JP2010129822A - Substrate processing device and processing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide substrate processing device and substrate processing method executing clean substrate processing at a low cost by preventing a substrate from being contaminated with a substance generated in radiating electron beams toward a substrate surface to perform predetermined substrate processing. <P>SOLUTION: Argon gas is supplied to an electron beam radiation area IR and the gas is exhausted from a surrounding area of the electron beam radiation area IR while the electron beams are being radiated. Thus, a contaminant generated by electron beam radiation to the substrate W is exhausted into an outer space of a processing space 41a together with the argon gas as exhaust gas to prevent the contaminant from being re-adhered to the substrate surface and from being dispersed into the whole of the processing space 41a. The contaminant is removed from the exhaust gas to generate a processing gas (once-used argon gas) and the processing gas is supplied to the processing space 41a. Thus, the processing space 41a is purged with the processing gas. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a semiconductor wafer, a glass substrate for photomask, a glass substrate for liquid crystal display, a glass substrate for plasma display, a substrate for FED (Field Emission Display), a substrate for optical disk, a substrate for magnetic disk, and a magneto-optical disk. The present invention relates to a substrate processing apparatus and a substrate processing method for performing predetermined substrate processing by irradiating various types of substrates such as substrates for use (hereinafter simply referred to as “substrates”) with an electron beam.

  A technique for irradiating the surface of a substrate with an electron beam is used in various fields, and one of them is a technique for modifying an interlayer insulating film in a semiconductor device manufacturing process. Conventionally, a silicon oxide film formed by thermal CVD or plasma CVD has been widely used as an interlayer insulating film of a semiconductor device. However, in order to reduce the capacitance between wirings, an organic silicon oxide film or an organic film not containing silicon is used. Adoption of dielectric constant films, so-called Low-k films, is progressing. Since sufficient strength cannot be obtained only by heat treatment when manufacturing this low dielectric constant film, a substrate processing technique for curing an interlayer insulating film by combining electron beam irradiation and heat treatment has been proposed (for example, Patent Documents). 1).

  In the apparatus described in Patent Document 1, a mounting table for supporting a semiconductor wafer is provided inside a vacuum chamber, and an electron beam irradiation mechanism for generating an electron beam is provided on a ceiling portion of the vacuum chamber. When the unprocessed semiconductor wafer is placed on the mounting table, the interlayer insulating film on the semiconductor wafer is subjected to a curing process as follows. That is, the inside of the vacuum chamber is evacuated through the exhaust pipe, and a predetermined atmospheric gas such as nitrogen gas is introduced from the gas introduction pipe, and the inside of the vacuum chamber has a predetermined pressure, for example, 1.33 to 66.5 KPa (10 to 500 Torr). Depressurize to the extent. Then, the semiconductor wafer is irradiated with an electron beam while the semiconductor wafer is heated to a predetermined temperature by a heater incorporated in the mounting table. Thereby, the interlayer insulating film on the semiconductor wafer is cured.

Japanese Patent No. 4056855 (FIG. 1)

  In the above-described conventional apparatus, since the curing process is performed in a state in which the vacuum chamber is decompressed, contaminants generated during the curing process spread throughout the vacuum chamber and condense on the inner wall of the vacuum chamber at room temperature. As a result, when a curing process is performed on the next semiconductor wafer, aggregates are present in the vacuum chamber as degassed particles, particles, or particle sources, and it is difficult to perform a clean curing process. . Furthermore, there is also a contamination accumulation in the electron beam irradiation mechanism itself, and the irradiation intensity is reduced, resulting in a reduction in processing efficiency.

  Further, while introducing nitrogen gas along the surface of the semiconductor wafer (substrate), the inside of the vacuum chamber is exhausted through an exhaust pipe provided at the bottom of the vacuum chamber, and the nitrogen gas is in a so-called flowing state. Therefore, a large amount of nitrogen gas is consumed during the curing process, which is one of the main factors for increasing the running cost.

  The present invention has been made in view of the above problems, and prevents contamination of a substrate by a substance generated when a predetermined substrate processing is performed by irradiating an electron beam toward the surface of the substrate, thereby reducing the cost of clean substrate processing. An object of the present invention is to provide a substrate processing apparatus and a substrate processing method that can be executed in the above-described manner.

  In order to achieve the above object, a substrate processing apparatus according to the present invention has a processing chamber having a processing space for performing substrate processing, and an electron beam that emits an electron beam toward the surface of the substrate disposed in the processing space. Generating means; moving means for scanning the electron beam irradiation area irradiated with the electron beam by moving the substrate relative to the electron beam generating means; and gas supply means for supplying an inert gas to the electron beam irradiation area. By exhausting around the electron beam irradiation area, pollutants generated by electron beam irradiation to the substrate are exhausted from the processing chamber together with inert gas as exhaust gas, and the contaminants are removed from the exhaust gas. And a gas circulation supply means for supplying the processing gas to the processing space.

  In the substrate processing method according to the present invention, the substrate is moved relative to the electron beam generating means while irradiating the surface of the substrate disposed in the processing space of the processing chamber with the electron beam from the electron beam generating means. A substrate processing method for performing a predetermined process on a substrate surface by scanning an electron beam irradiation region irradiated with an electron beam in order to achieve the above-mentioned object. While supplying an inert gas, exhausting the periphery of the electron beam irradiation area exhausts the contaminants generated by the electron beam irradiation to the substrate as an exhaust gas together with the inert gas, and exhausts the substrate. A processing gas obtained by removing contaminants from the gas is supplied to the processing space.

  In the invention configured as described above (substrate processing apparatus and substrate processing method), the electron beam generating means irradiates the electron beam toward the substrate surface, and the substrate moves relative to the electron beam generating means, whereby the electron beam is generated. The irradiation region is scanned and substrate processing by electron beam irradiation is executed. During the electron beam irradiation, an inert gas is supplied to the electron beam irradiation region, while the periphery of the electron beam irradiation region is exhausted. Thus, contaminants generated by electron beam irradiation on the substrate are exhausted from the processing chamber as exhaust gas together with the inert gas. As a result, reattachment of contaminants to the substrate surface and diffusion of contaminants to the entire processing space are prevented. Further, in the present invention, the processing gas obtained by removing the pollutants from the exhaust gas, that is, the inert gas once used for the substrate processing is supplied to the processing space, and the processing space is purged with the inert gas. Therefore, the adhesion of contaminants to the processing chamber is effectively prevented. In addition, since the inert gas used for the substrate processing is reused, the running cost can be suppressed.

  Here, as the gas circulation supply means, for example, a circulation path forming unit that forms a gas circulation path that returns from the periphery of the electron beam irradiation region to the processing space through the outer space of the processing chamber, and a gas circulation path is provided. A circulation fan that circulates gas along the gas circulation path and a removal unit that is provided on the gas circulation path and removes contaminants from the exhaust gas that circulates along the gas circulation path may be used. . In this way, the exhaust gas (inert gas + contaminant) is quickly exhausted from the periphery of the electron beam irradiation region by the circulation fan. In addition, the pollutant is surely removed from the exhaust gas flowing from the periphery of the electron beam irradiation area to the removal section, so that a processing gas containing no pollutant, that is, an inert gas, is obtained, and the purge process is performed well. Can do.

  The removal unit includes a decomposition processing unit that is provided on the gas circulation path and decomposes contaminants contained in the exhaust gas into moisture and carbon dioxide, and a processing gas supply port to the processing space on the gas circulation path. And an adsorption tower that is provided between the gas generator and the decomposition treatment unit and adsorbs moisture and carbon dioxide from the exhaust gas. Various methods can be used to decompose the pollutant into moisture and carbon dioxide. For example, the exhaust gas can be heated and then decomposed into moisture and carbon dioxide using a catalyst.

  In addition, the moisture and carbon dioxide thus generated are adsorbed by the adsorption tower and removed from the exhaust gas. However, the adsorption performance of the adsorption tower decreases as the adsorption removal proceeds. Therefore, a plurality of adsorption towers are prepared in advance, and while the adsorption treatment of moisture and carbon dioxide is performed by one adsorption tower, the remaining adsorption towers are subjected to regeneration treatment, and the adsorption performance of moisture and carbon dioxide. May be configured to recover. In this case, by sequentially using a plurality of adsorption towers, moisture and carbon dioxide can always be removed from the exhaust gas with high efficiency, and the processing gas can be made into a relatively high purity inert gas.

  Furthermore, it is desirable to use an unused gas, that is, a fresh one, as the inert gas supplied by the gas supply means. In this way, a fresh inert gas is supplied to the electron beam irradiation region to perform the substrate processing well, and the processing space surrounding the substrate can be purged using the processing gas, and the efficiency of the inert gas can be increased. Can be used effectively.

  According to the present invention, during the electron beam irradiation, an inert gas is supplied to the electron beam irradiation region, while the surroundings of the electron beam irradiation region are evacuated to cause contamination caused by the electron beam irradiation to the substrate. Since the substance is exhausted from the processing chamber together with the inert gas as an exhaust gas, it is possible to effectively prevent the re-attachment of the contaminant to the substrate surface and the diffusion of the contaminant to the entire processing space. Further, since the processing gas (inert gas) obtained by removing the contaminants from the exhaust gas is supplied to the processing space and the processing space is purged with the inert gas, the processing chamber is contaminated. Substance adhesion can be effectively prevented. Therefore, substrate processing using electron beam irradiation can be performed at low cost and with high cleanliness.

(Schematic configuration of substrate processing system)
FIG. 1 is a view showing a substrate processing system equipped with an electron beam curing apparatus which is an embodiment of a substrate processing apparatus according to the present invention. In this substrate processing system, the unprocessed substrate W taken out from a FOUP (Front Opening Unified Pod) that accommodates a plurality of substrates W in a sealed state is subjected to heat treatment and curing treatment, and then the substrate W is cooled to room temperature. Then, a series of processing of returning to FOUP is executed. That is, the substrate processing system has a load lock chamber 2, a hot plate 3, two electron beam curing devices 4 A and 4 B, a cold plate 5, a load plate around the transfer robot chamber 1 around the transfer robot chamber 1. A lock chamber 6 is arranged. Further, shutters 72A, 73, 74A, 74B, 75, and 76A are provided between the transfer robot chamber 1, the load lock chamber 2, the hot plate 3, the electron beam curing devices 4A and 4B, the cold plate 5, and the load lock chamber 6. Are arranged respectively.

The load lock chamber 2 is for a loader, and has a loader opening (not shown) on the side surface facing the transfer robot 8 that loads and unloads the substrate W with respect to the FOUP. Further, the load lock chamber 2 is provided with a shutter 72B for opening and closing the loader opening. In this embodiment, the load lock chamber 2 is an atmospheric atmosphere, and the transfer robot 8 moves from the FOUP to the unprocessed substrate W, that is, an uncured interlayer insulating film on the surface (reference symbol F in FIG. 6) with the shutter 72B opened. ) Coated substrate W or CVD (Chemical
The substrate W formed by Vapor Deposition) can be carried into the load lock chamber 2. On the other hand, the transfer robot 11 disposed in the transfer robot chamber 1 moves the hand (not shown) to the load lock chamber 2 to receive the unprocessed substrate W and transfers it to the transfer robot chamber 1 with the shutter 72A opened. .

  The transfer robot chamber 1 is adjusted to a nitrogen gas atmosphere, and its internal pressure is substantially atmospheric pressure. In this regard, the hot plate 3 and the cold plate 5 are the same. On the other hand, the electron beam curing devices 4A and 4B are maintained in an argon gas atmosphere adjusted to atmospheric pressure or slightly positive pressure during electron beam irradiation. This point will be described in detail later.

  Upon receipt of the unprocessed substrate W, the transfer robot 11 transfers the substrate W to the hot plate 3, the electron beam curing device 4A (or 4B), and the cold plate 5 in this order. On the other hand, the hot plate 3, the electron beam curing device 4A (or 4B), and the cold plate 5 on which the substrate W has been transferred are respectively subjected to a heating process, a curing process, and a cooling process to cure the interlayer insulating film F to have desired characteristics. (Low dielectric constant film and sufficient strength). Since the configuration and operation of the hot plate 3 and the cold plate 5 are well known in the art, description thereof will be omitted here, while the electron beam curing apparatuses 4A and 4B correspond to the substrate processing apparatus of the present invention. This will be explained in detail.

  When the desired characteristics are given to the interlayer insulating film F as described above, the transfer robot 11 takes the substrate W from the cold plate 5 into the transfer robot chamber 1. Then, with the shutter 76A opened, the transport robot 11 moves the hand (not shown) holding the substrate W to the load lock chamber 6 for unloading and carries out the substrate W. In this embodiment, the load lock chamber 6 is also in an atmospheric atmosphere like the load lock chamber 2, and the transfer robot 8 can take out the substrate W into the load lock chamber 6 with the shutter 76B opened and store it in the FOUP. ing.

(Configuration and operation of electron beam cure device)
FIG. 2 is a sectional view showing an electron beam curing apparatus which is an embodiment of the substrate processing apparatus according to the present invention. FIG. 3 is a perspective view and a partially enlarged bottom view of the barge box as seen from below. FIG. 4 is a block diagram showing an electrical configuration of the electron beam curing apparatus shown in FIG. 5 is a diagram showing a gas supply system in the electron beam cure apparatus shown in FIG. The electron beam curing apparatuses 4A and 4B have the same configuration and are configured as follows.

  The electron beam curing device 4A (4B) is a device for curing the interlayer insulating film by irradiating the electron beam emitted from the electron beam generating units 40A and 40B toward the surface Wf of the substrate W, and is configured as follows. ing. The electron beam curing apparatus 4A (4B) is provided with a processing chamber 41 having a processing space 41a for executing a curing process. A substrate passage port 41b having a shape into which the hand of the transfer robot 11 (FIG. 1) can be inserted is provided on the side wall of the processing chamber 41 on the transfer robot side (left hand side in FIG. 2). In contrast, a shutter 74A (74B) is provided. Then, when the substrate W is carried in / out by the transfer robot 11, the shutter 74A (74B) moves upward in response to an opening command from the control unit 42 that controls the entire electron beam curing device, thereby opening the substrate passage port 41b. Conversely, when performing a curing process as will be described later, the shutter 74A (74B) moves downward as shown in FIG. 2 to close the substrate passage opening 41b in response to a closing command from the control unit 42.

  In the processing space 41 a of the processing chamber 41, a stage 44 that can hold the substrate W is provided so as to be movable in the movement direction X and can be moved up and down in the vertical direction Z. A plurality of spherical proximity balls (not shown) are provided on the upper surface of the stage 44, and the back surface of the substrate W can be supported by the spherical top of each ball. As a result, the substrate W is supported in a state of being slightly lifted from the upper surface of the stage 44 in a horizontal state with the substrate surface Wf facing upward. Only a plurality of pins project from the upper surface of the stage 44 so as to surround the peripheral edge of the substrate W supported in this manner, thereby preventing the displacement of the substrate W in the horizontal direction. In this embodiment, the stage 44 has a built-in heater 45, and the substrate 45 is heated from the back side by operating the heater 45 in accordance with an operation command from the control unit 42 to cure the substrate temperature. The temperature can be raised to a temperature suitable for the temperature, for example, about 350 to 400 ° C. In the case of a processing application in which the uniformity of the temperature of the substrate W is not strictly required, the proximity ball may be eliminated and the substrate W may be placed on the stage 44 in contact.

  The stage 44 configured in this way is connected to a stage drive unit 46. The stage drive unit 46 includes an elevating drive unit 46a that drives the stage 44 up and down in the up-down direction Z, and a linear drive unit 46b that integrally drives the elevating drive unit 46a and the stage 44 in the moving direction X. When the linear drive unit 46b is actuated in accordance with the movement command from the control unit 42, the elevation drive unit 46a and the stage 44 are integrally driven in the movement direction X to move the substrate W over a predetermined substrate movement range MR. It can be moved back and forth. Thus, in this embodiment, the stage 44 and the linear drive part 46b function as the “moving means” of the present invention.

  Further, when the lifting / lowering drive unit 46a is actuated in accordance with the lifting / lowering command from the control unit 42, the stage 44 is lifted / lowered to transfer the substrate W to the transfer height position (broken line height position in FIG. 2) and the processing height position (FIG. 2). (The one-dot chain line and the solid line height position). In this embodiment, when carrying in / out the substrate W, as shown by the broken line in FIG. 2, the stage 44 is moved to the transfer robot chamber 1 side (left hand side in the figure) and the transfer height position is set. (Transport position). When performing the curing process, the stage 44 is moved to the anti-transport robot chamber 1 side (the right hand side in the figure) after being raised to the processing height position. Then, after the curing process is completed, an operation reverse to the above is performed to move the stage 44 to the original transport position.

  In this embodiment, the purge box 47 is arranged in the processing chamber 41 so as to cover the surface Wf of the substrate W moving in the substrate moving range MR as described above from above. The purge box 47 has a rectangular parallelepiped shape as shown in FIG. 3, the length Ly in the width direction Y orthogonal to the movement direction X is larger than the outer diameter of the substrate W, and the length Lx in the movement direction X is the substrate. It is more than twice the outer diameter of W. Therefore, while the substrate W is moving in the movement direction X, the substrate W always faces the lower surface plate 47a of the purge box 47, and the atmosphere AP on the substrate surface side is regulated by the lower surface plate 47a. That is, the substrate surface side atmosphere AP formed between the substrate surface Wf and the lower surface plate 47a is significantly smaller than the processing space 41a and is blocked from the surroundings. The distance between the substrate surface Wf and the lower surface plate 47a is set to 1 to 10 mm. In the above embodiment, the length Lx in the movement direction X of the purge box 47 is at least twice the outer diameter of the substrate W, but the atmosphere in the electron beam irradiation region IR by the purge box 47 and the exhaust unit 49 May be smaller than the outer diameter of the substrate W.

  Inside the purge box 47, as shown in FIG. 2, hollow chambers 47 b to 47 d extending in the width direction Y are arranged in parallel in the movement direction X. Among these, the central hollow chamber 47c is a hollow chamber for electron beam irradiation, and a part of the electron beam generating units 40A and 40B is attached to the hollow chamber 47c. In the present embodiment, the electron beam generating units 40A and 40B both have the same configuration, and can scan the electron beam with a scan width of 150 mm in the width direction Y. In this embodiment, the two electron beam generating units 40A, 40B are staggered in the width direction Y on the opposite side of the substrate surface Wf (upper side in FIG. 2) with respect to the lower surface plate (plate member) 47a. The electron beam can be scanned in the width direction Y with a scan width of about 300 mm. In the above embodiment, the “electron beam generating means” of the present invention is configured by arranging two electron beam generating units 40A and 40B with a scan width of 300 mm, but has a scan width of 300 mm. You may make it comprise with one electron beam generation unit.

  Each electron beam generating unit 40A, 40B has an electron gun (not shown) that emits an electron beam (reference numeral EB in FIG. 7) from a filament that is an electron emitting member. The filament of this electron gun is accommodated in the accommodating chamber 40b of the vacuum vessel 40a. In the vacuum vessel 40a, an electron passage 40c extends from the storage chamber 40b in the direction in which the electron beam EB is emitted (downward in this embodiment). A cylindrical electromagnetic coil that functions as an electromagnetic deflection lens is provided around the communicating portion of the storage chamber 40b and the electron passage 40c, and the electron beam EB emitted from the electron gun can be scanned in the width direction Y. It has become. Corresponding to the scanning of the electron beam EB, the electron passage 40c expands in a fan shape toward the tip at the communication portion with the cylindrical storage chamber 40b. That is, in the electron passage 40c, only the width in the width direction Y is gradually enlarged, and the width in the movement direction X is constant. Therefore, the tip of the electron passage 40c extends long and narrow with the width direction (scan direction) Y as the longitudinal direction. The rear end portion of the electron passage 40c is attached to the center of the ceiling of the processing chamber 41, and the front end portion is attached to the hollow chamber 47c of the purge box 47 so that the electron beam generating units 40A and 40B are fixed to the processing chamber 41. Has been placed.

  In the electron beam generating units 40A and 40B configured as described above, when the electron beam EB emitted from the electron gun passes through the electron passage 40c, the emission direction Y is deflected by the electromagnetic coil. Thereby, the emission axis of the electron beam EB moves along the width direction (scan direction) Y. The electron beam EB reaches the window 40d provided at the tip of the vacuum vessel 40a.

  Each window portion 40d is a component for emitting an electron beam EB emitted from the electron gun to the outside of the vacuum vessel 40a. At the tip of the vacuum vessel 40a (the end portion of the electron passage 40c), the width direction (scan direction). ) It is finished in a rectangular shape extending to Y (see FIG. 3B). Each rectangular window 40d faces a rectangular opening 47e for electron beam EB irradiation formed at the center of the lower surface of the purge box 47 as shown in FIG. The electron beam emitted from the substrate passes through the opening 47e and is irradiated toward the substrate surface Wf. In this embodiment, as shown in FIG. 5B, the two window portions 40d are staggered in the same manner as the electron beam generating units 40A and 40B.

  Further, an argon gas supply unit 48 is connected to the upper surface of the central hollow chamber 47c of the purge box 47, and the argon gas supply unit 48 is operated according to a command from the control unit 42, so that it is not used in the central hollow chamber 47c. Of argon gas is supplied. Since a plurality of gas supply ports 47f are formed in the lower surface of the central hollow chamber 47c so as to surround the opening 47e, the argon gas supplied as described above causes the electron beam EB to be transmitted from the side thereof. It discharges toward the opposing substrate surface Wf while surrounding the periphery. Thus, an electron beam irradiation region (reference numeral IR in FIG. 7) in which the electron beam EB is irradiated toward the substrate surface Wf in the substrate surface side atmosphere AP formed between the substrate surface Wf and the lower surface plate 47a is an argon gas. It becomes an atmosphere. Thus, in this embodiment, the argon gas supply unit 48 functions as the “gas supply means” of the present invention.

  The purge box 47 is provided with an upstream hollow chamber 47b and a downstream hollow chamber 47d so as to sandwich the above-described central hollow chamber 47c. Further, as shown in FIG. 5, one end of an exhaust pipe 43a is connected to both the hollow chambers 47b and 47d. The other end of each exhaust pipe 43a is connected to a circulation fan 49a. When the circulation fan 49a is activated in response to an operation command from the control unit 42, the electron beam irradiation is performed via the purge box 47 and each exhaust pipe 43a. The area around the region IR is exhausted. That is, a plurality of exhaust ports 47g are formed in the lower surfaces of the hollow chambers 47b and 47d, and the electron beam irradiation region IR in the substrate surface side atmosphere AP formed between the substrate surface Wf and the lower surface plate 47a. A region other than that, that is, a non-irradiated region (reference NIR in FIG. 7) and the hollow chambers 47b and 47d communicate with each other. Therefore, when the circulation fan 49a is activated, the non-irradiation region NIR is exhausted to the outer space of the processing chamber 41 through the exhaust port 47g, the hollow chambers 47b and 47d, and the exhaust pipe 43a, and the electron beam EB is emitted to the substrate surface Wf. Contaminants generated upon irradiation can be reliably removed from the substrate surface side atmosphere AP together with the argon gas, and diffusion of the contaminants outside the substrate surface side atmosphere AP can be prevented.

  In the present embodiment, as shown in FIG. 5, the end of the exhaust pipe 43a on the side opposite to the purge box is connected to the suction port of the circulation fan 49a. In addition, an inlet of the decomposition processing unit 49b is connected to the outlet side of the circulation fan 49a via a pipe 43b. The decomposition processing unit 49b has a heater and a catalyst. After the exhaust gas sent from the circulation fan 49a is heated by the heater, the high temperature contaminant is decomposed into moisture and carbon dioxide by the catalyst. It has a function to do. Therefore, the exhaust gas sent out from the decomposition processing unit 49b is a gas containing argon gas, moisture, and carbon dioxide.

  Two adsorption towers 49c1 and 49c2 are connected in parallel to the outlet of the decomposition processing unit 49b via a pipe 43c, and an adsorption tower switching unit 49c3 (see FIG. 4) formed by combining a plurality of valves is used as a control unit 42. As a result of the control, one of the two adsorption towers 49c1 and 49c2 can be selectively connected to the decomposition processing unit 49b. That is, when the adsorption tower switching unit 49c3 is actuated in response to a command from the control unit 42 and one of the adsorption towers is connected to the decomposition processing unit 49b and the circulation filter 49d, exhaust gas ( Argon gas + moisture + carbon dioxide) is fed, and moisture and carbon dioxide are adsorbed by the adsorption tower to generate a processing gas (argon gas). The processing gas generated in this way is purged from the ceiling end of the processing chamber 41 into the processing space 41a through the piping 43d, the circulation filter 49d and the piping 43e. In the present embodiment, the combination of the decomposition processing unit 49b and the adsorption towers 49c1 and 49c2 corresponds to the “removal unit” of the present invention, but the configuration for removing contaminants from the exhaust gas is not limited to this. Alternatively, a configuration in which contaminants are removed by other methods may be employed.

  On the other hand, in the non-selection adsorption tower, a regeneration process for recovering the adsorption performance by releasing the moisture and carbon dioxide held by adsorption is executed. In this way, while the processing gas is generated in one of the adsorption towers, in parallel with the generation of the processing gas, regeneration processing is performed in the remaining adsorption towers to prepare for the generation of the next processing gas. Can do. In this way, the processing space 41a can be continuously purged with the processing gas (argon gas) by switching the adsorption tower.

  Thus, in the present embodiment, the purge box 47 and the pipes 43a to 43e form a gas circulation path that returns from the periphery of the electron beam irradiation region IR to the processing space 41a again through the outer space of the processing chamber 41. That is, the purge box 47 and the pipes 43a to 43e function as the “circulation path forming part” of the present invention, and the exhaust gas (argon gas + contaminant) circulates through the purge box 47 and the pipes 43a to 43c. , 43e flows through the processing gas (argon gas). In the present embodiment, the “circulation supply unit” of the present invention is configured by the circulation path forming unit, the circulation fan 49a, and the removal unit (decomposition unit 49b + adsorption towers 49c1, 49c2) formed in this way. .

  In this embodiment, one end of a pipe 43f is connected to the bottom surface of the processing chamber 41 as shown in FIG. The other end of the pipe 43f is connected to the pipe 43a, and the atmosphere excluding the substrate surface side atmosphere AP in the processing space 41a can be exhausted. That is, an atmosphere other than the substrate surface side atmosphere AP can be exhausted to the gas circulation path via the pipe 43f. For this reason, part of the processing gas purged into the processing space 41a as described above is returned to the gas circulation path via the pipe 43f. In this embodiment, since fresh argon gas is supplied to the electron beam irradiation region IR and the processing gas is purged into the processing space 41a along the gas circulation path, the processing space 41a is supplied by supplying argon gas. However, an amount of processing gas corresponding to the supply of argon gas is discharged from the gap between the shutter 74A (74B) and the processing chamber 41, and the pressure in the processing space 41a is maintained at almost atmospheric pressure or slightly positive pressure. ing.

  Next, the operation of the electron beam curing apparatus 4A (4B) configured as described above will be described in detail with reference to FIG. 6 and FIG. FIG. 6 is a flowchart showing the operation of the electron beam curing apparatus of FIG. FIG. 7 is a diagram schematically showing the vicinity of the electron beam irradiation region. The electron beam curing devices 4A and 4B have the same configuration, and the operation of each device is also the same. Therefore, in the substrate processing system according to this embodiment, the substrate W that has been subjected to the heat treatment by the hot plate 3 is transferred to one of these electron beam curing devices 4A and 4B and undergoes the following curing (curing) processing. Here, the operation in the electron beam curing apparatus 4A will be described.

  In the electron beam curing apparatus 4A, the shutter 74A remains closed until the substrate W is transported, but the pressure is adjusted so that the internal pressure of the processing space 41a becomes atmospheric pressure or slightly positive pressure. The control unit 42 controls each part of the apparatus as follows in accordance with a program stored in a memory (not shown), and performs a curing process on the substrate W transported from the hot plate 3 by the transport robot 11. . Note that the internal pressure of the processing space 41a may be adjusted slightly higher than the atmospheric pressure.

  Before the substrate W is transferred from the hot plate 3 to the electron beam curing device 4A, the shutter 74A is opened and the substrate passage port 41b is opened (step S1). Then, the transfer robot 11 carries the substrate W taken out from the hot plate 3 into the processing chamber 41 through the substrate passage port 41b and places it on the stage 44 (step S2). Then, after the loading of the substrate W is completed, the shutter 74A is closed (step S3). An uncured interlayer insulating film F is formed on the surface Wf of the substrate W thus carried in, and is cured by receiving a curing process (steps S4 to S6) to be described below and has desired characteristics. Is granted. In FIG. 7, the uncured portion of the interlayer insulating film F is outlined, the portion being cured is satin, and the portion after the curing is shaded.

  In step S4, the argon gas supply unit 48 starts supplying argon gas, and the argon gas is introduced into the substrate surface side atmosphere AP, particularly the electron beam irradiation region IR and the range surrounding it through the central hollow chamber 47c and the gas supply port 47f. Is discharged to form an argon gas atmosphere. In this embodiment, the electron beam irradiation region IR is adjusted to atmospheric pressure or slightly positive pressure. At the same time or before or after this, the operation of the exhaust unit 49 is started, and the substrate surface side atmosphere AP, particularly the non-irradiation region NIR, is exhausted through the exhaust port 47g and the hollow chambers 47b and 47d. In this embodiment, energization of the heater 45 is started before the substrate is carried in and heating of the substrate W is started and the temperature is raised to a predetermined temperature in advance. However, the operation timing of the heater 45 is limited to this. It can be arbitrarily set according to process conditions such as the type of the substrate W and the interlayer insulating film F.

  When preparations for electron beam irradiation are completed as described above, emission of electron beams from the electron beam generation units 40A and 40B is started, the stage 44 is driven, and scanning of the substrate W is started, so The curing process for the insulating film F is started (step S5). That is, the stage 44 is lifted from the transfer position (the position indicated by the broken line in FIG. 2) and positioned in the vicinity of the lower surface plate 47a of the purge box 47, and then in the (+ X) direction, that is, from the left hand side to the right hand side in FIG. The substrate W moves and passes through the electron beam irradiation region IR. In addition, the electron beam generating units 40A and 40B operate in advance in conjunction with the moving operation of the stage 44 to emit a stable electron beam toward the substrate surface Wf. For this reason, as shown in FIG. 6, an electron beam is irradiated in an argon gas atmosphere to a portion (a satin portion in the figure) located in the electron beam irradiation region IR of the interlayer insulating film F formed on the substrate surface W. To be cured. This electron beam irradiation is continuously performed while the substrate W is moved, and the entire interlayer insulating film F is cured.

  Further, by irradiating the interlayer insulating film F on the substrate surface Wf with an electron beam as described above, gaseous contaminants such as organic substances and hydrocarbons are generated, but they flow from the electron beam irradiation region IR. Together with the argon gas, the gas is discharged from the processing space 41a through the exhaust port 47g, the hollow chambers 47b and 47d, and the pipe 43a. Therefore, the contaminants are efficiently diffused from the substrate surface side atmosphere AP without diffusing into the processing space 41a from the substrate surface side atmosphere AP, that is, a relatively narrow space sandwiched between the lower surface plate 47a of the purge box 47 and the substrate surface Wf. It is forcibly discharged. As a result, (1) the problem that contaminants diffuse into the processing space 41a and adhere to the inner wall surface of the processing chamber 41, the stage 44, etc., becomes a source of degassing and particles, and (2) the substrate surface Wf and interlayer It is possible to effectively prevent the problem of redeposition to the insulating film F and (3) the problem of contamination accumulation in the opening of the electron beam generating unit and a decrease in irradiation intensity.

  Further, as described above, the pollutant together with the argon gas is discharged as exhaust gas from the processing space 41a to the outer space, and this exhaust gas passes through the decomposition processing unit 49b and the adsorption tower 49c1 (or 49c2). Contaminants in the exhaust gas are removed. Thus, a processing gas (argon gas) is generated and supplied to the processing space 41a. Thus, the operation of the circulation fan 49a causes the argon gas to circulate along the gas circulation path. This gas circulation operation is continuously performed during the electron beam irradiation.

  As described above, the movement of the substrate W causes the electron beam irradiation region IR to scan in the X direction with respect to the entire surface of the substrate surface Wf, that is, the entire substrate surface Wf passes through the electron beam irradiation region IR and the substrate W moves to the substrate movement range. When reaching the downstream end of the MR, the movement of the stage 44 is stopped to complete the substrate movement. With this substrate movement completion as a trigger (step S6), the operation of the electron beam generating unit 40A is stopped first (step S7), the irradiation of the electron beam is stopped, and then argon gas is supplied and exhausted by the exhaust unit 49. The operation is stopped (step S8). Further, the supply of argon gas and the exhaust operation by the exhaust unit 49 are stopped, and the stage 44 returns to the transfer position by the operation reverse to the above-described stage operation (step S9). Note that the heater 45 may be stopped at this timing when the processing of all the scheduled substrates is completed. As described above, in this embodiment, the substrate W is reciprocated in the X direction. However, since the interlayer insulating film F is cured by irradiating the electron beam only during the forward movement, the efficiency is reduced in a short time. The curing process can be executed automatically. Of course, the curing process may be performed during the backward movement (movement from the right hand side to the left hand side in FIG. 2) in the same manner as during the forward movement, depending on the process conditions such as the type and thickness of the interlayer insulating film F. Can be selected as appropriate. Further, the reciprocating movement may be performed a plurality of times depending on the process conditions.

  When the curing process is completed as described above, the shutter 74A is opened and the substrate passage opening 41b is opened (step S10). Then, the transfer robot 11 receives the cured substrate W from the stage 44, carries it out of the processing chamber 41 (step S11), and transfers it to the cold plate 5. After the substrate is carried out, the shutter 74A is closed (step S12), and it waits for the next substrate W to be carried.

  As described above, in the present embodiment, while performing electron beam irradiation, argon gas is supplied to the electron beam irradiation region IR in an atmospheric pressure or slightly positive pressure atmosphere, while surrounding the electron beam irradiation region IR. Since the exhaust gas is exhausted, the contaminants generated by the electron beam irradiation onto the substrate W can be exhausted to the outer space of the processing space 41a together with the argon gas as an exhaust gas. As a result, it is possible to effectively prevent the reattachment of contaminants to the substrate surface and the diffusion of contaminants to the entire processing space 41a. Further, contaminants are removed from the exhaust gas to generate a processing gas, that is, an argon gas used for substrate processing, and the processing gas is supplied to the processing space 41a so that the processing space 41a is treated with the processing gas (argon gas). Since purging is performed, adhesion of contaminants to the processing chamber 41 can be effectively prevented.

  In this embodiment, the electron beam irradiation region IR is not used, that is, a fresh argon gas is supplied to perform the curing process well, and the processing space 41a surrounding the substrate W is treated with a processing gas (once used). Purge processing is performed using the argon gas). Therefore, argon gas is efficiently used, and the curing process can be performed satisfactorily with a low running cost.

(Other)
The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, in the above embodiment, argon gas is used as the inert gas, but it goes without saying that an inert gas other than argon gas (for example, xenon gas or nitrogen gas) may be used.

  Further, in the above embodiment, the argon gas is discharged substantially parallel to the electron beam EB so as to surround the electron beam irradiation region IR, and the argon gas and the contaminant are discharged together to manage the atmosphere of the non-irradiation region NIR. Although the atmosphere management of the substrate surface side atmosphere AP is performed by this, the following management mode of the substrate surface side atmosphere AP may be adopted.

  In the above embodiment, the electron beam is irradiated onto the substrate surface Wf using the two electron beam generating units 40A and 40B. However, the number and arrangement of the electron beam generating units are arbitrary. In the above embodiment, the electron beam generating unit is fixedly arranged and the substrate W is moved in the X direction between the substrate movement ranges MR. However, both of them are moved together, the substrate is fixed and the electron beam is generated. The substrate may be relatively moved in the X direction by integrally moving the unit and the purge box.

  Moreover, in the said embodiment, although the two adsorption towers 49c1 and 49c2 are provided so that switching is possible, it is arbitrary about the number, arrangement | positioning, etc. of an adsorption tower. For example, moisture and carbon dioxide may be adsorbed and removed from the exhaust gas by a single adsorption tower. In this case, it is desirable to perform the regeneration process while not performing the curing process. Alternatively, three or more adsorption towers may be provided and the adsorption towers that perform the adsorption process may be sequentially switched by the adsorption tower switching unit.

  In the above embodiment, the present invention is applied to an electron beam curing apparatus that irradiates an electron beam toward the substrate surface Wf to cure the uncured interlayer insulating film F. The object is not limited to this, and the present invention can be applied to all substrate processing apparatuses that perform predetermined substrate processing by irradiating an electron beam toward the substrate surface.

Further, the dielectric constant (k value) of the interlayer insulating film is further lowered from the present k = 3 to about k = 2.2 to 2.4, that is, Ultra.
In order to obtain a low-k film, an organic substance such as porogen is introduced into the low-k film to generate vacancies in the low-k film, and this is irradiated with an electron beam to decompose and gasify the porogen. Thus, it can be applied to a substrate processing method for obtaining a stronger film by gasifying terminal groups such as hydrogen at the same time as obtaining pores.

  The present invention relates to a semiconductor wafer, a glass substrate for photomask, a glass substrate for liquid crystal display, a glass substrate for plasma display, a substrate for FED (Field Emission Display), a substrate for optical disk, a substrate for magnetic disk, a substrate for magneto-optical disk, etc. The present invention can be applied to a substrate processing apparatus and a substrate processing method that perform predetermined processing by irradiating the surface of the entire substrate including the electron beam.

It is a figure showing a substrate processing system equipped with one embodiment of a substrate processing device concerning this invention. It is sectional drawing which shows the electron beam curing apparatus which is one Embodiment of the substrate processing apparatus concerning this invention. It is the perspective view which looked at the barge box from the lower part. FIG. 3 is a block diagram showing an electrical configuration of the electron beam curing apparatus shown in FIG. 2. It is a figure which shows the gas supply system in the electron beam cure apparatus shown in FIG. It is a flowchart which shows operation | movement of the electron beam cure apparatus of FIG. It is a figure which shows typically the vicinity of the electron beam irradiation area | region IR.

Explanation of symbols

4A, 4B ... Electron beam curing device (substrate processing device)
40A, 40B ... Electron beam generation unit 41 ... Processing chamber 41a ... Processing space 43a-43e ... Piping (circulation path forming part)
44 ... Stage (moving means)
46. Stage drive unit (moving means)
46b ... Linear drive (moving means)
47 ... Purge box (circulation path forming part)
48. Argon gas supply unit (gas supply means)
49a ... circulation fan 49b ... decomposition processing unit (removal part)
49c1, 49c2 ... Adsorption tower EB ... Electron beam F ... Interlayer insulating film IR ... Electron beam irradiation region IR
W ... Substrate Wf ... Substrate surface X ... Moving direction

Claims (6)

A processing chamber having a processing space for performing substrate processing;
Electron beam generating means for emitting an electron beam toward the surface of a substrate disposed in the processing space;
Moving means for scanning an electron beam irradiation region irradiated with an electron beam by moving the substrate relative to the electron beam generating means;
Gas supply means for supplying an inert gas to the electron beam irradiation region;
By exhausting the periphery of the electron beam irradiation region, the contaminant generated by the electron beam irradiation to the substrate is exhausted from the processing chamber as an exhaust gas together with the inert gas, and the contamination is exhausted from the exhaust gas. A substrate processing apparatus comprising gas circulation supply means for supplying a processing gas obtained by removing a substance to the processing space. The gas circulation supply means includes
A circulation path forming unit that forms a gas circulation path that returns from the periphery of the electron beam irradiation region to the processing space through the outer space of the processing chamber;
A circulation fan that is provided on the gas circulation path and circulates the gas along the gas circulation path;
The substrate processing apparatus according to claim 1, further comprising: a removing unit that is provided on the gas circulation path and removes the contaminants from the exhaust gas flowing along the gas circulation path. The removing unit is
A decomposition processing unit that is provided on the gas circulation path and decomposes the contaminant contained in the exhaust gas into moisture and carbon dioxide;
An adsorption tower provided on the gas circulation path and between the processing gas supply port to the processing space and the decomposition processing unit, and adsorbs moisture and carbon dioxide from the exhaust gas. Item 3. The substrate processing apparatus according to Item 2.   The removal section has a plurality of adsorption towers, and while performing adsorption treatment of moisture and carbon dioxide by one adsorption tower, the remaining adsorption towers are subjected to regeneration treatment for restoring the adsorption performance of moisture and carbon dioxide. The substrate processing apparatus of Claim 3 performed with respect to it.   The substrate processing apparatus according to claim 1, wherein the inert gas supplied by the gas supply unit is an unused gas. Electrons irradiated with the electron beam by moving the substrate relative to the electron beam generating means while irradiating the surface of the substrate disposed in the processing space of the processing chamber with the electron beam from the electron beam generating means. In a substrate processing method of scanning a beam irradiation region and performing a predetermined process on the substrate surface,
While performing the electron beam irradiation, an inert gas is supplied to the electron beam irradiation region, and a contaminant generated by the electron beam irradiation to the substrate is exhausted around the electron beam irradiation region. Is exhausted from the processing chamber as an exhaust gas together with the inert gas, and a processing gas obtained by removing the contaminants from the exhaust gas is supplied to the processing space.

Images