The present disclosure relates to a substrate cooling member that cools a substrate such as, for example, a semiconductor wafer, a substrate processing apparatus including the substrate cooling member, and a substrate processing method using the substrate cooling member.
A substrate processing apparatus known in the related art includes a vacuum processing chamber that processes a substrate such as, for example, a semiconductor wafer, in a vacuum (decompressed) atmosphere and at a high temperature. In the substrate processing apparatus, it is required to cool a substrate processed in the vacuum processing chamber to a predetermined temperature and to carry the substrate out to the outside which is under an atmospheric pressure (e.g., a container that accommodates a plurality of substrates). Thus, the following process has been known.
That is, the substrate processed in vacuum processing chamber is carried into an intermediate conveyance chamber, which is maintained at a vacuum atmosphere so as to place substrates therein, by a conveyance apparatus provided in a conveyance chamber maintained at a vacuum atmosphere (hereinafter, referred to as a “vacuum conveyance chamber), and is placed on a cooling table disposed in the intermediate conveyance chamber. Here, the intermediate conveyance chamber is arranged between the vacuum conveyance chamber and another conveyance chamber maintained at the atmospheric pressure (hereinafter, referred to as an “atmospheric conveyance chamber”). The intermediate conveyance chamber is configured such that its atmosphere is capable of being isolated from or communicated with the conveyance chambers.
After the substrate processed in the vacuum processing chamber is carried into the intermediate conveyance chamber which is isolated from the atmospheric conveyance chamber to be maintained at the vacuum atmosphere, the intermediate conveyance chamber is also isolated from the vacuum conveyance chamber and a purge gas such as, for example, nitrogen gas, is introduced into the intermediate conveyance chamber to return the interior of the intermediate conveyance chamber to the atmospheric pressure, during which the substrate is cooled by a cooling plate. When the interior of the intermediate conveyance chamber becomes the atmospheric pressure and the substrate is also fully cooled, the intermediate conveyance chamber and the atmospheric conveyance chamber are communicated with each other while the isolation state between the intermediate conveyance chamber and the vacuum conveyance chamber is maintained, and the substrate is taken out from the intermediate conveyance chamber and carried into a substrate accommodating container by a conveyance apparatus provided in the atmospheric conveyance chamber (see, e.g., Patent Document 1).
Patent Document 1: Japanese Patent Laid-Open Publication No. 2010-182906
In the relate art, the substrate is cooled by making cooling water flow in the cooling table where the substrate is placed using a time until the interior of the intermediate conveyance chamber is turned into the atmospheric pressure from the vacuum atmosphere. In the substrate processing apparatus that requires a cooling system including the cooling table as described above, there are problems in that the structure is complicated and the volume of the intermediate conveyance chamber increases to enlarge the apparatus. There is also a problem in that, due to the necessity of the cooling system, the costs of the substrate processing apparatus increase.
Conventionally, the purge gas introduced into the intermediate conveyance chamber in order to switch the interior of the intermediate conveyance chamber from the vacuum atmosphere to the atmospheric pressure has been used only for switching the interior of the intermediate conveyance chamber from the vacuum atmosphere to the atmospheric pressure. Thus, if the purge gas may be used for cooling the substrate, a configuration, which does not require a cooling apparatus such as, for example, the cooling table, may be simply implemented. Meanwhile, conventionally, the purge gas is introduced into the intermediate conveyance chamber through a brake filter in order to suppress particles within the intermediate conveyance chamber from being attached to the substrate by being blown up by the purge gas. However, if the purge gas may be introduced into the intermediate conveyance chamber without using the brake filter, the costs of the substrate processing apparatus may be reduced.
In the intermediate conveyance chamber, when a substrate processed in the vacuum processing chamber and heated to a predetermined temperature is placed on the cooling table, the substrate is delivered between a substrate conveyance apparatus that conveys the substrate and a lifting pin provided on the cooling table. In a state where the lifting pin supports the substrate, the peripheral portion of the substrate may be sagged more downwardly than the central portion of the substrate (i.e., in an upwardly convex arc shape) due to the weight of the substrate itself. Further, the central portion of the substrate is hardly cooled compared to the peripheral portion. Thus, when the substrate is placed on the cooling table in the arc shape and held in that state, the peripheral portion, which is easily cooled, is in contact with the cooling table to be further cooled, but the central portion is in a floating state from the cooling table not to be cooled, so that a temperature distribution generated on the substrate increases, which may cause deformation on the substrate. The deformation of the substrate may generate scratch on the rear surface of the substrate and damage a pattern (element) formed on the front surface of the substrate.
It is considered that the problems described above have become pronounced due to enlargement of substrates in recent years. As a method for handling these problems, a method of delaying the substrate cooling rate is considered, but in this method, throughput is reduced (productivity is lowered). Thus, what is demanded is a method of rapidly cooling a substrate while suppressing the deformation of the substrate.
An object of the present disclosure is to provide a substrate processing apparatus provided with a processing chamber for cooling a substrate in which the configuration of the processing chamber is capable of being simplified and miniaturized. Another object of the present disclosure is to provide a substrate processing apparatus which is capable cooling a substrate while suppressing deformation of the substrate without degrading throughput. Still another object of the present disclosure is to provide a substrate cooling member disposed in a processing chamber so as to cool a substrate and to provide a substrate processing method using the substrate cooling member.
In order to solve the problems described above, according to the present disclosure, there is provided a substrate cooling member including a plurality of gas injection nozzles formed on one flat plate face of the substrate cooling member which has a flat plate shape. The plurality of gas injection nozzles are configured to inject a gas toward a substrate so as to cool the substrate. Each of the plurality of gas injection nozzles includes: a cylindrical space which is opened in the one flat plate face of the substrate cooling member; and a nozzle hole which is opened in a circular bottom wall that defines the space, to inject the gas toward the space. When the gas is injected toward the substrate from the nozzle hole through the space in a state where the one flat plate face, which is formed with the plurality of gas injection nozzles in the substrate cooling member, faces a flat plate face of the substrate, a swirling flow is generated in the gas injected from the nozzle hole within the space so as to cool the substrate.
In the present disclosure the gas injected from the nozzle hole may generate a flow swirling in a plane orthogonal to the one flat plate face in the space.
In the present disclosure, the nozzle hole may inject the gas in a direction substantially orthogonal to the bottom wall that defines the space.
In the present disclosure, a portion where a side wall and the bottom wall that define the space intersect with each other is formed as a curved face having a predetermined curvature.
In the present disclosure, a protrusion may be formed at a center of the circular bottom wall that defines the space to protrude to the space, and the nozzle hole may be opened in the protrusion.
In the present disclosure, a portion where the bottom wall that defines the space and a side wall of the protrusion intersect with each other is formed as a curved face having a predetermined curvature.
In the present disclosure, assuming that a diameter of the space is D, a depth of the space is h, and a clearance between the one flat plate face formed with the gas injection nozzle and the flat plate face of the substrate is CL, a relation of 1.63<D/(h+CL)<2.57 is achieved.
In the present disclosure, the substrate cooling member may further includes a buffer chamber communicated with the plurality of nozzle holes, in which a gas supplied to the buffer chamber may be injected from the plurality of nozzle holes.
In the present disclosure, the buffer chamber may be divided to a plurality of blocks by a partition, and gas support ports may be formed to independently supply a gas to the plurality of blocks, respectively.
In the present disclosure, the plurality of blocks may be a first block facing a central portion of the substrate and a second block provided in outer periphery of the first block.
In the present disclosure, the plurality of gas injection nozzles may be provided in a region facing a central portion of the substrate.
In order to solve the problems described above, according to the present disclosure, there is provided a substrate processing apparatus including: a substrate processing chamber in which a predetermined processing accompanying a substrate temperature rise is performed on a substrate; and a substrate cooling chamber in which the substrate processed in the substrate processing chamber is cooled. The substrate cooling chamber includes: a support member configured to support the substrate, and a substrate cooling member including a plurality of gas injection nozzles formed on one flat plate face of the substrate cooling member which has a flat plate shape. The plurality of gas injection nozzles are configured to inject a gas toward the substrate supported on the support member to cool the substrate. Each of the plurality of gas injection nozzles includes: a cylindrical space which is opened in the one flat plate face of the substrate cooling member, and a nozzle hole which is opened in a circular bottom wall that defines the space, to inject the gas toward the space. When the gas is injected toward the substrate from the nozzle hole through the space in a state where the one flat plate face, which is formed with the plurality of gas injection nozzles in the substrate cooling member, faces a flat plate face of the substrate, a swirling flow is generated in the gas injected from the nozzle hole within the space so as to cool the substrate.
In the present disclosure, the substrate cooling chamber may be configured such that an interior of the substrate cooling chamber is configured to be selectively switched to an atmospheric pressure atmosphere or a vacuum atmosphere, so as to convey the substrate between a processing chamber which is under a vacuum atmosphere and a processing chamber which is under an atmospheric atmosphere. The substrate cooling member may be configured to inject a gas, which is introduced into the substrate cooling chamber in order to switch the substrate cooling chamber from the vacuum atmosphere to the atmospheric pressure atmosphere, from the plurality injection nozzles to cool the substrate.
In the present disclosure, the processing chamber which is under the vacuum atmosphere may be the substrate processing chamber or a first substrate conveyance chamber disposed between the substrate processing chamber and the substrate cooling chamber in which a first conveyance apparatus is disposed to convey the substrate between the processing chamber and the substrate cooling chamber, and the processing chamber which is under the atmospheric atmosphere may be a second substrate conveyance chamber in which a second conveyance apparatus is disposed to convey the substrate between a container accommodating the substrate and the substrate cooling chamber.
In order to solve the problems described above, according to the present disclosure, there is provided a substrate processing apparatus including: a substrate processing chamber maintained under a vacuum atmosphere, and configured to perform a predetermined processing accompanying a substrate temperature rise on a substrate accommodated therein; a substrate carry-in chamber maintained under an atmospheric pressure atmosphere, in which the substrate to be processed in the substrate processing chamber is carried into the substrate carry-in chamber from outside; and an intermediate conveyance chamber having an interior configured to be selectively switched to the atmospheric pressure atmosphere or the vacuum atmosphere so as to carry the substrate between the processing chamber which is under the vacuum atmosphere and the substrate carry-in chamber which is under the atmospheric atmosphere. The intermediate conveyance chamber includes: a support member configured to support the substrate; a substrate cooling member including a plurality of gas injection nozzles formed on one flat plate face of the substrate cooling member which has a flat plate shape. The plurality of gas injection nozzles are configured to inject a gas toward a substrate supported on the support member. Each of the plurality of gas injection nozzles includes: a cylindrical space which is opened in the one flat plate face of the substrate cooling member, and a nozzle hole which is opened in a circular bottom wall that defines the space, to inject the gas toward the space. When the gas is injected toward the substrate from the nozzle hole through the space in a state where the one flat plate face, which is formed with the plurality of gas injection nozzles in the substrate cooling member, faces a flat plate face of the substrate, a swirling flow is generated in the gas injected from the nozzle hole within the space so as to cool the substrate, and at the same time, the intermediate conveyance chamber is switched from the vacuum atmosphere to the atmospheric pressure atmosphere.
In the present disclosure, the substrate processing chamber may be a plasma processing chamber configured to perform a plasma processing on the substrate.
In the present disclosure, the gas injected from the nozzle hole may generate a flow swirling in a plane orthogonal to the one flat plate face in the space.
In the present disclosure, the nozzle hole may inject the gas in a direction substantially orthogonal to the bottom wall that defines the space.
In the present disclosure, each of the plurality of gas injection nozzles may include a protrusion formed to protrude to the space at a center of the circular bottom wall that defines the space, and the nozzle hole may be opened in the protrusion.
In the present disclosure, assuming that a diameter of the space is D, a depth of the space is h, and a clearance between the one flat plate face formed with the gas injection nozzle and the flat plate face of the substrate is CL, a relation of 1.63<D/(h+CL)<2.57 may be achieved.
In the present disclosure, the substrate cooling member may include a buffer chamber communicated with the plurality of nozzle holes, and a gas supplied to the buffer chamber may be injected from the plurality of nozzle holes.
In the present disclosure, the buffer chamber may be divided to a plurality of blocks by a partition, and gas support ports may be formed to independently supply a gas to the plurality of blocks, respectively.
In the present disclosure, the plurality of blocks may be a first block facing a central portion of the substrate and a second block provided in outer periphery of the first block.
In the present disclosure, the buffer chamber may be divided into a plurality of blocks and a gas supply unit configured to control a gas flow rate supplied to the plurality of blocks may be provided such that a flow speed of the gas injected from the gas injection nozzles facing the central portion of the substrate supported on the support member among the plurality of gas injection nozzles is different from a flow rate of the gas injected from the gas injection nozzles facing the peripheral portion of the substrate.
In the present disclosure, the plurality of gas injection nozzles may be provided in a region facing a central portion of the substrate.
In the present disclosure, the flat plate face of the substrate cooling member may have a size substantially equal to a size of the flat plate face of the substrate supported on the support member.
In order to solve the problems described above, according to the present disclosure, there is provided a substrate processing method that cools a substrate by injecting a gas toward the substrate from a plurality of gas injection nozzles using a substrate cooling member including the plurality of gas injection nozzles formed on one flat plate face of the substrate cooling member which has a flat plate shape. The gas is injected toward the substrate from the gas injection nozzles in a state where the one flat plate face, which is formed with the plurality of gas injection nozzles in the substrate cooling member, faces a flat plate face of the substrate, and a swirling flow is generated in the gas in a plane orthogonal to the flat plate face of the substrate to cool the substrate.
In the present disclosure, a cylindrical space may be formed such that the plurality of gas injection nozzles are opened in the one flat plate face of the substrate cooling member, and the plurality of gas injection nozzles may be opened in a circular bottom wall defining the space to form nozzles holes that inject the gas toward the space such that the swirling flow is generated in the space.
In the present disclosure, the gas may be injected toward the substrate from the plurality of gas injection nozzles using the substrate cooling member which is provided with the plurality of gas injection nozzles in a region facing a central portion of the substrate.
In the present disclosure, the central portion of the substrate may have a radius within a range of ½ of a radius of the substrate from a center of the substrate.
In the present disclosure, the substrate cooling member may be disposed within a processing chamber configured to be selectively switched to an atmospheric pressure atmosphere or vacuum atmosphere, and the gas may be injected from the plurality of gas injection nozzles in the processing chamber which is under the vacuum atmosphere so that the substrate is cooled and at the same time, an interior of the processing chamber is switched to the atmospheric pressure atmosphere.
In the present disclosure, while the gas is injected from the plurality of gas injection nozzles toward the substrate in a state where the substrate is supported on a support member provided in the processing chamber, the support member may be moved down into a cooling table provided in the processing chamber so that the substrate is placed on the cooling table to be cooled.
In the present disclosure, cooling water is circulated in the cooling table.
In the present disclosure, the gas is injected toward a substrate from the substrate cooling member, and a swirling flow is generated in the injected gas so that the substrate is efficiently cooled. This makes a conventional water cooling system needless which enables simplification of the structure of the processing chamber for cooling the substrate so that the processing chamber may be miniaturized. Further, miniaturization and cost reduction of the substrate processing apparatus become possible. In addition, in the case of the substrate processing apparatus which is provided with the processing chamber, of which the atmosphere is adjusted between a vacuum atmosphere and an atmospheric pressure atmosphere, the purge gas introduced into the processing chamber when the processing chamber is switched from the vacuum atmosphere to the atmospheric pressure atmosphere may be used for cooling the substrate. This makes the brake filter, which has been conventionally required for introducing a purge gas into a processing chamber, needless and thus, enables cost reduction of the substrate processing apparatus. In the present disclosure, a plurality of gas injection nozzles are provided in a region facing a central portion of the substrate so as to inject the gas to the substrate. This assists the cooling of the central portion of the substrate which is hardly cooled as compared to the peripheral portion of the substrate. Thus, it is possible to cool the substrate while suppressing deformation of the substrate without degrading throughput.
Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying descriptions. Here, as a substrate processing apparatus according to the present disclosure, a plasma processing apparatus that performs a plasma processing on a semiconductor wafer (hereinafter, referred to as a “wafer”) will be discussed.
In the plasma processing apparatus 10, a loader module 14 is disposed adjacent to the load ports 16 so as to perform carry-in/carry-out of the wafers with respect to the FOUPS, and a positioning mechanism 17 is disposed adjacent to the loader module 14 so as to perform positioning of the wafers W. In addition, two load-lock chambers 13 are disposed at a side opposite to the load ports 16 with the loader module 14 being interposed therebetween. The interior of the loader module 14 is always under an atmospheric pressure atmosphere, and a wafer conveyance apparatus 18 is disposed within the loader module 14. The wafer conveyance apparatus 18 conveys wafers W among the FOUPs disposed in the load ports 16, the positioning mechanism 17, and the load-lock chambers 13.
The load-lock chambers 13 are configured to switch the interiors thereof between the vacuum atmosphere and the atmospheric pressure atmosphere, and the interiors of the load-lock chambers 13 become the atmospheric pressure atmosphere when they are communicated with the loader module 14, and become the vacuum atmosphere when they are communicated with the vacuum conveyance chamber 11 to be described later. Meanwhile, the detailed configuration of the load-lock chambers 13 will be described later.
A vacuum conveyance chamber 11, which has an octagonal shape in a plan view, is disposed at the side opposite to the, loader module 14 with the load-lock chambers 13 being interposed therebetween, and five vacuum processing chambers are radially disposed around the vacuum conveyance chamber 11 to be connected with the vacuum conveyance chamber 11. The interior of the vacuum conveyance chamber 11 is always maintained at a predetermined vacuum degree, and a scalar robot 15 is disposed therein so as to convey the wafers W. In addition, the interior of each of the vacuum processing chambers 12 is maintained at a predetermined vacuum degree. The vacuum processing chambers accommodate wafers W therein to perform a predetermined plasma processing such as, for example, a plasma etching processing.
Meanwhile, although not illustrated in
In the plasma processing apparatus 10, a plasma processing is performed on a wafer W in the following order. A plurality of wafers W are simultaneously processed in the plasma processing apparatus 10. Here, however, descriptions will be made on a processing of one wafer W according to a time sequence.
First, when a FOUP is disposed in a load port 16, a gate valve provided in the load port 16 holds and opens the closure of the FOUP, the wafer conveyance apparatus 18 takes out a wafer W from the FOUP, and holds and carries the wafer W into the positioning mechanism 17. The wafer W positioned by the positioning mechanism 17 is carried into a load-lock chamber 13, which is maintained at the atmospheric pressure atmosphere, by the wafer conveyance apparatus 18. At this time, the vacuum conveyance chamber 11 side gate valve of the load-lock chamber 13 is closed. After the loader module 14 side gate valve of the load-lock chamber 13 is closed, the load-lock chamber 13 is decompressed to a predetermined vacuum degree.
When the interior of the load-lock chamber 13 reaches the predetermined vacuum degree, the vacuum conveyance chamber 11 side gate valve is opened, and the scalar robot 15 carries the wafer W out of the load-lock chamber 13 and carries the held wafer W into a vacuum processing chamber 12 so that a predetermined plasma processing is performed on the wafer W in the vacuum processing chamber 12. After the processing in the vacuum processing chamber 12 is terminated, the wafer W has a temperature raised by the plasma processing. The wafer W having the raised temperature is carried out from the vacuum processing chamber 12 and carried into the load-lock chamber 13 by the scalar robot 15. The vacuum conveyance chamber 11 side gate valve of the load-lock chamber 13 is closed, and a purge gas such as, for example, nitrogen gas, is introduced into the load-lock chamber 13 so as to develop the atmospheric pressure atmosphere in the load-lock chamber 13. In the present exemplary embodiment, the purge gas is used for cooling the wafer W. This will be described in detail below.
When the interior of the load-lock chamber 13 becomes the atmospheric pressure atmosphere and the wafer W is cooled to the predetermined temperature, the loader module 14 side gate valve of the load-lock chamber 13 is opened, and the wafer conveyance apparatus 18 takes out the wafer W from the load-lock chamber 13 and carries the wafer W into a predetermined position of the FOUP. In this way, the processing performed on the wafer W in the plasma processing apparatus 10 is terminated.
Lifting pins 23 serving as support members for supporting a wafer W are provided to be capable of being moved up and down by a lifting device (not illustrated) through the bottom wall of the load-lock chamber 13 in the vertical direction (in the direction orthogonal to the bottom wall). Meanwhile, illustration of a vacuum sealing structure around the lifting pins 23 is omitted in
The gas injection member 25 serving as a substrate cooling member is disposed at the ceiling side within the load-lock chamber 13. The gas injection member 25 is supplied with a purge gas such as, for example, nitrogen gas N2, from a gas supply source (not illustrated) through a gas supply tube 26. The wafer W processed in the vacuum processing chamber 12 is carried into the load-lock chamber 13 and delivered to the lifting pins 23 so that the lifting pins 23 hold the wafer W at the cooling treatment position. When the gate valve 21 is closed, the gas injection member 25 injects the purge gas toward the wafer W supported on the lifting pins 23. As a result, heat exchange is performed between the purge gas and the wafer W so that the wafer W is cooled to a predetermined temperature, and at the same time, the interior of the load-lock chamber 13 is switched from the vacuum atmosphere to the atmospheric pressure atmosphere.
The disc member 31 may have a diameter which is the same as that of the wafer W, which allows the purge gas to be injected to the entire surface of the wafer W so as to cool the wafer W.
A recess 32 is formed on the top face side of the disc member 31. The top face of the disc member 31 is covered by a disc-shaped cover member 33 so that a buffer chamber 34 is formed between the disc member 31 and the cover member 33. A gas supply tube 26 is attached to the cover member 33, and the purge gas supplied to the gas injection member 25 through the gas supply tube 26 is substantially uniformized in pressure within the buffer chamber 34 and then injected from the gas injection nozzles 35. Although
In the gas injection nozzle 35, a region where the side wall 51 and the bottom wall 52 intersect with each other is formed in a curved face 54 having a predetermined curvature. Similarly, a region where the side wall of the protrusion 53 and the bottom wall 52 intersect with each other is formed in a curved face 55 having a predetermined curvature. Forming the protrusion 53 and the curved faces 54 and 55 is not necessarily required. However, as described below, forming the protrusion 53 and the curved faces 54 and 55 presents an effect of facilitating the generation of a vortex in the purge gas injected from the nozzle hole 42.
In this way, the vortex of the purge gas including the vertical flows, that is, the flows of the purge gas swirling in a plane orthogonal to the surface of the wafer W is generated in the vortex generating chamber 41, and the wafer W is cooled by the heat exchange between the wafer W and the purge gas. By generating the vortex of the purge gas, the number of times of impingement of the purge gas against the wafer W may be increased until the purge gas is discharged from the clearance between the bottoms surface of the gas injection member 25 and the wafer W, so that the wafer W can be efficiently cooled using the purge gas. In such a case, when the flows of the purge gas forming the vortex are slow, the heat exchange may be efficiently performed.
Meanwhile, the “vortex of the purge gas” in the present exemplary embodiments neither indicates that the full amount of the purge gas should form the vortex, nor indicates that the purge gas should form a swirling flow that circulates many times, i.e. over a large number of times. The “vortex of the purge gas” refers to a flow of a purge gas, at least a part of which impinges against the wafer W again after the purge gas impinges against the wafer W and which is generated within the vortex generating chamber, as compared with a flow which is rapidly discharged from the surface of the wafer W after impinging against the wafer W.
As injection conditions of the purge gas from the nozzle hole 42 into the vortex generating chamber 41, for example, the vortex of the purge gas should be well formed uniformly within the vortex generating chamber 41, and the flow speed of the purge gas should not be excessively increased. The reason why the flow speed of the purge gas should not be excessively increased is that when the flow speed is excessively increased, the purge gas may be discharged from the clearance between the bottom face of the gas injection member 25 and the wafer W without sufficient heat exchange, and the purge gas discharged as such may wind up particles attached to, for example, the bottom wall of the load-lock chamber 13.
The shape of the gas injection nozzle 35 and the flow rate of the purge gas are properly determined so as to satisfy the conditions described above and also in consideration of the inner volume of the load-lock chamber 13 or the throughput of the plasma processing apparatus 10. The shape of the gas injection nozzle 35 and the flow rate of the purge gas are designed such that when the temperature of the wafer W is reduced from 250° C. to 150° C., a temperature falling rate of about 4° C./sec to about 9° C./sec is obtained. Thus, hereinafter, descriptions will be made on simulation results for purge gas flows which are helpful in designing the shape of the gas injection nozzle 35.
The parameters represented in respective drawings of
The result obtained in the parameter condition represented in
In
Meanwhile, the gas flows, which are indicated approximately as yellow-yellow green-light blue in the original drawing as described above, are difficult to indicate on the drawing using flow speed lines. Thus, for example, in the case where the tube diameter d is 4 mm in
Meanwhile, in order to examine which parameter has an influence on the flow of the purge gas when simulating the flow of the purge gas, it is necessary to set the parameter as a variable parameter and then to fix the other parameters. For this reason, from the simulation results of
In
The result obtained in the parameter conditions set here is that although a vortex is generated when the flow rate L is in a range of 0.5 L/min to 3 L/min, in particular, a favorable vortex having a low flow speed is generated when the flow rate L is in a range of 0.5 L/min to 1.5 L/min, and the flow speed of the vortex increases and the density of flow speed lines of the gas is reduced when the flow rate L is in a range of 2.0 L/min to 3.0 L/min.
From the simulation results of
Meanwhile, a specific shape of the gas injection nozzle 35 is properly designed in consideration of, for example, an amount of gas to be introduced into a load-lock chamber 13 within a predetermined time, and a cooling rate of the wafer W in which a throughput in the entire plasma processing apparatus 10 is taken into consideration. For example, when the simulation results of
By reducing the thickness of the gas injection member 25, the weight reduction and cost reduction may be achieved and the load-lock chamber 13 may be configured compactly. However, when the thickness of the gas injection member 25 is reduced, it may be impossible to take the depth h of the vortex generating chamber 41 sufficiently. Thus, when the ratio of D/(h+CL) is to be set as described above, it is necessary to reduce the diameter D of the vortex generating chamber 41 as the height h is reduced. In such a case, for example, increasing the number of gas injection nozzles 35 to be formed in the disc member 31 or reducing the tube diameter d of the nozzle holes 42 may be needed.
As described above, in the present exemplary embodiment, when the gas purge gas is injected to the surface of a wafer W from the injection nozzles 35 so as to cool the wafer W, a vortex is generated in the purge gas to increase the number of times of impingement between the purge gas and the wafer W, and to perform heat exchange between the purge gas and the wafer W so that the wafer W may be efficiently cooled. At the same time, since the load-lock chamber 13 may be switched from a vacuum atmosphere to an atmospheric pressure atmosphere, the purge gas, which has been used only for switching the interior of the load-lock chamber 13 from the vacuum atmosphere to the atmospheric pressure atmosphere in the related art, may be effectively used. In addition, since a brake filter, which has been used in the related art, becomes needless, the costs of the plasma processing apparatus 10 may be reduced. Furthermore, since a water cooling apparatus, which includes a water cooling table and has been conventionally used for cooling a wafer W, becomes needless, the structure of the load-lock chamber 13 may be simplified to reduce the internal volume thereof. In this way, occurrence of trouble of water leakage may be reduced, and further, the costs of the plasma processing apparatus 10 may also be reduced.
In the gas injection member 25A, each of the gas flow rates supplied through the gas supply tubes 26A and 26B from the gas supply units (not illustrated) is adjusted, so that the gas flow rate injected from the nozzle holes 42 of the gas injection nozzles 35 communicated with the first buffer chamber 34A and the gas flow rate injected from the nozzle holes 42 of the gas injection nozzles 35 communicated with the second buffer chamber 34B may be independently controlled. For example, when a gas flow rate control is performed, for example, so as to increase the gas flow rate injected from the nozzles holes 42 facing the central portion of the wafer W which is hardly cooled and communicated with the first buffer chambers, to be higher than the gas flow rate injected from the nozzle holes 42 communicated with the second buffer chamber 34B, the in-plane uniformity of the wafer W in cooling may be enhanced.
Although the gas injection member 25A is configured to include the buffer chamber with two blocks of the first buffer chamber 34A and the second buffer chamber 34B, it is possible to employ a configuration in which more blocks are formed and gas supply is independently performed with respect to each of the blocks. In addition, it is possible to employ a configuration in which the gas flow rate injected from the nozzle holes 42 is controlled for each gas injection nozzle 35 without forming the buffer chamber. Then, by performing a more detailed gas flow rate control, the purge gas may be efficiently used to enhance the uniformity in cooling the wafer W.
In addition, the gas injection nozzles 35 are formed at regular intervals in the gas injection member 25 or 25A. Without being limited thereto, however, some of the plurality of gas injection nozzles 35 may be arranged at regular intervals but the other gas injection nozzles may be arranged at different intervals. In addition, some of the gas injection nozzles 35 may have a size which is different from that of the other gas injection nozzles.
Meanwhile, the lifting pins 23 are configured to hold the central side of the wafer W since the scalar robot 15 is configured to hold a portion in the vicinity of the outer periphery of the wafer W in consideration of delivery of the wafer W between the lifting pins 23 and the scalar robot 15 and in order to convey the wafer W processed in the vacuum processing chamber 12 in a stably held state without dropping the wafer W (see
Especially, when the size of the wafer W is increased, the peripheral portion of the wafer W is apt to be sagged downwardly as compared to the central portion (in an upwardly convex arc shape) due to the self-weight of the wafer W, as illustrated in
Thus, as illustrated in
Here, when the gas is supplied only to the central portion of the wafer W to cool the wafer W, the cooling rate of the wafer W is reduced with just that. Thus, the placing table 37 is provided in the load-lock chamber 13. As illustrated in
Meanwhile, the wafer W cooling method illustrated in
In the gas injection nozzle 35A of
A gas injection nozzle 35C of
Meanwhile, as a modified example of the gas injection nozzle 35C, even with a configuration in which a nozzle is provided in the bottom face of the disc member 31 to inject the purge gas such that a spiral vortex is formed in the clearance between the bottom face of the disc member 31 and the wafer W without forming the vortex generating chamber 61, the load-lock chamber 13 may be switched from the vacuum atmosphere to the atmospheric pressure atmosphere while cooling the wafer W by the swirl vortex.
Although the exemplary embodiments of the present disclosure have been described above, the present disclosure is not limited thereto. For example, in the exemplary embodiments described above, a plasma processing apparatus is exemplified as the substrate processing apparatus. Without being limited thereto, however, the present disclosure may be applied to a substrate processing apparatus including a substrate processing chamber in which a processing of increasing a substrate temperature is performed on a substrate, and an intermediate conveyance chamber of which the interior may be switched between a vacuum atmosphere and an atmospheric pressure atmosphere in order to convey the substrate processed in the substrate processing chamber to the outside which is under the atmospheric pressure. That is, the gas injection member 25 may be disposed in the intermediate conveyance chamber provided in the substrate processing apparatus.
In addition, in the above-described exemplary embodiments, it has been described that the wafer W supported on the lifting pins 23 is cooled by supplying the purge gas from the gas injection member 25 to the wafer W. However, a placing table, on which the wafer W is placed, may be provided in the load-lock chamber 13 in order to stabilize the posture of the wafer W during the cooling processing, and cooling by the gas injection member 25 may be performed in the state where the wafer W is supported on the placing table. At this time, when, for example, a water cooling table, which is excellent in cooling capability, is used as the placing table, the cooling action by the water cooling table and the cooling action by the gas injection member 25 may be combined with each other to increase the cooling rate, thereby cooling the wafer W with a high speed.
In the above-described exemplary embodiments, it has been described that a processed substrate is cooled in a vacuum atmosphere. However, the gas injection member 25 may be used even in a substrate processing apparatus that performs a cooling processing, under the atmospheric pressure, on a substrate which has been heated by a processing performed under the atmospheric pressure. Even in this case, as compared with a structure employing a conventional water cooling table, it is advantageous in that trouble such as water leakage does not occur, the apparatus structure may be simplified to enhance flexibility in designing the apparatus, and the apparatus costs may be reduced.
In the above-described exemplary embodiments, a semiconductor wafer is exemplified as the substrate. Without being limited thereto, however, the object to be cooled by the gas injection member 25 may be any other substrate such as, for example, a glass substrate for a flat panel display (FPD) or a ceramic substrate.
The application is based on and claims priority from Japanese Patent Application Nos. 2012-245360 and 2013-122587, filed on Nov. 7, 2012 and Jun. 11, 2013, with the Japan Patent Office, the disclosures of which are incorporated herein in their entirety by reference.
Number | Date | Country | Kind |
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2012-245360 | Nov 2012 | JP | national |
2013-122587 | Jun 2013 | JP | national |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/JP2013/079652 | 10/25/2013 | WO | 00 |