KR200209326Y1 - Optical equipment for thin film deposition by laser ablation method - Google Patents

Abstract

The present invention forms a substrate (8) installed in the inner center of the vacuum chamber (4), a substrate heater (7) embedded in the lower portion of the substrate, 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 the 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 while the driving reflector 10 capable of adjusting the inclination of the reflecting surface installed outside the vacuum chamber 4 is rotated slowly or in a straight line, 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 forming apparatus.

Description

Optical equipment for thin film deposition by laser ablation method}

The present invention relates to a thin film forming apparatus 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, the 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 laser The present invention relates to an apparatus 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 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 source is irradiated to a target, small holes are formed on the surface thereof, and if 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.

After all, the present invention was devised to solve the conventional problems as described above, the object of the present invention is to form a thin film, such as a thin film device on the substrate by a laser ablation method, 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, 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 at every moment. Thin film over a large area, allowing thin films to be formed with uniform thickness To provide a thin film forming apparatus of such devices is an aspect of the subject innovation.

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

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

Figure 3a is a geometrical optical detail for the theoretical proof of the present invention

When the reflecting surface tilt angle of the reflector is 0 (same as the conventional method)

Figure 3b is a geometrical optical detail for the theoretical proof of the present invention

When the reflecting surface tilt angle of the reflector is θ

Figure 4 is a detailed view of the driving 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, while slowly driving or driving the drive reflector 10 that can adjust the reflecting surface tilt installed outside the vacuum chamber 4 in a fixed target surface 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 apparatus such as a thin film device by a laser ablation method characterized by forming a thin film with a thickness.

Referring to the present invention with reference to the drawings as follows.

1 is a schematic view of a thin film formation process by a conventional laser ablation method, FIG. 2 is a schematic view of a thin film formation process by a laser ablation method of the present invention, FIG. 3a is a geometrical optical detail for a theoretical proof of the present invention, 3 is the geometrical optical detail for the theoretical proof of the present invention (when the reflecting surface tilt angle of the reflector is θ) and FIG. 4 is the A detailed view of an example of a driving reflector is shown and includes a laser source 1, a laser beam 2, a condenser lens 3, a vacuum chamber 4, a target 5, a laser plume 6, a substrate heater ( 7), the substrate 8, the target rotational motor 9, the driving reflector 10, the reflecting surface 10a of the driving reflector at the negative inclination, the driving at the positive inclination Reflecting surface 10b, protractor 10c, reflecting mirror fixing screw 10d, reflecting mirror 10e, angle It can be seen that shows the jeolyong screw (10f), a drive shaft (10g), gradient angle θ (°) of the reflecting surface.

As shown in FIG. 2, the substrate 8 formed in the inner center of the vacuum chamber 4, the substrate support formed under the substrate, the laser plum 6 formed on the substrate to form a thin film, and the laser A laser generating source for forming a plume, formed on a target 5 irradiated by a laser beam, a support for supporting the target 5, and a lower end of the vacuum chamber 4 to emit a laser beam 2; (1), a condenser lens 3 for condensing a laser beam from the laser source, a drive reflector 10 for reflecting and condensing the condensed laser beam to a target surface, and a vacuum formed on one side thereof Consists of a pump,

The driving reflector 10 includes a reflecting mirror 10e formed at an upper portion as shown in FIG. 4, a reflecting mirror fixing screw 10d formed at both ends of the reflecting mirror, and the device reflecting mirror 10e. It is formed in the lower portion, consisting of an angle adjusting screw (10f) for adjusting the angle, a protractor (10c) connected to the angle adjusting screw (10f) indicating the angle, and a drive shaft (10g) for driving the devices It can be seen.

The substrate used in the present invention is a Si substrate having a crystal surface of (100) or (111), or a Ni substrate having (100) or (111), and having an interval of about 20 to 200 mm depending on the intensity and substrate size of the fixed target and the laser beam. Placed to face each other so as to enable the formation of a thin film effectively.

In the method of using the device of the present invention, the surface of the object (Si or Ni) to form a thin film with alcohol or acetone is washed with an ultrasonic cleaner for about 30 minutes, and then held in the object holder in the vacuum chamber, and then the surface temperature is reduced. While heating to about 100 to 900 degrees Celsius, the inside of the chamber is pumped to a constant vacuum with a vacuum pump, and then a 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 After irradiating the fixed target located in the vacuum chamber through the driving reflector optical device, as shown in FIGS. 2 and 3, the driving reflector 10 is rotated or linearly moved to irradiate the fixed target 5. Add an optical device that allows the spot path of the laser beam generated on the surface to be circular, ellipse, polygon, straight line, cross shape, etc. ), The laser beam 2 generated from the laser source 1 is condensed with the lens 3, and the inclination of the reflective surface of the driving reflector 10, which is the optical device shown in FIG. 4, is adjusted to a desired angle. Irradiate to a desired point of the fixed target (5), by depositing particles (flute) protruding in the direction perpendicular to the target surface by the laser beam is deposited on the substrate (8) located on the substrate heater (7) To form.

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 that allows the thin film formed on the substrate to be formed in a uniform thickness over a large area, which is impossible with the conventional method by changing the position of the laser plume on the target surface from time to time. Thin film forming apparatuses and methods are provided.

As described above in detail, a thin film forming method such as a thin film device by laser ablation of a fixed target using a drive reflector of the present invention solves the above disadvantages of the laser ablation method having a conventional drive 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 (1)

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 one side of the condenser lens 10; Thin film forming apparatus, such as a thin film device by the laser ablation method.