JP6807275B2 - Film formation method and film deposition equipment - Google Patents

Description

The present invention relates to a film forming method and a film forming apparatus for forming a predetermined film on an object to be processed such as a semiconductor wafer.

Conventionally, in the manufacture of semiconductor devices, a batch type vertical film forming apparatus has been known as a film forming apparatus capable of performing a film forming process on a semiconductor wafer (hereinafter, also simply referred to as a wafer) with high throughput. There is.

As a batch-type vertical film-forming device that enables more uniform film formation as the dimensions of semiconductor devices become smaller and the diameter of wafers increases, each wafer is supported in the holding area of the substrate in the processing container. A gas injector (gas dispersion nozzle) having a plurality of gas discharge holes is vertically arranged at the position, and an exhaust port is provided at a position facing the gas injector, and the processing gas is discharged from each gas discharge hole along the surface of each wafer. A side-flow type or cross-flow type film forming apparatus that supplies and forms a uniform gas flow is used (for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2011-135044

By the way, semiconductor devices are becoming finer and more complicated, and even with the technique described in Patent Document 1, the uniformity of the film is becoming insufficient. In particular, in a so-called pattern wafer in which a pattern is formed, even if the concentration of the film-forming raw material gas on the wafer is uniform, the film-forming raw material gas is consumed before reaching the center of the wafer and is consumed in the center of the wafer. The microloading effect of thinning the film becomes a problem.

This means that even if the concentration of the film-forming raw material gas on the semiconductor wafer is uniform, a uniform film cannot be formed. That is, in order to form a uniform film, it is necessary to control the concentration distribution of the film-forming raw material gas on the wafer.

Therefore, a technique for controlling the film thickness by controlling the concentration distribution of the film-forming raw material gas by using the side-flow method or cross-flow type batch-type vertical film forming apparatus described in Patent Document 1 is desired. ..

However, since the flow system of the film-forming raw material gas of gas injector → wafer → exhaust port formed by the side-flow method or cross-flow type batch type vertical film forming apparatus is formed, it is moved to the exhaust port side. The more the film-forming raw material gas reacts, the higher the number of reactive species formed. Since such a tendency is closely related to the physical characteristics of the film-forming raw material gas, it is necessary to drastically change the process conditions and the apparatus configuration in order to manipulate the concentration distribution of the reactive species. In addition, it is difficult to reduce the concentration in the region where the concentration of the reactive species has increased once the decomposition has progressed, so it is difficult to control the concentration distribution of the reactive species by controlling the distribution of the film-forming raw material gas. is there.

Therefore, the present invention provides a film forming technique capable of controlling the concentration distribution of reactive species on an object to be treated by using a side flow type or cross flow type batch type vertical film forming apparatus. Is the subject.

To solve the above problems, a first aspect of the present invention, the vacuum can be held processing chamber, the object to be processed in several place in multiple stages, a predetermined position on the side of said plurality of workpiece A film-forming raw material gas is supplied along the surface of a plurality of objects to be processed from a film-forming raw material gas supply unit provided in collectively to a film forming method for forming a predetermined film, the predetermined gas for adjusting the concentration of the concentration control gas supply portion provided in a position different from the position before Symbol plurality of the processed By supplying the film-forming raw material gas on the surface of the body to a portion having a high concentration distribution and moving the portion having a high concentration distribution in the supply direction of the concentration adjusting gas, the said film-forming raw material gas on the plurality of objects to be treated. Provided is a film forming method characterized by controlling the concentration distribution of reactive species.
A second aspect of the present invention is to arrange a plurality of objects to be processed in multiple stages in a processing container capable of holding a vacuum, and to provide a film-forming raw material gas at a predetermined position on the side of the plurality of objects to be processed. A film-forming raw material gas is supplied from the supply unit along the surfaces of a plurality of objects to be processed, and a predetermined film is collectively applied to the plurality of objects to be processed by the reactive species generated from the film-forming raw material gas on the object to be processed. It is a film forming method for forming a film, in which a plurality of concentration adjusting gas supply units are provided at a position different from the predetermined position and around the processing container, and a film forming raw material on the surface of the plurality of objects to be processed. The supply and stop of the concentration adjusting gas from the plurality of concentration adjusting gas dispersion nozzles and the supply amount from each concentration adjusting gas dispersion nozzle are controlled according to the gas concentration distribution, and the plurality of objects to be treated are controlled. Provided is a film forming method characterized in that a portion having a high concentration distribution of a film-forming raw material gas on the surface of a body is moved to control the concentration distribution of the reactive species on the plurality of objects to be treated.

A third aspect of the present invention is a film forming apparatus that collectively forms a predetermined film on a plurality of objects to be processed, and can hold a vacuum in which the plurality of objects to be processed are accommodated and arranged in multiple stages. A film-forming raw material gas supply unit provided at a predetermined position on the side of the plurality of objects to be processed and supplying the film-forming raw material gas along the surface of the object to be processed, and the predetermined positions. From the concentration-adjusting gas supply unit, the film-forming raw material gas supply unit, and the concentration-adjusting gas supply unit, which are provided at different positions from the above and supply the concentration-adjusting gas to the surfaces of the plurality of objects to be processed. A control unit for controlling the supply of the film-forming raw material gas and the concentration adjusting gas is provided, and the control unit forms a film on the surface of the object to be processed in the processing container from the film-forming raw material gas supply unit. The raw material gas is supplied, and the concentration adjusting gas is supplied from the concentration adjusting gas supply unit to a portion of the surface of the plurality of objects to be treated where the concentration distribution of the film-forming raw material gas is high. A film formation characterized by controlling the concentration distribution of reactive species generated from the raw material gas formed on the plurality of objects to be treated by moving the high portion in the supply direction of the concentration adjusting gas. Provide the device.
A fourth aspect of the present invention is a film forming apparatus that collectively forms a predetermined film on a plurality of objects to be processed, and can hold a vacuum in which the plurality of objects to be processed are accommodated and arranged in multiple stages. A processing container, a film-forming raw material gas supply unit provided at a predetermined position on the side of the plurality of objects to be processed, and supplying the film-forming raw material gas along the surface of the object to be processed, and the predetermined positions. A plurality of concentration adjusting gas supply units provided at different positions from the above and around the processing container to supply the concentration adjusting gas to the surfaces of the plurality of objects to be processed, and the film-forming raw material gas supply unit. A control unit for controlling the supply of the film-forming raw material gas and the concentration-adjusting gas from the concentration-adjusting gas supply unit is provided, and the control unit is provided in the processing container from the film-forming raw material gas supply unit. The concentration of the film-forming raw material gas is supplied to the surface of the object to be treated, and the concentration from the plurality of concentration adjusting gas dispersion nozzles is adjusted according to the concentration distribution of the film-forming raw material gas on the surface of the plurality of objects to be treated. By controlling the supply and stop of the adjusting gas and the supply amount from each concentration adjusting gas dispersion nozzle, the portion of the surface of the plurality of objects to be treated having a high concentration distribution of the film-forming raw material gas is moved, and the plurality of components is moved. Provided is a film forming apparatus characterized by controlling the concentration distribution of the reactive active species on the object to be treated.

A fifth aspect of the present invention is a storage medium that operates on a computer and stores a program for controlling a film forming apparatus, and the program is the first aspect or the second aspect at the time of execution . Provided is a storage medium characterized in that a computer controls the film forming apparatus so that the film forming method from the above viewpoint is performed.

According to the present invention, by supplying the concentration adjusting gas to the surface of the object to be processed from a position different from the position where the film-forming raw material gas is supplied, the reaction activity generated from the film-forming raw material gas on the object to be processed The concentration distribution of the species can be controlled.

It is a vertical sectional view which shows the basic structure of the film forming apparatus for carrying out the film forming method of this invention. It is a horizontal sectional view which shows the basic structure of the film-forming apparatus for carrying out the film-forming method of this invention. It is a figure for demonstrating the concentration distribution of SiCl ₂ , which is a reactive species at the time of depositing Si using HCD gas by the film forming apparatus shown in FIGS. 1 and 2. It is a horizontal sectional view which shows the film forming apparatus which concerns on 1st example of 1st Embodiment of this invention. It is a horizontal sectional view which shows the film forming apparatus which concerns on 2nd example of 1st Embodiment of this invention. It is a horizontal sectional view which shows the film forming apparatus which concerns on 3rd example of 1st Embodiment of this invention. It is a horizontal sectional view which shows the film forming apparatus which concerns on 2nd Embodiment of this invention. It is a figure which shows the simulation result in the film forming apparatus of a basic structure. It is a figure which shows the simulation result in 1st example of 1st Embodiment. It is a figure which shows the simulation result in the 2nd example of 1st Embodiment. It is a figure which shows the simulation result in the 3rd example of 1st Embodiment. It is a figure which shows the simulation result in the film forming apparatus of a basic structure. It is a figure which shows the 1st simulation result in 2nd Embodiment. It is a figure which shows the 2nd simulation result in 2nd Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, components having substantially the same function and configuration are designated by the same reference numerals, and duplicate description will be omitted.

<Basic configuration of film forming equipment>
FIG. 1 is a vertical sectional view showing a basic configuration of a film forming apparatus for carrying out the film forming method of the present invention, and FIG. 2 is a horizontal sectional view of the film forming apparatus shown in FIG.

Here, an example is a film forming apparatus in which hexachlorodisilane (HCD; Si ₂ Cl ₆ ) is used as a silicon raw material and a SiO ₂ film is formed by an atomic layer deposition method (ALD) in which HCD gas and an oxidizing agent are alternately supplied. explain.

The film forming apparatus 100 of this example has the same configuration as the cross-flow type batch type vertical film forming apparatus. The film forming apparatus 100 has a cylindrical processing container 1 with a ceiling whose lower end is opened. The entire processing container 1 is formed of, for example, quartz, and a quartz ceiling plate 2 is provided in the vicinity of the upper end portion of the processing container 1 to seal the lower region thereof. Further, a metal manifold 3 formed in a cylindrical shape is connected to the lower end opening of the processing container 1 via a seal member 4 such as an O-ring.

The manifold 3 supports the lower end of the processing container 1, and a quartz wafer on which a plurality of semiconductor wafers (silicon wafers) W, for example, 50 to 150 wafers (silicon wafers) W, are placed in multiple stages as an object to be processed from below the manifold 3. The boat 5 is inserted into the processing container 1. The wafer boat 5 has three rods 6 (see FIG. 2), and a plurality of wafers W are supported by grooves (not shown) formed in the rods 6.

The wafer boat 5 is placed on a table 8 via a quartz heat insulating cylinder 7, and the table 8 penetrates a metal (stainless steel) lid 9 that opens and closes the lower end opening of the manifold 3. It is supported on the rotating shaft 10.

A magnetic fluid seal 11 is provided at the penetrating portion of the rotating shaft 10, and the rotating shaft 10 is airtightly sealed and rotatably supported. Further, a sealing member 12 for maintaining the sealing property in the processing container 1 is interposed between the peripheral portion of the lid portion 9 and the lower end portion of the manifold 3.

The rotating shaft 10 is attached to the tip of an arm 13 supported by, for example, an elevating mechanism (not shown) of a boat elevator or the like, and integrally elevates the wafer boat 5 and the lid 9 or the like in the processing container 1. Is inserted and removed. The table 8 may be fixedly provided on the lid 9 side so that the wafer W can be processed without rotating the wafer boat 5.

Further, the film forming apparatus 100 supplies a deposition material gas supply mechanism 14 for supplying the HCD gas as the film forming raw material gas, the inert gas used as a purge gas, for example, N ₂ gas, Ar gas or the like into the processing container 1 It has an inert gas supply mechanism 15 and an oxidant supply mechanism 16 that supplies an oxidizing agent, for example, a mixed gas of O ₂ gas and H ₂ gas, O ₂ gas, O ₃ gas, and the like.

The film-forming raw material gas supply mechanism 14 is connected to the film-forming raw material gas supply source 18, the gas pipe 19 that guides the film-forming raw material gas from the film-forming raw material gas supply source 18, and the gas pipe 19 into the processing container 1. It has a gas dispersion nozzle 20 that guides the film-forming raw material gas.

The inert gas supply mechanism 15 includes an inert gas supply source 21, a gas pipe 22 for guiding the inert gas from the inert gas supply source 21, and a gas dispersion nozzle 23 for guiding the inert gas into the processing container 1. doing.

The oxidant supply mechanism 16 has an oxidant supply source 24, a gas pipe 25 for guiding the oxidant into the processing container, and a gas dispersion nozzle 26 for guiding the oxidant into the processing container 1.

The gas dispersion nozzles 20, 23 and 26 are made of quartz, penetrate the side wall of the manifold 3 inward, bend upward and extend vertically. For the plurality of gas discharge holes 20a, 23a and 26a (20a, 26a) in the vertical portions of the gas dispersion nozzles 20, 23 and 26, respectively, over the length in the vertical direction corresponding to the wafer support range of the wafer boat 5. (Shown only in FIG. 2) are formed at predetermined intervals corresponding to the intervals of the wafers W. As a result, gas can be discharged horizontally from the gas discharge holes 20a, 23a, and 26a toward the surface of each wafer W in the processing container 1 substantially uniformly.

The gas pipes 19, 22 and 25 are provided with on-off valves 19a, 22a and 25a and flow rate controllers 19b, 22b and 25b, respectively.

The processing container 1 is airtightly welded to the outer wall of the processing container 1 and includes a storage compartment wall 32 for accommodating the gas dispersion nozzles 20, 23 and 26. The containment compartment wall 32 is formed of, for example, quartz. The storage compartment wall 32 has a concave cross section and covers the opening 31 formed in the side wall of the processing container 1. The opening 31 is formed elongated in the vertical direction so as to cover all the semiconductor wafers W supported by the wafer boat 5 in the vertical direction. In the inner space defined by the storage compartment wall 32, the dispersion nozzle 20 for discharging the film-forming raw material gas, the dispersion nozzle 23 for discharging the inert gas, and the dispersion nozzle for discharging the oxidizing agent are in the inner space. 26 are arranged. The film-forming raw material gas discharged from the dispersion nozzle 20, the inert gas discharged from the dispersion nozzle 23, and the oxidizing agent discharged from the dispersion nozzle 26 are supplied to the inside of the processing container 1 through the opening 31.

In the embodiment, the gas dispersion nozzles 20, 23, and 26 are provided one by one at different positions in the storage compartment wall 32 described later, but two or more of them may be provided. Further, the inert gas pipe may be connected to the nozzle 20 to discharge the inert gas as a carrier gas together with the raw material gas. Further, the inert gas pipe may be connected to the nozzle 26 to discharge the inert gas as a carrier gas together with the oxidizing agent.

An exhaust port 37 for evacuating the inside of the processing container 1 is provided on the side wall portion of the processing container 1 facing the opening 31. The exhaust port 37 is vertically elongated so as to correspond to the wafer boat 5. An exhaust port cover member 38 having a U-shaped cross section is attached to a portion of the processing container 1 corresponding to the exhaust port 37 so as to cover the exhaust port 37. The exhaust port cover member 38 extends upward along the side wall of the processing container 1. An exhaust pipe 39 for exhausting the processing container 1 is connected to the lower part of the exhaust port cover member 38 via the exhaust port 37. An exhaust device 41 including a pressure control valve 40 for controlling the pressure in the processing container 1 and a vacuum pump is connected to the exhaust pipe 39, and the inside of the processing container 1 is exhausted by the exhaust device 41 via the exhaust pipe 39. Will be done. That is, the film forming apparatus 100 is a cross-flow system in which the film forming raw material gas, the inert gas, and the oxidizing agent discharged from the dispersion nozzles 20, 23, and 26 are exhausted from the exhaust port 37 through the surface of the wafer W. It is a film forming apparatus of.

Further, a tubular heating mechanism 42 for heating the processing container 1 and the wafer W inside the processing container 1 is provided so as to surround the outer periphery of the processing container 1.

The film forming apparatus 100 has a control unit 50. The control unit 50 controls each component of the film forming apparatus 100, for example, supply / stop of each gas by opening / closing valves 19a, 22a, 25a, controlling the gas flow rate by the flow rate controllers 19b, 22b, 25b, and the exhaust device 41. Exhaust control by the heating mechanism 42, control of the temperature of the wafer W by the heating mechanism 42, and the like. The control unit 50 has a CPU (computer), a main control unit that performs the above control, and an input device, an output device, a display device, and a storage device. A program for controlling the processing executed by the film forming apparatus 100, that is, a storage medium in which the processing recipe is stored is set in the storage device, and the main control unit sets a predetermined processing recipe stored in the storage medium. Is called, and the film forming apparatus 100 controls so that a predetermined process is performed based on the process recipe.

Next, the processing operation of the basic configuration of the film forming apparatus configured as described above will be described. The following processing operation is executed based on the processing recipe stored in the storage medium of the storage unit in the control unit 50.

First, for example, 50 to 150 semiconductor wafers W (pattern wafers) in which trenches, holes, wirings, etc. as described above are formed in a predetermined pattern are mounted on a wafer boat 5, and a quartz heat insulating cylinder is mounted on a turntable 8. The wafer boat 5 on which the wafer W is mounted is placed via the 7 and raised by an elevating mechanism (not shown) such as a boat elevator to carry the wafer boat 5 into the processing container 1 from the lower opening.

At this time, the inside of the processing container 1 is preheated by the tubular heating mechanism 42 so that the temperature inside the processing container 1 becomes a predetermined temperature within a range suitable for film formation. Then, while supplying an inert gas, the pressure inside the processing container 1 is adjusted to a predetermined range suitable for film formation, and then the valves 19a and 25a are intermittently opened and closed, and a Si deposition step using HCD gas and a Si deposition step are performed. Oxidation steps with an oxidizing agent are alternately supplied with a purge in the processing vessel 1 interposed therebetween, and a SiO ₂ film is formed by ALD.

Each gas flow rate during film formation is controlled to a predetermined flow rate by the flow rate controllers 19b, 22b, and 25d.

After the film formation is completed, the valve 19a and the valve 25a are closed to complete the film formation while continuing to supply the inert gas, and the inside of the processing container 1 is exhausted by the exhaust device 41 via the exhaust pipe 39 while being inert. The inside of the processing container 1 is purged with gas. Then, after returning the inside of the processing container 1 to normal pressure, the wafer boat 5 is lowered by an elevating mechanism (not shown) to carry the wafer boat 5 out of the processing container 1.

By the way, with the miniaturization of semiconductor devices, the surface area ratio of the wafer including the fine uneven pattern is increasing. Here, the surface area ratio refers to the surface area W1 of a wafer having a fine concavo-convex pattern formed (hereinafter, also referred to as a pattern wafer) in a wafer having the same diameter, and a semiconductor wafer having no concavo-convex pattern formed (hereinafter, also referred to as a bare wafer). ) Divided by the surface area W2 (W1 / W2).

When a predetermined film is formed on a batch type apparatus that collectively processes a plurality of wafers, the film is formed while rotating the semiconductor wafer for the purpose of uniformly forming the predetermined film on the wafer W. Although this method is used, in this method, the central portion of the semiconductor wafer is located farthest from the supply port of the film-forming raw material gas.

When such a pattern wafer is formed, the consumption rate of the film-forming raw material gas increases, so that the film thickness of the central portion farthest from the supply port of the film-forming raw material gas is the film thickness of the peripheral portion of the bare wafer. A microloading effect is produced, which is thinner than that. Then, it is known from the experiments of the inventors that the amount of decrease in the film thickness becomes a substantially unique value depending on the surface area ratio and the process conditions of the film formation.

That is, in order to uniformly form a predetermined film on the semiconductor wafer on which the uneven pattern is formed, the difference between the film thickness distribution when the bare wafer is formed and the film thickness distribution when the pattern wafer is formed. It is necessary to establish a process method that can control the film formation in consideration of the above.

The deposition of the film on the semiconductor wafer is caused by the concentration of the reactive species produced by the thermal decomposition of the film-forming raw material gas. Therefore, in order to control the film thickness distribution on the surface of the semiconductor wafer, it is necessary to establish a method capable of controlling the concentration distribution of the reactive species, that is, the film-forming raw material.

However, in the film forming apparatus 100 having the above basic configuration, the HCD gas, which is the film forming raw material gas, is discharged from the dispersion nozzle 20 together with the inert gas in the Si deposition step, flows along the surface of the wafer W, and flows from the exhaust port 37. Since it is a cross-flow method in which the gas is discharged, a flow of the film-forming raw material gas is formed in the order of gas injector → wafer → exhaust port, and the length of the film-forming raw material gas introduced into the furnace is 1 to 2 m until it passes through the wafer. Therefore, it is considered that the thermal decomposition of the gas is in progress at the wafer position. Therefore, inevitably, the HCD is decomposed by the reaction formula shown in the following (1) toward the exhaust port side to easily generate SiCl _2, which is a reaction active species, and as shown in the schematic diagram of FIG. A distribution is formed in which the concentration is high near the exhaust side.
Si ₂ Cl ₆ → SiCl ₂ + SiCl ₄ ... (1)

Since such a tendency is closely related to the physical characteristics of the film-forming gas in the processing vessel, it is necessary to drastically change the process conditions and the equipment configuration in order to manipulate the concentration distribution of the reactive species. .. In addition, it is difficult to reduce the concentration in the region where the concentration of the reactive species has increased once the decomposition has progressed, so it is difficult to control the concentration distribution of the reactive species by controlling the distribution of the film-forming raw material gas. is there. That is, with only the configuration of the film forming apparatus 100 having the above basic configuration, even if the SiCl ₂ concentration, that is, the HCD gas concentration distribution (peak position) is to be moved for film thickness control, the gas concentration distribution once formed can be changed. There wasn't.

<First Embodiment of an apparatus for carrying out the method according to the present invention>
Therefore, a film forming method capable of solving the above points was examined.
Hereinafter, the first embodiment of the apparatus for carrying out the method according to the present invention will be described.

As a result of examining a method for adjusting the concentration distribution of the film-forming raw material gas in the side-flow type or cross-flow type batch type vertical film forming apparatus, the present inventor supplies the film-forming raw material gas into the processing container 1. At that time, it was found that it is effective to discharge the concentration distribution adjusting gas to a desired position in the processing container 1.

Therefore, in the present embodiment, gas dispersion nozzles having the same structure as the gas dispersion nozzles 20, 23, and 26 are arranged at desired positions around the wafer W in the processing container 1, and the gas discharge of the gas dispersion nozzles is performed. A concentration adjusting gas is discharged from the holes to the surface of each wafer.

FIG. 4 is a horizontal sectional view showing a film forming apparatus according to the first example of the first embodiment. In the film forming apparatus 101 of this example, in addition to the components of the film forming apparatus 100 shown in FIGS. 1 and 2, recesses 70A and 70B formed in the vertical direction on both sides of the accommodating partition wall 32 around the processing container 1, respectively. And 60A and 60B for concentration adjusting gas dispersion nozzles provided in the recesses 70A and 70B, respectively. In the concentration adjusting gas dispersion nozzles 60A and 60B, a plurality of concentration adjusting gas discharge holes 60Aa and 60Ba correspond to the distance between the wafers W, respectively, over the length in the vertical direction corresponding to the wafer support range of the wafer boat 5. It is formed at predetermined intervals. As a result, the concentration adjusting gas can be discharged horizontally from each concentration adjusting gas discharge hole toward the surface of each wafer W in the processing container 1. The control unit 50 can also control the supply of the concentration adjusting gas (the same applies to the film forming apparatus of FIGS. 5 to 7).

The lower portions of the concentration adjusting gas dispersion nozzles 60A and 60B are bent in the horizontal direction and extend outward through the side wall of the manifold 3. One ends of the gas pipes 61A and 61B are connected to the ends of the concentration adjusting gas dispersion nozzles 60A and 60B, respectively, and the concentration adjusting gas supply sources 62A and 62B are connected to the other ends of the gas pipes 61A and 61B, respectively. Is connected. The gas pipes 61A and 61B are provided with on-off valves 61Aa and 61Ba, and flow rate controllers 61Ab and 61Bb, respectively.

FIG. 5 is a horizontal sectional view showing a film forming apparatus according to a second example of the first embodiment. In addition to the components of the film forming apparatus 100 shown in FIGS. 1 and 2, the film forming apparatus 102 of this example faces the intermediate position between the accommodation compartment wall 32 and the exhaust port 37 around the processing container 1, respectively. It has recesses 70C and 70D formed elongated in the vertical direction, and concentration adjusting gas dispersion nozzles 60C and 60D provided in the recesses 70C and 70D, respectively. In the concentration adjusting gas dispersion nozzles 60C and 60D, a plurality of concentration adjusting gas discharge holes 60Ca and 60Da correspond to the distance between the wafers W, respectively, over the length in the vertical direction corresponding to the wafer support range of the wafer boat 5. It is formed at predetermined intervals. As a result, the concentration adjusting gas can be discharged horizontally from each concentration adjusting gas discharge hole toward the surface of each wafer W in the processing container 1.

The lower portions of the concentration adjusting gas dispersion nozzles 60C and 60D are bent in the horizontal direction and extend outward through the side wall of the manifold 3. One ends of the gas pipes 61C and 61D are connected to the ends of the concentration adjusting gas dispersion nozzles 60C and 60D, respectively, and the concentration adjusting gas supply sources 62C and 62D are connected to the other ends of the gas pipes 61C and 61D, respectively. Is connected. The gas pipes 61C and 61D are provided with on-off valves 61Ca and 61Da, and flow rate controllers 61Cb and 61Db, respectively.

FIG. 6 is a horizontal sectional view showing a film forming apparatus according to a third example of the first embodiment. In addition to the components of the film forming apparatus 100 shown in FIGS. 1 and 2, the film forming apparatus 103 of this example includes recesses 70E formed in the vertical direction on both sides of the exhaust port cover member 38 around the processing container 1, respectively. It has a 70F and gas dispersion nozzles 60E and 60F for concentration adjustment provided in the recesses 70E and 70F, respectively. In the concentration adjusting gas dispersion nozzles 60E and 60F, a plurality of concentration adjusting gas discharge holes 60Ea and 60F correspond to the distance between the wafers W, respectively, over the length in the vertical direction corresponding to the wafer support range of the wafer boat 5. It is formed at predetermined intervals. As a result, the concentration adjusting gas can be discharged horizontally from each concentration adjusting gas discharge hole toward the surface of each wafer W in the processing container 1.

The lower portions of the concentration adjusting gas dispersion nozzles 60E and 60F are bent in the horizontal direction and extend outward through the side wall of the manifold 3. One ends of the gas pipes 61E and 61F are connected to the ends of the concentration adjusting gas dispersion nozzles 60E and 60F, respectively, and the concentration adjusting gas supply sources 62E and 62F are connected to the other ends of the gas pipes 61E and 61F, respectively. Is connected. The gas pipes 61E and 61F are provided with on-off valves 61Ea and 61Fa, and flow rate controllers 61Eb and 61Fb, respectively.

The concentration regulating gas, e.g. N ₂ gas can be suitably used an inert gas such as Ar gas.

In the first to third examples as described above, in the Si deposition step, the concentration adjusting gas is discharged from the discharge holes of the respective concentration adjusting gas dispersion nozzles, so that the film-forming raw material gas is discharged in the discharge direction. The part with high concentration distribution of HCD gas can be moved. In this case, the adjustment amount can be controlled by adjusting the flow rate of the concentration adjusting gas from each concentration adjusting gas dispersion nozzle.

According to the first embodiment, at the time of film formation, a concentration adjusting gas dispersion nozzle is arranged at a predetermined position, and a predetermined amount of the concentration adjusting gas is discharged from the concentration adjusting gas dispersion nozzle, whereby the processing container 1 The distribution of the film-forming raw material gas (distribution of reactive species) on the surface of the wafer W inside can be controlled.

As a result, it is possible to suppress the formation of a portion having a high concentration of the film-forming raw material gas in the vicinity of the exhaust port 37, and to increase the concentration of the film-forming raw material gas in the center of the wafer where the film thickness becomes thin due to the loading effect. It becomes possible. Therefore, in-plane non-uniformity of the deposited film thickness of the film-forming raw material can be suppressed.

Further, if a distribution having a high concentration of the film-forming raw material gas in the center of the wafer W can be formed, it is possible to make the deposited film thickness of the film-forming raw material uniform without rotating the wafer W.

In the first to third examples of the present embodiment, two concentration adjusting gas dispersion nozzles are arranged at predetermined positions, but the number and arrangement positions of the concentration adjusting gas dispersion nozzles are the above-mentioned first. The present invention is not limited to the third example, and may be appropriately set according to the distribution of the film-forming raw material gas.

<Second embodiment>
FIG. 7 is a horizontal cross-sectional view showing the film forming apparatus according to the second embodiment. In the film forming apparatus 104 of the present embodiment, in addition to the components of the film forming apparatus 100 shown in FIGS. 1 and 2, the concentration is adjusted around the processing container 1 in the first to third examples of the first embodiment. It has all the gas dispersion nozzles 60A to 60F. One ends of the gas pipes 61A to 61F are connected to the dispersion nozzles 60A to 60F, respectively, and the concentration adjusting gas supply sources 62A to 62F are connected to the other ends of the gas pipes 61A to 61F, respectively. The gas pipes 61A to 61F are provided with on-off valves 61Aa to 61F and flow rate controllers 61Ab to 61Fb, respectively.

In the present embodiment, the discharge and stop of the concentration adjusting gas from each concentration adjusting gas dispersion nozzle and the discharge flow rate are controlled according to the distribution of the film forming raw material gas (HCD gas) grasped in advance. The distribution of the film-forming raw material gas (distribution of reactive species) on the surface of the wafer W in the processing container 1 can be controlled to a desired distribution. In this case, the control is to discharge the concentration adjusting gas from each concentration adjusting gas dispersion nozzle so as to obtain a desired film forming raw material gas distribution based on the film forming raw material gas distribution grasped in advance by the control unit 50. It suffices to control the stop and the discharge flow rate.

As a result, it is possible to suppress the formation of a portion having a high concentration of the film-forming raw material gas in the vicinity of the exhaust port 37 with respect to various film-forming raw material gas distributions, and the wafer center where the film thickness becomes thin due to the loading effect. It is possible to more effectively achieve an increase in the concentration of the film-forming raw material gas in the portion. Therefore, the in-plane uniformity of the deposited film thickness of the film-forming raw material can be improved regardless of the distribution of the film-forming raw material gas.

Further, by controlling the flow rate of the concentration adjusting gas from each concentration adjusting gas dispersion nozzle, a distribution having a high concentration of the film-forming raw material gas in the center of the wafer W can be formed relatively easily, and the wafer W can be formed. It becomes easier to achieve uniform deposition film thickness of the film-forming raw material without rotating the film.

In the present embodiment, an example in which six concentration adjusting gas dispersion nozzles are provided around the processing container 1 is shown, but the number of concentration adjusting gas dispersion nozzles is not limited to this. Finer control can be performed by increasing the number of gas dispersion nozzles for concentration adjustment. However, it is preferable to set an appropriate number in consideration of equipment cost and the like.

<Simulation result>
Next, the simulation results will be described.
[Simulation results in a film forming apparatus with a basic configuration]
First, in a batch-type vertical film forming apparatus having a basic configuration as shown in FIGS. 1 and 2, processing when the discharge position and discharge amount of the film-forming raw material gas and the discharge position and discharge amount of the inert gas are changed. The concentration distribution of the film-forming raw material gas in the container 1 was simulated by thermo-fluid analysis.

In the simulation, the film thickness of the predetermined film formed on the semiconductor wafer is considered to be due to the concentration of the reactive species produced by the thermal decomposition of the film forming raw material gas, and the film forming raw material. The concentration distribution of reactive species was simulated, not the concentration distribution of gas.

In this simulation, the simulation is carried out assuming a Si deposition process by thermal decomposition of HCD (Si ₂ Cl ₆ )) gas when forming a SiO ₂ film with ALD.
The thermal decomposition of HCD is based on the reaction formula represented by the above-mentioned equation (1). In this simulation, SiCl ₂ after the thermal decomposition is assumed to be a reactive species that contributes to the formation of a silicon film. , SiCl ₂ concentration distribution was simulated.

The specific simulation conditions are shown below.
Film-forming raw material gas: HCD (hexachlorodisilane (Si ₂ Cl ₆ )) gas Inert gas: N ₂ gas Temperature inside the processing vessel: 600 ° C.
Pitch between semiconductor wafers W: xmm
Clearance between the inner surface of the processing container and the semiconductor wafer W: 3 x mm
Pressure in the processing container (near the exhaust port 37): 30 Pa (0.225 Torr)

FIG. 8 is a diagram showing a simulation result in this case. In FIG. 8, the gas supply unit and the exhaust port are opposite to those in FIG. The same applies to FIGS. 9 to 14 below.

In FIG. 8, the concentrations of SiCl ₂ when the HCD gas and the N ₂ gas are discharged from the dispersion nozzle 20 for the film-forming raw material gas and the dispersion nozzle 23 for the inert gas of FIG. 2 at the flow rates shown below, respectively. The result of simulating the distribution is shown. In the simulation result of FIG. 8, the concentration of SiCl ₂ is shown in gray scale, and the darker the color (closer to black), the higher the concentration.

Gas flow rate of HCD gas and N ₂ gas were as follows. In this simulation, it is assumed that both the HCD gas and the N ₂ gas as the carrier gas are discharged from the gas dispersion nozzle 20.
・ Gas dispersion nozzle 20:
HCD gas 300 sccm + N ₂ gas 1500 sccm
・ Gas dispersion nozzle 23:
N ₂ gas 1500 sccm

From the simulation results shown in FIG. 8, the concentration of SiCl ₂ increases as the HCD gas discharged from the gas dispersion nozzle 20 advances to the exhaust port 37, and the influence of the N ₂ gas discharged from the gas dispersion nozzle 23 increases. As for the concentration distribution of SiCl ₂ , it was found that the region having the highest concentration (hereinafter, also referred to as the high concentration region) appears on the gas dispersion nozzle 23 side and the exhaust port 37 side. In addition, the inventor described the film thickness distribution when the film was formed under the same conditions as the above simulation conditions without rotating the semiconductor wafer in the actual machine, and the concentration distribution of the reactive species obtained in the above simulation results. Are confirmed to be approximately the same.

[Simulation result in the film forming apparatus of the first embodiment]
Next, in addition to the gas dispersion nozzle 20 for discharging the film-forming raw material gas and the carrier gas and the gas dispersion nozzle 23 for discharging the inert gas for purging shown in FIG. 8, the first to third embodiments of the first embodiment. As shown in the example, the concentration distribution of SiCl ₂ when the concentration adjusting gas dispersion nozzle was arranged was simulated. The basic simulation conditions were the same as in the case of the above-mentioned "simulation in the film forming apparatus having the basic configuration", and the flow rates of the gas from the gas dispersion nozzles 20 and 23 were also the same.

9 to 11 are the simulation results. FIG. 9 corresponds to the first example, and is a case where the concentration adjusting gas dispersion nozzles 60A and 60B of FIG. 4 are provided. FIG. 10 corresponds to the second example, and is a case where the concentration adjusting gas dispersion nozzles 60C and 60D of FIG. 5 are provided. FIG. 11 corresponds to the third example, and is a case where the concentration adjusting gas dispersion nozzles 60E and 60F of FIG. 6 are provided. In these, the simulation was performed by changing the flow rate of the inert gas discharged from the concentration adjusting gas dispersion nozzle.

Specifically, FIGS. 9 In the simulation shown in 11, 3 below the gas flow rate of HCD gas discharged from the concentration adjusting gas distribution nozzle (film deposition material gas) and N ₂ gas (inert gas) It was street by street.

(Conditions of the first example)
・ Fig. 9 (a)
Gas dispersion nozzle for concentration adjustment 60A: N ₂ gas 1000sccm
Gas dispersion nozzle for concentration adjustment 60B: N ₂ gas 1000 sccm
・ Fig. 9 (b)
Gas dispersion nozzle for concentration adjustment 60A: N ₂ gas 1000sccm
Gas dispersion nozzle for concentration adjustment 60B: N ₂ gas 5000 sccm
・ Fig. 9 (C)
Gas dispersion nozzle for concentration adjustment 60A: N ₂ gas 1000sccm
Gas dispersion nozzle for concentration adjustment 60B: N ₂ gas 10000sccm

(Conditions of the second example)
・ Fig. 10 (a)
Gas dispersion nozzle for concentration adjustment 60C: N ₂ gas 1000sccm
Gas dispersion nozzle for concentration adjustment 60D: N ₂ gas 1000 sccm
・ FIG. 10 (b)
Gas dispersion nozzle for concentration adjustment 60C: N ₂ gas 1000sccm
Gas dispersion nozzle for concentration adjustment 60D: N ₂ gas 5000 sccm
・ FIG. 10 (c)
Gas dispersion nozzle for concentration adjustment 60C: N ₂ gas 1000sccm
Gas dispersion nozzle for concentration adjustment 60D: N ₂ gas 10000sccm

(Conditions of the third example)
・ Fig. 11 (a)
Gas dispersion nozzle for concentration adjustment 60E: N ₂ gas 1000 sccm
Gas dispersion nozzle for concentration adjustment 60F: N ₂ gas 1000 sccm
・ FIG. 11 (b)
Gas dispersion nozzle for concentration adjustment 60E: N ₂ gas 1000 sccm
Gas dispersion nozzle for concentration adjustment 60F: N ₂ gas 5000 sccm
・ FIG. 11 (c)
Gas dispersion nozzle for concentration adjustment 60E: N ₂ gas 1000 sccm
Gas dispersion nozzle for concentration adjustment 60F: N ₂ gas 10000sccm

(Simulation result of the first example)
First, the simulation result of the first example shown in FIG. 9 will be described. In the simulation of the first example, in addition to the gas dispersion nozzles 20 and 23, the concentration adjusting gas dispersion nozzle 60A is arranged at the upper position of the gas dispersion nozzle 23, and the concentration adjusting gas dispersion is arranged at the lower position of the gas dispersion nozzle 20. It is a simulation result in the case of FIG. 4 in which the nozzle 60B is arranged. In the simulation result of FIG. 9, the concentration of SiCl ₂ is shown in gray scale, and the darker the color (closer to black), the higher the concentration.

From the simulation results shown in Figure 9, under the influence of the N ₂ gas ejected from the concentration control gas dispersion nozzle 60A and 60B, the high concentration region of SiCl _2, compared with the simulation result shown in FIG. 8, It can be seen that the gas moves in the direction of the arrow shown in FIG. 9, that is, in the central portion of the processing container 1. Further, in the simulation result shown in FIG. 9, it can be seen that the high concentration region of SiCl ₂ moves so as to be pushed up toward the upper left of the paper surface. It is considered that this is because the N ₂ gas discharged from the concentration adjusting gas dispersion nozzle 60B flows to the exhaust port 37 so as to go around the lower side of the high concentration region of SiCl ₂ . Further, it can be seen that as the flow rate of the N ₂ gas discharged from the concentration adjusting gas dispersion nozzle 60B increases, the high concentration region moves so as to extend between the gas dispersion nozzle 20 and the exhaust port 37.

(Simulation result of the second example)
Next, the simulation result of the second example shown in FIG. 10 will be described. In the simulation of the second example, in addition to the gas dispersion nozzles 20 and 23, the concentration adjusting gas dispersion nozzle 60C is on the upper side of the side wall portion of the processing container 1 intermediate between the storage compartment wall 32 and the exhaust port 37, and the concentration is on the lower side. This is a simulation result in the case of FIG. 5 in which the adjusting gas dispersion nozzle 60D is arranged. In the simulation result of FIG. 10, the concentration of SiCl ₂ is shown in gray scale, and the darker the color (closer to black), the higher the concentration.

From the simulation results shown in FIG. 10, under the influence of the N ₂ gas ejected from the concentration control gas dispersion nozzle 60C and 60D, the high concentration region of SiCl _2, compared with the simulation result shown in FIG. 8, It can be seen that the gas moves in the direction of the arrow shown in FIG. 10, that is, in the direction of the gas dispersion nozzle 60C. It is considered that this is because the influence of the discharge from the gas dispersion nozzle 60D near the region where the concentration of SiCl ₂ is high is large. Further, the N ₂ gas discharged from the concentration adjusting gas dispersion nozzle 60D is discharged to the lower side of the high concentration region of SiCl ₂ and then flows to the exhaust port 37 on the left side. Therefore, it is considered that the high concentration region of SiCl ₂ moves so as to be pushed up toward the concentration adjusting gas dispersion nozzle 60C. Further, as the flow rate of the N ₂ gas discharged from the concentration adjusting gas dispersion nozzle 60D increases, the high concentration region of SiCl ₂ moves away from the concentration adjusting gas dispersion nozzle 60D and moves toward the concentration adjusting gas dispersion nozzle 60C. You can see that it moves.

(Simulation result of the third example)
Next, the simulation result of the third example shown in FIG. 11 will be described. In the simulation shown in FIG. 11, in addition to the gas dispersion nozzles 20 and 23, the concentration adjusting gas dispersion nozzle 60E is arranged above the exhaust port 37 on the side wall of the processing container 1, and the concentration adjusting gas dispersion nozzle 60F is arranged below. It is a simulation result in the case of FIG. In the simulation result of FIG. 11, the concentration of SiCl ₂ is shown in gray scale, and the darker the color (closer to black), the higher the concentration.

From the simulation results shown in FIG. 11, due to the influence of the N ₂ gas discharged from the concentration adjusting gas dispersion nozzles 60E and 60F, the high concentration region of SiCl ₂ is compared with the simulation result shown in FIG. It can be seen that the movement is in the direction of the arrow shown in, that is, in the direction away from the concentration adjusting gas dispersion nozzles 60E and 60F. Further, from the results shown in FIG. 11, it can be seen that the influence of the N ₂ gas discharged from the concentration adjusting gas dispersion nozzle 60F is stronger. It is considered that this is because the influence of the discharge from the concentration adjusting gas dispersion nozzle 60F near the region where the concentration of SiCl ₂ is high is large. Further, it can be seen that as the flow rate of the N ₂ gas discharged from the concentration adjusting gas dispersion nozzle 60F increases, the high concentration region of SiCl ₂ moves away from the concentration adjusting gas dispersion nozzle 60F.

[Simulation result in the film forming apparatus of the second embodiment]
Next, in addition to the gas dispersion nozzle 20 for discharging the film-forming raw material gas and the carrier gas and the gas dispersion nozzle 23 for discharging the inert gas for purging shown in FIG. 8, the processing container is as shown in the second embodiment. The concentration distribution of SiCl ₂ was simulated when six concentration adjusting gas dispersion nozzles 60A to 60F were arranged around 1. The basic simulation conditions were the same as in the case of the above-mentioned "simulation in the film forming apparatus having the basic configuration", and the flow rates of the gas from the gas dispersion nozzles 20 and 23 were also the same. The concentration adjusting gas dispersion nozzles 60A to 60F were arranged around the wafer W at substantially equal intervals (every 60 degrees).

13 and 14 are diagrams showing the first simulation result and the second simulation result, respectively. In FIGS. 13 and 14, the flow rates of the inert gas (N ₂ gas) discharged from the concentration adjusting gas dispersion nozzles 60A to 60F are different.

In addition, in FIGS. 13 and 14, (a) shows the simulation result of the concentration distribution of SiCl ₂ itself, and (b) is the concentration distribution which standardized the simulation result of (a), that is, the relative concentration distribution. Is shown. In (a), the concentration of SiCl ₂ becomes lower when the amount of the inert gas discharged is large, but the contrast becomes stronger by standardization. The film formation rate decreases as the concentration decreases, but the decrease in film formation rate can be dealt with by increasing the process time. Therefore, since it is sufficient to control the relative concentration distribution of the film-forming raw material gas (or the reactive species), (b) shows the standardized concentration distribution of SiCl ₂ having a strong contrast.

For comparison, FIGS. 12A and 12B show the simulation results of the SiCl ₂ concentration distribution itself and the normalized concentration distribution, that is, the relative concentration distribution, which have the basic configurations shown in FIG. 8, respectively. Shown.

(First simulation result)
In the first simulation shown in FIG. 13, the gas flow rate of the N ₂ gas (inert gas) discharged from the concentration adjusting gas dispersion nozzles 60A to 60F was set to 1000 sccm.

13 from the first simulation results shown in (a) is under the influence of _{N 2} gas discharged from the concentration control gas dispersion nozzle 60a-60f, the high concentration region of SiCl ₂ is, FIG. 12 (a) Compared with the simulation result shown in (1), it can be seen that the gas dispersion nozzle 20 for discharging the film-forming raw material gas moves to the central portion in the processing container 1 so as to extend to the exhaust port 37. Further, it can be seen that the concentration of SiCl ₂ is low (the color is lightened) as a whole because the total flow rate of the N ₂ gas discharged from the concentration adjusting gas dispersion nozzles 60A to 60F is large. On the other hand, according to the normalized concentration distribution of SiCl ₂ in FIG. 13 (b), the high concentration of SiCl ₂ in the central portion in the processing container 1, and lower the concentration of SiCl ₂ in the peripheral portion, SiCl _It can be seen that the concentration distribution of ₂ can be effectively controlled.

(Second simulation result)
In the second simulation shown in FIG. 14, the gas flow rate of the N ₂ gas (inert gas) discharged from the concentration adjusting gas dispersion nozzles 60A to 60F was set as follows.
Gas dispersion nozzle for concentration adjustment 60A: N ₂ gas 100sccm
Gas dispersion nozzle for concentration adjustment 60B: N ₂ gas 500 sccm
Gas dispersion nozzle for concentration adjustment 60C: N ₂ gas 100 sccm
Gas dispersion nozzle for concentration adjustment 60D: N ₂ gas 500 sccm
Gas dispersion nozzle for concentration adjustment 60E: N ₂ gas 7000sccm
Gas dispersion nozzle for concentration adjustment 60F: N ₂ gas 3000 sccm

From a second simulation result shown in FIG. 14 (a), by controlling the _{N 2} gas ejected from the concentration control gas dispersion nozzle 60a-60f, compared with the simulation results shown in FIG. 12 (a) , It can be seen that the high concentration region of SiCl ₂ moves to the central portion in the processing container 1. Further, it can be seen that the high concentration region is controlled to have a shape closer to a circular shape as compared with the example shown in FIG. However, since the total flow rate of the N ₂ gas discharged from the concentration adjusting gas dispersion nozzles 60A to 60F is large, the concentration of SiCl ₂ is low (the color is light) as a whole. On the other hand, according to the normalized concentration distribution of SiCl ₂ in FIG. 14 (b), the high concentration of SiCl ₂ in the central portion in the processing container 1, that the concentration of SiCl ₂ in the peripheral portion is lower It is confirmed more clearly.

As described above, based on the simulation results, the concentration adjusting gas dispersion nozzle is arranged at a predetermined position different from the position where the film-forming raw material gas is discharged around the processing container, and the concentration adjusting inert gas is discharged. It was confirmed that the concentration distribution of the film-forming raw material gas on the wafer can be controlled. In particular, by arranging a plurality of concentration adjusting gas dispersion nozzles around the processing container and controlling the flow rates of these, the concentration of SiCl ₂ can be controlled more effectively, and the concentration is biased toward the exhaust side. It was confirmed that the concentration distribution of SiCl ₂ can be controlled to an ideal distribution in which the central portion of the wafer is high and the peripheral portion is low.

From this, it can be seen that the present embodiment makes it possible to control the distribution of the film-forming raw material gas (reactive species) and suppress the loading effect that occurs in the pattern wafer.

In the experimental example, the concentration distribution of the reactive species produced by thermal decomposition of the film-forming raw material gas is simulated, but if the concentration distribution of the film-forming raw material gas can be controlled, the film-forming raw material gas is thermally decomposed. It is considered that the concentration distribution of the reactive species produced in the above process can also be controlled. Further, by adjusting the flow rates of the inert gas used as the purge gas and the carrier gas in the ALD and the inert gas used as the concentration adjusting gas, the concentration of the film-forming raw material gas (or the reactive species) can also be controlled. That is, both the concentration of the film-forming raw material gas (or the reactive species) and the relative concentration distribution can be controlled.

<Other applications>
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and can be variously modified without departing from the spirit of the present invention.

For example, in the above embodiment, an example in which the present invention is used in the Si deposition step when performing ALD using HCD gas as a Si raw material gas and an oxidizing agent is shown, but the present invention is not limited to this, and other film formations are formed. It is also applicable to the case of performing ALD using a raw material gas and another reaction gas.

Further, in the above embodiment, HCD gas is used as the film-forming raw material gas, and SiCl ₂ generated by thermal decomposition of the HCD gas is used as the reaction-active species, but the film-forming raw material gas itself may be the reaction-active species. ..

Further, although the present invention is effective for short-time processes such as raw material deposition in ALD, it can also be applied during CVD.

Furthermore, the case where a semiconductor wafer is used as the object to be processed has been shown, but it goes without saying that the present invention is not limited to this and can be applied to other substrates such as glass substrates and ceramic substrates for flat panel displays.

1; processing container 5; wafer boat 14; film-forming raw material gas supply mechanism 15; inert gas supply mechanisms 20, 23; gas dispersion nozzle 41; exhaust device 42; heating mechanism 60A to 60F; concentration adjustment gas dispersion nozzle 101, 102, 103, 104; film forming apparatus W; semiconductor wafer (object to be processed)

Claims (17)

The vacuum can be held processing chamber, the object to be processed in several place in multiple stages, a plurality of the object from the film forming material gas supply unit provided at a predetermined position on the side of said plurality of workpiece This is a film forming method in which a film-forming raw material gas is supplied along the surface of the film, and a predetermined film is formed on a plurality of objects to be filmed at once by a reactive species generated from the film-forming raw material gas on the object to be processed. hand,
Said predetermined gas for adjusting the concentration of the concentration control gas supply portion provided in a position different from the concentration distribution of the film forming material gas on the surface of the front Symbol plurality of workpiece is fed to the high portion A film forming method characterized by controlling the concentration distribution of the reactive species on the plurality of objects to be treated by moving a portion having a high concentration distribution in the supply direction of the concentration adjusting gas . The film forming method according to claim 1, wherein the concentration adjusting gas supply unit supplies the concentration adjusting gas to the surfaces of the plurality of objects to be processed from a plurality of positions different from each other. A plurality of objects to be processed are arranged in multiple stages in a processing container capable of holding a vacuum, and a plurality of objects to be processed are provided from a film-forming raw material gas supply unit provided at a predetermined position on the side of the plurality of objects to be processed. This is a film forming method in which a film-forming raw material gas is supplied along the surface, and a predetermined film is formed on a plurality of objects to be processed at once by a reactive active species generated from the film-forming raw material gas on the object to be processed. ,
A plurality of concentration adjusting gas supply units are provided at positions different from the predetermined positions and around the processing container, and the plurality of gas supply units are provided according to the concentration distribution of the film-forming raw material gas on the surface of the plurality of objects to be processed. The concentration of the film-forming raw material gas on the surface of the plurality of objects to be processed is controlled by controlling the supply and stop of the concentration adjusting gas from the concentration adjusting gas dispersion nozzle and the supply amount from each concentration adjusting gas dispersion nozzle. moving the portion of high distribution, film how to and controlling the reaction active species concentration distribution over the plurality of workpiece. The film forming method according to any one of claims 1 to 3, wherein the air is exhausted from a position in the container facing the predetermined position. The film forming method according to any one of claims 1 to 4, wherein the film is formed while rotating the plurality of objects to be processed. The film forming method according to any one of claims 1 to 5, wherein the concentration adjusting gas is an inert gas. The film forming method according to claim 6, wherein the raw material gas is hexachlorodisilane (Si ₂ Cl ₆ ), the reactive active species is SiCl ₂ , and the inert gas is N ₂ gas. When a silicon oxide film is formed by ALD in which Si deposition by hexachlorodisilane and Si oxidation by an oxidizing agent are alternately repeated, the concentration adjusting gas is supplied at the time of Si deposition to carry out the reaction activity. The film forming method according to claim 7, wherein the concentration distribution of SiCl ₂ , which is a seed, is controlled. A film forming apparatus that collectively forms a predetermined film on a plurality of objects to be processed.
A vacuum-holding processing container in which the plurality of objects to be processed are housed and arranged in multiple stages ,
A film-forming raw material gas supply unit provided at a predetermined position on the side of the plurality of objects to be processed and supplying the film-forming raw material gas along the surface of the object to be processed.
A concentration adjusting gas supply unit provided at a position different from the predetermined position and supplying a concentration adjusting gas to the surfaces of the plurality of objects to be treated.
A control unit for controlling the supply of the film-forming raw material gas and the concentration-adjusting gas from the film-forming raw material gas supply unit and the concentration-adjusting gas supply unit is provided.
The control unit
Wherein the film-forming raw material gas supply unit in the processing chamber to supply the film-forming raw material gas to the surface of the object, and the concentration adjusting gas from the concentration adjusting gas supply unit, said plurality of workpiece The film was formed on the plurality of objects to be treated by supplying the film-forming raw material gas to a portion of the surface having a high concentration distribution and moving the portion having a high concentration distribution in the supply direction of the concentration adjusting gas. A film forming apparatus characterized by controlling the concentration distribution of reactive species generated from the raw material gas . The film forming apparatus according to claim 9, wherein the concentration adjusting gas supply unit supplies concentration adjusting gas to the surfaces of the plurality of objects to be processed from a plurality of positions different from each other. A film forming apparatus that collectively forms a predetermined film on a plurality of objects to be processed.
A vacuum-holding processing container in which the plurality of objects to be processed are housed and arranged in multiple stages,
A film-forming raw material gas supply unit provided at a predetermined position on the side of the plurality of objects to be processed and supplying the film-forming raw material gas along the surface of the object to be processed.
A plurality of concentration adjusting gas supply units provided at a position different from the predetermined position and around the processing container to supply the concentration adjusting gas to the surfaces of the plurality of objects to be processed.
A control unit that controls the supply of the film-forming raw material gas and the concentration-adjusting gas from the film-forming raw material gas supply unit and the concentration-adjusting gas supply unit.
Equipped with
The control unit
The film-forming raw material gas is supplied from the film-forming raw material gas supply unit to the surface of the object to be processed in the processing container, and the film-forming raw material gas is supplied to the surface of the plurality of objects to be processed according to the concentration distribution of the film-forming raw material gas on the surface of the plurality of objects to be processed. By controlling the supply and stop of the concentration adjusting gas from the plurality of concentration adjusting gas dispersion nozzles and the supply amount from each concentration adjusting gas dispersion nozzle , the film-forming raw material gas on the surface of the plurality of objects to be processed is controlled. of moving the portions of high density distribution, the plurality of film forming apparatus you and controls the reactive species of the density distribution on the object to be processed. The film forming apparatus according to any one of claims 9 to 11, wherein an exhaust port is provided at a position in the processing container facing the film forming raw material gas supply unit. Further provided with a rotation mechanism for rotating the plurality of objects to be processed,
The control unit
The film forming apparatus according to any one of claims 9 to 12 , wherein the rotation mechanism is controlled to form a film while rotating the plurality of objects to be processed. The film forming apparatus according to any one of claims 9 to 13, wherein the concentration adjusting gas is an inert gas. The film forming apparatus according to claim 14, wherein the raw material gas is hexachlorodisilane (Si ₂ Cl ₆ ), the reactive active species is SiCl ₂ , and the inert gas is N ₂ gas. An oxidant supply unit that supplies an oxidant into the processing container,
Further having a purge gas supply unit for supplying purge gas in the processing container,
The control unit forms a silicon oxide film by ALD that alternately repeats Si deposition by the hexachlorodisilane and oxidation of Si by an oxidizing agent, and supplies the concentration adjusting gas at the time of the Si deposition. The film forming apparatus according to claim 15, wherein the concentration distribution of SiCl ₂ , which is a reactive active species, is controlled. It is a storage medium in which a program for operating on a computer and controlling a film forming apparatus is stored, and the program is such that the film forming method according to any one of claims 1 to 8 is performed at the time of execution. A storage medium characterized in that a computer controls the film forming apparatus.