Buffer tank and supply block

Abstract

To provide a buffer tank and a supply block that increase the pressure of the gas supplied into the chamber, and prevent or suppress the supply of impurities into the chamber. [Solution] A buffer tank 1110 for supplying gas to the inside of a chamber 100 for processing substrates, comprising an internal space 1112 that can communicate with the inside of the chamber and can contain gas, and a filter 1115 disposed in the internal space; and a supply block 1100 for supplying gas to the inside of a chamber for processing substrates, comprising a buffer tank comprising an internal space that can contain gas and a filter disposed in the internal space, and a gas block located on one side of the buffer tank, the gas block comprising a first flow path that can communicate with the internal space of the buffer tank and a second flow path that can communicate with the inside of the chamber and can communicate with the first flow path.

Description

Technical Field

[0001] The present invention relates to a buffer tank and a supply block, and more particularly to a buffer tank and a supply block capable of increasing the pressure of a gas supplied to a chamber.

Background Art

[0002] A substrate processing apparatus for depositing a thin film on a substrate includes a chamber, a support table disposed inside the chamber so as to support the substrate, and an injection unit disposed inside the chamber and injecting a gas toward the support table.

[0003] The injection unit is connected to a transfer pipe disposed outside the chamber, and the transfer pipe is connected to a storage unit in which a gas for a substrate processing step is stored. Therefore, after the gas in the storage unit flows into the injection unit through the transfer pipe, it is injected into the chamber through the injection unit.

[0004] On the other hand, the storage unit is positioned at a distance far from the chamber, and thus, the extension length of the transfer pipe is long. Therefore, when the gas in the storage unit passes through the transfer pipe and is injected from the injection unit, there is a problem that the injection pressure of the gas is low.

[0005] In the case of atomic layer deposition, in order to purge unreacted gas or reaction by-products after injection of a source gas or after injection of a reactant gas, a purge gas is injected into the chamber. However, since the purge gas discharged from the storage unit at a far distance passes through the transfer pipe and is then injected from the injection unit, the injection pressure of the purge gas is low. Therefore, there is a problem that the purge efficiency by the purge gas is reduced.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

[0007] The present invention provides a buffer tank capable of increasing the pressure of gas supplied inside a chamber, a supply block equipped with the buffer tank, and a gas supply device.

[0008] The present invention provides a buffer tank capable of preventing or suppressing the supply of impurities into the chamber, a supply block equipped with the buffer tank, and a gas supply device. [Means for solving the problem]

[0009] Embodiments of the present invention may include a buffer tank for supplying gas to the inside of a chamber for processing substrates, comprising an internal space that is in communication with the inside of the chamber and capable of containing gas, and a filter disposed in the internal space.

[0010] The buffer tank comprises a first body having a first space inside which gas can be contained, and a second body having a second space which is smaller in volume than the first space, is also capable of containing gas, and communicates with the first space, and is disposed in the first space, wherein the internal space of the buffer tank comprises the first space and the second space, the second space communicates with the inside of the chamber, and a heater may be disposed in the first body so as to be located in the first space.

[0011] The buffer tank may include a valve disposed between the second space and the chamber.

[0012] Embodiments of the present invention may be a supply block for supplying gas to the inside of a chamber for processing substrates, comprising: a buffer tank having an internal space capable of containing gas and a filter disposed in the internal space; and a gas block located on one side of the buffer tank, wherein the gas block comprises a first flow path that can communicate with the internal space of the buffer tank and a second flow path that can communicate with the inside of the chamber and can communicate with the first flow path.

[0013] In the supply block, the internal space of the buffer tank comprises a first space capable of containing gas and a second space having a smaller volume than the first space and defined from the first space, the filter is disposed in the second space, the second space communicates with the first space and may be equipped with a valve connected to the gas block to control communication between the first flow path and the second flow path.

[0014] The supply block may include a heater disposed in the buffer tank so as to be located in the first space. [Effects of the Invention]

[0015] According to an embodiment of the present invention, the gas from the gas supply unit can be retained inside the buffer tank for a predetermined period of time, thereby increasing the pressure inside the buffer tank. Consequently, the pressure of the gas discharged from the buffer tank can be increased, and this increases the injection pressure of the gas injected into the chamber connected to the buffer tank.

[0016] In this case, if the gas injected into the chamber is a purge gas, the purging efficiency using the purge gas can be increased. Furthermore, if the gas injected into the chamber is a gas that serves as a raw material for thin film deposition, the amount of gas that reaches the substrate can be increased, thereby increasing the thin film deposition efficiency.

[0017] By providing a filter inside the buffer tank through which the gas passes, it is possible to prevent or suppress impurities from mixing into the gas injected into the chamber. Therefore, it is possible to prevent contamination of the substrate or thin film by impurities.

Brief Description of the Drawings

[0018] [Figure 1] FIG. 1 is a diagram showing a substrate processing apparatus including a gas supply device according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a diagram showing a substrate processing apparatus including a gas supply device according to a second embodiment of the present invention. [Figure 3] FIG. 3 is a diagram for explaining the gas flow due to the operation of the valve of the gas supply device according to the second embodiment of the present invention. [Figure 4] FIG. 4 is a diagram for explaining the gas flow due to the operation of the valve of the gas supply device according to the second embodiment of the present invention. [Figure 5] FIG. 5 is a diagram showing a gas supply device according to a third embodiment of the present invention. [Figure 6] FIG. 6 is a diagram showing a gas supply device according to a fourth embodiment of the present invention.

Modes for Carrying Out the Invention

[0019] Hereinafter, embodiments of the present invention will be described in more detail based on the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and can be embodied in various different forms. These embodiments are merely provided to make the disclosure of the present invention complete and to fully inform those with ordinary knowledge of the scope of the invention. The drawings may be exaggerated for the purpose of explaining the embodiments of the present invention, and in the drawings, the same reference numerals indicate the same components.

[0020] FIG. 1 is a diagram showing a substrate processing apparatus including a gas supply device according to a first embodiment of the present invention.

[0021] Referring to FIG. 1, the substrate processing apparatus may include a chamber 100 having an internal space capable of processing a substrate S, a support table 200 for supporting the substrate S loaded into the chamber 100, an injection unit 400 disposed in the chamber 100 to face the support table 200 for injecting gas, and a gas supply device 1000 disposed outside the chamber 100 for supplying gas to the injection unit 400 so that the pressure of the gas injected from the injection unit 400 increases.

[0022] Further, the substrate processing apparatus may include a gas supply unit 500 for storing gas for injection into the chamber 100 and connected to the gas supply device 1000, a connection pipe 600 for connecting the gas supply unit 500 and the gas supply device 1000, an RF power supply unit 700 for supplying power to the injection unit 400 to generate plasma in the chamber 100, a drive unit 300 for causing at least one of the lifting operation and the rotation operation of the support table 200, and an exhaust unit 800 connected to the chamber 100 for exhausting at least one of the gas and by-products inside the chamber 100.

[0023] The chamber 100 has an internal space capable of processing the substrate S and hermetically holds the internal space. Such a chamber 100 may be provided, for example, with a body 110 having an internal space and a lid 120 covering the upper opening of the body 110.

[0024] The support table 200 is disposed inside the chamber 100 to face the injection unit 400 and supports the substrate S loaded into the chamber 100. The support table 200 may be made larger than the substrate S and may be provided in a shape corresponding to the substrate S, for example, a square shape. And the support table 200 may be grounded. Further, a heater 210 may be provided inside the support table 200. Therefore, when the heater 210 is operated, the substrate S placed on the support table 200 and the inside of the chamber 100 can be heated.

[0025] The injection unit 400 is positioned inside the chamber 100 so as to face the support base 200, and injects gas toward the support base 200. At this time, the injection unit 400 receives gas from a gas supply device 1000, which will be described later, and injects it into the chamber 100.

[0026] The injection unit 400 may be, for example, a showerhead-shaped unit having a plurality of injection holes 420. That is, the injection unit 400 may have an injection body 410 that extends in the extending direction of the support base 200 and has an internal space 430 capable of accommodating gas, and a plurality of injection holes 420 provided at the lower part of the injection body 410 so as to face the support base 200 and spaced apart in the extending direction of the support base 200. Alternatively, the injection unit 400 may have a passage inside that communicates with the internal space 430 of the injection body 410 and a supply pipe 440 that connects the gas supply device 1000 and the injection body 410. Each of the plurality of injection holes 420 is provided at the lower part of the injection body 410 so as to communicate with the internal space 430 below the internal space 430. Therefore, the gas that flows into the internal space 430 of the injection body 410 after passing through the supply pipe 440 is injected into the chamber 100 after passing through the plurality of injection holes 420.

[0027] The injection unit 400 is not limited in any way to the configuration or shape described above, and may be provided in any configuration or shape as long as it is capable of injecting gas into the chamber 100 or toward the support base 200.

[0028] The gas supply unit 500 is connected to the gas supply device 1000 and supplies or provides gas to the gas supply device 1000. When multiple types of gases are injected into the chamber 100 for substrate processing, the gas supply unit 500 may be provided in multiple units. To give a more specific example, if the substrate processing apparatus is an apparatus that deposits a thin film on a substrate S by atomic layer deposition (ALD), the gas supply unit 500 may include a first gas supply unit 500a that provides source gas, a second gas supply unit 500b that provides reactant gas, and a third gas supply unit 500c that provides purge gas.

[0029] Furthermore, each of the first to third gas supply sections 500a, 500b, and 500c may include a gas storage section 510a, 510b, and 510c, a transport section 520a, 520b, and 520c connecting the gas storage sections 510a, 510b, and 510c to the gas supply device 1000, and valves 530a, 530b, and 530c disposed in the transport section 520a, 520b, and 520c to control communication between the gas storage sections 510a, 510b, and 510c to the gas supply device 1000. In this case, the first gas storage section 510a may store source gas, the second gas storage section 510b may store reactant gas, and the third gas storage section 510c may store purge gas.

[0030] In the above description, the gas supply unit 500 was described as comprising three gas supply units 500a, 500b, and 500c. However, the number of gas supply units may be less than three or more than three. Furthermore, the gas supplied from the gas supply unit is not limited to the source gas, reactant gas, and purge gas used for atomic layer deposition, but can be any variety of gases injected into the chamber 100.

[0031] The gas supply device 1000 supplies gas to the injection unit 400 in such a way that the pressure of gas injected from the injection unit 400 increases. In other words, the gas supply device 1000 ensures that the injection pressure of gas injected from the injection unit 400 into the chamber 100 increases compared to when gas from the gas supply unit 500 is supplied to the injection unit 400 immediately or directly.

[0032] Such a gas supply device 1000 is a means of supplying gas to the injection unit 400 and may be disposed outside the chamber 100. More specifically, the gas supply device 1000 may be attached to the top of the chamber cover 1120, as shown in Figure 1. Needless to say, the location of the gas supply device 1000 is not limited to the top of the chamber 100, and it may be disposed at any location outside the chamber 100 as long as it can be connected to the injection unit 400.

[0033] The gas supply device 1000 may include a supply block 1100 having a buffer tank 1110 with an internal space for temporarily containing gas from a gas supply unit 500 so as to increase the pressure of the gas that moves to or is discharged to the injection unit 400, and a base 1200 disposed on top of the chamber 100 so as to be able to fasten and detach the supply block 1100.

[0034] The supply block 1100 may include a buffer tank 1110 having an internal space 1112 capable of containing gas and equipped with a filter 1115 capable of filtering out impurities. The supply block 1100 may further include a heater 1120 disposed inside the buffer tank 1110 to heat the gas. The supply block 1100 may also include a pressure measuring unit (not shown) for measuring the pressure inside the buffer tank 1110, and the pressure measuring unit may be disposed, for example, on the heater 1120.

[0035] The buffer tank 1110 temporarily stores the gas supplied from the gas supply unit 500 and is a means for supplying high-pressure gas to the inside of the chamber 100 or to the injection unit 400. Such a buffer tank 1110 has an internal space 1112, which comprises a first space 1112a and a second space 1112b that is defined by the first space 1112a. In this case, the volume of the first space 1112a may be larger than that of the second space 1112b, and a filter 1115 may be disposed in the second space 1112b.

[0036] More specifically, the buffer tank 1110 may include a first body 1111a having a first space 1112a inside which gas can be contained, a second body 1111b having a second space 1112b inside which gas can be contained and disposed in the first space 1112a of the first body 1111a, a filter 1115 disposed in the second space 1112b of the second body 1111b, a discharge pipe 1116 with one end connected to the second body 1111b and the other end connected to the injection unit 400, and a valve (hereinafter referred to as buffer valve 1117) disposed in the discharge pipe 1116 to control communication with the injection unit 400.

[0037] The first body 1111a may be a means that forms the outermost wall of the buffer tank 1110. Such a first body 1111a has an internal space capable of containing gas, i.e., a first space 1112a. In this case, the volume of the first space 1112a may be set to be larger than that of the second space 1112b, as described above.

[0038] The first body 1111a is provided with a first inlet 1113a that communicates with the connecting pipe 600 and the first space 1112a. In this case, the first inlet 1113a may be provided so as to be located outside the second body 1111b. In other words, the second body 1111b may be disposed in the first space 1112a so as to be located between the first inlet 1113a and the discharge pipe 1116. Therefore, the first inlet 1113a is located outside the second body 1111b, without overlapping with it.

[0039] The second body 1111b has an internal space capable of containing gas, i.e., a second space 1112b. This second body 1111b is disposed inside the first body 1111a. Here, the fact that the second body 1111b is disposed inside the first body 1111a may mean that the second body 1111b is disposed so as to be contained within the first space 1112a of the first body 1111a. In this case, the volume of the second space 1112b may be set to be smaller than that of the first space 1112a.

[0040] The second body 1111b is provided with a second inlet 1113b, which is a passage through which gas flowing into the first space 1112a flows into the second space 1112b, and an outlet 1114, which is a passage through which the gas in the second space 1112b is discharged to the discharge pipe 1116. For this reason, the second space 1112b can be described as the space between the second inlet 1113b and the outlet 1114. The gas that flows into the first space 1112a of the first body 1111a via the first inlet 1113a may then flow into the second space 1112b via the second inlet 1113b of the second body 1111b, and then be discharged to the outside via the outlet 1114 and the discharge pipe 1116.

[0041] The discharge pipe 1116 is a means for discharging the gas inside the buffer tank 1110 to the outside, i.e., to the injection unit 400. More specifically, the discharge pipe 1116 supplies the gas that has flowed into the second space 1112b of the second body 1111b to the injection unit 400. For this purpose, the discharge pipe 1116 is provided such that one end is connected to the outlet 1114 of the second body 1111b and the other end is connected to the supply pipe 440 of the injection unit 400. In this case, the discharge pipe 1116 may be provided so as to partially penetrate the first body 1111a, as shown in Figure 1. That is, it may be provided or arranged so as to penetrate a part of the region of the first body 1111a between the second body 1111b and the injection unit 400.

[0042] The buffer valve 1117 is positioned in the discharge pipe 1116 to control communication between the second space 1112b and the injection section 400. That is, the buffer valve 1117 may be positioned in the discharge pipe 1116 so as to be located on the extension path of the discharge pipe 1116. In this case, the buffer valve 1117 may be operated by means of an externally applied signal or force. Alternatively, the buffer valve 1117 may be configured to operate based on the pressure inside the buffer tank measured in the pressure measuring section.

[0043] The filter 1115 filters out impurities such as solid phase particles and powders that are mixed in the gas, located inside the second body 1111b, i.e., in the second space 1112b. Here, the filter 1115 may be a means that has multiple openings smaller in size than the particles to be filtered out. To give another example, the filter 1115 may be an electrostatic filter that uses static electricity to adsorb fine particles mixed in the gas. Needless to say, the filter 1115 is not limited to the examples described above, and a wide variety of means can be used as long as they can filter out impurities mixed in the gas.

[0044] The heater 1120 is a means provided to prevent the liquefaction of gas flowing into the buffer tank 1110, and heats the gas in the internal space of the buffer tank 1110. Such a heater 1120 is arranged to be located inside the first body 1111a. That is, the heater 1120 may be arranged in the first body 1111a so as to be located in the first space 1112a. In this case, the heater 1120 is arranged in the first space 1112a so as to be located outside the second body 1111b or the second space 1112b.

[0045] The heater 1120 may be, for example, a means comprising a metal heating element that generates heat due to the resistance caused by the applied current. In such a case, a power supply unit 1130 that applies current may be connected to the heater 1120, and the power supply unit 1130 may be located outside the buffer tank 1110.

[0046] The base 1200 supports the supply block 1100 and is a means for mounting the supply block 1100 to the chamber 100. In other words, the base 1200 plays a role in allowing the multiple components of the supply block 1100 to be easily mounted on top of the chamber 100.

[0047] For example, when the supply block 1100 includes one buffer tank 1110, the base 1200 is provided so that the buffer tank 1110 can be fastened and detached. In this case, since the buffer tank 1110 is located on top of the base 1200, the base 1200 is provided with a flow path 1210 that can deliver the gas discharged from the buffer tank 1110 to the inside of the chamber 100 or to the injection unit 400. More specifically, the base 1200 is provided with a flow path 1210 that is connected to the discharge pipe 1116 of the buffer tank 1110. As a result, the gas discharged from the discharge pipe 1116 of the buffer tank 1110 passes through the flow path 1210 of the base 1200 and is then injected into the inside of the chamber 100 via the injection unit 400.

[0048] Furthermore, the supply block 1100 may comprise multiple components. For example, the supply block 1100 may comprise multiple buffer tanks 1110, or it may further comprise components different from the buffer tanks 1110. In this case, the buffer tanks 1110 and the other components may, for example, be means provided with a space through which gas can be contained or passed. For this reason, the base 1200 may be provided with multiple flow paths 1210 so that multiple buffer tanks 1110 can be fastened together, or additional components can be fastened together in addition to the buffer tanks 1110, as needed. In this case, the multiple flow paths 1210 may be provided at different positions from each other.

[0049] Thus, by providing the base 1200 with multiple flow paths 1210 located at different positions from each other, multiple buffer tanks 1110 can be attached to the base 1200, or other components can be attached or assembled in addition to the buffer tanks 1110, as needed. In other words, it is easy to further assemble multiple buffer tanks 1110 or other components in addition to the buffer tanks 1110 into the chamber 100, as needed. That is, to control the gas supplied into the chamber 100, for example, to control the type of gas, flow rate, pressure, etc., multiple buffer tanks 1110 can be attached, or other components can be attached or assembled in addition to the buffer tanks 1110, as needed.

[0050] Furthermore, separate fastening members may be used to fasten or separate the supply block 1100 and the base 1200 from each other. For example, when the supply block 1100 comprises a buffer tank 1110, fastening members may be provided that can fasten or separate the buffer tank 1110 and the base 1200 from each other. For example, the fastening member may comprise a fastening body that is partially fitted into the first body 1111a of the buffer tank 1110 and the base 1200, and a fixing body that secures the fastening body to the first body 1111a from the outside of the first body 1111a. In this case, the fastening body may be a bolt with threads formed on its outer circumference, and the fixing body may be a nut with threads formed on its inner circumference. Furthermore, fastening holes may be provided in both the buffer tank 1110 and the base 1200 into which the fastening body can be fitted or passed through. Such fastening members and fastening holes allow the buffer tank 1110 to be fastened or coupled to the base 1200 and to be detached from the base 1200.

[0051] As described above, the supply block 1100 may include a plurality of buffer tanks 1110, or it may include other components in addition to the buffer tanks 1110. In this case, each of the plurality of buffer tanks 1110 or the buffer tanks 1110 plus other components may be fastened to the base 1200 using fastening members. The base 1200 may be provided with a plurality of fastening holes into which each of the plurality of fastening members can be fitted, and the plurality of fastening holes may be provided at different positions from each other.

[0052] Thus, by providing the base 1200 with multiple flow paths 1210 and multiple fastening holes located at different positions from each other, multiple buffer tanks 1110 can be attached to the base 1200 as needed, or other components can be attached or assembled in addition to the buffer tanks 1110. In other words, as described above, in order to control the gas supplied to the inside of the chamber 100, for example, to control the type of gas, flow rate, pressure, etc., multiple buffer tanks 1110 can be attached as needed, or other components can be attached or assembled in addition to the buffer tanks 1110.

[0053] Thus, the supply block 1100 of the gas supply device 1000 according to the first embodiment includes a buffer tank 1110 capable of temporarily storing gas from the gas supply unit 500. In other words, the gas supply device 1000 includes a buffer tank 1110 connected between the gas supply unit 500 and the injection unit 400.

[0054] Such a buffer tank 1110 prevents the gas supplied from or discharged from the gas supply unit 500 from moving directly to the injection unit 400, but instead allows it to move to the injection unit 400 under high pressure. More specifically, with the buffer valve 1117 closed, the gas from the gas supply unit 500 is supplied to the connecting pipe 600. As a result, the gas that has passed through the connecting pipe 600 flows into the internal space 1112 of the buffer tank 1110. That is, the gas that has passed through the connecting pipe 600 flows into the first space 1112a of the first body 1111a via the first inlet 1113a, and then the gas flows into the second space 1112b of the second body 1111b. Then, if gas continues to be supplied to the first space 1112a with the buffer valve 1117 closed, the pressure in the internal space 1112 of the buffer tank 1110, that is, the pressure in the first space 1112a and the second space 1112b which is in communication with the first space 1112a, will increase.

[0055] Subsequently, when the pressure in the internal space 1112 of the buffer tank 1110 reaches a predetermined or preset pressure, the supply of gas from the gas supply unit 500 is interrupted and the buffer valve 1117 is opened.

[0056] In this case, the pressure in the internal space 1112 of the buffer tank 1110 can be measured, for example, using a pressure adjustment unit installed in the heater 1120. The buffer valve 1117 may then be operated to open when the pressure measured in the pressure measuring unit reaches a preset pressure.

[0057] When the buffer valve 1117 is opened, the gas in the internal space 1112 of the buffer tank 1110 passes through the discharge pipe 1116 and the flow path 1210 of the base 1200 and is supplied to the injection unit 400, and then injected into the chamber 100 via the injection unit 400. That is, the gas in the second body 1111b or the second space 1112b of the buffer tank 1110 is discharged to the outside of the buffer tank 1110 via the discharge pipe 1116, then supplied to the injection unit 400 via the flow path 1210 provided in the base 1200, and then injected through the injection hole 420 of the injection unit 400. At this time, the pressure in the internal space 1112 of the buffer tank 1110 is high, so the pressure at which the gas in the internal space 1112 of the buffer tank 1110 is discharged via the discharge pipe 1116 is high, and therefore the injection pressure at which the gas is injected into the chamber via the injection unit 400 is high.

[0058] Therefore, compared to supplying the gas from the gas supply unit 500 directly to the injection unit 400, when the gas is temporarily stored in the buffer tank 1110 before being supplied to the injection unit 400, as in the embodiment, the gas can be injected into the chamber 100 at a higher pressure.

[0059] Furthermore, if the gas from the gas supply unit 500 is, for example, a purge gas, the purge gas can be injected at a high injection pressure, which has the effect of improving purging efficiency. This is because, when the amount of purge gas injected is the same, as in the embodiment, when the injection pressure is high, the amount of by-products or impurities purged into the chamber increases relatively.

[0060] To give another example, if the gas from the gas supply unit 500 is a gas for thin film deposition, such as a source gas or reactant gas, the source gas or reactant gas can be injected at a high injection pressure through the injection unit 400, which has the effect of improving the deposition rate. In particular, when a thin film is deposited in a trench provided in the substrate S, the injection pressure of the source gas or reactant gas is high, and the gas can easily reach the inside of the trench. Therefore, when the amount of source gas or reactant gas injected is the same, a higher injection pressure results in a relative increase in the amount of gas that reaches the trench, thus increasing the deposition rate.

[0061] Furthermore, in this embodiment, the heater 1120 may be used to heat the gas in the internal space 1112 of the buffer tank 1110. That is, the gas in the first space 1112a and the second space 1112b may be heated. This prevents the gas temperature from dropping and liquefying while it is contained or stored in the internal space 1112 of the buffer tank 1110 for a predetermined period of time.

[0062] Furthermore, a filter 1115 is provided in the internal space 1112 of the buffer tank 1110. That is, the filter 1115 is positioned in the second space 1112b of the second body 1111b. A discharge pipe 1116 is provided to connect to the second space 1112b of the second body 1111b, and a buffer valve 1117 is provided in the discharge pipe 1116. As a result, the gas in the internal space 1112 of the buffer tank 1110 flows into the second space 1112b of the second body 1111b and is then discharged through the discharge pipe 1116. In other words, the gas in the buffer tank 1110 is discharged through the second space 1112b and then through the discharge pipe 1116. Therefore, the gas flows towards the discharge pipe 1116 while passing through the filter 1115. In this way, when the gas passes through the filter 1115, any impurities mixed in the gas cannot pass through the filter 1115. In other words, impurities are filtered out by the filter 1115. As a result, the gas from which impurities have been filtered out or removed is supplied to the injection unit 400 via the discharge pipe 1116. Therefore, it is possible to prevent or suppress the supply of impurities to the injection unit 400, which has the effect of improving the processing quality of the substrate S, for example, the quality of the thin film.

[0063] Figure 2 shows a substrate processing apparatus equipped with a gas supply device according to a second embodiment of the present invention. Figures 3 and 4 are diagrams illustrating the gas flow due to the operation of a valve in the gas supply device according to a second embodiment of the present invention.

[0064] In the first embodiment described above, the supply block 1100 is provided with a buffer tank 1110, the buffer tank 1110 is directly connected to the injection unit 400, and a buffer valve 1117 is provided in the discharge pipe 1116. However, the present invention is not limited thereto, and as in the second embodiment shown in Figures 2 to 4, the supply block 1100 may further be provided with a buffer tank 1110 and a gas block 1150 connecting the buffer tank 1110 and the injection unit 400.

[0065] Hereinafter, a gas supply device 1000 according to a second embodiment of the present invention will be described with reference to Figures 2 to 4. In this case, content that overlaps with the first embodiment will be omitted or described in a simplified manner.

[0066] Referring to Figure 2, the supply block 1100 of the gas supply device 1000 according to the second embodiment may include a buffer tank 1110 having an internal space 1112 capable of temporarily containing gas and equipped with a filter 1115 capable of filtering out impurities, a gas block 1150 having a first flow path 1152a connected to the buffer tank 1110 and a second flow path 1152b connected to a flow path 1210 of the base 1200, and a valve 1160 disposed in the gas block 1150 to close or open the first and second flow paths 1152a and 1152b, respectively. The supply block 1100 may further include a heater 1120 disposed in the internal space 1112 of the buffer tank 1110 to heat the gas. The supply block 1100 may also include a pressure measuring unit (not shown) for measuring the pressure inside the buffer tank 1110, and the pressure measuring unit may be disposed, for example, in the heater 1120.

[0067] The buffer tank 1110 has substantially the same configuration or structure as the first embodiment described above. However, in the buffer tank 1110 according to the second embodiment, the discharge pipe 1116 is not connected to the flow path 1210 of the base 1200, but is connected to the first flow path 1152a of the gas block 1150, which will be described later.

[0068] The gas block 1150 comprises a fuselage 1151, a first flow path 1152a provided within the fuselage 1151 to connect the buffer tank 1110 and the valve 1160, and a second flow path 1152b provided within the fuselage 1151 to connect the valve 1160 and the injection unit 400.

[0069] The body 1151 may, for example, have the shape of a hexahedron with a quadrilateral cross-section. Needless to say, the body 1151 is not limited in any way to the examples described above, and can be changed to a wide variety of shapes that allow for the provision of first and second flow channels 1152a and 1152b inside.

[0070] The first flow path 1152a is provided inside the body 1151 such that one end is connected to the discharge pipe 1116 of the buffer tank 1110 and the other end is connected to the valve 1160. In this case, if the buffer tank 1110 is located on the side of the gas block 1150 and the valve 1160 is located on the top of the gas block 1150, the first flow path 1152a may have a shape that extends upward from the side of the body 110. In such a case, the first flow path 1152a may be provided such that one end is exposed on the side of the body 1151 and the other end is exposed on the top surface of the body 1151.

[0071] The second flow path 1152b is provided inside the body 1151 such that one end is connected to the valve 1160 and the other end is connected to the flow path 1210 of the base 1200. In this case, if the valve 1160 is located on the upper part of the gas block 1150 and the base 1200 is located on the lower part of the gas block 1150, the second flow path 1152b may have a shape that extends from the upper part to the lower part of the body 1151. In such a case, the second flow path 1152b may be provided such that one end is exposed on the upper surface of the body 1151 and the other end is exposed on the lower surface of the body 1151.

[0072] Valve 1160 controls communication between the first passage 1152a and the second passage 1152b of the gas block 1150. Valve 1160 may be configured to operate based on the pressure inside the buffer tank 1110 measured in the pressure measuring unit. Such a valve 1160 may be, for example, a diaphragm valve.

[0073] Although not shown in the diagram, the valve 1160, which is a diaphragm valve, can be described as follows. The valve 1160 may include, for example, a main body having first and second passages that can communicate with the first and second flow paths 1152a and 1152b of the gas block 1150, respectively; an adjustment unit disposed inside the main body so as to be movable forward toward the gas block 1150 or backward toward the opposite side of the gas block 1150; a weir disposed inside the main body so as to be positioned opposite the adjustment unit; and a diaphragm positioned between the adjustment unit and the weir and connected to the lower part of the adjustment unit.

[0074] The main body may comprise a first body and a second body that are separable and fastened to each other. A diaphragm may be disposed between the first body and the second body. In this case, the peripheral edge of the diaphragm may be positioned between the lower part of the first body and the upper part of the second body, so that the first body, the diaphragm, and the second body are connected to each other. For example, a separate fastening member may be disposed to penetrate the lower part of the first body, the diaphragm, and the second body, thereby connecting the first body, the diaphragm, and the second body to each other. In this case, the peripheral edge of the diaphragm is fixed to the first body and the second body, while the rest is exposed to the internal space of the first body and the second body. Thus, the internal space of the main body can be divided by the diaphragm into an upper space and a lower space.

[0075] The diaphragm is an expandable and retractable means. As described above, the peripheral edge of the diaphragm is fixed between the lower part of the first body and the upper part of the second body, while the remainder is exposed to the internal space of the main body. At this time, the upper surface of the diaphragm exposed to the internal space of the main body is coupled or connected to the lower part of the adjustment unit.

[0076] Therefore, the shape of the diaphragm is deformed by the operation of the adjustment unit, and this deformation causes the diaphragm and the weir to move closer to and further apart from each other. At this time, the adjustment unit may be configured to operate based on the pressure inside the buffer tank 1110 measured in the pressure measuring unit.

[0077] In other words, when the adjustment unit moves forward in the direction in which the weir is positioned, the shape of the diaphragm connected to the lower part of the adjustment unit is deformed so that it becomes convex toward the weir. When the lower surface of the diaphragm comes into contact with the weir at this time, the first passage and the second passage of the valve 1160 do not communicate. That is, the first passage and the second passage are blocked by the diaphragm or the weir. As a result, the first passage 1152a and the second passage 1152b of the gas block 1150 do not communicate. In such a case, the gas from the gas supply unit 500 is contained in the internal space 1112 of the buffer tank 1110, the first passage 1152a of the gas block 1150, and the first passage of the valve 1160. That is, the gas discharged from the buffer tank 1110 flows into the first passage, which is the inside of the valve 1160, via the first passage 1152a of the gas block 1150, as shown in Figure 3. At this time, the gas does not flow into the second passage, and therefore, as shown in Figure 3, no gas is discharged outside the gas block 1150. If gas continues to be supplied from the gas supply unit 500 to the buffer tank 1110, the pressure in the internal space 1112 of the buffer tank 1110, the first flow path 1152a of the gas block 1150, and the first passage of the valve 1160 increases.

[0078] Conversely, if the adjustment unit moves backward on the opposite side of the weir, the shape of the diaphragm is deformed so that it becomes convex on the opposite side of the weir. At this time, when the lower surface of the diaphragm separates from the weir and moves away from it, the first passage and the second passage of the valve 1160 come into communication. That is, the first passage and the second passage come into communication with each other through the separation space between the diaphragm and the weir. As a result, the first passage 1152a and the second passage 1152b of the gas block 1150 come into communication. Consequently, the gas that has passed through the first passage 1152a of the gas block 1150 flows through the first and second passages of the valve 1160 and flows back into the second passage 1152b of the gas block 1150, as shown in Figure 4. After this, the gas flows into the injection unit 400 via the passage 1210 of the base 1200, which is connected to the second passage 1152b.

[0079] At this time, the pressure in the internal space 1112 of the buffer tank 1110, the first flow path 1152a of the gas block 1150, and the first passage of the valve 1160 is high, so the pressure at which the gas flows into the second passage is high. As a result, the pressure at which the gas is supplied to the injection unit 400 after passing through the second passage, the second flow path 1152b of the gas block 1150, and the flow path 1210 of the base 1200 is high, so the injection pressure of the gas injected through the injection unit 400 is high. In other words, compared to when the gas from the gas supply unit 500 is supplied directly to the injection unit 400, when the gas is temporarily stored in the buffer tank 1110 before being supplied to the injection unit 400, as in the second embodiment, the gas can be injected into the chamber 100 at a higher pressure.

[0080] Figure 5 shows a gas supply device according to a third embodiment of the present invention.

[0081] The buffer tank 1110 of the gas supply device according to the third embodiment may further include a back pressure prevention unit 1117 disposed in the first space 1112a.

[0082] The buffer tank 1110 according to the third embodiment will be described below with reference to Figure 5. In this description, any content that overlaps with the first embodiment will be omitted or explained in a simplified manner.

[0083] Referring to Figure 5, the buffer tank 1110 according to the third embodiment comprises a first body 1111a having a first space 1112a inside which gas can be contained, a second body 1111b having a second space 1112b inside which gas can be contained and disposed in the first space 1112a of the first body 1111a, a filter 1115 disposed in the second space 1112b of the second body 1111b, a discharge pipe 1116 having one end connected to the second body 1111b and the other end connected to the injection unit 400, a buffer valve 1117 disposed in the discharge pipe 1116 to control communication with the injection unit 400, and a back pressure prevention unit 1117 disposed in the first space 1112a.

[0084] Then, as in the first embodiment, the heater 1120 is disposed in the first space 1112a of the first body 1111a. The back pressure prevention unit 1117 may be attached to the outer circumferential surface of the heater 1120 so as to be positioned in the first space 1112a, as shown in Figure 5. In other words, the back pressure prevention unit 1117 may be disposed on the outer circumferential surface of the heater 1120 so as to enclose the heater 1120 in the circumferential or diametrical direction. In this case, the back pressure prevention unit 1117 is disposed on the heater 1120 so as to be positioned behind the connecting pipe 600. More specifically, it is attached to the outer circumferential surface of the heater 1120 so as to be positioned behind the connecting pipe 600 in the first space, with reference to the direction in which the gas supplied from the connecting pipe 600 flows to the outlet 1114. The fact that the reverse pressure prevention unit 1117 is located in the first space 1112a may mean that it is located outside the second space 1112b.

[0085] As described above, the reverse pressure prevention unit 1117 is located in the first space 1112a and behind the connecting pipe 600. Therefore, the first space 1112a of the first body 1111a can be described as comprising a space located on one side of the reverse pressure prevention unit 1117 (hereinafter referred to as the space on one side A1) and a space located on the other side of the reverse pressure prevention unit 1117 (hereinafter referred to as the space on the other side A2). Thus, the reverse pressure prevention unit 1117 can be described as being located between the space on one side A1 and the space on the other side A2 of the first space 1112a.

[0086] The connecting pipe 600 is then connected to the first body 1111a so as to communicate with space A1 on one side. The position of the reverse pressure prevention unit 1117 is also adjusted so that the size of space A2 on the other side is larger than the size of space A1 on the one side.

[0087] As shown in Figure 5, the reverse pressure prevention section 1117 is provided with a shape in which its outer circumferential surface has a slope. That is, the reverse pressure prevention section 1117 is provided with a slope that gradually approaches the inner wall of the first body 1111a as it moves from one side, space A1, toward the other side, space A2. In other words, the reverse pressure prevention section 1117 may be provided with a shape in which its outer diameter gradually increases as it moves from one side, space A1, toward the other side, space A2. For this reason, the reverse pressure prevention section 1117 may be provided with a sloped outer circumferential surface.

[0088] Furthermore, the outer surface of the reverse pressure prevention unit 1117 is separated from the inner wall of the first body 1111a by a predetermined distance. As a result, gas that flows into one space A1 can move to the other space A2 through the space between the reverse pressure prevention unit 1117 and the inner wall of the first body 1111a.

[0089] Such a back pressure prevention unit 1117 can prevent the generation of back pressure of gas from one side of the first space 1112a to the other side of the space A2.

[0090] Figure 6 shows a gas supply device according to the fourth embodiment of the present invention.

[0091] The buffer tank 1110 of the gas supply device 1000 according to the fourth embodiment may include a cover 1118 that closes the opening of the buffer tank 1110, through which the heater 1120 passes, while providing a flow path P through which gas can pass.

[0092] The buffer tank 1110 according to the fourth embodiment will be described below with reference to Figure 6. In this description, any content that overlaps with the first embodiment will be omitted or explained in a simplified manner.

[0093] Referring to Figure 6, the buffer tank 1110 according to the fourth embodiment comprises a first body 1111a having a first space 1112a inside which gas can be contained, a cover 1118 having a flow path P inside which gas can pass while closing the opening of the first body 1111a, a second body 1111b having a second space 1112b inside which gas can be contained and disposed in the first space 1112a of the first body 1111a, a filter 1115 disposed in the second space 1112b of the second body 1111b, a discharge pipe 1116 having one end connected to the second body 1111b and the other end connected to the injection unit 400, and a buffer valve 1117 disposed in the discharge pipe 1116 to control communication with the injection unit 400.

[0094] The first body 1111a is provided with an opening through which the heater 1120 can pass. In this case, the opening may be positioned, for example, opposite the discharge pipe 1116.

[0095] The cover 1118 is a means for closing an opening provided in the first body 1111a. Such a cover 1118 may be arranged such that a portion is fitted into the opening in the first body 1111a and the remainder protrudes outside the first body 1111a. A heater 1120 may be connected to or attached to one side of the cover 1118 that is fitted into the opening in the first body 1111a and exposed to the first space 1112a.

[0096] A flow path P is provided inside the cover 1118 through which gas can move or pass. When the buffer tank 1110 is equipped with the cover 1118 in this way, the connecting pipe is arranged to connect to the cover 1118. That is, the connecting pipe 600 is arranged in the cover 1118 so as to communicate with the flow path P provided in the cover 1118. Therefore, one end of the flow path P communicates with the connecting pipe, and the other end communicates with the first space 1112a of the first body 1111a. Consequently, the gas supplied to the connecting pipe 600 is supplied to the first space 1112a of the first body 1111a via the flow path P provided in the cover 1118.

[0097] Thus, in the fourth embodiment, the opening of the first body 1111a is covered with a cover 1118 provided with a flow path, and the connecting pipe 600 is connected to the cover 1118. The cover 1118 is also arranged to be connected to the heater 1120. Therefore, by removing the cover 1118 from the first body 1111a, the heater 1120 and the connecting pipe 600 can be removed from the first body 1111a or the buffer tank 1110. Also, by attaching the cover 1118 to the first body, the heater 1120 can be arranged in the first space 1112a of the first body 1111a, and the connecting pipe 600 can be connected to the buffer tank 1110. Thus, by attaching or removing the cover 1118 from the first body 1111a, the heater 1120 and the connecting pipe 600 can be easily removed from or attached to the buffer tank 1110.

[0098] In the embodiments described above, the filter 1115 was described as being disposed inside the buffer tank 1110. However, the present invention is not limited thereto, and the filter 1115 may be disposed separately from the buffer tank 1110 and disposed outside the buffer tank 1110. The filter 1115 may also be positioned between the buffer tank 1110 and the base 1200, and the filter 1115 may be disposed to connect the buffer tank 1110 and the base 1200.

[0099] Thus, the filter is either installed inside the buffer tank 1110 or installed to connect the buffer tank 1110 and the base 1200. In other words, the filter 1115 according to this embodiment is installed in a position adjacent to the buffer tank 1110.

[0100] The operation of a substrate processing apparatus equipped with a gas supply device according to the first embodiment of the present invention will be described below with reference to Figure 1. In this case, a method of depositing a thin film on a substrate by atomic layer deposition will be used as an example.

[0101] First, the substrate S is placed on the support base 200. At this time, the heater 1120 provided on the support base 200 may be operated before placing the substrate S, or the heater 1120 may be operated after the substrate S has been placed, to heat the substrate S to the required process temperature.

[0102] Next, a thin film is deposited on the substrate S by atomic layer deposition. For this purpose, a source gas, purge gas, reactant gas, and purge gas are injected into the chamber 100 in this order using the injection unit 400. That is, "injection of source gas, injection of purge gas, injection of reactant gas, injection of purge gas" constitutes one process cycle, and this process cycle is repeated multiple times. Alternatively, RF power may be supplied to the injection unit 400 using the RF power supply unit 700 when the reactant gas is injected. This makes it possible to generate plasma inside the chamber 100 due to the ionization of the reactant gas.

[0103] The source gas injected into the chamber 100 is adsorbed onto the substrate S. The reactant gas is then ionized by the plasma, and the ionized reactant gas reacts with the source gas adsorbed on the substrate S, thereby forming a thin film on the substrate S due to the reaction between the source gas and the reactant gas. The above process cycle is repeated multiple times to form a thin film of the target thickness.

[0104] The following describes how gas is supplied to the injection unit 400. The method of supplying purge gas to the injection unit 400 will be used as an example.

[0105] To supply purge gas to the injection unit 400, the purge gas is supplied to the injection unit 400 using the third gas supply unit 500c. That is, the third valve 1160 is opened to discharge the purge gas from the third storage unit 510c to the third transport unit 520b. As a result, the source gas from the third storage unit 510c passes through the third transport unit 520b and the connecting pipe 600 before being supplied to the buffer tank 1110 of the gas supply device 1000. More specifically, the purge gas that has passed through the third transport unit 520b and the connecting pipe 600 flows into the internal space 1112 of the buffer tank 1110 via the first inlet 1113a of the buffer tank 1110. In other words, the purge gas flows into the first space 1112a of the first body 1111a through the first inlet 1113a provided in the first body 1111a.

[0106] At this time, the buffer valve 1117 of the buffer tank 1110 is closed. As a result, the purge gas that has flowed into the buffer tank 1110 remains in the internal space 1112 of the buffer tank 1110 without being discharged to the outside. Furthermore, if the purge gas is continuously supplied to the buffer tank 1110 using the third gas supply unit 500c, the pressure in the internal space 1112 of the closed buffer tank 1110 will gradually increase.

[0107] Furthermore, while the purge gas remains in the internal space 1112 of the buffer tank 1110, the purge gas may be heated by the operation of the heater 1120. In other words, the purge gas in the internal space 1112 may be heated by the operation of the heater 1120 so that its temperature does not fall below a predetermined temperature. This prevents the purge gas from liquefying even if it remains in the internal space 1112 of the buffer tank 1110 for a predetermined period of time.

[0108] When the pressure in the internal space 1112 of the buffer tank 1110 increases to a preset pressure, the supply of purge gas from the third gas supply unit 500c is interrupted and the buffer valve 1117 is opened. For this purpose, the buffer tank 1110 may be provided with means for measuring the pressure in its internal space. Needless to say, the present invention is not limited thereto, and a time may be set for the pressure in the internal space 1112 of the buffer tank 1110 to reach a target pressure, and gas may be supplied from the gas supply unit 500 to the buffer tank 1110 during the set time.

[0109] When the buffer valve 1117 is opened, the purge gas in the internal space of the buffer tank 1110 is discharged to the outside via the discharge pipe 1116. That is, the purge gas in the first space 1112a of the first body 1111a flows into the second space 1112b of the second body 1111b, and the purge gas in the second space 1112b is discharged via the discharge pipe 1116. At this time, the pressure in the internal space 1112 of the buffer tank 1110 is high, so the pressure at which the purge gas is discharged via the discharge pipe 1116 is high.

[0110] The purge gas that has passed through the discharge pipe 1116 is then supplied to the injection unit 400 via the flow path 1210 of the base 1200, which is connected to the discharge pipe 1116. After this, the purge gas is discharged into the chamber 100 through the injection holes 420 provided in the injection unit 400.

[0111] At this time, the pressure of the purge gas discharged from the discharge pipe 1116 of the buffer tank 1110 is high, so the pressure at which the purge gas discharged from the discharge pipe 1116 is supplied to the flow path 1210 of the base 1200 and the injection unit 400 is high, and as a result the injection pressure of the purge gas injected through the injection unit 400 is high. Therefore, the purging efficiency by injection of purge gas is improved. In other words, after the injection of source gas or reactant gas, purge gas is injected to purge unreacted gas, reaction byproducts, etc. inside the chamber 100, and at this time, the injection pressure of the purge gas increases, which improves the purging efficiency by purge gas. To put it another way, purging can be performed effectively using the same amount of purge gas.

[0112] A detailed explanation of how the source gas and reactant gas from the first and second gas supply units 500a and 500b are supplied to the injection unit 400 via the gas supply device 1000 will be omitted, but they are supplied to the injection unit 400 through the same process as the purge gas supply method described above. Therefore, the injection pressure of the source gas and reactant gas injected from the injection unit 400 can be increased. Consequently, the amount of source gas and reactant gas that reaches the substrate S increases, resulting in an improved deposition rate.

[0113] When the gas is discharged to the outside of the buffer tank 1110, it passes through the filter 1115 located inside the buffer tank 1110. At this time, impurities mixed in the gas are filtered or filtered out by the filter 1115. This prevents or suppresses the mixing of impurities into the gas injected into the chamber 100. This prevents contamination of the substrate or thin film by impurities. [Industrial applicability]

[0114] According to an embodiment of the present invention, the gas from the gas supply unit can be retained inside the buffer tank for a predetermined period of time, thereby increasing the pressure inside the buffer tank. Consequently, the pressure of the gas discharged from the buffer tank can be increased, and this increases the injection pressure of the gas injected into the chamber connected to the buffer tank.

Claims

1. A buffer tank that supplies gas inside a chamber for processing substrates, An internal space that can communicate with the inside of the chamber and can contain gas, A filter is installed in the aforementioned internal space, A buffer tank equipped with the following features.

2. The buffer tank is A first body having a first space inside which gas can be contained, A second body is disposed in the first space, having a smaller volume than the first space, capable of containing gas, and communicating with the first space. The internal space of the buffer tank comprises the first space and the second space, The second space is in communication with the inside of the chamber, The buffer tank according to claim 1, wherein a heater is provided in the first body so as to be located in the first space.

3. The buffer tank according to claim 1, further comprising a valve disposed between the second space and the chamber.

4. A supply block that supplies gas to the inside of a chamber for processing substrates, A buffer tank comprising an internal space capable of containing gas and a filter disposed in the internal space, The buffer tank comprises a gas block located on one side of the buffer tank, The aforementioned gas block is A first flow path that can communicate with the internal space of the buffer tank and a second flow path that can communicate with the inside of the chamber and can communicate with the first flow path, A supply block equipped with the following features.

5. The internal space of the buffer tank comprises a first space capable of containing gas and a second space having a smaller volume than the first space and defined from the first space. The filter is disposed in the second space, The second space is in communication with the first space, The supply block according to claim 4, further comprising a valve connected to the gas block to control communication between the first flow path and the second flow path.

6. The supply block according to claim 5, further comprising a heater disposed in the buffer tank so as to be located in the first space.

Images