KR100376932B1 - Optical equipment for thin film deposition by laser ablation method - Google Patents

Abstract

The present invention provides a substrate (8) installed in the inner center of the vacuum chamber (4), a substrate heater (7) embedded in the lower substrate and a laser plume (6) for forming a thin film on the substrate, and the laser plume And a laser source for generating a laser beam 2 formed at a target 5 irradiated onto the surface by a laser beam, a support for supporting the target 5, and a lower end of the vacuum chamber 4. 1), a condenser lens 3 for condensing a laser beam from the laser source, a drive reflector 10 for reflecting the condensed laser beam, and a vacuum pump formed on one side thereof, The laser beam 2 is irradiated onto the fixed target surface by slowly driving or rotating the driving reflector 10 that can adjust the reflecting surface tilt installed outside the vacuum chamber 4 to the fixed target surface, so that the laser spot on the surface of the target 5 Ruled circle, ellipse, upright The crosshairs, etc., so that the target 5 itself can be effectively rotated, so that the target driving motor is not necessary, so that the structure of the vacuum chamber 4 can be simplified, and the target 5 Thin films, such as thin film devices by the laser ablation method, characterized in that the ejection position of the laser plume 6 is changed from the surface at a time, so that the thin film formed on the substrate 8 is formed in a uniform thickness over a large area. It relates to a formation method.

Description

Optical equipment for thin film deposition by laser ablation method}

The present invention relates to a thin film forming apparatus and method such as a thin film device by a pulsed laser ablation method. More specifically, when a thin film such as a thin film device is formed on a substrate by the laser ablation method of the present invention, a reflector, which is an optical device installed outside the vacuum chamber, is rotated at a low speed or in a straight line to irradiate a fixed target surface to irradiate the laser. The present invention relates to an apparatus and method for forming a thin film such as a thin film device on a substrate while allowing the spot (pleum) to be a circle, an ellipse, a straight line or the like.

FIG. 1 is a schematic view showing a process of forming a thin film such as a thin film device by a conventional laser ablation method. As shown in FIG. 1, in a conventional laser ablation method, an excimer (EXIMER) or a yag (YAG) is shown. ) The laser beam 2 generated from a laser generating source such as the laser 1 is condensed by the lens 3 and irradiated onto the surface of the target 5 in the vacuum chamber 4, and the target is irradiated by the laser beam 2. (5) Particles protruding in a direction perpendicular to the surface (plasma-shaped laser plume 6) form a thin film on the substrate 8 located above the substrate heater 7.

However, in the conventional method of forming a thin film on a substrate using the laser ablation method described above, when a laser beam generated from a laser generation source is irradiated to a target, small holes are formed on the surface thereof, and when it is exposed for a long time, The depth is deepened, resulting in a sharp decrease in laser ablation efficiency from the target surface. In order to prevent such a decrease in efficiency, the target must be rotated at a low speed using an electric motor to form a thin film. In this case, as shown in FIG. 1, in order to rotate the target, the target was rotated by placing a driving motor inside or outside the vacuum chamber. In the former case, it is necessary to secure a space for installing a target driving motor inside the vacuum chamber, so the space to extract the vacuum with a vacuum pump may become large or complicated, and the disadvantages and pollution sources of opening the vacuum chamber for troubleshooting In the latter case, there was a drawback in that the driving force of the electric motor was transferred from the outside of the chamber to the inside without breaking the vacuum. Due to these technical disadvantages, the structure is complicated and the vacuum space is large, the vacuum pumping time after the sample replacement or repair takes a lot of time. In particular, in the conventional configuration, since the ejection position of the laser plume is constant with respect to the substrate surface, the thickness of the thin film formed on the substrate becomes thick at the center of the laser plume, so that the area capable of forming a thin film having a uniform thickness is small. Had a big problem.

As a result, the present invention has been devised to solve the above-mentioned conventional problems, and an object of the present invention is to form a thin film such as a thin film device on a substrate by a laser ablation method, and the slope of the reflection surface installed outside the vacuum chamber. While driving an optical device called a driving reflector designed to be adjusted slowly or in a straight line, the laser beam is irradiated to the fixed target surface so that the rule of the laser spot on the target surface becomes circular, ellipse, straight line, cross, etc. By allowing the target to rotate itself, the target driving motor is not required, and the structure of the vacuum chamber can be simplified, and the thin film formed on the substrate by changing the ejection position of the laser plume from the target surface every time. Over a large area, thin films can be formed with uniform thickness To provide a film forming apparatus and method, such as film device is the object of the present invention.

1 is a schematic view of a thin film formation process by a conventional laser ablation method

Figure 2 is a schematic diagram of a thin film formation process by the laser ablation method of the present invention

Figure 3a is a case where the tilt angle of the reflecting surface of the geometrical optical detail reflector for the theoretical proof of the present invention is 0 (same as the conventional method)

Figure 3b is the reflection plane tilt angle of the geometric optical detail reflector for the theoretical proof of the present invention is θ

Figure 4 is a detailed view of the driven reflector of the present invention

Explanation of symbols for the main parts of the drawings.

1: laser source 2: laser beam

3: condenser lens 4: vacuum chamber

5: target 6: laser plume

7: substrate heater 8: substrate

9: target rotating motor 10: driving reflector

10a: Reflective surface of driven reflector at negative (-) slope

10b: Reflective surface of driven reflector at positive (+) slope

10c: Protractor 10d: Screw for fixing the reflecting mirror

10e: reflecting mirror 10f: angle adjusting screw

10 g: drive shaft θ: inclination angle of the reflecting surface (°)

In order to achieve the above object, the present invention is a fixed target surface of the laser beam 2 while driving the drive-type reflector 10, which can adjust the tilt of the reflection surface installed outside the vacuum chamber 4 in a rotational or straight line Irradiated on the surface of the laser spot on the surface of the target 5 to form a circle, an ellipse, a straight line, a cross, or the like, so that the effect of the target 5 itself being rotated can be obtained. Therefore, the structure of the vacuum chamber 4 can be simplified, and the ejection position of the laser plume 6 is changed from the surface of the target 5 at a time, so that the thin film formed on the substrate 8 is uniform over a large area. A thin film forming method such as a thin film device by a laser ablation method characterized by forming a thin film with a thickness.

Hereinafter, a method of forming a thin film, such as a thin film device, by a laser ablation method according to a preferred embodiment of the present invention will be described in detail. EXAMPLES An ultrasonic cleaner is used to clean a surface of an object (such as Si or Ni) to form a thin film using alcohol or acetone. After about 30 minutes of washing, and holding the object holder in the vacuum chamber, and the surface temperature is heated to about 100 ~ 900 degrees Celsius, while pumping the inside of the chamber with a constant vacuum with a vacuum pump, the reaction gas ( Hydrogen, nitrogen gas, etc.) is injected into the chamber to a certain pressure, and the laser light generated from the laser source is irradiated to the fixed target located in the vacuum chamber through the reflector optical device for driving, and as shown in FIGS. Similarly, the driving reflector 10 is rotated or linearly moved to irradiate the fixed target 5 and spot spots of the laser beam generated on the surface thereof are generated. Add an optical device for the enemy to be circular, elliptical, polygonal, straight, cross, etc. (no target driving motor part), and the laser beam 2 generated from the laser source 1 is condensed by the lens 3 Adjust the inclination of the reflecting surface of the driving reflector 10, which is the optical device shown in FIG. 4, to a desired angle, irradiate it to a desired point of the fixed target 5, and perpendicular to the target surface by irradiation of a laser beam. Protruding particles (plium) were deposited on the substrate 8 positioned on the substrate heater 7 to form a thin film. The present invention will be described below with reference to the drawings. Fig. 2 is a schematic view of the thin film formation process by the method, Fig. 2 is a schematic view of the thin film formation process by the laser ablation method of the present invention, Fig. 3A is a geometrical optical detail for the theoretical proof of the present invention. Conventional room 3b is a geometrical optical detail for the theoretical proof of the present invention (when the reflection surface tilt angle of the reflector is θ) and FIG. 4 is a detailed view of an example of the driven reflector of the present invention. Laser source (1), laser beam (2), condenser lens (3), vacuum chamber (4), target (5), laser plum (6), substrate heater (7), substrate (8), target ash Dedicated electric motor 9, driving reflector 10, reflecting surface 10a of driving reflector at negative (-) tilt, reflecting surface 10b of driving reflector at positive (+) tilt, protractor 10c, the reflecting mirror fixing screw 10d, the reflecting mirror 10e, the angle adjusting screw 10f, the drive shaft 10g, and the inclination angle θ (°) of the reflecting surface are shown. Referring to Figure 2 as shown in Figure 2 the substrate 8 formed in the inner center of the vacuum chamber 4, the substrate support formed on the lower substrate, and formed on the substrate to form a thin film A laser is formed on the lower plume 6, the target 5 which forms the laser plume and is irradiated by a laser beam, a support for supporting the target 5, and a lower end of the vacuum chamber 4; A laser source 1 for emitting a beam 2, a condenser lens 3 for condensing a laser beam from the laser source, and a drive reflector 10 for reflecting and irradiating the focused laser beam onto a target surface And a vacuum pump formed on one side of the reverse side, the driving reflector 10 includes a reflecting mirror 10e formed at an upper portion as shown in FIG. 4 and reflecting mirrors formed at both ends of the reflecting mirror. A screw 10d, a lower portion of the device reflecting mirror 10e, formed with an angle adjusting screw 10f for adjusting an angle, and a protractor 10c connected to the angle adjusting screw 10f for indicating an angle. And a drive shaft 10g for driving the devices. The substrate used in the present invention is a Si substrate having a crystal plane of (100) or (111), or a Ni substrate having (100) or (111), and the intensity and substrate size of the fixed target and the laser beam. According to each other placed at intervals of about 20 ~ 200 mm to face each other to enable the formation of a thin film effectively.

The above-described laser ablation apparatus and method having a drive reflector, which is a beam control irradiation optical device, when a thin film is formed on a substrate, the target surface on which the laser beam is fixed while driving the drive reflector installed outside the vacuum chamber at a low speed. The target driving motor that existed in the vacuum chamber was irradiated on the target surface so that the rule of the laser spot on the target surface was continuously changed into a circle, ellipse, polygon, straight line, cross, etc. so that the target itself could be rotated. Thin film device allows the thin film formed on the substrate to be formed in a uniform thickness over a large area, which is impossible by the conventional method by changing the position of the laser plume on the target surface every moment. Thin film forming apparatuses and methods are provided. As described in detail above, the method of forming a thin film such as a thin film device by the laser ablation of the fixed target using the driving reflector according to the present invention solves the above disadvantages of the laser ablation method having the conventional driving target. It has been confirmed that it is a thin film forming apparatus and method such as a thin film device. In addition, a thin film forming apparatus and method such as a thin film device by a laser ablation apparatus and method with a driving reflector can be effectively used for sputtering any kind of material such as metal for forming a large area thin film of uniform thickness. will be.

Claims (6)

In a thin film forming method such as a thin film device by a laser ablation method, The laser beam 2 is irradiated onto the fixed target surface by slowly driving or rotating the driving reflector 10, which can adjust the reflecting surface tilt installed outside the vacuum chamber 4, to the fixed target surface, and the laser spot on the surface of the target 5. Since the rule of the circle is an ellipse, an ellipse, a straight line, a cross shape, and the like, the target 5 itself is substantially rotated so that the target driving motor is not necessary, thereby simplifying the structure of the vacuum chamber 4. It is possible to change the ejection position of the laser plume 6 from the surface of the target 5 at any time, so that the thin film formed on the substrate 8 over a large area, and the thin film is formed with a uniform thickness. Thin film formation method, such as a thin film device by the ablation method. delete In a thin film forming apparatus such as a thin film device by a laser ablation method, A substrate 8 formed at the inner center of the vacuum chamber 4, a substrate support formed under the substrate, a laser plume 6 formed on the substrate to form a thin film, and the laser plume to form a laser beam A target 5 to be irradiated by the light source, a support for supporting the target 5, a laser generating source 1 formed at a lower end of the vacuum chamber 4 to irradiate a laser beam 2, and the laser A condenser lens 3 for condensing the beam 2, a driving reflector 10 for changing the irradiation direction of the condensed laser beam 2, and a vacuum pump formed on the opposite side thereof. Thin film forming apparatuses, such as a thin film device by the laser ablation method. The driving reflector 10 includes a reflecting mirror 10e formed at an upper portion, a reflecting mirror fixing screw 10d formed at both ends of the reflecting mirror, and the apparatus reflecting mirror 10e. It is formed in the lower portion of the angle adjusting screw (10f) for adjusting the angle, the angle adjusting screw (10f) is connected to the angle adjuster (10c) and the drive shaft (10g) for driving the device Thin film forming apparatus, such as a thin film device by the laser ablation method characterized by the above-mentioned. delete delete