JPH04107267A - Vacuum-deposition vaporization source using laser - Google Patents

Abstract

PURPOSE:To stably maintain the vaporization rate of various materials to be irradiated by transiently heating the material in the vacuum-deposition vaporization source using a laser to a high temp., then cooling the material and supplying the cooled material. CONSTITUTION:The powder of Al2O3, etc., to be irradiated supplied from a powder inlet 19 is agitated by rotating a piston 20, and supplied toward a cooling body 14 by raising the piston 20. The powder is passed through the cooling body 14, sent to a heating and melting body 13, heated and melted. The molten layer is further pushed up by the powder coming from the lower part to a cooling and resolidifying body 12, cooled and resolidified. The material 6 to be irradiated, which has been resolidified, vitrified and converted to a single crystal, is irradiated with a laser beam 1, heated and vaporized without being cracked, and the vaporized particles are deposited on an opposed substrate 9 to form a coating film. The state of the material 6 is adjusted by the length and diameter of the cooling and resolidifying body and the cooling rate of a cooling mechanism.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] This invention relates to an evaporation source for a material to be irradiated in a laser evaporation apparatus for depositing a film on a substrate.

[Prior Art] FIG. 6 is a schematic diagram showing a conventional laser vapor deposition apparatus disclosed in, for example, Japanese Patent Publication No. 62-230.

In the figure, (1) is a laser beam, (2) is a laser beam (1
), the first plane mirror (3) changes the direction of the laser beam (1
), and (4) is a transmission window (5) that takes in the laser beam (1) focused by lens (3).
(6) is a cylindrical irradiated material which is located in the vacuum chamber (4) and rotates in the direction of the arrow;
(7) is a second plane mirror provided in the vacuum chamber (4), which changes the direction of the laser beam (1) that enters the vacuum chamber (4) through the transmission window (5) and Irradiation material (6
) to illuminate the surface. (8) is the irradiated material (6
) A heater that heats the entire body, (9) a substrate provided to face the irradiated material (6), and (10) a shutter.

Next, the operation will be explained.

The laser beam (1) is horizontally changed in optical path by the first plane mirror (2), focused by the lens (3), and then passed through the transmission window (5).
The optical path is changed again by the second plane mirror (7), and then the heater (8)
The surface of the irradiated material (6) heated to a predetermined temperature is irradiated. At this time, the condensing lens (3) focuses on the irradiated material (6).
The focal length and position are adjusted so that the beam is focused near the upper irradiation point. In addition, at the initial stage when the conditions are unstable, the surface of the substrate (9) is covered with a shutter (10).
), and after the conditions have stabilized, the shutter (10) is removed and the substrate (9) surface directly faces the irradiated material (6). Irradiated material (
The surface layer 6) evaporates due to rapid temperature rise, and evaporated particles fly out toward the substrate (9) and are deposited on the substrate (9). The material to be irradiated (6) is rotated in the direction of the arrow, and the surface layer of the material to be irradiated (6) is heated in sequence by changing the irradiation position, repeating evaporation, and the evaporated particles form a deposited film on the substrate (9). Form. In the above process, the surface layer of the material to be irradiated (6) receives a sudden thermal shock due to the focused irradiation of the laser beam (1), so even if the surface is preheated in the heater (8), the surface layer cracks. Depending on the material, cracks may propagate or occur inside the irradiated material (6). In addition, in order for the irradiated material (6) to withstand this sudden thermal shock, it may be necessary to add additives and sinter the ceramic material;
) may not be available.

[Problem to be solved by the invention] Conventional laser evaporation equipment is configured as described above, so cracks occur on the surface of the irradiated material, reducing the area that can absorb laser light and reducing the evaporation rate. However, there was a problem in that the evaporation rate of the irradiated material could not be maintained stably because the surface of the irradiated material cracked and fell, changing the position irradiated with the laser beam and changing the evaporation rate. Further, in some cases, the material to be irradiated may be severely cracked or destroyed, resulting in a problem that the vapor deposition cannot be maintained. Furthermore, in the case of ceramic materials that need to be sintered with additives added to form them into a cylindrical shape as the irradiated material, there is a problem that it may not be possible to form a film with the desired composition because the additives are mixed into the evaporated material. There was a point. Furthermore, there was also the problem that some materials could not be vapor deposited because they could not be manufactured into the shape of the irradiated material.

This invention was made in order to solve the above-mentioned problems, and the purpose is to obtain an evaporation source for vacuum evaporation using a laser that can efficiently supply a shape to the irradiated material in a state where it is easy to stably evaporate it. Do - [to 1! ! Means for Solving Problem 1] The evaporation source for vacuum evaporation using a laser according to the present invention is provided with a mechanism for once raising the temperature of the irradiated material to a high temperature and then recooling and supplying the material.

[Function] The evaporation source for vacuum evaporation using a laser in this invention is as follows:
By raising the irradiation material to a high temperature and then recooling it before supplying it, it is possible to prevent cracks and cracks from occurring due to sudden thermal shock, which can cause the evaporation rate to fluctuate and make it impossible to continue vapor deposition.

[Example code] Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

Fig. 1 is a schematic diagram of the entire evaporation apparatus using an evaporation source for vacuum evaporation using a laser according to the present invention, Fig. It is a sectional view taken along the line ■-■ in FIG. 2.

In Figures 1, 2, and jIa, (1) is a laser beam, (4) is an evacuated vacuum chamber, and (6 is
) is the irradiated part of the irradiated material that is irradiated with the laser beam, (
11) is a holder for an evaporation source provided for supplying the material to be irradiated.

The evaporation source holder (11) includes a cooling resolidified body (12) for melting and resolidifying and supplying the irradiated material (6);
a heating melt (13) for melting the irradiated material;
A cooling body (14) separates a powder supply section (15) that supplies the material to be irradiated to the heated melt and the heated melt (13).
).

The cooled resolidified body (I2) is provided with a cooling mechanism, and here a method of arranging cooling pipes (16) as shown in FIG. 2.3 was used.

The heating molten body (I3) is provided with a heating mechanism, and here a method of arranging a coil (17) and performing high frequency heating was used.

The cooling body (14) is also provided with a cooling mechanism, and here a method using a cooling pipe (18) was used.

The powder supply section (15) includes a powder supply port (19),
Stir the supplied powder. It also consists of a piston (20) that rotates up and down and pushes up toward the cooling body (14).

In addition, these cooling mechanisms and heating mechanisms are used to control the irradiated material (6) ranging from powder to re-solidified material and the shielding plate (21).
It is divided into Here, a pipe made of a material that is the same as the material to be irradiated or has a high melting point is used as the shielding plate. Further, the heating mechanism for the heated molten body (13) and the cooling mechanism for the cooled resolidified body (12) and the cooling body (14) are separated by a heat insulating material (22).

Next, the operation will be explained.

In this case, Al2O3 will be used as an example of the material to be irradiated.

The Al2O3 powder supplied from the powder supply port (19) is stirred by rotating the piston (20), and by pushing the piston (20) up.
It is supplied in the direction of the cooling body (14). These powders are heated and melted when they reach the heated melting body (13) via the cooling body (14). This molten layer is further pushed upward by the powder continuing from below, and the cooled re-solidified material (
12), it is cooled and solidified again. The irradiated material (6), which has been re-solidified and vitrified or single crystallized, is heated and evaporated without causing any cracks even when irradiated with the laser beam (1), and the evaporated particles are evaporated onto the substrate ( 9) A film can be formed by depositing on the surface.

The state of the irradiated material (6) can be adjusted by the length and diameter of the cooled resolidified body and the cooling rate of the cooling mechanism.

For this reason, the material to be irradiated (6) can be supplied in a molten state heated to -degrees high temperature or in a semi-solidified state.

In addition, the irradiated material (6) is formed after once melting the powder supplied by the heated melt (13).
A method may be used in which the amount of energy input to the coil (17) is adjusted to grow the crystal grains at a temperature that does not melt.

In addition, the powder to be supplied can be of various particle sizes, so ultrafine particles may be used. In this case, even if the amount of energy input to the coil is reduced, sintering or crystal grain growth can be achieved at low temperatures. I can do it.

Further, as the laser light, high-energy laser light such as a CO2 laser, a YAG laser, or an excimer laser light such as A r F or K r F may be used.

Further, a high energy beam such as an electron beam or an ion beam may be used instead of the laser beam.

Also, the beam may be continuous wave or pulsed.

Further, although a piston is used to push up the powder, other methods such as compressed gas flow may also be used.

Furthermore, the holder (11) of the evaporation source may be made rotatable in order to rotate the material to be irradiated (6).

Further, although the shape shown in FIG. 3 is cylindrical, other shapes such as rectangular shapes may be used. Furthermore, as shown in FIGS. 4 and 5, a configuration may be adopted in which the irradiation position of the laser beam (1) irradiated onto the irradiated material (6) can be changed.

Moreover, methods other than high frequency heating may be used for heating.

Examples include a method of arranging a heater, a method of using an infrared reflecting furnace, etc.

Further, as a cooling method, a method of flowing a coolant such as liquid nitrogen cooling, a method of disposing a ceramic material with good thermal conductivity, etc. may be used.

[Effects of the Invention] As described above, according to the present invention, since the evaporation source for vacuum evaporation using a laser is configured to heat the irradiated material once to a high temperature and then re-cool it before supplying it, it is possible to avoid sudden thermal shock. Vacuum evaporation using a laser that can continuously maintain a stable evaporation rate and deposit various irradiated materials without causing cracks or fractures that would cause the evaporation rate to fluctuate or make it impossible to continue evaporation. This has the effect of providing a laser evaporation apparatus equipped with an evaporation source.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of an entire vapor deposition apparatus using an evaporation source for vacuum evaporation using a laser according to the present invention, and FIG. 2 is a schematic diagram showing an evaporation source for vacuum evaporation using a laser according to an embodiment of the present invention. 3 is a cross-sectional view taken along the line ■-■ in FIG. 2; FIG. 4 is a plan view of a schematic configuration diagram showing an evaporation source for vacuum evaporation using a laser according to another embodiment of the present invention; FIG. 5 is a plan view of a schematic configuration diagram showing an evaporation source for vacuum evaporation using a laser according to still another embodiment of the present invention, and FIG. 6 is a schematic configuration diagram showing a conventional laser evaporation apparatus. In the figure, (1) is a laser beam, (3) is a condensing lens, (
4) is a vacuum chamber, (5) is a transmission window, (6) is a material to be irradiated, (9) is a substrate, and (11) is an evaporation source. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] In a vacuum chamber, the irradiated material is irradiated with a focused laser beam, the irradiated material is evaporated, and the evaporated particles are deposited on a substrate placed in the evaporation direction to form a film. An evaporation source for vacuum evaporation using a laser, which is characterized in that it is supplied after being recooled.