JP2018056300A - Substrate processing apparatus and substrate processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To heat, in an easy method, and supply a processing gas to a wafer in supplying the processing gas to the wafer having been heated in a processing container.SOLUTION: When a wafer W having adsorbed a DCS gas is heated in a processing container and supplied with an Ogas, an Ogas supply nozzle 4 is formed of double pipes of an outer pipe 41 and an inner pipe 40. Further, a pipe wall part of a tip-side part of the inner pipe 40 is made of a porous material 40, and the Ogas is passed through a porous material 40 having been heated as the wafer W is heated to heat the Ogas. Further, the outer pipe 41 is provided surrounding the porous material 40a of the inner pipe 40, a buffer space is formed between the inner pipe 40 and outer pipe 41, and the Ogas discharged from the inner pipe 41 is raised in pressure in the buffer space to be discharged toward the wafer W from a discharge port 42. With this structure, the Ogas is increased in flow velocity to be discharged toward the wafer W.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a technique for performing processing by supplying a processing gas to a substrate heated in a processing container.

  As one method for forming a thin film such as a silicon oxide film on a semiconductor wafer (hereinafter referred to as “wafer”) as a substrate, a source gas and a reactive gas are sequentially supplied to the surface of the wafer. An ALD (Atomic Layer Deposition) method of laminating reaction products is known. As a film forming apparatus for performing a film forming process using this ALD method, for example, as described in Patent Document 1, a rotation table for arranging and revolving a plurality of wafers in a circumferential direction is provided in a processing container. Configuration.

  In such a film forming apparatus, a gas nozzle is provided so as to extend horizontally in the radial direction of the rotary table, and a large number of gas discharge holes are arranged on the lower side of the gas nozzle in an area corresponding to the passing area of the wafer. The rotating table is rotated while the wafer is heated by the heating unit provided below the rotating table, and gas is supplied downward from the source gas supply unit and the reaction gas supply unit that are spaced apart from each other in the circumferential direction of the rotating table. By discharging, each of the source gas and the reaction gas is supplied to the entire surface of the wafer.

As an example of a film forming process, a source gas such as DCS (dichlorosilane) and an oxidizing gas such as O ₃ (ozone) are alternately supplied to the wafer to form a SiO ₂ film (silicon oxide film). Is mentioned. However, the appropriate wafer temperature is different between DCS gas and O ₃ gas, and when the wafer heating temperature is set, for example, from the viewpoint of increasing the adsorption efficiency of DCS gas, the activation of O ₃ gas is lowered. End up. This results because some specifications required for the SiO ₂ film in some cases sufficient quality can not be secured, or to excite the O ₃ gas (plasma) for example to facilitate the activation of the O ₃ gas, O ₃ gas In some cases, the film was modified by plasma after the supply. On the other hand, if the heating temperature of the wafer is set from the viewpoint of increasing the activity of the O ₃ gas, the DCS gas may self-decompose in the gas nozzle and adhere to the gas nozzle, which may cause generation of particles.
If a gas having a low temperature is supplied when supplying a processing gas to the wafer, the temperature of the wafer may be lowered and the film quality may be deteriorated depending on the type of process. Therefore, a technique for heating and supplying the processing gas may be required.

JP 2010-239103 A

  The present invention has been made under such circumstances, and its purpose is to supply a processing gas to an appropriate temperature by heating the processing gas to an appropriate temperature when supplying the processing gas to the substrate heated in the processing container. It is to provide a technology that can do.

The substrate processing apparatus of the present invention is a substrate processing apparatus for performing processing by supplying a processing gas to a substrate heated in a processing container.
A placement section for placing the substrate in the processing container;
A heating unit for heating the substrate placed on the placement unit;
A gas supply unit provided in the processing container for discharging a processing gas sent from a processing gas supply source;
An exhaust part for exhausting the inside of the processing container,
The gas supply section includes a partition member that partitions a gas passage space, and a portion interposed between an atmosphere in which a substrate is placed and the passage space is made of a porous material,
The processing gas that has passed through the partition member is discharged to the outside of the partition member through the porous material.

The substrate processing method of the present invention is provided in a processing container, defines a passage space for a gas sent from a processing gas supply source, and a portion interposed between an atmosphere in which the substrate is placed and the passage space. Using a substrate processing apparatus that includes a gas supply unit including a partition member made of a porous material, supplies a processing gas to a substrate heated in a processing container, and performs processing.
Placing the substrate in a processing vessel;
Heating the substrate placed in the processing vessel;
Discharging the processing gas sent from the processing gas supply source toward the substrate;
Evacuating the inside of the processing vessel,
The step of heating the porous material by heating the substrate and discharging the processing gas toward the substrate includes the step of passing the processing gas that has passed through the partition member through the heated porous material. It is characterized by discharging outside.

  The present invention relates to a substrate processing apparatus for performing processing by supplying a processing gas discharged from a gas supply unit to a substrate heated in a processing container, wherein the processing gas supplied to the gas supply unit and a gas passage space It is configured to be discharged through a porous material provided between the substrate and the atmosphere in which the substrate is placed. Therefore, the time until the processing gas is supplied from the gas passage space to the atmosphere in which the substrate is placed becomes long, and the contact area between the porous material and the processing gas is widened, so that heat exchange is performed efficiently. Accordingly, the processing gas can be heated to an appropriate temperature and supplied to the substrate by the porous material heated by heating the substrate.

It is a longitudinal cross-sectional view of the film-forming apparatus which concerns on 1st Embodiment. It is a top view of the film-forming apparatus which concerns on 1st Embodiment. It is a cross-sectional perspective view of an O ₃ gas supply nozzle. O ₃ is a side sectional view of a gas supply nozzle. O ₃ is a cross-sectional view of a gas supply nozzle. O ₃ is an explanatory diagram showing the operation of the gas supply nozzles. O ₃ is an explanatory diagram showing the operation of the gas supply nozzles. It is a disassembled perspective view which shows the other example of a gas supply part. It is a block diagram which shows the other example of a gas supply part. It is explanatory drawing which shows the effect | action of the other example of a gas supply part. It is sectional drawing which shows the further another example of a gas supply part. It is a longitudinal cross-sectional view of the film-forming apparatus which concerns on 2nd Embodiment. It is a sectional side view of the oxidizing gas supply nozzle in the film-forming apparatus. It is a longitudinal cross-sectional view of the film-forming apparatus which concerns on 3rd Embodiment.

An embodiment in which the substrate processing apparatus of the present invention is applied to a film forming apparatus will be described. As shown in FIGS. 1 and 2, the film forming apparatus includes a processing container 1 that is a vacuum container having a substantially circular planar shape, and a rotation center provided in the processing container 1. And a turntable 2 made of, for example, quartz for revolving the wafer W. The processing container 1 includes a top plate portion 11 and a container main body 12, and the top plate portion 11 is configured to be detachable from the container main body 12. A nitrogen (N ₂ ) gas is supplied to the central portion on the upper surface side of the top plate portion 11 as a separation gas in order to suppress mixing of different processing gases in the central portion in the processing vessel 1. A separation gas supply pipe 51 is connected.

  The rotary table 2 is fixed to a substantially cylindrical core portion 21 at the center, and is connected to the lower surface of the core portion 21 and extends in the vertical direction around the vertical axis in this example from above. It is configured so that it can rotate clockwise as seen. In FIG. 1, reference numeral 23 denotes a drive unit that rotates the rotary shaft 22 around the vertical axis, and reference numeral 20 denotes a case body that houses the rotary shaft 22 and the drive unit 23. A purge gas supply pipe 72 for supplying nitrogen gas as a purge gas to the lower region of the turntable 2 is connected to the case body 20.

  A circular recess 24 for mounting a wafer W having a diameter of, for example, 300 mm is formed on the surface portion of the turntable 2. As shown in FIG. It is provided in a plurality of places, for example, five places along the direction (circumferential direction). The recess 24 has a diameter dimension and a depth dimension so that when the wafer W is stored in the recess 24, the surface of the wafer W and the surface of the turntable 2 are aligned.

  As shown in FIG. 1, in the space between the rotary table 2 and the bottom surface of the processing container 1, a heating unit 7 that is a heating unit is provided over the entire circumference. In FIG. 1, 71 is a cover member provided on the side of the heating unit 7, and 70 is a quartz covering member that covers the upper side of the heating unit 7. The wafer W is heated to, for example, 400 ° C. by heat radiated from the heating unit 7 and radiant heat of the turntable 2 heated by the heating unit 7. Further, on the lower side of the heating unit 7, purge gas supply pipes 73 penetrating the bottom surface of the processing container 1 are provided at a plurality of locations in the circumferential direction.

  As shown in FIG. 2, a transfer port 15 for transferring the wafer W between an external transfer arm (not shown) and the rotary table 2 is formed on the side wall of the processing container 1. A gate valve (not shown) can be opened and closed in an airtight manner. The recess 24 of the turntable 2 is transferred to and from the transfer arm at a position facing the transfer port 15, and the recess 24 is provided below the turntable 2 at a portion corresponding to the transfer position. A lifting pin and a lifting mechanism (both not shown) for transferring the wafer W from the back surface are provided.

As shown in FIG. 2, the separation gas supply nozzle 34 and the silicon compound are placed in the clockwise direction as viewed from the transfer port 15 (in the rotational direction of the rotary table 2) at positions facing the passage areas of the recess 24 in the rotary table 2. A DCS gas supply nozzle 30 for supplying a gas containing, for example, DCS (dichlorosilane), a separation gas supply nozzle 37, and an O ₃ (ozone) gas supply nozzle 4 serving as a gas supply section are arranged in this order in the circumferential direction (rotation). The rotation direction of the table 2 is spaced from each other.

  The DCS gas supply nozzle 30 extends from the outer peripheral wall of the processing container 1 toward the center, and is provided so as to straddle the region through which the wafer W passes when the turntable 2 is rotated. The DCS gas supply nozzle 30 is configured in a cylindrical shape with a sealed tip, and a plurality of gas discharge holes are formed on the lower surface of the DCS gas supply nozzle 30 in a range across the region through which the wafer W passes as shown in FIG. 31 is provided.

  As shown in FIG. 2, the base end side of the DCS gas supply nozzle 30 is connected to a port 12 a formed in the container body 12. One end of a DCS gas supply pipe 32 is connected to the port 12 a from the outside of the container body 12, and a DCS gas supply source 33 is connected to the other end of the DCS gas supply pipe 32. The DCS gas supply pipe 32 is provided with a valve V32 and a flow rate adjusting unit M32 in this order from the DCS gas supply nozzle 30 side.

The O ₃ gas supply nozzle 4 will be described with reference to FIGS. The O ₃ gas supply nozzle 4 is a double tube including an inner tube 40 and an outer tube 41. The inner tube 40 is formed in a tubular shape whose front end is closed, and corresponds to a partition member that partitions the passage space for the oxidizing gas, here the O ₃ gas, and the atmosphere in which the wafer W is placed. The tube wall portion on the distal end side of the inner tube 40 is a porous material 40a having a thickness of 1 mm to 10 mm, for example, made of sintered quartz beads that are opaque and have high emissivity, and flows through the passage space. The treated gas is discharged to the outside of the inner tube 40 through the porous material 40a. The entire part of the porous material 40a may not be porous, and a part thereof may be a tube wall.

The outer tube 41 is formed in a cylindrical shape with a tube wall thickness of 1 mm to 4 mm covering the periphery of the portion of the porous material 40 a in the inner tube 40, for example, with quartz, and between the outer tube 41 and the inner tube 40. Is a buffer space (buffer space) for increasing the pressure of the O ₃ gas. On the lower surface of the outer tube 41, a plurality of discharge ports 42 having a diameter of 0.1 to 1 mm are formed at intervals of 1 mm to 10 mm in the length direction of the outer tube 41, and O ₃ gas whose pressure is increased by the buffer space is discharged from the discharge port. It is configured to be discharged from 42.

In the O ₃ gas supply nozzle 4, the proximal end side of the inner tube 40 is connected to a port 12 b provided on the outer peripheral wall of the processing container 1, the distal end side extends toward the center of the processing container 1, and the discharge from the outer tube 41 is performed. The outlets 42 are provided so as to straddle the region through which the wafer W passes when the turntable 2 is rotated. As shown in FIG. 2, one end side of an O ₃ gas supply pipe 43 is connected to the port 12 b, and an O ₃ gas supply source 44 is connected to the base end side of the O ₃ gas supply pipe 43. Further, the O ₃ gas supply pipe 43 is provided with a valve V43 and a flow rate adjusting unit M43 in this order from the O ₃ gas supply nozzle 4 side.

The two separation gas supply nozzles 34 and 37 are each configured by a nozzle configured in the same manner as the DCS gas supply nozzle 30, and the base end side of the separation gas supply nozzles 34 and 37 is a gas supply pipe penetrating the processing container 1. 35 and 38 are connected, and are connected to N ₂ gas supply sources 36 and 39. Above each of the separation gas supply nozzles 34 and 37, as shown in FIG. 2, convex portions 34a and 37a having a substantially fan-shaped planar shape are provided. The N ₂ gas discharged from the separation gas supply nozzle 34 spreads from the separation gas supply nozzle 34 to both sides in the circumferential direction of the processing container 1, and DCS is upstream of the rotation direction of the rotary table 2 of the DCS gas supply nozzle 30. A gas atmosphere and an O ₃ gas atmosphere are separated. Further, the N ₂ gas discharged from the separation gas supply nozzle 37 spreads from the separation gas supply nozzle 37 to both sides in the circumferential direction of the processing container 1, and on the downstream side of the rotation table 2 rotation direction of the DCS gas supply nozzle 30. The atmosphere of DCS gas and the atmosphere of O ₃ gas are separated.

As shown in FIGS. 1 and 2, a side ring 100, which is a cover body in which a gas flow path 101 forming a groove is formed, is disposed at a position slightly below the turntable 2 on the outer peripheral side of the turntable 2. Has been. Exhaust ports 61 are formed in the side ring 100 so as to be spaced apart from each other in the circumferential direction at two locations downstream of the DCS gas supply nozzle 30 and downstream of the O ₃ gas supply nozzle 4. As shown in FIG. 1, these exhaust ports 61 are connected to, for example, a vacuum pump 64 which is a vacuum exhaust mechanism by an exhaust pipe 63 provided with a pressure adjusting unit 65 such as a butterfly valve.

  Further, the film forming apparatus is provided with a control unit 90 including a computer for controlling the operation of the entire apparatus. A program for performing a film forming process described later is stored in the memory of the control unit 90. This program has a group of steps so as to execute the operation of the apparatus described later, and is installed by a storage medium such as a hard disk, a compact disk, a magneto-optical disk, a memory card, and a flexible disk.

  The operation of the above embodiment will be described. First, the gate valve is opened, and the rotary table 2 is intermittently rotated, and it is carried into the processing container 1 through the transfer port 15 by an external transfer arm (not shown), and the raising / lowering operation of the raising / lowering pins (not shown) is performed. Along with this, for example, five wafers W are sequentially placed on the turntable 2. Next, the gate valve is closed, the inside of the processing container 1 is pulled out by the vacuum pump 64 and the pressure adjusting unit 65, and the wafer W is loaded by the heating unit 7 while rotating the rotary table 2 clockwise, for example, at a rotation speed of 10 rpm. For example, it is heated to 400 ° C.

Subsequently, DCS gas having a flow rate of, for example, 10 to 300 sccm is supplied from the DCS gas supply nozzle 30. Further supplying the _{O 3} gas, for example at a flow rate of 1000sccm from the _{O 3} gas supply nozzle 4. Here, the O ₃ gas supplied will be described from the O ₃ gas supply nozzle 4. As described above, the inner tube 40 of the O ₃ gas supply nozzle 4 includes the porous material 40a made of quartz. Therefore, as shown in FIG. 6, when the wafer W is heated by the heating unit 7, the temperature of the porous material 40 a is increased by the heat irradiated from the heating unit 7 and the radiant heat radiated from the heated wafer W.

As shown in FIG. 7, the O ₃ gas supplied to the inner tube 40 flows through the inner tube 40 and is discharged out of the inner tube 40 through the gap between the porous materials 40a. At that time, the O ₃ gas is heated by the heat accumulated in the porous material 40a. At this time, since the gap between the porous materials 40a is narrow, the flow velocity is reduced, and the time until the flow from the inside of the inner tube 40 to the outside becomes long. Further, since the porous material 40a is used, the surface area with which the O ₃ gas is in contact is increased, and the efficiency of heat exchange between the O ₃ gas and the porous material 40a is increased. Therefore, the O ₃ gas is heated for a long time with high efficiency by the heated porous material 40a, and is heated to 350 to 400 ° C., for example. Further, the gas discharged from the inner tube 40 has a high pressure in the buffer space in the outer tube 41 and is discharged downward from the discharge port 42.

  Then, the rotary table 2 is rotated at a rotational speed of 10 rpm, for example. When attention is focused on one wafer W, the wafer W first passes under the DCS gas supply nozzle 30. The DCS gas discharged from the DCS gas supply nozzle 30 is heated and activated by heat from the rotary table 2 or the wafer W while adsorbing the wafer W while spreading on the rotary table 2 in the radial direction.

Then, the wafer W on which the DCS gas is adsorbed passes under the O ₃ gas supply nozzle 4 by the rotation of the turntable 2. The O ₃ gas is heated as it passes through the porous material 40a, and further supplied to the wafer W at a high speed by being pressurized by the buffer space. Therefore, the O ₃ gas is supplied to the wafer W in a highly active state, and the DCS gas adsorbed on the wafer W on the surface of the wafer W is rapidly oxidized. A good silicon oxide film (SiO ₂ film) is formed by the rapid progress of oxidation.
By continuing the rotation of the turntable 2 in this way, the adsorption of the DCS gas onto the surface of the wafer W and the oxidation of the components of the DCS gas adsorbed onto the surface of the wafer W are performed many times in this order, and the reaction product is produced. By laminating, a thin film of SiO ₂ film is formed.

According to the above-described embodiment, when the wafer W on which the DCS gas is adsorbed is heated and the O ₃ gas is supplied in the processing container 1, the O ₃ gas supply nozzle 4 is connected to the outer tube 41 and the inner tube 40. As a double pipe. Further, the tube wall portion at the distal end side portion of the inner tube 40 is constituted by the porous material 40 a, and the O ₃ gas is passed through the porous material 40 a heated by the radiant heat from the wafer W and the turntable 2. Since the porous material 40a has a narrow gap, the time until the O ₃ gas is discharged out of the inner tube 40 becomes longer, and the flow velocity becomes slower. The porous material 40a has a high heat capacity and a large contact area with the passing O ₃ gas. Thus heated is time increases heat transfer from the porous material 40a of the O ₃ gas is heated it is possible to heat storage of the heat of large amounts into the inner tube 40, the O ₃ gas can be efficiently heated. The O ₃ gas, whose flow velocity has once slowed down, is pressurized in the outer tube 41 and discharged from the discharge port 42 of the outer tube at a high flow rate. Accordingly, since highly active O ₃ gas can be supplied to the wafer W, a SiO ₂ film having a good film quality can be obtained.

The O ₃ gas is not necessary to use an apparatus for plasma the O ₃ gas can be the highly active state without performing excitation by power, which contributes to cost reduction of the substrate processing apparatus. In the present invention, the O ₃ gas may be excited, but in this case, it can be expected that the power for plasmatization can be reduced. It is also known that if the supply of the source gas—the supply of the O ₃ gas is one cycle, the SiO ₂ film is reformed using plasma in each cycle or in a cycle having a predetermined film thickness, for example. However, it can be expected that this modification treatment can be made unnecessary or that the power supplied to the plasma can be reduced. Furthermore, by using at least one of plasma conversion of O ₃ gas and modification treatment by plasma, further excellent film quality can be expected.

The DCS gas supply nozzle 30 may have the same configuration as the O ₃ gas supply nozzle 4. If the gas temperature is low when the gas is blown onto the wafer W, the temperature of the wafer W is lowered, and there is a possibility that the temperature in the wafer W surface becomes nonuniform and the film quality deteriorates. Therefore, when the DCS gas is discharged through the porous material 40a heated by heating the wafer W, a decrease in the wafer temperature can be prevented.

Even in the configuration in which the outer tube 41 is not provided in the O ₃ gas supply nozzle 4, the effect can be obtained because the O ₃ gas can be heated and supplied to the wafer W by the porous material 40 a. However, from the viewpoint of increasing the discharge amount per hour of the gas discharged from the O ₃ gas supply nozzle 4 and increasing the concentration of the gas immediately above the wafer W, it is preferable to increase the flow rate of the processing gas and supply it to the wafer W. In the above-described embodiment, the inner tube 40 is a double tube in which the periphery of the inner tube 40 is covered with the outer tube 41, and the processing gas discharged from the inner tube 40 is discharged in a buffer space in the outer tube 41 with an increased pressure. ing. Therefore, the flow rate of the processing gas discharged toward the wafer W can be increased, and the concentration of the gas immediately above the wafer W can be increased.

Further, in order to clean the film forming apparatus, a nozzle for supplying purge gas or cleaning gas is provided in the processing container 1, and the deposits are removed by supplying purge gas or cleaning gas into the processing container 1. At this time, if the cleaning gas or the purge gas is sprayed onto the inner tube 40, the porous material 40a may be scraped. Therefore, by covering the periphery of the porous material 40a in the inner tube 40 with the outer tube 41, the porous material 40a can be prevented from being scraped, and the replacement period of the gas supply unit can be lengthened.
The formation of the discharge ports 42 along the length direction of the outer tube 41 is either a configuration in which a plurality of discharge ports 42 are arranged or a configuration in which slits for discharging gas are formed in the length direction. May be.

[Another example of the first embodiment]
Moreover, you may provide the auxiliary | assistant heating part which heats the gas supply part shown in FIGS. 3-5 as another example of the substrate processing apparatus which concerns on 1st Embodiment. As such an example, a configuration in which an auxiliary heating unit 400 extending in the length direction of the O ₃ gas supply nozzle 4 is provided as shown in FIG. For example the auxiliary heating unit 400 is constituted by a heater comprising a resistance heating element of the rod-like, O ₃ above the gas supply nozzle 4, O ₃ gas supply width direction to the auxiliary heating unit 400 of the nozzle 4, the temperature measurement of a thermally electrode It arrange | positions in order of the part 401 and the auxiliary | assistant heating part 400, and it is provided so that it may protrude from the top-plate part 11 of the processing container 1. FIG. In addition, the connection part of the top-plate part 11, the auxiliary | assistant heating part 400, and the temperature measurement part 401 was abbreviate | omitted in FIG.

As shown in FIG. 9, for example, a temperature control unit 402 that performs PID control is provided, and the temperature measured by the temperature measurement unit 401 and the set temperature input from the control unit 90 are compared to compare the temperature of the auxiliary heating unit 400. You may comprise so that heating temperature may be controlled. With this configuration, the porous material 40a in the O ₃ gas supply nozzle 4 is heated by radiant heat from the wafer W and the turntable 2 as shown in FIG. 10, and the heating temperature is kept constant using the auxiliary heating unit 400. Therefore, the heating temperature of the porous material 40a can be stabilized and the temperature of the gas supplied to the wafer W can be stabilized. Furthermore, by using the auxiliary heating unit 400, the heating temperature of the processing gas in the O ₃ gas supply nozzle 4 can be adjusted to a wide range of temperatures.

  In the first embodiment, in order to set each gas at a different temperature when supplying a plurality of types of gases to the wafer W in the processing chamber 1, one processing gas is used as the gas. Is supplied to the wafer W through the porous material 40a from the passage space. However, in the present invention, each gas supply unit that supplies a plurality of processing gases is supplied from the gas passage space to the wafer W via the porous material 40a. For example, one gas supply unit is provided by the auxiliary heating unit 400. The other gas supply unit may be heated and the auxiliary heating unit 400 may not be provided, and each processing gas may be adjusted to a different temperature. Alternatively, the auxiliary heating unit 400 may be provided in all the gas supply units, and each processing gas may be set to be adjusted to a different temperature and supplied to the wafer W.

In addition, the processing gas is discharged through the porous material 40a by changing the emissivity of the bead body to be sintered or changing the size of the beads to change the time for the gas to pass through the gap between the porous materials 40a. The gas temperature can be changed. Therefore, when changing the supply temperature of each processing gas, the bead body radiation rate of each gas supply section may be changed, or the bead body size may be changed.
Further, the processing gas supply nozzle may be constituted by a rectangular tube-shaped inner tube 410 and an outer tube 411 as shown in the cross-sectional view of FIG.

[Second Embodiment]
An example in which the substrate processing apparatus according to the second embodiment is applied to a vertical heat treatment apparatus will be described. As shown in FIG. 12, the vertical heat treatment apparatus is formed in a quartz tube having both ends opened, and includes an inner reaction tube 111 that is a reaction tube to which a film forming gas is supplied. Is surrounded by a quartz cylindrical outer reaction tube 112 whose upper end is closed and whose lower end is open. Below the outer reaction tube 112, a stainless steel cylindrical manifold 115 is provided that is airtightly connected to the outer reaction tube 112 and the opening and is continuous with the outer reaction tube 112. A flange 117 is provided at the lower end of the manifold 115. Is formed. Further, a ring-shaped support portion 116 is formed inside the manifold 115, and the lower end of the inner reaction tube 111 is connected upright along the inner periphery of the support portion 116. The inner reaction tube 111, the outer reaction tube 112, and the manifold 115 correspond to processing containers.

  Further, the vertical heat treatment apparatus includes a heat insulator 113 that covers the outer reaction tube 112 from above, and a lower portion of the heat insulator 113 is fixed to a substrate 109 that fixes the reaction vessel 110. Inside the heat insulator 113, a heating unit 114 made of a resistance heating element is provided over the entire circumference.

  The opening 118 surrounded by the flange 117 in the manifold 115 is provided with a quartz circular lid 119 that opens and closes the opening 118, and the lid 119 is provided on the boat elevator 120 that raises and lowers the lid 119. It has been. A turntable 121 is provided on the upper surface side of the lid body 119, and the turntable 121 is provided to be rotatable around a vertical axis by a drive unit 122 provided below the boat elevator 120.

  Above the turntable 121, a heat insulating unit 123 is provided. Above the heat insulating unit 123, a wafer boat 102 as a substrate holder is provided. The wafer boat 102 includes a top plate 124a and a bottom plate 124b. A wafer 125 is inserted into a support column 125 that connects the top plate 124a and the bottom plate 124b to each other, and the wafer W is held in a shelf shape. A groove 126 is formed.

A DCS gas supply nozzle 127 and an O ₃ gas supply nozzle 128 serving as a gas supply unit are provided below the support 116 in the manifold 115. The DCS gas supply nozzle 127 extends horizontally and has a tip that opens as a gas supply port. The base end side of the DCS gas supply nozzle 127 is connected to a port 115 a formed in the manifold 115. Further, one end of a DCS gas supply pipe 131 is connected to the port 115a from the outer peripheral side of the manifold 115, and the other end side of the DCS gas supply pipe 131 is connected to a DCS gas supply source 132 via a valve V131 and a flow rate adjusting unit M131. It is connected.

The O ₃ gas supply nozzle 128 includes a horizontal portion and a vertical portion extending in the arrangement direction of the wafer W. The vertical portion is a double tube including an inner tube 140 and an outer tube 141 as shown in FIG. Yes. The portion corresponding to the height region including the arrangement region of the wafer W as viewed in the vertical direction in this example, in the distal end side of the inner tube 140, is opaque as in the O ₃ gas supply nozzle 4 shown in FIGS. A porous material 140a is obtained by sintering quartz beads, and a cylindrical outer tube 141 made of quartz is provided so as to cover the periphery of the porous material 140a portion of the inner tube 140. Further, on the wafer boat 102 side of the outer tube 141, discharge ports 142 for supplying O ₃ gas to the gaps between the wafers W are provided so as to correspond to the gaps between the wafers W, respectively.

The proximal end side of the O ₃ gas supply nozzle 128 is connected to a port 115 b formed in the manifold 115. One end of an O ₃ gas supply pipe 133 is connected to the port 115b from the outer peripheral side of the manifold 115, and the other end side of the O ₃ gas supply pipe 133 is supplied with an O ₃ gas via a valve V133 and a flow rate adjusting unit M133. Connected to source 134.

Further, one end side of an exhaust pipe 136 having a vacuum exhaust mechanism 135 connected to the other end side is connected to the upper side of the support part 116 in the manifold 115, and the upper side of the support part 116 in the manifold 115, that is, the outer reaction tube 112. The exhaust gas is exhausted from the gap with the inner reaction tube 111.
In such a vertical heat treatment apparatus, the wafer W is inserted into each holding groove 126 in the wafer boat 102, and the wafer W is heated to, for example, 780 ° C. by the heating unit 114. Then, exhaust is started, and DCS gas is supplied from the DCS gas supply nozzle 127. As a result, the inside reaction tube 111 is filled with DCS gas, and O ₃ gas is supplied from the O ₃ gas supply nozzle 128. Accordingly, the DCS gas adsorbed on the surface of the wafer W in the inner reaction tube 111 is oxidized by the O ₃ gas to become SiO ₂ and is deposited on the surface of the wafer W to form a SiO ₂ film.

At this time, when the wafer W is heated by the heating unit 114, the porous material 140a of the O ₃ gas supply nozzle 128 is also heated. Therefore O ₃ gas is passed through the porous material 140a is the O ₃ gas when fed into the inner reaction tube 111 is heated, it is possible to obtain the same effect to be supplied in a state where activity is enhanced.

[Third Embodiment]
Next, an example in which the substrate processing apparatus according to the third embodiment is applied to a single-wafer type film forming apparatus will be described. As shown in FIG. 14, the film forming apparatus includes a processing container 211. The processing container 211 includes a top plate 212 and a container main body 213, and is configured as a substantially flat cylindrical processing container. On the side wall of the container body 213, a loading / unloading port 214 for loading / unloading the wafer W and a gate valve 215 for opening / closing the loading / unloading port 214 are provided.

  A mounting table 221 for mounting a wafer W to be deposited is provided inside the processing chamber 211, and a circular recess that can accommodate the wafer W to be deposited is formed on the top surface of the mounting table 221. Yes. A rotation shaft 222 is provided at the center of the lower surface side of the mounting table 221. The rotation shaft 222 passes through the bottom plate of the container body 213, and at the lower end thereof, the mounting table 221 is rotated about the vertical axis and the mounting table. A driving unit 223 for moving up and down between a position where the film forming process 221 is performed and a transfer position where the wafer W is transferred is provided. In addition, 224 in FIG. 14 is a bearing part. In addition, a heating unit 207 corresponding to the mounting area of the wafer W on the upper surface side of the mounting table 221 is disposed between the bottom plate of the container body 213 and the mounting table 221.

  A DCS gas supply unit 203 that is a gas supply unit for discharging DCS gas to the wafer W is provided above the mounting table 221. The DCS gas supply unit 203 is provided, for example, above the mounting table 221 on the back side when viewed from the loading / unloading port 214 in the processing container 211 and at a position extending from above the center of the wafer W to above the periphery of the wafer W. . The DCS gas supply unit 203 includes a quartz partition member 240 for forming an elliptical space whose cross section extends in the radial direction of the wafer W. The partition member 240 may have a cylindrical shape or a rectangular cross section. In the partition member 240, the surface facing the mounting table 221, that is, the bottom surface of the partition member 240 is a porous material 240 a obtained by sintering opaque quartz beads. One end of a DCS gas supply pipe 241 is connected to the ceiling portion of the partition member 240, and a DCS gas supply source 242 is connected to the other end side of the DCS gas supply pipe 241 via a valve V241 and a flow rate adjustment unit M241. ing.

An O ₃ gas supply nozzle 204 that discharges an oxidizing gas from the side is provided in the gap between the mounting table 221 and the ceiling surface of the processing vessel 211. One end of an O ₃ gas supply pipe 243 is connected to the O ₃ gas supply nozzle 204, and the other end side of the O ₃ gas supply pipe 243 is connected to an O ₃ gas supply source 244 via a valve V243 and a flow rate adjusting unit M243. It is connected.

Further, an exhaust port 245 is formed so as to surround the periphery of the DCS gas supply unit 203. By exhausting from the exhaust port 245, the DCS gas and O ₃ supplied from the DCS gas supply unit 203 in the processing vessel 211 are formed. The O ₃ gas supplied from the gas supply pipe 243 is partitioned so as not to be mixed.

The film forming apparatus heats the wafer W mounted on the mounting table 221 and starts evacuation. Further, while rotating the wafer W around the vertical axis, DCS gas is supplied from above the wafer W and O ₃ gas is supplied. Since the exhaust is performed from the exhaust port 245, the DCS gas adheres only to a region surrounded by the exhaust port 245 on the surface of the wafer W. When the wafer W is rotated, the region where the DCS gas is adsorbed on the surface of the wafer W moves to a region surrounded by the exhaust port 245 and is exposed to the O ₃ gas supplied into the processing container.

As a result, the DCS gas adsorbed on the surface of the wafer W is oxidized to form a silicon oxide layer. By rotating the wafer W in this way, DCS gas and O ₃ gas are alternately supplied to the surface of the wafer W to form a SiO ₂ film. Also in such a film forming apparatus, the partition member 240 in the DCS gas supply unit 203 is heated by heat from the heating unit 207 that heats the wafer W and heat radiated from the heated wafer W. Therefore, the DCS gas can be heated and supplied to the wafer W by passing through the porous material 240a, so that the same effect can be obtained.

Further, the gas supply unit has a circular shower head structure whose plane is larger than that of the wafer W, and is configured to supply gas toward the entire surface of the wafer W. An exhaust port is provided around the gas supply unit in the processing container. Alternatively, a purge gas supply port may be provided outside the region surrounded by the exhaust port in the processing container, and an exhaust port for exhausting the purge gas may be provided in the processing container.
The present invention may also be used in a SiN film deposition apparatus that is performed by supplying DCS gas and NH ₃ gas to a wafer. Further, the etching apparatus is not limited to the film forming apparatus, and may be an etching apparatus that supplies the processing gas to the wafer W to etch the wafer W.

1 processing container 2 rotation table 7 heating unit 4 _{O 3} gas supply nozzle 30 DCS gas supply nozzle 40 inner tube 40a porous material 41 outer pipe 42 discharge ports W wafer

Claims (12)

In a substrate processing apparatus for performing processing by supplying a processing gas to a substrate heated in a processing container,
A placement section for placing the substrate in the processing container;
A heating unit for heating the substrate placed on the placement unit;
A gas supply unit provided in the processing container for discharging a processing gas sent from a processing gas supply source;
An exhaust part for exhausting the inside of the processing container,
The gas supply section includes a partition member that partitions a gas passage space, and a portion interposed between an atmosphere in which a substrate is placed and the passage space is made of a porous material,
A substrate processing apparatus configured to discharge a processing gas that has passed through the partition member to the outside of the partition member through the porous material.   The substrate processing apparatus according to claim 1, further comprising an auxiliary heating mechanism provided separately from the heating unit to heat the processing gas in the gas supply unit.   The substrate processing apparatus according to claim 1, wherein the partition member is made of quartz.   The substrate processing apparatus according to claim 1, wherein the partition member is a porous tube having a tube wall portion made of a porous material. The gas supply unit includes an outer member that forms a buffer space for increasing the pressure of the processing gas discharged from the porous material, between the atmosphere in which the substrate is placed and the porous material,
The substrate processing apparatus according to claim 1, wherein the outer member has a discharge port for discharging a processing gas into the atmosphere. The partition member is a porous tube whose tube wall portion is made of a porous material,
The substrate processing apparatus according to claim 5, wherein the outer member is an outer tube in which the discharge port is formed along a length direction thereof. A rotary table for revolving the mounting section before mounting the substrate;
A first processing gas supply unit for supplying a first processing gas to a region through which the placement unit passes and adsorbing a component of the first processing gas to the substrate;
The second process gas is provided separately from the first process gas supply unit in the rotation direction of the turntable and reacts with the component of the first process gas adsorbed on the substrate to form a reaction layer. A second processing gas supply unit for supplying a processing gas,
The substrate processing apparatus according to claim 4, wherein the gas supply unit including the porous tube corresponds to the second processing gas supply unit. The first processing gas is a gas containing a silicon compound,
The second processing gas is an oxidizing gas containing oxygen,
The substrate processing apparatus according to claim 7, wherein the process performed on the substrate is a process of forming a silicon oxide film. The processing container is a vertical reaction tube around which the heating unit is disposed,
The mounting portion is a substrate holder for holding a plurality of substrates in a shelf shape,
The porous tube is arranged in the vertical direction along the substrate holder in the reaction tube,
The substrate processing apparatus according to claim 4, further comprising an elevating mechanism for carrying the substrate holder in and out of the reaction tube and configured as a vertical heat treatment apparatus. A partition member provided in the processing container and partitioning a passage space for a gas sent from a processing gas supply source, and a portion interposed between the atmosphere in which the substrate is placed and the passage space is made of a porous material Using a substrate processing apparatus that performs processing by supplying a processing gas to a substrate heated in a processing container.
Placing the substrate in a processing vessel;
Heating the substrate placed in the processing vessel;
Discharging the processing gas sent from the processing gas supply source toward the substrate;
Evacuating the inside of the processing vessel,
The porous material is heated by heating the substrate,
The step of discharging the processing gas toward the substrate includes a step of discharging the processing gas that has passed through the partition member to the outside of the partition member through the heated porous material. Substrate processing method. The gas supply unit includes an outer member that forms a buffer space between an atmosphere in which the substrate is placed and the porous material,
11. The substrate processing method according to claim 10, wherein the step of discharging the processing gas toward the substrate includes a step of discharging the processing gas discharged from the porous material while increasing the pressure in the buffer space. . Using an auxiliary heating mechanism provided separately from the heating unit that heats the substrate,
The substrate processing method according to claim 10 or 11, wherein the processing gas in the gas supply unit is heated by the auxiliary heating unit before the step of discharging the processing gas toward the substrate.

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