WO2020231037A1

WO2020231037A1 - Substrate drying chamber

Info

Publication number: WO2020231037A1
Application number: PCT/KR2020/005421
Authority: WO
Inventors: 신희용; 윤병문
Original assignee: 무진전자 주식회사
Priority date: 2019-05-13
Filing date: 2020-04-24
Publication date: 2020-11-19
Also published as: TWI748445B; KR102136691B1; TW202107595A

Abstract

A substrate drying chamber according to the present invention comprises: an upper housing; a lower housing; a substrate placing plate; an upper supply port which provides a supply path for a supercritical fluid for drying; an integrated supply/discharge port which provides a supply path for a supercritical fluid for initial pressurization and a discharge path for a mixed fluid obtained by dissolving an organic solvent in a supercritical fluid for drying after drying is performed by the supply of the supercritical fluid for drying; an agitator which agitates the supercritical fluid for initial pressurization and the supercritical fluid for drying; and a heating member which operates to heat the supercritical fluid for initial pressurization and the mixed fluid when the supercritical fluid for initial pressurization is supplied or the mixed fluid is discharged.

Description

Substrate drying chamber

The present invention relates to a substrate drying chamber. More specifically, the present invention increases the substrate throughput by increasing the mixing speed of the supercritical fluid and the organic solvent, and induces the supercritical fluid to maintain a temperature above the critical point to ensure the uniformity of the drying process. The supercritical fluid for initial pressurization is liquefied or evaporated by the cooling phenomenon due to the pressure drop that occurs during the process of introducing (initial pressurization) into the drying chamber, causing particulate contamination on the substrate, and supercritical drying. When the mixed fluid in which IPA is dissolved in the fluid is discharged (reduced pressure), the mixed fluid phase separates due to the cooling effect, causing particulate contamination on the substrate or collapse of the pattern formed on the substrate due to the surface tension of the mixed fluid. Problems can be solved, and substrate drying efficiency can be increased by inducing a symmetrical flow when supplying and discharging the supercritical fluid, and supplying and discharging the supercritical fluid evenly inside the chamber, and opening the chamber after the drying process is completed. The present invention relates to a substrate drying chamber capable of preventing a problem in which particles are introduced into a substrate inside the chamber.

The semiconductor device manufacturing process includes various processes such as a lithography process, an etching process, and an ion implantation process, and after each process is completed, the surface of the wafer is removed by removing impurities or residues remaining on the wafer surface before proceeding to the next process. A cleaning process and a drying process are being performed for cleaning.

For example, in the cleaning treatment of the wafer after the etching process, a chemical liquid for cleaning treatment is supplied to the surface of the wafer, and then deionized water (DIW) is supplied to perform a rinse treatment. After the rinsing treatment, a drying treatment of drying the wafer by removing deionized water remaining on the wafer surface is performed.

As a method of performing the drying treatment, for example, a technique of drying a wafer by replacing deionized water on a wafer with isopropyl alcohol (IPA) is known.

However, according to such a conventional drying technique, as disclosed in FIG. 1, a problem occurs in that a pattern formed on a wafer is collapsed due to the surface tension of the liquid IPA during the drying process.

In order to solve this problem, a supercritical drying technique in which the surface tension becomes zero has been proposed.

According to this supercritical drying technique, IPA on the wafer is dissolved in the supercritical carbon dioxide (CO ₂ ) fluid by supplying carbon dioxide in a supercritical state to a wafer whose surface is moistened with isopropyl alcohol (IPA) in the chamber. And by gradually discharging the supercritical carbon dioxide (CO ₂ ) fluid dissolving IPA from the chamber, the wafer can be dried without collapse of the pattern.

On the other hand, the supercritical fluid is stored at a high pressure in a supercritical fluid generator provided outside the drying chamber, and then introduced into the drying chamber (initial pressure) while passing through a pipe and a valve, the valve and the pipe connection part. There is a problem in that a cooling phenomenon occurs due to a drop in pressure at, and during this process, it is liquefied or vaporized to cause particulate contamination on the substrate. In particular, when the pressurization speed is increased, there is a problem that sufficient heat transfer to the supercritical fluid is insufficient simply by maintaining the temperature of the pipe through a simple heat exchanger.

In addition, when the mixed fluid in which IPA is dissolved in the drying supercritical fluid for drying is discharged (depressurized) in the drying chamber, if the mixed fluid is phase separated by the cooling effect, it may cause particulate contamination of the substrate or the surface tension of the mixed fluid. As a result, the pattern formed on the substrate may collapse. Specifically, when the temperature and pressure drop below the critical point due to rapid adiabatic expansion in the high pressure region above the critical point, the mixed fluid forming the single phase is phase separated, resulting in poor drying on the substrate. Contamination, etc.), and the pattern collapse of the substrate may also be caused.

FIG. 2 shows a chamber for processing a substrate disclosed in Korean Patent Laid-Open Publication No. 10-2017-0137243, which is a prior art related to a substrate processing apparatus using such a supercritical fluid.

Referring to FIG. 2, in a process of removing IPA in a supercritical drying process, IPA may be introduced into a mating surface of the upper body 430 and the lower body 420 constituting the high-pressure chamber 410 in contact with each other. In this way, the organic solvent introduced into the bonding surface of the upper body 430 and the lower body 420 becomes particles and accumulates around it.

After the supercritical drying process is over, the chamber is opened to transport the processed substrate to the outside. At this time, particles around the bonding surface of the upper body 430 and the lower body 420 are released due to the pressure difference between the inside and the outside of the chamber. It can be introduced into the chamber.

According to Korean Patent Laid-Open Publication No. 10-2017-0137243, since the substrate is located below the bonding surface of the upper body 430 and the lower body 420, the bonding surface of the upper body 430 and the lower body 420 When surrounding particles are introduced into the chamber, there is a high possibility that some of the particles are introduced into the substrate due to gravity.

In this way, since particles flowing into the substrate cause a defect in the process, there is a need to additionally install a blocking film around the bonding surface of the upper body 430 and the lower body 420 in order to prevent particle inflow. Accordingly, there is a problem that the overall structure of the device becomes complicated.

In addition, according to the prior art including Korean Patent Publication No. 10-2017-0137243, a lower supply port 422 for supplying a supercritical fluid for initial pressure, and an exhaust port for exhausting the supercritical fluid after drying ( Since 426 is not located in the center of the lower body 420, it is difficult to supply and discharge the supercritical fluid by evenly distributing the supercritical fluid inside the chamber by forming an asymmetric flow when supplying and discharging the fluid, thereby reducing drying efficiency. A problem occurs.

On the other hand, the mixing speed of the supercritical fluid and IPA supplied in the drying process using the supercritical fluid is one of the important factors affecting the wafer throughput.

In spite of the high dissolving power and fast diffusion rate of the supercritical fluid, according to the prior art including Korean Patent Laid-Open No. 10-2017-0137243, the mixing speed of the supercritical fluid and IPA was not sufficiently increased, resulting in a long drying time. There is a problem that the throughput is reduced.

In addition, such a slow mixing speed has a problem in that it is difficult to maintain the temperature above the critical point of the supercritical fluid, which is disadvantageous in securing the uniformity of the drying process.

[Prior technical literature]

[Patent Literature]

Republic of Korea Patent Publication No. 10-2017-0137243 (published date: December 13, 2017, name: substrate processing apparatus and method)

The technical problem of the present invention is to increase the substrate throughput by increasing the mixing speed of the supercritical fluid and the organic solvent, and induce the supercritical fluid to maintain a temperature above the critical point, thereby securing the uniformity of the drying process. To be able to.

In addition, the technical problem of the present invention is to reduce pressure at the valve and the pipe connection part during the process of introducing (initial pressurization) into the drying chamber through pipes and valves in the supercritical fluid generator provided outside the drying chamber. This is to solve the problem of causing particulate contamination on the substrate by liquefaction or vaporization due to the cooling phenomenon that occurs.

In addition, the technical problem of the present invention is that when the mixed fluid in which IPA is dissolved in the drying supercritical fluid is discharged (reduced pressure) in the drying chamber, the mixed fluid is phase separated by the cooling effect, causing particulate contamination on the substrate. Or the pattern formed on the substrate collapses due to the surface tension of the mixed fluid.

In addition, the technical problem of the present invention is to provide a supply path of the supercritical fluid for initial pressurization and a discharge path of the supercritical fluid in which the organic solvent formed on the substrate after drying is dissolved through one integrated supply/discharge port, thereby providing a supercritical fluid. When supplying and discharging, symmetrical flow is induced, and the supercritical fluid is uniformly distributed in the chamber to supply and discharge, thereby increasing substrate drying efficiency.

In addition, the technical problem of the present invention is to block re-inflow particles when the chamber is opened after the drying process is completed by using a substrate placement plate that is required for arranging a substrate, and initial pressure directed directly to the substrate surface at the beginning of the drying process. It prevents the collapse of the pattern formed on the substrate by preventing the flow of the supercritical fluid for use, and prevents the problem that particles that may be contained in the supercritical fluid for initial pressurization are deposited on the substrate or reduces the amount of deposition, and The drying process time is shortened by reducing the working volume of the chamber due to the volume.

In addition, the technical problem of the present invention is to arrange the substrate on the substrate placement plate so as to be positioned higher than the bonding surface between the lower housing and the upper housing, so that when the drying process is completed and the chamber is opened, Particles around the sealed part are prevented from flowing into the substrate by gravity due to the height difference between the substrate and the bonding surface.

In the substrate drying chamber according to the present invention for solving these technical problems, an upper housing, a lower housing coupled to the upper housing so as to be opened and closed, and a substrate coupled to the bottom surface of the lower housing and formed with an organic solvent are disposed. A substrate arrangement plate, an upper supply port formed in the upper housing so as to face the substrate arrangement plate to provide a supply path of the supercritical fluid for drying, a supply path of the supercritical fluid for initial pressure, and the drying supercritical fluid After drying according to supply, an integrated supply/discharge port providing a discharge path of the mixed fluid in which the organic solvent is dissolved in the supercritical fluid including the initial pressurization supercritical fluid and the drying supercritical fluid, the integrated supply/ An agitator for stirring the initial pressurization supercritical fluid supplied through the discharge port and the drying supercritical fluid supplied through the upper supply port, and is installed on the substrate arrangement plate, and when the initial pressurization supercritical fluid is supplied and And a heating member for heating the initial pressurization supercritical fluid and the mixed fluid by operating when the mixed fluid is discharged.

In the substrate drying chamber according to the present invention, the heating member operates during an initial pressing time in which the initial pressing supercritical fluid is supplied, and controls the temperature of the initial pressing supercritical fluid to be above a critical point. To do.

In the substrate drying chamber according to the present invention, the heating member is operated during a discharge time during which the mixed fluid is discharged, and compensates for a temperature decrease caused by adiabatic expansion due to a pressure drop occurring in the discharge process of the mixed fluid. By doing so, it is characterized in that the temperature of the drying supercritical fluid contained in the mixed fluid is controlled to be above the critical point.

In the substrate drying chamber according to the present invention, the stirrer increases the mixing speed of the organic solvent and the initial pressure supercritical fluid and the mixing speed of the organic solvent and the drying supercritical fluid.

In the substrate drying chamber according to the present invention, the stirrer includes a shaft inserted into the chamber through an insertion hole formed in a central region of the upper housing, and a stirring blade portion coupled to one end located inside the chamber among both ends of the shaft. And a driving unit coupled to the other end located outside the chamber of both ends of the shaft to provide rotational driving force to the shaft.

The substrate drying chamber according to the present invention further includes a shaft coupling member coupled to an outer surface of the upper housing to axially couple a shaft constituting the stirrer, wherein the shaft coupling member is spaced apart from the center point of the shaft coupling member. A plurality of through holes are formed, and the upper supply port comprises a plurality of supply holes formed in the upper housing so as to be aligned with a plurality of through holes formed in the shaft coupling member.

In the substrate drying chamber according to the present invention, a plurality of through holes formed in the shaft coupling member are arranged symmetrically to each other.

In the substrate drying chamber according to the present invention, the integrated supply/discharge port is formed to extend from one side to the other side of the lower housing and is formed to face the substrate arrangement plate in an intermediate region between the one side and the other side. It is characterized by being.

In the substrate drying chamber according to the present invention, the integrated supply/discharge port includes a first conduit part formed from one side of the lower housing to the middle region, and the substrate is disposed in communication with the first conduit part in the intermediate region. And a second conduit portion formed to face the plate and communicated with the common port portion and the first conduit in the intermediate region to the other side of the lower housing.

In the substrate drying chamber according to the present invention, the first pipe part and the common port part provide a supply path of the supercritical fluid for initial pressure, and the common port part and the second pipe part It is characterized in that it provides a discharge path of the critical fluid.

The substrate drying chamber according to the present invention further includes a sealing portion provided on a bonding surface between the lower housing and the upper housing, and the substrate is positioned higher than the bonding surface between the lower housing and the upper housing. And when the drying process is completed and the lower housing and the upper housing are opened, particles around the sealing portion provided on the bonding surface are transferred to the substrate by gravity according to the height difference between the substrate and the bonding surface. It is characterized in that the inflow of is prevented.

In the substrate drying chamber according to the present invention, the supercritical fluid for initial pressure supplied through the first conduit portion and the common port portion is blocked by the substrate arrangement plate so that direct injection to the substrate is prevented.

In the substrate drying chamber according to the present invention, one end is coupled to the bottom surface of the lower housing and the other end is coupled to the substrate placement plate, thereby supporting the substrate placement plate while separating the substrate placement plate from the bottom surface of the lower housing. It characterized in that it further comprises a substrate arrangement plate support.

In the substrate drying chamber according to the present invention, the first spaced space existing between the bottom surface of the lower housing and the substrate placement plate by the substrate placement plate support part is for initial pressure supplied through the integrated supply/discharge port. It is characterized in that the supercritical fluid moves along the lower surface of the substrate arrangement plate to gradually diffuse into the processing area in which the substrate is disposed.

The substrate drying chamber according to the present invention further includes a substrate support portion having one end coupled to the upper surface of the substrate arrangement plate and the other end coupled to the substrate, supporting the substrate and separating the substrate from the upper surface of the substrate arrangement plate Characterized in that.

In the substrate drying chamber according to the present invention, the second separation space existing between the upper surface of the substrate arrangement plate and the substrate by the substrate support portion is an initial pressurization supplied to the lower surface of the substrate through the integrated supply/discharge port. It is characterized in that the drying process is shortened by exposure to the supercritical fluid for drying and the supercritical fluid for drying supplied through the upper supply port.

According to the present invention, it is possible to increase the substrate throughput by increasing the mixing speed of the supercritical fluid and the organic solvent, and induce the supercritical fluid to maintain a temperature above the critical point, thereby securing the uniformity of the drying process. have.

According to the present invention, the supercritical fluid is introduced into the drying chamber through pipes and valves in the supercritical fluid generator provided outside the drying chamber (initial pressurization). There is an effect of solving the problem of causing particle contamination on the substrate by being liquefied or vaporized by the cooling phenomenon.

In addition, when the mixed fluid in which IPA is dissolved in the drying supercritical fluid is discharged (depressurized) in the drying chamber, the mixed fluid is phase separated by the cooling effect, causing particulate contamination on the substrate or the surface tension of the mixed fluid. There is an effect of solving the problem that the pattern formed on the substrate collapses.

In addition, by providing the supply path of the supercritical fluid for initial pressurization and the discharge path of the supercritical fluid in which the organic solvent formed on the substrate after drying is dissolved through one integrated supply/discharge port, it is symmetrical when supplying and discharging the supercritical fluid. The supercritical fluid is uniformly distributed and supplied and discharged in the chamber by inducing a natural flow, thereby increasing substrate drying efficiency.

In addition, by using a substrate placement plate that is required for arranging the substrate, it blocks re-inflow particles when the chamber is opened after the drying process is completed, and the initial pressure supercritical fluid flows directly to the substrate surface at the beginning of the drying process. It is possible to prevent the collapse of the pattern formed on the substrate, prevent the problem that particles that may be contained in the initial pressurization supercritical fluid are deposited on the substrate, or reduce the amount of deposition, and reduce the amount of deposition. Due to the reduced working volume of the chamber there is an effect of shortening the drying process time.

In addition, by placing the substrate on the substrate mounting plate so as to be positioned higher than the bonding surface between the lower housing and the upper housing, when the drying process is completed and the chamber is opened, particles around the sealing portion provided on the bonding surface between the lower housing and the upper housing There is an effect of preventing a problem from flowing into the substrate due to gravity due to a height difference between the substrate and the bonding surface.

1 is a diagram showing a pattern collapse phenomenon occurring in a substrate drying process according to the prior art,

2 is a view showing a conventional substrate drying chamber,

3 is a view showing a substrate drying chamber according to an embodiment of the present invention,

4 is a view showing an exemplary top surface shape in which a shaft constituting a stirrer is coupled to a shaft coupling member in an embodiment of the present invention,

5 is a view showing a diffusion path of the initial pressurization supercritical fluid in an embodiment of the present invention,

6 is a diagram showing a diffusion path of a drying supercritical fluid in an embodiment of the present invention,

7 is a view showing a discharge path of a mixed fluid in which an organic solvent is dissolved in a supercritical fluid including an initial pressurizing supercritical fluid and a drying supercritical fluid in an embodiment of the present invention,

FIG. 8 is a diagram illustrating a sealing portion provided on a bonding surface between the upper housing and the lower housing and a substrate of particles existing therearound when the drying process is completed and the lower housing and the upper housing are opened, according to an embodiment of the present invention. It is a diagram for explaining the principle of preventing the inflow of

Specific structural or functional descriptions of the embodiments according to the concept of the present invention disclosed in the present specification are only exemplified for the purpose of describing the embodiments according to the concept of the present invention, and the embodiments according to the concept of the present invention are in various forms. And are not limited to the embodiments described herein.

Since the embodiments according to the concept of the present invention can apply various changes and have various forms, embodiments are illustrated in the drawings and will be described in detail in the present specification. However, this is not intended to limit the embodiments according to the concept of the present invention to specific disclosed forms, and includes all changes, equivalents, or substitutes included in the spirit and scope of the present invention.

Terms such as first or second may be used to describe various elements, but the elements should not be limited by the terms. The terms are only for the purpose of distinguishing one component from other components, for example, without departing from the scope of the rights according to the concept of the present invention, the first component may be named as the second component and similarly the second component. The component may also be referred to as a first component.

When a component is referred to as being "connected" or "connected" to another component, it should be understood that it is directly connected or may be connected to the other component, but other components may exist in the middle. will be. On the other hand, when a component is referred to as being "directly connected" or "directly connected" to another component, it should be understood that there is no other component in the middle. Other expressions describing the relationship between components, such as "between" and "directly between" or "adjacent to" and "directly adjacent to" should be interpreted as well.

The terms used in the present specification are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In the present specification, terms such as "comprise" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described herein, but one or more other features. It is to be understood that the possibility of addition or presence of elements or numbers, steps, actions, components, parts, or combinations thereof is not preliminarily excluded.

Unless otherwise defined, all terms, including technical or scientific terms, used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Terms as defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and should not be interpreted as an ideal or excessively formal meaning unless explicitly defined herein .

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a view showing a substrate drying chamber according to an embodiment of the present invention, and FIG. 4 is an exemplary top shape in which a shaft constituting a stirrer is coupled to a shaft coupling member in an embodiment of the present invention. 5 is a view showing the diffusion path of the initial pressurization supercritical fluid in an embodiment of the present invention, and FIG. 6 is a view showing the diffusion of the drying supercritical fluid in an embodiment of the present invention. FIG. 7 is a diagram showing a path, and FIG. 7 is a view showing a discharge path of a mixed fluid in which an organic solvent is dissolved in a supercritical fluid including a supercritical fluid for initial pressurization and a supercritical fluid for drying in an embodiment of the present invention 8 is, in one embodiment of the present invention, when the drying process is completed and the lower housing and the upper housing are opened, the sealing portion provided on the bonding surface of the upper housing and the lower housing and particles existing therearound It is a diagram for explaining the principle of preventing inflow to the substrate.

3 to 8, a substrate drying chamber 1 according to an embodiment of the present invention includes an upper housing 10, a lower housing 20, a sealing unit 30, a substrate placement plate 40, and heating. The member 45, the integral supply/discharge port 50, the upper supply port 60, the substrate plate support part 70, the substrate support part 80, the housing drive part 90, the stirrer 100, and the shaft coupling member ( 200).

The upper housing 10 and the lower housing 20 are coupled to each other so as to be able to open and close, and provide a space in which a drying process is performed. For example, the upper housing 10 and the lower housing 20 may be configured to have a cylindrical shape, but are not limited thereto. As will be described later, an upper supply port 60 is formed in the upper housing 10, and an integrated supply/discharge port 50 is formed in the lower housing 20. The specific configuration of the upper supply port 60 will be described in detail later in connection with the configuration of the stirrer 100 and the shaft coupling member 200.

The sealing part 30 is provided on the coupling surface (C) of the lower housing 20 and the upper housing 10, and maintains the airtightness of the coupling surface (C) between the lower housing 20 and the upper housing 10. Block the inner area of the chamber from the outside.

For example, when the drying process is completed and the lower housing 20 and the upper housing 10 are opened, the sealing part 30 provided on the coupling surface C of the upper housing 10 and the lower housing 20 And, as illustrated in FIG. 8 for explaining the principle of preventing the inflow of particles existing in the vicinity to the substrate W, the substrate W is a bonding surface of the lower housing 20 and the upper housing 10 When the lower housing 20 and the upper housing 10 are opened when the drying process is completed and the lower housing 20 and the upper housing 10 are opened, the sealing part provided on the bonding surface (C) (30) The surrounding particles may be configured to be prevented from entering the substrate W by gravity according to a height difference between the substrate W and the bonding surface C.

The substrate arranging plate 40 is a component on which a substrate W on which an organic solvent is formed is attached to the bottom surface 22 of the lower housing 20. The interaction between the substrate arrangement plate 40 and other components will be described later.

The heating member 45 is installed on the substrate arranging plate 40 and operates when the supercritical fluid for initial pressurization is supplied and when the mixed fluid is discharged to heat the supercritical fluid for initial pressurization and the mixed fluid. do.

For example, the heating member 45 may be implemented in the form of an electric resistance heating element or an oil-filled heater formed in the substrate mounting plate 40, but the implementation form of the heating member 45 is It is not limited thereto.

For example, 1) the initial pressure supercritical fluid is supplied during the set initial pressure time through the first conduit portion 510 and the common port portion 520 constituting the integrated supply/discharge port 50, and 2) After the initial pressurization time has elapsed, the supply of the initial pressurization supercritical fluid is cut off, and the drying supercritical fluid is supplied through the upper supply port 60 for the drying time, and 3) the drying supercritical fluid is after the drying time. The supply of the fluid is blocked and the mixed fluid may be discharged during the discharge time through the common port part 520 and the second conduit part 530 constituting the integrated supply/discharge port 50. In this case, for example, the supply of the drying supercritical fluid and the discharge of the mixed fluid may be repeated a set number of times.

For example, the heating member 45 may be operated during an initial pressing time during which the initial pressing supercritical fluid is supplied, so that the temperature of the initial pressing supercritical fluid may be adjusted to be above a critical point.

The reason for this configuration and its effect will be described as follows.

The supercritical fluid is stored at a high pressure in a supercritical fluid generator provided outside the substrate drying chamber 1 according to an embodiment of the present invention, and then passed through a pipe and a valve to the substrate drying chamber 1. During the process of introduction (initial pressurization), a cooling phenomenon occurs due to a pressure drop at the connection portion of the valve and the pipe, and during this process, the temperature may be liquefied or vaporized to cause particulate contamination on the substrate W. It is important to maintain it, but the prior art has not provided an effective technical measure for this. In particular, when the pressurization speed is increased, there is a problem that sufficient heat transfer to the supercritical fluid is insufficient simply by maintaining the temperature of the pipe through a simple heat exchanger.

An embodiment of the present invention solves this problem through the heating member 45 installed on the substrate mounting plate 40. That is, the initial pressurization through the heating member 45 installed on the substrate arranging plate 40 in the chamber, especially when the initial pressurization proceeds rapidly, minimizes the phase change of the supercritical fluid for initial pressurization in the substrate drying chamber 1 W) particle contamination can be prevented, and the process speed can be improved by facilitating formation or maintenance of a supercritical fluid.

In addition, for example, the heating member 45 is operated during the discharge time during which the mixed fluid is discharged, and compensates for the temperature decrease caused by the adiabatic expansion due to the pressure drop occurring in the discharge process of the mixed fluid, The temperature of the supercritical fluid for drying included in can be adjusted to be above the critical point.

The reason for this configuration and its effect will be described as follows.

When the mixed fluid in which an organic solvent such as IPA is dissolved in the drying supercritical fluid in the chamber is discharged (reduced pressure), when the mixed fluid is phase separated by the cooling effect, particulate contamination or mixed fluid of the substrate (W) The pattern formed on the substrate W may collapse due to the surface tension of. Specifically, when the temperature and pressure drop below the critical point due to rapid adiabatic expansion in the high pressure region above the critical point, the mixed fluid constituting the single phase is phase separated, resulting in poor drying on the substrate (W). (Particulate contamination, etc.) may be caused, and pattern collapse of the substrate W may also be caused.

An embodiment of the present invention solves this problem through the heating member 45 installed on the substrate mounting plate 40. That is, when the mixed fluid is discharged, the decompression rate is considered in consideration of the phase change, and the heating member 45 is used to transfer sufficient heat to proceed with the decompression discharge step in consideration of the cooling effect, thereby preventing drying failure and speeding up the process. It can be improved.

For example, the initial pressure supercritical fluid supplied through the first conduit portion 510 and the common port portion 520 constituting the integrated supply/discharge port 50 is blocked by the substrate mounting plate 40 and thus the substrate ( It can be configured to prevent direct injection to W).

More specifically, Figure 5 shows the diffusion path of the initial pressurization supercritical fluid, and the diagram showing the discharge path of the mixed fluid in which an organic solvent is dissolved in the supercritical fluid including the initial pressurization supercritical fluid and the drying supercritical fluid. As illustrated in 7, using the substrate placement plate 40 required to arrange the substrate W, which is the target of the drying process, after the drying process is completed, when the chamber is opened, re-inflow particles are blocked, and the drying process It is possible to prevent the collapse of the pattern formed on the substrate (W) by preventing the flow of the initial pressure supercritical fluid directly to the surface of the substrate (W), and particles that may be contained in the initial pressure supercritical fluid are contained on the substrate. It is possible to prevent the problem of depositing on the (W) or to reduce the amount of deposition, and to reduce the working volume of the chamber due to the volume occupied by the substrate arrangement plate 40 to shorten the drying process time.

The integrated supply/discharge port 50 is formed extending from one side 24 to the other side 26 of the lower housing 20, and the substrate is arranged in the intermediate region 28 between one side 24 and the other side 26. Discharge of the mixed fluid dissolved in the initial pressure supercritical fluid and the drying supercritical fluid formed on the substrate (W) after drying and the supply path of the supercritical fluid for initial pressure, formed to face the plate 40 It is a component that provides a path.

The supply path of the supercritical fluid for initial pressurization and the organic solvent formed on the substrate W after drying are dissolved in the supercritical fluid for initial pressurization and the supercritical fluid for drying through one such integrated supply/discharge port 50 By providing a discharge path of the fluid, there is an effect of increasing the substrate drying efficiency by inducing a symmetrical flow when supplying and discharging the supercritical fluid and supplying and discharging the supercritical fluid evenly in the chamber.

For example, such an integrated supply/discharge port 50 has a first conduit portion 510 formed from one side 24 of the lower housing 20 to the middle region 28, and the first conduit portion 510 in the middle region 28. The lower housing is in communication with the conduit part 510 and is in communication with the common port part 520 and the first conduit part 510 in the common port part 520 and the intermediate region 28 formed to face the substrate mounting plate 40. It includes a second conduit part 530 formed up to the other side 26 of 20, and the first conduit part 510 and the common port part 520 provide a supply path of the supercritical fluid for initial pressurization, The common port part 520 and the second conduit part 530 may be configured to provide a discharge path for the supercritical fluid in which the organic solvent is dissolved.

The upper supply port 60 is a component formed to face the substrate mounting plate 40 in the central region of the upper housing 10 to provide a supply path of the supercritical fluid for drying.

For example, 1) the initial pressure supercritical fluid is supplied during the set initial pressure time through the first conduit portion 510 and the common port portion 520 constituting the integrated supply/discharge port 50, and 2) After the initial pressurization time has elapsed, the supply of the initial pressurization supercritical fluid is cut off, and the drying supercritical fluid is supplied through the upper supply port 60 for the drying time, and 3) the drying supercritical fluid is after the drying time. The supply of the fluid is blocked and the mixed fluid may be discharged during the discharge time through the common port part 520 and the second conduit part 530 constituting the integrated supply/discharge port 50. In this case, for example, the supply of the supercritical fluid for drying and the discharge of the mixed fluid may be repeated a set number of times, that is, flushed.

The agitator 100 is a component that agitates the initial pressure supercritical fluid supplied through the integrated supply/discharge port and the drying supercritical fluid supplied through the upper supply port in the chamber. It can be configured to increase the mixing speed of the critical fluid and the mixing speed of the organic solvent and the drying supercritical fluid. According to this configuration, it is possible to increase the substrate throughput, which is a performance indicator of the supercritical drying process, and induce the supercritical fluid to maintain a temperature above the critical point, thereby ensuring uniformity in the drying process.

For example, as illustrated in FIGS. 3 and 4, the stirrer 100 may include a shaft 110, a stirring blade 120, and a driving part 130.

The shaft 110 is a component inserted into the chamber through an insertion hole formed in the central region of the upper housing, and performs a function of rotating by a rotational driving force provided by the driving unit 130.

The stirring blade unit 120 is a component coupled to one end located inside the chamber among both ends of the shaft 110, and performs a function of agitating the supercritical fluid by rotating inside the chamber according to the rotation of the shaft 110. .

The driving unit 130 is a component that is coupled to the other end located outside the chamber of both ends of the shaft 110 to provide rotational driving force to the shaft 110.

The shaft coupling member 200 is a component that is coupled to the outer surface of the upper housing to axially couple the shaft 110 constituting the stirrer 100.

For example, as illustrated in FIG. 4, in the shaft coupling member 200, a plurality of through

holes

210, 220, 230, 240 spaced apart from the center point of the shaft coupling member 200 are formed symmetrically. It may be configured, and the upper supply port may be formed of a plurality of supply holes formed in the upper housing so as to be aligned in the vertical direction with a plurality of through holes formed in the shaft coupling member 200. Of course, in the central region of the shaft coupling member 200, a hole arranged in the vertical direction is formed in the insertion hole formed in the upper housing, and the hole formed in the central region of the shaft coupling member 200 constituting the stirrer 100 It can be inserted into the chamber through the insertion hole formed in the upper housing, the shaft coupling member 200 through which the shaft 110 passes may be provided with a bearing (bearing) means.

The substrate placement plate support part 70 has one end coupled to the bottom surface 22 of the lower housing 20 and the other end coupled to the substrate placement plate 40, and supports the substrate placement plate 40 while supporting the substrate placement plate ( It is a component that separates 40) from the bottom surface 22 of the lower housing 20.

For example, the first spaced space R1 existing between the bottom surface 22 of the lower housing 20 and the substrate placement plate 40 by the substrate placement plate support part 70 is an integral supply/discharge port 50 The supercritical fluid for initial pressure supplied through) may move along the lower surface of the substrate placement plate 40 to gradually diffuse into the processing area where the substrate W is disposed.

The substrate support 80 has one end coupled to the upper surface of the substrate placement plate 40 and the other end coupled to the substrate W. While supporting the substrate W, the substrate W is attached to the upper surface of the substrate placement plate 40. It is a component that separates from

For example, the second separation space R2 existing between the upper surface of the substrate mounting plate 40 and the substrate W by the substrate support 80 provides the lower surface of the substrate W as the integrated supply/discharge port ( It performs a function of shortening the drying process time by exposure to the initial pressure supercritical fluid supplied through 50) and the drying supercritical fluid supplied through the upper supply port 60.

The housing driving unit 90 is a means for opening and closing the housing, and after the drying process is completed, the lower housing 20 is driven to separate the lower housing 20 from the upper housing 10 to open the chamber or initiate the drying process. In this case, the lower housing 20 may be driven to couple the lower housing 20 to the upper housing 10 to close the chamber. In the drawings, the housing driving unit 90 is expressed as driving the lower housing 20, but this is only an example, and the housing driving unit 90 may be configured to drive the upper housing 10.

For example, the supercritical fluid for initial pressurization and the supercritical fluid for drying may include carbon dioxide (CO ₂ ), and the organic solvent may include alcohol, but is not limited thereto. As a specific example, the alcohol may include methanol, ethanol, 1-propanol, 2-propanol, IPA, and 1-butanol. It is not limited.

For example, according to the supercritical drying technique performed in the substrate drying chamber according to an embodiment of the present invention, carbon dioxide in a supercritical state is applied to the substrate W whose surface is moistened with an organic solvent such as alcohol in the chamber. By supplying, the alcohol on the substrate W is dissolved in the supercritical carbon dioxide fluid. In addition, by gradually discharging the supercritical carbon dioxide fluid in which alcohol is dissolved from the chamber, the substrate W can be dried without collapse of the pattern.

As described in detail above, according to the present invention, in the process of introducing (initial pressure) into the drying chamber through pipes and valves in the supercritical fluid generator provided outside the drying chamber, the valve and the pipe connection portion There is an effect of solving the problem of causing particulate contamination on the substrate by being liquefied or vaporized by a cooling phenomenon caused by a pressure drop.

In addition, by increasing the mixing speed of the supercritical fluid and the organic solvent, the substrate throughput is increased, and the supercritical fluid maintains a temperature above the critical point, thereby securing the uniformity of the drying process. have.

[Explanation of code]

1: substrate drying chamber

10: upper housing

20: lower housing

22: bottom surface

24: one side

26: the other side

28: middle area

30: sealing part

40: substrate placement plate

45: heating member

50: Integrated supply/discharge port

60: upper supply port

61, 62: supply hole

70: substrate arrangement plate support

80: substrate support

90: housing drive

100: stirrer

110: shaft

120: stirring blade portion

130: drive unit

200: shaft coupling member

210, 220, 230, 240: through hole

510: first pipeline

520: common port part

530: second pipeline

C: bonding surface

R1: first separation space

R2: second separation space

W: substrate

Claims

Upper housing;

A lower housing coupled to the upper housing to be opened and closed;

A substrate mounting plate coupled to a bottom surface of the lower housing and on which a substrate on which an organic solvent is formed is disposed;

An upper supply port formed in the upper housing so as to face the substrate arrangement plate to provide a supply path of the supercritical fluid for drying;

Mixing of the organic solvent dissolved in the supercritical fluid including the initial pressure supercritical fluid and the drying supercritical fluid after drying according to the supply path of the initial pressure supercritical fluid and the supply of the drying supercritical fluid An integrated supply/discharge port providing a fluid discharge path;

A stirrer for stirring the initial pressure supercritical fluid supplied through the integrated supply/discharge port and the drying supercritical fluid supplied through the upper supply port; And

Drying the substrate, which is installed on the substrate arrangement plate and includes a heating member for heating the initial pressure supercritical fluid and the mixed fluid by operating at the time of supplying the initial pressure supercritical fluid and discharging the mixed fluid chamber.
The method of claim 1,

The heating member,

The substrate drying chamber, characterized in that operating during an initial pressing time in which the initial pressing supercritical fluid is supplied, and controlling the temperature of the initial pressing supercritical fluid to be above a critical point.
The method of claim 1,

The heating member,

The temperature of the drying supercritical fluid contained in the mixed fluid is operated during the discharge time during which the mixed fluid is discharged, and compensates for the temperature decrease caused by the adiabatic expansion due to the pressure drop occurring in the discharge process of the mixed fluid. A substrate drying chamber, characterized in that it is adjusted to be above the critical point.
The method of claim 1,

The stirrer,

A substrate drying chamber, characterized in that increasing the mixing speed of the organic solvent and the initial pressure supercritical fluid and the mixing speed of the organic solvent and the drying supercritical fluid.
The method of claim 4,

The stirrer,

A shaft inserted into the chamber through an insertion hole formed in the central region of the upper housing;

Agitation blades coupled to one end located inside the chamber among both ends of the shaft; And

And a driving unit coupled to the other end positioned outside the chamber of both ends of the shaft to provide rotational driving force to the shaft.
The method of claim 5,

Further comprising a shaft coupling member coupled to the outer surface of the upper housing to shaft-couple the shaft constituting the stirrer,

The shaft coupling member has a plurality of through holes spaced apart from the center point of the shaft coupling member,

The upper supply port,

A substrate drying chamber comprising a plurality of supply holes formed in the upper housing so as to be aligned with a plurality of through holes formed in the shaft coupling member.
The method of claim 6,

A substrate drying chamber, characterized in that a plurality of through-holes formed in the shaft coupling member are arranged symmetrically to each other.
The method of claim 1,

The integrated supply/discharge port,

The substrate drying chamber, characterized in that the substrate drying chamber is formed to extend from one side of the lower housing to the other side and is formed to face the substrate arrangement plate in an intermediate region between the one side and the other side.
The method of claim 8,

The integrated supply/discharge port,

A first conduit formed from one side of the lower housing to the intermediate region;

A common port part formed to face the substrate arrangement plate in communication with the first conduit part in the intermediate region; And

And a second conduit connected to the common port part and the first conduit part in the intermediate region and formed to the other side of the lower housing.
The method of claim 9,

The first conduit portion and the common port portion provide a supply path for the initial pressurization supercritical fluid,

The common port portion and the second conduit portion, characterized in that providing a discharge path of the supercritical fluid in which the organic solvent is dissolved, the substrate drying chamber.
The method of claim 10,

Further comprising a sealing portion provided on the coupling surface of the lower housing and the upper housing,

The substrate is disposed on the substrate mounting plate so as to be positioned higher than the bonding surface between the lower housing and the upper housing, and when the drying process is completed and the lower housing and the upper housing are opened, sealing provided on the bonding surface A substrate drying chamber, characterized in that the inflow of particles around the part into the substrate is prevented by gravity according to a height difference between the substrate and the bonding surface.
The method of claim 11,

A substrate drying chamber, characterized in that the initial pressure supercritical fluid supplied through the first conduit portion and the common port portion is blocked by the substrate arrangement plate to prevent direct spraying to the substrate.
The method of claim 1,

One end is coupled to the bottom surface of the lower housing and the other end is coupled to the substrate placement plate, further comprising a substrate placement plate support part that supports the substrate placement plate and separates the substrate placement plate from the bottom surface of the lower housing. Characterized in that, the substrate drying chamber.
The method of claim 13,

The first spaced space existing between the bottom surface of the lower housing and the substrate placement plate by the substrate placement plate support part is a supercritical fluid for initial pressure supplied through the integrated supply/discharge port. The substrate drying chamber according to claim 1, wherein the substrate is moved along and gradually diffuses into a processing area in which the substrate is disposed.
The method of claim 1,

A substrate drying chamber, characterized in that it further comprises a substrate support unit having one end coupled to the upper surface of the substrate arrangement plate and the other end coupled to the substrate, supporting the substrate and separating the substrate from the upper surface of the substrate arrangement plate .
The method of claim 15,

The second spaced space existing between the upper surface of the substrate arrangement plate and the substrate by the substrate support part includes a supercritical fluid for initial pressurization and the upper supply port supplied through the integrated supply/discharge port on the lower surface of the substrate. The substrate drying chamber, characterized in that to shorten the time of the drying process by exposure to the drying supercritical fluid supplied through.