JPH11256334A - Formation of cn thin film and cn thin film forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a CN thin film forming method capable of forming a CN thin film in a high yield and to provide a CN thin film forming device. SOLUTION: A gaseous starting material is introduced into an ion source chamber 2, is ionized and is drawn out from the ion source chamber 2 as an ion beam 7. This ion beam 7 is subjected to mass spectrometry by an ion separating chamber 30A, and only prescribed ion seeds are injected toward a deflecting chamber 30B. In the deflecting chamber 30B, the ion beam 7 is deflected, and, in a speed reducing chamber 5, its speed is reduced, and after that, it is applied to a substrate 62. As the gaseous starting material, the one in which a dipole moment reaches >=0.1 debye at the time of the ionization is preferable, and, e.g. methylamine is used. Moreover, it is preferable that the ions of the gaseous starting material are applied by the energy of 10 eV to 10 keV.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a technique for forming a CN thin film, and more particularly to a technique for forming a CN thin film using a low energy ion beam.

[0002]

2. Description of the Related Art In recent years, a CN thin film has been proposed as a kind of hard thin film. FIG. 2 shows a schematic configuration of a conventional film forming apparatus for forming a CN thin film. As shown in FIG. 2, the film forming apparatus 100 is configured to introduce a nitrogen gas N ₂ from a gas introducing unit 103 into a vacuum processing tank 102 in which a substrate 101 as a film forming target is disposed. . Then, a plasma generating means 104 for discharging the introduced nitrogen gas (N ₂ ) is provided in the vacuum processing tank 102.
And an evaporation source 106 for evaporating carbon (C) as the evaporation material 105. Also, the substrate 101
Is heated by a heater 107 disposed in the vicinity thereof.

In order to form a CN thin film using this film forming apparatus, carbon as an evaporation material 105 is evaporated in an evaporation source 106, and the vapor is guided toward a substrate 101. The generated nitrogen gas is discharged by the plasma generating means 104, and the substrate 101 is irradiated with the excited nitrogen. Thus, a CN thin film 108 is formed on the substrate 101.

[0004]

However, in the case of such a conventional technique, since carbon and nitrogen are used as the raw materials of the CN thin film 108, C is originally unstable.
There is a problem that an N thin film cannot be formed with high yield.

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the prior art, and has as its object to provide a CN thin film forming method and a film forming apparatus capable of forming a CN thin film with high yield. Things.

[0006]

According to a first aspect of the present invention, there is provided a method for ionizing a predetermined source gas in a vacuum and irradiating the source gas with low energy ions. A CN thin film forming method comprising forming a CN thin film on a substrate.

According to the first aspect of the present invention, the raw material gas is ionized in a vacuum to form polar molecules. As a result, carbon atoms and nitrogen atoms are regularly bonded on the object to be processed, and the CN thin film is formed. Are formed in good yield.

Various gases can be used as the predetermined source gas for forming the CN thin film, but the dipole moment at the time of ionization is 0.1 debye or more as in the second aspect of the present invention. Are preferred.

In particular, from the viewpoint of easy handling, methylamine (CH ₃ N
Preference is given to using H ₂ ).

[0010] In order to make the present invention more effective, 10 eV to 10 ke
It is preferable to irradiate the ions of the source gas with energy of V, more preferably 50 eV to 500 eV.

If the irradiation energy of the source gas is smaller than 10 eV, it is difficult to control the chemical bonding, and if it is larger than 10 keV, there is a problem that the film-forming object is greatly damaged.

On the other hand, the invention according to claim 5 provides a vacuum processing tank, gas introducing means for introducing a predetermined amount of a raw material gas for the CN thin film into the vacuum processing tank, and the gas introduction means introduced into the vacuum processing tank. A CN thin film forming apparatus comprising: an ion source for ionizing a source gas; and low-energy ion irradiation means for irradiating an object to be formed with an ion beam extracted from the ion source.

According to the fifth aspect of the present invention, C is produced in high yield.
A film forming apparatus capable of forming an N thin film can be easily obtained.

In this case, as in the sixth aspect of the present invention,
In the third aspect of the present invention, it is also effective to have an ion separating means for separating the ion beam extracted from the ion source into predetermined ion species.

According to the sixth aspect of the present invention, the object to be formed is irradiated with the ion beam separated into the predetermined ion species by the ion separating means, so that the CN film can be formed with higher yield. A device can be obtained.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of a CN thin film forming method and a film forming apparatus according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic configuration diagram illustrating a film forming apparatus according to the present embodiment. As shown in FIG. 1, a film forming apparatus 1 according to the present embodiment includes an ion source chamber (ion source) 2, a main chamber 3, a bellows chamber 4, a deceleration chamber 5, and a sample chamber 6.
Is a low energy ion irradiation apparatus integrally formed.

The ion source chamber 2, the deceleration chamber 5, and the sample chamber 6 include:
A module chamber 20, a deceleration electrode chamber 50, and a target chamber 60 are provided, respectively.
The module chamber 20 is connected to one end of the main chamber 3 and the other end is connected to the module chamber 20.
The bellows chamber 4, the insulator 51, the deceleration electrode chamber 50, and the target chamber 60 are connected in this order, and the inside of the vacuum processing tank constituted by the chambers 20, 3, 4, 50, and 60 is evacuated. ing. Here, the pressure in the vacuum processing tank during the processing is, for example, 1
The pressure is set to about 0 ^-5 to 10 ^-6 Pa. The length of the bellows chamber 4 is adjustable.

The module chamber 20, the main chamber 3, and the bellows chamber 4 are electrically connected so that they have the same potential. Further, the deceleration electrode chamber 50 and the target chamber 60 are also electrically connected to each other so that they have the same potential. On the other hand, the insulator 51 provided between the bellows chamber 4 and the deceleration electrode chamber 50 is configured so that different voltages can be applied to the main chamber 3 side and the target chamber 60 side.

Inside the module chamber 20, an ionizer 21 is provided in a state of being electrically insulated from the module chamber 20, and a filament 22 is provided in the ionizer 21. Ionizer 21
Is connected to a source gas source (not shown) via a flow control device 23. The flow rate control device 23 supplies methylamine (CH), which is a raw material gas for the CN thin film, to the ionizer 21.
₃ NH ₂ ) and the like can be introduced in a certain amount in an evacuated state. When the filament 22 is energized to a temperature of about 1000 ° C. to emit thermoelectrons, plasma of the source gas is generated and ionized. For example, when methylamine is used as a source gas, CH ₃ and N
H ₂ is polarized.

An acceleration electrode 24 and an acceleration / deceleration electrode 25 are provided between the ionizer 21 and the main chamber 3 in this order. The acceleration electrode 24 and the acceleration / deceleration electrode 25 are connected to the module chamber 20 and the ionizer 21.
Provided in an electrically insulated state. An ion outlet 21a is provided at a portion of the ionizer 21 facing the acceleration electrode 24. Further, the acceleration electrode 24
The accelerating / decelerating electrode 25 has a passage hole 17 for passing the ion beam 7 coaxially with the ion outlet 21a.
a and 17b are provided.

In the case of the present embodiment, a positive voltage is applied to the ionizer 21 and a negative voltage is applied to the accelerating electrode 24. The ions in the ionizer 21 are extracted as the ion beam 7 from the ion outlet 21a. After passing through the through holes 24 a and 25 a of the acceleration electrode 24 and the acceleration / deceleration electrode 25, it is injected into the main chamber 3.

The ion beam 7 extracted from the ionizer 21 by the acceleration electrode 24 is first
(For example, about 100 V) and a voltage (for example, about 10 V) obtained by superimposing a voltage applied to the filament 22. Then, at the position where the acceleration electrode 24 is reached, the potential of the acceleration electrode 24 becomes equal to (for example, about 5 kV to 20 kV).

In order to decelerate the ion beam 7, the potential of the acceleration / deceleration electrode 25 is set higher than that of the acceleration electrode 24 (the potential of the acceleration / deceleration electrode 25 is about 2 kV). Becomes the potential (7 kV to 22 kV) at the position reaching the acceleration / deceleration electrode 25.

The main chamber 3 into which the ion beam 7 that has passed through the passage holes 24a and 25a enters has a shape that is bent in a substantially right-angle direction, and when viewed from the ion source chamber 2, the ion separation chamber 30A in order. And a deflection chamber 30B. The ion beam 7 first enters the ion separation chamber 30A as the ion separation means. The potential of the ion beam 7 does not change in the main chamber 3 and in the bellows chamber 4 at the subsequent stage.

An ion separator 31 composed of an electromagnet is provided in the ion separation chamber 30A.
Is subjected to Lorentz force by a magnetic field formed by the ion separator 31, and its trajectory is bent according to the ratio of charge to mass.

The ion separation chamber 30A is curved at a predetermined radius, performs mass spectrometry by adjusting the magnetic field intensity formed by the ion separator 31, and stores only predetermined ion species in the next stage of the deflection chamber 30.
It is configured to emit light toward B.

When the mass analysis is performed, the ion beam 7 is focused by the ion separator 31, passes through the collimator 32, and enters the deflection chamber 30B.

A deflector 33 is provided in the deflection chamber 30B, and the ion beam 7 entering the deflection chamber 30B is
The light enters the deflector 33.

The deflector 33 has a plate-like first deflection electrode 34.
And a second deflecting electrode 35 formed substantially in a “<” shape toward the deceleration chamber 5. These first and second deflecting electrodes 34 and 35 are opposed to each other such that the portion on the side of the ion separation chamber 30A is parallel, while the interval between the portions on the side of the bellows chamber 4 in the next stage is widened.

A positive voltage is applied to the first deflecting electrode 34 with respect to the second deflecting electrode 35, so that the positively charged ion beam 7 entering the deflector 33 is
And is attracted to the second deflecting electrode 35, and its trajectory is bent toward the second deflecting electrode 35. On the other hand, non-charged neutral particles generated by recombination of electrons and ions and mixed in the ion beam 7 are not bent in the deflector 33 but proceed straight along the axis of the incident ion beam 7.

A neutral particle removing plate 52 is provided at the entrance of the deceleration chamber 5 at the subsequent stage of the bellows chamber 4, and an ion decelerator 53 and a ground electrode 54 are provided in this order behind the plate. I have.

A slit 52a is provided at the center of the neutral particle removing plate 52, and the ion beam 7 whose trajectory is bent by the deflector 33 is focused toward the slit 52a in the vicinity thereof. With such a configuration, while the ion beam 7 passes through the slit 52a, the neutral particles that go straight collide with the neutral particle removing plate 52, and
a cannot be passed. As described above, the neutral particles are removed from the ion beam 7 by the slits 52 a of the neutral particle removing plate 52.

The ion beam 7 having passed through the slit 52a of the neutral particle removing plate 52 enters an ion decelerator 53 at a subsequent stage. The ion reducer 53 is formed of a cylindrical electrode, and is disposed so that the central axis thereof coincides with the axis of the ion beam 7.

The ion decelerator 53 includes an acceleration / deceleration electrode 25
Is applied to the neutral particle removing plate 52.
The ion beam 7 before it reaches the ion reducer 53
The ions inside are decelerated and rise to the potential of the ion decelerator 53.

The ion beam 7 is once focused in front of the ion decelerator 53 and diverges when entering the ion decelerator 53, but when the ion beam 7 passes through the ion decelerator 53 The light is decelerated and focused, and then emitted toward the ground electrode 54 at the subsequent stage. The ground electrode 54 is placed at the ground potential together with the deceleration electrode chamber 50, and the ion beam 7 that has passed through the ion decelerator 53 rises in potential, and
At the position where the voltage reaches.

At the center of the ground electrode 54, a through hole 54a is provided, and the ion beam 7 passes through the through hole 54a.
a through the target chamber 6 of the sample chamber 6 at the subsequent stage.
Injected toward 0.

The target chamber 60 is set at the ground potential, and has a Faraday cup 6 inside.
1 and a substrate holder 63 for holding a substrate 62 which is a film formation target. Here, the substrate holder 63 is configured to heat the substrate 62 to a temperature of 77K to 1100K. Further, an ammeter 64 is connected to the Faraday cup 61.

Then, the ion beam 7 entering the target chamber 60 causes the substrate 6
The two surfaces are irradiated with ions. At this time, the value of the current flowing according to the ion beam 7 passing through the Faraday cup 61 is detected by the ammeter 64 so that the substrate 6
2 is measured.

As described above, according to the present embodiment,
By ionizing the source gas in a vacuum, the substrate 62
Above, carbon atoms and nitrogen atoms can be regularly bonded, and thereby a CN thin film can be formed with a high yield.

In particular, in the present embodiment, since the ion beam 7 is separated into predetermined ion species by mass spectrometry, a CN thin film can be formed with higher yield.

It should be noted that the present invention is not limited to the above-described embodiment, and various changes can be made. For example,
In the above-described embodiment, methylamine is used as a raw material gas for the CN thin film. However, the present invention is not limited to this, and another material can be used. However, it is preferable to use methylamine, which is the easiest to handle.

In the above-described embodiment, an ion irradiation apparatus for separating an ion beam into predetermined ion species by mass spectrometry is used. However, an apparatus configured to directly irradiate an ionized source gas to a substrate is used. It is also possible to use. However, when the apparatus as in the above embodiment is used, a CN thin film can be formed with higher yield.

[0043]

As described above, according to the method and apparatus of the present invention, a CN thin film can be formed with a high yield.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a film forming apparatus according to the present invention.

FIG. 2 is a schematic configuration diagram of a conventional film forming apparatus for forming a CN thin film.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Film-forming apparatus 2 ... Ion source room (ion source) 3 ... Main chamber 4 ... Bellows chamber 5 ... Reduction chamber 6 ...
Sample chamber 20 ... Module chamber 50 ... Deceleration electrode chamber 60 ... Target chamber 23 ... Flow control device (gas introduction means) 30A ... Ion separation chamber (ion separation means) 30B ... Deflection chamber 62 ... Substrate (film formation target)

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroyuki Fukasawa 2500 Hagizono, Chigasaki-shi, Kanagawa Prefecture, Japan Vacuum Engineering Co., Ltd. (72) Inventor Yoshiaki Agawa 2500 Hagizono, Chigasaki-shi, Kanagawa Japan, Japan Vacuum Engineering Co., Ltd. (72) Inventor Toshihiro Terasawa 2500 Hagizono, Chigasaki-shi, Kanagawa Japan Vacuum Engineering Co., Ltd.

Claims (6)

[Claims] 1. A method of forming a CN thin film, comprising: ionizing a predetermined source gas in a vacuum; and irradiating the ions of the source gas with low energy to form a CN thin film on an object to be formed. . 2. The method for forming a CN thin film according to claim 1, wherein a source gas having a dipole moment at the time of ionization of 0.1 debye or more is used. 3. The method for forming a CN thin film according to claim 1, wherein methylamine is used as a source gas. 4. The method according to claim 1, wherein the source gas is irradiated with ions at an energy of 10 eV to 10 keV.
4. The method for forming a CN thin film according to any one of claims 1 to 3. 5. A vacuum processing tank, gas introducing means for introducing a predetermined amount of a CN thin film source gas into the vacuum processing tank, and an ion source for ionizing the source gas introduced into the vacuum processing tank. And a low-energy ion irradiating means for irradiating an ion beam extracted from the ion source to a film formation target. 6. The CN thin film forming apparatus according to claim 5, further comprising an ion separating means for separating an ion beam extracted from the ion source into predetermined ion species.