JP5083153B2 - Vacuum processing equipment - Google Patents

Description

  The present invention relates to a vacuum processing apparatus for processing a substrate with a processing gas.

  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. The process of switching and forming one or more atomic layers or molecular layers by the reaction of both gases, and laminating these layers to form a film on the substrate by performing this cycle many times. Are known. This process is called ALD (Atomic Layer Deposition) or MLD (Molecular Layer Deposition), for example, and the film thickness can be controlled with high precision 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 example in which such a film forming method is suitable, for example, film formation of a high dielectric film used for a gate oxide film can be given. For example, when a silicon oxide film (SiO ₂ film) is formed, for example, a Vista butylaminosilane (hereinafter referred to as “BTBAS”) gas or the like is used as the first reaction gas (raw material gas). Oxygen gas or the like is used as the second reaction gas.

As an apparatus for carrying out this film forming method, using a single-wafer film forming apparatus equipped with a gas shower head in the upper center of the vacuum vessel, a reactive gas is supplied from above the central part of the substrate, and an unreacted reaction is performed. A method of exhausting gas and reaction by-products from the bottom of the processing vessel has been studied. In order to improve the throughput, a multi-chamber system that includes a plurality of single-wafer film forming apparatuses and performs processing in each film forming apparatus may be configured. However, this multi-chamber system is configured by providing a gas supply mechanism such as the gas shower head for each vacuum container, and means for controlling the gas supply from the gas supply mechanism into the vacuum container is also provided for each gas supply mechanism. Will be provided respectively. Accordingly, the installation of such a multi-chamber system tends to increase the size and complexity of the equipment, resulting in a problem that the cost of the apparatus increases.
In general, a single-wafer type film forming apparatus includes, for example, a mounting table provided with a substrate mounting region in a vacuum vessel, and a gas shower head having a flat gas discharging surface. It arrange | positions so that it may become parallel with respect to this, It becomes the structure which discharges reaction gas toward a mounting base from a gas shower head. At this time, the reaction gas is supplied to the substrate on the mounting table so that the reaction gas having a predetermined concentration is supplied. As described above, the flat gas discharge surface is set to the substrate mounting surface. When arranged in parallel, there is nothing to block the gas flow around the substrate, so that the reaction gas supplied to the substrate surface immediately flows out into the space in the surrounding reaction vessel. For this reason, for example, if the average concentration of the reaction gas on the substrate surface until the reaction gas is switched is to be kept at a predetermined value or more, the reaction gas must be supplied to compensate for the outflow to the surrounding space, which is expensive. There was a problem that more reactive gas was consumed than necessary.

  In addition, the above film forming method takes a long time to replace the gas with the purge gas, and the number of cycles is, for example, several hundred times. Therefore, the processing time is long, and each time one substrate is processed, it is moved into the processing container. It is necessary to carry in and out the substrate, evacuate the inside of the processing container, etc., and there is a great time loss associated with these operations, and there is a demand for an apparatus and method that can process with high throughput.

  Therefore, for example, as described in Patent Documents 1 and 2, for example, a plurality of substrates are mounted on a circular mounting table in the circumferential direction, and the reaction gas is applied to the substrate on the mounting table while rotating the mounting table. An apparatus for forming a film by switching and supplying it is known. For example, in the film forming apparatus described in Patent Document 1, a plurality of processing spaces that are partitioned in the circumferential direction of the mounting table and supplied with different reaction gases are provided. In the film forming apparatus described in Patent Document 2, the mounting table is provided. For example, two reaction gas supply nozzles that extend in the radial direction above the substrate and discharge different reaction gases toward the mounting table are provided, and the substrate on the mounting table is rotated by rotating the mounting table. By passing through the space or under the reactive gas nozzle, the reactive gas is alternately supplied to each substrate to form a film. This type of deposition system does not have a reactive gas purge process and can process multiple substrates with a single loading / unloading or evacuation operation, thus reducing the time required for these operations and improving throughput. Can be made.

  However, with the recent increase in size of substrates, for example, in the case of a semiconductor wafer (hereinafter referred to as a wafer), film formation is performed on a substrate having a diameter of 300 mm. For this reason, when a plurality of wafers are mounted on a common mounting table, a gap formed between adjacent wafers also becomes relatively large, and the reaction gas is supplied from the reaction gas supply nozzle toward the gap. The reaction gas that does not contribute to film formation is consumed.

  Further, for example, it is assumed that a disc-shaped wafer having a diameter of 300 mm is placed at a position where a circle having a radius of 150 mm is drawn from the center of the mounting table, and the mounting table is rotated at a speed of 60 rpm. In this case, since the moving speed of the mounting table in the circumferential direction differs by about three times between the center side and the peripheral side of the mounting table, the speed of the wafer passing under the reactive gas supply nozzle is also mounted. It will differ up to 3 times depending on the position.

Here, when the concentration of the reaction gas supplied from the reaction gas supply nozzle is constant in the radial direction of the mounting table, it is involved in film formation on the wafer surface as the speed of the wafer passing under the nozzle increases. The amount of reaction gas that can be reduced. For this reason, it supplies from the said nozzle so that the reactive gas density | concentration required for film-forming can be obtained on the wafer surface mounted in the peripheral part of the mounting base where the speed which passes under the reactive gas supply nozzle becomes the fastest. The amount of reaction gas is determined. However, if the reaction gas is supplied in accordance with the required amount of the peripheral portion of the mounting table where the passing speed is the fastest, the reaction gas having a concentration higher than the required amount is supplied to the inner region where the moving speed is slower than the peripheral portion. As a result, the reactive gas not involved in the film formation is exhausted as it is. Here, the source gas used for ALD and the like is often obtained by vaporizing a liquid source or sublimating a solid source, but these sources are expensive. The apparatus consumes such an expensive reactive gas in an amount higher than that required for film formation as the wafer throughput is improved. Therefore, there is a need for a film forming apparatus that consumes less reactive gas while improving the throughput. It was.
Japanese Patent No. 3144664: FIG. 1, FIG. 2, Claim 1 JP 2001-254181 A: FIGS. 1 and 2

  The present invention has been made based on such circumstances, and an object thereof is to provide a vacuum processing apparatus capable of simplifying the structure of the gas supply system and reducing the cost. Another object of the present invention is to provide a vacuum processing apparatus that suppresses consumption of a reaction gas.

Another vacuum processing apparatus of the present invention is a vacuum processing apparatus that performs processing on a substrate using a processing gas in a vacuum vessel.
A plurality of lower members provided in the vacuum container, each including a substrate placement region;
A plurality of upper members that are provided to face each of these lower members, and that form a processing space between the substrate placement region,
An exhaust opening formed along the circumferential direction of the processing space, for communicating the inside of the processing space and the atmosphere in the vacuum vessel outside the processing space;
A processing gas supply mechanism common to a plurality of processing spaces formed by the set of the upper member and the lower member;
A plurality of branch paths for branching from the processing gas supply mechanism via a common gas supply path, and supplying a processing gas to each of the plurality of processing spaces;
A diffusion chamber provided at a downstream end of the common gas supply path, having a cross-sectional area larger than a cross-sectional area of the gas supply path, and having the plurality of branch paths connected to the downstream side;
Evacuation means for evacuating the processing space through the exhaust opening and the atmosphere in the vacuum vessel;
It is provided with.

  The exhaust opening is constituted by, for example, a gap formed in the circumferential direction between the lower edge and the lower member of the upper member. In this case, for example, a plurality of sets of the upper member and the lower member are Arranged along the circumferential direction.

  Further, the common gas supply path is erected and connected, for example, at the center of the upper surface of the diffusion chamber, and the processing gas supply mechanism vaporizes the liquid material into the erected common gas supply path and discharges the processing gas. The length of the supply path of the liquid raw material which connects the storage part for storing the said liquid raw material and the said nozzle is 2 m or less, for example. And the supply path which supplies process gas other than the process gas obtained by vaporizing the said liquid raw material may be connected to the said standing common gas supply path.

The diffusion chamber is provided, for example, immediately above a vacuum vessel, and the processing gas supply mechanism is a mechanism for supplying a first reaction gas and a reaction product on the substrate that reacts with the first reaction gas. A mechanism for supplying a second reaction gas for generating a gas, and a mechanism for supplying a purge gas,
The process gas supply mechanism is controlled so that a purge gas is supplied between the timings of supplying the reaction gas by executing the cycle of supplying the first reaction gas and the second reaction gas alternately to the processing space many times. You may provide the control part for doing. The inner peripheral surface of the upper member may be formed, for example, in a shape that widens toward the bottom from the top, and a gas supply port for supplying a processing gas may be formed in the center of the upper member.

According to the film forming apparatus of the present invention, a processing gas supply mechanism shared by a plurality of processing spaces formed by a set of a lower member including a substrate placement region and an upper member opposed to the lower member, and this processing A plurality of branch passages branched from the gas supply mechanism through a common gas supply passage, respectively, for supplying the processing gas to the plurality of processing spaces, and a diffusion chamber for diffusing the gas upstream of the branch passage And are provided. Therefore, since it is not necessary to provide a gas supply mechanism for each processing space, the structure of the gas supply system can be simplified, and the apparatus equipment can be prevented from becoming large and complicated. As a result, the manufacturing cost of the device can be suppressed. Further, since the gas supply mechanism and the gas supply path are made common, it is possible to perform highly uniform gas processing in each processing space.
According to another invention, the structure of the gas supply system can be simplified as described above, and highly uniform gas processing can be performed in each processing space. In another aspect of the present invention, a set of a plurality of upper members and lower members that form a processing space is provided in the vacuum vessel, and the atmosphere in the vacuum vessel outside the processing space is communicated with the processing space. The air is exhausted through the exhaust opening. Therefore, the volume of the processing space can be reduced as compared with the case where a large-sized rotary table capable of mounting a plurality of substrates is prepared and the processing space is provided on the upper surface side of the rotary table. As a result, since it is not necessary to supply a reactive gas to a region that is not involved in film formation, such as a gap between substrates, it is possible to reduce the supply amount of the reactive gas necessary for the film forming process.

  A film forming apparatus according to an embodiment of the present invention includes a flat vacuum container 1 having a substantially circular planar shape as shown in FIG. 1 (longitudinal sectional view along line II ′ in FIG. 2) to FIG. And a plurality of, for example, five mounting tables 2 disposed in the vacuum container 1 along the circumferential direction of the vacuum container 1, and provided at positions facing these mounting tables 2, And a top plate member 22 that is an upper member for forming a processing space between the mounting table 2 and the mounting table 2. In this example, the mounting table 2 constitutes a lower member having a substrate mounting area. The vacuum vessel 1 is configured so that the top plate 11 and the bottom plate 14 can be separated from the side wall portion 12, and the top plate 11 and the bottom plate 14 are brought into an airtight state on the side wall portion 12 via a sealing member, for example, an O-ring 13. While being maintained, it is fixed by a fastener (not shown) such as a screw.

  When separating the top plate 11 and the bottom plate 14 from the side wall portion 12, the top plate 11 can be lifted by a drive mechanism (not shown), and the bottom plate 14 can be lowered by a lifting mechanism described later.

  The mounting table 2 is a circular plate member made of, for example, aluminum or nickel, and the diameter of the mounting table 2 is slightly larger than a wafer W having a diameter of, for example, 300 mm, which is a substrate processed by the film forming apparatus. Is formed. A recess 26 is provided on the upper surface of each mounting table 2, which serves as a mounting area (mounting surface) for mounting the wafer W. Each stage 2 is embedded with a stage heater 21 that constitutes a heating means composed of, for example, a sheet-like resistance heating element for heating the wafer W on the mounting surface. The wafer W on the mounting table 2 can be heated to, for example, about 300 ° C. to 450 ° C. by the supplied electric power. If necessary, an electrostatic chuck (not shown) may be provided in the mounting table 2 so that the wafer W mounted on the mounting table 2 can be electrostatically attracted and fixed. In FIG. 3, for convenience, the wafer W is drawn on only one mounting table 2.

  Each mounting table 2 is supported by a support arm 23 at the center on the bottom surface side, and the base end side of these support arms 23 is connected to the top of a column 24 that vertically penetrates the center of the bottom plate 14. Yes. In this example, for example, five support arms 23 extend substantially horizontally with the tip side supporting the mounting table 2 facing the radial direction of the vacuum vessel 1, and the adjacent support arms 23 are substantially equal in the circumferential direction. They are arranged radially at angular intervals. As a result, as shown in FIGS. 2 and 3, the mounting table 2 supported at the tip of the support arm 23 is also arranged around the support column 24 at equal intervals along the circumferential direction of the vacuum vessel 1. Thus, the center of each mounting table 2 is located on the circumference of a circle centered on the column 24.

  The lower end side of the column 24 penetrating the bottom plate 14 is connected to the drive unit 51, and all the mounting tables 2 connected to the column 24 can be moved up and down simultaneously via the support arm 23. That is, in this example, the support arm 23, the support column 24, and the drive unit 51 constitute a common lifting means for each mounting table 2. Further, the drive unit 51 also has a role as a rotating means that can rotate the support column 24 around the vertical axis, for example, so that the mounting table 2 supported by the support arm 23 is circumferentially moved around the vertical axis. Can be moved to. Further, the sleeve 25 shown in FIG. 1 serves to store the support column 24 and maintain the airtight state of the vacuum vessel 1, and the magnetic seal 18 is used to create an atmosphere in the space surrounded by the support column 24 and the sleeve 25 and the vacuum vessel 1. It plays the role of airtightly partitioning the atmosphere inside.

  As shown in FIGS. 2 and 3, the side wall 12 of the vacuum vessel 1 has a transfer port for transferring the wafer W between the transfer arm 101 which is an external substrate transfer means and each mounting table 2. A port 15 is formed, and the transport port 15 is opened and closed by a gate valve (not shown). Each mounting table 2 can move in the circumferential direction in the vacuum vessel 1 by rotating the support column 24, and sequentially stop at a position facing the transfer port 15 to transfer the wafer W. The bottom plate 14 on the lower side of the delivery position projects and sinks from the mounting surface through a through hole (not shown) provided in each mounting table 2, and lifts the wafer W from the back surface side to transfer the transfer arm 101 and each mounting plate. For example, three elevating pins 16 for delivering to and from the mounting table 2 are provided. The raising / lowering pin 16 is supported by the raising / lowering plate 53 at the bottom, and the raising / lowering plate 53 can be moved up and down by the drive unit 52 to raise and lower the entire raising / lowering pin 16. The bellows 17 covers the lifting pins 16 and is connected to the bottom surface of the bottom plate 14 and the lifting plate 53, and plays a role of maintaining an airtight state in the vacuum vessel 1.

  On the lower surface of the top plate 11 of the vacuum vessel 1, for example, five top plate members 22 of the same number as the mounting table 2 so as to be arranged in the circumferential direction around the center of the vacuum vessel 1 like the mounting table 2 described above. When the film formation is performed, each top plate member 22 forms a processing space 20 so as to face one mounting table 2, and five sets (the mounting table 2 and the top plate member 22 are connected to each other). Group). Here, as described above, the mounting table 2 is configured to be movable in the circumferential direction around the support column 24. Therefore, the mounting table 2 is set at a predetermined position (hereinafter, this position is referred to as a "processing position"). In this case, the top plate member 22 is opposed to the corresponding mounting table 2.

  As shown in FIG. 4, each top plate member 22 has a bottom surface of a cylindrical body having a flat surface on the top surface that is continuously depressed from the peripheral edge toward the center, and is expanded toward the bottom from the top. And a main body portion 22a formed with a concave surface (a trumpet-shaped concave portion) having a conical shape, and an outer periphery of the main body portion 22a so as to closely surround it, and its lower end surface is a flat surface. And a sleeve 22b formed to have the same height as the peripheral edge of the main body portion. The main body portion 22a and the sleeve 22b are made of, for example, aluminum. The concave portion is opened in a circular shape having a diameter that is slightly larger than the wafer W so as to cover the entire wafer W placed on the placement table 2, for example, and is placed from the lower end of the top plate member 22. The distance to the top surface of 2 is “h”. Since the bottom surface of the sleeve 22 b is at the same height as the lower end of the top plate member 22, when the mounting table 2 is opposed to the top plate member 22, the lower edge of the top plate member 22 and the mounting table 2 are A gap having a width “h” is formed between them in the circumferential direction.

  Thus, by arranging the top plate member 22 having the concave portion and the disk-like mounting table 2 so as to face each other, for example, in this example, a cone is provided between the mounting table 2 and the top plate member 22. A shaped space is formed. In the film forming apparatus according to the present embodiment, these spaces serve as a processing space 20 in which film formation is performed by switching and diffusing a plurality of types of reactive gases and adsorbing and reacting on the surface of the wafer W. Various gases supplied into the processing space 20 enter the vacuum container 1 through the gap formed between the mounting table 2 and the top plate member 22 along the circumferential direction of the processing space 20. It will be leaked. In the film forming apparatus according to the present embodiment, the gap communicates the inside of the processing space 20 with the atmosphere in the vacuum vessel 1 that is outside the processing space 20 (corresponding to an exhaust space 10 described later). This corresponds to the exhaust opening.

  A gas supply port 221 is formed at the top of the conical recess of each top plate member 22, and a reaction gas and a purge gas for purging the reaction gas are supplied into the processing space 20 from the gas supply port 221. Is done.

  On the central portion of the top plate 11, a manifold portion 3 for supplying gas to each processing space 20 is provided. The manifold section 3 includes a vertical cylindrical flow path member 31a that forms a gas supply path 32, and a large-diameter flat cylindrical member 31b in which the downstream end of the gas supply path 32 is connected to the center of the upper surface thereof. It has. The cylindrical member 31 b constitutes a gas diffusion chamber 33 for diffusing the gas introduced from the vertical gas supply path 32 and supplying the gas to the five gas supply pipes 34.

  The gas supply pipes 34 are configured in the same manner, and extend radially from the side wall of the large-diameter cylindrical member 31b at substantially equal angular intervals in the circumferential direction. The downstream end of each gas supply pipe 34 is connected to the gas supply port 221.

  The flow path member 31a is provided with an injector 4 for supplying a liquid source, which is a source of a first reaction gas such as BTBAS, which generates a source gas for vapor deposition to form a film, from the lateral direction to the gas supply path 32. It has been. The source gas will be described in detail later. A liquid source supply pipe 713 is connected to the injector 4, and the upstream side of the supply pipe 713 stores a liquid source such as BTBAS via a pump 711 whose operation is controlled by a control unit 100 described later. The source gas supply source 71 is connected. The source gas supply source 71 is disposed, for example, above the injector 4 to suppress an increase in the supply path from the source gas supply source 71 to the injector 4. With such an arrangement, the deterioration of the liquid material, that is, the decrease in the concentration of BTBAS in the liquid material due to volatilization or decomposition is suppressed, thereby reducing the operating cost of the apparatus. In this way, in order to suppress the deterioration of the liquid material, the length of the supply pipe between the material gas supply source 71 and the injector 4 is configured to be 2 m or less, for example.

  As the injector 4, a conventionally known one is used, and the main part of the configuration will be briefly described below with reference to FIG. 6 which is a longitudinal sectional view. The injector 4 includes a main body 41, and a supply passage 42 through which the liquid raw material is supplied is provided in the main body 41 in the length direction thereof. The arrows in the figure indicate the flow of the liquid raw material, and the liquid raw material flows through the supply passage 42 while being pressurized by the pump 711.

  A filter 44 </ b> A for purifying the liquid film forming material is provided on the upstream side of the supply passage 42. The downstream side of the supply passage 42 is reduced in diameter to form a reduced diameter portion 42A, and a discharge port 45 that is opened and closed by a needle valve 44 is formed at the downstream end of the reduced diameter portion 42A. The needle valve 44 is urged toward the downstream side by a return spring 47 via a plunger 46, thereby contacting the reduced diameter portion 42 </ b> A and closing the discharge port 45. A solenoid 48 provided so as to surround the plunger 46 is connected to a current supply unit 49 and functions as an electromagnet when supplied with a current. The current supply unit 49 receives a control signal from the control unit 100 and controls supply / disconnection of the current to the solenoid 48.

  When a current is supplied to the solenoid 48 and a magnetic field is formed around it, the plunger 46 is pulled upstream of the supply passage 42 and at the same time, the needle valve 44 is pulled upstream to open the discharge port 45. The liquid raw material stored in a pressurized state in the supply passage 42 is discharged from the discharge port 45 to the gas supply passage 32. A portion surrounded by a large dotted circle in the figure is such that the discharge port 45 is thus opened, and the state when the liquid material is discharged from the discharge port 45 to the gas supply path 32 is shown in an enlarged manner.

  Since the gas supply path 32 is decompressed when the liquid material is discharged by the injector 4 as described above, the liquid material is boiled under reduced pressure to become a gas, and the gas flows downstream. When the formation of the magnetic field by the solenoid 48 is stopped, the plunger 46 is pushed back downstream by the return spring 47 and the discharge port 45 is closed by the needle valve 44. The amount of the first reaction gas generated in the gas supply path 32 is controlled by the pressure of the pump 711 and the opening time of the discharge port 45. In addition to supplying the liquid raw material from the injector 4 to the decompressed gas supply path 32 for vaporization, a vaporizer is provided in the supply pipe 713 and the liquid raw material is supplied to the flow space by the vaporizer. It may be vaporized in advance to generate a reaction gas, and the reaction gas may be supplied to the supply path 32.

In addition to the supply pipe 713 for supplying the liquid raw material, the manifold section 3 is connected with gas supply pipes 723 and 733 for supplying various gases to the gas supply path 32 as shown in FIG. These pipes 723 and 733 are respectively connected to various gas supply sources 72 and 73 on the upstream side. In this example, the gas supply pipes 723 and 733 are connected to the manifold portion 3 so that each gas can be supplied to the gas supply path 32 from a direction different from the direction in which the liquid raw material is supplied by the injector 4.
The film formation apparatus according to the present embodiment includes metal elements, for example, Ti, Cr, Mn, Fe, Co, which are elements of the fourth period of the periodic table, such as Al and Si, which are elements of the third period of the periodic table. Ba, Hf, Ta, W, which are elements of the sixth period of the periodic table, such as Zr, Mo, Ru, Rh, Pd, Ag, which are elements of the fifth period of the periodic table, such as Ni, Cu, Zn, Ge, etc. It is possible to form a thin film containing elements such as Re, lr, and Pt, and as a metal raw material to be adsorbed on the surface of the wafer W, an organic metal compound or an inorganic metal compound of these metal elements is used as a reactive gas (hereinafter, As a raw material gas). Specific examples of the metal raw material include, in addition to the above-mentioned BTBAS, DCS [dichlorosilane], HCD [hexadichlorosilane], TMA [trimethylaluminum], 3DMAS [trisdimethylaminosilane], and the like.

In addition, 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 organic acids, alcohols such as 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 , NH ₃ , Various reactions such as a nitriding reaction using NH ₂ NH ₂ , N ₂ or the like can be used. In the present embodiment, an example will be described in which a BTBAS gas exemplified in the background art is used as a source gas and an SiO ₂ film is formed by an oxidation reaction using oxygen gas.

  The oxygen gas supply pipe 723 is connected to the oxygen gas supply source 72, and the purge gas supply pipe 733 is connected to the purge gas supply source 73. The oxygen gas that is the second reaction gas and the argon gas that is the purge gas are already supplied. The gas can be supplied to the gas supply path 32 described above. Here, the supply pipes 723 and 733 for supplying these oxygen gas and argon gas to the gas supply path 32 are opened and closed including, for example, diaphragm-type pressure regulating valves 721 and 731 and electromagnetic valves employing, for example, disk-type plungers. Valves 722 and 732 are interposed so that various gases at a constant pressure can be supplied at a large flow rate and at a high response speed.

A pump 711, pressure regulating valves 721 and 731, and on-off valves 722 and 732 connected to these gas supply sources 71 to 73 constitute a gas supply control unit 7 of the film forming apparatus. The supply timing of various gases and the like can be controlled based on the instruction.
Also, in this example, among the components described above, the source gas supply source 71, the pump 711, the source gas supply pipe 713, the injector 4, the manifold section 3, and the gas supply pipe 34 are the first reactive gas supply section. The oxygen gas supply source 72, the pressure adjustment valve 721, the on-off valve 722, the oxygen gas supply pipe 723, the manifold part 3 and the gas supply pipe 34 correspond to the second reaction gas supply part, and the purge gas supply source 73, the pressure regulating valve 731, the on-off valve 732, the purge gas supply pipe 733, the manifold section 3, and the gas supply pipe 34 correspond to the purge gas supply section.

A remote plasma supply unit 54 for supplying plasma gas into the processing space 20 is provided above the flow path member 31a. In performing the maintenance of the apparatus, when the NF ₃ gas is supplied to the processing space 20 while exhausting as will be described later, the remote plasma supply unit 54 converts the NF ₃ gas into plasma to generate plasma. Then, the deposit in the processing space 20 is removed from the wall surface of the processing space 20 by this plasma, and is removed from the processing space 20 by riding on the exhaust flow formed in the processing space 20. Incidentally, instead of the remote plasma supply unit 54, the injector 4 may be provided on the upper side of the flow path member 31a, and the liquid raw material may be supplied from the injector 4 along the direction in which the gas supply path 32 of the flow path member 31a is formed.

  Returning to the description of the vacuum vessel 1, as shown in FIGS. 1 and 3, for example, the bottom plate 14 is used to exhaust each reaction gas and purge gas at a position opposite to the transfer port 15 with the support 24 interposed therebetween. The common exhaust port 61 is provided. The exhaust port 61 is connected to an exhaust pipe 62, and the exhaust pipe 62 is connected to a vacuum pump 64 that constitutes a vacuum exhaust means via a pressure adjusting means 63 that adjusts the pressure in the vacuum vessel 1. Here, in the vacuum vessel 1, as described above, the five sets of mounting tables 2 and the top plate member 22 that constitute the processing space 20 in which film formation is performed are arranged, and flowed out of these processing spaces 20. Various gases are exhausted to the common exhaust port 61 through the inside of the vacuum container 1, so that the vacuum container 1 constitutes an exhaust space 10 for the reaction gas. That is, it can be said that the film forming apparatus according to the present embodiment has a structure in which a plurality of processing spaces 20 are arranged in a common exhaust space 10.

  The film forming apparatus having the above-described structure includes a gas supply operation from the gas supply sources 71 to 73 described above, a rotation and elevation operation of the mounting table 2, an exhaust operation of the vacuum vessel 1 by the vacuum pump 64, and each stage heater. The control part 100 which controls the heating operation by 21 etc. is provided. The control unit 100 includes, for example, a computer including a CPU and a storage unit (not shown). The storage unit includes controls necessary for film formation on the wafer W by the film formation apparatus, for example, gas supply sources 71 to 73. Steps relating to control of supply / disconnection of various gases from the gas, control of supply amount adjustment, control of adjusting the degree of vacuum in the vacuum vessel 1, raising / lowering of the mounting table 2, rotation operation control, temperature control of each stage heater 21, etc. A program in which (instruction) groups are assembled is recorded. 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 is installed in the computer therefrom.

  Hereinafter, the operation of the film forming apparatus according to the present embodiment will be described. First, as shown in FIG. 8 in a state where the mounting table 2 is lowered to the delivery position of the wafer W, the transfer port 15 is opened by a gate valve (not shown), and the external transfer arm 101 is advanced from the transfer port 15 to enter the vacuum container 1. The wafer W is loaded into the inside. At this time, at the position facing the transfer port 15 in the vacuum container 1 (the delivery position of the wafer W), the mounting table 2 on which the wafer W is placed next is waiting by rotating the support 24. Then, the lifting pins 16 protrude from the mounting table 2 through a through hole (not shown), the wafer W is transferred from the transfer arm 101 to the lifting pins 16, the transfer arm 101 is retracted out of the vacuum container 1, and then the lifting pins 16 are mounted. The wafer W is placed in the recess 26 which is a placement surface by being immersed below the placement table 2. The wafer W is attracted and fixed by an electrostatic chuck (not shown).

  In this way, after the operation of sequentially placing the wafers W on the five mounting tables 2 is repeated and the loading of the wafers W is completed, each mounting table 2 is moved to the processing position and opposed to the top plate member 22. Stop. At this time, the mounting table 2 is preheated to, for example, 300 ° C. to 450 ° C. by the stage heater 21, and the wafer W is heated by being mounted on the mounting table 2. Then, the mounting table 2 that has been lowered to the loading position of the wafer W is raised and stopped, for example, at a height position selected in the deposition recipe.

  Here, the film forming apparatus according to the present embodiment adjusts the height position at which the mounting table 2 is stopped, thereby adjusting the width of the gap formed between the mounting table 2 and the top plate member 22 (the size of the gap). For example, in the range of “h = 1 mm to 6 mm”. For example, FIG. 9A shows a case where the width of the gap is “h = 4 mm”, and FIG. 9B shows a case where the width of the gap is “h = 2 mm”.

  After each mounting table 2 is made to face the top plate member 22 and the width of the gap is adjusted in this way, the transfer port 15 is closed to make the inside of the vacuum vessel 1 airtight, and then the vacuum pump 64 is operated to perform vacuum. The inside of the container 1 is set to a draw state. Then, the inside of the vacuum chamber 1 is evacuated to a predetermined pressure, for example, 13.3 Pa (0.1 Torr), and the film formation is started when the temperature of the wafer W is raised to, for example, 350 ° C. of the above-described temperature range.

  In a so-called ALD process using the film forming apparatus according to the present embodiment, film formation is performed based on, for example, a gas supply sequence shown in FIGS. 10 (a) and 10 (b). 10A and 10B show the case where the width of the gap between the mounting table 2 and the top plate member 22 is “h = 4 mm” (corresponding to FIG. 9A), and “h = It is the schematic diagram which showed the gas supply sequence in the case of 2 mm "(corresponding | compatible to FIG.9 (b)). In these drawings, the horizontal axis indicates time, and the vertical axis indicates the pressure in the processing space 20.

  For example, looking at the case of FIG. 10A (h = 4 mm), first, the raw material (gas first reaction gas: BTBAS) is supplied into each processing space 20 and is adsorbed to the wafer W on the mounting table 2. (Source gas adsorption step: hereinafter abbreviated as “adsorption step”. In FIG. 10A, “a step” is described). At this time, the BTBAS liquid source stored in the source gas supply source 71 is discharged to the reduced pressure gas supply path 32 by, for example, opening the discharge port 45 of the injector 4 for 1 ms, for example, and boiled under reduced pressure. The BTBAS gas, which is the first reaction gas, is supplied to the downstream gas diffusion chamber 33 as shown by the arrow in FIG. The BTBAS gas diffuses in the gas diffusion chamber 33 and travels downstream.

  Then, the vaporized source gas is introduced into each processing space 20 via the gas supply port 221, and thereby the pressure in the processing space 20 is, for example, 133.32 Pa as shown in step a in FIG. Rise to (1 Torr). On the other hand, since each processing space 20 is disposed in the exhaust space 10 as described above, the source gas supplied into the processing space 20 is directed toward the exhaust space 10 having a lower pressure than that in the processing space 20. The air flows out into the exhaust space 10 through the gap between the mounting table 2 and the top plate member 22.

  As a result, as shown in FIG. 12, the source gas is supplied into the processing space 20 from the top of the conical processing space 20, that is, the gas supply port 221 provided above the center of the wafer W. The surface of the wafer W flows in the radial direction toward the gap while expanding inside, and during this time, it is adsorbed on the surface of the wafer W to form a BTBAS molecular layer. As the source gas supplied intermittently is exhausted from the processing space 20 toward the exhaust space 10, the pressure in the processing space 20 decreases as shown in step a of FIG. .

Next, for example, the raw material staying in the processing space 20 at a timing at which the pressure in the processing space 20 becomes substantially the same as that before the introduction of the raw material gas, for example, at a timing when a predetermined time has elapsed since the supply of the raw material gas. Turning to purging the gas _{(b 1} process of FIG. 10 (a)). Here, for example, the pressure regulating valve 731 provided downstream of the purge gas supply source 73 is adjusted so that the secondary pressure on the outlet side is kept constant at 0.1 MPa, and the on-off valve 732 applies this pressure on the inlet side. In the closed state. And When b ₁ "open" at the start timing of the on-off valve 732 only between eg 100ms step, the pressure balance in front and rear the on-off valve 732, and a purge gas manifold portion 3 in an amount corresponding to the opening time of the switch valve 732 To the processing space 20.

As a result, as in the case of the source gas, as shown in FIG. 12, the purge gas flows on the surface of the wafer W while spreading in each conical processing space 20, and together with the source gas remaining in the processing space 20, the mounting table 2 and the top plate member 22 are exhausted toward the exhaust space 10 through a gap. At this time, the pressure in the processing space 20, as shown in _{b 1} step of FIG. 10 (a), elevated example to 666.7Pa (5Torr) depending on the amount of purge gas supplied by the opening and closing operation of the opening and closing valve 732 The purge gas decreases as it is exhausted toward the exhaust space 10.

  In order to oxidize the raw material gas adsorbed on the wafer W at the timing when the raw material gas staying in the processing space 20 is exhausted together with the purge gas, for example, at a timing when a predetermined time has elapsed after supplying the purge gas, A step of supplying oxygen gas as the second reaction gas into the processing space 20 is executed (hereinafter referred to as “oxidation step”, step c in FIG. 10A). For example, the pressure adjustment valve 721 provided downstream of the oxygen gas supply source 72 is adjusted so that the secondary pressure on the outlet side is 0.1 MPa, similarly to the pressure adjustment valve 731 for the purge gas. It is “closed” when this pressure is applied to the inlet side. When the opening / closing valve 722 is opened for 100 ms, for example, at the start timing of step c, oxygen gas in an amount corresponding to the pressure balance before and after the opening / closing valve 722 and the time for opening the opening / closing valve 722 opens the manifold portion 3. To the processing space 20.

As in the case of the gas supply so far, as shown in FIG. 12, the oxygen gas flows on the surface of the wafer W while expanding the conical processing space 20, and oxidizes the source gas adsorbed on the surface of the wafer W. As a result, a molecular layer of SiO ₂ is formed. At this time, the pressure in the processing space 20 rises to 666.7 Pa (5 Torr) according to the amount of oxygen gas supplied by the opening / closing operation of the opening / closing valve 722, as shown in step c of FIG. The purge gas decreases as it is exhausted toward the exhaust space 10.

Subsequently, for example, the timing at which the pressure of the processing space 20 is substantially the same pressure as before oxygen gas introduction, for example, oxygen gas at predetermined time has elapsed timing from the supply, in the same way as already described b ₁ step Te purge gas supply to purge oxygen gas staying in the processing space 20 (b ₂ steps). Then, as shown in FIG. 10 (a), when the above-described four steps are defined as one cycle, the cycle is repeated a predetermined number of times, for example, 125 times, and the molecular layer of SiO ₂ is multilayered, for example, 10 nm. The film formation having a film thickness is completed. Note that FIG. 10A and FIG. 10B described later schematically show the pressure pattern in the processing space 20 in each step for convenience of explanation, and the strict pressure in the processing space 20 is shown. It does not indicate.

  When the film formation is completed, the gas supply is stopped, the mounting table 2 on which the wafer W is mounted is lowered to the transfer port 15, the pressure in the vacuum vessel 1 is returned to the state before the vacuum exhaust, In the reverse path, the wafer W is unloaded by the external transfer arm 101, and a series of film forming operations is completed.

  In the film forming apparatus according to the present embodiment that forms a film based on the operation described above, the reactive gas is supplied from the common manifold section 3 to the five processing spaces 20 and directed toward the common exhaust space 10. Thus, the reaction gas is exhausted from each processing space 20. For this reason, it may be considered that there is a slight difference in the amount of reaction gas supplied between the five processing spaces 20. However, since this film forming apparatus employs an ALD process that utilizes adsorption of a reactive gas to the surface of the wafer W, even if there is a slight deviation in the amount of reactive gas supplied to each processing space 20, If a sufficient amount of reaction gas capable of forming a molecular layer can be supplied to the surface of the wafer W, a film having a uniform film quality such as a film thickness between the wafer W surfaces can be formed.

  Further, as described above, the film forming apparatus according to the present embodiment can change the gap between the mounting table 2 and the top plate member 22 in the range of “h = 1 mm to 6 mm”, which has been described so far. FIG. 10A shows a gas supply sequence in the case of “h = 4 mm” (FIG. 9A). Therefore, as shown in FIG. 9B, the effect of the film forming apparatus and the influence on the gas supply sequence when “h = 2 mm” is set and the gap between the mounting table 2 and the top plate member 22 is narrowed will be described below. Explained.

  Now, for example, after the supply amount of the source gas from the injector 4 is adjusted so that the pressure in the processing space 20 becomes constant (for example, the pressure P1), the gap between the mounting table 2 and the top plate member 22 is narrowed. Since the pressure loss when the gas passes through the gap increases, the exhaust speed of the gas from the processing space 20 to the exhaust space 10 decreases, and the residence time of the reaction gas in the processing space 20 increases. When the state of the pressure change in the processing space 20 at this time is schematically represented, as shown in FIG. 13A, the pressure in the processing space 20 before the gap is narrowed is as indicated by a solid line “S1”. While the pressure decreases sharply in a short time, the pressure after the gap is narrowed gently decreases as shown by the broken line “S2”. Here, the horizontal axis T in FIGS. 13A to 13C indicates time, and the vertical axis P indicates the pressure in the processing space 20.

  Next, the supply amount of the raw material gas from the injector 4 is adjusted so that the pressure in the processing space is lower than the pressure “P1” (for example, the pressure P2), and similarly the mounting table 2 and the top plate member When the gap with the gap 22 is changed, the pressure in the processing space 20 before and after the gap is narrowed is larger than that shown in FIG. 13 (a), as schematically shown in FIG. 13 (b). Although the overall change is gentle, before the gap is narrowed, the pressure drops in a relatively short time as shown by a solid line “S3”, and after the gap is narrowed, it is relatively long as shown by a broken line “S4”. Decreases over time.

  Thus, in the film forming apparatus according to the present embodiment, both the width “h” of the gap between the mounting table 2 and the top plate member 22 and the supply amount of the source gas from the injector 4 are adjusted. Accordingly, the supply time of the source gas is short, the supply pattern that requires a relatively large amount of source gas (corresponding to the solid line “S1” in FIG. 13C), the supply time of the source gas is long, Adjust at least one of the pressure in the processing space 20 or the residence time of the source gas in the processing space 20 such as a supply pattern (corresponding to the broken line “S4” in the figure) that requires less gas consumption. Thus, the source gas supply pattern can be freely changed.

  Here, in the gas supply sequence shown in FIG. 10B, the area of the triangle of time vs. pressure formed in step a by fixing the gap at “h = 2 mm” and changing the supply amount of the source gas. However, the supply amount of the source gas is determined so as to be equal to the area of the triangle formed in step a of FIG.

The reason why the supply amount of the source gas is determined so that the areas of the triangles formed in FIGS. 10A and 10B are equal is that the ALD process uses the source gas to the surface of the wafer W. This is because it is considered that the film quality such as the film thickness depends on the number of collisions of the source gas molecules with the surface of the wafer W because it is a film forming technique using adsorption. The collision frequency of the source gas molecules to the surface of the wafer W increases in proportion to the pressure in the processing space 20, that is, the concentration of the source gas supplied to the processing space 20, and the total number of collisions during the film formation period is the collision frequency. Since it is a value obtained by time integration, it is considered that the film quality before and after changing the width of the gap can be kept uniform by equalizing the integrated value, that is, the area of the triangle described above. In the gas supply sequence of FIG. 10B, the supply amount of each gas is determined based on the same concept for the c process and the b ₁ and b ₂ processes.

  Here, the supply amount of each gas can be adjusted by increasing / decreasing the time during which the injector 4 and the on-off valves 722 and 732 are “open”. The area of the triangle in the gas supply sequence before changing the width of the gap (in this example, the sequence shown in FIG. 10A in the case of “h = 4 mm”) is good film quality by, for example, preliminary experiments. It is determined by grasping in advance the gas supply amount that can be obtained. When changing the width of the gap, the method for determining the gas supply sequence shown in FIG. 10B is not limited to the above-described method, and a preliminary experiment is performed by changing the width of the gap. The gas supply sequence suitable for the width of each gap may be determined by performing the experiment and obtaining the optimum gas supply amount for the width of each gap.

  If the gas supply sequence when the width of the gap is changed based on the method exemplified above is determined, for example, the change in the film formation time due to the change in the width of the gap, that is, the profit due to the change in the throughput It is preferable to determine the width of the gap so that, for example, these balances are maximized, and the influence on the cost due to changes in various gas consumptions is compared. The determination of the width between the mounting table 2 and the top plate member 22 is performed, for example, when the operation of the film forming apparatus is started or when the process conditions such as the raw material gas are changed.

  The film forming apparatus according to the present invention has the following effects. A mounting table 2 including a mounting region in an apparatus for forming a film by so-called ALD (or MLD) by alternately supplying source gas (first reaction gas) and oxygen gas (second reaction gas) to the wafer W. And the top plate member 22 are opposed to each other to form a processing space 20, and a plurality of sets of the mounting table 2 and the top plate member 22 are arranged in a common vacuum vessel 1, and the mounting table 2 and the top plate 22 are The processing space 20 is evacuated through a gap formed between the plate member 22 and the plate member 22. For this reason, the volume of the processing space 20 can be reduced as compared with the case where a large-sized rotary table capable of mounting a plurality of wafers W is prepared and the processing space is provided on the upper surface side of the rotary table. . As a result, it is not necessary to supply a reaction gas to a region that is not involved in film formation, such as a gap between wafers W, so that it is possible to reduce the supply amount of reaction gas necessary for film formation processing. However, since the volume of the processing space 20 is small, the supply time and exhaust time of the reaction gas to the space are also reduced, and the total film formation time is shortened. It can also contribute to the improvement of the throughput of the apparatus.

  Further, since this film forming apparatus is configured to supply a reactive gas to the wafer W in a stationary state, a type that rotates a mounting table on which a plurality of wafers W described in the background art are mounted. Unlike the film forming apparatus, unnecessary reaction gas consumption due to the difference in the moving speed of the wafer W between the rotation center side and the peripheral side of the mounting table does not occur.

  Next, according to the film forming apparatus according to the present invention including the lifting mechanism (support arm 23, support column 24, drive unit 51) that lifts and lowers the mounting table 2 that forms the processing space 20, the following effects are obtained. The wafer W is placed in the processing space 20 formed between the concave surface of the top plate member 22 and the mounting table 2, and the size of the gap formed between these members 2 and 22 is adjusted. Thus, the pressure in the processing space 20 and the residence time of various reaction gases in the processing space 20 can be adjusted. For this reason, conditions necessary for forming a film on the surface of the wafer W can be created in the narrow processing space 20, so that, for example, the gas shower head having a flat gas discharge surface described in the background art is mounted. Compared with a film forming apparatus in which a reaction gas is supplied by being arranged in a vacuum vessel so as to be parallel to the mounting table, film formation can be performed with less reaction gas.

  Further, since the width of the gap between the mounting table 2 and the top plate member 22 can be changed, the effect of shortening the film formation time by increasing the width of the gap, that is, improving the throughput, and the width. It is possible to select the most suitable gap width for the process, for example, by comparing the effect of reducing the raw material gas consumption by narrowing the gas flow, thereby improving the flexibility of the apparatus.

  Here, in the above-described embodiment, in each gas supply sequence shown in FIG. 10A and FIG. 10B, the mounting table 2 and the top in each step of the adsorption process, the purge process, and the oxidation process. Although the width between the plate member 22 is constant, the operation of the film forming apparatus according to the present embodiment is not limited to this example. For example, by changing the width of the gap in the adsorption process and the oxidation process, and changing the pressure in the processing space 20 and the residence time of the reaction gas according to the type of reaction gas supplied in each process, a high quality film May be formed.

  Note that the method of changing the width of the gap is not limited to the method of raising and lowering the mounting table 2 shown in the above-described embodiment. For example, the top plate member 22 may be configured to be able to be lowered from the top plate of the vacuum vessel 1, and the top plate member 22 may be moved up and down to change the width of the gap, or between the mounting table 2 and the top plate member 22. Both may be raised and lowered.

Next, the invention relating to the manifold portion 3 of the present embodiment has the following effects. Each gas supplied from the injector 4 and the gas supply pipes 723 and 733 as the processing gas supply mechanism passes through the common gas supply path 32, diffuses in the gas diffusion chamber 33, and passes through the gas supply pipe 34 to each processing space 20. Therefore, the number of parts can be reduced as compared with the case where a processing gas supply mechanism is individually provided for each processing space 20, and the structure of the gas supply system is simplified. And complications can be prevented. Thereby, the manufacturing cost of the apparatus can be reduced.
The processing space 20 to which each gas is supplied is composed of the top plate member 22 and the mounting table 2 and is exhausted through a gap formed therebetween. Therefore, the volume of the processing space 20 can be reduced compared to the case where a large-sized rotary table capable of mounting a plurality of substrates is prepared and the processing space is provided on the upper surface side of the rotary table. Since it is not necessary to supply a reactive gas to a region that is not involved in film formation, such as a gap between them, it is possible to reduce the supply amount of the reactive gas necessary for the film forming process. Moreover, since each gas is supplied to the processing space 20 from each common gas supply source through the common gas supply path 32 and the gas diffusion chamber 33, the gas flow rate and the gas concentration supplied to each processing space 20 vary. Is suppressed. Therefore, variations in film quality and film thickness of the wafer W processed in each processing space 20 can be suppressed.

  Furthermore, since the gas diffusion chamber 33 is provided immediately above the vacuum vessel 1 that accommodates the processing space 20, the gas flow path from the gas diffusion chamber 33 to the processing space 20 can be shortened. As a result, re-liquefaction of the BTBAS gas until reaching the processing space can be suppressed, and a large amount of gas can be easily supplied to the processing space 20 in a short time. it can. The length of the flow path from the gas diffusion chamber 33 to each processing space 20 is, for example, 0.3 m to 1.0 m.

  Here, in the film forming apparatus according to the present invention, as shown in FIGS. 1 to 7, a set of the mounting table 2 and the top plate member 22 is arranged in the circumferential direction in a flat cylindrical vacuum vessel 1. It is not limited to (when the center of each mounting table 2 is positioned on the circumference of a circle having the same center as that of the vacuum vessel 1). For example, as in the film forming apparatus shown in FIGS. 14A and 14B, the wafer W mounting regions are provided in a horizontal row on the elongated rectangular mounting table 2 so as to face these mounting regions. Thus, the top plate member 22 may be provided, and these members may be stored in the vacuum container 1 that forms the exhaust space 10 having the common exhaust port 61. Further, as in the film forming apparatus shown in FIG. 15, a plurality of sets of the mounting table 2 and the top plate member 22 facing each other are arranged in the vertical direction, and these are stored in the vacuum container 1 forming the exhaust space 10. Also good. It should be noted that in each example such as the film forming apparatus described below and the mounting table 2 including the example, the constituent elements that play the same role as the film forming measures shown in FIGS. The same reference numerals as those shown in FIG.

  Further, the gap between the mounting table 2 and the top plate member 22 is not limited to that formed between the upper surface of the mounting table 2 and the lower end portion of the top plate member 22 described with reference to FIG. For example, as shown in FIG. 16, the processing table 20 is formed by fitting the mounting table 2 in which the mounting region of the wafer W protrudes upward into the recess of the top plate member 22. Various gases in the processing space 20 may be exhausted through a gap formed between the wall surface and the mounting table 2.

  Further, the exhaust opening for exhausting the reaction gas or the like in the processing space 20 to the exhaust space 10 is not limited to the gap between the mounting table 2 and the top plate member 22 as in the film forming apparatus described above. For example, as shown in FIGS. 17A and 17B, the top plate member 22 is formed in a flat cylindrical shape with the bottom surface opened, and for example, an opening 223 is provided in a side peripheral wall portion of the top plate member 22. The reaction gas or the like in the processing space 20 may be exhausted to the exhaust space 10 through the opening 223. Further, as shown in FIGS. 18A and 18B, an opening 27 is provided around the mounting area on which the wafer W of the mounting table is mounted, and a reactive gas or the like is supplied from here to the exhaust space 10. You may make it exhaust.

Here, the reaction gas is not limited to two types. For example, when forming a film of strontium titanate (SrTiO ₃ ), three kinds of reaction gases, for example, Sr (THD) ₂ (strontium bistetramethylheptanedionate) as a Sr raw material and Ti (OiPr) as a Ti raw material are used. ) ₂ (THD) ₂ (titanium bisisopropoxide bistetramethylheptanedionate) and ozone gas that is an oxidizing gas of these, the film forming apparatus can be applied to a process of forming a film by ALD. it can. In this case, of the three types of reaction gases supplied by switching to the processing space 20, one side of the two source gases to be subsequently supplied is the first reaction gas, and the other side is the second reaction gas. Think about it. That is, when the reaction gas is supplied in the order of Sr (THD) ₂ gas → Ti (OiPr) ₂ (THD) ₂ gas → ozone gas (the supply of purge gas is omitted), Sr (THD) ₂ gas And Ti (OiPr) ₂ (THD) ₂ gas, the former is the first reactive gas, the latter is the second reactive gas, and the relationship between Ti (OiPr) ₂ (THD) ₂ gas and ozone gas The former is the first reactive gas and the latter is the second reactive gas. In the relationship between ozone gas and Sr (THD) ₂ gas, the former may be considered as the first reactive gas and the latter as the second reactive gas. The same applies to the case where a film is formed using four or more kinds of reaction gases.

  Further, the processing space 20 of the wafer W is formed by vertically placing the mounting table 2 and the top plate member 22 provided with the concave portion, and the pressure of the processing space 20 is changed by changing the width of the gap between these members 2 and 22. In addition, the above-described film forming apparatus for adjusting the residence time of the reaction gas in the processing space 20 is not limited to the case where a so-called ALD process is applied. For example, even when this film forming apparatus is applied to a CVD (Chemical Vapor Deposition) process in which a reactive gas is continuously supplied into the processing space 20 to form a film on the surface of the wafer W, the consumption amount of the reactive gas The effect of suppressing the can be obtained.

  In addition, the processing space 20 is formed by making the mounting table 2 as the lower member face the top plate member 22 as the upper member in the vacuum container 1, and for example, by allowing the mounting table 2 to move up and down, The film forming apparatus having a configuration in which the width of the gap between the mounting table 2 forming the opening and the top plate member 22 can be adjusted includes a plurality of sets of the mounting table 2 and the top plate member 22 in the vacuum container 1. It is not limited to the case where the gap is adjusted to the same width. For example, as shown in FIG. 19, a film forming apparatus including only one set of the mounting table 2 and the top plate member 22 in the vacuum container 1 is also included in the technical scope of the present invention. Further, in the film forming apparatus provided with a plurality of these sets in the vacuum vessel 1, for example, as shown in FIG. 20, each mounting table 2 can be moved up and down independently, and the top plate member 22 in each processing space 20. You may enable it to vary the width | variety of the clearance gap between. In this case, for example, films having different film qualities can be formed by changing the width of the gap for each processing space 20 and adjusting the residence time and pressure of various reaction gases, for example. Further, for example, when different types of reaction gas are supplied to each processing space 20 to form different types of films, the mounting table 2 is moved up and down so that the gap has a width suitable for each type of reaction gas. May be.

  As a configuration of the manifold unit 3, gas may be supplied to the processing spaces 20 arranged in a horizontal row as shown in FIGS. Shows an example of such a manifold portion 3. The gas diffusion chambers 33 of the manifold portion 3 are formed so as to extend in the arrangement direction of the processing spaces 20 corresponding to the arrangement of the processing spaces 20.

  By the way, the atmosphere of each processing space 20 to which gas is supplied by the manifold unit 3 may be partitioned airtightly. That is, the manifold unit 3 may be configured to supply gas into each of the plurality of vacuum vessels. In each of the above examples, the manifold unit 3 is provided in the film forming apparatus. For example, the manifold unit 3 is provided in a gas processing apparatus that performs gas processing in a vacuum atmosphere, such as ashing, etching, oxidation processing, and nitriding processing equipment. A gas corresponding to the process may be supplied. The substrate to be processed by the above-described film forming apparatus is not limited to the semiconductor wafer W, and other substrates such as an FPD (flat panel display) substrate typified by an LCD (liquid crystal display) substrate and a ceramic substrate. It may be.

  Next, the film forming apparatus of FIG. 1 installed in a factory in an atmospheric atmosphere will be described with reference to FIG. 22 showing its external configuration. In the film forming apparatus, the side wall portion 12 and the top plate 11 constituting the vacuum vessel 1 are supported by a support portion 8 on a flat floor surface 8C. Hereinafter, the film forming apparatus supported by the support unit 8 in this way is referred to as a film forming apparatus 80.

  The support unit 8 includes a support base 81, support legs 82, a lateral member 83, and a fixing member 84. A section 12a protrudes outward from the lower end of the side wall portion 12 constituting the vacuum container 1 in the circumferential direction, and the support base 81 is formed along the circumference of the vacuum container 1, and each section 12a. Supports the back side. The support base 81 is configured not to interfere with the bottom plate 14 when the bottom plate 14 of the vacuum vessel 1 is lowered as described later and separated from the side wall portion 12.

  Assuming that the opening direction of the transfer port 15 is the back side in the film forming apparatus 80, a plurality of support legs 82 are provided at intervals on the left and right edges of the support base 81 from the near side to the back side. The leg 82 extends downward. The lower ends of the support legs 82 formed on the left side and the right side when viewed from the vacuum container 1 are connected to each other by a horizontal member 83 that extends from the front side to the back side. A plurality of fixing members 84 for fixing the support legs 82 and the lateral members 83 to the floor surface 8C are provided below the floor 8C at intervals.

  The support legs 82 provided on the left and right sides of the back side extend so as to extend to the upper side of the support base 81, and the extended portion constitutes a support column 85, and the support column 85 includes a support plate 86 and an upper plate 87. It supports in this order from the bottom. On the support plate 86, for example, devices such as a power supply unit of the film forming apparatus are arranged. Although not shown, the outer periphery of the film forming apparatus 80 is surrounded by a detachable side plate, which prevents the particles from entering the film forming apparatus 80 together with the upper plate 87.

A holding portion 91 that holds the back surface of the bottom plate 14 of the vacuum vessel 1 is provided in the lower space 8 </ b> A of the vacuum vessel 1 surrounded by the support legs 82 and the lateral members 83.
23A shows the lower side of the bottom plate 14, and FIG. 23B shows the upper side of the holding portion 91, respectively. As shown in FIG. 23B, the holding portion 91 includes an opening 92 and is formed in a cylindrical shape so as to surround the sleeve 25 and the driving portion 51. An annular protrusion 93 is formed at the upper end of the holding portion 91 along the circumferential direction of the holding portion 91, and the sleeve 25 protruding downward from the center portion of the bottom plate 14 and the drive are provided on the lower side of the bottom plate 14. A groove 94 corresponding to the shape of the protrusion 93 is formed so as to surround the portion 51. The protrusion 93 and the groove 94 are fitted to each other, and the holding portion 91 is positioned with respect to the bottom plate 14.

  A lifting mechanism 95 is provided below the holding portion 91. The elevating mechanism 95 includes, for example, a hydraulic cylinder for elevating the holding portion 91 vertically. The elevating mechanism 95 is provided with the bottom plate 14 of the vacuum vessel 1 along with the raising and lowering of the holding portion 91, and the bottom plate 14 via the support 24. The mounting table 2 moves up and down. Also, below the elevating mechanism 95, a cart 97 including a caster 96 that is a rolling element is provided. The lift mechanism 95 can move on the floor surface 8 </ b> C by the carriage part 97 that is a moving body, and the holding part 91 also moves on the floor surface 8 </ b> C as the lift mechanism 95 moves. That is, the lifting mechanism 95, the holding portion 91, and the bottom plate 14 are configured to be able to move on the floor surface 8C while being aligned with each other.

  Further, an exhaust pipe 62 connected to the bottom plate 14 of the vacuum vessel 1 is routed in the lower space 8A. In the figure, 62a is a joint that connects the upstream side and the downstream side of the exhaust pipe 62. On the front side of the lower space 8A, there is disposed a step 8B for a user of the apparatus to operate and operate each part of the apparatus.

  Next, a procedure for performing maintenance by opening the vacuum container 1 of the film forming apparatus 80 described above will be described. After the gas supply to the processing space 20 and the exhaust from the processing space 20 are stopped and the film forming process is stopped, the step 8B is moved from the front of the lower space 8A to, for example, either the left or right side, thereby lowering the lower space 8A. Open the front side of. Then, the upstream side of the exhaust pipe 62 connected to the joint 62a is removed from the joint 62a. Then, the downstream side of the exhaust pipe 62 connected to the joint 62a and the joint 62a is moved to an appropriate position so as not to interfere with the upstream side of the exhaust pipe 62 descending together with the bottom plate 14 when the bottom plate 14 is lowered. deep.

  Then, after removing a fastener (not shown) such as a screw connecting the bottom plate 14 and the side wall portion 12, the bottom plate 14 of the vacuum vessel 1 is lowered by the lifting mechanism 95 via the holding portion 91 as shown in FIG. The mounting table 2 connected to the bottom plate 14 is positioned such that the height of the upper surface is lower than the lower end of the support table 81 that supports the side wall portion 12. Thereafter, as shown in FIG. 25, the lifting mechanism 95 and the holding portion 91 are pulled out to the near side of the lower space 8 </ b> A of the vacuum container 1 by using the cart portion 97, and the lifting mechanism 95 and the support portion 91 are moved. The upstream side of the bottom plate 14, the mounting table 2, the support arm 23, the support column 24, and the exhaust pipe 62 is drawn out from the lower space 8A.

  Then, the user manually cleans the bottom plate 14 taken out from the lower space 8A and the members associated therewith, or disassembles each part taken out and cleans it with a predetermined cleaning device, and deposits due to the reaction gas. Remove. Further, when the bottom plate 14 is detached from the vacuum vessel 1 in this way, the lower side of the vacuum vessel 1 is opened to the lower space 8A as shown in FIG. A user manually wipes and cleans each part in the vacuum container 1 from the lower side of the opened vacuum container 1 through the lower space 8A or removes each part and cleans it with a cleaning device to remove the deposits. . In addition to performing such cleaning, the user performs various maintenance operations such as replacing defective parts.

  After the maintenance is completed, the bottom plate 14 is attached to the lower part of the vacuum vessel 1 in the reverse procedure of taking out the bottom plate 14 from the vacuum vessel 1 as described above, and the film forming apparatus 80 is returned to the state before starting the maintenance. .

  In addition, the vacuum vessel 1 of this film-forming apparatus can remove the top plate 11 from the side wall 12 and open | release the upper side of the said vacuum vessel 1 like the conventional film-forming apparatus. The top plate 11 is provided with a lid member 11 a that can be removed from the top plate 11 at a position corresponding to each processing space 20. The lower side of the lid member 11a is connected to a top plate member 22 that forms the processing space 20, and the top plate member 22 can be pulled out of the vacuum vessel 1 together with the lid member 11a. Then, by removing the lid member 11a and the top plate member 22, the mounting table 2 can be exposed, and the inside of the vacuum vessel 1 can be cleaned as described above for maintenance. Thus, when removing the top plate 11 and the lid member 11a, it is necessary to remove the liquid raw material and the reaction gas from each supply pipe and to remove each gas supply pipe 34 from the top plate 11. For example, when the top plate 11 and the lid member 11a are removed for maintenance as described above, the product may not be sufficiently removed by hand wiping from below, or the member may be replaced.

  According to the film forming apparatus 80 which is an embodiment of the vacuum processing apparatus, the mounting apparatus 2 is provided which is detachably provided on the top plate 11 and the side wall portion 12 of the vacuum vessel 1 and on which the wafer W is mounted. The side wall 12 is provided with the bottom plate 14 of the vacuum vessel 1, a lifting mechanism 95 that lifts and lowers the bottom plate 14, and a carriage 97 that is mounted with the lifting mechanism 95 and is movable along the floor surface 8 </ b> C. Then, the bottom plate 14 and the mounting table 2 can be removed and moved to positions where maintenance of the side wall portion 12, the bottom plate 14 and the mounting table 2 can be performed. Therefore, since it is not necessary to remove the top plate 11 from the vacuum vessel 1, it is not necessary to remove these liquid source and reaction gas from the supply pipes for supplying the liquid source and reaction gas to the manifold portion 3 by this removal. As a result, the maintenance work of the apparatus can be easily performed.

  By the way, as described above, a plurality of units including the holding portion 91, the elevating mechanism 95, the mounting table 2, and the bottom plate 14 that are moved into the outside of the lower space 8A are prepared. The film forming process is performed by attaching to the vacuum container 1, and one unit is attached to the vacuum container 1 and performing the film forming process during maintenance of other units, thereby reducing the operating rate of the apparatus in the maintenance of the unit. It may be suppressed.

  Next, the configuration of a semiconductor manufacturing apparatus 100A including, for example, four film forming apparatuses 80 will be described with reference to FIG. The semiconductor manufacturing apparatus 100A includes a first transfer chamber 102 that constitutes a loader module that loads and unloads wafers W, load lock chambers 103a and 103b, a second transfer chamber 104 that is a vacuum transfer chamber module, It has. A load port 105 on which the carrier C is placed is provided in front of the first transfer chamber 102, and the carrier C placed on the load port 105 is placed on the front wall of the first transfer chamber 102. A gate door GT that is connected and opened and closed together with the lid of the carrier C is provided. The above-described film forming apparatus 80 is airtightly connected to the second transfer chamber 104.

  An alignment chamber 106 for adjusting the orientation and eccentricity of the wafer W is provided on the side surface of the first transfer chamber 102. Each of the load lock chambers 103a and 103b is provided with a vacuum pump and a leak valve (not shown) so as to be switched between an air atmosphere and a vacuum atmosphere. That is, since the atmospheres of the first transfer chamber 102 and the second transfer chamber 104 are maintained in an air atmosphere and a vacuum atmosphere, respectively, the load lock chambers 103a and 103b transfer the wafer W between the transfer chambers. When adjusting the atmosphere. In the figure, G denotes between the load lock chambers 103a and 103b and the first transfer chamber 102 or the second transfer chamber 104, or between the second transfer chamber 104 and the transfer port 15 of the film forming apparatus 80. It is a gate valve (partition valve) which partitions off.

  The first transfer chamber 102 and the second transfer chamber 104 are provided with a first transfer means 107 and second transfer means 108a and 108b, respectively. The first transfer means 107 is a transfer arm for transferring the wafer W between the carrier C and the load lock chambers 103 a and 103 b and between the first transfer chamber 102 and the alignment chamber 106. The second transfer means 108a and 108b are transfer arms for transferring the wafer W between the load lock chambers 103a and 103b and the film forming apparatus.

  The carrier C is transferred to the semiconductor manufacturing apparatus 100 </ b> A, placed on the load port 105, and connected to the first transfer chamber 102. Next, the gate door GT and the lid of the carrier C are simultaneously opened, and the wafer W in the carrier C is loaded into the first transfer chamber 102 by the first transfer means 107, and then transferred to the alignment chamber 106, and the orientation thereof. After the adjustment of the eccentricity is carried out, it is transferred to the load lock chamber 103a (or 103b). After the pressure in the load lock chamber 103a (or 103b) is adjusted, the wafer W is loaded into the second transfer chamber 104 from the load lock chamber 103 by the second transfer means 108a or the transfer means 108b. Subsequently, the gate valve G of the film forming apparatus 80 is opened, and the second transfer means 108a (or 108b) transfers the wafer W to the film forming apparatus 80.

  When the above-described film forming process is completed by the film forming apparatus 80, the gate valve G of the film forming apparatus 80 is opened, and the second transfer means 108a (108b) enters the vacuum container 1 of the film forming apparatus 80. . The wafer W processed in the above-described operation is transferred to the second transfer means 108a (108b), and then the second transfer means 108a (108b) is loaded in the load lock chamber 103a (or 103b). Then, the wafer W is delivered to the first transfer means 107. Then, the first transfer means 107 returns the wafer W to the carrier C.

It is a longitudinal cross-sectional view of the film-forming apparatus which concerns on embodiment. It is a perspective view which shows schematic structure inside the said film-forming apparatus. It is a cross-sectional top view of the said film-forming apparatus. It is a longitudinal cross-sectional view which shows the process area | region in the said film-forming apparatus. It is a bottom view which shows the top-plate member which comprises the said process area | region. It is a longitudinal cross-sectional view of an injector. It is a gas supply path | route figure of the said film-forming apparatus. It is a 1st operation | movement figure of the said film-forming apparatus. It is a 2nd operation | movement figure of the said film-forming apparatus. It is a gas supply sequence figure of the film-forming process by the said film-forming apparatus. It is explanatory drawing which showed a mode that gas went to a process space from a manifold part. It is a 3rd operation | movement figure of the said film-forming apparatus. It is explanatory drawing which concerns on the effect | action of the said film-forming apparatus. It is the cross-sectional top view and vertical side view which show the modification of the said film-forming apparatus. It is a vertical side view which shows the other modification of the said film-forming apparatus. It is a vertical side view which shows the other example of a mounting base and a top-plate member. It is explanatory drawing which shows the other example of a top-plate member. It is explanatory drawing which shows the further another example of a mounting base. 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 explanatory drawing which shows another example of a manifold part. It is an external appearance perspective view of the said film-forming apparatus supported by the support part. It is the lower surface side perspective view of a bottom plate, and the upper surface side perspective view of a holding | maintenance part. It is the effect | action figure which showed the downward movement of the bottom plate of the vacuum vessel of the said film-forming apparatus. It is the perspective view which showed the mounting base and bottom plate withdraw | derived from the downward space of the vacuum vessel. It is a lower perspective view of the vacuum vessel with the bottom plate removed. A vacuum processing apparatus including the film forming apparatus.

Explanation of symbols

W Wafer 1 Vacuum container 10 Exhaust space 14 Bottom plate 100 Control unit 2 Mounting table 20 Processing space 21 Stage heater 22 Top plate member 23 Support arm 24 Support column 3 Manifold unit 4 Injector 64 Vacuum pump 7 Gas supply control unit 71 Source gas supply source 72 Oxygen gas supply source 73 Purge gas supply sources 721 and 731
Pressure regulating valves 712, 722, 732
On-off valve

Claims (9)

In a vacuum processing apparatus that performs processing on a substrate using a processing gas in a vacuum vessel,
A plurality of lower members provided in the vacuum container, each including a substrate placement region;
A plurality of upper members that are provided to face each of these lower members, and that form a processing space between the substrate placement region,
An exhaust opening formed along the circumferential direction of the processing space, for communicating the inside of the processing space and the atmosphere in the vacuum vessel outside the processing space;
A processing gas supply mechanism common to a plurality of processing spaces formed by the set of the upper member and the lower member;
A plurality of branch paths for branching from the processing gas supply mechanism via a common gas supply path, and supplying a processing gas to each of the plurality of processing spaces;
A diffusion chamber provided at a downstream end of the common gas supply path, having a cross-sectional area larger than a cross-sectional area of the gas supply path, and having the plurality of branch paths connected to the downstream side;
Evacuation means for evacuating the processing space through the exhaust opening and the atmosphere in the vacuum vessel;
A vacuum processing apparatus comprising: The exhaust opening is vacuum processing instrumentation apparatus according to claim 1, characterized in that it is constituted by a gap formed in the circumferential direction between the lower edge and the lower member of the upper member. It said plurality of pairs of the upper member and the lower member, the vacuum processing apparatus according to claim 1, wherein that it is arranged along the circumferential direction of the vacuum vessel. The diffusion chamber vacuum processing apparatus according to any one of claims 1 to 3, characterized in that provided directly on the vacuum vessel. The common gas supply path is erected and connected to the center of the upper surface of the diffusion chamber, and the processing gas supply mechanism is a nozzle for vaporizing a liquid material into the erected common gas supply path and discharging the processing gas. The vacuum processing apparatus according to any one of claims 1 to 4 , further comprising: The vacuum processing apparatus according to claim 5 , wherein a length of a supply path of the liquid source connecting the storage unit for storing the liquid source and the nozzle is 2 m or less. The vacuum according to claim 5 or 6 , wherein a supply path for supplying a processing gas other than the processing gas obtained by vaporizing the liquid raw material is connected to the standing common gas supply path. Processing equipment. The processing gas supply mechanism includes a mechanism for supplying a first reaction gas and a mechanism for supplying a second reaction gas that reacts with the first reaction gas to generate a reaction product on the substrate. And a mechanism for supplying a purge gas,
The process gas supply mechanism is controlled so that a purge gas is supplied between the timings of supplying the reaction gas by executing the cycle of supplying the first reaction gas and the second reaction gas alternately to the processing space many times. the vacuum processing apparatus according to any one of claims 1 to 7, characterized in that a control unit for. The inner peripheral surface of the upper member is formed in a shape that widens toward the bottom from the top, and a gas supply port for supplying a processing gas is formed in the center of the upper member. Item 9. The vacuum processing apparatus according to any one of Items 1 to 8 .

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