KR0153568B1 - Apparatus and method of fabricating wide area thin film using pulse laser - Google Patents

Abstract

An apparatus and method for producing a large area thin film using a pulse laser are disclosed. The large-area thin film production apparatus of the present invention comprises a vacuum tank; A rotatable target holder installed at one side in the vacuum chamber; A target attached to the target holder; A reaction gas injector for injecting a reaction gas into the vacuum chamber; A pulse laser installed outside the vacuum chamber to deliver a high energy laser beam to the target to form a plum, which is a mixture of ions, atoms, molecules and electrons; An optical system for irradiating a target surface through the laser beam; A stage installed at the lower end of the vacuum chamber and driven simultaneously in rotation, front, rear, left and right; A substrate detachably installed on the stage and interlocked with the stage; And it is composed of a shutter which is provided insulated in the upper half of the substrate and the opening can be adjusted. The formed plume grows on the substrate with only a portion of the plume selectively passing through the shutter by opening only a specific section of the shutter, wherein the substrate is driven in a rotational, forward, backward, left-right direction so that the plum grown on the substrate rapidly It can solidify to form a homogeneous thin film.

Description

Apparatus and method for manufacturing large area thin film using pulse laser

The present invention relates to an apparatus and method for depositing a large area thin film using a pulse laser, and more particularly, to a device for producing a diamond-like thin film emitter having a large area having uniform electron emission characteristics and mechanical properties using a pulse laser. And to a method.

In general, diamond-like carbon thin films exhibit high electron emission characteristics even under low electric fields, and thus are suitable for use as emitter materials for field emission display devices. Conventional methods for obtaining such diamond-like carbon thin film include a method using filament thermal energy or microwave plasma, Plasma Chemical Vapor Deposition Method (CVD method) using radio-frequency (RF), There is a sputtering method (RF sputtering method), a pulsed laser deposition method using a high frequency. However, in order to obtain a high quality diamond-like carbon thin film using filament thermal energy or microwave plasma, it is essential to maintain the temperature of the substrate at several hundred degrees Celsius to 1000 degrees Celsius.

Therefore, in the case of a material such as glass whose melting point of the substrate material to be used is lower than the substrate temperature range, the thermal energy of the filament or the microwave plasma method cannot be used. In addition, the filament thermal energy or microwave plasma method cannot be used. In addition, since the filament thermal energy or microwave plasma method is a high temperature process, there are many problems in terms of process time and energy efficiency during mass production.

On the other hand, it is possible to produce an amorphous diamond-like carbon thin film at room temperature by RF plasma CVD method, but the thin film manufactured by the above method tends to be peeled off between the substrate and the thin film depending on the substrate used due to the high residual stress. There is this.

In addition, it is possible to produce a diamond-like carbon thin film at room temperature by the RF sputtering method, but the thin film prepared by this method has a problem that it is difficult to obtain a high quality diamond-like carbon thin film compared to the RF plasma CVD method.

The manufacturing method of the pulsed laser deposition method is simpler than the conventional diamond-like carbon thin film manufacturing method mentioned above, and it is possible to manufacture a high quality diamond-like carbon thin film with a high ratio of a diamond bond component.

However, the pulsed laser deposition method has a problem that it is difficult to produce a large diamond-like carbon thin film compared to the diamond-like carbon thin film manufacturing method described above. That is, a plum formed by irradiating a high energy laser to a target is a mixture of ions, atoms, molecules, and electrons, and is formed only in a small area in a direction perpendicular to the target plane.

Therefore, the thickness of the diamond-like thin film formed on the target surface shows a serious difference as the plume leaves the small area formed, and in particular, in the case of using a multi-component alloy target, the proportion of the diamond phase formed in addition to the severe thickness difference There is a problem that greatly differs depending on the position of the plum formation.

Therefore, in the above-described conventional method, when manufacturing a diamond-like carbon thin film while fixing or simply rotating a substrate, the homogeneous thin film having a uniform thickness, film composition ratio, electrical and mechanical properties, etc., is about 1 inch or more. There was a problem that is almost impossible to manufacture.

Accordingly, the present invention has been made to solve the above-described conventional problems, the first object of the present invention is to form a thin film and uniform thickness over the entire area of the substrate using a pulse laser and a shutter (Shutter) It is an object of the present invention to provide a device for producing a large-diameter diamond-like carbon thin film having a uniform composition ratio or electrical and mechanical properties depending on the position.

In addition, a second object of the present invention is to provide a method for producing a large area thin film using the apparatus for producing a large area thin film using the above-described pulse laser.

1 is a schematic configuration diagram of a pulse laser deposition apparatus for depositing a large area of diamond-like carbon thin film using the pulse laser of the present invention.

* Explanation of symbols for main parts of the drawings

1 pulse laser 2 optical system

3: Target 4: Target Holder

5: Plume 6: Shutter

7: reaction gas injection unit 8: substrate

9: X-Y stage 10: rotating plate

11: vacuum pump 12: vacuum chamber

13: stage

In order to realize the first object of the present invention described above, the present invention is a vacuum chamber;

A rotatable target holder installed at one side in the vacuum chamber;

A target attached to the target holder;

A reaction gas injector for injecting a reaction gas into the vacuum chamber;

A pulse laser installed outside the vacuum chamber to deliver a high energy laser beam to the target to form a plum, which is a mixture of ions, atoms, molecules and electrons;

An optical system for irradiating a target surface through the laser beam;

A stage installed at the lower end of the vacuum chamber and driven simultaneously in rotation, front, rear, left and right;

A substrate detachably installed on the stage and interlocked with the stage; And

Provided is an apparatus for manufacturing a large-area thin film using a pulsed laser including a shutter that is isolated from the upper half of the substrate and the shutter can be adjusted.

In addition, in order to realize the second object of the present invention,

(i) detachably mounting the substrate on a stage installed at the lower end of the vacuum chamber and driven simultaneously in rotation, front, rear, left and right;

(ii) injecting a reaction gas into the vacuum chamber through a reaction gas inlet;

(iii) adjusting the opening of the shutter;

(iv) irradiating a laser beam onto a surface of a target attached to a rotatable target holder provided at one side of the vacuum chamber by using a pulse laser installed outside the vacuum chamber to emit a laser beam, thereby causing ions, atoms, molecules And generating a plum that is a mixture of electrons; And

(v) fabricating a large area thin film using a pulse laser, comprising: forming a uniform thin film on the substrate over a large area by driving the stage in rotation, forward, backward, left, and right; Provide a method.

According to the large-area thin film manufacturing apparatus and method using the pulse laser of the present invention, when the plum generated by the irradiation of the high-energy laser beam is grown on the substrate, the substrate is rotated and driven at the same time The thin film layer can be made homogeneous, and the shutter can be configured to grow a uniform diamond-like thin film so that the size of the laser plum can be kept constant, so that the thin film layer can be grown in a homogeneous state.

In addition, the diamond-like carbon thin film produced by the above-described large-area thin film manufacturing apparatus and method using the pulse laser of the present invention is used for the production of emitters for field emission display devices (FEDs), thereby providing a large-area electric field. Emitters for emitting display elements can be manufactured.

Hereinafter, with reference to the accompanying drawings, it will be described in detail the present invention through an embodiment of the present invention.

1 is a schematic configuration diagram of a pulse laser deposition apparatus for depositing a large area of diamond-like carbon thin film using the pulse laser of the present invention.

Referring to FIG. 1, a rotatable target holder 4 is provided inside the vacuum chamber 12, and a target 3 for forming a plume 5 is attached to the target holder 4. .

One side portion of the vacuum chamber 12 is provided with a reaction gas injection unit 7 for adding impurities to the diamond-like carbon thin film.

Moreover, the stage 13 which rotates, drives back, front, left and right, is provided in the lower end part in the said vacuum chamber 12. As shown in FIG. In more detail, the rotatable rotating plate 10 is provided, and the X-Y stage 9 capable of front, rear, left and right movements is fixed on the rotating plate 10.

In addition, a substrate 8 for cooling the plume 5 to form a thin film is positioned on the XY stage 9, and a shutter 6 is provided at an upper half of the surface of the substrate 8 to adjust the opening area. have. At this time, the role of the shutter is to uniformly deposit the thin film over a large area. The laser beam hitting the target is converted into a plume and moved toward the substrate, but the vertical distance is the shortest distance between the plume and the substrate. The thickness of the grown layer is formed thicker in the portion, and the thickness of the formed layer becomes thinner as it moves from the vertical portion to the peripheral portion, so that the thickness of the grown thin film layer can be adjusted by adjusting the window of the shutter in advance to prevent this.

First, the valve of the gas injection unit 7 is opened to inject the reaction gas into the vacuum chamber 12 to add impurities.

Hydrogen may be used as one of the reaction gases used in the present invention. The target used in the present invention may be a graphite target or a transition metal-containing carbon target made of an alloy of a transition metal such as chromium (Cr), molybdenum (Mo), tungsten (W), titanium (Ti) and carbon.

Compared with the case of simply using the graphite target, the use of the transition metal-containing carbon target yields a diamond-like carbon thin film containing the transition metal, and the thin film is controlled by controlling the electron emission characteristics or the electrical resistance by controlling the transition metal content. It is much easier and also has the advantage that the adhesion to the substrate is improved.

In addition, the pulse laser 1 and the optical system 2 are provided outside the vacuum chamber 12, and the pulse laser 1 generates a laser beam. The laser beam generated by the pulsed laser 1 passes through the optical system 2 and is irradiated onto the surface of the target 3 in the vacuum chamber 12.

The laser beam transmitted on the surface of the target 3 is a beam having a high energy density, and exchanges energy by collision with the target surface. As a result, various kinds of ions, atoms, molecules, electrons, and the like are released from the surface of the target 3, and thus a plum 5, which is a mixture thereof, is formed in the vacuum chamber 12.

The plume 5 formed in this way moves in the vacuum chamber 12 towards the substrate 8, impinges upon the substrate 8 and is deposited over the entire area on the substrate 8. At this time, opening only a specific portion of the shutter 6 provided in the upper half of the surface of the substrate 8 allows only a portion of the very homogeneous plum to selectively pass through the shutter.

The plum which has passed in this way is continuously grown over a large area on the substrate 8 fixed to the X-Y stage 9 which moves back and forth, left and right, attached to the rotating plate which rotates. The grown plume solidifies rapidly, forming a continuous large area thin film on the substrate 8.

The thin film formed by the above-described method is uniformly formed in the entire area of the substrate since the substrate is moved back and forth, left and right, and rotationally. In addition, the plume passing through the limited opening of the shutter exhibits a much more homogeneous state than without the shutter.

The position and size of the laser plume are always fixed constantly, and during the thin film growth, if the substrate is moved back, forth, left and right with rotation by the rotating plate and the X-Y stage, it is possible to grow a uniform thin film in a large area of a desired size.

In another embodiment of the present invention, the stage 13 may be replaced by a configuration of the X-Y stage 9 and the rotating plate 10 to which the rotating plate 10 is attached on the X-Y stage 9. Also in this case, the same effects as the effects of the present invention can be obtained.

As described above, according to the present invention, a diamond-like carbon thin film manufactured by using a pulse laser has a homogeneous distribution of composition ratios depending on the thickness of the thin film and the formation position of the thin film over its entire area. I can keep it.

As described above, the diamond-like carbon thin film manufactured by using the pulse laser according to the present invention, since the substrate is rotated and the front and rear, left and right movement by the operation of the rotating plate and the XY stage driven in front and rear, The composition ratio according to the thickness of the thin film and the formation position of the thin film is uniformly distributed over the entire area, and the electrical and mechanical properties can also be realized homogeneously.

In addition, since the shutter is configured to grow a uniform diamond-like thin film, the size of the laser plume can be kept constant by the shutter hole located on the substrate, thus showing a much more homogeneous state than when the shutter is not used.

In addition, by using the diamond-like carbon thin film produced according to the present invention in the manufacture of an emitter for a field emission display device, an emitter for a large area field emission display device can be provided.

Although described above with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below I can understand that you can.

Claims (8)

A vacuum chamber 12; A rotatable target holder (4) installed at one side in the vacuum chamber (12); A target (3) attached to the target holder (4); A reaction gas injector 7 for injecting a reaction gas into the vacuum chamber 12; A pulsed laser (1) installed outside the vacuum chamber (12) for delivering a high energy laser beam to the target (3) to form a plum (5), which is a mixture of ions, atoms, molecules, and electrons; An optical system (2) for passing the laser beam and irradiating it onto a target (3) surface; A stage 13 installed at the lower end of the vacuum chamber 12 and simultaneously driven in rotation, front, rear, left and right; A substrate (8) detachably mounted on the stage (13) and interlocked with the stage (13); And a shutter (6) isolated from the upper half of the substrate (8) to adjust the opening. According to claim 1, wherein the stage (13) is provided on one side of the vacuum chamber 12, the rotating plate (10) capable of rotating movement; And an X-Y stage (9) installed on the rotating plate (10) and capable of forward, backward, and left and right movements. The apparatus of claim 1, wherein the target is a graphite target, and the thin film is a diamond-like carbon thin film. The apparatus of claim 3, wherein the reaction gas is hydrogen, and the thin film is a hydrogen-containing diamond-like carbon thin film. The apparatus of claim 1, wherein the target is an alloy target of carbon and a transition metal, and the thin film is a transition metal-containing diamond-like carbon thin film. The apparatus of claim 5, wherein the reaction gas is hydrogen, and the thin film is hydrogen and a transition metal-containing diamond-like carbon thin film. (i) detachably mounting the substrate 8 to the stage 13 installed at the lower end of the vacuum chamber 12 and simultaneously driven in rotation, front, rear, left and right; (ii) injecting a reaction gas into the vacuum chamber 12 through a reaction gas injector 7; (iii) adjusting the opening of the shutter 6; (iv) a target (3) attached to a rotatable target holder (4) installed at one side of the vacuum chamber (12) using a pulse laser (1) installed outside the vacuum chamber (12) to emit a laser beam; Irradiating a laser beam on the surface of c) to produce a plum 5 which is a mixture of ions, atoms, molecules and electrons; And (v) forming the plume generated in step (iv) over the substrate 8 over a large area by rotating the stage 13 in front, rear, left, and right directions. The manufacturing method of a large area thin film using the pulse laser made into. The field emitter for field emission display device is composed of the homogeneous thin film manufactured by the manufacturing apparatus of claim 1, wherein the area of the field emitter for field emission display device is large. Field emitters for area field emission display devices.