JP2015138885A - substrate processing apparatus, shower plate and substrate processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the throughput of substrate processing and reduce the cost with keeping uniformity of the substrate processing by efficiently diffusing processing gas to be supplied to a substrate.SOLUTION: A COR processing apparatus 5 for processing a wafer W has a processing container 40 for air-tightly accommodating the wafer W, a mount table 41 on which the wafer W is mounted in the processing container 40, a shower plate 52 which is disposed to confront the wafer W mounted on the mount table 41 and has plural supply nozzles 90 formed therein, and processing gas supply sources 71, 74 for supplying processing gas through the shower plate 52 into the processing container 40. The supply nozzle 90 has a gas inlet hole which is formed to a predetermined position in the thickness direction of the shower plate 52 from the upper end face of the shower plate 52 to the lower end face thereof, and plural gas outlet holes which intercommunicate with the gas inlet hole in an oblique direction and extend to the lower end face of the shower plate 52.

Description

  The present invention relates to a substrate processing apparatus that performs chemical oxide removal processing using a predetermined processing gas, a shower plate used in the processing apparatus, and a substrate processing method using the substrate processing apparatus.

In recent years, with the miniaturization of semiconductor devices, instead of conventional etching techniques such as dry etching and wet etching, chemical oxide removal processing (Chemical
A technique called “Oxide Removal (COR)” that enables finer etching is drawing attention.

COR is a semiconductor wafer as a vacuum example workpiece (hereinafter, "wafer" hereinafter) with respect to the silicon oxide film on the surface (Si0 ₂ film), hydrogen fluoride as a process gas (HF) gas and ammonia (NH3) This is a process for supplying gases and reacting these gases with a silicon oxide film to generate products (for example, Patent Document 1).

  The product generated on the wafer surface by the COR is sublimated by performing a heat treatment in the next step, whereby the silicon oxide film is removed from the wafer surface.

JP 2007-214513 A

  In the COR processing as described above, a wafer is placed in a processing container held in a vacuum, and a processing gas is supplied from above the wafer. At this time, in order to uniformly process the wafer surface, the processing gas is supplied into the processing container through a shower plate provided above the wafer and having a plurality of openings penetrating in the thickness direction. There is. In this case, the shower plate and the wafer are separated from each other by a predetermined distance so that the distribution of the processing gas supplied to the wafer surface is uniform within the wafer surface. In particular, since the processing gas is released linearly downward from the opening of the shower plate, if the distance between the shower plate and the wafer is short, the processing gas reaches the wafer before it diffuses sufficiently, and as a result There arises a problem that etching occurs in a distribution in which openings are transferred onto the wafer.

  Further, in the COR processing, there is a demand for improvement in throughput and reduction in the amount of processing gas used. In such a case, by reducing the volume of the processing container, it is possible to improve the throughput by reducing the amount of processing gas used and shortening the evacuation time. However, in order to maintain the uniformity of wafer processing, it is necessary to provide a predetermined interval between the wafer and the shower plate as described above. For this reason, it has been difficult to satisfy both of the requirements such as improvement of throughput and the amount of processing gas used and the requirement of uniformity of wafer processing.

  The present invention has been made in view of the above points, and by efficiently diffusing a processing gas supplied to the substrate, the substrate processing uniformity is maintained and the substrate processing throughput is improved and the cost is reduced. It aims to plan.

  In order to achieve the above object, the present invention provides a substrate processing apparatus for processing a substrate, wherein the processing container for accommodating the substrate in an airtight manner, a mounting table for mounting the substrate in the processing container, and the above-described mounting table A shower plate disposed opposite to the substrate placed on the substrate and formed with a plurality of supply nozzles; and a processing gas supply source for supplying a processing gas into the processing container via the shower plate. The supply nozzle communicates in an oblique direction with respect to the gas inlet hole and a gas inlet hole formed to a predetermined position in the thickness direction of the shower plate from the upper end surface to the lower end surface of the shower plate. And a plurality of gas outlet holes extending to the lower end surface of the shower plate.

  The inventor has intensively studied a method for efficiently diffusing a processing gas supplied from, for example, a shower plate. As a result, instead of penetrating the opening formed in the shower plate in the thickness direction of the shower plate, the shower plate is formed up to a predetermined position in the thickness direction and then branched into a plurality of openings extending obliquely downward. It has been found that the processing gas can be efficiently diffused by suppressing the processing gas from being released linearly downward from the plate. The present invention is based on this finding, and according to the present invention, the shower plate communicates in an oblique direction with respect to the gas inlet hole in which the shower plate is formed up to a predetermined position in the thickness direction of the shower plate. And a plurality of gas outlet holes extending to the lower end surface of the shower plate. Therefore, it is possible to suppress the processing gas from being discharged linearly downward from the shower plate and efficiently diffuse the processing gas. As a result, the uniformity of wafer processing can be maintained even if the distance between the shower plate and the substrate is shorter than in the prior art. Therefore, it is possible to reduce the volume of the processing container by reducing the height of the processing container, reduce the cost by reducing the amount of processing gas used, and improve the throughput by shortening the evacuation time.

  The plurality of gas outlet holes may be arranged radially at equal intervals from the gas inlet hole in plan view.

  The lower end surface of the shower plate is provided with a plurality of recessed portions that are recessed toward the upper end surface side of the shower plate, and the end portion on the mounting table side of the gas outlet hole communicates with the recessed portion. Also good.

  The processing gas supply source includes a first gas supply unit that supplies a first processing gas and a second gas supply unit that supplies a second processing gas, and a gas inlet hole of the shower plate includes: You may have the 1st inlet hole connected to the said 1st gas supply part, and the 2nd inlet hole connected to the said 2nd gas supply part.

  Another aspect of the present invention is a shower plate that supplies a processing gas into a processing container of a substrate processing apparatus in which substrate processing is performed, and is formed on a disk-shaped main body having a predetermined thickness and the main body. A plurality of supply nozzles, wherein the supply nozzles are formed from the upper end surface of the main body portion toward the lower end surface to a predetermined position in the thickness direction of the main body portion, and the gas And a plurality of gas outlet holes extending in an oblique direction with respect to the inlet hole and extending to a lower end surface of the main body.

  The plurality of gas outlet holes may be arranged radially at equal intervals from the gas inlet hole in plan view.

  The lower end surface of the main body portion is provided with a plurality of hollow portions that are recessed toward the upper end surface side of the main body portion, and the end portion on the mounting table side of the gas outlet hole communicates with the hollow portion. Also good.

  According to another aspect of the present invention, there is provided a substrate processing method using the substrate processing apparatus, wherein a processing gas is supplied from the processing gas supply source to a gas inlet hole of the shower plate, and the gas inlet hole is supplied with the processing gas. A processing gas is supplied to the substrate in the processing container through the gas outlet hole that communicates.

  According to the present invention, by efficiently diffusing the processing gas supplied to the substrate, it is possible to improve the throughput of the substrate processing and reduce the cost while maintaining the uniformity of the substrate processing.

It is a top view which shows the outline of a structure of the substrate processing system provided with the COR processing apparatus which concerns on this Embodiment. It is a longitudinal cross-sectional view which shows the outline of a structure of the heat processing apparatus. It is a longitudinal cross-sectional view which shows the outline of a structure of a COR processing apparatus. It is a longitudinal cross-sectional view which shows the outline of a structure of a supply nozzle. It is a perspective view which shows the outline of a structure of a supply nozzle. It is a bottom view of a shower plate. It is a bottom view of the shower plate concerning other embodiments. It is an enlarged bottom view of the shower plate concerning other embodiments. It is sectional drawing which shows the outline of a structure of the gas outlet hole concerning other embodiment. It is sectional drawing which shows the outline of a structure of the gas outlet hole concerning other embodiment. It is a longitudinal cross-sectional view which shows the outline of a structure of the conventional supply nozzle. It is explanatory drawing showing the result of the comparative test at the time of changing the depth and diameter of a gas inlet hole. It is explanatory drawing which shows the outline of the connection state of a gas outlet hole and a hollow part. It is explanatory drawing showing the result of the comparative test at the time of changing the connection position of the diameter of a hollow part, and a hollow part and a gas outlet hole. It is explanatory drawing showing the result of the comparative test at the time of changing the connection angle of a gas inlet hole and a gas outlet hole. It is explanatory drawing which shows the simulation result of the flow of the gas discharge | released from the supply nozzle concerning this Embodiment. It is explanatory drawing which shows the simulation result of the flow of the gas discharge | released from the conventional supply nozzle.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol. FIG. 1 is a longitudinal sectional view schematically showing a substrate processing system 1 including a COR processing apparatus as a substrate processing apparatus according to the present embodiment.

  The substrate processing system 1 includes a loading / unloading unit 2 for loading / unloading a wafer W, two load lock chambers 3 provided adjacent to the loading / unloading unit 2, and the opposite side of the loading / unloading unit 2 in each load lock chamber 3. And a COR processing apparatus 5 provided adjacent to the opposite side of each load lock chamber 3 in the heat treatment apparatus 4.

  The carry-in / out unit 2 includes a transfer chamber 10, a wafer transfer mechanism 11 having a plurality of transfer arms, and a mounting table 12 on which a cassette C containing a plurality of wafers W is mounted. Further, the transfer chamber 10 is provided with an alignment device 13 adjacent to the wafer for alignment. The wafer transfer mechanism 11 is disposed inside the transfer chamber 10. The transfer arm of the wafer transfer mechanism 11 is movable in the horizontal direction, the θ direction, and the vertical direction, for example, and can transfer the wafer W between the cassette C, the load lock chamber 3 and the alignment device 13.

  A gate valve 14 is provided between each load lock chamber 3 and the transfer chamber 10 so that the inside of the load lock chamber 3 can be depressurized to a predetermined pressure by an exhaust mechanism (not shown). A wafer transfer mechanism 15 is provided inside each load lock chamber 3. The wafer transfer mechanism 15 includes a transfer arm that can move horizontally in the direction of the COR processing apparatus 5, and the wafer W is transferred between the load lock chamber 3, the heat treatment apparatus 4, and the COR processing apparatus 5 by the transfer arm. Can be transported.

  For example, as shown in FIG. 2, the heat treatment apparatus 4 includes an airtight processing container 20 and a mounting table 21 on which a wafer W is mounted in the processing container 20. For example, a resistance heating type heater 22 is built in the mounting table 21. The heater 22 can heat the wafer W on the mounting table 21 by being fed from a power source (not shown). In the mounting table 21, a process called PHT (Post Heat Treatment) is performed in which the wafer W subjected to the COR process by the COR processing apparatus 5 is heated to vaporize a reaction product generated by the COR process.

  On the side of the load lock chamber 3 of the processing container 20, a loading / unloading port 20a for loading / unloading the wafer W to / from the load locking chamber 3 and a gate valve 23 for opening / closing the loading / unloading port 20a are provided. Further, a loading / unloading port 20b for loading / unloading the wafer W to / from the processing apparatus 5 and a gate valve 24 for opening / closing the loading / unloading port 20b are also provided on the COR processing apparatus 5 side of the processing container 20. .

  A gas supply mechanism 25 that supplies an inert gas such as nitrogen into the processing container 20 is connected to the processing container 20 via a gas supply pipe 26. The gas supply pipe 26 is provided with a flow rate adjusting mechanism 27 that adjusts the supply amount of nitrogen gas. Further, an exhaust mechanism 30 that exhausts the inside of the processing container 20 is connected to the bottom surface of the processing container 20 via an exhaust pipe 31. The exhaust pipe 31 is provided with an adjustment valve 32 that adjusts the exhaust amount by the exhaust mechanism 30.

  For example, as shown in FIG. 3, the COR processing apparatus 5 includes an airtight processing container 40 and a mounting table 41 on which the wafer W is mounted in the processing container 20. The processing container 40 has a container part 42 formed in a substantially cylindrical shape with a bottom that opens upward, and a lid part 43 that hermetically closes the upper surface of the container part 42. A loading / unloading port 42 a for loading / unloading the wafer W to / from the heat treatment apparatus 4 is provided on the side surface of the container unit 42. The loading / unloading port 42a is opened and closed by the gate valve 24 described above.

  A shower head 50 is provided on the lower surface of the lid 43 of the processing container 20 so as to face the mounting table 41. The shower head 50 includes, for example, a substantially cylindrical support member 51 having an open bottom surface, a shower plate 52 provided on the inner surface of the support member 51 at a predetermined distance from the ceiling portion of the support member 51, and a shower. A plate 53 provided parallel to the shower plate 52 is provided between the plate 52 and the support member 51. A first space 54 is formed between the ceiling portion of the support member 51 and the plate 53, and a second space 55 is formed between the plate 53 and the shower plate 52.

  The shower plate 52 has a main body 52 a and a plurality of supply nozzles 90 for supplying a processing gas to the wafer W on the mounting table 41. In the plate 53, a plurality of gas flow paths 60 penetrating the plate 53 in the thickness direction are formed. The number of the gas flow paths 60 is approximately half that of the supply nozzles 90. The gas flow paths 60 extend to the upper end surface of the shower plate 52 below the plate 53, and the upper end portions of the supply nozzles 90. It is connected to the. Therefore, the interior of the gas passage 60 and the supply nozzle 90 connected to the gas passage 60 is isolated from the second space 55. The main body 52a and the plate 53 of the shower plate 52 are made of a metal such as aluminum, for example. In the present embodiment, the distance between the surface of the wafer W on the mounting table 41 and the lower end surface of the shower plate 52 is set to be approximately 50 mm. The shower plate 52 has a thickness of about 15 mm.

  A first gas supply source 71 is connected to the first space 54 via a first gas supply pipe 70. The first gas supply source 71 is configured to be able to supply a mixed gas of hydrogen fluoride (HF) gas, which is a reaction gas, and argon (Ar) gas, which is a dilution gas, as a first processing gas. The first gas supply pipe 70 is provided with a flow rate adjusting mechanism 72 that adjusts the supply amount of the first processing gas. The first processing gas supplied from the first gas supply source 71 is supplied into the processing container 40 through the first space 54, the gas flow path 60 of the plate 53, and the supply nozzle 90 of the shower plate 52. .

A second gas supply source 74 is connected to the second space 55 via a second gas supply pipe 73. The second gas supply source 74 is configured to be able to supply a mixed gas of ammonia (NH ₃ ) gas that is a reaction gas and nitrogen (N ₂ ) gas that is a dilution gas as a second processing gas. The second gas supply pipe 73 is provided with a flow rate adjusting mechanism 75 that adjusts the supply amount of the second processing gas. Note that the dilution gas is not limited to the present embodiment, and for example, only argon gas, only nitrogen gas, or other inert gas may be used. The second processing gas supplied from the second gas supply source 74 is supplied into the processing container 40 through the second space 55 and the supply nozzle 90 of the shower plate 52. Therefore, the first processing gas and the second processing gas are mixed for the first time at a position below the shower plate 52 in the processing container 40.

  The mounting table 41 has a substantially cylindrical shape and is supported on the bottom surface of the container part 42. The mounting table 41 includes a temperature adjustment mechanism 41 a that adjusts the temperature of the mounting table 41. The temperature adjustment mechanism 41 a adjusts the temperature of the mounting table 41 by circulating a coolant such as water, and controls the temperature of the wafer W on the mounting table 41.

  An exhaust mechanism 80 for exhausting the inside of the processing container 40 is connected via an exhaust pipe 81 on the bottom surface of the container portion 42 of the processing container 40 and outside the mounting table 41. The exhaust pipe 81 is provided with an adjustment valve 82 that adjusts the amount of exhaust by the exhaust mechanism 80. Further, pressure measuring mechanisms 83 a and 83 b for measuring the pressure in the processing container 40 are provided on the side wall of the container portion 42. The pressure measuring mechanism 83a is used for high pressure, and the pressure measuring mechanism 83b is used for low pressure. As the pressure measuring mechanisms 83a and 83b, for example, a capacitance manometer is used.

  Next, the configuration of the shower plate 52 will be described in detail. The supply nozzle 90 formed in the main body 52a of the shower plate 52 is provided at a position different from the supply nozzle 90a and the gas flow path 60 provided at a position corresponding to the gas flow path 60 of the plate 53 as described above. And a supply nozzle 90b. The supply nozzle 90a and the supply nozzle 90b are alternately arranged concentrically, for example.

  For example, as shown in FIG. 4, the supply nozzle 90 includes a gas inlet hole 91 formed at a predetermined depth in the thickness direction of the main body 52 a from the upper end to the lower end of the main body 52 a of the shower plate 52. The gas outlet hole 92 communicates in an oblique direction with a predetermined angle θ with respect to the vicinity of the lower end of the gas inlet hole 91 and extends to the lower end surface of the shower plate 52. The diameter of the gas outlet hole 92 is smaller than the diameter of the gas inlet hole 91, and the processing gas discharged from the shower plate 52 into the processing container 40 does not flow backward toward the first space 54 and the second space 55. It is set to such a value. In the present embodiment, the diameter of the gas inlet hole 91 is set to 3 mm, for example, and the diameter of the gas outlet hole 92 is set to 0.5 mm, for example. In FIG. 4, the gas inlet hole of the supply nozzle 90 a connected to the gas channel 60 is a first inlet hole 91 a, and the gas that is not connected to the gas channel 60, that is, communicates with the second space 55. Although the inlet hole is described as the second inlet hole 91b, the first inlet hole 91a and the second inlet hole 91b have the same configuration. The configuration of the supply nozzle 90a and the supply nozzle 90b is also the same.

  For example, as shown in FIG. 5, four gas outlet holes 92 are provided from the vicinity of the lower end of the gas inlet hole 91 radially at an equal interval of 90 degrees with the gas inlet hole 91 as the center. Therefore, when the shower plate 52 is viewed from below, a set of four gas outlet holes 92 are arranged on the entire surface of the shower plate 52 at equal intervals, as shown in FIG. In FIG. 6, in order to distinguish the gas outlet hole 92 of the supply nozzle 90a from the gas outlet hole 92 of the supply nozzle 90b, the gas outlet hole 92 of the supply nozzle 90a is indicated by a solid circle and the gas outlet hole of the supply nozzle 90b. 92 are drawn surrounded by broken-line circles. By providing the supply nozzle 90 having such a configuration in the shower plate 52, the processing gas discharged from the supply nozzle 90 is efficiently diffused, and the processing gas is discharged linearly downward from the shower plate 52. Is suppressed. The inventor formed the gas outlet hole 92 in an oblique direction with respect to the vicinity of the lower end of the gas inlet hole 91 using the conventional supply nozzle and the supply nozzle according to the present embodiment. It is based on the result of the comparative test. The result of the comparative test will be described later.

  Moreover, the end part by the side of the mounting base 41 of each gas outlet hole 92 is connected to the hollow part 93 formed in the lower end surface of the shower plate 52, for example. The recess 93 is recessed in a substantially conical shape, for example, toward the upper end surface of the shower plate 52. Therefore, the end of the gas outlet hole 92 on the mounting table 41 side has a shape that is larger than the end of the gas outlet hole 92 on the gas inlet hole 91 side. By providing the depression 93, the processing gas released from the gas outlet hole 92 forms a turbulent flow in the depression 93, for example. Therefore, the processing gas is further diffused in the depression 93, and the processing gas can be diffused more efficiently in the processing container.

  The substrate processing system 1 is provided with a control device 100 as shown in FIG. The control device 100 is, for example, a computer and has a program storage unit (not shown). The program storage unit stores a program for controlling the processing of the wafer W in the substrate processing system 1. The program is recorded on a computer-readable storage medium such as a computer-readable hard disk (HD), flexible disk (FD), compact disk (CD), magnetic optical desk (MO), or memory card. Or installed in the control device 100 from the storage medium.

  The substrate processing system 1 according to the present embodiment is configured as described above. Next, processing performed using the substrate processing system 1 will be described.

  First, a cassette C containing a plurality of wafers W having a silicon oxide film on the surface is placed at a predetermined position on the mounting table 12 of the carry-in / out unit 2. Thereafter, with the gate valve 14 opened, the wafer W is transferred from the cassette C to the wafer transfer mechanism 15 in the load lock chamber 3 by the wafer transfer mechanism 11.

  Next, after closing the gate valve 14 and exhausting the inside of the load lock chamber 3 to reach a predetermined pressure, the gate valve 23 and the gate valve 24 are opened, and the wafer transfer mechanism 15 is used to place the mounting table 41 on the COR processing apparatus 5. A wafer W is placed. Next, after the wafer transfer mechanism 15 has exited to the load lock chamber 3, the gate valve 24 is closed to seal the inside of the processing container 40.

  Thereafter, the processing container 40 is evacuated to a predetermined pressure, and the temperature adjustment mechanism 41a adjusts the wafer W for the mounting table 41 to a predetermined temperature, for example, 20 ° C. to 40 ° C. in the present embodiment. Next, the first processing gas and the second processing gas are supplied into the processing container 40 from the first gas supply source 71 and the second gas supply source 74, respectively. At this time, the first processing gas and the second processing gas are supplied into the processing container 40 from the gas outlet holes 92 of the supply nozzle 90a and the supply nozzle 90b without being mixed in the shower head 50, and are subjected to COR processing. Is done. In the COR process, the silicon oxide film on the surface of the wafer W chemically reacts with hydrogen fluoride gas and ammonia gas, and as a reaction product, ammonium fluorosilicate (AFS) or water is generated and held on the surface of the wafer W. It becomes a state. At this time, the processing gas supplied from the supply nozzle 90 is efficiently diffused in the processing container 40 and is uniformly discharged to the entire surface of the wafer W, so that a uniform COR processing is performed in the wafer W surface.

  When the COR processing is performed, the gate valves 23 and 24 are opened, and the wafer W on the mounting table 41 is transferred onto the mounting table 21 of the heat treatment apparatus 4 by the wafer transfer mechanism 15. Next, after the wafer transfer mechanism 15 is retracted to the load lock chamber 3, the gate valves 23 and 24 are closed, and nitrogen gas is introduced into the processing container 20. At the same time, the wafer W on the mounting table 21 is heated by the heater 22, and the reaction product generated by the COR process is vaporized and removed.

  Thereafter, the gate valves 14 and 23 are sequentially opened, and the wafer W on the mounting table 21 is transferred to the wafer transfer mechanism 11 by the wafer transfer mechanism 15. Next, the wafer W is accommodated in a predetermined cassette C, and a series of wafer processing ends.

  According to the above embodiment, the supply nozzle 90 formed in the shower plate 52 is formed with respect to the gas inlet hole 91 formed up to a predetermined position in the thickness direction of the shower plate 52 and the gas inlet hole 91. And a plurality of gas outlet holes 92 extending in an oblique direction and extending to the lower end surface of the shower plate 52. Therefore, it is possible to suppress the processing gas from being discharged linearly downward from the shower plate 52 and efficiently diffuse the processing gas. As a result, even if the distance between the shower plate and the substrate is made shorter than before, the processing gas can be supplied uniformly within the wafer surface and the uniformity of the wafer processing can be maintained. Therefore, it is possible to reduce the volume of the processing container 40 by reducing the height of the processing container 40, reduce costs by reducing the amount of processing gas used, and improve throughput by shortening the evacuation time.

  Further, since the depression 93 is provided in the lower end surface of the shower plate 52 and the gas outlet hole 92 is communicated with the depression 93, the processing gas released from the gas outlet hole 92 is further diffused in the depression 93. . Therefore, the processing gas can be diffused more efficiently, and the uniformity of wafer processing can be further improved.

  In the above embodiment, the gas outlet holes 92 are provided radially at a pitch of 90 degrees with respect to the gas inlet holes 91, but the arrangement of the gas outlet holes 92 is not limited to the contents of the present embodiment. For example, three gas outlet holes 92 may be provided radially with a pitch of 120 degrees around the gas inlet holes 91, or five gas outlet holes 92 may be provided with a pitch of 72 degrees. Furthermore, the gas outlet holes 92 are not necessarily provided at regular intervals if the processing gas can be efficiently diffused into the processing container 40.

  Further, the gas outlet hole 92 is not necessarily connected near the lower end of the gas inlet hole 91, and may be connected near the middle part of the gas inlet hole 91. However, if the connection height of the gas outlet hole 92 with respect to the gas inlet hole 91 is changed in the supply nozzle 90, the gas outlet hole 92 provided on the upper side of the gas inlet hole 91 is less likely to flow the processing gas. The arrangement of the holes 92 in the height direction is preferably unified within the supply nozzle 90. In addition, the angle θ at which the gas outlet hole 92 communicates with the gas inlet hole 91 may be different for each gas outlet hole 92. However, if the angle θ is too small, the processing gas is not diffused by the shower plate 52 and is vertically downward. Since the processing gas is released linearly at a close angle, the angle θ is preferably 30 degrees or more.

  In the above embodiment, the supply nozzle 90a and the supply nozzle 90b are arranged at equal intervals. However, as shown in FIG. 7, the supply nozzle 90a and the supply nozzle 90b may be alternately arranged concentrically. The arrangement may be arbitrarily set as long as the first processing gas and the second processing gas are appropriately mixed in the processing container 40. In FIG. 6, the gas outlet holes 92 of the supply nozzles 90a and 90b are provided at the same angle. However, for example, as shown in FIG. 8, the angle of the gas outlet hole 92 is changed between the supply nozzle 90a and the supply nozzle 90b. Alternatively, the angle of the gas outlet hole 92 may be changed for each supply nozzle 90.

  Moreover, in the above embodiment, although the hollow part 93 was provided in the front-end | tip at the side of the mounting base 41 of the gas outlet hole 92, this hollow part 93 does not necessarily need to be provided. However, based on a comparative test described later, it is preferable to provide the depression 93 from the viewpoint of efficiently diffusing the processing gas. According to the present inventor, if the turbulent flow of the processing gas can be formed in the depression 93, the depression 93 does not necessarily have a conical shape, for example, a pyramid shape, a cylindrical shape, or a rectangular shape. Also good. Moreover, as the hollow part 93, for example, as shown in FIG. 9, the shape of the diameter of the gas outlet hole 92 may be gradually widened. As shown in FIG. A recess 93 having a cylindrical protrusion 93a may be formed, and the gas outlet hole 92 may be connected to the protrusion 93a.

  In the above embodiment, the shower head 50 is configured by the shower plate 52 and the plate 53 and configured to supply the first processing gas and the second processing gas. However, the supply according to the present embodiment is provided. Naturally, the nozzle 90 can also be applied to the shower head 50 and the shower plate 52 that supply only one kind of gas.

  Next, the result of a comparison test between the supply nozzle according to the present embodiment, 90 and a conventional supply nozzle will be described. FIG. 11 shows a cross-sectional view of a conventional supply nozzle 200 used in this comparative test. The conventional supply nozzle 200 is the same as the supply nozzle 90 according to the present embodiment except that one gas outlet hole 201 is provided at the lower end of the gas inlet hole 91 with an angle θ of 0 (zero). It is.

  In the comparative test, a test gas was discharged from the supply nozzle 90 and the supply nozzle 200, respectively, and the pressure of the gas released at a predetermined distance away from the supply nozzles 90 and 200 vertically was measured. As Comparative Examples 1 and 2, the pressure at positions 50 mm and 100 mm away from the supply nozzle 200 was measured, and as the example, the pressure at a position 50 mm away from the supply nozzle 90 was measured within a circle having a diameter of 100 mm. At this time, in the supply nozzle 90, the diameter of the gas inlet hole 91, the depth of the gas inlet hole 91 from the upper end surface of the shower plate 52, the presence / absence of the recessed portion 93 at the tip of the gas outlet hole 92, and the gas to the recessed portion 93 The test was performed by changing the connection position of the outlet hole 92, the diameter of the substantially conical recess 93, and the angle θ at which the gas outlet hole 92 communicates with the gas inlet hole 91. The pressure in the processing container 40 was about 80 Pa (0.6 Torr), the temperature in the processing container 40 was 60 ° C., and nitrogen gas was supplied as a test gas at a flow rate of 440 sccm.

  In FIG. 12, the measurement result about the pressure of the gas at the time of changing the length of the gas inlet hole 91 and the diameter of the gas inlet hole 91 is shown. In the comparative example shown in FIG. 12, the diameter of the gas inlet hole 91 is 3 mm, and the depth of the gas inlet hole 91 is constant at 9.5 mm. In the embodiment, the diameter of the gas inlet hole 91 is in the range of 2 mm to 5 mm. The depth of the gas inlet hole 91 is changed between 5 mm and 10 mm. In the measurement of FIG. 12, a recess 93 is provided at the tip of the gas outlet hole 92, the diameter of the substantially conical recess 93 is 3 mm, and the connection position of the gas outlet hole 92 to the recess 93 is shown in FIG. The position of the circled number “2” shown, the angle θ at which the gas outlet hole 92 communicates with the gas inlet hole 91 is fixed at 45 degrees. Moreover, the pressure shown in FIG. 12 is a difference value (ΔP) between the maximum value and the minimum value of the pressure measured within the above-described circle having a diameter of 100 mm. Therefore, it can be evaluated that the smaller the value, the more uniformly the gas is supplied in the plane.

  As shown in FIG. 12, in Examples 1 to 4 where the diameter of the gas inlet hole 91 is 2 mm, 3 mm, 4 mm, and 5 mm, the pressure is measured 50 mm below the conventional supply nozzle 200 in all cases. The pressure difference ΔP is smaller than that of the comparative example 1. Therefore, like the supply nozzle 90, the plurality of gas outlet holes 92 communicate with the gas inlet hole 91 at a predetermined angle θ, thereby measuring the wafer W measured at the same distance from the supply nozzle. It can be confirmed that the pressure difference ΔP of the processing gas within the surface can be reduced as compared with the case where the supply nozzle 200 is used, in other words, the processing gas can be supplied more uniformly into the wafer W surface. In particular, when the diameter of the gas inlet hole 91 is 3 mm and the depth is 10 mm (Example 2), the pressure difference ΔP at a position 100 mm away from the conventional supply nozzle 200 is smaller. Therefore, by using the shower plate 52 having the supply nozzle 90 of the second embodiment, the distance between the wafer W and the shower plate 52 is halved compared to the case of using the shower plate having the conventional supply nozzle 200. it can. As a result, it is possible to reduce the volume of the processing container 40 by reducing the height of the processing container 40, thereby reducing the cost and improving the throughput of the wafer processing.

  Next, FIG. 14 shows the measurement result of the gas pressure difference ΔP when the diameter D of the depression 93 shown in FIG. 13 and the connection position of the gas outlet hole 92 to the depression 93 are changed. In Comparative Examples 1 and 2 shown in FIG. 14, the recess 93 has a conical shape with a diameter of 3 mm, and the gas outlet hole 92 is connected to the upper end of the recess 93. In Examples 1 to 3, the diameter of the hollow portion 93 is changed at 1 mm intervals in the range of 2 mm to 4 mm, and the connection position of the gas outlet hole 92 to the hollow portion 93 is set near the upper end portion of the hollow portion 93 (FIG. 13). The position of the circled number “1” shown in FIG. 13), the vicinity of the middle part (the position of the rounded number “2” shown in FIG. 13), and the vicinity of the lower end (the position of the number “3” shown in FIG. 13) ing. In the fourth embodiment, the gas outlet hole 92 is directly communicated with the lower end surface of the shower plate 52 without providing the recess 93. In the measurement of FIG. 14, the diameter of the gas inlet hole 91 is 3 mm, the depth of the gas inlet hole 91 is 9 mm, and the angle θ at which the gas outlet hole 92 communicates with the gas inlet hole 91 is fixed at 45 degrees. .

  As shown in FIG. 14, the first to third embodiments in which the depression 93 is provided have a smaller pressure difference Δ than the fourth embodiment in which the depression 93 is not provided in any case. From this, it can be confirmed that the processing gas is efficiently diffused by connecting the gas outlet hole 92 to the recess 93, and the uniformity of the processing gas in the wafer W plane can be improved. Moreover, also in Example 4 which does not provide the hollow part 93, pressure difference (DELTA) P is smaller than the comparative example 1 which measured the pressure 50 mm below the conventional supply nozzle 200. FIG. From this, it can be confirmed that the processing gas can be diffused more efficiently than the conventional supply nozzle 90 by using the supply nozzle 90 even when the depression 93 is not provided. In addition, from the results of Example 3, the pressure difference ΔP decreases as the connection position of the gas outlet hole 92 to the recess 93 becomes lower than the recess 93. From this, it can be confirmed that the gas outlet hole 92 is preferably provided in the vicinity of the lower end portion of the recessed portion 93.

  Next, FIG. 15 shows the measurement result of the gas pressure difference ΔP when the angle θ at which the gas outlet hole 92 communicates with the gas inlet hole 91 is changed. Example 1 is a measurement result when the angle θ is 45 degrees, and Example 2 is a measurement result when the angle θ is 60 degrees. In the measurement of FIG. 15, a recess 93 is provided at the tip of the gas outlet hole 92, the diameter of the substantially conical recess 93 is 3 mm, and the connection position of the gas outlet hole 92 to the recess 93 is shown in FIG. The position of the circled number “2” shown, the diameter of the gas inlet hole 91 is 3 mm, and the depth of the gas inlet hole 91 is 9 mm.

  From the results shown in FIG. 15, it can be confirmed that the pressure difference ΔP is smaller in the second embodiment in which the angle θ is larger than in the first embodiment. Further, in both Examples 1 and 2, the pressure difference ΔP is smaller than Comparative Example 1 in which the pressure was measured 50 mm below the conventional supply nozzle 200, so the angle θ is in the range of 90 degrees to 120 degrees. It can be inferred that it can be set arbitrarily.

  As another comparative test, a simulation was performed on the gas flow when a predetermined gas was released from the supply nozzle 90 according to the present embodiment and the conventional supply nozzle 200. The results are shown in FIGS. FIG. 16 is a diagram schematically showing a gas flow when a predetermined gas is released from the supply nozzle 90 according to the present embodiment. From FIG. 16, the gas diffuses immediately below the supply nozzle 90. It can be confirmed that the flow is almost parallel.

  FIG. 17 is a diagram schematically showing a gas flow when a predetermined gas is discharged from the conventional supply nozzle 200, and the gas discharged from the conventional supply nozzle 200 has a directivity that linearly spreads radially. It can be confirmed that it has. Therefore, it is confirmed from this result that the supply nozzle 200 needs to have a larger distance between the supply nozzle 200 and the wafer W than the supply nozzle 90 in order to reduce the pressure difference ΔP in the wafer surface. it can.

  The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention pertains can make various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention. In the above-described embodiment, the case where the COR processing is performed on the wafer has been described as an example. However, the present invention can be applied to other wafer processing using a processing gas, for example, plasma processing.

DESCRIPTION OF SYMBOLS 1 Substrate processing system 2 Loading / unloading part 3 Load lock chamber 4 Heat processing apparatus 5 COR processing apparatus 10 Transfer chamber 11 Wafer transfer mechanism 12 Mounting table 13 Alignment apparatus 14 Gate valve 20 Processing container 21 Mounting table 30 Exhaust mechanism 40 Processing container 41 Mounting table 50 Shower head 51 Support member 51
52 Shower Plate 53 Plate 71 First Gas Supply Source 74 Second Gas Supply Source 80 Exhaust Mechanism 90 Supply Nozzle 91 Gas Inlet Hole 92 Gas Outlet Hole 93 Indentation Part 100 Controller W Wafer

Claims (8)

A substrate processing apparatus for processing a substrate,
A processing container for hermetically containing the substrate;
A mounting table for mounting a substrate in the processing container;
A shower plate disposed opposite to the substrate placed on the mounting table, wherein a plurality of supply nozzles are formed;
A processing gas supply source for supplying a processing gas into the processing container through the shower plate,
The supply nozzle communicates in an oblique direction with respect to the gas inlet hole, a gas inlet hole formed up to a predetermined position in the thickness direction of the shower plate from the upper end surface to the lower end surface of the shower plate, And a plurality of gas outlet holes extending to the lower end surface of the shower plate. 2. The substrate processing apparatus according to claim 1, wherein the plurality of gas outlet holes are arranged radially at equal intervals from the gas inlet hole in a plan view. The lower end surface of the shower plate is provided with a plurality of recessed portions that are recessed toward the upper end surface side of the shower plate,
The substrate processing apparatus according to claim 1, wherein an end of the gas outlet hole on the mounting table side communicates with the recess. The processing gas supply source includes a first gas supply unit that supplies a first processing gas and a second gas supply unit that supplies a second processing gas,
The gas inlet hole of the shower plate has a first inlet hole connected to the first gas supply part and a second inlet hole connected to the second gas supply part. The substrate processing apparatus as described in any one of Claims 1-3. A shower plate for supplying a processing gas into a processing container of a substrate processing apparatus in which substrate processing is performed,
A disc-shaped main body having a predetermined thickness;
A plurality of supply nozzles formed in the main body,
The supply nozzle communicates in an oblique direction with respect to the gas inlet hole, a gas inlet hole formed up to a predetermined position in the thickness direction of the main body part from the upper end surface to the lower end surface of the main body part, And a plurality of gas outlet holes extending to the lower end surface of the main body. 6. The shower plate according to claim 5, wherein the plurality of gas outlet holes are arranged radially at equal intervals from the gas inlet hole in a plan view. The lower end surface of the main body is provided with a plurality of recessed portions that are recessed toward the upper end surface of the main body,
The shower plate according to claim 5, wherein an end of the gas outlet hole on the mounting table side communicates with the recess. A substrate processing method using the substrate processing apparatus according to claim 1,
Supplying a processing gas from the processing gas supply source to the gas inlet hole of the shower plate;
A substrate processing method, comprising: supplying a processing gas to a substrate in the processing container through the gas outlet hole communicating with the gas inlet hole.

Images