JPH05311429A - Thin film forming device - Google Patents

Abstract

PURPOSE:To enable the formation of a thin film having good quality at a high speed by combining a laser sputtering method, ECR microwave CVD method and DC plasma CVD method and accelerating the activation of gases and reaction products. CONSTITUTION:The inside of a vacuum chamber 1 is maintained at a prescribed vacuum degree and a substrate 3 is heated to about 300 deg.C. Gaseous nitrogen and gaseous argon are respectively introduced from gas introducing pipes 15, 17. A CO2 laser 4 is started in this state to generate a high-output laser beam and sputtering is executed by condensing this beam onto a target 7. Microwaves are simultaneously generated by operating an ECR microwave ion source 13 and a current is passed to an electromagnet 9 to generate plasma. Further, about 25OV voltage is impressed between an electrode 6 and the substrate 3 to generate plasma near the substrate 3. As a result, the sputtered particles from the target 7 are generated on the substrate 3 and the reaction product on the substrate 3 is activated by the generation of the plasma, by which the good-quality thin film is formed at a low temp. on the substrate 3.

Description

Detailed Description of the Invention

[0001]

The present invention is suitable for forming a good quality thin film on a substrate by using a laser and an electron cyclotron resonance microwave ion source, an RF plasma apparatus, an ion beam apparatus, a radical ion beam apparatus, or the like. The present invention relates to a thin film forming apparatus.

[0002]

2. Description of the Related Art Conventionally, a laser sputtering method in which a high-power laser beam is focused on a target and sputtered particles are deposited on a substrate to form a thin film is well known. Also,
CVD (Chemical Vapor Dep) using an electron cyclotron resonance (ECR) microwave ion source
and the DC plasma CVD method and the like are already well known.

[0003]

When the film is formed by the laser sputtering method, the film is formed by irradiating the target with high-power laser light and sputtering. However, in this method, the activation rate and ionization rate are relatively low, and the production rate of the reaction product is not so high, so that it is difficult to control the composition. In addition, a CVD method using an ECR microwave, an RF plasma CVD method or a DC plasma C
The VD method alone does not form a good quality thin film because the types of films to be synthesized are limited and the ionization rate does not increase so much.

As an example of the conventional example, an example in which an AlN film is formed is described in the proceedings of the 52nd Japan Society of Applied Physics, 413 (199)
1 year), the film deposition rate was about 340 A (angstrom) in 10 minutes. The electromechanical coupling coefficient is only 10% or less as a conventional value.

An object of the present invention is to use a laser sputtering method and an EC.
By combining the R microwave CVD method or the RF plasma CVD method with another CVD method such as the DC plasma CVD method, the activation of the gas or the reactant is promoted, and the film can be formed at a high speed and a high quality thin film can be formed. It is to provide a thin film forming apparatus.

[0006]

In order to achieve the above object, the present invention provides a thin film forming apparatus for forming a thin film on a substrate in a vacuum chamber by sputtered particles produced by focusing and irradiating a laser with a target. And the substrate is held to generate a local plasma by combining with the electrode in a gas atmosphere,
A thin film forming apparatus is provided in which an electron cyclotron resonance microwave ion source for irradiating ions and radicals is arranged on the substrate in a vacuum chamber facing the thin film forming surface of the substrate.

Alternatively, the second aspect of the present invention is a thin film forming apparatus for forming a thin film on a substrate in a vacuum chamber by sputtering particles produced by focusing and irradiating a laser with a target, wherein the substrate is a gas. An RF plasma generation source for irradiating the substrate with ions and radicals is arranged in a vacuum chamber that is held to generate local plasma in combination with an electrode in an atmosphere and faces the thin film formation surface of the substrate. And a thin film forming apparatus.

A third invention of the present invention is a thin film forming apparatus for forming a thin film on a substrate in a vacuum chamber by means of sputtered particles produced by focusing and irradiating a laser on a target, the thin film forming surface of the substrate. A thin film forming apparatus characterized in that an RF plasma generator for irradiating ions and a radical beam generator for irradiating radicals are arranged on the substrate in a vacuum chamber facing each other.

A fourth invention of the present invention is a thin film forming apparatus for forming a thin film on a substrate in a vacuum chamber by means of sputtered particles produced by focusing and irradiating a laser with a target, the thin film forming surface of the substrate. The thin film forming apparatus is characterized in that an ion generator for irradiating ions and a radical beam generator for irradiating radicals are arranged on the substrate in a vacuum chamber facing each other.

[0010]

As in the present invention, the reaction product sputtered by the high-power laser beam is irradiated with the ions and radicals generated from the ECR microwave ion source or the RF plasma generation source arranged above the substrate, and the substrate The activation of the reaction product can be further enhanced by generating plasma between the electrode and the substrate provided around the substrate. As a result, a thin film can be formed with good quality and at high speed.

Alternatively, the activation of the reaction product can be enhanced by simultaneously irradiating the substrate with the ions generated from the RF plasma or the ions from the ion beam generator and the radicals from the radical beam generator. Thereby, a thin film can be formed with good quality and at high speed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an apparatus according to an embodiment of the present invention.
The vacuum chamber 1 of the apparatus has a substrate holder 2 with a heater inside.
Are provided to support the substrate 3. The substrate holder 2 is heated by the heater power source 19 to heat the substrate 3. Further, an electrode 6 to which a gas introduction pipe 17 is connected is installed around the substrate 3, and the substrate 3 and the electrode 6 are connected by a DC power supply 18. A carbon dioxide gas laser 4 which is a high-power laser is provided outside the vacuum chamber 1, and a concave mirror 5 is set to focus the laser light on a target 7 in the vacuum chamber 1.
Laser light is introduced into the vacuum chamber 1 through the KBr window 8 attached to. A shutter 21 is arranged on the substrate 3 side of the target 7. Further, the ECR plasma generation chamber 10 of the ECR microwave ion source is installed above. In addition, 9 is an electromagnet, 11 is a quartz window for introducing microwaves, 12 is a microwave waveguide, 13 is a microwave generation source, 14 is a valve, and 15 is a gas introducing pipe. These are the ECR microwave ions. It is a component of the source. A shutter 20 is arranged on the substrate 3 side of the ECR microwave ion source.

Next, the AlN thin film according to this embodiment will be specifically described. First, the vacuum chamber 1 1 × 10 using a diffusion pump or a turbo pump and an oil rotary pump (both not shown.) ^- evacuated to ⁷ Torr or less. The substrate 3 is heated to about 300 ° C. Next, the valves 14 and 16 are opened to introduce gas, and ammonia or nitrogen gas and argon gas are introduced, respectively. Shutters 20, 2
Keep 1 closed. In this state, the carbon dioxide gas laser is activated to generate a high-power laser beam, which is focused on an Al or AlN target for sputtering. Furthermore, at the same time E
The CR microwave ion source is operated to generate microwaves, and a current is passed through the electromagnet 9 to generate plasma. Further, a voltage of about 250 V is applied between the electrode 6 and the substrate 3 to generate plasma near the substrate 3. After the above conditions are stabilized, the shutters 20 and 21 are simultaneously opened. As described above, the sputtered particles from the target 7 are generated on the substrate 3, and the reaction products on the substrate 3 are activated by the irradiation of ions and radicals from the ECR microwave ion source and the generation of plasma between the substrate 3 and the electrode 6. And a good quality thin film is formed at low temperature.

In this example, a film was formed on the silicon substrate for about 10 minutes in this state. The film thickness of the AlN film thus formed was about 1 μm. When the film was subjected to X-ray diffraction analysis, it was a hexagonal crystal and a c-axis oriented film. An epitaxial film was obtained when synthesized on a sapphire substrate heated to about 300 ° C. The electromechanical coupling coefficient of this film was measured and found to be about 17.5%. This value is equal to or higher than that of a film synthesized by a normal sputtering device. Further, the composition of the thin film was measured with an X-ray microanalyzer, and it was about 1: 1.

As described above, it is understood that the present invention makes it possible to obtain a good quality thin film at a low temperature. Of course, if the gas is nitrogen and the target is boron (B) with this device, B
N can be synthesized, methane as gas, T as target
Needless to say, a carbide such as TiC can be synthesized if i is used.

An embodiment of the second invention of the present invention will be described below with reference to the drawings. FIG. 2 is a diagram showing an apparatus according to an embodiment of the present invention. A substrate holder 2 with a heater is provided inside a vacuum chamber 1 of the apparatus to support a substrate 3. The substrate holder 2 is heated by the heater power source 19 to heat the substrate 3. Further, an electrode 6 to which a gas introduction pipe 17 is connected is installed around the substrate 3, and the substrate 3 and the electrode 6 are connected by a DC power supply 18. A carbon dioxide laser 4, which is a high-power laser, is provided outside the vacuum chamber 1, and a concave mirror 5 is set to focus the laser light on a target 7 in the vacuum chamber 1 and a KBr window attached to the vacuum chamber 1. Laser light is introduced into the vacuum chamber 1 through 8. A shutter 21 is arranged on the substrate 3 side of the target 7. Further upward, an RF plasma generation coil 22 of the RF plasma generation source is provided.
Is installed. Reference numeral 23 is an RF generator, 14 is a valve, and 15 is a gas introduction pipe, which are constituent elements of the RF plasma generation source. A shutter 20 is arranged on the substrate 3 side of the RF plasma generation source.

Next, the AlN thin film according to this embodiment will be specifically described. First, the vacuum chamber 1 1 × 10 using a diffusion pump or a turbo pump and an oil rotary pump (both not shown.) ^- evacuated to ⁷ Torr or less. The substrate 3 is heated to about 300 ° C. Next, the valves 14 and 16 are opened to introduce gas, and ammonia or nitrogen gas and argon gas are introduced, respectively. Shutter 20,
21 is closed. In this state, the carbon dioxide gas laser is activated to generate a high-power laser beam, which is focused on the Al or AlN target 7 and sputtered. Further, at the same time, RF is generated to generate plasma. Further, a voltage of about 250 V is applied between the electrode 6 and the substrate 3 to generate plasma near the substrate 3. After the above conditions are stabilized, the shutters 20 and 21 are simultaneously opened. As described above, the sputtered particles from the target 7 are generated on the substrate 3, and the reaction products on the substrate 3 are activated by the irradiation of ions and radicals from the RF plasma generation source and the generation of plasma between the substrate 3 and the electrode 6. As a result, a good quality thin film is formed at a low temperature.

In this example, a film was formed on the silicon substrate for about 10 minutes in this state. The film thickness of the AlN film thus formed was about 1 μm. When the film was subjected to X-ray diffraction analysis, it was a hexagonal crystal and a c-axis oriented film. An epitaxial film was obtained when synthesized on a fire substrate heated to about 300 ° C. The electromechanical coupling coefficient of this film was measured and found to be about 17.5%. This value is equal to or higher than that of a film synthesized by a normal sputtering device. Further, the composition of the thin film was measured with an X-ray microanalyzer, and it was about 1: 1.

As described above, it can be seen that the present invention makes it possible to obtain a good quality thin film at a low temperature. Of course, if the gas is nitrogen and the target is boron (B) with this device, B
It goes without saying that N can be synthesized, an oxide such as ZnO can be synthesized if oxygen is used as the gas and Zn is used as the target, and a carbide such as TiC can be synthesized if methane is used as the gas and Ti is used as the target.

The third embodiment of the present invention will be described below. FIG. 3 is a diagram showing an apparatus according to an embodiment of the present invention.
A substrate holder 2 with a heater 32 is provided inside a vacuum chamber 1 of the apparatus to support a substrate 3. A carbon dioxide laser 4, which is a high-power laser, is provided outside the vacuum chamber, and a lens 3
At 3, the laser light is set to be focused on the target 7 in the vacuum chamber 1, and the light is introduced into the vacuum chamber through the KBr window 8 attached to the vacuum chamber 1. Gas is introduced from the gas introduction tube 15 and high frequency is generated in the RF coil 22 to generate plasma inside the quartz tube 34 and irradiate the substrate 3. Further, the substrate 3 is irradiated with radicals generated by the radical beam generator 35.

A case where an AlN thin film is formed by this apparatus will be specifically described. First, use a diffusion pump or a turbo pump and an oil rotary pump to create a vacuum chamber 1.
Evacuated to ⁷ Torr or less ^- the inner 1 × 10. Set the substrate to about 300 ° C, then valve 1 to introduce gas
Open 4 and 16, and introduce argon gas and ammonia or nitrogen gas, respectively. The shutter 31 is closed.
In this state, the carbon dioxide gas laser 4 is activated to generate high-power laser light, which is focused on the Al or AlN target 7 and sputtered. RF plasma is generated by the coil 22, and the radical beam power source is also set to generate radicals. After the state is stabilized, the shutter 31 is opened and the film is grown.

In this example, a film was formed on the silicon substrate in this state for about 10 minutes. The film thickness of the AlN film thus formed was about 1 μm. When the film was subjected to X-ray diffraction analysis, it was a hexagonal crystal and a c-axis oriented film. An epitaxial film was obtained when synthesized on a sapphire substrate heated to about 300 ° C.

When the electromechanical coupling coefficient of this film was measured, a value of about 17.5% was obtained. This value is usually more than the value of the film synthesized by the sputtering apparatus. Further, the composition of the thin film was measured with an X-ray microanalyzer and was about 1: 1.

As described above, it is understood that the present invention makes it possible to obtain a good quality thin film at a low temperature. Of course, with this apparatus, BN can be synthesized if the gas is nitrogen or ammonia and the target is boron (B), and oxides such as ZnO can be synthesized if the gas is oxygen and the target is Zn. Needless to say, a carbide such as TiC can be synthesized if the target is Ti.

The fourth embodiment of the present invention will be described below. FIG. 4 is a diagram showing an apparatus according to an embodiment of the present invention.
A substrate holder 2 with a heater 32 is provided inside a vacuum chamber 1 of the apparatus to support a substrate 3. Gas introduction pipe 49
Gas is introduced to generate ions from the ion beam generator 47 and irradiate them on the substrate 3, and at the same time, the radical beam generator A41 and the radical beam generator B are provided above the substrate.
Radicals from 44 are irradiated onto the substrate, and laser light from a laser 4 installed outside the vacuum chamber 1 is further applied to the lens 3
At 3, the target 7 is focused through the window 8 so that the target material can be emitted onto the substrate. In addition, 4 in the figure
8 is an ion beam power source, 42, 46 and 50 are valves,
43 and 45 are gas introduction pipes, 19 heater power supply, and 31 is a shutter.

A case where an AlN thin film is formed by this apparatus will be specifically described. First, use a diffusion pump or a turbo pump and an oil rotary pump to create a vacuum chamber 1.
Evacuated to ⁷ Torr or less ^- the inner 1 × 10. Set the substrate to about 300 ° C and then valve 4 to introduce gas.
2, 46 are opened and ammonia or nitrogen gas is introduced. Further, the valve 50 is opened to introduce argon gas. In this state, the carbon dioxide gas laser 4 is activated to generate high-power laser light, which is focused on the Al or AlN target 7 to perform sputtering. The ion beam generator 47 is activated, and at the same time the radical beam generator A41,
After setting the power source of B44 to a predetermined condition, when the state is stable, the shutter 31 is opened to grow a film on the substrate 3.

In this example, a film was formed on the silicon substrate for about 10 minutes in this state. The film thickness of the AlN film thus formed was about 1 μm. X of formed film
When the line diffraction analysis was performed, it was a hexagonal crystal and a c-axis oriented film. An epitaxial film was obtained when synthesized on a sapphire substrate heated to about 300 ° C.

When the electromechanical coupling coefficient of this film was measured, a value of 17.5% was obtained. This value is equal to or higher than that of a film synthesized by a normal sputtering device. The composition of the film was measured with an X-ray microanalyzer and was found to be approximately 1: 1.

As described above, it is understood that the present invention makes it possible to obtain a good quality thin film at a relatively low temperature. Of course, it is needless to say that an oxide film, a nitride film, a carbide film and the like can be synthesized by changing the target material and the type of gas in this apparatus.

[0030]

As described above, according to the present invention,
The reaction product produced by the high-power laser light is irradiated with ions and radicals generated from the ECR microwave ion source or RF plasma generation source on the substrate from above, and between the electrode and the substrate arranged around the substrate. By applying a voltage to generate plasma, the activation of the reaction product can be enhanced, and a good quality thin film can be formed at a relatively low temperature. As a result, applications such as functional dielectric films and semiconductor films become possible.

Further, by using ions generated by RF plasma or ions generated by an ion generator and radicals to enhance the activation of the reaction product,
A good quality film can be formed at a relatively low temperature with good reproducibility and controllability. Further, by using a plurality of ion beams or radical beams depending on the type of film to be formed and changing the types and proportions of the ions or radicals and optimizing, it is possible to further expand the quality and application range.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an overall structure of a thin film forming apparatus according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the overall structure of a thin film forming apparatus according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view showing the overall structure of a thin film forming apparatus according to an embodiment of the present invention.

FIG. 4 is a sectional view showing the overall structure of a thin film forming apparatus according to an embodiment of the present invention.

[Explanation of symbols]

 1 Vacuum Tank 2 Substrate Holder 3 Substrate 4 Carbon Dioxide Laser 5 Concave Mirror 6 Electrode 7 Target 8 KBr Window 9 Electromagnet 10 ECR Plasma Generation Chamber 11 Quartz Window 12 Waveguide 13 Microwave Source 14 Valve 15 Gas Inlet 16 16 Valve 17 Gas Introducing tube 18 DC power supply 19 Heater power supply 20, 21 Shutter 22 Coil 23 RF generator 31 Shutter 32 Heater 33 Lens 34 Quartz tube 35 Radical beam generator 41 Radical beam generator A 44 Radical beam generator B 42, 45, 49 Gas introduction pipe 43,46,50 Valve 47 Ion beam generator 48 Power supply

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H01L 21/318 B 7352-4M // C23C 16/50 7325-4K

Claims (4)

[Claims] 1. A thin film forming apparatus for forming a thin film on a substrate in a vacuum chamber by means of sputtered particles produced by focusing and irradiating a laser with a target, wherein the substrate is bonded to an electrode in a gas atmosphere. An electron cyclotron resonance microwave ion source for irradiating the substrate with ions and radicals is arranged in a vacuum chamber which is held so as to generate a local plasma and faces the thin film formation surface of the substrate. Thin film forming equipment. 2. A thin film forming apparatus for forming a thin film on a substrate in a vacuum chamber by sputtered particles produced by focusing and irradiating a laser with a target, wherein the substrate is bonded to an electrode in a gas atmosphere. A thin film forming apparatus, wherein an RF plasma generation source for irradiating the substrate with ions and radicals is arranged in a vacuum chamber which is held so as to generate local plasma by facing the thin film forming surface of the substrate. .. 3. A thin film forming apparatus for forming a thin film on a substrate in a vacuum chamber by means of sputtered particles produced by converging and irradiating a target with a laser, the vacuum chamber facing a thin film forming surface of the substrate. A thin film forming apparatus, wherein an RF plasma generator for irradiating ions and a radical beam generator for irradiating radicals are arranged on the substrate. 4. A thin film forming apparatus for forming a thin film on a substrate in a vacuum chamber by means of sputtered particles produced by converging and irradiating a target with a laser, the vacuum chamber facing the thin film forming surface of the substrate. A thin film forming apparatus, wherein an ion generator for irradiating ions and a radical beam generator for irradiating radicals are arranged on the substrate.