JP2015084387A - Substrate processing apparatus and substrate processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate processing device which allows for uniform processing of a substrate in the in-plane thereof by using light emission of plasma, and to provide a substrate processing method.SOLUTION: A light-emitting panel 5, as a light irradiation unit, internally has a plurality of discharge cells 40, a long discharge electrode 47 provided corresponding to the discharge cells 40, respectively, and a plurality of long address electrodes 53 provided in a direction orthogonal to the discharge electrode 47. Interior of each discharge cell 40 is a plasma generation space for generating plasma. The light-emitting panel 5 generates the ultraviolet rays by a plasma generated in the discharge cell 40, and the processing space S1 in a processing container 1 is irradiated with the ultraviolet rays.

Description

  The present invention relates to a substrate processing apparatus and a substrate processing method for processing a substrate using plasma emission.

  In the manufacturing process of a semiconductor device, a flat panel display, and the like, various processes such as a film forming process, an etching process, an annealing process, a modifying process, a curing process, and an ashing process are performed on the substrate. As a substrate processing apparatus used for these processes, an apparatus using ultraviolet rays is known.

  For example, Patent Document 1 discloses an atomic layer growth apparatus including a plasma generation chamber provided above a film formation chamber of a film formation container, and an ultraviolet ray transmitting plate that transmits ultraviolet light so as to separate the plasma generation chamber and the film formation chamber. Proposed.

JP 2009-194018 A (FIG. 1 etc.)

  The substrate processing apparatus disclosed in Patent Literature 1 has a plasma generation space wider than the substrate surface above the substrate, and generates plasma there and uses the emitted ultraviolet light for substrate processing. However, when generating plasma in a wide plasma generation space, it is difficult to generate uniform plasma, and it is known that a distribution occurs in the plasma density. When the plasma density is distributed, the intensity of the UV light becomes uneven and the UV light dose is biased in the surface of the substrate or directly above the substrate, or the UV light itself becomes unstable. There was a problem of doing.

  In addition, with the recent increase in size of substrates, it is becoming increasingly difficult to maintain the uniformity of processing within the substrate surface.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a substrate processing apparatus and a substrate processing method that can perform uniform processing in a plane of a substrate by using light emission of plasma.

  The substrate processing apparatus of the present invention includes a processing container having a processing space for processing a substrate, a substrate holding part for holding the substrate in the processing container, and light for processing the substrate toward the processing space. A light irradiation unit for irradiating. In the substrate processing apparatus of the present invention, the light irradiation units are arranged in parallel with each other, and are provided corresponding to each of the plurality of discharge cells formed so as to be able to introduce and exhaust gas. A discharge electrode.

  In the substrate processing apparatus of the present invention, the light irradiation unit may further include a plurality of address electrodes provided in a direction orthogonal to the discharge electrodes.

  In the substrate processing apparatus of the present invention, the light irradiation unit may be provided in an upper part of the processing container so as to face the substrate held by the substrate holding unit with the processing space being separated.

  In the substrate processing apparatus of the present invention, the light irradiation unit is disposed in common with the plurality of discharge cells, and is disposed opposite to the bottom plate and provided in common with the plurality of discharge cells. It may have a top plate and a plurality of partition walls that are interposed between the bottom plate and the top plate and separate the discharge cells adjacent to each other.

  In the substrate processing apparatus of the present invention, the bottom plate, the top plate, and the partition may be made of a dielectric material.

  In the substrate processing apparatus of the present invention, at least the bottom plate may be formed of a light transmissive material.

  The substrate processing apparatus of this invention may be provided with the light reflection part which reflects light in the outer surface of the said top plate.

  The substrate processing apparatus of this invention may be provided with the light-diffusion part which scatters and diffuses light in the outer surface of the said baseplate.

  In the substrate processing apparatus of the present invention, the discharge cell includes a first gas introduction unit that introduces a plasma generation gas into a plasma generation space that generates plasma, and a first exhaust unit that exhausts the plasma generation space. , May be provided.

  The substrate processing apparatus of this invention may have the 2nd gas introduction part which introduces the process gas which processes the said board | substrate under the said light irradiation unit.

  In the substrate processing apparatus of the present invention, the plasma light generated in the discharge cell may be vacuum ultraviolet light.

  In the substrate processing method of the present invention, a substrate is processed by any one of the above-described substrate processing apparatuses.

  According to the substrate processing apparatus and the substrate processing method of the present invention, uniform processing can be performed in the plane of the substrate by utilizing the light emission of plasma generated by a plurality of discharge cells formed in parallel to each other. .

It is sectional drawing which shows schematic structure of the substrate processing apparatus of the 1st Embodiment of this invention. It is sectional drawing which shows the principal part of the substrate processing apparatus of FIG. It is sectional drawing which shows another principal part of the substrate processing apparatus of FIG. It is an external appearance perspective view of the light emission panel used for the substrate processing apparatus of FIG. It is explanatory drawing which shows the internal structure of a light emission panel. It is drawing which illustrates typically the principle of the light irradiation by a light emission panel. FIG. 7 is a diagram schematically illustrating the principle of light irradiation by the light-emitting panel, following FIG. 6. FIG. 8 is a diagram schematically illustrating the principle of light irradiation by the light-emitting panel, following FIG. 7. It is drawing explaining an example of the voltage application system to a discharge cell. It is drawing explaining another example of the voltage application system to a discharge cell. It is drawing explaining the further another example of the voltage application system to a discharge cell. It is drawing explaining the further another example of the voltage application system to a discharge cell. It is explanatory drawing of the preferable aspect of a light emission panel. It is explanatory drawing of another preferable aspect of a light emission panel.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
FIG. 1 is a cross-sectional view showing a schematic configuration of a single wafer processing apparatus 100 according to the first embodiment of the present invention. 2 and 3 are enlarged cross-sectional views showing the main part of the substrate processing apparatus 100. FIG. The substrate processing apparatus 100 according to the present embodiment performs various processes such as a film forming process, an etching process, an annealing process, a modification process, a curing process, and an ashing process on the substrate S that is an object to be processed. It is a processing device. Here, examples of the substrate S include a semiconductor wafer, a liquid crystal display, a flat panel display (FPD) substrate typified by an organic EL display, and a solar cell substrate.

  A substrate processing apparatus 100 according to the present embodiment includes a processing container 1 having a processing space S1 for processing a substrate S, a mounting table 3 as a substrate holding unit that holds the substrate S in the processing container 1, and a processing container. 1 is provided with a light-emitting panel 5 as a light irradiation unit that irradiates ultraviolet rays toward the processing space S1 inside 1, and a control unit 7.

<Processing container>
The processing container 1 is a pressure-resistant container that can be evacuated. The processing container 1 is formed of a metal material. As a material for forming the processing container 1, for example, aluminum, aluminum alloy, stainless steel, or the like is used. The processing container 1 includes a bottom wall 11, a cylindrical side wall 13, and a ceiling portion 15. Note that the overall shape of the processing container 1 is not limited to a cylindrical shape, and may be, for example, a rectangular tube shape.

  The bottom wall 11 is provided with one or a plurality of exhaust ports 11a. In FIG. 1, two exhaust ports 11a are illustrated. The exhaust port 11 a is connected to the exhaust device 19 through the exhaust pipe 17. By driving the exhaust device 19, the inside of the processing vessel 1 can be evacuated to a predetermined pressure, for example, from atmospheric pressure to a pressure of about 0.1 Pa.

  On the side wall 13, a loading / unloading port 13 a for loading and unloading the substrate S into and from the processing container 1 is provided. A gate valve GV is provided at the carry-in / out port 13a. The gate valve GV has a function of opening and closing the loading / unloading port 13a, and hermetically seals the loading / unloading port 13a in the closed state, and enables the transfer of the substrate S between the processing container 1 and the outside in the opened state.

  The side wall 13 is provided with a gas introduction part 13 b for introducing a gas into the processing container 1. The gas introduction part 13 b is a flow path formed inside the side wall 13. The gas introduction unit 13 b is connected to the gas supply device 27. In addition, you may provide the gas introduction part 13b in positions other than the side wall 13, for example, the ceiling part 15 grade | etc.,.

  The ceiling part 15 is disposed in contact with the upper end of the side wall 13 and also functions as a lid part for opening and closing the processing container 1. Moreover, the ceiling part 15 has the recessed part 15a to which the light emission panel 5 is mounted | worn.

<Mounting table>
Inside the processing container 1, a mounting table 3 as a substrate holding unit that holds the substrate S is provided. The mounting table 3 is fixed to the bottom wall 11. Although not shown, the mounting table 3 has a mechanism for moving the substrate S up and down, such as a lift pin. Accordingly, the height position of the substrate S is set between the transfer position for transferring the substrate S to and from the external transfer device and the processing position for placing the substrate S on the mounting table 3 and performing a predetermined process. Can be adjusted. In addition, as a board | substrate holding | maintenance part, not only a mounting base but the support apparatus provided with the support pin etc. which contact the back surface of the board | substrate S in multiple places can also be used, for example. Further, the substrate holding unit may include a temperature adjusting unit for heating or cooling the substrate S. Further, the substrate holding unit may include means for applying a bias voltage for drawing charged particles such as ions generated by decomposition of the processing gas into the substrate S.

<Exhaust device>
The substrate processing apparatus 100 according to the present embodiment further includes an exhaust device 19. The exhaust device 19 may not be a component part of the substrate processing apparatus 100 but may be an external device different from the substrate processing apparatus 100. The exhaust device 19 has, for example, a vacuum pump such as a turbo molecular pump or a dry pump. The substrate processing apparatus 100 further includes an exhaust pipe 17 connecting the exhaust port 11a and the exhaust apparatus 19, an APC (Adaptive Pressure Control) valve 23 provided in the middle of the exhaust pipe 17, an opening / closing valve 25, and the like. Yes. The APC valve 23 is connected to a pressure gauge (not shown) for measuring the pressure in the processing container 1. By operating the vacuum pump of the exhaust device 19 and adjusting the opening of the APC valve 23, the internal space of the processing container 1 can be evacuated to a predetermined degree of vacuum. The APC valve 23 includes one master valve and a plurality of slave valves, and each slave valve operates in conjunction with the master valve.

<Gas supply mechanism>
The substrate processing apparatus 100 according to the present embodiment includes a gas supply device 27 that supplies gas into the processing container 1. The gas supply device 27 may not be a component part of the substrate processing apparatus 100 but may be an external device different from the substrate processing apparatus 100.

  The gas supply device 27 is connected to the gas supply source 29 that holds one or more kinds of gas, and the gas supply source 29 and the gas introduction unit 13b, and supplies one or more gas to the gas introduction unit 13b. Piping 31A (only one is shown). The gas supply device 27 includes a mass flow controller (MFC) 33A for controlling the gas flow rate and a plurality of opening / closing valves 35A (only two shown) in the middle of the pipe 31A. The flow rate of the gas introduced into the processing container 1 from the gas introduction part 13b is controlled by the mass flow controller 33A and the opening / closing valve 35A. The gas supplied from the gas supply source 29 can be selected according to the purpose of processing, such as a film forming gas, an etching gas, and a purge gas.

(Shower plate)
The shower plate 37 is supported on the side wall 13 by a fixture (not shown). The shower plate 37 is arranged in parallel to the light emitting panel 5 and opposed to the lower surface of the light emitting panel 5 and has a plurality of through holes 37a. A space S2 between the shower plate 37 and the light emitting panel 5 is a gas diffusion space for diffusing the processing gas supplied from the gas introduction part 13b. The gas ejection hole of the gas introduction part 13b is formed at a position facing the space S2. The processing gas introduced from the gas introduction part 13b into the space S2 above the shower plate 37 diffuses through the space S2, and is supplied to the processing space S1 below the shower plate 37 through the plurality of through holes 37a. .

  The shower plate 37 is formed of a light-transmitting material such as quartz. The upper surface of the shower plate 37 may have an uneven shape, for example, in order to suppress reflection of light toward the light emitting panel 5. Further, the lower surface of the shower plate 37 may have a diffusion surface processed into a prism shape, for example, in order to diffuse light transmitted through the shower plate 37.

<Light irradiation unit>
FIG. 4 is a perspective view showing an appearance of the light emitting panel 5 as a light irradiation unit. FIG. 5 is a partial perspective view showing the internal structure of the light-emitting panel 5. The light emitting panel 5 has a plurality of discharge cells 40 therein. The light emitting panel 5 generates ultraviolet rays by the plasma generated in the discharge cell 40 and irradiates the processing space S <b> 1 inside the processing container 1 with the ultraviolet rays. The light emitting panel 5 has a flat plate shape as a whole, and is mounted so as to be fitted into the concave portion 15a of the ceiling portion 15 by fixing means such as a screw (not shown). The planar shape of the light emitting panel 5 can be, for example, a circle or a polygon according to the shape of the substrate S. As shown in FIGS. 2 and 3, the light emitting panel 5 and the ceiling portion 15 are hermetically sealed by a plurality of seal members 39 (only one is shown). In addition, arrangement | positioning of the sealing member 39 is not restricted to the aspect of illustration. The light emitting panel 5 is disposed in parallel to the processing surface (that is, the upper surface) of the substrate S held on the mounting table 3 and at a position directly above the substrate S via the processing space S1.

  In the present embodiment, the light-emitting panel 5 has a thin cubic shape, and includes a bottom plate 41, a top plate 43 disposed to face the bottom plate 41, and a plurality of partition walls interposed between the bottom plate 41 and the top plate 43. 45 and a side wall 46 that closes the side portion. The bottom plate 41, the top plate 43, the partition walls 45, and the side walls 46 form a plurality of long discharge cells 40. Each discharge cell 40 has a plasma generation space for generating plasma. The width of the discharge cells 40 is not particularly limited, but can be, for example, in the range of 0.5 mm to 10 mm, and the interval between adjacent discharge cells 40 (that is, the thickness of the barrier ribs 45) is, for example, 1 mm. It can be in the range of ~ 15 mm.

  The light emitting panel 5 includes a long discharge electrode 47 provided corresponding to each discharge cell 40 and a plurality of long address electrodes provided in a direction orthogonal to the discharge electrode 47. 53.

  The bottom plate 41 and the top plate 43 are both provided in common for the plurality of discharge cells 40. The bottom plate 41 and the top plate 43 are provided in parallel to each other. The barrier ribs 45 serve to separate the two discharge cells 40 adjacent to each other.

  The bottom plate 41, the top plate 43, and the partition 45 are made of a dielectric material that transmits electromagnetic waves. Further, at least the bottom plate 41 on the side facing the space S2 and the processing space S1 is formed of a light transmissive material. As a material of the bottom plate 41, the top plate 43, and the partition wall 45, for example, quartz is preferable. The bottom plate 41, the top plate 43, and the partition wall 45 have a laminated structure that is integrated by a bonding method in which the refractive index does not change on the bonding surface. Here, as a bonding method in which the refractive index does not change on the bonding surface, for example, diffusion bonding can be mentioned.

  The discharge electrode 47 is provided in parallel to the longitudinal direction of the discharge cell 40. In the present embodiment, the discharge electrode 47 includes a pair of electrode lines 47A and an electrode line 47B. The discharge electrode 47 is long and substantially the same length as the discharge cell 40. The discharge electrode 47 is connected to a power source 51 outside the processing container 1 through a power supply line 49. In FIG. 4, connection terminal portions between the discharge electrode 47 and the power supply line 49 are denoted by reference numerals 49A and 49B.

  The discharge electrode 47 preferably has optical transparency, and can be formed of a transparent electrode material such as ITO (indium tin oxide), ZnO (zinc oxide), or SnO (tin oxide). The discharge electrode 47 may be a metal electrode material (copper, nickel, etc.). In this case, it is preferable to increase the width of the discharge cells 40 or increase the interval between adjacent discharge cells 40 so as to increase the light transmission area.

  A plurality of address electrodes 53 are provided in a direction orthogonal to the discharge electrode 47. The plurality of address electrodes 53 are formed in a long shape so as to intersect with the plurality of discharge electrodes 47 in a grid pattern. The address electrode 53 is connected to a power source 57 outside the processing container 1 via a power supply line 55. In FIG. 4, connection terminal portions between the address electrode 53 and the power supply line 55 are denoted by reference numerals 55A and 55B.

  Further, each discharge cell 40 of the light emitting panel 5 is provided with a gas introduction part 61 for introducing a gas for plasma generation into the plasma generation space and an exhaust part 63 for exhausting the plasma generation space. A gas introduction path 65 is connected to the gas introduction part 61 of each discharge cell 40. An exhaust path 67 is connected to the exhaust part 63 of each discharge cell 40. The plurality of gas introduction paths 65 and the plurality of exhaust paths 67 are all gas flow paths provided in the ceiling portion 15. The same number of gas introduction paths 65 and exhaust paths 67 as the discharge cells 40 are formed. A pipe 31 </ b> B from the gas supply device 27 is connected to the gas introduction path 65. A gas supply device other than the gas supply device 27 may be connected to the gas introduction path 65. Further, instead of providing the gas introduction part 61 and the exhaust part 63 separately, a single air supply / exhaust part that also serves as these may be provided.

  The gas supply device 27 connects a gas supply source 29 that holds one or more kinds of plasma generation gas, the gas supply source 29 and the gas introduction path 65, and supplies the plasma generation gas to the gas introduction path 65. One or a plurality of pipes 31B (only one is shown) is provided. Further, the gas supply device 27 includes a mass flow controller (MFC) 33B for controlling the gas flow rate and a plurality of opening / closing valves 35B (only two are shown) in the middle of the pipe 31B. The flow rate of the plasma generating gas introduced into each discharge cell 40 from the gas introduction unit 61 is controlled by the mass flow controller 33B and the open / close valve 35B. The plasma generating gas supplied from the gas supply source 29 to each discharge cell 40 is a gas that generates plasma that emits vacuum ultraviolet light. For example, Ar, Kr, Xe, Ne, D (deuterium), Hg (Mercury; 185 nm / 6.5 eV), CO (carbon dioxide; 172.85 nm / 7.2 eV), and the like. Among these, Xe (172 nm / 7.2 eV), Ar (126 nm / 9.8 eV), and Kr (146 nm / 8.5 eV) are preferable (in parentheses indicate the emission center wavelength and photon energy). In addition, the plasma generating gas can include an inert gas such as nitrogen as a dilution gas.

  The exhaust path 67 is connected to the exhaust device 19 via the exhaust pipe 69. Therefore, by operating the exhaust device 19, the inside of the discharge cell 40 can be depressurized and adjusted to a predetermined pressure. Although illustration and description are omitted, the exhaust pipe 69 is provided with valves such as an APC valve and an open / close valve as well as the exhaust pipe 17 connected to the exhaust port 11a of the bottom wall 11 of the processing vessel 1 and the discharge electrode. Can be provided. In FIG. 1 and the like, only the open / close valve 70 is representatively shown. Further, the exhaust passage 67 may be connected to an exhaust device different from the exhaust device 19.

<Purge gas introduction mechanism>
A gap 71 is formed between the ceiling 15 and the light emitting panel 5. The gap portion 71 has an action of eliminating distortion due to a difference in coefficient of thermal expansion between the metallic ceiling portion 15 and the discharge cell 40 made of a dielectric material.

  In the center of the ceiling portion 15, a purge gas introduction portion 73 is provided for introducing a purge gas into the gap portion 71 between the light emitting panel 5 and the ceiling portion 15. The purge gas introduction part 73 penetrates the ceiling part 15 and communicates with the gap part 71. The purge gas introduction unit 73 is connected to the gas supply device 27. Note that a gas supply device different from the gas supply device 27 may be connected to the purge gas introduction unit 73.

  In the present embodiment, the gas supply source 29 of the gas supply device 27 has a purge gas storage unit (not shown) that holds the purge gas. The gas supply device 27 includes a pipe 31 </ b> C that connects the gas supply source 29 and the purge gas introduction unit 73 and supplies the purge gas to the purge gas introduction unit 73. Further, the gas supply device 27 includes a mass flow controller (MFC) 33C for controlling the gas flow rate and a plurality of opening / closing valves 35C (only two are shown) in the middle of the pipe 31C. The flow rate of the purge gas introduced into the gap 71 from the purge gas introduction part 73 is controlled by the mass flow controller 33C and the open / close valve 35C. As the purge gas supplied from the gas supply source 29 to the gap 71, for example, an inert gas such as nitrogen can be used.

  Further, in order to evacuate the gap 71 between the light emitting panel 5 and the ceiling 15 under reduced pressure, a pipe connected to the exhaust device 19 or other exhaust equipment may be provided in communication with the gap 71. By holding the gap 71 in a vacuum, the pressure applied to the light emitting panel 5 when the inside of the processing container 1 is evacuated can be reduced.

<Control unit>
As shown in FIG. 1, each component of the substrate processing apparatus 100 is connected to and controlled by the control unit 7. The control unit 7 includes a controller 81 including a CPU, a user interface 82, and a storage unit 83. The controller 81 has a computer function, and controls each component in the substrate processing apparatus 100 in an integrated manner. The user interface 82 includes a keyboard that allows a process manager to input commands to manage the substrate processing apparatus 100, a display that visualizes and displays the operating status of the substrate processing apparatus 100, and the like. The storage unit 83 stores a recipe in which a control program (software) for implementing various processes executed by the substrate processing apparatus 100 under the control of the controller 81 and processing condition data are recorded. The user interface 82 and the storage unit 83 are connected to the controller 81.

  Then, if necessary, an arbitrary recipe is called from the storage unit 83 by an instruction from the user interface 82 and is executed by the controller 81, so that desired processing in the substrate processing apparatus 100 is performed under the control of the controller 81. Is done. At this time, the control unit 7 selects, for example, an arbitrary discharge electrode 47 from the power source 51 and the magnitude of the applied voltage, or selects an arbitrary address electrode 53 from the power source 57 and the magnitude of the applied voltage. By adjusting the height, it is possible to precisely control the amount of emitted light and the distribution of the amount of light within the surface of the light-emitting panel 5. Recipes such as the control program and processing condition data can be stored in a computer-readable storage medium such as a CD-ROM, a hard disk, a flexible disk, or a flash memory. Alternatively, it can be transmitted from other devices as needed via, for example, a dedicated line and used online.

  Next, the principle of light irradiation by the light emitting panel 5 will be described with reference to FIGS. 6 to 8 schematically show the inside of the two discharge cells 40. For convenience of explanation, the left side of the drawing is distinguished as the discharge cell 40A and the right side as the discharge cell 40B. FIG. 6 shows a state before discharge. FIG. 7 shows a state where the discharge is performed in the discharge cell 40A on one side and the plasma P is generated in the plasma generation space. FIG. 8 shows a state in which discharge is performed in a discharge cell 40B different from FIG. 7 and plasma P is generated in the plasma generation space.

  FIG. 6 is a preparatory stage before discharge. First, the exhaust device 19 is used to evacuate the discharge cells 40A and 40B to a predetermined pressure, and the plasma generating gas is supplied from the gas supply device 27 through the pipe 31B, the gas introduction path 65, and the gas introduction section 61. It is introduced into the discharge cell 40.

  Next, in order to generate plasma in the discharge cell 40A, voltages are respectively applied to the address electrode 53 and the discharge electrode 47 corresponding to the discharge cell 40A, thereby generating a small discharge (address discharge) in the discharge cell 40A. . Using this address discharge as a fire, a luminescent discharge is then generated by applying a DC voltage or an AC voltage between the pair of electrode lines 47A and 47B of the discharge electrode 47 corresponding to the discharge cell 40A, as shown in FIG. Then, plasma P of plasma generating gas is generated in the discharge cell 40A. The plasma P in the discharge cell 40A emits vacuum ultraviolet light 200 having a wavelength of 200 nm or less. The generated vacuum ultraviolet light 200 is radiated toward the processing space S <b> 1 in the processing container 1 through the bottom plate 41. The plasma P and the vacuum ultraviolet light 200 disappear when the application of voltage to the discharge electrode 47 corresponding to the discharge cell 40A is stopped. Note that the address discharge may be omitted, and a light emission discharge may be generated by directly applying a voltage between the electrode lines 47A and 47B.

  Next, in order to generate plasma in the discharge cell 40B, a voltage is applied to the address electrode 53 and the discharge electrode 47 corresponding to the discharge cell 40B, and a small discharge (address discharge) is generated in the discharge cell 40B. Let Using this address discharge as a seed fire, a light emission discharge is then generated by applying a DC voltage or an AC voltage between the pair of electrode lines 47A and 47B of the discharge electrode 47 corresponding to the discharge cell 40B, as shown in FIG. Then, plasma P of plasma generating gas is generated in the discharge cell 40B. The plasma P in the discharge cell 40B emits vacuum ultraviolet light 200 having a wavelength of 200 nm or less. The generated vacuum ultraviolet light 200 is radiated toward the processing space S <b> 1 in the processing container 1 through the bottom plate 41. The plasma P and the vacuum ultraviolet light 200 disappear when the application of voltage to the discharge electrode 47 corresponding to the discharge cell 40B is stopped. Note that the address discharge may be omitted, and a light emission discharge may be generated by directly applying a voltage between the electrode lines 47A and 47B.

  As described above, the light-emitting panel 5 can select any discharge cell 40 and generate the plasma P by switching the applied voltage to the address electrode 53 and the discharge electrode 47 arranged in a grid pattern. . Of course, it is also possible to generate the plasma P simultaneously in all the discharge cells 40 and irradiate the vacuum ultraviolet light 200 from the entire area of the bottom plate 41 of the light emitting panel 5 toward the processing space S1 in the processing container 1. Further, the type of plasma generating gas to be introduced can be changed in the discharge cell 40A and the discharge cell 40B.

  Further, the light-emitting panel 5 can control the voltage applied to the address electrode 53 and the discharge electrode 47 so that the light emission energy of the plasma P is strong or weak at a predetermined intersection of the electrodes. Therefore, by using the light emitting panel 5, not only can the vacuum ultraviolet light 200 be uniformly irradiated in the plane of the substrate S, but also the amount of the vacuum ultraviolet light 200 can be locally increased or decreased to increase the amount of the vacuum ultraviolet light 200 in the plane of the substrate S. It is also possible to change the processing content, such as the film forming speed and the heating temperature.

  Here, with reference to FIGS. 9 to 12, an example of the voltage application method to the discharge cell 40 will be described. 9 to 12 schematically show typical modes of voltage application to the plasma generation space of the discharge cell 40.

  9 and 10 show a parallel electrode system in which a pair of electrode lines 47A and 47B as discharge electrodes 47 are arranged on a bottom plate 41 forming the discharge cell 40. FIG. FIG. 9 shows a state in which the plasma P is generated by applying a direct-current voltage (DC) between the pair of electrode wires 47A and 47B in a state where the plasma generation space is filled with the plasma generation gas. On the other hand, FIG. 10 shows a state in which the plasma P is generated by applying an alternating voltage (AC) between the pair of electrode wires 47A and 47B in a state where the plasma generation space is filled with the plasma generation gas. 9 and 10 are each a three-electrode system using the address electrode 53.

  11 and 12 show a counter electrode system in which a pair of discharge electrodes 47 are arranged to face each other on the bottom plate 41 and the top plate 43 of the discharge cell 40 facing each other. That is, the electrode wire 47C is disposed on the bottom plate 41, and the electrode wire 47D is disposed on the top plate 43. FIG. 11 shows a state in which plasma P is generated by applying a direct-current voltage (DC) between the pair of electrode wires 47C and 47D in a state where the plasma generation space is filled with the plasma generation gas. On the other hand, FIG. 12 shows a state in which the plasma P is generated by applying an alternating voltage (AC) between the pair of electrode wires 47C and 47D in a state where the plasma generation space is filled with the plasma generation gas. 11 and 12 show a two-electrode system in which neither of the address electrodes 53 is used. As described above, the light emitting panel 5 may not include the address electrode 53.

  In the substrate processing apparatus 100 of FIG. 1, the light emitting panel 5 exemplifies the three-electrode / parallel electrode system shown in FIG. 9 or 10, but adopts the two-electrode / counter-electrode system shown in FIG. 11 or FIG. 12. May be.

  Next, with reference to FIGS. 13 and 14, a preferable aspect of the light-emitting panel 5 used in the substrate processing apparatus 100 of the present embodiment will be described. FIG. 13 shows an example in which the light reflecting portion 91 is provided on the top surface of the top plate 43 of the light-emitting panel 5 (that is, the outer surface opposite to the surface facing the plasma generation space in the discharge cell 40 of the top plate 43). ing. The light reflecting portion 91 reflects light, which is about to escape above the top plate 43, of the vacuum ultraviolet light 200 emitted from the plasma P toward the bottom plate 41 side. The light reflecting portion 91 can be formed of a member or thin film that reflects light. By providing the light reflecting portion 91, the utilization efficiency of the vacuum ultraviolet light 200 can be increased and the luminance can be improved. In this case, the light reflecting portion 91 can be formed by printing a material having a high optical reflectance such as titanium dioxide or barium sulfate on the top plate 43 as a predetermined pattern-like thin film by a method such as a screen printing method. . The light reflecting portion 91 may be formed by providing a thin film obtained by finely foaming a transparent resin such as polyethylene terephthalate or polycarbonate on the top surface of the top plate 43. The light reflecting portion 91 can also be formed by bonding a sheet of a light reflecting material such as an aluminum foil to the upper surface of the top plate 43, for example.

  FIG. 14 shows an example in which a light diffusing portion 93 is provided on the outer lower surface of the bottom plate 41 of the light emitting panel 5 (that is, the outer surface of the bottom plate 41 opposite to the surface facing the plasma generation space in the discharge cell 40). Yes. The light diffusing unit 93 scatters the light transmitted through the bottom plate 41 and diffuses it into the processing space S1. The light diffusing unit 93 can diffuse the vacuum ultraviolet light 200 over the entire processing space S1. The light diffusion portion 93 can be formed by a diffusion surface obtained by processing the lower surface of the bottom plate 41 into a prism shape, for example.

  The light emitting panel 5 can be provided with both the light reflecting portion 91 and the light diffusing portion 93.

[Substrate processing procedure]
A substrate processing procedure using the substrate processing apparatus 100 configured as described above will be described. Here, a case where a silicon thin film or a silicon nitride film is formed on the substrate S by the CVD (chemical vapor deposition) method using the vacuum ultraviolet light 200 will be described as an example.

  First, the gate valve GV is opened, and the substrate S is transferred to the mounting table 3 of the substrate processing apparatus 100 by an external transfer device (not shown).

  Next, the gate valve GV is closed and the exhaust device 19 is operated to evacuate the processing container 1 under reduced pressure. Then, while monitoring the pressure in the processing container 1 with a pressure gauge (not shown), the opening degree of the APC valve 23 is controlled to reduce the pressure to a predetermined degree of vacuum.

  Next, the exhaust device 19 is used to evacuate each discharge cell 40 to a predetermined pressure. Then, a plasma generating gas is introduced into the discharge cell 40 from the gas supply device 27 through the pipe 31 </ b> B, the gas introduction path 65, and the gas introduction unit 61. After introducing the plasma generating gas, each discharge cell 40 is sealed in a state in which the plasma generating gas is filled by closing the open / close valve 35B and the open / close valve 70.

  Next, in order to determine the position where plasma is generated, an ignition voltage (300 to 400 V) is applied to each of the address electrode 53 and the discharge electrode 47 to cause local discharge (address discharge). Using this address discharge as a fire, a discharge sustaining voltage (DC voltage or AC voltage of 150 to 200 V) is applied from the power source 51 between the pair of electrode lines 47A and 47B of the discharge electrode 47 corresponding to the selected discharge cell 40. . As a result, a light emitting discharge is generated in the discharge cell 40, and the plasma generating gas is turned into plasma. The generated plasma P emits vacuum ultraviolet light 200 having a wavelength of 200 nm or less. The generated vacuum ultraviolet light 200 is radiated toward the processing space S <b> 1 in the processing container 1 through the bottom plate 41. Further, the plasma in the discharge cell 40 can be controlled by applying a control voltage (50 to 150 V) to the address electrode 53.

  Next, for example, silane gas is introduced as a processing gas into the space S2 above the shower plate 37 from the gas inlet 13b. The silane gas introduced into the space S2 from the gas introduction part 13b diffuses immediately below the light emitting panel 5 and is supplied to the processing space S1 below the shower plate 37 through the plurality of through holes 37a. In the space S2 above the shower plate 37, the vacuum ultraviolet light 200 can be efficiently irradiated to the silane gas. Further, since the vacuum ultraviolet light 200 emitted from the light emitting panel 5 passes through the shower plate 37 and is emitted to the processing space S1 in the processing container 1, the vacuum ultraviolet light 200 is irradiated to the silane gas also in the processing space S1. Is done. The silane gas is decomposed by the light energy of the vacuum ultraviolet light 200, and a silane decomposition product can be deposited on the substrate S. When the silane decomposition product reaches a predetermined thickness, the supply of silane gas is stopped. Thereafter, by continuing the irradiation with the vacuum ultraviolet light 200, hydrogen atoms are desorbed from the silane decomposition product, and a silicon thin film can be formed.

  Next, power supply from the power source 51 to the discharge electrode 47 is stopped, and the plasma P and the vacuum ultraviolet light 200 are extinguished. Further, the exhaust device 19 is stopped, and the inside of the processing container 1 is increased to a predetermined pressure. Thereafter, the gate valve GV is opened, and the substrate S is unloaded from the processing container 1 by an external transfer device (not shown). With the above procedure, the silicon thin film deposition process on one substrate S is completed.

  After the silicon thin film is formed by the above method, the silicon nitride film can also be formed by introducing ammonia gas from the gas introducing portion 13b into the space S2 while continuing the irradiation with the vacuum ultraviolet light 200. That is, the ammonia gas can be decomposed by the vacuum ultraviolet light 200, and the silicon thin film on the substrate S can be nitrided by the generated ammonia decomposition product to be modified into a silicon nitride film.

  As another method for forming a silicon nitride film, silane gas and ammonia gas may be simultaneously introduced into the space S2 from the gas introduction part 13b while irradiating the vacuum ultraviolet light 200 with the light emitting panel 5. In this case, decomposition of silane gas and ammonia gas and generation of silicon nitride occur simultaneously, and a silicon nitride film can be deposited on the substrate S.

  As described above, since the substrate processing apparatus 100 according to the present embodiment includes the light emitting panel 5, the vacuum ultraviolet light 200 can be evenly irradiated toward the processing space S1 and the substrate S. Therefore, it is possible to perform uniform processing within the surface of the substrate S without causing non-uniformity of processing within the surface of the substrate S due to the deviation of the plasma density, which is a problem in the conventional plasma processing apparatus. . Further, it is possible to easily cope with an increase in the size of the substrate S.

  Moreover, in the substrate processing apparatus 100 of this Embodiment, since the unitized light emission panel 5 is used as a light irradiation source, the target substrate processing can be performed with a simple apparatus configuration.

  In the substrate processing apparatus 100 of the present embodiment, the light emitting panel 5 is configured to irradiate the vacuum ultraviolet light 200. However, instead of the vacuum ultraviolet light 200, for example, red is selected by selecting the type of plasma generating gas. Heat treatment or the like can be performed by irradiating with external light. Moreover, the plasma generation gas introduced into each discharge cell 40 is not limited to the same type, and may be a different type. Therefore, it is possible to emit light having different wavelengths according to the type of the processing gas in the plurality of discharge cells 40.

  As mentioned above, although embodiment of this invention was described in detail for the purpose of illustration, this invention is not restrict | limited to the said embodiment, A various deformation | transformation is possible. For example, in the above-described embodiment, as a specific example of the substrate processing, the film formation of the silicon thin film and the silicon nitride film by the CVD method using the vacuum ultraviolet light 200 is given as an example, but the substrate processing apparatus of the present invention is, for example, It can also be used to form amorphous silicon films for solar cells, silicon oxide films, and the like.

Further, the substrate processing apparatus of the present invention is not limited to the film forming process, but includes an etching process, an annealing process, a modification process (for example, carbon removal in the organic film, high oxygen concentration by desorption of hydrogen in the film, etc.), curing. processing (e.g., a polymer produced by photochemical reaction), ashing, cleaning processing in the processing chamber (e.g., decomposition removal process NF ₃ and organosiloxane compounds, such as oxidation removal process impurities), a silicon substrate or a glass substrate impurities It can be applied to various uses such as substrate pretreatment such as removal.

  DESCRIPTION OF SYMBOLS 1 ... Processing container, 3 ... Mounting stand, 5 ... Light emission panel, 7 ... Control part, 11 ... Bottom wall, 13 ... Side wall, 13a ... Carry-in / out port, 15 ... Ceiling part, 17 ... Exhaust pipe, 19 ... Exhaust device, 23 APC valve, 27 ... Gas supply device, 29 ... Gas supply source, 31A, 31B, 31C ... Piping, 33A, 33B, 33C ... Mass flow controller (MFC), 35A, 35B, 35C ... Open / close valve, 37 ... Shower plate, DESCRIPTION OF SYMBOLS 40 ... Discharge cell, 65 ... Gas introduction path, 67 ... Exhaust path, 69 ... Exhaust pipe, 81 ... Controller, 82 ... User interface, 83 ... Memory | storage part, 100 ... Substrate processing apparatus, S ... Substrate, S1 ... Processing space, S2 ... Space, GV ... Gate valve

Claims (12)

A processing container having a processing space for processing a substrate;
A substrate holder for holding the substrate in the processing container;
A light irradiation unit for irradiating light for processing the substrate toward the processing space;
The light irradiation unit comprises:
A plurality of discharge cells arranged in parallel to each other and capable of introducing and exhausting gas;
A discharge electrode provided corresponding to each of the discharge cells;
A substrate processing apparatus comprising:   The substrate processing apparatus according to claim 1, wherein the light irradiation unit further includes a plurality of address electrodes provided in a direction orthogonal to the discharge electrodes.   3. The substrate processing apparatus according to claim 1, wherein the light irradiation unit is provided to face the substrate held by the substrate holding unit across the processing space at an upper portion of the processing container. The light irradiation unit is:
A bottom plate provided in common to the plurality of discharge cells;
A top plate disposed opposite to the bottom plate and provided in common to the plurality of discharge cells,
A plurality of barrier ribs interposed between the bottom plate and the top plate and separating the discharge cells adjacent to each other;
The substrate processing apparatus of any one of Claim 1 to 3 which has these.   The substrate processing apparatus according to claim 4, wherein the bottom plate, the top plate, and the partition are formed of a dielectric material.   The substrate processing apparatus according to claim 4, wherein at least the bottom plate is made of a light transmissive material.   The substrate processing apparatus according to claim 4, further comprising a light reflecting portion that reflects light on an outer surface of the top plate.   The substrate processing apparatus according to claim 4, further comprising a light diffusing unit that scatters and diffuses light on an outer surface of the bottom plate. The discharge cell is
A first gas introduction part for introducing a gas for plasma generation into a plasma generation space for generating plasma;
A first exhaust unit for exhausting the plasma generation space;
The substrate processing apparatus of any one of Claim 1 to 8 provided with these.   The substrate processing apparatus according to claim 9, further comprising a second gas introduction unit that introduces a processing gas for processing the substrate below the light irradiation unit.   The substrate processing apparatus according to claim 1, wherein the plasma light generated in the discharge cell is vacuum ultraviolet light.   The substrate processing method of processing a board | substrate with the substrate processing apparatus of any one of Claim 1 to 11.

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