JP2014152348A - Film deposition device and film deposition method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film deposition device and a film deposition method capable of separately adjusting a density and an injection speed of radical molecules or radical atoms generated from plasma.SOLUTION: A film deposition device generates plasma using gas in a film deposition space, and has an injector for injecting radical with a film component generated from the plasma to a film depositing substrate. The injector includes: a plasma actuator having a pair of electrodes, generating the plasma by applying a voltage between the pair of electrodes, and injecting the radical with the film deposition component generated from the plasma; and a plasma generation element having a pair of electrodes, generating the plasma by applying the voltage between the electrodes, and generating the radical with the film deposition component. The plasma actuator and the plasma generation element are provided in a vertical line in a vertical direction on a face of the film depositing substrate, so as to deposit a film by injecting the radical with the film deposition component injected from the injector to the film depositing substrate.

Description

  The present invention relates to a film forming apparatus and a film forming method using plasma.

  Conventionally, when a thin film is formed on a substrate, a plasma processing apparatus is often used. In particular, a parallel plate type plasma processing apparatus having a simple structure is often used in a film production line. In this parallel plate type plasma processing apparatus, for example, high frequency power of 13.6 MHz is used.

However, it has been known that the parallel plate type plasma processing apparatus has the following problems.
・ It is difficult to generate spatially uniform plasma in a wide film formation space corresponding to a large film formation substrate.
・ The throughput of the film formation process is low, and ・ The collision of ions and electrons with the film formation substrate increases as the supply power increases, and the film surface is not smooth.
The above problem is a greater obstacle to today's diversifying film forming processes.

On the other hand, when a silicon oxide film or the like is formed by plasma CVD using silane or the like on a large-area substrate, a CVD apparatus is known that suppresses the generation of particles and prevents ions from entering the substrate (patent) Reference 1).
The CVD apparatus is a CVD apparatus that generates plasma in a vacuum container to generate radicals, and performs film formation on the substrate with the radicals and silane. Specifically, a partition that separates the inside of the vacuum container into two chambers, a plasma generation space and a film formation processing space, is provided. A plurality of through holes and diffusion holes are formed in the partition wall. Silane or the like is supplied to the internal space, and the silane or the like is introduced into the film formation processing space through the diffusion hole. Radicals generated in the plasma generation space are introduced into the film formation processing space through the through holes. The through hole satisfies the condition of uL / D> 1, where u is the gas flow velocity in the hole, L is the substantial hole length, and D is the mutual gas diffusion coefficient.

JP 2000-345349 A

In the CVD apparatus, radicals generated in the plasma generation space are introduced into the film formation processing space through the through holes, and the material gas such as silane directly forms the film without touching the plasma through the internal space of the partition wall and the diffusion holes. Since it is introduced into the space, a violent chemical reaction between the material gas and the plasma can be prevented, and as a result, generation of particles can be suppressed and ion incidence to the substrate can be prevented. Furthermore, the material gas can be introduced uniformly, and radicals such as oxygen gas can be uniformly supplied to the film formation processing space through a plurality of through holes formed in the partition wall. It is said that the film can be effectively deposited on a large area substrate.
However, in the above CVD apparatus, when the film thickness to be formed cannot be made uniform, the density of radicals (radical molecules and radical atoms) generated from plasma is adjusted uniformly, or radicals generated from plasma Although it can be considered that the spraying speed for spraying the film toward the substrate for film formation is adjusted uniformly, the above CVD apparatus cannot perform such adjustment.

  Accordingly, an object of the present invention is to provide a film forming apparatus and a film forming method capable of separately adjusting the density and jetting speed of radical molecules and radical atoms generated from plasma.

One embodiment of the present invention is a film formation apparatus using plasma.
The film forming apparatus
A film forming container having a film forming space in which a film forming substrate is disposed and a film forming gas is introduced;
An injector that is provided in the film formation space, generates plasma using a gas in the film formation space, and injects radical molecules or radical atoms of a film formation component generated from the plasma onto the film formation substrate; Have.
The injector has a pair of actuator electrodes, and generates a plasma using the gas in the film formation space by applying a voltage between the actuator electrodes, and the gas in the film formation space by the generation of the plasma. A plasma actuator that injects radical molecules or radical atoms of the film forming component generated from the plasma, and
Having a pair of plasma generation electrodes, applying a voltage between the plasma generation electrodes generates plasma using the gas in the film formation space, and generates radical molecules or radical atoms as film formation components from the plasma And a plasma generating element.
At this time, the plasma actuator and the plasma generating element are provided in tandem in a direction perpendicular to the surface of the film formation substrate, and radical molecules or radical atoms of the film formation component ejected from the injector are applied to the film formation substrate. The film is formed by spraying.

A preferred form of the film forming apparatus is as follows.
The actuator electrode and the plasma generation electrode are annular electrodes.
The plasma actuator is provided with the actuator electrode along the circumference of the first dielectric tube at different positions in the length direction of the first dielectric tube and the first dielectric tube. The first electrode located far from the film formation substrate is exposed when viewed from the space in the first dielectric tube, and the second electrode located near the film formation substrate is exposed to the first electrode. The first dielectric tube is covered with a dielectric as viewed from the space inside the first dielectric tube.
The plasma generating element includes the second dielectric tube and the plasma generating electrode provided at different positions in the length direction of the second dielectric tube along the circumference of the second dielectric tube. All of the electrodes are covered with the dielectric of the second dielectric tube as viewed from the space in the second dielectric tube.

At this time, the actuator electrode of the plasma actuator is provided along openings on both sides of a through hole provided in the first plate,
One end of the first dielectric tube is provided so as to coincide with the end of the first opening of the through hole located far from the film formation substrate of the actuator electrode,
The first electrode is provided along an edge of the first opening of the through hole,
It is preferable that the second electrode is provided along a circumference of the second opening of the through hole on the side opposite to the first opening.

Furthermore, it is preferable that the plasma generation electrode of the plasma generation element is provided along openings on both sides of a through hole provided in the second plate.
It is preferable that the central axis of the through hole provided in the second plate coincides with an extension line of the central axis of the through hole provided in the first plate.

In a preferred embodiment of the film forming apparatus, the plasma actuator and the plasma generating element use a third dielectric tube as a common tube.
The plasma generation element and the plasma actuator are provided in a column in the order of the plasma generation element and the plasma actuator when viewed from the film formation substrate side.
Of the plasma actuator electrodes, the third electrode of the plasma actuator at a position far from the film formation substrate is exposed when viewed from the space in the third dielectric tube and is close to the film formation substrate. The fourth electrode of the plasma actuator is covered with a dielectric of the third dielectric tube as viewed from the space in the third dielectric tube.
Of the plasma generation electrodes, the fifth electrode of the plasma generation element that is far from the film formation substrate and the sixth electrode of the plasma generation element that is close to the film formation substrate are When viewed from the space in the third dielectric tube, it is covered with the dielectric of the third dielectric tube. At this time, the fourth electrode and the fifth electrode are the same electrode.

Another embodiment of the present invention is a film formation apparatus using plasma. The film forming apparatus
A film forming container having a film forming space in which a film forming substrate is disposed and a film forming gas is introduced;
Having a pair of actuator electrodes, generating a plasma using the gas in the film formation space by applying a voltage between the actuator electrodes, and sucking the gas in the film formation space by the generation of the plasma; Furthermore, a plasma actuator that ejects radical molecules or radical atoms of the film forming component generated from the plasma,
A pair of plasma generation electrodes provided in the film formation space, and applying a voltage between the plasma generation electrodes to generate plasma using a gas in the film formation space; A plasma generating element for generating radical molecules or radical atoms of
A power source for supplying a voltage for plasma generation to the plasma actuator and the plasma generation element in order to generate plasma in the plasma actuator and the plasma generation element;
And a control unit for controlling supply of the voltage.
The plasma actuator includes a plurality of through holes penetrating in the thickness direction of an actuator plate, a dielectric tube provided in each of the through holes, and the pair of actuators provided in openings on both sides of the through holes. It has an electrode.
The plasma generating element includes a plurality of through holes penetrating in a thickness direction of a plasma generating plate, a dielectric tube provided in each of the through holes, and the pair of openings provided on both sides of each of the through holes. Having a plasma generating electrode.

At this time, preferably, the through holes of each of the plasma actuator and the plasma generation plate are arranged in a lattice form so as to form a plurality of columns and rows along two directions on the surface,
Of the plurality of electrodes provided on the one surface side of each of the pair of plasma generation electrodes and the pair of actuator electrodes, the electrodes positioned in each common row are first for each row. Connected in series with each other via a feeder line and connected to the power source,
Of the plurality of electrodes provided on the other surface side of the plate among the pair of plasma generation electrodes and the pair of actuator electrodes, the electrodes located in each common column are Two power supply lines are connected in series with each other and connected to the power source.

  At this time, the voltage for generating the plasma is supplied to each of the actuator electrode and the plasma generation electrode by switching a positive voltage value or a negative voltage value in a pulse shape in a set cycle unit. It is preferred that

  It is preferable that the central axis of the through hole provided in the plasma generation unit coincides with an extension line of the central axis of each through hole provided in the plasma actuator.

Yet another embodiment of the present invention is a film formation method using plasma. The film formation method is as follows:
Introducing a film forming gas into a film forming space in which the film forming substrate is disposed;
A step of generating a plasma using a gas in the film formation space, and injecting a radical molecule or a radical atom of a film formation component generated from the plasma onto the film formation substrate.
The film forming step includes a step of sucking a gas in the film forming space to generate a force for injecting the radical molecule or the radical atom, and a step of generating the radical molecule or the radical atom. Generating plasma from the gas in the membrane space. In the film forming method, the adjustment of the force in the step of generating the force and the adjustment of the intensity of the plasma in the step of generating the plasma are performed separately.

  In the above-described film forming apparatus and film forming method, the density of the radical molecules and radical atoms generated from the plasma and the jetting speed can be adjusted separately. Thereby, for example, a uniform film can be formed on the deposition substrate.

It is a schematic structure figure of the whole film-forming apparatus of this embodiment. It is an external appearance perspective view of the plate used for the plasma actuator and plasma generation element which are used by this embodiment. (A) It is a cross-sectional perspective view of the principal part of the plasma actuator of this embodiment, (b) is an external appearance perspective view of the principal part shown to (a). It is a figure explaining the production | generation of the plasma in the plasma actuator of this embodiment. It is a figure which shows the photograph of light emission by the production | generation of the plasma in the plasma actuator of this embodiment. It is a figure explaining the production | generation of the plasma in the plasma production element of this embodiment. It is a figure explaining the modification of the plasma actuator and plasma generation element which are used by this embodiment. It is a figure explaining the other modification of the plasma actuator used by embodiment.

  Hereinafter, the film forming apparatus and the film forming method of the present invention will be described in detail.

(Outline explanation of the film deposition system)
First, an outline of the film forming apparatus of this embodiment will be described.
The film forming apparatus includes a film forming container and an injector. A film formation substrate is disposed in the film formation container. The film forming container includes a film forming space into which a film forming gas is introduced.
The injector is provided in a film formation space, generates plasma using a gas in the film formation space, for example, a film formation gas, and forms radical molecules or radical atoms of the film formation components generated from the plasma on the film formation substrate. Spray.
The injector includes a plasma actuator and a plasma generating element.
The plasma actuator has a pair of actuator electrodes. By applying a voltage between the actuator electrodes, plasma is generated using the gas in the film formation space, and the gas in the film formation space is sucked by the generation of this plasma. Further, radical molecules or radical atoms of film forming components generated from this plasma are injected.
The plasma generation element has a pair of plasma generation electrodes. By applying a voltage between the plasma generation electrodes, plasma is generated using the gas in the film formation space, and radical molecules or radicals of the film formation components are generated from the plasma. Generate atoms.
Here, the plasma actuator and the plasma generation element are provided in tandem with respect to the direction perpendicular to the surface of the film formation substrate. The film formation apparatus forms a film by injecting radical molecules or radical atoms of a film formation component injected from such an injector onto the film formation substrate.

Here, the plasma actuator and the plasma generation element described above are the same in that they generate plasma, but in addition to generating plasma, the plasma actuator sucks gas (gas in the film formation space) from one side. However, it differs from a plasma generating element in that it functions as an actuator that creates an induced flow that injects gas (radical molecules or radical atoms) from the other side. That is, the intensity of the generated plasma can be adjusted by the plasma actuator and the plasma generating element. For this reason, the density of radicals (radical molecules, radical atoms) generated from plasma can be adjusted. Furthermore, the ejection speed of the radical molecules and radical atoms, which are film-forming components generated from the plasma, from the injector can be adjusted by the plasma actuator. Therefore, when adjusting the injection speed, the operation of the plasma actuator is enhanced. At this time, since the intensity of the generated plasma is increased at the same time, the operation of the plasma generating element is lowered. By reducing the intensity of the plasma generated by the plasma generating element, it is possible to increase the injection speed of the radical molecules and radical atoms while keeping the density of the radical molecules and radical atoms generated from the injector constant. Further, by increasing the operation of the plasma generating element while keeping the operation of the plasma actuator constant, the density of the radical molecules and radical atoms can be increased while keeping the injection speed of the radical molecules and radical atoms constant.
A plurality of sets of such plasma actuators and plasma generating elements are provided at positions facing the film formation substrate, and the operations of the plurality of sets are individually controlled, so that the film formed on the film formation substrate can be controlled. The thickness can be made a desired distribution, for example, and the film quality can be made uniform.

(Deposition system)
FIG. 1 is an overall schematic configuration diagram of a film forming apparatus 10 of the present embodiment. The film forming apparatus 10 includes a film forming main body 12, a gas source 14, an exhaust unit 16, and a plasma generation unit 18.
The film forming body 12 mainly includes a film forming container 20 and a susceptor 22. The film formation container 20 is a container for maintaining the film formation space in the film formation container 20 at a predetermined pressure, or maintaining the pressure at a predetermined pressure and performing a film formation process on the film formation substrate in the film formation space. is there. The susceptor 22 has a mounting surface 26 on which a film formation substrate 24 is placed, and is provided in the film formation space. A heater (not shown) is provided inside the susceptor 22 to heat the film formation substrate 24. The film formation substrate 24 is carried into the film formation container 20 from the outside through an open shutter (not shown) provided in the film formation container 20 and placed on the placement surface 26 of the susceptor 22. In addition, the film formation substrate 24 that has been formed is carried out of the film formation container 20 through the shutter.

  A supply port 28 connected to a pipe (not shown) connected to the gas source 14 is provided on the ceiling surface of the film forming container 20. The film forming gas supplied from the gas source 14 is supplied into the film forming container 20 through the supply port 28. An exhaust port 30 for exhausting unnecessary gas in the film formation space in the film formation container 20 is provided on the floor surface of the film formation container 20. The exhaust port 30 is connected to a pipe (not shown) connected to the exhaust unit 16. Thereby, the film formation space is maintained at a constant pressure.

An injector 32 belonging to the plasma generation unit 18 is provided above the susceptor 22 in the film formation space. The injector 32 includes an actuator plate 34 including a plurality of plasma actuators, and a plasma generation plate 36 including a plurality of plasma generation elements.
Each of the actuator plate 34 and the plasma generation plate 36 is a dielectric substrate made of resin or glass plate. Each of the actuator plate 34 and the plasma generation plate 36 has a plurality of through holes 38 and 40 (see FIG. 2) penetrating in the plate thickness direction, and generates plasma inside the through holes 38 and 40. The through hole 38 is provided in the actuator plate 34, and the through hole 40 is provided in the plasma generation plate 36. In FIG. 2, the through hole 40 and the plasma generation plate 36 are written in parentheses. The actuator plate 34 and the plasma generation plate 36 will be described later. In FIG. 2, the actuator electrodes 34a and 34b and the dielectric tube 34c are not shown.

  The gas source 14 is, for example, a film forming gas source such as silane gas or hydrogen gas, and is a gas containing a thin film component formed on the film forming substrate 24. When a microcrystalline silicon film is formed as a thin film on the deposition substrate 24, for example, silane gas and hydrogen gas are used as the deposition gas. In this case, a silane gas source and a hydrogen gas source are separately prepared as the gas source 14, and the silane gas and the hydrogen gas are supplied to the film formation space at a predetermined flow rate ratio between the silane gas and the hydrogen gas.

  The exhaust unit 16 includes a rotary pump or a dry pump, and maintains the film formation space at a constant pressure. Further, when the pressure in the film formation space is made lower than the atmospheric pressure, the exhaust unit 16 exhausts to a predetermined pressure.

The plasma generation unit 18 includes the injector 32, the first control unit 44, the second control unit 46, and the high-frequency power source 42 described above.
The actuator plate 34 constituting the injector 32 is a plate provided in the film forming container 20, and includes a plurality of through-holes 38 penetrating in the thickness direction of the plate, and openings on both sides of the through-holes 38. A pair of actuator electrodes provided around each of the electrodes and a dielectric tube provided in each of the through holes 38 so as to penetrate the through holes 38 are provided. The through-hole 38, the actuator electrode, and the dielectric tube constitute a plasma actuator described later.

  The plasma generation plate 36 constituting the injector 32 is a plate provided in the film forming container 20, and includes a plurality of through holes 40 penetrating in the thickness direction of the plate, and both sides of the through holes 40. A pair of actuator electrodes provided around the opening and a dielectric tube provided in each of the through holes 40 so as to penetrate the through holes 40 are provided. The through-hole 40, the actuator electrode, and the dielectric tube constitute a plasma generation element to be described later.

The actuator plate 34 and the plasma generation plate 36 are provided in tandem in the direction perpendicular to the surface of the film formation substrate 24 when viewed from the film formation substrate 24. As shown in FIG. 1, the plasma generation plate 36, the actuator plate 34, and the film formation substrate 24 are arranged in this order from above in the film formation space. Therefore, the plasma actuator and the plasma generation element are provided in a column in the vertical direction of the surface of the film formation substrate 24, and the plasma actuator is provided at a position close to the film formation substrate 24 and the plasma generation element is provided at a position far from the film formation substrate 24. ing.
As in the present embodiment, when the actuator plate 34 and the plasma generation plate 36 are separated from each other, it is preferable that the plasma actuator and the plasma generation element are provided in order from the deposition substrate 24. This is for effectively adjusting the distribution of film thickness based on the injection speed by effectively utilizing the injection speed of radical molecules and radical atoms by the plasma actuator. Needless to say, a plasma generating element and a plasma actuator may be provided in the order from the deposition substrate 24.

(Plasma actuator)
3A is a cross-sectional perspective view of the main part of the plasma actuator of the present embodiment, and FIG. 3B is an external perspective view of the main part shown in FIG.
The plasma actuator 35 is provided on the actuator plate 34.
The plasma actuator 35 has a pair of actuator electrodes 34a and 34b. By applying a voltage between the actuator electrodes 34a and 34b, plasma is generated using the gas in the film formation space, and the film formation space is generated by generating plasma. The inside gas is sucked, and further, radical molecules or radical atoms of film forming components generated from the plasma are injected. That is, the plasma actuator 35 is an element that creates an induced flow by generating plasma.
Such an element preferably has the following form.

  That is, the actuator electrodes 34a and 34b are annular electrodes. The plasma actuator 35 is provided with actuator electrodes 34a and 34b along the circumference of the dielectric tube 34c at different positions in the length direction of the dielectric tube 34c (first dielectric tube) and the dielectric tube 34c. The actuator electrode 34a located far from the film formation substrate 24 is exposed as viewed from the space in the dielectric tube 34c. The actuator electrode 34b located near the film formation substrate 24 is covered with the dielectric of the dielectric tube 34c as viewed from the space inside the dielectric tube 34c. In the example of FIGS. 3A and 3B, the actuator electrode 34b is provided so as to surround the outer periphery of the dielectric tube 34c.

The actuator electrode 34 a is connected to a power supply line 34 d formed on the surface of the actuator plate 34. The power supply line 34d is connected to the second control unit 46 shown in FIG. 1, and a high-frequency voltage pulse, for example, is supplied as electric power through the power supply line 34d to the actuator electrode 34a. The actuator electrode 34b is connected to a ground conductor 34f provided on the actuator plate 34. The ground conductor 34 f is grounded via the second control unit 46. Therefore, the potential of the actuator electrode 34b is zero.
In the plasma actuator 35, the intensity of the plasma P and the ejection speed of radical molecules and radical atoms are adjusted by the power applied to the actuator electrodes 34a and 34b. Therefore, the density of radical molecules and radical atoms generated from the plasma P and the jetting speed thereof are adjusted by the power applied to the actuator electrodes 34a and 34b.

As shown in FIG. 3A, the plasma actuator 35 has the following configuration as a preferred form.
Specifically, the annular actuator electrodes 34a and 34b of the plasma actuator 35 are provided along openings on both sides of a through hole 38 (see FIG. 2) provided in the actuator plate 34 (first plate). One end of the dielectric tube 34c (first dielectric tube) (the upper end in FIG. 3A) is the first of the openings on both sides of the through hole 38 that is far from the film formation substrate 24. It is provided so as to coincide with the end of the opening. Moreover, the actuator electrode 34 a (first electrode) is provided along the edge of the first opening of the through hole 38. The inner circumference of the actuator electrode 34a coincides with the inner circumference of the dielectric tube 34c. Therefore, the actuator electrode 34a is arranged along the inner circumference of the dielectric tube 34c so that the inner circumference of the actuator electrode 34a is along the inner circumference of the dielectric tube 34c at the upper end of the dielectric tube 34c in FIGS. 3 (a) and 3 (b). Provided.
On the other hand, the annular actuator electrode 34b (second electrode) is provided along the circumference of the second opening of the through hole 38 on the side opposite to the first opening. The inner circumference of the actuator electrode 34b is configured to coincide with the outer circumference of the dielectric tube 34c below the dielectric tube 34c in FIGS. 3A and 3B, and the actuator electrode 34b is configured to match the outer circumference of the dielectric tube 34c. It is provided along.
Therefore, the actuator electrode 34a is exposed when viewed from the space inside the dielectric tube 34c, and the actuator electrode 34b is covered with the dielectric of the dielectric tube 34c when viewed from the space inside the dielectric tube 34c.

With this configuration, when the actuator electrode 34a is supplied with power, plasma is generated by the voltage between the actuator electrode 34a and the actuator electrode 34b. FIG. 4 is a diagram for explaining the induced flow caused by the generation of plasma.
By applying a voltage to the actuator electrodes 34a and 34b, a plasma P using a gas in the film forming space, for example, a film forming gas, is generated between the actuator electrodes 34a and 34b. At this time, the actuator electrode 34a far from the film formation substrate 24 is exposed as viewed from the space in the dielectric tube 34c, and the actuator electrode 34b close to the film formation substrate 24 is a dielectric as viewed from the space in the dielectric 34c. Since the tube 34c is covered with the dielectric, the generated plasma P generates a force pulling from the actuator electrode 34a toward the actuator electrode 34b. The force generated by the generation of such plasma P is, for example, “Experimental Investigation of DBD Plasma Actuators Driven by Repetitive High Voltage Nanosecond Pulses with DC or Low-Frequency Sinusoidal Bias” (Dmitry F. Opaits et al., 38 ^th AIAA Plasmadynamics and Lasers Conference <br> in conjunction with the <br> 16 ^th , 25-28 June 2007). Therefore, the actuator 35 of the present embodiment also functions as an actuator that sucks the film forming gas and injects radical molecules and radical atoms generated from the plasma P.
Although the said injection speed changes with electric power supplied to the actuator electrode 34a and the pressure reduction atmosphere of the film-forming space, for example, an injection speed of 0.1 m / second to 2 m / second can be obtained.
As described above, when the plasma P is generated in the dielectric tube 34c, which is the space in the through hole 38, using the gas in the film formation space, a pulling force is generated in FIG. The radical molecules and radical atoms generated by the above are pulled by the second opening below the through-hole 38, and jetted downward so as to diffuse from the second opening.

FIG. 5 is a diagram of light emission of plasma P generated in each plasma actuator 35 from the actuator electrode 34a side in an actuator plate 34 provided with five vertical and five horizontal plasma actuators 35. FIG. Of the five vertical and five horizontal plasma actuators 35, the plasma emission intensity of the nine plasma actuators located inside is shown.
In the actuator 35 of the present embodiment, the through hole 38 and the dielectric tube 34c are formed in a circular tube shape, and the actuator electrodes 34a and 34b are also formed in an annular shape, but these shapes are limited to a circular tube shape or an annular shape. Not. The cross sections of the through hole 38 and the dielectric tube 34c may be rectangular, and the actuator electrodes 34a and 34b may also be rectangular ring shapes.

(Plasma generator)
FIG. 6 is a diagram for explaining plasma generation in the plasma generation element 37 of the present embodiment.
The plasma generation element 37 is provided on the plasma generation plate 36.
The plasma generating element 37 includes a pair of annular plasma generating electrodes 36a and 36b and a dielectric tube 36c (second dielectric tube). The plasma generation electrodes 36a and 36b are provided along the circumference of the dielectric tube 36c at different positions in the length direction of the dielectric tube 36c. Both of the plasma generation electrodes 36a and 36b are covered with the dielectric of the dielectric tube 36c when viewed from the space of the dielectric tube 36c.
As shown in FIG. 6, the plasma generation electrodes 36a and 36b are preferably provided along openings on both sides of the through-hole 40 provided in the plasma generation unit 36 (second plate). The configuration of the plasma generation element 37 is different from the plasma actuator 35 in that the plasma generation electrode 36a far from the film formation substrate 24 is covered with a dielectric compared to the plasma generation electrode 36b. Other configurations are the same as those of the plasma actuator 35. Therefore, the description of the configuration of the plasma generation element 37 is omitted. As for the plasma generating element, the through hole 40 and the dielectric tube 36c are formed in a circular tube shape, and the plasma generating electrodes 36a and 36b are also formed in an annular shape, but these shapes are formed in a circular tube shape or an annular shape. Not limited. The cross sections of the through hole 40 and the dielectric tube 36c may be rectangular, and the plasma generation electrodes 36a and 36b may also be rectangular ring shapes.

FIG. 6 is a view for explaining generation of plasma P.
By applying a voltage to the plasma generation electrodes 36a and 36b through a power supply line (not shown), plasma P is generated by the gas in the film formation space between the plasma generation electrodes 36a and 36b. At this time, the plasma generation electrode 36a far from the film formation substrate 24 and the plasma generation electrode 36b close to the film formation substrate 24 are both covered with the dielectric of the dielectric tube 36c as viewed from the space in the dielectric 36c. Therefore, unlike the plasma actuator 37, no induced flow occurs. That is, the plasma generating element 37 only generates the plasma P by the supplied power.
The plasma generation electrodes 36a and 36b are connected to the first control unit 44 shown in FIG. 1, and the plasma generation electrode 36a is supplied with power, for example, high-frequency voltage pulses, through a power supply line (not shown). The plasma generation electrode 36 b is grounded via the first control unit 44. Therefore, the potential of the plasma generation electrode 36b is zero.
In the plasma generating element 37 having such a configuration, the intensity of the plasma P is controlled by the power applied to the plasma generating electrodes 36a and 36b. Therefore, the density of radical molecules and radical atoms generated from the plasma P is controlled by the power applied to the plasma generation electrodes 36a and 36b.

The first control unit 44 and the second control unit 46 are connected to the high-frequency power source 42, and the first control unit 44 and the second control unit 46 each plasma actuator 35 and each plasma generation element 37 according to desired control information. The power supplied to each of the plasma actuators 35 and the plasma generation elements 37 is individually supplied with power adjusted.
For example, the power to be supplied is a high frequency of 10 kHz to 100 MHz, and a voltage pulse generated with a constant high frequency voltage is used. At this time, the first control unit 44 and the second control unit 46 use a switching circuit (not shown) to control the number of voltage pulses per unit time or control the pulse width to supply the supplied power. Can be controlled.
In the present embodiment, it is induced by the plasma actuator 35 that the central axis of the through hole 40 provided in the plasma generation plate 36 coincides with the extension of the central axis of the through hole 38 provided in the actuator plate 34. This is preferable in that the flow (gas suction and injection) is also effectively used for radical molecules and radical atoms generated by the plasma generation element 37.

(Modification 1)
FIG. 7 is a diagram illustrating a first modification of the present embodiment. In this modification, the plasma actuator 35 and the plasma generating element 37 are configured using one plate and one dielectric tube.
In this element, the plasma actuator 35 and the plasma generation element 37 use one dielectric tube 34c, 36c (third dielectric tube) as a common tube. When viewed from the film forming substrate 24 side, the plasma generating elements 37 and the plasma actuators 35 are provided in a column in this order. As shown in FIG. 7, the plasma actuator 35 and the plasma generating element 37 are arranged in this order from the top in the drawing.

Of the plasma actuator electrodes 34a and 34b, the actuator electrode 34a (third electrode) located far from the film formation substrate 24 is exposed as viewed from the space inside the one dielectric tube 34c and 36c, and is used for film formation. The actuator electrode 34b (fourth electrode) located close to the substrate 24 has one dielectric tube 34c, 36c (third electrode) as viewed from the space in one dielectric tube 34c, 36c (third dielectric tube). Covered with a dielectric of a dielectric tube).
Of the plasma generation electrodes 36a and 36b, the plasma generation electrode 36a (fifth electrode) located far from the film formation substrate 24 and the plasma generation electrode 36b (sixth electrode) located closer to the film formation substrate 24 ) Is covered with the dielectric of the dielectric tubes 34c and 36c when viewed from the space inside the dielectric tubes 34c and 36c. The actuator electrode 34b and the plasma generation electrode 36a are the same electrode. Hereinafter, this electrode is referred to as actuator / plasma generating electrode 34b, 36a.

The actuator electrode 34a, the actuator / plasma generation electrodes 34b and 36a, and the plasma generation electrode 36b are connected to the third control unit 41 through a power supply line (not shown). The third control unit 41 is connected to the high frequency power source 42.
Regarding the power supply to the actuator electrode 34a, the actuator / plasma generation electrodes 34b and 36a, and the plasma generation electrode 36b, the power is adjusted by adjusting the voltage pulse by the third control unit 41 as in the above embodiment. Therefore, by adjusting the voltage pulse supplied to the actuator electrode 34a with the actuator / plasma generating electrodes 34b and 36a as a reference, the voltage supplied to the plasma generating electrode 36b with the actuator / plasma generating electrodes 34b and 36a as a reference. By adjusting the pulse, it is possible to control the density and ejection speed of desired radical molecules or radical atoms from this element.

  In this modification, the plasma actuator 35 is provided upward (at a position far from the film formation substrate 24), and the plasma generation element 37 is provided below (at a position close to the film formation substrate 24). The arrangement is different from the form. In this modification, since the plasma actuator 35 and the plasma generating element 37 are shared by one dielectric tube, the plasma actuator 35 is arranged above to generate an induced flow above the one dielectric tube 34c, 36c. In addition, the ejection speed of radical molecules and radical atoms ejected from below one dielectric tube 34c, 36c is maintained. Since the actuator electrode 34a is provided so as to be exposed when viewed from the inner space of one of the dielectric tubes 34c and 36c, it is preferable to provide the plasma actuator 35 above from the viewpoint of arranging the actuator electrode 34a. . Of course, the plasma actuator 35 can be provided downward (at a position close to the film formation substrate 24) and the plasma generating element 37 can be provided upward (at a position far from the film formation substrate 24).

(Modification 2)
Next, a second modification of the present embodiment is shown.
FIG. 8 is a diagram illustrating the actuator plate 34. In the second modification, the actuator plate 34 shown in FIG. 8 is used as the actuator plate shown in FIG. 1, and a plasma generation plate (not shown) adopting a configuration in which the electrode on the upper surface of the actuator plate 34 shown in FIG. Is used as the plasma generation plate shown in FIG.

  The plasma actuator of Modification 2 includes a plurality of through holes penetrating in the thickness direction of the actuator plate, a dielectric tube provided in each of the through holes, and a pair of actuators provided in openings on both sides of each of the through holes. It has an electrode. On the other hand, the plasma generating element includes a plurality of through holes penetrating in the thickness direction of the plasma generating plate, a dielectric tube provided in each of the through holes, and a pair of plasmas provided in openings on both sides of each through hole. It has a generation electrode. In this respect, it is not different from the embodiment described above.

Specifically, in Modification 2, the through holes of each of the plasma actuator and the plasma generation plate are arranged in a lattice shape so as to form a plurality of columns and rows along two directions on the surface. Of the plurality of electrodes provided on the one surface side of each of the pair of plasma generation electrodes and the pair of actuator electrodes, the electrode located in each common row has one power supply line (first line) 1 power supply line) and connected to the power source in series. Further, among the plurality of electrodes provided on the other surface side of the plate among the pair of plasma generation electrodes and the pair of actuator electrodes, the electrode positioned in each common column includes a feed line (for each column). The second power supply line) is connected in series with each other and connected to the power source.
The configurations of the plasma actuator and the plasma generating element provided on each plate are the same as those shown in FIGS.

  In the actuator plate 34, a plurality of through holes 38 of the same size penetrating in the plate thickness direction are provided in a grid pattern in a regular manner along the X and Y directions in the figure. A group of through holes 38 aligned along the Y direction is referred to as a column, and a group of through holes 38 aligned along the X direction is referred to as a row. In the example shown in FIG. 8, the plasma actuator is provided in each of the through holes formed by the columns 7 and 7. However, the number of columns and the number of rows is not limited to 7 and may be a plurality of numbers. That's fine.

On one surface of the actuator plate 34, power supply lines 50U _{1 to} 50U ₇ connected to seven plasma actuators arranged in the X direction are provided. On the other surface of the actuator plate 34, feed lines 50D _{1 to} 50D ₇ connected to seven plasma actuators arranged in the Y direction are provided. The feed lines 50U _{1 to} 50U ₇ are connected to actuator electrodes located above the actuator plate 34 that are exposed when viewed from the space in the dielectric tube provided in each of the through holes. The feeder lines 50D _{1 to} 50D ₇ are connected to actuator electrodes located below the actuator plate 34 covered with the dielectric of the dielectric tube as viewed from the space inside the dielectric tube.

One end (the left end in FIG. 8) of the power supply lines 50U _{1 to} 50U ₇ is connected to the upper control unit 46U, and the upper control unit 46U is further connected to the upper power supply 42U. The other ends (the right end in FIG. 8) of the power supply lines 50U _{1 to} 50U ₇ are grounded via a capacitor (not shown). Upper control unit 46U so as to supply the desired voltage pulses to the power supply lines _50U 1 _{~50U 7,} so that the voltage pulses are generated respectively based on the desired control signal U1～U7. Therefore, the power applied to each of the power supply lines 50U _{1 to} 50U ₇ is common.

On the other hand, one end (upper end in FIG. 8) of the power supply lines 50D _{1 to} 50D ₇ is connected to the lower control unit 46D, and the lower control unit 46D is further connected to the lower power supply 42D. . The other ends (the lower ends in FIG. 8) of the power supply lines 50D _{1 to} 50D ₇ are grounded via a capacitor (not shown). Lower control unit 46D so as to supply the desired voltage pulses to the feed line _50D 1 _{~50D 7,} so that the voltage pulses are generated respectively based on the desired control signal L1 to L7. Therefore, the electric power applied to each of the feeder lines 50D _{1 to} 50D ₇ is common.

Thus, when the voltage difference voltage pulses of power supply lines _50U 1 _{~50U 7} to the feed line _50D 1 _{~50D 7} occurs in the feed line _50U 1 _{~50U 7} intersection of the feed line _50D 1 _{~50D 7} The positioned plasma actuator 17 operates to generate plasma P and induced flow due to generation of plasma P.
Thus, as desired operations in the plasma actuator 17 located in the feed line _50U 1 _{~50U 7} intersection of the feed line _50D 1 _{~50D 7} occurs, the feed line _50U 1 _{~50U 7} to the feed line _50D 1 _~50D The timing of the voltage pulse applied to ₇ and the pulse width of the voltage pulse are determined. Therefore, the voltage pulses applied to the power supply lines 50U _{1 to} 50U ₇ and the power supply lines 50D _{1 to} 50D ₇ can be controlled by adjusting the upper control unit 46U and the lower control unit 46D. The adjustment by the upper control unit 46U and the lower control unit 46D is performed based on the control signals U1 to U7 and the base control signals L1 to L7. The control signals U1 to U7 and the base control signals L1 to L7 are created by a computer (not shown), for example, and supplied to the upper control unit 46U and the lower control unit 46D.

  In the plasma generation plate, as described above, the plasma generation electrode is formed by covering the plasma actuator electrode provided above the actuator unit 34 shown in FIG. 8 with a dielectric layer. For this reason, unlike the plasma actuator, the plasma generation element of the plasma generation unit generates the plasma P without generating an induced flow. The plasma generation plate is configured in the same manner as the actuator plate, and power is supplied to each electrode through the power supply line. Therefore, the plasma generation element located at the intersection of the power supply line provided on the upper side of the plate and the power supply line provided on the lower side is Plasma generation is performed and plasma P is generated.

Therefore, the timing of the voltage pulse applied to the upper power supply line and the lower power supply line and the voltage pulse so that a desired operation occurs in the plasma generating element located at the intersection of the upper power supply line and the lower power supply line. The pulse width is determined. Therefore, the voltage pulse applied to the upper power supply line and the lower power supply line can be controlled by adjusting the upper control unit and the lower control unit. The adjustment by the upper control unit and the lower control unit is performed based on control signals sent to the upper control unit and the lower control unit. This control signal is generated by, for example, a computer (not shown) and supplied to the upper control unit and the lower control unit.
In this case, each of the actuator electrode of the plasma actuator and the plasma generation electrode of the plasma generation element switches the positive voltage value or the negative voltage value in a pulse form in a set cycle unit, thereby generating plasma. It is preferable that the voltage is supplied in terms of controlling the power to be supplied.

  In the second modification, when the actuator plate and the plasma generation plate are provided apart from each other in the film formation space as shown in FIG. 1, the actuator plate is positioned closer to the film formation substrate 24 than the plasma generation plate. It is preferable to provide them in that the ejected radical molecules and radical atoms are effectively deposited on the film formation substrate 24. In particular, it is preferable that the central axes of the through holes provided in the plasma generation unit coincide with the extension lines of the respective central axes of the through holes provided in the plasma actuator from the viewpoint of efficiently depositing on the film formation substrate 24.

(Film formation method)
Hereinafter, a film forming method performed by the film forming apparatus of this embodiment shown in FIG. 1 will be described. Since the film forming methods in the first and second modifications are the same, the description thereof is omitted.
First, in the film forming apparatus 10, the exhaust unit 16 is driven so that the atmosphere of the film forming space in the film forming container 12 is maintained at a constant pressure. On the other hand, a film forming gas is constantly introduced from the gas source 14 into the film forming space at a predetermined flow rate. At this time, the film formation substrate 24 is placed on the susceptor 22. That is, the film forming gas is introduced into the film forming space where the film forming substrate 24 is disposed.
Thereafter, the film formation substrate 24 is formed. Specifically, plasma is generated using the gas in the film formation space, and radical molecules or radical atoms of film formation components generated from the plasma are jetted onto the film formation substrate 24 to form a film. More specifically, the gas in the film formation space is sucked to generate a force for injecting radical molecules or radical atoms. That is, plasma generation and induced flow are generated using a plasma actuator. At the same time, in order to generate radical molecules or radical atoms, plasma is generated from the film forming gas using a plasma generating element.

  At this time, the adjustment of the force that generates the induced flow and the adjustment of the plasma intensity are performed separately. The induced flow is generated only by the plasma actuator, and the adjustment of the plasma intensity is generated by the plasma actuator and the plasma generating element. Therefore, the adjustment of the force that generates the induced flow is performed by controlling the power supplied to the plasma actuator, specifically, the number of voltage pulses and the pulse width. On the other hand, the adjustment of the plasma intensity is performed by controlling the power supplied to the plasma actuator and the plasma generating element, specifically, the number of pulses per unit time and the pulse width of the voltage pulse.

Therefore, the adjustment of the force that generates the induced flow and the adjustment of the plasma intensity can be performed separately. The force that generates the induced flow corresponds to the injection speed of radical molecules and radical atoms generated from the plasma, so the power supplied to the plasma actuator is controlled to control the injection amount of radical molecules and radical atoms. Can do.
Since the intensity of the plasma corresponds to the density of radical molecules and radical atoms generated from the plasma, the density of radical molecules and radical atoms can be controlled by controlling the power supplied to the plasma actuator and the plasma generation element. it can.

  As described above, the film forming apparatus and the film forming method of the present embodiment use the plasma actuator 35 and the plasma generating element 37. The plasma actuator 35 and the plasma generating element 37 are provided in tandem in the direction perpendicular to the surface of the film formation substrate 24, and inject the radical molecules or radical atoms of the film formation components injected from the injector 32 onto the film formation substrate 24. Thus, the density of the radical molecules and radical atoms generated from the plasma and the jetting speed can be adjusted separately.

  As described above, the film forming apparatus and the film forming method of the present invention have been described in detail. However, the present invention is not limited to the above-described embodiments and modifications, and various improvements and modifications can be made without departing from the gist of the present invention. Of course.

DESCRIPTION OF SYMBOLS 10 Film-forming apparatus 12 Film-forming container 14 Gas source 16 Exhaust unit 18 Plasma generation unit 20 Film-forming container 22 Susceptor 24 Film-forming substrate 26 Placement surface 28 Supply port 30 Exhaust port 32 Injector 34 Actuator plates 34a and 34b Actuator electrode 34c Dielectric tube 34d Feed line 34f Ground conductor 35 Plasma actuator 36 Plasma generation plates 36a, 36b Plasma generation electrode 36c Dielectric tube 37 Plasma generation elements 38, 40 Through hole 42 High frequency power supply 42U Upper power supply 42D Lower power supply 44 First control unit 46 the second control unit 46U upper control unit 46D lower control unit _{50U 1 ~50U 7, 50D 1 ~50D} 7 feed line

Claims (11)

A film forming apparatus using plasma,
A film forming container having a film forming space in which a film forming substrate is disposed and a film forming gas is introduced;
An injector that is provided in the film formation space, generates plasma using a gas in the film formation space, and injects radical molecules or radical atoms of a film formation component generated from the plasma onto the film formation substrate; Have
The injector has a pair of actuator electrodes, and generates a plasma using the gas in the film formation space by applying a voltage between the actuator electrodes, and the gas in the film formation space by the generation of the plasma. A plasma actuator that injects radical molecules or radical atoms of the film forming component generated from the plasma, and
Having a pair of plasma generation electrodes, applying a voltage between the plasma generation electrodes generates plasma using the gas in the film formation space, and generates radical molecules or radical atoms as film formation components from the plasma A plasma generating element that includes:
The plasma actuator and the plasma generating element are provided in a vertical line in a direction perpendicular to the surface of the film formation substrate, and inject radical molecules or radical atoms of a film formation component injected from the injector onto the film formation substrate. A film forming apparatus characterized in that a film is formed. The actuator electrode and the plasma generation electrode are annular electrodes,
The plasma actuator is provided with the actuator electrode along the circumference of the first dielectric tube at different positions in the length direction of the first dielectric tube and the first dielectric tube. The first electrode located far from the film formation substrate is exposed when viewed from the space in the first dielectric tube, and the second electrode located near the film formation substrate is exposed to the first electrode. Covered with a dielectric of the first dielectric tube as viewed from the space inside the dielectric tube,
The plasma generating element includes the second dielectric tube and the plasma generating electrode provided at different positions in the length direction of the second dielectric tube along the circumference of the second dielectric tube. 2. The film forming apparatus according to claim 1, wherein each of the electrodes is covered with a dielectric of the second dielectric tube as viewed from a space in the second dielectric tube. The actuator electrode of the plasma actuator is provided along openings on both sides of a through hole provided in the first plate,
One end of the first dielectric tube is provided so as to coincide with the end of the first opening of the through hole located far from the film formation substrate of the actuator electrode,
The first electrode is provided along an edge of the first opening of the through hole,
The film forming apparatus according to claim 2, wherein the second electrode is provided along a circumference of the second opening of the through hole on the opposite side to the first opening.   The film formation apparatus according to claim 3, wherein the plasma generation electrode of the plasma generation element is provided along openings on both sides of a through hole provided in the second plate.   The film forming apparatus according to claim 4, wherein a central axis of the through hole provided in the second plate coincides with an extension line of a central axis of the through hole provided in the first plate. The plasma actuator and the plasma generating element use a third dielectric tube as a common tube,
The plasma generation element and the plasma actuator are provided in a column in the order of the plasma generation element and the plasma actuator when viewed from the film formation substrate side,
Of the plasma actuator electrodes, the third electrode of the plasma actuator at a position far from the film formation substrate is exposed when viewed from the space in the third dielectric tube and is close to the film formation substrate. The fourth electrode of the plasma actuator is covered with the dielectric of the third dielectric tube as viewed from the space in the third dielectric tube;
Of the plasma generation electrodes, the fifth electrode of the plasma generation element that is far from the film formation substrate and the sixth electrode of the plasma generation element that is close to the film formation substrate are Covered with the dielectric of the third dielectric tube as viewed from the space in the third dielectric tube;
The film forming apparatus according to claim 1, wherein the fourth electrode and the fifth electrode are the same electrode. A film forming apparatus using plasma,
A film forming container having a film forming space in which a film forming substrate is disposed and a film forming gas is introduced;
Having a pair of actuator electrodes, generating a plasma using the gas in the film formation space by applying a voltage between the actuator electrodes, and sucking the gas in the film formation space by the generation of the plasma; Furthermore, a plasma actuator that ejects radical molecules or radical atoms of the film forming component generated from the plasma,
A pair of plasma generation electrodes provided in the film formation space, and applying a voltage between the plasma generation electrodes to generate plasma using a gas in the film formation space; A plasma generating element for generating radical molecules or radical atoms of
A power source for supplying a voltage for plasma generation to the plasma actuator and the plasma generation element in order to generate plasma in the plasma actuator and the plasma generation element;
A control unit for controlling the supply of the voltage,
The plasma actuator includes a plurality of through holes penetrating in the thickness direction of an actuator plate, a dielectric tube provided in each of the through holes, and the pair of actuators provided in openings on both sides of the through holes. Having electrodes,
The plasma generating element includes a plurality of through holes penetrating in a thickness direction of a plasma generating plate, a dielectric tube provided in each of the through holes, and the pair of openings provided on both sides of each of the through holes. A film forming apparatus comprising: a plasma generating electrode. The through holes of each of the plasma actuator and the plasma generation plate are arranged in a lattice form so as to form a plurality of columns and rows along two directions on the surface,
Of the plurality of electrodes provided on the one surface side of each of the pair of plasma generation electrodes and the pair of actuator electrodes, the electrodes positioned in each common row are first for each row. Connected in series with each other via a feeder line and connected to the power source,
Of the plurality of electrodes provided on the other surface side of the plate among the pair of plasma generation electrodes and the pair of actuator electrodes, the electrodes located in each common column are The film forming apparatus according to claim 7, wherein the film forming apparatuses are connected in series to each other by two power supply lines and connected to the power source.   Each of the actuator electrode and the plasma generation electrode is supplied with the voltage for generating the plasma by switching a positive voltage value or a negative voltage value in a pulse manner in a set cycle unit. The film forming apparatus according to claim 8.   The component axis according to any one of claims 7 to 10, wherein a central axis of the through hole provided in the plasma generation unit coincides with an extension line of a central axis of each through hole provided in the plasma actuator. Membrane device. A film forming method using plasma,
Introducing a film forming gas into a film forming space in which the film forming substrate is disposed;
A step of generating a plasma using a gas in the film formation space, and injecting a radical molecule or radical atom of a film formation component generated from the plasma onto the film formation substrate;
The film forming step includes a step of sucking a gas in the film forming space to generate a force for injecting the radical molecule or the radical atom, and a step of generating the radical molecule or the radical atom. Generating plasma from a gas in the membrane space,
The film forming method, wherein the adjustment of the force in the step of generating the force and the adjustment of the intensity of the plasma in the step of generating the plasma are performed separately.

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