1st The branch line 71 may be connected to the main line 26 anywhere between the two heaters 25. In any case, the rinsing process using only the SCF is performed after the cleaning process using the mixture of SCF and the drug, so that the drug remains in the pipe between the on-off valve V2 and the on-off valve V4. It will never be done.

  Further, a feed pump 73, a filter 75 (high pressure filter) and a high pressure valve 74 are interposed in the branch pipe 71. The high-pressure valve 74 is preferably installed in the vicinity of the joint between the main pipeline 26 and the branch pipeline 71 and integrated into a block valve. With such a configuration, the opening / closing operation of the high-pressure valve 74 is controlled in accordance with an opening / closing command from the controller 8, whereby the medicine in the medicine storage tank 72 is sent to the main pipeline 26 and the medicine is mixed with the filtered SCF. A processing fluid (SCF + drug) is prepared. Then, the processing fluid is supplied to the processing chamber 11 of the pressure vessel 1.

  Similarly, in the second embodiment, a substrate cleaning process may be executed by adding a chemical (additive) containing a cleaning component to the SCF. In this case, it is preferable to add a chemical | medical agent to the high pressure fluid which distribute | circulates the main pipe line 26 between the filter 24 and the 2nd heater 25 for the reason similar to the above.

  Further, in the above embodiment, the cleaning process is performed as the surface treatment, but the application target of the present invention is not limited to this, for example, receiving a substrate subjected to a development process and a cleaning / rinsing process, The present invention can also be applied to an apparatus that performs only a drying process or a high-pressure processing apparatus that performs another surface treatment (development process or the like).

  In the above embodiment, the present invention is applied to a single wafer processing apparatus that processes the substrates W one by one. However, the present invention is applied to a so-called batch processing apparatus that processes a plurality of substrates W simultaneously. The present invention can also be applied to this.

  Further, in the above embodiment, the high-pressure processing apparatus is provided with the high-pressure fluid supply unit 2, but the present invention is not limited to this, and a high-pressure fluid is supplied from a single high-pressure fluid supply unit to a plurality of high-pressure processing apparatuses. May be. For example, in a large-scale mass production factory, with respect to the high-pressure fluid supply unit 2, the high-pressure fluid supply unit 2 is not provided with one unit for each processing unit, but a single high-pressure fluid supply unit covers a plurality of processing units. You may install a supply part as a factory side utility. Even in such a case, the present application can cope with it suitably.

FIG. 11 is a diagram illustrating a configuration of a high-pressure processing system in which a plurality of high-pressure processing apparatuses are installed. For example, in FIG. 11A, as a factory-side utility, a storage tank 201 as a CO ₂ source, a booster pump 202, a heater 203, and a high-pressure fluid circulation line 204 are installed, and high-pressure fluid (SCF) is circulated under high-pressure fluid. The line 204 is constantly circulated. In the middle of the high-pressure fluid circulation line 204, branch pipes L101, L102,... L10n for supplying SCF to each processing apparatus A1, A2,. The high-pressure fluid circulation line 204 is connected to the first heater 23 installed in each processing apparatus via branch pipes L101, L102,... L10n. The apparatus configuration on the secondary side of the first heater 23 is the same as the apparatus configuration on the secondary side of the first heater 23 in the high-pressure processing apparatus shown in FIGS. 1, 7, and 10. Further, these branch pipes L101, L102,... L10n are open / close valves V101, V102,..., Which control the supply / stop of supply of SCF to the processing devices A1, A2,. V10n is interposed.

In this case, in FIG. 1, FIG. 7, and FIG. 10, the on-off valves V101, V102,..., V10n serve as the high-pressure pump 22 of each processing apparatus, and the ON / OFF operation of the high-pressure pump 22 in each processing apparatus is performed. This corresponds to the opening / closing operation of the on-off valves V101, V102,. Then, the opening / closing valves V101, V102,..., V10n are individually opened / closed by the necessary amount for each processing device A1, A2,. Incidentally, when the amount of CO ₂ storage tank 201 as CO ₂ source by the consumption of CO ₂ is reduced to below a predetermined level, CO ₂ from the outside (not shown) by the supplemented for this reservoir 201.

  In such a high-pressure processing system, since the SCF is constantly circulated, a complicated piping structure must be added even if it is cleaned by backwashing by flowing the SCF in the reverse direction with respect to the filter. . However, according to the said embodiment, SCF with high cleanliness can be supplied to a processing chamber, without changing the form which supplies SCF to each processing apparatus from a circulation line.

Next, FIG. 11B shows still another aspect of the high-pressure processing system in which a plurality of high-pressure processing apparatuses are installed. When the pressure of the high-pressure fluid in the high-pressure fluid circulation line 204 in the factory-side utility is less than the process pressure, it is necessary to increase the fluid to a required process pressure in each of the processing apparatuses A1, A2,. . Therefore, the booster pump 22 is installed on the primary side of the first heater 23 for each of the processing apparatuses A1, A2,. Thus, the fluid supplied from the high-pressure fluid circulation line 204 through the branch pipes L101, L102,... L10n is guided to the booster pump 22 through the on-off valves V101, V102,. It is possible to boost the fluid to the required process pressure. The open / close valves V101, V102,..., V10n are linked to the pumps 22 when the processing devices A1, A2,. Open and close.

  The present invention uses a filtered high-pressure fluid obtained by filtering a high-pressure fluid by a filtering means or a mixture of a filtered high-pressure fluid and a drug (additive) as a processing fluid, and a semiconductor wafer, a glass substrate for a liquid crystal display device, a plasma display panel (PDP)・ High-pressure processing equipment that performs predetermined surface treatments (development treatment, cleaning treatment, drying treatment, etc.) on the surface of objects to be processed, including substrates for display panels and glass substrates and ceramic substrates for magnetic disks Can be applied.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows 1st Embodiment of the high-pressure processing apparatus concerning this invention. It is a block diagram which shows the electrical structure of the high voltage | pressure processing apparatus of FIG. It is a timing chart which shows operation | movement of the high voltage | pressure processing apparatus of FIG. It is a figure which shows typically operation | movement of the high-pressure processing apparatus of FIG. It is a partial block diagram which shows the modification concerning the high-pressure processing apparatus of FIG. It is a partial block diagram which shows the modification concerning the high-pressure processing apparatus of FIG. It is a figure which shows 2nd Embodiment of the high-pressure processing apparatus concerning this invention. It is a timing chart which shows operation | movement of the high voltage | pressure processing apparatus of FIG. It is a figure which shows typically operation | movement of the high-pressure processing apparatus of FIG. It is a figure which shows 3rd Embodiment of the high pressure processing apparatus concerning this invention. It is a figure which shows the structure of the high pressure processing system in which the several high pressure processing apparatus was installed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Pressure vessel 2 ... High pressure fluid supply unit (high pressure fluid supply means)
3 ... Flow path control unit 11 ... Processing chamber 24 ... Filter (filtering means)
26 ... Main pipeline 27 ... Branch pipeline (primary branch pipeline)
28 ... Branch line (secondary branch line)
29 ... In-line heater (heating means)
41 ... Discharge line (primary discharge route)
42 ... Discharge line (secondary discharge route)
V1 ... open / close valve (discharge side open / close valve)
V2 ... Open / close valve (primary open / close valve)
V3 ... Open / close valve (switching means)
V4 ... Open / close valve (secondary open / close valve, switching means)
PCV1 ... Pressure regulating valve (first pressure regulating valve)
PCV2 ... Pressure regulating valve (second pressure regulating valve)

Claims (11)

A high-pressure fluid or a mixture of a high-pressure fluid and a chemical is sent to the processing chamber as a processing fluid, and is brought into contact with the surface of the target object accommodated in the processing chamber to perform a predetermined surface treatment on the surface of the target object. In high pressure processing equipment,
A pressure vessel having a processing chamber for performing the surface treatment therein;
High pressure fluid supply means capable of pumping high pressure fluid to the pressure vessel via filtration means;
Flow path control means for controlling the flow path of the high pressure fluid pumped from the high pressure fluid supply means,
Regardless of the pressure state of the processing chamber, the flow path control means controls the flow path of the high-pressure fluid so that the filtration means continues to be filled with the high-pressure fluid, thereby constantly maintaining the filtration means in a high-pressure state. High pressure processing equipment characterized by.   The high-pressure processing apparatus according to claim 1, wherein the flow path control unit maintains the filtering unit at a pressure state equal to or higher than a process pressure when the surface treatment is performed. When performing the surface treatment, the high-pressure fluid is pumped from the high-pressure fluid supply unit to the pressure vessel, while the high-pressure fluid pumping from the high-pressure fluid supply unit is stopped while the surface treatment is not performed. The high-pressure processing apparatus according to claim 1 or 2,
The flow path control means communicates the high-pressure fluid supply means and the pressure vessel via the filtration means, and guides the high-pressure fluid to the pressure vessel, and is inserted into the main pipeline to pass the filtration means. A primary side on-off valve and a secondary side on-off valve respectively provided on the primary side and the secondary side of the filtering means so as to sandwich,
When performing the surface treatment, while the primary side and secondary side on-off valves are opened, high pressure fluid is sent from the high pressure fluid supply means to the pressure vessel, while the surface treatment is not performed, A high-pressure treatment apparatus that seals a high-pressure fluid between the primary-side on-off valve and the secondary-side on-off valve by closing the primary-side and secondary-side on-off valves. The flow path control means is branched from the main line to the primary side of the primary side on-off valve, and is connected to a primary side discharge path that discharges high-pressure fluid, and the primary side branch line and the primary side A discharge side on-off valve provided between the side discharge path and opening and closing a flow path to the primary side discharge path,
When the high-pressure fluid starts to be fed from the high-pressure fluid supply means to the main pipeline, the primary-side on-off valve is closed and the discharge-side on-off valve is opened to supply the high-pressure fluid to the primary-side branch pipeline. Pressure in the primary side branch pipe and the primary side on / off valve in the primary side of the primary pipe, while the pressure in the primary side of the primary on / off valve in the main pipe 4. The high pressure treatment according to claim 3, wherein after reaching the process pressure when the surface treatment is performed, the primary side on-off valve is opened and the discharge side on-off valve is closed to feed the high-pressure fluid into the pressure vessel. apparatus.   5. The high-pressure processing apparatus according to claim 4, wherein the flow path control unit further includes a first pressure adjusting valve that is provided on the primary-side discharge path and adjusts the pressure in the primary-side branch pipe.   The high-pressure processing apparatus according to any one of claims 3 to 5, further comprising heating means for heating a high-pressure fluid sealed between the primary-side on-off valve and the secondary-side on-off valve. The high-pressure processing apparatus according to claim 1 or 2, wherein the high-pressure fluid continues to be pumped from the high-pressure fluid supply means.
The flow path control means communicates the high-pressure fluid supply means and the pressure vessel via the filtration means to guide the high-pressure fluid to the pressure vessel, and the main pipeline on the secondary side of the filtration means The secondary side branch pipe connected to the secondary side discharge path for discharging the high-pressure fluid and the junction between the secondary side branch pipe and the main pipe, and pumped from the high-pressure fluid supply means Switching means for selectively feeding the high-pressure fluid to the pressure vessel and the secondary discharge path by switching the flow path of the high-pressure fluid,
When the surface treatment is performed by controlling the switching means, the high pressure fluid is fed into the pressure vessel, while the high pressure fluid is fed into the secondary discharge path while the surface treatment is not performed. Processing equipment.   The high-pressure processing apparatus according to claim 7, wherein the flow path control unit further includes a second pressure adjusting valve that is provided on the secondary-side discharge path and adjusts the pressure in the secondary-side branch pipe. A high-pressure fluid or a mixture of a high-pressure fluid and a chemical is sent to the processing chamber as a processing fluid, and is brought into contact with the surface of the target object accommodated in the processing chamber to perform a predetermined surface treatment on the surface of the target object. In the high pressure processing method,
Regardless of the pressure state of the processing chamber, the filtration means is always kept in a high-pressure state by continuously filling the filtration means with a high-pressure fluid.   While performing the surface treatment, the high-pressure fluid is sent to the processing chamber through the filtration means, and while the surface treatment is not performed, the filtration means is sealed with the high-pressure fluid. The high pressure processing method according to claim 9, wherein the pressure is always kept at a high pressure.   While performing the surface treatment, the high-pressure fluid is sent to the processing chamber through the filtering means, and while not performing the surface treatment, the high-pressure fluid is discharged through the filtering means to discharge the high-pressure fluid. The high-pressure processing method according to claim 9, wherein the filtering means is always kept in a high-pressure state by being fed into a path.

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