JP2013040398A - Film forming method and film forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film forming apparatus that can improve the pressure in a processing space.SOLUTION: A putting table 3 that includes a putting region of a wafer W that is a substrate, and a top board part material 4 opposed to the putting table 3 are installed in a processing vessel 2; the putting table 3 is raised to the side of the top board part material 4 by a lifting mechanism 5; and a processing space S is formed between the putting table 3 and the top board part material 4. A projection part 43 is disposed at least at one of the outer region of the putting region of the putting table 3 and the top board part material 4, and the tip of the same comes in contact with the other when the processing space S is formed. Thus the clearance between the outer region and the top board part material 4 is restricted, and a gap 40 for exhaust of less than 1 mm is formed to enclose the putting region. Because the gap 40 is narrow, the reaction gas can be enclosed in the processing space S, and the pressure in the processing space is raised.

Description

  The present invention provides a film forming apparatus and a film forming apparatus for forming a thin film by laminating a plurality of reaction product layers by executing a cycle in which a first reaction gas and a second reaction gas are alternately supplied and exhausted a plurality of times. The present invention relates to a membrane method.

  As a film forming method in a semiconductor manufacturing process, a first reactive gas is adsorbed on a surface of a semiconductor wafer (hereinafter referred to as “wafer”) as a substrate in a vacuum atmosphere, and then a gas to be supplied is used as a second reactive gas. A process is known in which one or more atomic layers or molecular layers are formed by the reaction of both gases and this cycle is repeated many times to stack these layers and form a film on the wafer. It has been. This process is called, for example, ALD (Atomic Layer Deposition) or MLD (Molecular Layer Deposition), and the film thickness can be controlled with high accuracy according to the number of cycles, and the in-plane uniformity of the film quality is also achieved. It is a good technique that can cope with thinning of semiconductor devices.

  As an apparatus for carrying out this film forming method, for example, Patent Document 1 and Patent Document 2 have a configuration in which a wafer mounting table configured to be movable up and down in a vacuum container and a top plate member facing the mounting table are provided. Have been described. In this configuration, the mounting table is raised to form a processing space with the top plate member, and the reactive gas is supplied from the upper side of the central portion of the substrate, while the mounting table and the top plate are arranged along the circumferential direction of the mounting table. Unreacted reaction gas is exhausted from a gap formed between the members. Moreover, the film-forming apparatus of patent document 1 adjusts the residence time of the pressure in a process space, and a reactive gas by changing the clearance gap formed between the mounting stand and the top-plate member in the range of 1 mm-6 mm. Is configured to do.

As an example in which the film forming method is preferable, for example, a titanium nitride (TiN) film is formed. In this film forming process, for example, tetrachlorotitanium gas (TiCl) is used as the first reaction gas (raw material gas). ₄ gas) and ammonia gas (NH ₃ gas) is used as the second reaction gas. This TiN film is used as a wiring, an electrode, a barrier film, and the like, and is required to have a low specific resistance as a characteristic. The present inventors have proposed that the pressure in the processing space is improved in order to further improve the film characteristic. We are investigating a film-forming apparatus that can improve the process.

  Further, in Patent Document 3, in the sputtering apparatus, by adjusting the gap between the shield and the pedestal forming the processing space, the conductance of the flow path between the processing space and the outer space is adjusted, and the processing space Although a technique for controlling the internal pressure is described, the width of the gap is 8 mm to 33 mm, and even if this configuration is applied, the problem of the present invention cannot be solved. Further, Patent Document 4 describes a technique capable of shortening the purge time of residual gas by separating the reaction area and the transfer area. However, even if this configuration is applied, the problem of the present invention is described. It cannot be solved.

Japanese Patent Laying-Open No. 2010-84192 (FIG. 4, paragraph 0004) JP 2009-88473 A (FIG. 1) Japanese Patent Laid-Open No. 9-111447 (FIG. 1, FIG. 2, paragraph 0040) JP 2004-335892 A (FIG. 1, paragraph 0036)

  The present invention has been made under such circumstances, and an object of the present invention is to contain a reaction gas in a processing space formed between the mounting portion and the top plate member, thereby increasing the pressure in the processing space. It is to provide a technology that can.

For this reason, the film forming apparatus according to the present invention includes a first reaction gas and a second reaction gas that reacts with the first reaction gas to form a reaction product with respect to the substrate in the processing container. In a film forming apparatus for supplying and performing a film forming process,
A placement unit provided in the processing container and provided with a substrate placement region;
A top plate member provided so as to face the mounting portion and forming a processing space for the substrate with the mounting portion;
Between the position where the substrate is delivered to the mounting portion and the position where the mounting portion contacts the top plate member, the mounting portion can be moved up and down relatively with respect to the top plate member. An elevating mechanism for making the mounting portion relatively close to the top plate member during the film forming process and forming an exhaust gap in the circumferential direction of the substrate in the peripheral portion of the substrate or the outer region of the substrate;
It is provided between at least one of the mounting portion and the support portion that supports the mounting portion, and between the top plate member and the support portion that supports the top plate member, and is mounted by the lifting operation of the lifting mechanism. A buffer mechanism for correcting the relative posture of the mounting portion with respect to the top plate member and relaxing the contact pressure when one side of the mounting portion and the top plate member is biased to the other side, and
When the mounting portion and the top plate member are separated from each other, the corrected relative posture is to be restored so that the relative posture of the mounting portion with respect to the top plate member is corrected. A regulation mechanism to suppress the action of
A gas supply unit for supplying the first reaction gas and the second reaction gas to the processing space;
And an exhaust means for exhausting the processing space through the gap and the atmosphere in the processing container.

Further, the film forming method of the present invention includes a first reaction gas and a second reaction gas that reacts with the first reaction gas to form a reaction product with respect to the substrate in the processing container. In a film forming method of supplying and performing a film forming process,
The mounting portion provided in the processing container and provided with the substrate mounting region is placed on the top plate member with respect to the top plate member provided to face the mounting portion. A process of relatively raising to make contact,
By the buffer mechanism provided between at least one of the mounting portion and the support portion that supports the mounting portion, and between the top plate member and the support portion that supports the top plate member, the mounting portion and When one side of the top plate member is biased to contact the other side, the step of correcting the relative posture of the mounting portion with respect to the top plate member while relaxing the contact pressure;
When the mounting portion and the top plate member are separated from each other, the corrected relative posture is to be restored so that the relative posture of the mounting portion with respect to the top plate member is maintained in a corrected state. The process of suppressing the action to be performed by the regulation mechanism,
In a state in which the action of the relative posture to return to the original state is suppressed by this restriction mechanism, the mounting portion is brought relatively close to the top plate member, and the substrate is formed at the peripheral portion of the substrate or the outer region of the substrate. Forming a gap for exhaust in the circumferential direction of
Supplying the first reaction gas and the second reaction gas to the processing space;
And evacuating the processing space through the gap and the atmosphere in the processing container.

Furthermore, another invention of the present invention provides a first reaction gas and a second reaction gas that reacts with the first reaction gas to form a reaction product with respect to the substrate in the vacuum vessel. In a film forming apparatus for supplying and performing a film forming process,
A mounting portion provided in the vacuum container, and having a substrate mounting region;
A top plate member that is provided so as to face the mounting unit and forms a processing space for the substrate with the mounting unit;
Relative to the top plate member between the position where the substrate is transferred to the placement portion and the position where the placement portion is brought close to the top plate member to form the processing space. A lifting mechanism that lifts and lowers automatically,
Provided in at least one of the outer region of the placement region and the top plate member in the placement unit, and when the processing space is formed, the tip contacts with the other, so that between the outer region and the top plate member A projecting portion for forming a clearance of less than 1 mm for exhaust so as to restrict the separation distance and surround the placement region;
A gas supply unit for supplying the first reaction gas and the second reaction gas to the processing space;
And a vacuum evacuation unit for evacuating the processing space through the gap and the atmosphere in the vacuum vessel.

  According to the present invention, when the placement unit and the top plate member are separated from each other by the restriction mechanism, the film forming process is performed while maintaining the state in which the relative posture of the placement unit with respect to the top plate member is corrected. In some cases, the mounting portion is relatively close to the top plate member, and an exhaust gap is formed in the circumferential direction of the substrate at the peripheral portion of the substrate or the outer region of the substrate. As a result, a narrow gap having a uniform width along the circumferential direction can be formed with a predetermined size, so that the reactive gas can be contained in the processing space during the film forming process in the vacuum vessel. The pressure of is increased. According to another invention of the present invention, at least one of the outer region of the substrate placement region and the top plate member in the placement unit has a tip that contacts the other when the processing space is formed. Since the protrusion for restricting the separation distance between the outer region and the top plate member is provided, a clearance of less than 1 mm for exhaust is formed so as to surround the placement region when the processing space is formed. For this reason, since the processing space can be separated from the exhaust space in the vacuum chamber during the film forming process, the reaction gas can be contained in the processing space, and the pressure in the processing space is increased.

It is a vertical side view which shows 1st Embodiment of the film-forming apparatus concerning this invention. It is an expanded vertical side view which shows the buffer mechanism provided in the said film-forming apparatus. It is an expanded vertical side view which shows the buffer mechanism provided in the said film-forming apparatus. It is an expanded vertical side view which shows the mounting base and top-plate member of the said film-forming apparatus. It is the bottom view which looked at the top plate member from the mounting base. It is process drawing which shows an example of the film-forming method performed with the said film-forming apparatus. It is a vertical side view for demonstrating the effect | action of the said film-forming apparatus. It is a vertical side view for demonstrating the effect | action of the said film-forming apparatus. It is a characteristic view for demonstrating the effect | action of the said film-forming apparatus. It is a characteristic view which shows the supply timing of the source gas supplied to the said film-forming apparatus, reducing gas, and purge gas, and the pressure in process space. It is an expanded vertical side view which shows the mode of the gas flow in the process space comprised by the said mounting base and a top-plate member. It is a vertical side view for demonstrating the effect | action of the said film-forming apparatus. It is a vertical side view for demonstrating the effect | action of the said film-forming apparatus. It is a vertical side view for demonstrating the effect | action of the said film-forming apparatus. It is a vertical side view which shows the other example of the said film-forming apparatus. It is a vertical side view for demonstrating the effect | action of the film-forming apparatus shown in FIG. It is a vertical side view for demonstrating the effect | action of the film-forming apparatus shown in FIG. It is a vertical side view which shows the other example of the said film-forming apparatus. It is a vertical side view which shows the other example of the said film-forming apparatus. It is a vertical side view which shows the other example of the said film-forming apparatus. It is a vertical side view which shows the other example of the said film-forming apparatus. It is a vertical side view which shows the other example of the said film-forming apparatus. It is a vertical side view which shows the other example of the said film-forming apparatus. It is a vertical side view which shows the other example of the said film-forming apparatus. It is a vertical side view which shows 2nd Embodiment of the film-forming apparatus concerning this invention. It is a vertical side view which shows a push screw and a nut. It is a top view which shows a drive member and a raising / lowering mechanism. It is process drawing which shows an example of the film-forming method of this invention. It is a vertical side view which shows the effect | action of the film-forming apparatus. It is a vertical side view which shows the effect | action of the film-forming apparatus. It is a vertical side view which shows the effect | action of the film-forming apparatus. It is a vertical side view which shows the effect | action of the film-forming apparatus. It is a vertical side view which shows the effect | action of the film-forming apparatus. It is a vertical side view which shows the effect | action of the film-forming apparatus. It is a vertical side view which shows the other example of 2nd Embodiment of the film-forming apparatus. It is a vertical side view which shows the further another example of 2nd Embodiment of the film-forming apparatus. It is a vertical side view which shows the further another example of 2nd Embodiment of the film-forming apparatus. It is a vertical side view which shows 3rd Embodiment of the film-forming apparatus concerning this invention. It is a flowchart which shows the effect | action of the film-forming apparatus of 3rd Embodiment. It is a vertical side view which shows the effect | action of the film-forming apparatus. FIG. 6 is a characteristic diagram showing the results of Example 1. FIG. 6 is a characteristic diagram showing the results of Example 2.

(First embodiment)
First, the film forming apparatus 1 according to the first embodiment of the present invention will be described. The first embodiment corresponds to the second independent claim (claim 6). As shown in FIG. 1, the film forming apparatus 1 of this example includes, for example, a processing container 2 that forms a vacuum container having a substantially circular planar shape, and a mounting table 3 that forms a mounting part provided in the processing container 2. And a top plate member 4 which is provided at a position facing the mounting table 3 and forms a processing space between the mounting table 3 and the mounting table 3.

The mounting table 3 is made of a ceramic such as aluminum nitride (AlN) or quartz glass (SiO ₂ ), or a metal such as aluminum (Al) or Hastelloy, and is formed in a flat disk shape, for example. The surface of the mounting table 3 is configured as a mounting surface for a wafer W, which is a substrate. The mounting surface is formed to be slightly larger than, for example, a wafer W having a diameter of 300 mm, and an area on which the wafer W is mounted is formed. It corresponds to the mounting area. In addition, a heater 31 serving as a heating unit is embedded in the mounting table 3 in order to raise the temperature of the wafer W to the film forming temperature. The heater 31 is composed of, for example, a sheet-like resistance heating element so that the wafer W on the mounting table 3 can be heated to, for example, about 350 ° C. to 500 ° C. with power supplied from a power supply unit (not shown). It has become. Furthermore, if necessary, an electrostatic chuck (not shown) may be provided in the mounting table 3, and the wafer W on the mounting table 3 may be attracted and held by electrostatic suction.

  The mounting table 3 is supported by, for example, a lower-surface-side central portion by a columnar support member 32, and this support member 32 is connected to the processing container 2 through a through hole 22 provided in the bottom wall 21 of the processing container 2. The flange portion 33 is connected to the lower end of the flange portion. Between the bottom wall 21 and the flange portion 33, a bellows body 34 for raising and lowering the support member 32 by the elevating mechanism 5 is provided while maintaining airtightness in the processing container 2.

  The elevating mechanism 5 elevates the mounting table 3 between the transfer position of the wafer W and the processing position above the transfer position. This processing position is a position where a processing space is formed between the mounting table 3 and the top plate member 4 as described later. In this example, the elevating mechanism 5 is connected to the first elevating mechanism 5A connected to one end side in the left-right direction (X direction in FIG. 1) of the flange portion 33 and the other end side in the left-right direction of the flange portion 33. And a second lifting mechanism 5B. These first and second elevating mechanisms 5A and 5B are configured in the same manner, and each has a ball screw 51 extending in the vertical direction (Z direction in FIG. 1), and a driver 52 moving in the vertical direction along the ball screw 51. And.

  The driving body 52 is provided with a plate-like driving member 53, and the driving member 53 is connected to the flange portion 33 via the buffer mechanism 6. In the figure, reference numeral 54 denotes a motor that rotates the ball screw 51, and the motor 52 and the driving member 53 are configured to move in the vertical direction when the ball screw 51 is rotated by the motor 54. When the inside of the processing container 2 is set to a vacuum atmosphere, as described later, the mounting table 3 moves up and down via the buffer mechanism 6, the flange portion 33, and the support member 32 as the driving member 53 moves. Freely configured.

  As shown in FIGS. 2 and 3, the buffer mechanism 6 is configured by laminating a plurality of disc springs 61 constituting an elastic member in the vertical direction. The disc spring 61 is formed in a ring shape that opens while the central portion swells, and is laminated in combination so that the swelled portions face each other. In this example, the four disc springs 61 are provided at, for example, three to six positions in the circumferential direction between the upper surface of the flange portion 33 and the lower surface of the driving member 53 whose planar shape is a ring shape. The mounting table 3 is provided so as to be able to swing with respect to the driving member 53 which is a supporting part thereof. In other words, the mounting table 3 can be tilted in any direction by the buffering action of the disc spring 61. Therefore, when the mounting table 3 is biased to contact with the top plate member 4 via the projection 43 described later. In addition, the posture of the mounting table 3 is corrected, and a state in which a uniform load is applied to each protrusion 43 is obtained. In FIG. 2, reference numeral 63 denotes a rod-shaped guide member whose lower end is fixed to the upper surface of the flange portion 33. The guide members 63 are passed through the respective openings 62 of the plurality of disc springs 61, so that the disc springs 61 are stacked on the flange portion 33 in a state where positional deviation in the left-right direction is suppressed. It is like that.

  The upper end side of the guide member 63 is configured to be able to move up and down in a hole 53 a formed in the drive member 53. 1 to 3 is a positioning mechanism for the flange portion 33 provided on the lower side of the flange portion 33. As shown in FIGS. 1 to 3, a protrusion 55 a is formed on the upper surface of the positioning mechanism 55, while a recess 33 b corresponding to the protrusion 55 a is formed on the lower surface of the flange portion 33. . Further, a protrusion 33 a is formed on the upper surface of the flange portion 33, while a recess 53 b corresponding to the protrusion 33 a is formed on the lower surface of the drive member 53.

  Here, the height position of the mounting table 3 will be described. The height position shown in FIGS. 1 and 2 indicates that the wafer W is transferred to the mounting table 3 when the inside of the processing container 2 is set to an air atmosphere. The delivery position to perform. At this time, the atmospheric atmosphere refers to a pressure state before the inside of the processing container 2 is evacuated, as will be described later in the film forming process. In this state, the weight of the mounting table 3 is applied to the flange portion 33, and the height of the flange portion 33 is determined by fitting the concave portion 33 b of the projection portion 55 a of the positioning mechanism 55. It has become. At this time, no load is applied to the buffer mechanism 6, and the upper end of the guide member 63 is configured to be positioned in the hole 53 a of the drive member 53 as shown in FIG. 2.

  Moreover, the height position shown with a dotted line in FIG. 1 is the height position of the mounting table 3 when the inside of the processing container 2 is set to a vacuum atmosphere when the mounting table 3 is in the delivery position. When the inside of the processing container 2 is in a vacuum atmosphere, the flange portion 33 receives atmospheric pressure and is drawn toward the processing container 2 side, and the mounting table 3 slightly rises from the position of the atmospheric atmosphere.

  As the flange portion 33 is raised, the protrusion 33a on the upper surface of the flange portion 33 is fitted into the recess 53b on the lower surface of the drive member 53, as shown in FIG. At this time, the buffer mechanism 6 is loaded and contracted in the vertical direction, and the upper end of the guide member 63 moves upward in the hole 53a of the drive member 53 as shown in FIG. Here, for example, the delivery position of the mounting table 3 when the inside of the processing container 2 is in an air atmosphere is set to a position lower by, for example, 2 mm than when the inside of the processing container 2 is in a vacuum atmosphere, and the height shown in FIGS. The shapes of the drive member 53, the guide member 63, and the positioning mechanism 55 are set so that the relationship can be maintained.

  Thus, the buffer mechanism 6 is provided between the mounting table 3 and the support portion that supports the mounting table 3 so that the mounting table 3 can swing with respect to the support portion. Here, the disc spring 61 is made of, for example, a metal such as stainless steel or spring steel. When an example of the size of the disc spring 61 is increased, the outer diameter L1 is 18 mm, the inner diameter L2 is 9.2 mm, and the height L3 in an unloaded state. Is 1.20 mm (JIS B2706 L18).

  Further, the mounting table 3 includes a plurality of lifting pins 35 for transferring the wafer W between the mounting table 3 and an external transfer mechanism (not shown). The elevating pin 35 is movable up and down between a position where the upper end protrudes from the surface of the mounting table 3 and a position below the surface by an elevating part 36 provided outside the processing container 2, for example. It is configured. In the figure, reference numeral 37 denotes a bellows body for raising and lowering the elevating pins 35 while maintaining the airtightness in the processing container 2.

  Then, the ceiling part 23 of the processing container 2 is demonstrated. The ceiling portion 23 in this example is formed of, for example, aluminum, alumina, or the like, and is configured as a protruding portion in which a portion facing the mounting surface of the mounting table 3 protrudes downward, and this protruding portion is the present invention. This corresponds to the top plate member 4. The bottom surface of the top plate member 4 is configured to be gradually deepened from the peripheral edge toward the central portion, and thus the concave portion 41 is formed on the bottom surface of the top plate member 4. The recess 41 is opened in a circular shape having a diameter larger than that of the wafer W so as to cover, for example, the entire wafer W placed on the mounting table 3. Further, it is configured as a flat portion 42 protruding further to the mounting table 3 side. The shape and size of the recess 41 are set so as to form a processing space around the wafer W on the mounting table 3 when the mounting table 3 is located at the processing position.

  As shown in FIG. 4, a plurality of, for example, 3 to 6 protrusions 43 are spaced apart from each other along the circumferential direction of the placement region 30 on the lower surface of the flat portion 42 of the top plate member 4. Is provided. When the processing space is formed, the protrusion 43 contacts the outer region of the mounting table 3, thereby regulating the separation distance between the outer region and the top plate member 4. It is provided to form a narrow gap 40 of less than 1 mm for exhaust so as to surround. As long as the protrusion 43 is configured to form a gap for uniformly exhausting the atmosphere in the processing space along the circumferential direction of the mounting table 3, the shape, the number, and the arrangement interval are not limited. 5 is a schematic bottom view when the top plate member 4 is viewed from the mounting table 3 side, and FIG. 4 shows a flat portion 42 provided with the protrusion 43 and a flat portion 42 not provided. ing.

  Here, as will be apparent from the examples described later, the gap 40 has a greater effect of containing the reactive gas in the processing space as the separation distance h between the mounting table 3 and the top plate member 4 becomes smaller. Thus, the pressure in the processing space can be increased. On the other hand, if the distance h is too small, the exhaust force is reduced. Therefore, the distance h is preferably 0.1 mm or more and less than 1 mm.

A gas supply unit 7 for supplying a reaction gas to the processing space is provided at the center of the top plate member 4, and the gas supply path 70 formed in the gas supply unit 7 is a top plate member. 4 is configured to communicate with a gas supply port 44 formed in the central portion of 4. The gas supply unit 7 includes a first gas supply path 71 for the first reactive gas, a second gas supply path 72 for the second reactive gas, and a third gas supply path 73 for the purge gas. Are connected to each other. Hereinafter, a case where a titanium nitride film (TiN film) is formed will be described as an example. Each of the first to third gas supply paths 71 to 73 is a flow rate adjusting unit including a flow rate adjusting valve, an opening / closing valve, and the like. 71a, 72a, the source 71b of the raw material gas, for example, TiCl ₄ gas as the first reaction gas via 73a, the source 72b of the reducing gas, eg NH ₃ gas as the second reaction gas, _{N 2} gas is a purge gas Are respectively connected to the supply source 73b. The flow rate adjusters 71a, 72a, 73a are configured to control the supply and stop timings of various gases based on commands from the controller 100 described later.

  Further, an exhaust part 24 is formed in the processing container 2 on the side of the top plate member 4. In this example, the exhaust part 24 is formed between the lower container 25 and the ceiling part 23 of the processing container 2 and is connected to a vacuum pump 27 serving as a vacuum exhaust means via an exhaust path 26 having a valve V. Has been. In this way, the internal atmosphere of the processing space formed by the mounting table 3 and the top plate member 4 is evacuated by the vacuum pump 27 through the gap 40 and the atmosphere in the processing container 2.

  Further, in the film forming apparatus 1 described above, a transfer port 28 for carrying the wafer W in and out of the processing container 2 by an external transfer mechanism (not shown) is formed on the side wall of the lower container 25. 28 is configured to be freely opened and closed by a gate valve 29.

  The film forming apparatus 1 having the above-described configuration includes the gas supply operation from the gas supply unit 7 described above, the lifting operation of the mounting table 3 by the lifting mechanism 5 (5A, 5B), and the processing container 2 by the vacuum pump 27. A control unit 100 that controls the exhaust operation, the heating operation by the heater 31, and the like is provided. The control unit 100 includes, for example, a computer including a CPU and a storage unit (not shown). In the storage unit, steps necessary for performing film formation on the wafer W by the film formation apparatus 1 ( A program having a group of instructions) is stored. This program is stored in a storage medium such as a hard disk, a compact disk, a magnetic optical disk, or a memory card, and installed in the computer therefrom.

Subsequently, the operation of the film forming apparatus 1 according to the present embodiment will be described with reference to FIG. First, in the processing container 2 in an atmospheric atmosphere (atmosphere before the processing container 2 is evacuated), the mounting table 3 is positioned at the delivery position and evacuated by the vacuum pump 27 (step S1). Thereby, since the upward load is applied to the processing container 2 side due to the atmospheric pressure, the mounting table 3 is attracted to the processing container 2 side, and is raised by, for example, 2 mm from the height position of the mounting table 3 in the air atmosphere. Then, the transfer port 28 is opened, the wafer W is loaded into the processing container 2 by an external transfer mechanism, and the wafer W is delivered onto the mounting region 30 of the mounting table 3 by cooperating with the lifting pins 35 ( Step S2).
Next, after closing the transport port 28, the first and second lifting mechanisms 5A and 5B are used to raise the mounting table 3 to the processing position, as shown in FIG. A processing space S is formed between them (step S3). This processing position is a position where the outer region of the mounting table 3 abuts on the protrusion 43. At this time, the mounting table 3 has the first and second elevating mechanisms 5A, because the flange 33 is drawn toward the processing container 2 side by making the inside of the processing container 2 a vacuum atmosphere as described above. By 5B, it raises via the drive member 53, the buffer mechanism 6, the flange part 33, and the support member 32. As shown in FIG. For this reason, the motors 54 of the first and second elevating mechanisms 5A and 5B are synchronized with each other, and are raised in a state where the rising amounts are uniform.

  Thus, after the mounting table 3 is brought into contact with the protrusion 43, the drive member 53 is slightly raised by, for example, 1 mm as shown in FIG. 8 (step S4). As a result, a force acts in the direction in which the top plate member 4 approaches the mounting table 3 at the position where the processing space is formed.

  Here, the relationship between the amount of lift of the drive member 53 of the elevating mechanisms 5A and 5B and the load will be described with reference to FIG. In FIG. 9, the horizontal axis represents the amount by which the driving member 53 is lifted in a vacuum atmosphere. 0 mm is the height position of the driving member 53 when the mounting table 3 is in the transfer position in the vacuum atmosphere, and 42 mm is the mounting table 3. Corresponds to the height position of the drive member 53 at the processing position (position where it abuts against the protrusion 43). In FIG. 9, the vertical axis represents the load, ◆ represents the load due to the reaction force of the bellows body 34, ■ represents the load due to the reaction force of the buffer mechanism 6, and ▲ represents the combined load.

  The bellows body 34 is fully extended at the delivery position in a vacuum atmosphere, and the load due to the reaction force is 0 N. However, since the contraction amount increases as the driving member 53 moves up, the reaction force gradually increases. The load increases. Further, the reaction force of the buffer mechanism 6 is obtained by (reaction force per one disc spring 61) × (number of disc springs 61). The disc spring 61 is in a contracted state in a vacuum atmosphere as shown in FIG. 3, and the load due to the reaction force of the buffer mechanism 6 remains about 475 N until the mounting table 3 is raised to the processing position. The combined load is an upward load due to atmospheric pressure, a load due to a downward reaction force due to the bellows body 34, a load due to a downward reaction force due to the buffer mechanism 6, and a downward load due to the weight of the mounting table 3, Desired.

Composite load = load due to atmospheric pressure − [(weight of mounting table 3) + (reaction force of bellows body 34) + (reaction force of buffer mechanism 6)]
The combined load thus determined is the largest because the reaction force by the bellows body 34 is 0 N at the delivery position in a vacuum atmosphere, and a combined load of about 230 N is applied to the drive member 53. For this reason, the height position of the mounting table 3 is fixed by applying a brake to the first and second elevating mechanisms 5A and 5B. This brake is a mechanism such as an electromagnetic brake of the motor 54 that stops the movement of the ball screw. Then, as the mounting table 3 is raised from the delivery position to the vicinity of the processing position, the resultant load gradually decreases as the reaction force by the bellows body 34 increases. In this way, the load balance state in which the combined load is 0 N is brought before the mounting table 3 comes into contact with the protrusion 43. Thereafter, when the drive member 53 is further raised, the height position of the mounting table 3 is regulated by the protrusion 43, so that the disc spring 61 of the buffer mechanism 6 is extended, and the downward reaction by the buffer mechanism 6 is suppressed. The force gradually decreases, and the resultant load gradually increases as shown in FIG.

  This combined load is applied between the mounting table 3 and the protrusion 43. For example, when the mounting table 3 is made of ceramics such as aluminum nitride, the load resistance is 700 N or less. Therefore, the distance by which the driving member 53 is raised after the mounting table 3 is brought into contact with the protrusion 43 is as follows: For example, the combined load is set to about 2 to 3 mm so as to be smaller than the load resistance.

  After the mounting table 3 is brought into contact with the protrusion 43 in this way, the driving member 53 is raised by a predetermined amount, thereby relaxing the contact pressure when the mounting table 3 contacts the protrusion 43 by the buffer mechanism 6. The mounting table 3 can be reliably pressed against all the protrusions 43. Thereby, a narrow gap 40 having a uniform width (distance between the mounting table 3 and the top plate member 4) in the circumferential direction of the mounting table 3 between the mounting table 3 and the top plate member 4 at the processing position, It can be formed along the circumferential direction of the mounting table 3.

  Thus, when the inside of the processing container 2 is evacuated to, for example, 13.3 Pa (0.1 Torr) and the temperature is raised to 350 ° C. to 650 ° C. that is the film forming temperature of the wafer W by the heater 31, the film forming process is started. . In a so-called ALD process using the film forming apparatus 1 according to the present embodiment, film formation is performed based on, for example, a gas supply sequence shown in FIG. In these figures, the horizontal axis represents time, and the vertical axis schematically represents the gas supply amount and the pressure in the processing space S.

First, a source gas (TiCl ₄ gas) is supplied into the processing space S through the first gas supply path 71 and is adsorbed to the wafer W on the mounting table 3 (adsorption process) (step S5). . By supplying the raw material gas, the pressure in the processing space S rises to, for example, 6665 Pa (50 Torr). Therefore, the pressure difference between the processing space S and the exhaust part 24 increases, and the source gas supplied into the processing space S is processed through the gap 40 between the mounting table 3 and the top plate member 4. It tries to flow out toward the exhaust part 24 whose pressure is lower than that of the space S.

  As a result, in the processing space S, as shown in FIG. 11, the source gas supplied from the gas supply port 44 provided on the upper side of the central portion of the wafer W spreads outward in the processing space S. However, the surface of the wafer W flows in the radial direction toward the gap 40, and during this time, it is adsorbed on the surface of the wafer W to form a Ti molecular layer.

Thus, the source gas is supplied for a predetermined time and the supply of the source gas is stopped. Thereby, since the source gas in the processing space S is exhausted, the pressure in the processing space rapidly decreases as shown in FIG. In this way, from the third gas supply path 73 at a timing when the pressure in the processing space S becomes substantially the same pressure as before the introduction of the raw material gas, for example, when a predetermined time, for example, 0.03 seconds has elapsed since the supply of the raw material gas is stopped. The supply of the purge gas (N ₂ gas) is started and the purge process is performed (step S6). Thus, the purge gas flows in the processing space S from the central portion toward the peripheral region on the surface of the wafer W, and together with the raw material gas staying in the processing space S, the exhaust portion 24 through the gap 40. It is exhausted towards. By supplying the purge gas, the pressure in the processing space S rises to, for example, 6665 Pa (50 Torr) according to the supply flow rate of the purge gas.

Then, the supply of the purge gas is stopped at the timing when the source gas staying in the processing space S is exhausted together with the purge gas. As a result, the pressure in the processing space S drastically decreases as shown in FIG. 10, so that the pressure in the processing space S becomes substantially the same as that before the introduction of the raw material gas, for example, a predetermined time after the supply of the purge gas is stopped. For example, at the timing when 0.03 seconds have passed, the reducing gas (NH ₃ gas) supply is started from the second gas supply path 72 to perform the reducing process (step S7). Thereby, the reducing gas flows in the processing space S from the central portion toward the peripheral region on the surface of the wafer W, and the source gas adsorbed on the surface of the wafer W is reduced to form a TiN molecular layer. Is done. The reducing gas in the processing space S is exhausted from the processing space S to the exhaust unit 24 through the gap 40, but the pressure in the processing space S is changed to the supply flow rate of the reducing gas by the supply of the reducing gas. In response, for example, it rises to 6665P (50 Torr).

Thus, after supplying the reducing gas into the processing space S for a predetermined time, the supply of the reducing gas is stopped. As a result, as shown in FIG. 10, the pressure in the processing space S suddenly decreases and the pressure in the processing space S becomes substantially the same as that before the introduction of the raw material gas, for example, a predetermined time after the supply of the reducing gas is stopped. For example, at the timing when 0.03 seconds have elapsed, the supply of N ₂ gas, which is a purge gas, is started again, and a purge process for purging the reducing gas staying in the processing space S is performed (step S8). As a result, the reducing gas remaining in the processing space S is exhausted together with the purge gas toward the exhaust unit 24 through the gap 40.

  Then, the four steps from step S5 to step S8 described above are defined as one cycle, the cycle is repeated a predetermined number of times, for example, 50 to 1000 times, and the TiN molecular layer is multilayered, for example, 3 to 3. The formation of a film having a thickness of 20 nm is completed (step S9). Note that FIG. 10 schematically shows a pressure pattern in the processing space S in each step for convenience of explanation, and does not show a strict pressure in the processing space S.

  When the film forming process is completed, the gas supply is stopped, and the mounting table 3 on which the wafer W is mounted is lowered to the delivery position while the inside of the processing container 2 is maintained in a vacuum atmosphere (step S10). Then, the wafer W is unloaded by an external transfer mechanism through a path opposite to that at the time of loading, and a series of film forming operations is completed (step S11). When there is no wafer W to be processed next, the inside of the processing container 2 is returned to the atmospheric atmosphere (the state before evacuation), and the mounting table 3 is positioned at the delivery position of the atmospheric atmosphere. At this time, when the inside of the processing container 2 is returned to the air atmosphere, the pulling of the mounting table 3 to the top plate member 4 side by the vacuum atmosphere is released. To do.

  Here, in a state in which the supply of gas into the processing space S is stopped and all the gas is exhausted, the pressure in the processing space S and the pressure in the exhaust unit 24 are the same, but each gas supply The time during which the gas supply between the processes is stopped is as short as about 0.03 seconds, and the next gas is immediately introduced. Therefore, there is almost no risk of gas entering the processing space S from the exhaust part 24. .

  According to the above-described embodiment, when the processing space S is formed by the mounting table 3 and the top plate member 4, a narrow gap 40 of less than 1 mm is provided between them along the circumferential direction of the mounting table 3. It is formed. For this reason, as will be apparent from the embodiments described later, since the gas can be contained in the processing space S, the pressure difference in the processing space S is increased by increasing the differential pressure between the processing space S and the exhaust part 24. Can be high. In addition, since gas can be contained in this way, the amount of gas used can be reduced.

  At this time, a protrusion 43 is provided on the lower surface of the top plate member 4, and the mounting table 3 is brought into contact with the protruding portion 43 to be stopped so as to regulate the separation distance between the mounting table 3 and the top plate member 4. ing. For this reason, a narrow gap 40 having a width (distance between the mounting table 3 and the top plate member 4) of less than 1 mm can be formed uniformly in the circumferential direction of the mounting table 3. Thereby, in the processing space S, the exhaust amount is aligned in the circumferential direction of the mounting table 3, so that the gas supply state to the wafer W is aligned over the surface of the wafer W. As a result, a process with good in-plane uniformity can be performed, and a thin film with uniform film characteristics such as film thickness, film quality, and specific resistance can be obtained over the wafer W plane.

  Further, since the pressure in the processing space S can be increased, when a metal film used for wiring, electrodes, barrier films, etc., such as a TiN film, is formed, as will be apparent from the examples described later. A metal film having a low specific resistance can be formed. The reason for this is that by increasing the pressure in the processing space S, the total amount of gas supplied to the wafer W per fixed time can be increased. For example, when introducing the reducing gas, the adsorbed source gas It is presumed that the gas that contributes to the reduction of the amount increases and the film quality can be improved. Furthermore, since the total amount of gas supply per fixed time is large as described above, the gas supply time can be shortened, and the recipe can be shortened.

  Furthermore, since the differential pressure between the processing space S and the exhaust part 24 can be increased, the flow rate of the gas flow from the processing space S to the exhaust part 24 increases, and the gas flow from the exhaust part 24 to the processing space S increases. Diffusion can be suppressed.

  In the above-described embodiment, since the buffer mechanism 6 is provided, the narrow gap 40 of less than 1 mm can be formed with high accuracy along the circumferential direction of the mounting table 3. That is, after raising the mounting table 3 to the processing position (position where it abuts against the protruding portion 43), the driving member 53 is further lifted slightly, so that the mounting table 3 is reliably moved to all the protruding portions 43. This is because it can be pressed against the lens 43. At this time, when the drive member 53 is raised, the buffer mechanism 6 extends as shown in FIG. 8, so that the contact pressure when the mounting table 3 comes into contact with the protrusion 43 is relieved accordingly. In the configuration in which the buffer mechanism 6 is not provided, if the mounting table 3 is raised to the processing position and then the driving member 53 is further raised, the mounting table 3 itself tends to rise, so that a large load is applied to the protrusion 43. The mounting table 3 may be deformed or damaged.

  Further, the buffer mechanism 6 is configured by, for example, a disc spring 61 and is configured so that the mounting table 3 can swing with respect to the driving member 53 that is a support portion, and thus the mounting table 3 is lifted in an inclined state. Even in this case, the mounting table 3 can be reliably pressed against all the protrusions 43.

  For example, as shown in FIG. 12, when the mounting table 3 rises in a tilted state, when the mounting table 3 moves to the processing position, as shown in FIG. However, it will be in the state which does not contact the other projection part 43. FIG. When the driving member 53 is raised in this state, the mounting table 3 can swing with respect to the driving member 53 by providing the buffer mechanism 6, so that the mounting table 3 swings in an area not in contact with the protrusion 43. As the drive member 53 is raised, the inclination is adjusted while moving. For this reason, if the distance h1 between the protrusion 43 that is not in contact with the mounting table 3 is equal to or smaller than the moving distance h2 of the driving member 53, the driving member 53 is raised by h2 as shown in FIG. The mounting table 3 can be reliably pressed against all the protrusions 43. As described above, by providing the buffer mechanism 6, even if the mounting table 3 is lifted in a tilted state, an excessive force is not applied between the mounting table 3 and the projecting portion 43. Thus, the mounting table 3 can be reliably pressed against all the protrusions 43, and a narrow gap 40 can be formed between the mounting table 3 and the top plate member 4 with high accuracy. At this time, by using a combination of a plurality of disc springs 61 as the elastic member, a large load can be supported with a compact configuration, so that space saving can be achieved.

  As described above, the amount of increase when the driving member 53 is further lifted after the mounting table 3 is raised to the processing position is the combined load (the amount of the mounting table 3 and the protrusion 43 is increased). Since the load applied in the meantime increases, it is determined in consideration of the expected degree of inclination of the mounting table 3 and the load resistance of the mounting table 3.

  Subsequently, another example of the film forming apparatus 1 of the present invention will be described with reference to FIGS. This embodiment is different from the above-described embodiment in that a buffer mechanism 6A using a coil spring 64 is provided between the lower surface of the flange portion 33 and the upper surface of the driving member 53. In this configuration, the support portion of the mounting table 3 serves as the driving member 53, and the coil spring 64 is provided so that the mounting table 3 can swing with respect to the driving member 53. Other configurations are the same as those described above, and the description thereof is omitted.

  FIG. 15 shows a state in which the mounting table 3 is at the transfer position of the wafer W when the inside of the processing container 2 is in an air atmosphere. In this state, the coil spring 64 is in a contracted state, and the height position of the flange portion 33 is set by the positioning mechanism 65. Then, when the inside of the processing container 2 is evacuated, the mounting table 3 receives atmospheric pressure and is drawn to the processing container 2 side, and rises to a position indicated by a dotted line in FIG. As a result, the flange portion 33 is also lifted, so that the coil spring 64 is pulled and extended by the flange portion 33. In this state, as shown in FIG. 16, the mounting table 3 is protruded from the processing position, that is, the surface of the mounting table 3 It is moved to a position where it abuts against the portion 43.

  After the mounting table 3 is moved to the processing position in this way, the drive member 53 is slightly raised, for example, 1 mm as shown in FIG. At this time, since the height position of the mounting table 3 is regulated by the protrusion 43, the coil spring 64 contracts, and the mounting table 3 comes into contact with the protrusion 43 compared to the case where the coil spring 64 is not provided. Contact pressure is relieved. When the drive member 53 is further raised, the amount of contraction of the coil spring 64 increases, and the force for pressing the mounting table 3 against the protrusion 43 increases. For this reason, the rising amount of the drive member 53 is determined in consideration of the expected amount of inclination of the mounting table 3 and the load resistance.

  In the above, the protrusion of the present invention may be provided in at least one of the outer region of the mounting table and the top plate member. For example, as shown in FIG. The protrusions 43A may be provided so as to be separated from each other along the direction, or may be provided on both the mounting table and the top plate member. Moreover, you may make it form a projection part by protruding a part of top plate member or mounting base.

  Furthermore, the shape of the processing container and the top plate member in the film forming apparatus of the present invention is not limited to the above-described configuration. For example, in the configuration shown in FIG. 19, the recess 41 </ b> A of the top plate member 4 </ b> A is configured to have a linear inclined surface, and the exhaust path 82 is connected to the bottom of the processing container 81. In such a film forming apparatus 1A, when the processing container 81 is evacuated by the vacuum pump 83, the atmosphere in the processing space S constituted by the mounting table 3A and the top plate member 4A is formed in the circumferential direction of the mounting table 3. The air is exhausted from the processing space S to the processing container 81 through the gap 40 </ b> A, and further exhausted to the outside of the processing container 81. In FIG. 19, reference numeral 431 denotes a protrusion.

  In the present invention, the processing space S may be configured by the top plate member and the mounting table. For example, as shown in FIG. 20, the lower surface of the top plate member 4B (the surface facing the mounting table) is configured as a flat surface. And you may make it provide the recessed part 38 for forming the process space S in the surface of the mounting base 3B. The step portion 38a of the mounting table 3B corresponds to an outer region, and a gap 40B is formed between this surface and the lower surface of the top plate member 4B. 43B is a protrusion provided on the surface of the stepped portion 38a of the mounting table 3B or the lower surface of the top plate member 4B.

  In the above, the gap formed between the mounting table and the top plate member may be formed between the outer region of the mounting region of the mounting unit and the top plate member facing this outer region, For example, as shown in FIG. 21, a stepped portion 84 that is one step lower is formed in the outer region of the mounting table 3C, and a gap 40C of less than 1 mm is formed between the stepped portion 84 and the top plate member 4C that faces in the vertical direction. The formation is also included in the scope of the present invention. Moreover, as shown in FIG. 22, the case where a gap 40D of less than 1 mm is formed between the side surface of the mounting table 3D and the top plate member 4D facing the mounting table 3D is also included in the scope of the present invention. In the configuration of FIG. 22, a protrusion 43 </ b> D for forming the gap 40 </ b> D is provided between the step portion 84 of the mounting table 3 </ b> D and the top plate member 4 </ b> D facing the step portion 84.

  Further, in the present invention, as shown in FIG. 22, a region for forming an exhaust gap having a distance of less than 1 mm is provided between the outer region of the mounting table and the top plate member facing the outer region. Thus, the gas can be contained in the processing space S. For this reason, the case where the gap is increased to 1 mm or more outside the gap formation region is also included in the scope of the present invention. 19 to 22, the outside of the processing container 81 is not shown.

  Furthermore, the buffer mechanism according to the present invention includes a mounting table or a top plate between at least one of the mounting table and a support portion that supports the mounting table, and between the top plate member and the support portion that supports the top plate member. The member may be provided so as to be able to swing with respect to the support portion, and may be configured to relieve the contact pressure when the projection on one side of the mounting table and the top plate member contacts the other side. In addition to the disc spring, a coil spring, a leaf spring, or the like can be used as the elastic member incorporated in the buffer mechanism.

  For example, as shown in FIGS. 23 and 24, when the mounting table is moved up and down, a buffer mechanism may be provided between the top plate member and a support portion that supports the top plate member. In this example, a buffer mechanism 92, for example, a disc spring, is provided between the top surface of the top plate member 91 and the ceiling portion 90 of the processing container 9, so that the top plate member 91 swings on the ceiling portion 90 that is a support site. It is provided so that it can move. In FIG. 23, the inside of the processing container 9 is evacuated by the vacuum pump 93, the mounting table 94 comes into contact with the protrusion 95 provided on the lower surface of the top plate member 91, and the mounting table 94 and the top plate member 91 are A state in which the processing space S is formed therebetween (a state in which the mounting table 94 is at the processing position) is shown. In the figure, 96 is a flange portion, 96a is a bellows body, 97 is an elevating mechanism, 97a is configured to be movable up and down by the elevating mechanism, a driving member connected to the bellows body 96a, and 98 is a gas supply unit.

  Then, when the drive member 97a is raised by a predetermined distance from this state, as shown in FIG. 24, the mounting table 94 presses the buffer mechanism 92 from the lower side via the projection 95 and the top plate member 91, and the buffer mechanism 92 Shrink. Thereby, the contact pressure when the mounting table 94 comes into contact with the protruding portion 95 is relieved.

(Second Embodiment)
Then, the film-forming apparatus of the 2nd Embodiment of this invention is demonstrated, referring FIGS. 25-27. The second embodiment corresponds to the first independent claim (Claim 1), and the film forming apparatus of this example is for exhausting between the mounting table 3 and the top plate member 4. The size of the gap is adjustable. In addition, about the structure similar to 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  In the following, the description will be focused on differences from the film forming apparatus of the first embodiment. The lower end side of the support member 32 in this example is connected to the flange portion 33 via the intermediate flange portion 301. The lower surface of the intermediate flange portion 301 is fixed to the upper surface of the flange portion 33 by a plurality of rod members 302 extending in the vertical direction, and a bellows body 34 is provided between the intermediate flange portion 301 and the processing container 2. ing.

  Similar to the first embodiment described above, the upper surface of the flange portion 33 has a first buffering mechanism 6 on one end side in the left and right direction (X direction in FIG. 25) outward from the rod member 302. The drive member 53 of the lifting mechanism 5A is connected to the other end side in the left-right direction outside the rod member 302, and the driving member 53 of the second lifting mechanism 5B is connected via the buffer mechanism 6. ing. The configurations of the buffer mechanism 6 and the lifting mechanism 5 (first and second lifting mechanisms 5A and 5B) are the same as those in the first embodiment, and the drive member 53 corresponds to the support portion.

  Here, the height position of the mounting table 3 shown in FIG. 25 is a delivery position of the wafer W when the inside of the processing container 2 is in an air atmosphere. In this state, as described above, the weight of the mounting table 3 is applied to the flange portion 33, and the flange portion 33 is fitted with the protrusion 55 a of the positioning mechanism 55 so that the height position of the flange portion 33 is set. It has been decided.

  In the figure, reference numeral 110 denotes a regulating mechanism. When the mounting table 3 and the top plate member 4 are separated from each other, the restricting mechanism 110 maintains the corrected relative position so that the relative posture of the mounting table 3 with respect to the top plate member 4 is corrected. This suppresses the action of the target posture to return to the original position. The restriction mechanism 110 includes, for example, a push screw 111 that forms a lifting shaft provided so as to pass through the flange portion 33 from below and rise toward the drive member 53, and a tip of the push screw 111 is connected to the drive member 53. A nut 112 is provided as a fixing member that fixes the height position of the lower surface when it comes into contact with the lower surface. The lower end side of the push screw 111 is connected to a rotation mechanism 113 made of, for example, a motor.

  As shown in FIG. 26, the outer surface of the push screw 111 is threaded, and a screw hole 330 corresponding to the push screw 111 is formed in the flange portion 33, and the inner surface of the screw hole 330 has the push screw 111. A threaded portion 331 that is screwed into the thread is formed. The nut 112 is provided, for example, on the lower side of the flange portion 33, and a screw portion 114 that is screwed into the threading of the push screw 111 is formed on the inner surface thereof. By tightening the nut 112, the push screw 111 is formed. The height position of is fixed.

  The flange portion 33 is configured to have a circular planar shape, and the driving member 53 is configured to have, for example, a ring shape as illustrated in FIG. A plurality of, for example, four push screws 111 are provided, one on each of the back side and the near side in the depth direction (Y direction in FIG. 27) with respect to the ball screws 51 of the elevating mechanisms 5A and 5B. . Further, in this embodiment, no projection is formed between the top plate member 4 and the mounting portion 3, and the flat portion 42, which is the peripheral region of the top plate member 4, and the mounting table 3 are mounted. The outer region of the placement region 30 is configured to abut against each other and form a processing space therebetween.

  Subsequently, the operation of the film forming apparatus 1 according to the second embodiment will be described with reference to FIGS. 28 to 32. First, the operation at the time of adjustment before loading the wafer W will be described. This adjustment is performed, for example, when the mounting table 3 is adjusted to be relatively horizontal with respect to the top plate member 4 or the exhaust gap 40 formed between the mounting table 3 and the top plate member 4. This is done when the size is changed.

  First, in the processing container 2 in an atmospheric atmosphere (atmosphere before the processing container 2 is evacuated), the mounting table 3 is positioned at the delivery position and evacuated by the vacuum pump 27 (step S11). By setting the inside of the processing container 2 to a vacuum atmosphere, the flange portion 33 receives atmospheric pressure and is drawn to the processing container 2 side, and the mounting table 3 is slightly raised from the position of the atmospheric atmosphere. As the flange portion 33 is raised, the protrusion 33 a on the upper surface of the flange portion 33 is fitted into the recess 53 b on the lower surface of the drive member 53. At this time, the buffer mechanism 6 is loaded and contracted.

  Next, as shown in FIG. 29, the first and second lifting mechanisms 5 </ b> A and 5 </ b> B raise the mounting table 3 to a position where the peripheral area of the mounting table 3 abuts against the flat surface portion 42 of the top plate member 4 (step). S12). At this time, by setting the inside of the processing container 2 to a vacuum atmosphere, the flange portion 33 receives atmospheric pressure and is attracted to the processing container 2 side. The mounting table 3 is raised through the flange portion 33, the rod member 302, the intermediate flange portion 301, and the support member 32. For this reason, the motors 54 of the first and second elevating mechanisms 5A and 5B are synchronized with each other, and are raised in a state where the rising amounts are uniform.

  Thus, after the mounting table 3 is brought into contact with the top plate member 4, as shown in FIG. 30, the driving member 53 is slightly raised, for example, by 1 mm (step S13). As a result, a force acts on the mounting table 3 in a direction approaching the top plate member 4, but the height of the mounting table 3 is regulated by the top plate member 4, and therefore, as shown in FIG. Thus, the disc spring 61 of the buffer mechanism 6 extends. Thus, the buffer mechanism 6 is surely pressed so that the entire peripheral area of the mounting table 3 is in close contact with the top plate member 4 while relaxing the contact pressure when the mounting table 3 contacts the top plate member 4. The posture of the mounting table 3 is corrected so that the mounting table 3 is relatively parallel to the top plate member 4. At this time, for example, when the mounting table 3 is made of ceramics such as aluminum nitride, the load resistance is 600 N to 800 N or less, so the driving member 53 is brought into contact with the top plate member 4 after the mounting table 3 is brought into contact with the top plate member 4. For example, the distance for increasing the distance is set to about 2 to 3 mm so that the combined load becomes smaller than the load resistance.

  In this state, as shown in FIG. 31, the push screw 111 is lifted by the rotation mechanism 113 to be tightened with a constant torque, and the tip of the push screw 111 is brought into contact with the drive member 53. Next, the nut 112 is tightened to fix the height position of the push screw 111, and the pulse value of the encoder of the motor 54 of the elevating mechanisms 5A and 5B at this time is stored in the control unit 100 as a reference position ( Step S14). In this way, the relative posture between the drive member 53 and the flange portion 33 is regulated by the push screw 111 in a state where the upper surface of the outer region of the mounting table 3 is relatively parallel to the lower surface of the peripheral region of the top plate member 4. Is done. For this reason, even when the mounting table 3 and the top plate member 4 are separated from each other, the relative posture between the driving member 53 and the flange portion 33 does not change, and the relative posture of the mounting table 3 with respect to the top plate member 4 is not changed. The corrected state is maintained. That is, even when the mounting table 3 and the top plate member 4 are separated from each other, since the relative posture between the drive member 53 and the flange portion 33 is regulated by the push screw 111, the extended flat head screw 61 is Shrinkage due to a pressure difference between the inside and outside of the processing container 2 in a vacuum atmosphere (atmospheric pressure atmosphere) is suppressed, and thus the action of the relative posture after correction is restored.

  If the restriction mechanism 110 is not provided, the driving member 53 is lowered by the elevating mechanisms 5A and 5B so that the mounting table 3 and the top plate member 4 are separated from each other. When the action of pressing on the member 4 is released, the relative posture after correction tends to return to the original due to the pressure difference between the inside and the outside (atmospheric pressure atmosphere) of the processing container 2 in the vacuum atmosphere as described above. An effect | action generate | occur | produces and the some countersunk screw 61 will shrink | contract uniformly. For this reason, the state where the relative posture of the mounting table 3 with respect to the top plate member 4 cannot be maintained.

  Therefore, the driving member 53, the countersunk screw 61 of the buffer mechanism 6, and the set screw 111 of the regulating mechanism 110 are fixed to the top plate member 61 by the countersunk screw 61 when one side of the mounting table 3 and the top plate member 4 is biased to the other side. 4 can correct the relative posture of the mounting table 3, and when the mounting table 3 and the top plate member 4 are separated from each other, the push screw 111 comes into contact with the lower surface of the drive member 53 and the mounting table with respect to the top plate member 4. The installation location, shape, and size are set so that the relative posture of 3 is maintained.

  Next, with the regulation mechanism 110 maintaining the correction of the relative posture of the mounting table 3 with respect to the top plate member 4, the mounting table 3 is lowered by the lifting mechanisms 5A and 5B. Thus, as shown in FIG. 32, the exhaust gap 40 having a predetermined size is formed between the mounting table 3 and the top plate member 4, and the pulse value of the encoder of the motor 54 at this time is controlled as the processing position. Stored in the unit 100 (step S15). As a result, a narrow gap 40 having a uniform width (distance between the mounting table 3 and the top plate member 4) in the circumferential direction of the mounting table 3 is removed from the periphery of the wafer W or the outer region of the wafer W. Can be formed in the direction. The narrow gap 40 is set such that the distance between the mounting table 3 and the top plate member 4 is, for example, 0.1 mm or more and 1.5 mm or less. Thus, the adjustment work is completed.

  Here, the case where the mounting table 3 is lifted in a biased state will be described with reference to FIG. When the mounting table 3 rises in a tilted state, when the mounting table 3 moves to a position where it comes into contact with the top plate member 4, as shown in FIG. Although it is in contact, it is not in contact with other parts. In this state, when the drive member 53 is slightly raised, a part of the buffer mechanism 6 is extended, whereby the mounting table 3 can swing with respect to the drive member 53 and is not in contact with the top plate member 4. The area rises as the drive member 53 rises while the mounting table 3 swings and the inclination is adjusted. For this reason, as shown in FIG. 33B, the top plate member 4 extends in the circumferential direction in the outer region of the mounting table 3 while preventing an excessive force from being applied between the mounting table 3 and the flat surface portion 42. Can be pressed firmly against. Therefore, if the height position of the drive member 53 is fixed by the push screw 111 of the restriction mechanism 110 in this state, the mounting table 3 with respect to the top plate member 4 even when the mounting table 3 and the top plate member 4 are separated from each other. The state in which the relative posture is corrected is maintained.

  As a result, as shown in FIG. 33 (c), if the driving member 53 is lowered while maintaining the state where the relative posture of the mounting table 3 with respect to the top plate member 4 is corrected by the restriction mechanism 110, the mounting table The exhaust gap 40 having a uniform width in the circumferential direction can be formed between the top plate member 4 and the top plate member 4 with high accuracy.

  On the other hand, a case where the restriction mechanism 110 is not provided will be described with reference to FIG. After the mounting table 3 is lifted in an inclined state and a part of the mounting table 3 is brought into contact with the top plate member 4 (FIG. 34 (a)), the driving member 53 is slightly lifted, whereby the mounting table 3 Up to the step of reliably pressing the top plate member 4 (FIG. 34B) is as described in FIG. However, after that, when the drive mechanism 53 is lowered to form the gap 40, the relative posture between the drive mechanism 53 and the flange portion 33 is not restricted. Thus, the state in which the relative posture of the mounting table 3 with respect to the top plate member 4 is not maintained can be maintained, and as a result, the mounting table 3 returns to a biased state. For this reason, a gap 40 having a uniform width in the circumferential direction cannot be formed between the mounting table 3 and the top plate member 4.

  Next, the operation during the film forming process of the wafer W will be described. First, in a state where the inside of the processing container 2 is maintained in a vacuum atmosphere, the mounting table 3 is positioned at the delivery position, the transfer port 28 is opened, the wafer W is loaded into the processing container 2, and is received on the mounting table 3. (Step S21) Next, after the transfer port 28 is closed, the mounting table 3 is raised to the processing position by the first and second lifting mechanisms 5 </ b> A and 5 </ b> B, and an exhaust gap is provided between the mounting table 3 and the top plate member 4. The processing space S is formed while forming 40 (step S22).

  Thus, the inside of the processing container 2 is evacuated to, for example, 13.3 Pa (0.1 Torr), and when the temperature is raised to 350 ° C. to 650 ° C. that is the film forming temperature of the wafer W by the heater 31, the film forming process is started. A process is executed as in the first embodiment (step S23). When the film forming process is completed, the gas supply is stopped, and the mounting table 3 on which the wafer W is mounted is lowered to the delivery position while the inside of the processing container 2 is maintained in a vacuum atmosphere (step S24). Then, the wafer W is unloaded by an external transfer mechanism through a path opposite to that at the time of loading, and a series of film forming operations is completed (step S25). When there is a wafer W to be processed next, the operations in steps S21 to S25 are repeated.

  At this time, after the inside of the processing container 2 is returned to the air atmosphere, when the vacuum processing is performed on the wafer W of the next lot, if the size of the gap 40 to be formed is the same, The film forming process of the wafer W may be performed without performing the above operation, or the operation at the time of the adjustment may be performed again. Further, when the inside of the processing container 2 is returned to the air atmosphere and the vacuum processing is performed on the wafer W of the next lot, and the size of the gap 40 is changed, the operation at the time of the adjustment is performed. The mounting table 3 may be set to a predetermined height based on the acquired reference position of the motor 54 described above without performing the adjustment operation.

  According to the embodiment described above, the mounting table 3 is moved up and down relatively with respect to the top plate member 4 while the regulation mechanism 110 maintains the correction of the relative posture of the top plate member 4 with respect to the mounting table 3. Thus, an exhaust gap 40 is formed in the circumferential direction of the wafer W. For this reason, a narrow gap 40 having a uniform width in the circumferential direction of the wafer W can be formed with high accuracy. Accordingly, since the gap 40 can be formed uniformly in the circumferential direction of the mounting table 3, the exhaust amount is aligned in the circumferential direction of the mounting table 3 in the processing space S. As a result, a process with good in-plane uniformity can be performed, and a thin film with uniform film characteristics such as film thickness, film quality, and specific resistance can be obtained over the wafer W plane.

  Furthermore, the gap 40 can be freely set to a predetermined size while making the exhaust gap 40 uniform in the circumferential direction of the wafer W. Therefore, the size of the gap 40 can be freely set without changing the apparatus configuration, and the size of the gap 40 can be controlled as a parameter of the film formation process. The 40 size can be optimized. At this time, when the combination of the push screw 111 and the nut 112 is used as the restriction mechanism 110, the configuration is simple, and the fixing operation of the relative posture between the top plate member 4 and the mounting table 3 can be easily performed. In addition, it can be easily incorporated into a conventional film forming apparatus. Moreover, since the mounting table 3 and the top plate member 4 do not come into contact with each other during the film forming process, it is possible to eliminate the concern about the generation of particles.

  Furthermore, since the buffer mechanism 6 is provided, even when the mounting table 3 is biased and comes into contact with the top plate member 4, the relative posture of the mounting unit 3 with respect to the top plate member 4 is corrected and the mounting table 3 is mounted. The entire peripheral area of the mounting table 3 can be reliably pressed against the top plate member 4 while relaxing the contact pressure when the mounting table 3 contacts the top plate member 4.

  As described above, this embodiment can also be applied to the film formation apparatus illustrated in FIGS. The film forming apparatus shown in FIG. 35 has a configuration in which the protrusion 43 is not provided in the film forming apparatus shown in FIG. 15, and the outer region of the mounting table 3 is brought into contact with the flat part 42 of the top plate member 4. The drive member 53 is raised by a predetermined amount, for example, 1 mm, and the mounting table 3 is reliably pressed against the top plate member 4 by the buffer mechanism 6A using the coil spring 64. At this time, the coil spring 64 is in a contracted state. When adjusting the gap 40, the push screw 111 is raised, the tip of the push screw 111 is brought into contact with the drive member 53, the nut 112 is tightened, and the height of the push screw 111 is increased. Fix the position. Thereby, when the mounting table 3 and the top plate member 4 are separated from each other, the corrected relative posture is maintained so that the relative posture of the mounting table 3 with respect to the top plate member 4 is maintained. The action to return to the original is suppressed. Here, the action of returning the relative posture after correction to the original occurs due to a restoring action of the coil spring 64 to extend. Next, the mounting table 3 is lowered by the lifting mechanisms 5A and 5B to form an exhaust gap 40 of a predetermined size between the mounting table 3 and the top plate member 4. At this time, the lifting mechanisms 5A and 5B The control unit 100 stores the encoder pulse value of the motor 54 as a processing position.

  Further, the film forming apparatus shown in FIG. 36 has a configuration in which the protrusion 95 is not provided in the film forming apparatus shown in FIG. 23, and the outer region of the mounting table 3 is brought into contact with the flat part of the top plate member 91. The state where the flange portion 96 is raised by a predetermined amount, for example, 1 mm is shown, and the mounting table 94 is reliably pressed against the top plate member 91 by the buffer mechanism 92. At this time, the disc spring of the buffer mechanism 92 is in a contracted state. The top plate member 91 of this example includes a horizontal flange portion 91 a on the outer wall, and a regulating mechanism 120 including a lifting shaft 122 configured to be lifted and lowered by a motor 121 below the flange portion 91 a. Is provided. In the figure, 121 a is a bellows, and the motor 121 is arranged outside the processing container 9. When adjusting the clearance, as described above, the flange portion 96 is raised by, for example, 1 mm, and the lifting shaft 122 is raised while the mounting table 94 is securely pressed against the top plate member 91. Then, the tip of the lifting shaft 122 is brought into contact with the lower surface of the flange portion 91a, and the height position of the lifting shaft 122 is fixed at that position. In this example, the motor 121 corresponds to a fixing member that fixes the height position of the lifting shaft 122. Thereby, when the mounting table 94 and the top plate member 91 are separated from each other, the corrected relative posture is maintained so that the relative posture of the mounting table 94 with respect to the top plate member 91 is maintained. The action to return to the original is suppressed. Here, the action in which the relative posture after correction is to return to the original occurs due to a restoring action in which the disc spring attempts to extend.

  In this way, while the regulation mechanism 120 maintains the correction of the relative posture of the mounting table 94 with respect to the top plate member 91, the mounting table 94 is lowered by the elevating mechanism 97, whereby the mounting table 94 and the top plate member 91 are moved. In the meantime, an exhaust gap having a uniform width is formed so as to surround the wafer W. At this time, the elevating mechanism 97 is composed of a motor, and the pulse value of the encoder of this motor is stored in the control unit 100 as a processing position. .

  Further, in the film forming apparatus shown in FIG. 37, the buffer mechanism 6 using the disc spring 61 is provided between the lower surface of the intermediate flange portion 301 and the upper surface of the drive member 53, and the regulating mechanism 110 includes the push screw 111. Is provided so as to penetrate the flange portion 33 from below. Further, for example, instead of the vacuum pump 27, an exhaust means 130 for exhausting the inside of the processing container 2 is provided, and the rest is configured similarly to the film forming apparatus shown in FIG.

The operation of this film forming apparatus will be described by taking as an example a case where the inside of the processing container 2 is set to an air atmosphere to perform the film forming process. As an example of such a film forming process, a first reaction gas such as HfCl ₄ and a second reaction gas such as H that reacts with the first reaction gas to form a reaction product in an air atmosphere. A process of supplying ₂ O and forming an HfO ₂ film by ALD can be given.

  When adjusting the gap 40, first, the driving member 53 is raised by the elevating mechanisms 5A and 5B to raise the mounting table 3 via the buffer mechanism 6 and the intermediate flange portion 301. The mounting table 3 is brought into contact with the top plate member 4. At this time, when the drive member 53 is raised, the drive member 53 approaches the intermediate flange portion 301, so that the disc spring 61 is contracted, but at this time, the disc spring 61 is formed so as not to contract completely. Keep it. Next, by slightly raising the elevating mechanisms 5A and 5B, the placing table 3 is reliably pressed against the top plate member 4 even when the placing table 3 is lifted in an inclined state by the action of the buffer mechanism 6. At this time, the disc spring 61 of the buffer mechanism 6 is in a further contracted state.

  Next, the push screw 111 is raised to a predetermined torque, the tip of the push screw 111 is brought into contact with the lower surface of the drive member 53, and then the nut 112 is tightened to fix the height position of the push screw 111. To do. Thereby, when the mounting table 3 and the top plate member 4 are separated from each other, the corrected relative posture is maintained so that the relative posture of the mounting table 3 with respect to the top plate member 4 is maintained. The action to return to the original is suppressed. Here, the action of returning the relative posture to the original occurs due to a restoring action of the disc spring 61 trying to extend. Next, the mounting table 3 is lowered by the lifting mechanisms 5A and 5B to form an exhaust gap 40 of a predetermined size between the mounting table 3 and the top plate member 4. At this time, the lifting mechanisms 5A and 5B The control unit 100 stores the encoder pulse value of the motor 54 as a processing position. At this time, in the film forming apparatus shown in FIG. 37, the processing container 2 may be evacuated by the vacuum pump 27 and the film forming process may be performed in a vacuum atmosphere, or the film forming process may be performed in a low pressure atmosphere. It may be. For example, when the film forming process is performed in a vacuum atmosphere, the intermediate flange portion 301 is drawn toward the processing container 2 due to the pressure difference between the inside and the outside of the processing container 2 by evacuating the inside of the processing container 2. Therefore, the buffer mechanism 6 is formed in consideration of that amount. Alternatively, the mounting table 3 may be made heavy or the repulsive force of the bellows body 34 may be increased so that the intermediate flange portion 301 moves to the opposite side of the processing container 2 even when the inside of the processing container 2 is in a vacuum state.

  In the above, the second embodiment has been described by taking as an example the case where no protrusion is provided, but the present embodiment can also be applied to a configuration in which a protrusion is provided. In this case, the gap regulated by the protrusion becomes the minimum value, and a gap larger than this value can be set freely. Also, the film forming apparatus shown in FIGS. 19 to 22 described above may be provided with the restriction mechanism of the second embodiment so that the size of the exhaust gap can be adjusted. In the above example, the push screw 111 is raised by the rotation mechanism 113. However, an operator may raise the push screw 111 using a torque wrench or the like and fix it by the nut 112. Further, the nut 112 may be automatically engaged using a nut rotation mechanism.

  Furthermore, in the second embodiment, in the configuration in which the top plate member is moved up and down by the lifting mechanism, the top plate member and the top plate member are supported between the mounting table and the support portion that supports the mounting portion. A buffer mechanism is provided in at least one of the supporting parts, and when the mounting table and the top plate member are separated from each other, the relative posture of the mounting table with respect to the top plate member is maintained in a corrected state. A regulating mechanism may be provided for regulating the action of the relative posture after correction to return to the original position. At this time, the action of returning the relative posture after correction to the original may be an action generated by a restoring action of the buffer mechanism or an action generated by a pressure difference between the inside and the outside of the processing container. It may be. Further, it may be an action generated by both the restoring action of the buffer mechanism and the action generated by the pressure difference between the inside and the outside of the processing container. Further, the film forming apparatus shown in FIGS. 25 and 33 may be combined with a regulating mechanism using a fixing member composed of a lifting shaft and a motor. Furthermore, the configuration is not limited to the above as long as the height position is regulated by the fixing member when the tip of the elevating shaft, for example, the push screw comes into contact with the flange portion or the drive member.

  In the above, as an example of correcting the relative posture of the mounting table 3 with respect to the top plate member 4, the gap is made uniform in the circumferential direction so that both the top plate member 4 and the mounting table 3 are parallel to each other. Although the structure to perform was described, you may comprise so that the clearance gap may become non-uniform | heterogenous in the circumferential direction and the exhaust capability of a specific direction may be improved by changing the amount which the push screw 111 tightens.

(Third embodiment)
Next, a film forming apparatus according to a third embodiment of the present invention will be described with reference to FIGS. The film forming apparatus of this embodiment detects a pressure in the processing container 2 and detects an abnormality in the gap between the mounting table 3 and the top plate member 4. Hereinafter, the description will be given by taking as an example the case where the present embodiment is applied to the film forming apparatus of the second embodiment. The same reference numerals are given to the same configurations as those of the second embodiment, and the description will be continued. Is omitted.

In FIG. 38, reference numeral 200 denotes a pressure sensor that forms a detection unit. The pressure sensor 200 detects a pressure in the processing container 2, and does not adversely affect film formation of the wafer W in the processing container 2, for example. The top plate member 4 is provided on the surface facing the mounting table 3. Further, the gas supply unit 7 includes a first gas supply path 71 for the first reaction gas, a second gas supply path 72 for the second reaction gas, and a third gas supply path for the purge gas. In addition to 73, a fourth supply path 74 for cleaning gas is connected. The fourth supply path 74 is connected to a cleaning gas supply source 74b via a flow rate adjustment unit 74a having a flow rate adjustment valve, an open / close valve, and the like. In the case of forming a titanium nitride film (TiN film), for example, a ClF ₃ gas is used as the cleaning gas. In this example, the gas supply unit 7, the fourth supply path 74, the flow rate adjustment unit 74 a, and the supply source 74 b correspond to a cleaning gas supply unit that supplies a cleaning gas for removing a film attached in the processing space. .

  Further, the pressure sensor 200 is configured so that, for example, the detection value is output to the monitor 201 forming the display unit at a predetermined interval, for example, an interval of 0.1 seconds, and is output to the control unit 100. The control unit 100 includes a program for executing a gap evaluation process in addition to the above-described film formation process. This evaluation process program has, for example, a function for determining whether or not a detection value is within a preset pressure setting range at a predetermined timing, and a function for outputting a control signal so as to introduce a purge gas at a predetermined timing. And a function of outputting a control signal to execute the film forming process when the detected value is determined to be within the set range, and a cleaning gas supply unit to introduce a cleaning gas when determined to be out of the set range. A function of outputting a control signal to the flow rate adjusting unit 74a and a function of outputting an alarm signal are configured to be executed.

  Next, the operation of this embodiment including the gap abnormality evaluation process will be described with reference to the flowchart of FIG. First, the wafer W is loaded into the processing container 2, the mounting table 3 is raised to the processing position, and the above-described film forming process is executed (step S31). The processing position is a position where an exhaust gap 40 having a predetermined size is formed between the mounting table 3 and the top plate member 4. The adjustment of the gap 40 and the film formation process are performed by the first process described above. This is as shown in the embodiment and the second embodiment. In this way, the film forming program is executed on a plurality of, for example, 100 wafers W, and after the final wafer W is unloaded, the evaluation process is executed. In this evaluation process, first, a first purge gas introduction step is performed (step S32). In this step, with the wafer W not being placed, the mounting table 3 is raised to the processing position to form the processing space S, and a purge gas having a predetermined flow rate, for example, 3600 sccm is introduced into the processing space S for 15 seconds, for example. After completing the introduction of the purge gas, it is determined at a predetermined timing whether or not the detection value of the pressure sensor 200 is within the set range (step S33).

  If the film forming process is continued, the film 203 may adhere to the exhaust gap 40 as shown in FIG. When a film is formed in the gap 40 in this way, the gap 40 is as narrow as 1 mm or less, for example, so that gas is hardly exhausted from the processing space S, and the pressure in the processing space S increases. Therefore, when the detection value of the pressure sensor 200 is within the set range, it is determined that the film 203 is not formed in the gap 40, that is, the gap 40 is in a normal state. In this case, a control signal for continuing the film forming process is output (step S37), and the film forming process is performed on the wafer W based on the control signal.

  On the other hand, when the detection value of the pressure sensor 200 is out of the set range, it is determined that some abnormality has occurred in the gap 40. Therefore, a control signal is output so that a cleaning process for removing the film adhering to the gap 40 is performed (step S34). In this step, a cleaning gas having a predetermined flow rate, for example, 120 sccm, is introduced into the processing space S for 3600 seconds, for example, and the film 203 attached to the gap 40 is removed.

  Next, after the introduction of the cleaning gas is stopped, a second purge gas introduction step is performed (step S35). In this step, a purge gas having a predetermined flow rate, for example, 3600 sccm is introduced into the processing space S for 15 seconds, for example. After completing the introduction of the purge gas, at a predetermined timing, the control unit 100 determines whether or not the detected value of the pressure sensor 200 is within the set range (step S36).

  When the detection value of the pressure sensor 200 is within the set range, it is determined that the film 203 has been removed from the gap 40 and returned to a normal state, and a control signal is output to continue the film formation process (step) S37) Based on this, a film forming process is performed on the wafer W. On the other hand, when the detected value is out of the set range, it is determined that the gap 40 is still in an abnormal state, and an alarm signal is output (step S38). The abnormality of the gap 40 in this case may be caused by a mechanical change in the size of the gap 40, for example, as shown in FIG. 40 (b), in which the mounting table 3 is in contact with the top plate member 4 in an inclined state. It also includes the case of doing. In this alarm output step, alarms such as generation of warning sounds, lighting of alarm lamps, and alarm display on the monitor 201 screen are output. When this alarm is output, the operator investigates the cause of the abnormality in the gap and performs the work for eliminating the cause.

  According to the above-described embodiment, the exhaust gap 40 formed between the mounting table 3 and the top plate member 4 is narrow, so that a film adheres to the gap 40 or the gap 40 is mechanically. When there is an abnormality such as a change in the size of the pressure, the pressure in the processing space S changes. Therefore, by detecting the pressure in the processing space S, displaying the detected values on the monitor 201 at predetermined intervals, and monitoring the pressure in the processing space S 2, it is determined whether or not there is an abnormality in the gap 40. Can be evaluated. At this time, by monitoring the pressure change, it is possible to respond immediately when there is an abnormality, so that it is possible to suppress the continuous execution of the film forming process in a state where a defect has occurred. As a result, a state in which the narrow gap 40 is formed with a uniform width in the circumferential direction of the wafer W is ensured, so that the film forming process can be carried out in a stable state, a decrease in yield can be suppressed, and throughput can be suppressed. Can be suppressed.

  If the abnormality of the gap 40 is caused by the adhesion of the film, the cause of the abnormality can be quickly eliminated by performing cleaning. Also in this case, by monitoring the pressure change, it is possible to immediately cope with an abnormality, so that film deposition is suppressed and the film in the gap 40 is easily removed by cleaning. Further, by determining again whether or not the pressure in the processing space S is within the set range after cleaning, it is possible to quickly cope with the case where the abnormality of the gap 40 is caused by a mechanical cause. Can do.

  In the above, the third embodiment may be applied to the apparatus of the first embodiment described above, and the detected pressure value is within the set range every time one wafer W is processed. It may be determined whether or not. Further, when the detected pressure value is out of the set range, an alarm signal may be output immediately without performing the cleaning process. Further, the operator monitors the pressure value with the monitor 201, determines that there is an abnormality when the pressure value is out of the set range, and performs a predetermined response such as execution of cleaning or execution of mechanical inspection. It may be.

In the above, the pressure sensor 200 may be provided inside the gas supply path 70. Further, for example, by providing a pressure increase in the processing container 2 due to gas leaking from the processing space S provided outside the processing space S such as around the exhaust part 24, the top plate member 4 and the mounting table 3 It may be determined whether or not the gap between them is in a normal state.

  In the present invention, the width between the mounting portion and the top plate member is constant in each step of the adsorption process, the purge process, and the reduction process, but the operation of the film forming apparatus according to the present embodiment is It is not limited to examples. For example, by changing the width of the gap in the adsorption process and the reduction process, and changing the pressure in the processing space according to the type of reaction gas supplied in each process, a high-quality film is formed. May be.

  In the above-described configuration, the case where two ball screw mechanisms are used as the lifting mechanism has been described. However, one or three or more lifting mechanisms may be used. Furthermore, the present invention is not limited to the method of raising and lowering the mounting table, and the top plate member can be raised and lowered, the top plate member is raised and lowered, and a buffer mechanism is provided between the top plate member and the support portion. You may make it provide. Further, both the mounting table and the top plate member may be moved up and down. In this case, a buffer mechanism may be provided between the mounting table and the top plate member and the respective support portions, or the mounting table and the top plate member may be provided. A buffer mechanism may be provided between any one of the plate members and the support portion. Furthermore, the structure which provides a buffer mechanism between the raising / lowering mechanism which raises / lowers a mounting part and a top-plate member, and the support part which supports this raising / lowering mechanism is also contained in the scope of the present invention.

  Further, in the present invention, when the mounting table is positioned at the processing position, the inside of the processing container only needs to be set to a vacuum atmosphere, and after the mounting table is raised to a predetermined position below the top plate member in the air atmosphere. The inside of the processing container may be set to a vacuum atmosphere. At this time, in consideration of the fact that the mounting table is attracted and raised in a vacuum atmosphere, the mounting table is raised to near the lower side of the processing position in the air atmosphere, and the inside of the processing container is set to a vacuum atmosphere and vacuumed. You may make it move a mounting base to a processing position by drawing a mounting base.

Furthermore, in the film forming apparatus of the present invention, in addition to the above-described TiN film formation, a metal element, for example, an element of the fourth period of the periodic table, such as Al or Si, which is an element of the third period of the periodic table, is used. Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ge, etc. Zr, Mo, Ru, Rh, Pd, Ag, etc., which are the elements of the fifth period of the periodic table, etc. It is possible to form a thin film containing elements such as Ba, Hf, Ta, W, Re, lr, and Pt, and as a metal raw material to be adsorbed on the surface of the wafer W, organic metals of these metal elements are used. The case where a compound, an inorganic metal compound, etc. are used as reaction gas (raw material gas) is mentioned. Specific examples of the metal raw material include, in addition to TiCl ₄ described above, BTBAS ((Bistial Butylamino) silane), DCS (dichlorosilane), HCD (hexadichlorosilane), TMA (trimethylaluminum), 3DMAS (Trisdimethyl). Aminosilane) and the like.

Further, for the reaction to obtain a desired film by reacting the raw material gas adsorbed on the surface of the wafer W, for example, an oxidation reaction using O ₂ , O ₃ , H ₂ O, etc., H ₂ , HCOOH, CH ₃ COOH, etc. Reduction reaction using alcohols such as organic acids, CH ₃ OH, C ₂ H ₅ OH, etc., carbonization reaction using CH ₄ , C ₂ H ₆ , C ₂ H ₄ , C ₂ H _2, etc., NH ₃ Various reactions such as nitriding reaction using NH ₂ NH ₂ , N _2, etc. can be used.

At this time, the present invention is not limited to the case where there are two kinds of reactive gases, and the present film forming apparatus can also be applied to a process for forming a film by ALD using three kinds of reactive gases or four kinds of reactive gases. . For example, as an example of a case of using three kinds of reaction gases may be deposited strontium titanate (SrTiO _3), this time for example, the Sr material Sr _{(THD) 2} (strontium bis tetramethylheptanedionate isocyanatomethyl) Ti (OiPr) ₂ (THD) ₂ (titanium bisisopropoxide bistetramethylheptanedionate) which is a Ti raw material, and ozone gas which is an oxidizing gas thereof are used.

(Example 1)
Using the film forming apparatus shown in FIG. 1, a processing space S is formed between the mounting table 3 and the top plate member 4, N ₂ gas is supplied to the processing space S, and the pressure in the processing space S is measured. did. At this time, the size of the gap 40 between the mounting table 3 and the top plate member 4 was changed, and the flow rate of N ₂ gas was changed to measure the pressure in the processing space S in each case. The result is shown in FIG. In the figure, the horizontal axis indicates the flow rate of N ₂ gas supplied into the processing space S, and the vertical axis in the figure indicates the pressure in the processing space S. In FIG. 41, the case where the gap is 0.3 mm is plotted with ◇, the case where the gap is 1.0 mm, the case where the gap is 10 mm, □, and the pressure in the exhaust section 24 are plotted with ●.

  Thereby, when the gap is 10 mm, the pressure in the processing space S and the pressure of the exhaust section 24 are substantially the same, whereas when the gap is 1.0 mm and 0.3 mm, the supply amount of N2 gas It was recognized that the pressure in the processing space S increased as the amount of increased. As a result, it is understood that when the gap is less than 1.0 mm, the gas can be contained in the processing space S. The smaller the gap, the greater the gas containment effect, and the pressure in the processing space S can be increased. It is understood that the differential pressure between the processing space S and the exhaust part 24 can be increased.

(Example 2)
Using the film formation apparatus shown in FIG. 1, a TiN film is formed using TiCl ₄ gas as the first reaction gas (raw material gas), NH ₃ gas as the second reaction gas (reducing gas), and N ₂ gas as the purge gas. Membrane treatment was performed. At this time, by changing the size of the gap 40 between the mounting table 3 and the top plate member 4, the TiN film is formed by changing the pressure at the time of the reduction process by introducing NH ₃ gas. The specific resistance was measured. The result is shown in FIG. In the figure, the horizontal axis represents the pressure in the processing space S during the reduction process, and the vertical axis represents the specific resistance of the TiN film.

  Thereby, it was recognized that the specific resistance of the TiN film decreases as the pressure in the processing space S during the reduction process increases. Thus, by enclosing the reducing gas in the processing space S and increasing the pressure in the processing space S, the amount of reducing gas supplied to the surface of the wafer W increases, and as a result, the specific resistance of the TiN film decreases. It is understood that the film characteristics can be improved.

W Semiconductor wafer 1 Film forming apparatus 2 Processing container 27 Vacuum pump 3 Mounting table 4 Top plate member 43 Protruding part 5 (5A, 5B) Elevating mechanism 53 Driving member 6 Buffer mechanism 61 Belleville spring 7 Gas supply part 110 Restricting mechanism 111 Push screw 112 nuts

Claims (12)

A film forming process in which a first reaction gas and a second reaction gas that reacts with the first reaction gas to form a reaction product are supplied to the substrate in the processing container. In the device
A placement unit provided in the processing container and provided with a substrate placement region;
A top plate member provided so as to face the mounting portion and forming a processing space for the substrate with the mounting portion;
Between the position where the substrate is delivered to the mounting portion and the position where the mounting portion contacts the top plate member, the mounting portion can be moved up and down relatively with respect to the top plate member. An elevating mechanism for making the mounting portion relatively close to the top plate member during the film forming process and forming an exhaust gap in the circumferential direction of the substrate in the peripheral portion of the substrate or the outer region of the substrate;
It is provided between at least one of the mounting portion and the support portion that supports the mounting portion, and between the top plate member and the support portion that supports the top plate member, and is mounted by the lifting operation of the lifting mechanism. A buffer mechanism for correcting the relative posture of the mounting portion with respect to the top plate member and relaxing the contact pressure when one side of the mounting portion and the top plate member is biased to the other side, and
When the mounting portion and the top plate member are separated from each other, the corrected relative posture is to be restored so that the relative posture of the mounting portion with respect to the top plate member is corrected. A regulation mechanism to suppress the action of
A gas supply unit for supplying the first reaction gas and the second reaction gas to the processing space;
A film forming apparatus comprising: exhaust means for exhausting the processing space through the gap and the atmosphere in the processing container. The processing vessel is a vacuum vessel;
2. The film forming apparatus according to claim 1, wherein the evacuating unit is a evacuating unit for evacuating the processing space through the gap and the atmosphere in the vacuum vessel.   The film forming apparatus according to claim 2, wherein the action of returning the relative posture to an original state is caused by a pressure difference between the inside and the outside of the processing container. The support portion that supports the mounting portion is configured to be movable up and down by an elevating mechanism that supports the mounting portion, and is above or below the flange portion provided on the lower end side of the mounting portion. Provided in
The restriction mechanism includes a lifting shaft provided so as to pass through one side of the flange portion and the support portion and move up and down toward the other side, and a tip of the lifting shaft is in contact with one surface of the other side 4. The film forming apparatus according to claim 1, further comprising: a fixing member that fixes the height position. 5.   5. The film forming apparatus according to claim 4, wherein the elevating shaft is a push screw, and the fixing member is a nut. A film forming process in which a first reaction gas and a second reaction gas that reacts with the first reaction gas to form a reaction product are supplied to the substrate in the vacuum container. In the device
A mounting portion provided in the vacuum container, and having a substrate mounting region;
A top plate member that is provided so as to face the mounting unit and forms a processing space for the substrate with the mounting unit;
Relative to the top plate member between the position where the substrate is transferred to the placement portion and the position where the placement portion is brought close to the top plate member to form the processing space. A lifting mechanism that lifts and lowers automatically,
Provided in at least one of the outer region of the placement region and the top plate member in the placement unit, and when the processing space is formed, the tip contacts with the other, so that between the outer region and the top plate member A projecting portion for forming a clearance of less than 1 mm for exhaust so as to restrict the separation distance and surround the placement region;
A gas supply unit for supplying the first reaction gas and the second reaction gas to the processing space;
And a vacuum evacuation means for evacuating the processing space through the gap and the atmosphere in the vacuum vessel.   Provided between at least one of the mounting portion and the supporting portion that supports the mounting portion, and between the top plate member and the supporting portion that supports the top plate member. A buffer mechanism is provided for correcting the relative posture of the mounting portion with respect to the top plate member and relieving the contact pressure when one side is biased to contact the other side via the protrusion. 6. The film forming apparatus according to 6.   The buffer mechanism includes an elastic member provided between the placement unit and the elevating mechanism, and the elastic member has a top plate with respect to the placement unit in a position where the elevating mechanism forms the processing space. 6. The structure according to claim 1, wherein when the force is applied in a direction approaching the member, a force for returning the mounting portion in a direction away from the top plate member is applied. Or the film forming apparatus according to any one of 7; A detection unit for detecting pressure in the processing space;
The film forming apparatus according to claim 1, further comprising a display unit that outputs a detection value from the detection unit.   10. The control unit according to claim 9, further comprising: a control unit that compares a detection value from the detection unit with a pressure setting range and outputs an alarm signal when the detection value is out of the setting range. Membrane device. A cleaning gas supply unit for supplying a cleaning gas for removing a film attached in the processing space to the processing space;
The detection value from the detection unit is compared with the pressure setting range, and when the detection value is out of the setting range, a control signal is output so that the cleaning gas is introduced into the processing space from the cleaning gas supply unit. The film forming apparatus according to claim 9, further comprising: a control unit that performs the control. A film forming process in which a first reaction gas and a second reaction gas that reacts with the first reaction gas to form a reaction product are supplied to the substrate in the processing container. In the method
The mounting portion provided in the processing container and provided with the substrate mounting region is placed on the top plate member with respect to the top plate member provided to face the mounting portion. A process of relatively raising to make contact,
By the buffer mechanism provided between at least one of the mounting portion and the support portion that supports the mounting portion, and between the top plate member and the support portion that supports the top plate member, the mounting portion and When one side of the top plate member is biased to contact the other side, the step of correcting the relative posture of the mounting portion with respect to the top plate member while relaxing the contact pressure;
When the mounting portion and the top plate member are separated from each other, the corrected relative posture is to be restored so that the relative posture of the mounting portion with respect to the top plate member is maintained in a corrected state. The process of suppressing the action to be performed by the regulation mechanism,
In a state in which the action of the relative posture to return to the original state is suppressed by this restriction mechanism, the mounting portion is brought relatively close to the top plate member, and the substrate is formed at the peripheral portion of the substrate or the outer region of the substrate. Forming a gap for exhaust in the circumferential direction of
Supplying the first reaction gas and the second reaction gas to the processing space;
And evacuating the processing space through the gap and the atmosphere in the processing container.

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