JP2570594Y2 - Thin film forming equipment - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film forming apparatus used for manufacturing various semiconductor devices, forming a superconducting film on a substrate, forming corrosion-resistant and wear-resistant films on mechanical parts and the like.

[0002]

2. Description of the Related Art As this kind of thin film forming apparatus, ECR is used.
An ECR sputtering apparatus that combines a highly active microwave plasma obtained using (electron cyclotron resonance) with a sputtering method using a solid target as a raw material, and a solid target placed in a high-frequency current or DC electric field and a magnetic field intersecting the electric field There is known a magnetron sputtering apparatus for performing sputtering.

In the ECR sputtering apparatus, a highly active plasma is usually formed by introducing a raw material gas and a microwave into a plasma chamber in which a magnet body is arranged on the outer periphery, and the plasma is irradiated to an object on which a thin film is to be formed. On the other hand, a cylindrical sputter target placed so as to surround the plasma flow from the plasma chamber and applied with a bias voltage is sputtered with some ions in the plasma, and the sputtered particles fly to the target in the plasma flow. Supply.

The ECR sputtering apparatus has an advantage that a thin film can be formed on the surface of an object at a relatively low temperature, and as a result, a thin film having excellent smoothness and a dense and low internal stress can be formed. Further, in the magnetron sputtering apparatus, since electrons move in a cyclotron under the action of an electric field and a magnetic field, high-density plasma is formed, and sputtering of a target is performed smoothly, so that there is an advantage that high-speed film formation is possible.

[0005]

However, in the ECR sputtering apparatus, since the surfaces of the sputter targets face each other and do not face the target, it is difficult for the sputter particles to reach the target smoothly, so that the film is formed. There is a problem that the speed is low and the film does not reach the entire surface of the object uniformly, resulting in poor uniformity of the film.

Accordingly, the present invention utilizes the advantages of the ECR sputtering apparatus, that is, the ability to form a thin film at a relatively low temperature and the advantage of the magnetron sputtering apparatus to form a thin film at a high speed, and to form a thin film capable of forming a good quality thin film at a high speed. It is intended to provide a device.

[0007]

According to the present invention , a gas and a microphone are provided in a plasma chamber in which a magnet body is arranged on the outer periphery.
Microwave to form microwave plasma and form a thin film.
Microwave plasma for irradiating the target to be formed
And a plasma of the microwave plasma generator.
Formed in the outer peripheral area of the chamber,
Is sputtered by a magnetic field intersecting the
Magnetron sputtering for releasing particles to the target
And a plasma chamber of the microwave plasma generator.
It was arranged between the magnetron sputtering unit and the inner periphery.
A magnet body comprising: a cylindrical earth shield wall ; and a magnet body in which the magnetic field generating means of the magnetron sputtering unit is multiplexed and arranged at an interval adjacent to the outer periphery of the plasma chamber.
It includes a holder, nearest the inside of the magnet body to the plasma chamber of said multiplexing of the magnet also serves as a magnet of the microwave plasma generator, the sputter target
Is the magnetic field generated by the magnets in the multiple arrangement toward the object.
The cylindrical earth shield wall can be disposed inside
The magnet holder is disposed closer to the plasma chamber than the magnet holder.
And the end of the cylindrical earth shield wall on the object side.
Part is closer to the target than the position of the sputter target.
It is intended to provide a thin film forming apparatus characterized by protruding into a thin film.

[0008] Each of the magnet bodies in the multiple arrangement of the magnetron sputtering section may be a ring-shaped one as a typical example. Further, a part or all of the holder of the magnet body of the sputtering unit may also serve as a plasma chamber in the microwave plasma generating unit. Each magnet body may be an electromagnet or a permanent magnet. The electric field in the magnetron sputtering unit may be either an alternating current or a direct current.

Furthermore, in order to prevent high-energy particles generated in the magnetron sputtering section from being mixed into the plasma flow from the plasma chamber as much as possible, it is also conceivable to make the electron trap anode face the sputtered particle emission portion of the sputtering section. Can be

[0010]

According to the thin film forming apparatus of the present invention, in the magnetron sputtering section, the gas existing there is turned into plasma by the action of an electric field and a magnetic field, and the sputter target is sputtered smoothly by the ions in the plasma. The sputtered particles are emitted toward the object to be formed.

On the other hand, in the microwave plasma generating section, a low-pressure gas and microwaves are introduced into the plasma chamber, and the action of a magnetic field is applied to form microwave plasma under electron cyclotron resonance to form a thin film. A plasma flow is generated toward the target. The sputtered particles emitted from the sputter section fly in the plasma stream and are supplied to the surface of the object to form a desired thin film on the surface. Said my
The plasma chamber of the plasma generator and the magnetron
There is a cylindrical earth shield wall between the inner periphery of the sputter part
Provided on the object side of the earth shield wall.
The end protrudes toward the target from the sputter target placement position.
Since the out, the release of the sputtered particles is directed to the target compound
The plasma chamber of the microwave plasma generator,
Microwave transmission for microwave introduction in plasma chamber
Window, and there is no danger of deposition.
Particles accumulate in the microwave transmission window in the plasma chamber.
And the sputter target may
Made of metal material or material that does not transmit microwave
If there is, the generation of plasma in the microwave plasma generation part
Although it may affect life, there is no such fear and stable
Microwave plasma can be maintained and metal materials and microwaves can be
Can be used with sputter targets made of materials that do not transmit
Wear. Further, the cylindrical earth shield wall is provided with the magnet
Since it is located closer to the plasma chamber than the holder,
The magnet holder is exposed to microwave plasma and
It is not sputtered based on plasma.
As a result, a high-quality thin film can be formed.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic sectional view of one embodiment, and FIG.
FIG. 5 is a plan view showing an arrangement relationship of main parts in the device of FIG. This thin film forming apparatus has a film forming chamber 1, and the inside thereof can be maintained at a predetermined film forming vacuum degree by an exhaust system 11. A substrate holder 2 is provided in the film forming chamber 1, and a substrate 3 on which a thin film is to be formed is supported on the holder.

A microwave plasma generator 4 is provided below the holder 2, and a magnetron sputtering unit 5 is provided therearound. The plasma generating section 4 includes a plasma chamber 4
1. Waveguide 4 for introducing microwaves into this plasma chamber
2. A gas introduction pipe 43 for introducing gas, and a ring-shaped magnet 44 surrounding the outer periphery of the plasma chamber 41 (a magnetic field in the plasma chamber in the direction of the substrate includes 875 gauss). A ceramic window 421 is provided at the entrance from the waveguide 42 to the chamber 41.

On the other hand, the sputtering unit 5
4, a ring-shaped magnet 51 which is arranged outside the magnet at a predetermined interval, and a holder 52 for both magnets. Double magnet 44,
Of the 51, the inner magnet 44 has an S pole at the top and an N pole at the bottom, the outer magnet 51 has an N pole at the top,
It has an S pole at the bottom. The upper ends of both magnets are aligned at the same height.

The magnet holder 52 is used for the inner magnet 4.
4 rises in a cylindrical shape along the inner circumference of
The upper magnets 4 and 51 cover the upper end surfaces and the gap between them, and further fall down in a cylindrical shape along the outer periphery of the outer magnet 51, and then extend outward in a horizontal flange shape. Water W for temperature control can flow in the gap between the two magnets 44 and 51.

The holder 52 is connected to the film forming chamber 1 via an insulating portion 53.
Is connected to the lower end. Upper surface 522 of holder 52
Also serves as a support surface of the sputter target 6, and the target is supported here and directed to the substrate 3. An earth shield plate 54 is put on the holder 52,
This plate body has a double ring shape as a whole in plan view, and a window 541 through which the target 6 can face the substrate 3.
(Between the double rings), and is covered with the holder 52 and the target 6 thereon.
1 and move downward along the cylinder, and
When the earth shield wall is formed between the plasma chamber 1
Together, they form the peripheral wall of the plasma chamber 41. Also figure
As shown in FIG.
The end on the substrate 3 side supported by the solder 2 is a sputter target.
It protrudes from the arrangement position toward the substrate.

Further, the anode 7 is arranged in a double ring shape at a position facing the window 541 of the shield plate 54. The film forming chamber 1 and the earth shield plate 54 are grounded, the high frequency power supply 55 is connected to the magnet holder 52, and the positive voltage application power supply 71 is connected to the anode 7. The positional relationship between the plasma chamber 41, the magnets 44 and 51, and the target 6 as viewed from above is as shown in FIG. In FIG. 2, a broken line indicates the target 6 and a dashed line indicates the magnet 4.
4 and 51 are shown.

According to the thin film forming apparatus described above, the substrate 3 is mounted on the substrate holder 2, the ring-shaped sputter target 6 is disposed on the upper surface 522 of the magnet holder 52, and the sputter target 6 is provided through the window 541 of the earth shield plate 54. Pointed at substrate 3. In this state, the inside of the film forming chamber 1 is maintained at a predetermined film forming vacuum degree of about 10 ^-5 to 10 ^-4 Torr by the exhaust system 11.

Further, in the microwave plasma generating section 4, an inert gas and / or a reactive gas corresponding to a thin film to be formed are introduced into the plasma chamber 41 at a degree of vacuum of 10 ^-5 to 10 ^-4.
While being introduced at a low pressure so as to maintain about Torr, a microwave of 2.45 GHz is introduced from the waveguide 42. Thus, the plasma is formed in the plasma chamber 41 by the ECR effect under the action of the magnetic field of the magnet 44, and the plasma flow P from the plasma chamber 41 to the substrate 3 is generated.
Occurs and persists.

On the other hand, in the magnetron sputtering section 5, a high-frequency voltage is applied from a power supply 55 to the magnet holder or the target holder 52, and the magnetic field generated by the two magnets 44 and 51 acts in a direction orthogonal to the electric field, thereby producing a relatively high density. Is generated, and the target 6 is efficiently and smoothly sputtered by the ions in the plasma, and sputtered particles S are emitted from the window 541 of the shield plate, and fly in the plasma flow to uniformly cover the entire surface of the substrate 3. To reach. Thus, the desired thin film is uniformly formed at a relatively low temperature over the entire surface at a high speed.

The high-energy electrons generated in the magnetron sputtering unit 5 are trapped by the anode 7 to which a positive voltage is applied, and the adverse effects caused by mixing a large amount of the high-energy electrons into the plasma flow can be more reliably prevented. plasma
Holder for chamber 41 and magnetron sputtering unit 5
52 and a cylindrical shape that is a part of the earth shield plate 54
An earth shield wall 542 is provided and
The end on the substrate side projects from the sputter target 6 toward the substrate side.
The sputtered particles are emitted toward the substrate 3.
Inside the plasma chamber 41, especially for the microwave introduction.
It moves to the lamic window 421 and there is no danger of deposition.
The sputter particles are deposited on the ceramic window 421
And the sputter target 6 is made of metal
Made of materials or materials that do not transmit microwaves
Can interfere with the generation of microwave plasma.
No need to worry about maintaining stable microwave plasma
Made of metallic materials or materials that do not transmit microwaves
Can also be used with putter targets. In addition, cylindrical grounding
The field wall 542 is a plasma chamber from the magnet holder 52.
41, the magnet holder is
Exposure to microwave plasma and spa based on the plasma
The thin film of good quality
Can be achieved.

[0022]

According to the thin film forming apparatus of the present invention, there are the following advantages. Low energy ion irradiation by ECR microwave plasma and magnetron sputtering can be used in combination, so that low-temperature and high-speed film formation can be achieved by ion assist and magnetron sputtering. Further, since low-temperature film formation is possible, a high-quality film can be formed. Since the microwave plasma generation unit using ECR is used, it is possible to maintain a plasma flow reaching a target on which a thin film is to be formed at a low film forming gas pressure, and thus to form a film with a higher purity. The sputtered particles are emitted toward the target object, and there is almost no possibility that they will migrate to the microwave plasma generation part.
The magnet holder of the magnetron sputter
Since it is not exposed to the microwave plasma, a high quality thin film can be formed. Since a magnetic field required for ECR conditions can be obtained by a magnet used for magnetron sputtering, it can be manufactured in a small and inexpensive manner despite the above advantages. The microwave plasma generation unit and the magnetron sputtering unit are independent of each other except that a part of the magnet body is used in combination, so that individual control is possible. Metal materials and microwaves as sputter targets
A material made of a material that does not transmit light can also be used.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an embodiment of the present invention.

FIG. 2 is a diagram showing an arrangement relation of a main part in the apparatus of FIG. 1 in a plan view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Film-forming chamber 11 Exhaust system 2 Substrate holder 3 Substrate 4 Microwave plasma generation part 41 Plasma chamber 42 Microwave waveguide 421 Ceramic window 43 Gas introduction pipe 44 Magnet 5 Magnetron sputtering part 51 Magnet 52 Magnet holder 53 Insulation member 54 Earth shield Plate 541 Window of shield plate 55 High frequency power supply 6 Sputter target 7 Anode 71 Positive voltage application power supply

Claims (3)

(57) [Scope of request for utility model registration] 1. A gas chamber in which a magnet body is disposed on the outer periphery.
And microwaves to form microwave plasma
To irradiate the target object on which a thin film is to be formed.
A microwave plasma generator, and the microwave plasma generator
Formed in the outer peripheral area of the plasma chamber
Is sputtered by an electric field and a magnetic field intersecting it.
And a mug for discharging the sputtered particles to the target.
A netron sputtering unit and the microwave plasma generation unit
Plasma chamber and the inner periphery of the magnetron sputtering unit
A magnet ground and a magnet holder, wherein the means for generating a magnetic field of the magnetron sputtering unit includes a magnet body and a magnet holder arranged adjacent to the outer periphery of the plasma chamber at intervals. closest inner magnet body to the plasma chamber of said multiplexing of the magnet also serves as a magnet of the microwave plasma generator, the spa
The target is placed in the multiple arrangement magnetic field toward the object.
The cylindrical arc can be placed in a magnetic field by a stone body.
The shield wall is separated from the magnet holder by the plasma.
In front of the cylindrical earth shield wall
The end on the object side is the position of the sputter target.
A thin film forming apparatus characterized by projecting further toward the object. 2. The thin film forming apparatus according to claim 1, wherein each of the multiple magnets arranged in the magnetron sputtering unit is a ring-shaped magnet. 3. The thin film forming apparatus according to claim 1, wherein an electron trapping anode faces a sputtered particle emitting portion of the magnetron sputtering unit.