Substrate processing method and substrate processing apparatus

Abstract

To provide a substrate processing method capable of oxidizing a molybdenum film in a method different from conventional methods and removing an oxidized portion of the molybdenum film from the substrate while leaving an unoxidized portion of the molybdenum film in the substrate, and a substrate processing device.SOLUTION: A substrate processing method includes an oxidizing step, a first transporting step, and an etching step. The oxidizing step changes a surface layer of a molybdenum film to molybdenum trioxide by heating a plurality of substrates W in an oxidization space SO while supplying an oxygen gas or an ozone gas to the plurality of substrates W. The first transporting step transports a plurality of substrates W in the oxidization space SO to an etching space SE in a substrate processing device 1 different from the oxidization space SO. The etching step dissolves a surface layer that has changed to molybdenum trioxide in an etching liquid while leaving portions other than the surface layer of the molybdenum film in the substrate W by supplying the etching liquid to the plurality of substrates W in the etching space SE.SELECTED DRAWING: Figure 4A

Description

Technical Field

[0001] The present invention relates to a substrate processing method and a substrate processing apparatus for processing a substrate. The substrate includes, for example, a semiconductor wafer, a substrate for a FPD (Flat Panel Display) such as a liquid crystal display device or an organic EL (electroluminescence) display device, a substrate for an optical disk, a substrate for a magnetic disk, a substrate for a magneto-optical disk, a substrate for a photomask, a ceramic substrate, a substrate for a solar cell, and the like.

Background Art

[0002] Patent Document 1 discloses forming a molybdenum oxide portion by oxidizing a molybdenum layer by oxygen ion implantation or oxygen plasma doping, and removing the molybdenum oxide portion from the substrate while leaving a non-oxidized molybdenum layer on the substrate by wet etching in which a liquid such as an ammonia solution is supplied to the substrate.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Although Patent Document 1 discloses oxidizing a molybdenum layer by oxygen ion implantation or oxygen plasma doping, it does not disclose oxidizing a molybdenum layer by other methods. When it is desired to oxidize a molybdenum layer by other methods, the disclosure of Patent Document 1 cannot meet such a demand.

[0005] One of the objectives of the present invention is to provide a substrate processing method and a substrate processing apparatus that can oxidize a molybdenum film in a manner different from conventional methods, and that can remove the oxidized portion of the molybdenum film from the substrate while leaving the unoxidized portion of the molybdenum film on the substrate. [Means for solving the problem]

[0006] One embodiment of the present invention provides a substrate processing method comprising: an oxidation step in which oxygen gas or ozone gas is supplied to a plurality of substrates arranged in an oxidation space within a substrate processing apparatus, and the plurality of substrates in the oxidation space are heated, thereby changing the surface layer of the molybdenum film formed on each of the plurality of substrates to molybdenum trioxide without changing the portion of the molybdenum film other than the surface layer to molybdenum trioxide; a first transport step in which the plurality of substrates in the oxidation space are transported to an etching space within the substrate processing apparatus, which is different from the oxidation space; and an etching step in which an etching solution is supplied to the plurality of substrates in the etching space, thereby dissolving the surface layer that has been changed to molybdenum trioxide in the etching solution, while leaving the portion of the molybdenum film other than the surface layer on each of the plurality of substrates.

[0007] In this method, multiple substrates are placed in the oxidation space of the substrate processing apparatus, and the multiple substrates are heated while oxygen gas or ozone gas is supplied to them. As a result, oxygen atoms in the oxygen gas or ozone gas combine with molybdenum, and the surface layer of the molybdenum film changes to molybdenum trioxide. Subsequently, the multiple substrates are transported from the oxidation space of the substrate processing apparatus to the etching space, and an etching solution is supplied to the multiple substrates in the etching space. The molybdenum trioxide dissolves in the etching solution. Therefore, the surface layer of the molybdenum film that has changed to molybdenum trioxide is etched, and the parts of the molybdenum film other than the surface layer that have not changed to molybdenum trioxide remain on the substrate.

[0008] In this way, by heating the substrate while supplying oxygen gas or ozone gas to the substrate, the molybdenum film formed on the substrate can be oxidized. Furthermore, since the molybdenum film is oxidized and etched within a single substrate processing apparatus, the time required for transporting the substrate can be reduced compared to when the oxidation of the molybdenum film and the etching of the molybdenum oxide film are performed in separate substrate processing apparatuses. In addition, since multiple substrates are oxidized and etched together, the time required for oxidation and etching can be reduced compared to when multiple substrates are oxidized and etched one by one.

[0009] Oxygen gas and ozone gas are oxygen atom-containing gases that contain oxygen atoms. The oxygen atom-containing gas may be supplied to the substrate by filling the oxidation space with the oxygen atom-containing gas, or by discharging the oxygen atom-containing gas within the oxidation space. In the latter case, the oxidation space may be filled with oxygen atom-containing gas, or gases other than oxygen atom-containing gas may be present in the oxidation space. In other words, the oxygen atom-containing gas can be supplied to the substrate in any way, as long as a sufficient amount of oxygen atoms to convert molybdenum to molybdenum trioxide is supplied to the surface of the molybdenum film.

[0010] In the above embodiment, at least one of the following features may be added to the substrate processing method.

[0011] The oxidation process involves supplying the ozone gas to the multiple substrates in the oxidation space while heating the multiple substrates in the oxidation space.

[0012] This method involves heating the substrate while supplying ozone gas instead of oxygen gas. Therefore, compared to heating the substrate while supplying oxygen gas, the surface layer of the molybdenum film can be efficiently converted to molybdenum trioxide. This reduces the time required to convert the surface layer of the molybdenum film to molybdenum trioxide, thereby increasing the throughput (number of substrates processed per unit time) of the substrate processing equipment.

[0013] The etching solution is a water-containing solution with water as its main component.

[0014] In this method, a water-containing solution, primarily composed of water, is supplied to the substrate for etching. Molybdenum trioxide dissolves in water, while molybdenum itself is insoluble or hardly soluble in water. Therefore, the surface layer of the molybdenum film, which has been converted to molybdenum trioxide, can be removed from the substrate without the use of chemicals. This simplifies the treatment of wastewater and reduces the environmental burden compared to cases where the etching solution is a chemical.

[0015] The water-containing solution equivalent to the etching solution may be pure water or other water (a liquid with a volume concentration of 100% or substantially 100% water), or a liquid with a volume concentration of 90% or more but less than 100% water. In the latter case, the chemical may be dissolved in the water-containing solution at low concentrations. In this case, the surface layer of the molybdenum film converted to molybdenum trioxide can be removed from the substrate in a shorter time.

[0016] The substrate processing method further includes a second transport step of transporting the plurality of substrates in the etching space to the oxidation space, and the substrate processing method performs one cycle including the oxidation step, the first transport step, the etching step, and the second transport step multiple times.

[0017] In this method, after supplying etching solution to multiple substrates in an etching space, the multiple substrates are transported to an oxidation space, and the multiple molybdenum films formed on the multiple substrates are oxidized. In other words, the oxidation of the molybdenum film and the etching of the molybdenum oxide film are repeated alternately multiple times. This makes it possible to gradually reduce the thickness of the molybdenum film and adjust the thickness of the molybdenum film in stages.

[0018] When a single cycle including an oxidation step, a first transport step, an etching step, and a second transport step is performed multiple times, the thickness of the molybdenum oxide film formed in the oxidation step may be the same each time, or it may differ among the multiple oxidation steps. Similarly, the amount of reduction in the thickness of the molybdenum film in the etching step, i.e., the thickness of the molybdenum oxide film dissolved in the etching solution, may be the same each time, or it may differ among the multiple etching steps.

[0019] The oxidation step involves heating the multiple substrates in the oxidation space while holding them with a substrate holder and supplying oxygen gas or ozone gas to the multiple substrates in the oxidation space; the first transport step involves transporting the multiple substrates in the oxidation space to the etching space by moving the substrate holder from the oxidation space to the etching space; and the etching step involves supplying the etching solution to the multiple substrates in the etching space while holding them with the substrate holder.

[0020] This method involves oxidizing multiple molybdenum films while holding multiple substrates in a substrate holder, then transporting the multiple substrates from the oxidation space to the etching space to etch the multiple molybdenum oxide films. In other words, there is no need to move the multiple substrates held in one substrate holder to another substrate holder, nor is there a need to provide multiple substrate holders, in order to oxidize the molybdenum films, transport the substrates from the oxidation space to the etching space, and etch the molybdenum oxide films. This increases the throughput of the substrate processing equipment.

[0021] The first transport step involves moving the first inner partition, which forms part of the oxidation space and part of the etching space, and then transporting the plurality of substrates in the oxidation space to the etching space through the space where the first inner partition was located.

[0022] According to this method, a first inner partition is disposed between an oxidation space and an etching space, forming a part of the contour of the oxidation space and a part of the contour of the etching space. At least a part of the oxidation space is separated from the etching space only by the first inner partition. When the first inner partition is moved, a plurality of substrates can be moved between the oxidation space and the etching space. Since the oxidation space is disposed near the etching space only through the first inner partition, the time for transporting the substrate to the etching space can be shortened, and the throughput of the substrate processing apparatus can be increased.

[0023] The substrate processing method further includes a second transport step of transporting the plurality of substrates in the etching space to the oxidation space, and a drying step of drying the plurality of substrates in the oxidation space after supplying the etching solution to the plurality of substrates.

[0024] According to this method, after supplying the etching solution to a plurality of substrates, the plurality of substrates are moved from the etching space to the oxidation space. Then, the plurality of substrates in the oxidation space are dried. That is, the oxidation space also serves as a drying space for drying the substrate, and oxidation and drying of the molybdenum film are performed on the substrate in the oxidation space. Therefore, the substrate processing apparatus can be miniaturized compared with the case where a drying space separate from the oxidation space is provided.

[0025] When one cycle including the oxidation step, the first transport step, the etching step, and the second transport step is performed multiple times, a drying step is executed on the plurality of substrates transported to the oxidation space by the second transport step after the etching step of the final cycle.

[0026] After moving a second inner partition that forms a part of a drying space in the substrate processing apparatus different from the oxidation space and the etching space and a part of the oxidation space or the etching space, a third transfer step of transferring the plurality of substrates in the etching space to the drying space through the space where the second inner partition was disposed, and a drying step of drying the plurality of substrates in the drying space after supplying the etching liquid to the plurality of substrates are further included.

[0027] According to this method, the second inner partition is disposed between the oxidation space or the etching space and the drying space. At least a part of the drying space is separated from the oxidation space or the etching space only by the second inner partition. When the second inner partition is moved, the plurality of substrates can enter and exit the drying space. Since the drying space is disposed near the oxidation space or the etching space only through the second inner partition, the time for transferring the substrates to the drying space can be shortened, and the throughput of the substrate processing apparatus can be increased. In addition, compared with the case where the oxidation space or the etching space also serves as the drying space, the structure of the substrate processing apparatus can be simplified.

[0028] When one cycle including the oxidation step, the first transfer step, the etching step, and the second transfer step is performed multiple times, the drying step is performed on the plurality of substrates transferred to the oxidation space by the third transfer step after the etching step of the final cycle.

[0029] The substrate processing method further includes a rinsing step of supplying a rinsing liquid having the same name as the etching liquid and different from the etching liquid to the plurality of substrates after supplying the etching liquid to the plurality of substrates.

[0030] This method involves supplying etching solution to multiple substrates, followed by rinsing solution to the same substrates. This allows the rinsing solution to wash away any etching solution or particles adhering to the substrates. If the etching solution and rinsing solution are different types of liquids, separate piping is required for each. However, if both liquids are of the same name, separate piping is not necessary, simplifying the structure of the substrate processing apparatus.

[0031] Another embodiment of the present invention provides a substrate processing apparatus comprising: a partition forming an oxidation space and an etching space; an oxidation means that heats the plurality of substrates in the oxidation space while supplying oxygen gas or ozone gas to the plurality of substrates arranged in the oxidation space, thereby changing the surface layer of the molybdenum film formed on each of the plurality of substrates to molybdenum trioxide without changing the portion of the molybdenum film other than the surface layer to molybdenum trioxide; a transport system that transports the plurality of substrates in the oxidation space to an etching space different from the oxidation space; and an etching means that supplies an etching solution to the plurality of substrates in the etching space, thereby dissolving the surface layer that has been changed to molybdenum trioxide in the etching solution while leaving the portion of the molybdenum film other than the surface layer on each of the plurality of substrates. This configuration can achieve the same effects as the substrate processing method described above. At least one of the features of the substrate processing method described above may be added to the substrate processing apparatus. [Brief explanation of the drawing]

[0032] [Figure 1A] This is a schematic cross-sectional view showing an example of a cross-section of a substrate before processing according to the first embodiment of the present invention. [Figure 1B] This is a schematic cross-sectional view showing an example of a cross-section of a substrate during processing according to the first embodiment of the present invention. [Figure 1C] This is a schematic cross-sectional view showing an example of a cross-section of a substrate after processing according to the first embodiment of the present invention. [Figure 2] This is a schematic plan view showing the layout of a batch-type substrate processing apparatus according to the first embodiment of the present invention. [Figure 3A] This is a schematic front view of the auxiliary transport robot. [Figure 3B] This is a schematic left side view of the auxiliary transport robot. [Figure 4A] This is a schematic cross-sectional view showing the vertical cross-section of the processing unit. [Figure 4B] This is a schematic cross-sectional view showing the vertical cross-section of the processing unit. [Figure 5] This is a process diagram illustrating an example of substrate processing according to the first embodiment of the present invention. [Figure 6A-D] This is a schematic cross-sectional view showing the state of the processing unit when an example of substrate processing shown in Figure 5 is being performed. [Figure 6E-G] This is a schematic cross-sectional view showing the state of the processing unit when an example of substrate processing shown in Figure 5 is being performed. [Figure 7] This is a schematic cross-sectional view showing a vertical cross-section of a processing unit according to a second embodiment of the present invention. [Figure 8A] This is a schematic cross-sectional view showing the state of the processing unit when an example of substrate processing according to the second embodiment of the present invention is being performed. [Figure 8B] This is a schematic cross-sectional view showing the state of the processing unit when an example of substrate processing according to the second embodiment of the present invention is being performed. [Figure 8C] This is a schematic cross-sectional view showing the state of the processing unit when an example of substrate processing according to the second embodiment of the present invention is being performed. [Figure 9] This is a schematic cross-sectional view showing a vertical cross-section of a processing unit according to a third embodiment of the present invention. [Figure 10A] This is a schematic cross-sectional view showing the state of the processing unit when an example of substrate processing according to the third embodiment of the present invention is being performed. [Figure 10B] This is a schematic cross-sectional view showing the state of the processing unit when an example of substrate processing according to the third embodiment of the present invention is being performed. [Figure 10C]This is a schematic cross-sectional view showing the state of the processing unit when an example of substrate processing according to the third embodiment of the present invention is being performed. [Figure 10D] This is a schematic cross-sectional view showing the state of the processing unit when an example of substrate processing according to the third embodiment of the present invention is being performed. [Modes for carrying out the invention]

[0033] Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0034] First, an overview of the processing of the substrate W according to the first embodiment of the present invention will be described.

[0035] Figure 1A is a schematic cross-sectional view showing an example of a cross-section of the substrate W before processing according to the first embodiment of the present invention. Figure 1B is a schematic cross-sectional view showing an example of a cross-section of the substrate W during processing according to the first embodiment of the present invention. Figure 1C is a schematic cross-sectional view showing an example of a cross-section of the substrate W after processing according to the first embodiment of the present invention.

[0036] The molybdenum film 100 is a thin film made of molybdenum formed on the surface of a substrate W, such as a semiconductor wafer. The molybdenum film 100 may also be part of a metal wiring (molybdenum wiring) electrically connected to a device formed on the substrate W, such as a transistor. The metal wiring may be a metal wiring layer placed on an interlayer insulating film, or a metal plug placed in a hole penetrating at least one interlayer insulating film, such as a via hole, or it may be both a metal wiring layer and a metal plug.

[0037] As shown in Figure 1A, the molybdenum film 100 is composed of a surface layer 102 that encompasses the entire surface 103 of the molybdenum film 100, and a bulk layer 101 that represents the portion of the molybdenum film 100 other than the surface layer 102. The surface layer 102 of the molybdenum film 100 represents a layer of constant or approximately constant thickness from the surface 103 of the molybdenum film 100. Before the substrate W is processed, the surface 103 of the molybdenum film 100 may or may not be covered by molybdenum oxide. Before the substrate W is processed, the surface 103 of the molybdenum film 100 or the surface of the molybdenum oxide may or may not be partially covered by other materials such as a resist pattern.

[0038] Figure 1A shows an example in which the surface 103 of a molybdenum film 100 is covered by a native molybdenum oxide film 104 containing molybdenum oxide (MoO2) and molybdenum trioxide (MoO3). Both molybdenum oxide and molybdenum trioxide are examples of molybdenum oxides. In the example shown in Figure 1A, part or all of the surface 103 of the molybdenum film 100 is covered by the native molybdenum oxide film 104. The native molybdenum oxide film 104 is exposed on the surface of a substrate W such as a semiconductor wafer and is in contact with the atmosphere in the space in which the substrate W is placed.

[0039] In the processing of the substrate W according to the first embodiment of the present invention, an oxidation step is performed in which the substrate W is heated while an oxygen atom-containing gas such as ozone gas is supplied to the substrate W. Ozone gas is an example of an oxygen atom-containing gas containing oxygen atoms. The oxygen atom-containing gas may be oxygen gas. If molybdenum oxide such as a native oxide film 104 is formed on the molybdenum film 100, the molybdenum oxide may be removed from the molybdenum film 100 by wet etching or dry etching before performing the oxidation step, or the oxidation step may be performed without removing the molybdenum oxide.

[0040] When performing the oxidation process, the substrate W may be heated by contact heating or non-contact heating, or by both contact heating and non-contact heating. When heating the substrate W by contact heating, the substrate W may be placed horizontally on a hot plate heated to a temperature higher than room temperature (a constant or nearly constant temperature between 15 and 30°C) with the surface of the substrate W on which the device is formed facing upwards, thereby bringing the bottom surface of the substrate W into contact with the hot plate. When heating the substrate W by non-contact heating, electromagnetic waves emitted from a heat source such as a lamp may be irradiated onto the substrate W. When performing the oxidation process, the substrate W may be in a horizontal or vertical position, or in any other position.

[0041] During the oxidation process, the molybdenum in the molybdenum film 100 is oxidized by ozone or oxygen molecules in the atmosphere in contact with the substrate W, and the surface 103 of the molybdenum film 100 changes to molybdenum trioxide. If the surface 103 of the molybdenum film 100 is covered with a molybdenum oxide such as a native oxide film 104, not only the surface 103 of the molybdenum film 100 but also the molybdenum oxide changes to molybdenum trioxide. As a result, a molybdenum oxide film 105 containing molybdenum trioxide is formed on the surface 103 of the molybdenum film 100, as shown in Figure 1B.

[0042] The molybdenum film 100 gradually changes from its surface 103 toward the interior of the molybdenum film 100 into molybdenum trioxide. The boundary between the molybdenum film 100 and the molybdenum oxide film 105 gradually shifts toward the interior of the molybdenum film 100. As a result, the thickness of the molybdenum oxide film 105 continuously increases. When the oxidation process reaches the maximum growth time, which will be described later, a molybdenum oxide film 105 of the maximum thickness, as described later, is formed on the surface 103 of the molybdenum film 100.

[0043] The molybdenum oxide film 105 is a thin film of molybdenum trioxide bonded to the molybdenum film 100. The molybdenum oxide film 105 may contain substances other than molybdenum trioxide, such as molybdenum oxide. Figure 1B shows an example where the entire surface 106 of the molybdenum oxide film 105 is flat and the thickness of the molybdenum oxide film 105 is uniform. The molybdenum oxide film 105 is thinner than the molybdenum film 100. The thickness of the molybdenum oxide film 105 may be greater than or equal to the thickness of the molybdenum film 100.

[0044] The oxidation time is defined as the time spent performing the oxidation process (the time spent heating the substrate W while bringing it into contact with an oxygen atom-containing gas such as ozone gas), and the oxidation conditions are defined as the conditions of the oxidation process excluding the oxidation time. The oxidation conditions include multiple parameters. For example, the temperature of the substrate W, the concentration of the ozone gas supplied to the substrate W, and the flow rate of the ozone gas supplied to the substrate W are included in the oxidation conditions. The oxidation time is not included in the oxidation conditions.

[0045] The oxidation conditions when the oxygen atom-containing gas is ozone gas are as follows: Specifically, the temperature of the substrate W is 150°C or higher, for example, in the range of 180-300°C. The ozone gas concentration is 50 g / m³. 3 For example, 100-200 g / m 3 The following values ​​are within the specified range. The ozone gas flow rate is 5 SLM (Standard Litter Min) or more, for example, within the range of 18 to 20 SLM. The oxidation time is 30 seconds or more, for example, within the range of 30 to 300 seconds. The etching time, described later, is 30 seconds or more. The difference between the thickness of the molybdenum film 100 before the oxidation process and the thickness of the molybdenum film 100 after the etching process is defined as the recess amount. Depending on the oxidation conditions, the recess amount when the oxidation process and etching process are performed once each is less than several tens of nm, for example, less than 10 nm. The above values ​​are examples and are not limited to these.

[0046] If the oxidation conditions are constant, the thickness of the molybdenum oxide film 105 increases as the oxidation time increases. If the oxidation conditions are constant, even if the oxidation time exceeds the maximum growth time, the thickness of the molybdenum oxide film 105 does not change or hardly changes, remaining at or near the maximum thickness. In other words, if the oxidation conditions are constant, when the oxidation time reaches the maximum growth time, the thickness of the molybdenum oxide film 105 reaches its maximum thickness, but even if the oxidation process is continued for a longer time, the thickness of the molybdenum oxide film 105 does not change or hardly changes. This phenomenon is sometimes called self-limitation.

[0047] The maximum thickness of the molybdenum oxide film 105 depends on the oxidation conditions. The maximum growth time also depends on the oxidation conditions. When the oxidation conditions change, the maximum thickness of the molybdenum oxide film 105 increases or decreases accordingly. For example, when the temperature of the substrate W decreases, the maximum thickness of the molybdenum oxide film 105 decreases. The maximum thickness of the molybdenum oxide film 105 also decreases when the concentration or flow rate of ozone gas supplied to the substrate W decreases.

[0048] After the oxidation process, an etching process is performed to remove the molybdenum oxide film 105 from the substrate W by supplying an etching solution to the substrate W, as shown in Figure 1C. Figure 1C shows an example in which the entire molybdenum oxide film 105 is removed by supplying the etching solution, and the flat surface 103 of the molybdenum film 100 formed of molybdenum is exposed. It is preferable that the entire molybdenum oxide film 105 is removed from the substrate W by supplying the etching solution, but some of the molybdenum oxide film 105 may remain on the substrate W as long as it does not cause problems in subsequent processes.

[0049] An etching solution is a liquid that dissolves molybdenum trioxide but does not dissolve or dissolves very little molybdenum. Molybdenum trioxide dissolves in water, while molybdenum does not dissolve or dissolves very little in water. In other words, the rate at which molybdenum trioxide dissolves in water is greater than the rate at which molybdenum dissolves in water. Therefore, the etching solution can be any liquid that contains water. For example, the etching solution may be water such as pure water (deionized water: DIW), or it may be an aqueous solution of ammonium hydroxide, an alkaline solution, carbonated water, hydrofluoric acid, or hydrochloric acid. The proportion of water in the aqueous solution (the ratio of water to solute) may be 100 or more, or less than 100.

[0050] When the etching solution comes into contact with the surface 106 of the molybdenum oxide film 105, the molybdenum trioxide constituting the surface 106 of the molybdenum oxide film 105 dissolves in the etching solution, and the molybdenum oxide film 105 gradually decreases. When the etching time, that is, the time the etching solution is in contact with the molybdenum oxide film 105, reaches the etching completion time, all or almost all of the molybdenum oxide film 105 dissolves in the etching solution. The etching solution is a liquid that dissolves molybdenum trioxide but does not dissolve or hardly dissolves molybdenum. Therefore, even if the supply of the etching solution is continued beyond the etching completion time, the molybdenum film 100 will not decrease or will hardly decrease.

[0051] When performing the etching process, the etching solution may be supplied to the substrate W continuously for a period longer than the etching completion time, or the etching solution may be supplied to the substrate W intermittently so that the cumulative etching time, which represents the total time the etching solution is in contact with the molybdenum oxide film 105, is equal to or greater than the etching completion time. Furthermore, when performing the etching process, the orientation of the substrate W may be horizontal, vertical, or inclined with respect to the horizontal plane. Figure 1B shows an example of performing the etching process while maintaining the substrate W horizontally.

[0052] If, after the surface layer 102 of the molybdenum film 100 is transformed into a molybdenum oxide film 105, and then the molybdenum oxide film 105 is not etched with an etching solution, but rather an etching solution that corrodes molybdenum is supplied to the molybdenum film 100, the roughness of the surface 103 of the molybdenum film 100 may not be satisfactory. As mentioned above, if the surface layer 102 of the molybdenum film 100 is transformed into a molybdenum oxide film 105 and then removed, the roughness of the molybdenum film 100 after etching can be improved (reduced) compared to when the molybdenum film 100 is directly etched with an etching solution.

[0053] After removing all or almost all of the molybdenum oxide film 105 from the substrate W, a drying process is performed to dry the substrate W either briefly or completely. That is, when performing a second or subsequent oxidation process as described later, if the liquid remaining on the substrate W does not interfere with the oxidation process, the substrate W may be briefly dried before the next oxidation process so that most of the liquid is removed from the substrate W. Alternatively, the substrate W may be completely dried before the next oxidation process so that all of the liquid is removed from the substrate W. If the concentration of chemicals in the etching solution is high, the etching solution may be washed away with a rinsing solution such as pure water before drying the substrate W.

[0054] After the etching process, a second oxidation process is performed as described above, followed by a second etching process. If necessary, a third oxidation and etching process may be performed, or a fourth or subsequent oxidation and etching process may be performed. In other words, one cycle of performing the oxidation and etching processes in this order may be performed more than once. In this way, the thickness of the molybdenum film 100 can be gradually reduced. After the final etching process, the substrate W is completely dried.

[0055] As mentioned above, in the oxidation process, the surface 103 side of the molybdenum film 100 changes to molybdenum trioxide, and although the thickness of the molybdenum film 100 decreases, the molybdenum film 100 is not etched. If the thickness of the molybdenum oxide film 105 formed in each oxidation process is constant or nearly constant, the amount of etching in the oxidation process is zero, and the amount of etching in the etching process is a constant or nearly constant value greater than zero. This type of stepwise etching is also called digital etching.

[0056] Next, the substrate processing apparatus 1 will be described.

[0057] Figure 2 is a schematic plan view showing the layout of a batch-type substrate processing apparatus 1 according to the first embodiment of the present invention.

[0058] The substrate processing apparatus 1 is a batch-type apparatus that processes multiple substrates W at once. The substrate processing apparatus 1 includes a load port LP that holds carriers CA that accommodate disc-shaped substrates W such as semiconductor wafers, a processing unit 2 that processes the substrates W transported from the load port LP with processing liquids such as chemical solutions and rinsing solutions, a transport system 8 that transports the substrates W between the load port LP and the processing unit 2, and a control device 3 that controls the substrate processing apparatus 1.

[0059] The control device 3 is a computer that includes a memory 3m for storing information such as programs, and a CPU 3c (central processing unit) for controlling the substrate processing device 1 according to the program stored in memory 3m. The control device 3 controls the substrate processing device 1 to transport and process the substrate W as described below. In other words, the control device 3 is programmed to transport and process the substrate W as described below.

[0060] The transport system 8 includes a carrier transport device 9 that transports carriers CA between the load port LP and the processing unit 2 and accommodates multiple carriers CA, and a posture change robot 10 that loads and unloads multiple substrates W to and from the carriers CA held by the carrier transport device 9 and changes the posture of the substrates W between a horizontal and a vertical position. The posture change robot 10 performs a batch assembly operation to form one batch with multiple substrates W taken out from multiple carriers CA, and a batch release operation to accommodate the multiple substrates W included in one batch into multiple carriers CA.

[0061] The transport system 8 further includes a main transport robot 11 that transports multiple substrates W between the attitude changing robot 10 and the processing unit 2, and multiple sub-transport robots 12 that transport multiple substrates W between the main transport robot 11 and the processing unit 2. Figure 2 shows an example in which two sub-transport robots 12 and four processing units 2 are provided. In this example, the four processing units 2 are arranged in a straight line in the depth direction of the substrate processing apparatus 1 (the direction in which the main transport robot 11 transports the substrates W) in a plan view. One sub-transport robot 12 corresponds to two adjacent processing units 2, and the other sub-transport robot 12 corresponds to the remaining two adjacent processing units 2. The sub-transport robots 12 load and unload multiple substrates W to each of the two corresponding processing units 2.

[0062] The main transport robot 11 receives a batch of substrates W, consisting of multiple substrates (for example, 50 substrates) W, from the attitude change robot 10, and passes the received batch of substrates W to one of the sub-transport robots 12. The sub-transport robot 12 carries the batch of substrates W received from the main transport robot 11 to one of the processing units 2, and then unloads the processed batch of substrates W from the processing unit 2. After that, the main transport robot 11 receives the batch of substrates W from the sub-transport robot 12 and transports the received batch of substrates W to the attitude change robot 10.

[0063] Multiple substrates W, each with an exposed molybdenum film 100 or native molybdenum oxide film 104 as shown in Figure 1A, are transported to the load port LP while housed in a carrier CA. The processing unit 2 performs a single cycle, including the aforementioned oxidation and etching processes, multiple times on the multiple substrates W transported from the carrier CA on the load port LP. The multiple substrates W processed in the processing unit 2 are loaded into the carrier CA on the load port LP and transported from the load port LP while housed in the carrier CA. Therefore, the substrates W loaded into the substrate processing apparatus 1 via the load port LP are processed in the processing unit 2 and then transported out of the substrate processing apparatus 1 via the load port LP.

[0064] Next, we will describe the auxiliary transport robot 12.

[0065] Figure 3A is a schematic front view of the auxiliary transport robot 12. Figure 3B is a schematic left side view of the auxiliary transport robot 12. Figure 3B is a view of the auxiliary transport robot 12 horizontally in the depth direction (the direction in which the main transport robot 11 transports the substrate W) of the substrate processing apparatus 1 (see Figure 2). Figure 3A is a view of the auxiliary transport robot 12 horizontally in the width direction (the horizontal direction perpendicular to the depth direction of the substrate processing apparatus 1).

[0066] As shown in Figures 3A and 3B, the sub-transport robot 12 includes a support frame 13 that holds multiple substrates W transported by the main transport robot 11 (see Figure 2) in a vertical position. The support frame 13 is an example of a substrate holder for holding the substrates W. The support frame 13 includes multiple support bars 14 positioned below the multiple substrates W to be held. Figure 3A shows an example with three support bars 14. The number of support bars 14 may be two.

[0067] Multiple support bars 14 contact multiple substrates W, thereby holding the multiple substrates W in a vertical position so that they are spaced apart and facing each other parallel to one another. Each support bar 14 has multiple grooves that receive one of the multiple substrates W at a time. The multiple substrates W are placed on the multiple support bars 14. At this time, the outer circumference of each substrate W fits into the groove of each support bar 14, restricting its tilt relative to the multiple support bars 14. This maintains each substrate W in a vertical position.

[0068] The support frame 13 includes a plurality of support bars 14, a base plate 15 fixed to the plurality of support bars 14, and an upper plate 16 fixed to the plurality of support bars 14 via the base plate 15. The plurality of support bars 14 extend horizontally from the base plate 15. The upper plate 16 is positioned on the opposite side of the base plate 15 from the plurality of support bars 14. The upper plate 16 is positioned above the plurality of support bars 14. When the upper plate 16 is moved, the plurality of support bars 14 and the base plate 15 move in the same direction as the upper plate 16 at the same speed.

[0069] The auxiliary transport robot 12 corresponds to a lifter that holds multiple substrates W and raises and lowers the multiple substrates W. The auxiliary transport robot 12 includes a lifting actuator 17 that moves the support frame 13 vertically. The auxiliary transport robot 12 further includes a slide actuator 18 that moves the support frame 13 horizontally. Power from the lifting actuator 17 is transmitted to multiple support bars 14 via an upper plate 16 and a base plate 15. Power from the slide actuator 18 is transmitted to multiple support bars 14 via the lifting actuator 17, the upper plate 16, and the base plate 15.

[0070] When the lifting actuator 17 moves the support frame 13 vertically, the multiple substrates W supported by the support frame 13 also move vertically. As a result, the multiple substrates W supported by the support frame 13 are transported vertically. Similarly, when the slide actuator 18 moves the support frame 13 horizontally, the multiple substrates W supported by the support frame 13 also move horizontally. As a result, the multiple substrates W supported by the support frame 13 are transported horizontally.

[0071] The lifting actuator 17 is an actuator that moves the support frame 13 vertically in parallel. An actuator is a device that converts electrical, fluid, magnetic, thermal, or chemical energy into mechanical work. Actuators include electric motors, air cylinders, and other devices. The lifting actuator 17 may be an electric motor or an air cylinder, or it may be something other than these. The definition of an actuator is also similar for other actuators such as the slide actuator 18.

[0072] Next, we will describe the processing unit 2.

[0073] Figures 4A and 4B are schematic cross-sectional views showing the vertical cross-section of the processing unit 2. Figure 4A shows a vertical cross-section parallel to the multiple substrates W held by the sub-transport robot 12. Figure 4B shows a vertical cross-section perpendicular to the multiple substrates W held by the sub-transport robot 12.

[0074] As shown in Figure 4A, the processing unit 2 comprises a plurality of partitions 52 that form the internal space of the processing unit 2, including an oxidation space SO and an etching space SE. The processing unit 2 further comprises at least one heating lamp 21 for irradiating light onto a plurality of substrates W in the oxidation space SO, an ozone gas supply port 22 for supplying ozone gas to the plurality of substrates W in the oxidation space SO, and a first processing tank 41 for accumulating etching solution in the etching space SE into which the plurality of substrates W are immersed. These configurations will be described below.

[0075] First, we will explain the heating of the substrate W and the supply of ozone gas.

[0076] The processing unit 2 includes at least one heating lamp 21 that heats a plurality of substrates W in an oxidation space SO to a heating temperature by irradiating the substrates W with light. The heating lamp 21 is an example of a heater that heats a plurality of substrates W in an oxidation space SO. The heating lamp 21 may be a halogen lamp or an LED (light-emitting diode) lamp, or any other type of lamp. The heating lamp 21 includes a light source that emits light when power is supplied, and a transparent case that houses the light source.

[0077] Figures 4A and 4B show an example where four heating lamps 21 are arranged in one oxidizing space SO. The number of heating lamps 21 irradiating light onto a substrate W in a single oxidizing space SO may be less than four or more than five. The heating lamps 21 may be located outside the oxidizing space SO, as long as they can irradiate light onto the substrate W in the oxidizing space SO. When multiple substrates W are arranged in the oxidizing space SO, the light from at least one heating lamp 21 irradiates all of the substrates W in the oxidizing space SO. This heats all of the substrates W in the oxidizing space SO without contact.

[0078] As shown in Figure 4A, the processing unit 2 includes an ozone gas supply port 22 for supplying ozone gas to the oxidizing space SO. The ozone gas supply port 22 includes a space through which the ozone gas passes and an end face that forms this space (typically an annular end face surrounding the entire circumference of the space). As long as the ozone gas flowing out of the ozone gas supply port 22 is supplied to the oxidizing space SO, the ozone gas supply port 22 may open onto the wall forming the oxidizing space SO, or it may be located inside the wall. Figure 4A shows an example of the former.

[0079] The processing unit 2 includes, in addition to the ozone gas supply port 22, an ozone gas generator 25 that generates ozone gas to be supplied to the ozone gas supply port 22, an ozone gas piping 23 that guides the ozone gas generated by the ozone gas generator 25 toward the ozone gas supply port 22, and an ozone gas valve 24 that opens and closes between an open state in which ozone gas flows from the ozone gas piping 23 to the ozone gas supply port 22 and a closed state in which ozone gas does not flow from the ozone gas piping 23 to the ozone gas supply port 22.

[0080] Although not shown in the figures, the ozone gas valve 24 includes a valve body provided with an internal flow path through which fluid flows and an annular valve seat that forms part of the internal flow path, a valve element movable relative to the valve seat, and an actuator that moves the valve element between a closed position where the valve element is in contact with the valve seat and an open position where the valve element is away from the valve seat. The same applies to other valves. The actuator may be a pneumatic actuator or an electric actuator, or any other type of actuator. The control device 3 (see Figure 2) opens and closes the ozone gas valve 24 by controlling the actuator.

[0081] The processing unit 2 further includes a first exhaust port 28 for discharging gas from the oxidizing space SO, a first exhaust pipe 29 for guiding the gas flowing into the first exhaust port 28 away from the oxidizing space SO, and a first exhaust valve 30 that opens and closes between an open state in which gas from the oxidizing space SO flows into the first exhaust port 28 and a closed state in which gas from the oxidizing space SO does not flow into the first exhaust port 28. The first exhaust port 28 includes a space through which the gas to be discharged passes and an end face that forms this space. As long as the first exhaust port 28 can discharge gas from the oxidizing space SO, the first exhaust port 28 may open onto the wall surface forming the oxidizing space SO, or it may be located inside the wall surface.

[0082] When the ozone gas valve 24 is opened, ozone gas flows out from the ozone gas supply port 22 and is supplied to the oxidizing space SO. If the supply of ozone gas continues with the first exhaust valve 30 open, the oxidizing space SO will be filled with ozone gas. The filling of the oxidizing space SO with ozone gas may be carried out by supplying ozone gas to the oxidizing space SO while discharging the gas in the oxidizing space SO to the first exhaust port 28, or by discharging the gas in the oxidizing space SO to the first exhaust port 28 and then supplying ozone gas to the oxidizing space SO.

[0083] After the oxidizing space SO is filled with ozone gas, the supply of ozone gas from the ozone gas supply port 22 and the discharge of gas to the first exhaust port 28 may be continued or stopped. In the former case, while filling the oxidizing space SO with ozone gas, the atmospheric pressure inside the oxidizing space SO may be maintained at a value equal to or less than the atmospheric pressure outside the oxidizing space SO. In this case, the first exhaust valve 30 may be a relief valve that, when the atmospheric pressure inside the oxidizing space SO rises above a set value, allows gas inside the oxidizing space SO to flow into the first exhaust port 28 until the atmospheric pressure drops below a set value. The first exhaust valve 30 may include both an on / off valve and a relief valve.

[0084] The processing unit 2 includes a first inert gas pipe 26 that guides nitrogen gas, which is an example of an inert gas to be supplied to the oxidizing space SO, and a first inert gas valve 27 that opens and closes between an open state in which nitrogen gas flows from the first inert gas pipe 26 to the oxidizing space SO and a closed state in which nitrogen gas does not flow from the first inert gas pipe 26 to the oxidizing space SO. Figure 4A shows an example in which nitrogen gas in the first inert gas pipe 26 is supplied to the oxidizing space SO via an ozone gas supply port 22. The nitrogen gas in the first inert gas pipe 26 may also be supplied to the oxidizing space SO via a supply port other than the ozone gas supply port 22.

[0085] After supplying ozone gas to the oxidizing space SO, the ozone gas in the oxidizing space SO is discharged through the first exhaust port 28. Specifically, after supplying ozone gas to the oxidizing space SO, the ozone gas valve 24 is closed, and with the first exhaust valve 30 open, the first inert gas valve 27 is opened. As a result, nitrogen gas is supplied to the oxidizing space SO, and gases in the oxidizing space SO, such as ozone gas, are discharged through the first exhaust port 28. Consequently, the ozone gas in the oxidizing space SO is replaced by nitrogen gas, and the oxidizing space SO is filled with nitrogen gas.

[0086] The processing unit 2 includes a vapor supply port 31 that supplies vapor of an organic solvent, which is more volatile than water and soluble in water, to the oxidation space SO. The vapor supply port 31 includes a space through which the organic solvent vapor passes and an end face that forms this space. As long as the organic solvent vapor flowing out of the vapor supply port 31 is supplied to the oxidation space SO, the vapor supply port 31 may open onto the wall surface forming the oxidation space SO, or it may be located inside the wall surface.

[0087] The processing unit 2 includes, in addition to the steam supply port 31, a steam generator 34 that generates vapor of the organic solvent to be supplied to the steam supply port 31, a steam pipe 32 that guides the vapor of the organic solvent generated by the steam generator 34 toward the steam supply port 31, and a steam valve 33 that opens and closes between an open state in which the vapor of the organic solvent flows from the steam pipe 32 to the steam supply port 31 and a closed state in which the vapor of the organic solvent does not flow from the steam pipe 32 to the steam supply port 31. Figure 4A shows an example in which the vapor of the organic solvent is IPA (isopropyl alcohol). IPA is an example of an alcohol that contains hydrophilic and hydrophobic groups in its chemical formula.

[0088] When the steam valve 33 is opened, IPA vapor flows out from the steam supply port 31 and is supplied to the oxidizing space SO. If the supply of IPA vapor continues with the first exhaust valve 30 open, the oxidizing space SO will be filled with IPA vapor. The filling of the oxidizing space SO with IPA vapor may be carried out by supplying IPA vapor to the oxidizing space SO while discharging the gas in the oxidizing space SO to the first exhaust port 28, or by discharging the gas in the oxidizing space SO to the first exhaust port 28 and then supplying IPA vapor to the oxidizing space SO.

[0089] After the oxidizing space SO is filled with IPA vapor, the supply of IPA vapor from the vapor supply port 31 and the discharge of gas to the first exhaust port 28 may be continued or stopped. In the former case, while filling the oxidizing space SO with IPA vapor, the atmospheric pressure inside the oxidizing space SO may be maintained at a value equal to or less than the atmospheric pressure outside the oxidizing space SO. In this case, the first exhaust valve 30 may be a relief valve that, when the atmospheric pressure inside the oxidizing space SO rises above a set value, allows gas inside the oxidizing space SO to flow into the first exhaust port 28 until the atmospheric pressure drops below a set value. The first exhaust valve 30 may include both an on / off valve and a relief valve.

[0090] When IPA vapor fills the oxidizing space SO, and a liquid such as pure water is adhering to the substrate W within the oxidizing space SO, the IPA vapor comes into contact with the substrate W, and the liquid adhering to the substrate W is replaced by the liquid IPA. The liquid IPA adhering to the substrate W evaporates and disappears from the substrate W. As a result, the liquid adhering to the substrate W is removed, and the substrate W dries in the oxidizing space SO, which also serves as a drying space.

[0091] The processing unit 2 includes a second inert gas pipe 35 that guides nitrogen gas, which is an example of an inert gas to be supplied to the oxidizing space SO, and a second inert gas valve 36 that opens and closes between an open state in which nitrogen gas flows from the second inert gas pipe 35 to the oxidizing space SO and a closed state in which nitrogen gas does not flow from the second inert gas pipe 35 to the oxidizing space SO. Figure 4A shows an example in which nitrogen gas in the second inert gas pipe 35 is supplied to the oxidizing space SO via a steam supply port 31. The nitrogen gas in the second inert gas pipe 35 may also be supplied to the oxidizing space SO via a supply port other than the ozone gas supply port 22 and the steam supply port 31.

[0092] After supplying IPA vapor to the oxidizing space SO, the IPA vapor in the oxidizing space SO is discharged through the first exhaust port 28. Specifically, after supplying IPA vapor to the oxidizing space SO, the vapor valve 33 is closed, and with the first exhaust valve 30 open, the second inert gas valve 36 is opened. This supplies nitrogen gas to the oxidizing space SO, and gases in the oxidizing space SO, such as IPA vapor, are discharged through the first exhaust port 28. As a result, the IPA vapor in the oxidizing space SO is replaced with nitrogen gas, and the oxidizing space SO is filled with nitrogen gas.

[0093] Next, we will explain the supply of the etching solution.

[0094] The processing unit 2 includes a first processing tank 41 that stores etching solution in an etching space SE into which multiple substrates W are immersed. The first processing tank 41 corresponds to an etching processing tank that stores etching solution. Figure 4A shows an example where the etching solution is pure water (indicated as DIW in Figure 4A). The first processing tank 41 includes an inner tank 42 for storing etching solution and an outer tank 43 for storing etching solution that overflows from the inner tank 42. The inner tank 42 includes a cylindrical outer wall and a bottom wall that closes the bottom of the outer wall. Multiple substrates W are placed into the inner tank 42 from the top and immersed in the etching solution inside the inner tank 42. As a result, multiple substrates W come into contact with the etching solution, and the etching solution is supplied to each substrate W.

[0095] The processing unit 2 is equipped with a circulation system for circulating the etching solution in the first processing tank 41. The circulation system includes a circulation pipe 44 that guides the etching solution in the outer tank 43 toward the inner tank 42, and a return nozzle 47 that supplies the etching solution into the inner tank 42 by discharging the etching solution supplied from the circulation pipe 44 through a discharge port 47p located in the inner tank 42. Figure 4A shows an example in which two return nozzles 47 are provided. In this example, the circulation pipe 44 includes an upstream pipe 44u extending downstream from the outer tank 43, and two downstream pipes 44d branching off from the upstream pipe 44u.

[0096] The circulation system further includes a circulation pump 46 that sends the etching solution in the circulation pipe 44 toward the inner tank 42, and a filter 45 that removes foreign matter from the etching solution flowing through the circulation pipe 44. The circulation pump 46 constantly sends the etching solution from the upstream end of the circulation pipe 44 toward the downstream end of the circulation pipe 44. The etching solution continuously overflows from the inner tank 42 into the outer tank 43 and circulates through the circulation path formed by the inner tank 42, the outer tank 43, the circulation pipe 44, and the return nozzle 47. If the etching solution in the first processing tank 41 is to be maintained at a temperature higher or lower than room temperature, the etching solution flowing through the circulation pipe 44 may be heated or cooled by a heater or cooler.

[0097] Next, we will explain the oxidation space SO and the etching space SE.

[0098] The processing unit 2 comprises a plurality of partitions 52 that form the internal space of the processing unit 2, including an oxidation space SO and an etching space SE. The partition 52 may be a single plate, or it may be a plurality of plates arranged on a single plane and connected to one another. The partition 52 may be square or rectangular, or it may have any other shape. If the partition 52 includes a plurality of plates, all plates may be the same shape, or the partition 52 may contain a plurality of plates with different shapes. The same applies to the size and material of each plate when the partition 52 includes a plurality of plates.

[0099] Multiple partitions 52 surround the entire perimeter of the oxidation space SO and are located above and below the oxidation space SO. Similarly, multiple partitions 52 surround the entire perimeter of the etching space SE and are located above and below the etching space SE. The oxidation space SO and the etching space SE are separated by a first inner partition 57, which will be described later. The oxidation space SO is positioned above the etching space SE so as to overlap it in a plan view.

[0100] As shown in Figure 4B, the multiple partitions 52 are arranged inside the outer wall 51 of the substrate processing apparatus 1, which forms the outer surface of the substrate processing apparatus 1. The multiple partitions 52 include at least one fixed partition 53 fixed to the outer wall 51 of the substrate processing apparatus 1, and a plurality of movable partitions that are movable relative to the outer wall 51 of the substrate processing apparatus 1. The plurality of movable partitions include an outer partition 55 that forms the contour of the internal space of the processing unit 2, and a first inner partition 57 that divides the internal space of the processing unit 2.

[0101] Multiple partitions 52 form entrances and exits 54 through which multiple substrates W pass in and out of the internal space of the processing unit 2. Figures 4A and 4B show an example in which a fixed partition 53 located above the oxidation space SO forms the entrances and exits 54. The entrances and exits 54 may also be formed by fixed partitions 53 located around the oxidation space SO. The entrances and exits 54 may also be formed by fixed partitions 53 other than the fixed partitions 53 that form the oxidation space SO.

[0102] The entrance / exit 54 is opened and closed by an outer partition 55 which acts as a shutter. An opening / closing actuator 56 moves the outer partition 55 between an open position, which allows multiple substrates W to pass through the entrance / exit 54, and a closed position, which closes the entrance / exit 54 by the outer partition 55. The outer partition 55 may be a sliding type that moves parallel between the open and closed positions, or a rotating type that rotates between the open and closed positions, or it may be of any other type. When the opening / closing actuator 56 moves the outer partition 55 to the closed position, the entrance / exit 54 is sealed by the outer partition 55.

[0103] The internal space of the processing unit 2 is divided into an oxidation space SO and an etching space SE by a first inner partition 57. The first inner partition 57 is positioned between the oxidation space SO and the etching space SE, separating them. The contour of the oxidation space SO is formed by the outer partition 55, the first inner partition 57, and the fixed partition 53. The contour of the etching space SE is formed by the first inner partition 57 and the fixed partition 53.

[0104] The traffic switching actuator 58 moves the first inner partition 57 between an open position in which multiple substrates W can move between the oxidation space SO and the etching space SE, and a closed position in which the movement of the substrates W between the oxidation space SO and the etching space SE is blocked by the first inner partition 57. The first inner partition 57 may be a sliding type that moves parallel between the open position and the closed position, or a rotating type that rotates between the open position and the closed position, or it may be of any other form. When the traffic switching actuator 58 moves the first inner partition 57 to the closed position, the oxidation space SO and the etching space SE are separated by the first inner partition 57 so that fluids such as liquids and gases cannot move between the oxidation space SO and the etching space SE.

[0105] The two white arrows in Figure 4B indicate that the outer partition 55 moves in the width direction (left-right direction in Figure 4B) of the substrate processing apparatus 1 between the open and closed positions, and that the first inner partition 57 moves in the width direction of the substrate processing apparatus 1 between the open and closed positions. The outer partition 55 may also be able to move in a direction different from the width direction of the substrate processing apparatus 1. The same applies to the first inner partition 57.

[0106] Multiple partitions 52 house a heating lamp 21 and a first processing tank 41. The heating lamp 21 is located in the oxidation space SO. The first processing tank 41 is located in the etching space SE. In the examples shown in Figures 4A and 4B, the first inner partition 57 is located above the first processing tank 41, and the outer partition 55 is located above the first inner partition 57. When the outer partition 55 and the first inner partition 57 are in their respective closed positions, the outer partition 55 overlaps the first inner partition 57 in a plan view. The vertical distance from the surface of the etching solution in the inner tank 42 to the bottom surface of the first inner partition 57 is less than the diameter of the substrate W. This distance may be greater than or equal to the diameter of the substrate W.

[0107] The oxidation space SO and the etching space SE are spaces formed inside the substrate processing apparatus 1. When the outer partition 55 and the first inner partition 57 are positioned in their respective closed positions, the oxidation space SO is sealed. In other words, fluid cannot enter or exit the oxidation space SO except through specific locations such as the ozone gas supply port 22, the steam supply port 31, and the first exhaust port 28. When the first inner partition 57 is in the closed position, the etching space SE may be a sealed space similar to the oxidation space SO, or it may be an open space from which fluid can freely enter and exit.

[0108] The auxiliary transport robot 12 loads and unloads multiple substrates W into and out of the internal space of the processing unit 2. The auxiliary transport robot 12 further moves the multiple substrates W within the internal space of the processing unit 2 and stops them at any position within the internal space of the processing unit 2. In the example shown in Figures 4A and 4B, the auxiliary transport robot 12 moves the multiple substrates W between the oxidation space SO and the etching space SE, and stops the multiple substrates W in both the oxidation space SO and the etching space SE.

[0109] As described above, the sub-transport robot 12 includes a plurality of support bars 14, a base plate 15, and an upper plate 16. The plurality of support bars 14 are positioned in the internal space of the processing unit 2, which includes an oxidation space SO and an etching space SE, while supporting a plurality of substrates W. At this time, the base plate 15 is also positioned in the internal space of the processing unit 2. The upper plate 16 is inserted into a guide groove 59 that penetrates at least one partition 52. Therefore, a portion of the upper plate 16 is positioned in the internal space of the processing unit 2, and the remaining portion of the upper plate 16 is positioned outside the internal space of the processing unit 2.

[0110] The guide groove 59 opens on the inner and outer surfaces of at least one partition 52. The guide groove 59 connects the space outside the multiple partitions 52 to the internal space of the processing unit 2. The upper plate 16 moves together with the multiple support bars 14 and base plate 15 while inserted into the guide groove 59. When a portion of the upper plate 16 is stationary in the guide groove 59, and when it is moving within the guide groove 59, the gap between the surface of the upper plate 16 and the inner surface of the guide groove 59 is sealed. This maintains a sealed state between the upper plate 16 and the guide groove 59.

[0111] Next, we will describe an example of the processing of substrate W.

[0112] Figure 5 is a process diagram illustrating an example of processing of substrate W according to the first embodiment of the present invention. Figures 6A, 6B, 6C, 6D, 6E, 6F, and 6G are schematic cross-sectional views showing the state of processing unit 2 when the example of processing of substrate W shown in Figure 5 is being performed. Hereafter, Figures 4A, 4B, and 5 will be referred to. Figures 6A to 6G will be referred to as appropriate.

[0113] When processing substrates W in processing unit 2, the main transport robot 11 (see Figure 2) passes multiple substrates W constituting one batch to the sub-transport robot 12. Then, the opening / closing actuator 56 moves the outer partition 55, which corresponds to the shutter of processing unit 2, from the closed position to the open position, opening the entrance / exit 54 of processing unit 2. Subsequently, as shown in Figure 6A, the sub-transport robot 12 moves the multiple support bars 14 into processing unit 2 through the entrance / exit 54, supporting one batch of substrates W with the support bars 14. As a result, multiple substrates W are brought into processing unit 2 (step S1 in Figure 5).

[0114] After multiple substrates W have been brought in, with the first inner partition 57 in the closed position, the opening / closing actuator 56 moves the outer partition 55 from the open position to the closed position. This seals the oxidation space SO. Subsequently, ozone gas is filled into the oxidation space SO. The heating lamp 21 is started to emit light either before or after the oxidation space SO is filled with ozone gas. Then, as shown in Figure 6B, the oxidation process is carried out continuously for longer than the aforementioned maximum growth time while maintaining constant conditions such as the temperature of the substrate W and the concentration of ozone gas in the atmosphere in contact with the substrate W (step S2 in Figure 5).

[0115] During the oxidation process, oxygen atoms in the atmosphere in contact with the substrate W combine with molybdenum in the molybdenum film 100 (see Figure 1B), and the molybdenum is converted to molybdenum trioxide. As a result, a molybdenum oxide film 105 (see Figure 1B) containing molybdenum trioxide is formed on the surface 103 of the molybdenum film 100. Furthermore, if the oxidation process is carried out continuously for more than the maximum growth time while maintaining constant oxidation conditions, the thickness of the molybdenum oxide film 105 increases to its maximum thickness due to the aforementioned self-limitation and remains at that maximum thickness.

[0116] After the oxidation process has been performed continuously for longer than the maximum growth time, the heating lamp 21 is stopped emitting light. Before or after the heating lamp 21 stops emitting light, gases in the oxidation space SO, such as ozone gas, are discharged through the first exhaust port 28, and gases other than ozone gas, such as inert gas, are filled into the oxidation space SO. After the heating lamp 21 stops emitting light and the ozone gas in the oxidation space SO is discharged, the passage switching actuator 58 moves the first inner partition 57 from the closed position to the open position. As a result, the processing unit 2 switches from a movement-prohibited state, where multiple substrates W cannot move between the oxidation space SO and the etching space SE, to a movement-permitted state, where multiple substrates W can move between the oxidation space SO and the etching space SE.

[0117] After the first inner partition 57 moves to the open position, as shown in Figure 6C, the sub-transport robot 12 moves the multiple support bars 14 to move the multiple substrates W supported by the multiple support bars 14 toward the etching space SE until the entire substrates W are immersed in the etching solution in the first processing tank 41 (step S3 in Figure 5). As a result, the multiple substrates W supported by the multiple support bars 14 move toward the etching space SE, and the etching solution is supplied to the entire outer surface of each substrate W. After the multiple substrates W have moved toward the etching space SE, the passage switching actuator 58 may move the first inner partition 57 to the closed position or leave it stationary in the open position. Figure 6D shows an example of the former.

[0118] As shown in Figure 6D, the sub-transport robot 12 maintains that the entirety of the multiple substrates W supported by the multiple support bars 14 are immersed in the etching solution in the first processing tank 41 for longer than the etching completion time mentioned above. As a result, all or almost all of the molybdenum oxide film 105 is removed from the substrates W, and the remaining portion of the molybdenum film 100 that did not change into molybdenum trioxide remains on the substrates W (step S4 in Figure 5). In other words, the thickness of the molybdenum film 100 decreases compared to before the oxidation process because a portion of the molybdenum film 100 changes into molybdenum trioxide, and the molybdenum oxide film 105 formed by the oxidation of the molybdenum film 100 is removed from the molybdenum film 100 by the supply of etching solution.

[0119] After supplying etching solution to multiple substrates W for more than the etching completion time, as shown in Figure 6E, the sub-transport robot 12 moves the multiple support bars 14 to move the multiple substrates W supported by the multiple support bars 14 from the etching space SE to the oxidation space SO (step S5 in Figure 5). If the first inner partition 57 is in the closed position, the first inner partition 57 is moved to the open position before moving the multiple substrates W out of the etching space SE, and the first inner partition 57 is moved to the closed position after the multiple substrates W have moved to the oxidation space SO.

[0120] After the multiple substrates W have moved to the oxidation space SO, an oxidation process is performed in which the multiple substrates W in the oxidation space SO are heated while ozone gas is supplied to the multiple substrates W in the oxidation space SO, as described above (step S6 in Figure 5). After the second oxidation process, an etching process is performed in which the multiple substrates W are immersed in the etching solution in the etching space SE, as described above (step S6 in Figure 5). A third oxidation and etching process may be performed as needed, or a fourth or subsequent oxidation and etching process may be performed. In Figure 5, "N" is a positive integer.

[0121] After the etching process and before the oxidation process, a drying process may be performed to dry the substrate W simply or completely. That is, the oxidation space SO may be filled with IPA vapor supplied from the vapor supply port 31, or a gas such as an inert gas may be blown onto multiple substrates W. When the sub-transport robot 12 moves the multiple substrates W out of the first processing tank 41, most of the etching solution flows out of the substrates W. Therefore, if the small amount of etching solution remaining on the substrates W does not substantially affect the oxidation process, the oxidation process may be performed without drying the substrates W.

[0122] After the final etching process, the sub-transport robot 12 moves the multiple support bars 14 to move the multiple substrates W from the etching space SE to the oxidation space SO, and the passage switching actuator 58 moves the first inner partition 57 to the closed position. Then, as shown in Figure 6F, a drying process is performed in which IPA vapor is filled into the oxidation space SO (step S7 in Figure 5). This removes any liquid adhering to the substrates W, and the multiple substrates W supported by the multiple support bars 14 are dried in the oxidation space SO, which also serves as the drying space. After that, the IPA vapor is discharged from the oxidation space SO through the first exhaust port 28, and the oxidation space SO is filled with a gas such as an inert gas.

[0123] After the multiple substrates W in the oxidizing space SO have dried, the opening / closing actuator 56 moves the outer partition 55 from the closed position to the open position, and as shown in Figure 6G, the sub-transport robot 12 moves the multiple support bars 14 to move the multiple substrates W out of the processing unit 2 through the entrance / exit 54 (step S8 in Figure 5). The sub-transport robot 12 then passes the multiple substrates W to the main transport robot 11 (see Figure 2). The multiple substrates W passed to the main transport robot 11 are placed in the carrier CA (see Figure 2) on the load port LP. In this way, the multiple unprocessed substrates W are brought into the processing unit 2, and the multiple processed substrates W are discharged from the processing unit 2.

[0124] As described above, in this embodiment, with multiple substrates W placed in the oxidation space SO within the substrate processing apparatus 1, the multiple substrates W are heated while oxygen gas or ozone gas is supplied to the multiple substrates W. As a result, oxygen atoms contained in the oxygen gas or ozone gas combine with molybdenum, and the surface layer 102 of the molybdenum film 100 changes to molybdenum trioxide. Subsequently, the multiple substrates W are transported from the oxidation space SO within the substrate processing apparatus 1 to the etching space SE within the substrate processing apparatus 1, and etching solution is supplied to the multiple substrates W in the etching space SE. The molybdenum trioxide dissolves in the etching solution. Therefore, the surface layer 102 of the molybdenum film 100 that has changed to molybdenum trioxide is etched, and the parts of the molybdenum film 100 other than the surface layer 102 that have not changed to molybdenum trioxide remain on the substrate W.

[0125] In this way, by heating the substrate W while supplying oxygen gas or ozone gas to the substrate W, the molybdenum film 100 formed on the substrate W can be oxidized. Furthermore, since the molybdenum film 100 is oxidized and etched within a single substrate processing apparatus 1, the time required for transporting the substrate W can be reduced compared to when the oxidation of the molybdenum film 100 and the etching of the molybdenum oxide film 105 are performed in separate substrate processing apparatuses. In addition, since multiple substrates W are oxidized and etched together, the time required for oxidation and etching can be reduced compared to when multiple substrates W are oxidized one by one and etched one by one.

[0126] In this embodiment, the substrate W is heated while ozone gas is supplied to the substrate W instead of oxygen gas. Therefore, compared to the case where oxygen gas is supplied to the substrate W while heating, the surface layer 102 of the molybdenum film 100 can be efficiently converted to molybdenum trioxide. This shortens the time required to convert the surface layer 102 of the molybdenum film 100 to molybdenum trioxide, and increases the throughput of the substrate processing apparatus 1 (the number of substrates W processed per unit time).

[0127] In this embodiment, a water-containing solution, mainly composed of water, is supplied to the substrate W for etching. Molybdenum trioxide dissolves in water, while molybdenum does not dissolve or hardly dissolves in water. Therefore, the surface layer 102 of the molybdenum film 100, which has been converted to molybdenum trioxide, can be removed from the substrate W without using chemicals. This simplifies the treatment of wastewater and reduces the environmental burden compared to when the etching solution is a chemical.

[0128] In this embodiment, after supplying etching solution to multiple substrates W in the etching space SE, the multiple substrates W are transported to the oxidation space SO, and the multiple molybdenum films 100 formed on the multiple substrates W are oxidized. In other words, the oxidation of the molybdenum film 100 and the etching of the molybdenum oxide film 105 are repeated alternately multiple times. This makes it possible to gradually reduce the thickness of the molybdenum film 100 and to adjust the thickness of the molybdenum film 100 in stages.

[0129] In this embodiment, multiple substrates W are held in a support frame 13, which is an example of a substrate holder, while multiple molybdenum films 100 are oxidized, the multiple substrates W are transported from the oxidation space SO to the etching space SE, and the multiple molybdenum oxide films 105 are etched. In other words, in order to oxidize the molybdenum films 100, transport the substrates W from the oxidation space SO to the etching space SE, and etch the molybdenum oxide films 105, it is not necessary to move the multiple substrates W held in the substrate holder to another substrate holder, nor is it necessary to provide multiple substrate holders. This makes it possible to increase the throughput of the substrate processing apparatus 1.

[0130] In this embodiment, the first inner partition 57 is positioned between the oxidation space SO and the etching space SE, forming part of the contour of the oxidation space SO and part of the contour of the etching space SE. At least a portion of the oxidation space SO is separated from the etching space SE only by the first inner partition 57. Moving the first inner partition 57 allows multiple substrates W to move between the oxidation space SO and the etching space SE. Since the oxidation space SO is positioned near the etching space SE only through the first inner partition 57, the time required to transport the substrates W to the etching space SE can be reduced, and the throughput of the substrate processing apparatus 1 can be increased.

[0131] In this embodiment, after supplying etching solution to multiple substrates W, the multiple substrates W are moved from the etching space SE to the oxidation space SO. Subsequently, the multiple substrates W are dried in the oxidation space SO. In other words, the oxidation space SO also serves as a drying space for the substrates W, and oxidation and drying of the molybdenum film 100 occur on the substrates W within the oxidation space SO. Therefore, the substrate processing apparatus 1 can be miniaturized compared to the case where a separate drying space is provided from the oxidation space SO.

[0132] Next, a second embodiment will be described.

[0133] In Figures 7 to 8C below, configurations equivalent to those shown in Figures 1A to 6G above are given the same reference numerals as in Figure 1A, etc., and their descriptions are omitted.

[0134] The main difference between the second embodiment and the first embodiment is that in the first embodiment, the oxidation space SO also serves as the drying space, whereas in the second embodiment, the drying space SD is a separate space from the oxidation space SO.

[0135] Figure 7 is a schematic cross-sectional view showing a vertical cross-section of a processing unit 2 according to a second embodiment of the present invention. As shown in Figure 7, the plurality of movable partitions include an outer partition 55 and a first inner partition 57, as well as a second inner partition 61 located between the oxidation space SO and the drying space SD. The contour of the drying space SD is formed by the second inner partition 61 and at least one fixed partition 53.

[0136] Figure 7 shows an example where the drying space SD is positioned to the side of the oxidizing space SO. Alternatively, the drying space SD may be positioned above the oxidizing space SO so that it overlaps with the oxidizing space SO in a plan view. In this case, an inlet / outlet 54 should be formed in the fixed partition 53 that forms the drying space SD. The drying space SD may also be positioned between the oxidizing space SO and the etching space SE. In this case, the drying space SD and the etching space SE should be separated by the first inner partition 57.

[0137] Figure 7 shows an example in which an inlet / outlet 54 formed in a partition 52 that partitions the oxidation space SO is opened and closed by an outer partition 55. Alternatively, an inlet / outlet 54 may be formed in a partition 52 that partitions the drying space SD, and this inlet / outlet 54 may be opened and closed by an outer partition 55. In this case, an inlet / outlet 54 may be formed only in the partition 52 that partitions the drying space SD, or one inlet / outlet 54 may be formed in both the partition 52 that partitions the drying space SD and the partition 52 that partitions the oxidation space SO. In other words, two inlets / outlets 54 may be provided in one processing unit 2. In this case, one inlet / outlet 54 may be dedicated to the inlet and the other inlet / outlet 54 may be dedicated to the outlet.

[0138] The passage switching actuator 62 moves the second inner partition 61 between an open position in which multiple substrates W can move between the oxidation space SO and the drying space SD, and a closed position in which the movement of the substrates W between the oxidation space SO and the drying space SD is blocked by the second inner partition 61. The second inner partition 61 may be a sliding type that moves parallel between the open position and the closed position, or a rotating type that rotates between the open position and the closed position, or it may be of any other type.

[0139] When the flow switching actuator 62 moves the second inner partition 61 to the closed position, the oxidation space SO and the dry space SD are separated by the second inner partition 61 so that fluids such as liquids and gases cannot move between them. The IPA vapor flowing out from the steam supply port 31 is supplied to the dry space SD, not to the oxidation space SO. When the second inner partition 61 is in the closed position, the dry space SD is sealed, and fluids cannot enter or leave the dry space SD except through specific locations such as the steam supply port 31.

[0140] The processing unit 2 includes a first exhaust port 28 for discharging gas in the oxidizing space SO, as well as a second exhaust port 63 for discharging gas in the drying space SD. The processing unit 2 further includes a second exhaust pipe 64 that guides the gas flowing into the second exhaust port 63 away from the drying space SD, and a second exhaust valve 65 that opens and closes between an open state in which gas in the drying space SD flows into the second exhaust port 63 and a closed state in which gas in the drying space SD does not flow into the second exhaust port 63. By supplying IPA vapor from the vapor supply port 31 to the drying space SD and discharging the gas in the drying space SD to the second exhaust port 63, the drying space SD can be filled with IPA vapor.

[0141] Figures 8A, 8B, and 8C are schematic cross-sectional views showing the state of the processing unit 2 when an example of processing of the substrate W according to the second embodiment of the present invention is being performed. Figure 7 will be referenced below. Figures 8A to 8C will be referenced as appropriate.

[0142] When processing multiple substrates W with the processing unit 2 according to the second embodiment, the multiple substrates W are moved between the oxidation space SO and the etching space SE, similar to the processing unit 2 according to the first embodiment, thereby performing one cycle including the oxidation process and the etching process multiple times.

[0143] After the final etching process, the passage switching actuator 62 moves the second inner partition 61 from the closed position to the open position, thereby switching the processing unit 2 from a movement-prohibited state where multiple substrates W cannot move between the oxidation space SO and the drying space SD, to a movement-permitted state where multiple substrates W can move between the oxidation space SO and the drying space SD. In this state, as shown in Figure 8A, the sub-transport robot 12 moves multiple support bars 14 to move the multiple substrates W from the etching space SE through the oxidation space SO to the drying space SD.

[0144] After the multiple substrates W have moved from the oxidation space SO to the drying space SD, the passage switching actuator 62 moves the second inner partition 61 from the open position to the closed position. Then, as shown in Figure 8B, a drying process is performed in which IPA vapor supplied from the vapor supply port 31 fills the drying space SD. This removes any liquid adhering to the substrates W and dries the multiple substrates W supported by the multiple support bars 14 within the drying space SD. After that, the IPA vapor is discharged from the drying space SD through the second exhaust port 63, and the drying space SD is filled with a gas such as an inert gas.

[0145] After the multiple substrates W in the drying space SD have dried, the passage switching actuator 62 moves the second inner partition 61 from the closed position to the open position, and as shown in Figure 8C, the sub-transport robot 12 moves the multiple substrates W from the drying space SD to the oxidation space SO. Subsequently, the opening / closing actuator 56 moves the outer partition 55 from the closed position to the open position, and as shown in Figure 8C, the sub-transport robot 12 moves the multiple substrates W outside the processing unit 2 through the entrance / exit 54.

[0146] In the second embodiment, in addition to the effects of the first embodiment, the following effects can be achieved. Specifically, in the second embodiment, the second inner partition 61 is positioned between the oxidation space SO or etching space SE and the drying space SD. At least a portion of the drying space SD is separated from the oxidation space SO or etching space SE only by the second inner partition 61. By moving the second inner partition 61, multiple substrates W can enter and exit the drying space SD. Since the drying space SD is positioned near the oxidation space SO or etching space SE only through the second inner partition 61, the time required to transport the substrates W to the drying space SD can be reduced, and the throughput of the substrate processing apparatus 1 can be increased. In addition, the structure of the substrate processing apparatus 1 can be simplified compared to the case where the oxidation space SO or etching space SE also serves as the drying space SD.

[0147] Next, a third embodiment will be described.

[0148] In Figures 9 to 10D below, configurations equivalent to those shown in Figures 1A to 8C are given the same reference numerals as in Figure 1A, etc., and their descriptions are omitted.

[0149] The main difference between the third embodiment and the second embodiment is that the second treatment tank 66 (see Figure 9), which holds the rinsing liquid in which multiple substrates W are immersed, is located in the drying space SD, and the drying space SD also serves as the rinsing space that supplies the rinsing liquid to the multiple substrates W.

[0150] Figure 9 is a schematic cross-sectional view showing a vertical cross-section of a processing unit 2 according to a third embodiment of the present invention. As shown in Figure 9, the second processing tank 66 includes an inner tank 42 for storing rinse liquid and an outer tank 43 for storing rinse liquid that overflows from the inner tank 42. The second processing tank 66 corresponds to a rinse processing tank for storing rinse liquid. The vertical distance from the surface of the rinse liquid in the inner tank 42 to the upper end of the drying space SD is greater than the diameter of the substrate W. The rinse liquid in the outer tank 43 is sent to the circulation piping 44 by the circulation pump 46 and supplied to the return nozzle 47 via the filter 45. The return nozzle 47 supplies the rinse liquid supplied from the circulation piping 44 into the inner tank 42 by discharging the rinse liquid from the discharge port 47p located in the inner tank 42.

[0151] Figure 9 shows an example where both the etching solution in the first treatment tank 41 and the rinsing solution in the second treatment tank 66 are pure water (labeled DIW in Figure 9). The rinsing solution is not limited to pure water; it may also be IPA (isopropyl alcohol), carbonated water, electrolyzed ionized water, hydrogen water, ozonated water, hydrochloric acid water at a diluted concentration (e.g., about 10-100 ppm), or ammonium hydroxide at a diluted concentration (e.g., about 10-100 ppm). The rinsing solution may be a different type of liquid from the etching solution.

[0152] The drying space SD is longer vertically than the oxidation space SO. The drying space SD is longer vertically than the etching space SE. The drying space SD is a rinse-drying space that also serves as a rinse space. Multiple movable partitions may include a third inner partition 67 that divides the rinse-drying space into a rinse space and a drying space SD. The rinse space is the space below the third inner partition 67, and the drying space SD is the space above the third inner partition 67. The rinse liquid in the second treatment tank 66 is supplied to multiple substrates W in the rinse space. The IPA vapor flowing out from the steam supply port 31 is supplied to multiple substrates W in the drying space SD.

[0153] Figures 10A, 10B, 10C, and 10D are schematic cross-sectional views showing the state of the processing unit 2 when an example of processing of the substrate W according to the third embodiment of the present invention is being performed. Hereafter, Figure 9 will be referred to. Figures 10A to 10D will be referred to as appropriate.

[0154] When processing multiple substrates W with the processing unit 2 according to the third embodiment, the multiple substrates W are moved between the oxidation space SO and the etching space SE, similar to the processing unit 2 according to the first embodiment, thereby performing one cycle including the oxidation process and the etching process multiple times.

[0155] After the final etching process, the traffic switching actuator 62 moves the second inner partition 61 from the closed position to the open position, thereby switching the processing unit 2 from a movement-prohibited state where multiple substrates W cannot move between the oxidation space SO and the drying space SD, to a movement-permitted state where multiple substrates W can move between the oxidation space SO and the drying space SD. In this state, as shown in Figure 10A, the sub-transport robot 12 moves multiple support bars 14 to move the multiple substrates W from the oxidation space SO to the drying space SD. Subsequently, the traffic switching actuator 62 moves the second inner partition 61 from the open position to the closed position.

[0156] After the multiple substrates W are moved to the drying space SD, which also serves as a rinsing space, the sub-transport robot 12 moves the multiple support bars 14, as shown in Figure 10A, to move the multiple substrates W within the drying space SD until the entire substrates W supported by the multiple support bars 14 are immersed in the rinsing liquid in the second processing tank 66. This performs a final rinsing process in which etching solution, particles, and other contaminants adhering to the substrates W are washed away with the rinsing liquid just before the substrates W are dried.

[0157] After the rinsing solution has been supplied to the multiple substrates W, as shown in Figure 10B, the sub-transport robot 12 moves the multiple support bars 14 to move the multiple substrates W in the drying space SD until the entire set of substrates W supported by the multiple support bars 14 is outside the second processing tank 66. Then, as shown in Figure 10C, a drying process is performed in which the drying space SD is filled with IPA vapor supplied from the vapor supply port 31. This removes any liquid adhering to the substrates W and dries the multiple substrates W supported by the multiple support bars 14 in the drying space SD. After that, the IPA vapor is discharged from the drying space SD through the second exhaust port 63, and the drying space SD is filled with a gas such as an inert gas.

[0158] After the multiple substrates W in the drying space SD have dried, the passage switching actuator 62 moves the second inner partition 61 from the closed position to the open position, and as shown in Figure 10D, the sub-transport robot 12 moves the multiple substrates W from the drying space SD to the oxidation space SO. Subsequently, the opening / closing actuator 56 moves the outer partition 55 from the closed position to the open position, and as shown in Figure 10D, the sub-transport robot 12 moves the multiple substrates W outside the processing unit 2 through the entrance / exit 54.

[0159] In the third embodiment, in addition to the effects of the first embodiment, the following effects can be achieved. Specifically, in the third embodiment, after supplying etching solution to multiple substrates W, rinsing solution is supplied to multiple substrates W. This allows etching solution and particles adhering to the substrates W to be washed away with the rinsing solution. If the etching solution and rinsing solution are different types of liquids, it is necessary to provide piping etc. for the etching solution and piping etc. for the rinsing solution. If both are liquids with the same name, it is not necessary to provide separate piping etc., and the structure of the substrate processing apparatus 1 can be simplified.

[0160] Other Embodiments The substrate W may be cooled before being immersed in the etching solution in the first processing tank 41. For example, a cooling gas such as an inert gas or air may be supplied to the substrate W in the oxidation space SO until the temperature of the substrate W drops to room temperature or near room temperature. In this case, the temperature of the cooling gas may be room temperature or below room temperature.

[0161] When supplying rinsing solution to substrates W before drying substrates W to which etching solution has been supplied, instead of immersing multiple substrates W in the rinsing solution in the second processing tank 66, the rinsing solution may be supplied to multiple substrates W in the first processing tank 41 by replacing the etching solution in the first processing tank 41 with rinsing solution while multiple substrates W are placed in the first processing tank 41.

[0162] When drying the substrate W, in addition to or instead of supplying vapor of an organic solvent such as IPA to the substrate W, the evaporation of liquid adhering to the substrate W may be promoted by reducing the air pressure in the drying space SD (in the first embodiment, the oxidation space SO which also serves as the drying space).

[0163] Instead of performing the three steps—oxidation of the molybdenum film 100, transport of the substrates W within the processing unit 2, and etching of the molybdenum oxide film 105—while holding multiple substrates W in the support frame 13 of the sub-transport robot 12, at least one of the three steps may be performed while holding multiple substrates W in a substrate holder other than the support frame 13.

[0164] If the amount of reduction in the thickness of the molybdenum film 100 is small, the number of oxidation and etching steps performed on one substrate W may be just one.

[0165] The substrate processing apparatus 1 is not limited to an apparatus for processing a disc-shaped substrate W, but may also be an apparatus for processing a polygonal substrate W.

[0166] You may combine two or more of the aforementioned components. You may also combine two or more of the aforementioned processes.

[0167] The support frame 13 is an example of a substrate holder. The heating lamp 21, ozone gas supply port 22, ozone gas piping 23, ozone gas valve 24, and ozone gas generator 25 are examples of oxidation means. The first processing tank 41, inner tank 42, outer tank 43, circulation piping 44, downstream piping 44d, upstream piping 44u, filter 45, circulation pump 46, return nozzle 47, and discharge port 47p are examples of etching means.

[0168] Furthermore, various design modifications can be made within the scope of the matters described in the patent claims. [Explanation of Symbols]

[0169] 1: Substrate processing equipment 8: Conveyor System 12: Sub-transport robot 13: Support frame (circuit board holder) 14: Support bar 21: Heating lamp (oxidation method) 22: Ozone gas supply port (oxidation means) 23: Ozone gas piping (oxidation method) 24: Ozone gas valve (oxidation method) 25: Ozone gas generator (oxidation method) 41: First processing tank (etching means) 42: Inner tank (etching means) 43: Outer tank (etching means) 44: Circulation piping (etching means) 44d: Downstream piping (etching means) 44u: Upstream piping (etching method) 45: Filter (etching means) 46: Circulation pump (etching means) 47: Return nozzle (etching means) 47p: Discharge port (etching means) 52: Partition 53: Fixed partition 55: Outer partition 57: First inner partition 61: Second inner partition 66: Second treatment tank 67: Third inner partition 100: Molybdenum film 101: Bulk molybdenum film 102: Surface layer of molybdenum film 103: Surface of molybdenum film 104: Native oxide film 105: Molybdenum oxide film 106: Surface of molybdenum oxide film SD: Drying space SE: Etching space SO: Oxidation space W: Circuit board

Claims

1. An oxidation step is performed in which, while supplying oxygen gas or ozone gas to a plurality of substrates arranged in an oxidation space within a substrate processing apparatus, the plurality of substrates in the oxidation space are heated, thereby changing the surface layer of the molybdenum film formed on each of the plurality of substrates to molybdenum trioxide, while the parts of the molybdenum film other than the surface layer are not changed to molybdenum trioxide. A first transport step involves transporting the plurality of substrates in the oxidation space to an etching space within the substrate processing apparatus, which is different from the oxidation space. A substrate processing method comprising: an etching step of supplying an etching solution to the plurality of substrates in the etching space, thereby dissolving the surface layer, which has been transformed into molybdenum trioxide, in the etching solution on each of the plurality of substrates, while leaving the portion of the molybdenum film other than the surface layer on the substrate.

2. The substrate processing method according to claim 1, wherein the oxidation step involves heating the plurality of substrates in the oxidation space while supplying the ozone gas to the plurality of substrates in the oxidation space.

3. The substrate processing method according to claim 1, wherein the etching solution is a water-containing solution with water as the main component.

4. The substrate processing method further includes a second transport step of transporting the plurality of substrates in the etching space to the oxidation space, The substrate processing method according to claim 1, wherein the substrate processing method comprises performing a single cycle including the oxidation step, the first transport step, the etching step, and the second transport step multiple times.

5. The oxidation process involves heating the multiple substrates in the oxidation space while holding the multiple substrates in a substrate holder and supplying oxygen gas or ozone gas to the multiple substrates in the oxidation space. The first transport step involves moving the substrate holder from the oxidation space to the etching space, thereby transporting the multiple substrates in the oxidation space to the etching space. The substrate processing method according to claim 1, wherein the etching step is performed by supplying the etching solution to the plurality of substrates in the etching space while the plurality of substrates are held by the substrate holder.

6. The substrate processing method according to claim 1, wherein the first transport step involves moving a first inner partition that forms a part of the oxidation space and a part of the etching space, and then transporting the plurality of substrates in the oxidation space to the etching space through the space where the first inner partition was located.

7. A second transport step of transporting the plurality of substrates in the etching space to the oxidation space, A substrate processing method according to any one of claims 1 to 6, further comprising a drying step of drying the plurality of substrates in the oxidation space after supplying the etching solution to the plurality of substrates.

8. A third transport step involves moving a second inner partition that forms a part of the drying space within the substrate processing apparatus, which is different from the oxidation space and etching space, and a part of the oxidation space or etching space, and then transporting the plurality of substrates in the etching space to the drying space through the space where the second inner partition was located. A substrate processing method according to any one of claims 1 to 6, further comprising a drying step of drying the plurality of substrates in the drying space after supplying the etching solution to the plurality of substrates.

9. A substrate processing method according to any one of claims 1 to 6, further comprising a rinsing step of supplying a rinse liquid, which has the same name as the etching solution but is physically different from the etching solution, to the plurality of substrates after supplying the etching solution to the plurality of substrates.

10. A partition that forms an oxidation space and an etching space, An oxidation means that, by supplying oxygen gas or ozone gas to a plurality of substrates arranged in the oxidation space and heating the plurality of substrates in the oxidation space, changes the surface layer of the molybdenum film formed on each of the plurality of substrates to molybdenum trioxide without changing the parts of the molybdenum film other than the surface layer to molybdenum trioxide, A transport system for transporting the multiple substrates in the oxidation space to the etching space which is different from the oxidation space, A substrate processing apparatus comprising: an etching means that supplies an etching solution to the plurality of substrates in the etching space, thereby dissolving the surface layer, which has been transformed into molybdenum trioxide, in the etching solution on each of the plurality of substrates, while leaving the portion of the molybdenum film other than the surface layer on the substrate.

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