KR100689157B1 - Manufacturing method of al-si alloy films - Google Patents

Abstract

A method for forming an Al-Si alloy film having high reflectivity and superior corrosion resistance at high temperature by controlling silicon content of an Al-Si alloy in a crucible and controlling electric power of an electron beam, thereby evaporating the Al-Si alloy at a proper evaporation rate is provided. A manufacturing method of an Al-Si alloy film comprises: a vacuum process(S11) of vacuuming a vacuum chamber within a vacuum deposition equipment to a range of 10^-2 to 10^-5 torr; a substrate cleaning process(S11) of injecting argon gas into the vacuum chamber and applying a negative voltage of 400 to 1000 V to a substrate mounted on a substrate holder installed within the vacuum chamber, thereby glow discharging the substrate to clean the substrate; a substrate heating process(S13) of heating the substrate to a temperature range of 200 to 350 deg.C to form a film on the substrate cleaned by the substrate cleaning process; and an evaporation depositing process(S14) of evaporating an evaporation material within an alumina crucible by controlling an electron beam power to 2.5 to 4.0 kW to obtain a preset evaporation rate when the substrate is heated, and depositing the evaporate Al-Si alloy evaporated for a determined time by opening a shutter when the electron beam power has a preset power value.

Description

Manufacturing method of aluminum silicon alloy film {Manufacturing method of Al-Si Alloy films}

1 is a view showing the configuration of the film production apparatus of the present invention,

2 is a flow chart showing the process of the present invention,

3 is a graph showing a silicon content change according to the electron beam power in the present invention,

Figure 4 is a graph showing the relative reflectance change according to the silicon content in the present invention.

Description of the main symbols in the drawings

1: vacuum chamber 2: electron beam evaporation source

3: alumina crucible 4: substrate

5: Substrate holder 6: Substrate heating device

7: Shutter 8: Thickness gauge

9: gas inlet 10: vacuum gauge

The present invention relates to an aluminum-silicon alloy film of a metal material, and more particularly, an aluminum-silicon alloy film formed by depositing an aluminum-silicon alloy film on a surface of a metal material on a substrate has high reflectivity and excellent corrosion resistance at high temperatures. A method for producing an aluminum-silicon alloy film to have.

In general, aluminum is beautiful in color and has excellent corrosion resistance and heat resistance, so it is widely used in decorative coatings such as cosmetic cases and accessories, as well as conductive films of semiconductors, protective films of magnetic materials and steel sheets, home appliances in thermal systems, and automotive mufflers. It is used. In addition, aluminum has a wide variety of industrial applications due to its properties (low density, excellent workability, reflectivity and thermal conductivity). Recently, as the space development and the aviation industry are greatly developed, researches to improve the corrosion resistance and mechanical properties by coating aluminum on various materials have been actively conducted. McDonnell Douglas, for example, uses aluminum as a coating for various parts used in airplanes as a corrosion and wear resistant material. On the other hand, in Germany, aluminum is vacuum-deposited on steel sheets and used in containers or home appliances.

Aluminum is most commonly used for physical vapor deposition because its efficiency is low when it is coated with electroplating. Physical vapor deposition includes vacuum deposition, sputtering and ion plating, and ion plating is generally used for the purpose of improving corrosion resistance.

Aluminum has a low melting point, high vaporization temperature, and high thermal conductivity. When evaporated using a conventional water-cooled copper crucible, a high power of 5 kW or more is required to obtain evaporation necessary for proper deposition. Therefore, a method of shielding heat transfer by inserting graphite or alumina crucibles into a water-cooled copper crucible has been widely used.

Aluminum coatings are especially applied to reflecting plates, and are widely used for heat reflecting plates using infrared rays, optical mirrors, and the like. In order to use an aluminum film in a high temperature and high corrosion resistance environment, it is necessary to improve the thickness of the film, and as the thickness of the film is increased, roughness is generally worsened and the reflectance is significantly worsened. In order to solve this problem, a multilayer coating or a high corrosion resistant coating layer such as anodizing is often formed. However, these methods have a disadvantage in that a process may be difficult and adhesion failure may occur when forming a multilayer. Accordingly, when silicon is added to aluminum, the method of adding silicon to the aluminum film layer is used by using the point that the particles become fine and the reflectance is improved. The easiest way to add silicon to the aluminum film is to use an aluminum-silicon mother alloy in which silicon is added to aluminum as the evaporation material.

However, when the aluminum-silicon master alloy is evaporated by using an electron beam evaporation source as described above, two elements are separated from each other while the alloy is melted, and an alloy completely different from the master alloy component is deposited on the substrate due to the difference in vapor pressure of the material. Will be. For example, when a silicon-containing 30% silicon-silicon is deposited on a substrate using a mother alloy, the content of silicon present in the coating is less than 1%. If the silicon content is too low, there is a problem that the reflectance does not improve so much.

Therefore, in the prior art, an aluminum film forming method is required to properly control the silicon content in forming the aluminum film containing silicon.

The present invention is to solve the above-mentioned problems of the prior art, the aluminum-silicon alloy in which silicon is added to aluminum in one crucible to control the silicon content of the aluminum-silicon alloy, and also by adjusting the power of the electron beam to evaporate appropriate It is possible to form an aluminum-silicon alloy film having high reflectance and excellent corrosion resistance at high temperature by evaporating to have a rate, and also providing a method of manufacturing an aluminum silicon alloy film having a very high reflectance even at a thickness of 5 μm or more. It is for that purpose.

In the method for producing an aluminum-silicon alloy film of the present invention for achieving the above object, in the method of evaporating the aluminum-silicon alloy containing silicon to form a film by vacuum deposition,

Vacuuming the vacuum chamber in the vacuum deposition apparatus;

A substrate cleaning process in which argon gas is injected when the proper vacuum pressure is formed by the vacuum process, and the specimen is cleaned by applying a negative voltage to the substrate mounted on the substrate holder in the vacuum chamber;

A substrate heating process of heating the substrate cleaned by the substrate cleaning process to have an appropriate temperature for forming a film;

When the substrate is heated to an appropriate temperature, the substrate is heated at a proper temperature to control the electron beam power to have a predetermined evaporation rate to evaporate the evaporation material in the alumina crucible, and when the electron beam power has a predetermined power value, It characterized in that it comprises a; evaporation deposition process for depositing the aluminum-silicon alloy evaporated for a predetermined time to the substrate.

The evaporation material is characterized in that the aluminum silicon alloy having a Si content of 17% by weight or more.

The substrate heating process is characterized in that the heating temperature of the substrate is heated in the range of 200 ~ 350 ℃.

The evaporation deposition process is performed by controlling the electron beam power value such that the evaporation rate of the aluminum silicon alloy is in the range of 0.5 μm to 1.5 μm / minute.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the structure of the film manufacturing apparatus of this invention.

As shown in FIG. 1, the vacuum evaporation apparatus of the present invention includes a vacuum chamber 1, an electron beam evaporation source 2 for evaporating an aluminum-silicon alloy in the vacuum chamber 1, and an alumina crucible containing evaporation material to evaporate ( 3), the substrate holder 5 for mounting the substrate 4, the substrate heating device 6 for heating the substrate 4, the thickness gauge 8 for measuring the thickness of the film, and the vacuum for measuring the degree of vacuum. It comprises a gauge 10.

2 is a flow chart showing a process for forming an aluminum-silicon alloy film according to the present invention by vacuum deposition on a substrate in a vacuum deposition apparatus having the above-described configuration.

As shown in FIG. 2, in order to form the aluminum-silicon alloy film according to the present invention by vacuum deposition, first, the substrate 4 is mounted on the substrate holder 5, and the grain-shaped aluminum-silicon alloy is alumina crucible (3). ), And then evacuated using a vacuum pump (not shown) so that the vacuum degree is 10 ^-5 Torr or less (vacuum process) (S11).

When the vacuum degree is 10 ⁻⁵ Torr or less, argon gas is injected through the gas inlet 9 to clean the substrate 4, and a negative voltage is applied to the substrate 4 to clean the specimen. Cleaning of the substrate 4 includes removing not only impurities such as organic matter present in the substrate 4, but also naturally occurring oxide films. If these impurities are not removed sufficiently, it will affect the adhesion and should be sufficiently cleaned. The cleaning of the substrate 4 is performed by inducing a glow discharge by applying a negative voltage of 400 to 1000 V to the specimen in an argon gas atmosphere of about 10 ^-2 Torr. In this way, argon ions present in the discharge region collide with the specimen to remove impurities present in the specimen (substrate cleaning process) (S12).

When the cleaning of the substrate 4 is completed by the S12 process, the substrate is heated by adjusting the temperature of the substrate 4 to a desired condition by using the substrate heating apparatus 6 to heat the substrate 4 so that the substrate is appropriately prepared. Temperature control is performed to have a temperature. At this time, the substrate is preferably controlled to have a range of 200 ~ 350 ℃ as described below. This is because the reflectance is low when the temperature of the substrate 2 is 200 ° C. or lower, and when the temperature of the substrate 2 is higher than 350 ° C., the illuminance decreases as the crystallinity of the film increases, thereby lowering the reflectance (substrate heating process) (S13).

When the temperature control of the substrate 4 is completed by the process S13, the filament of the electron beam evaporation source 2 is heated to evaporate the evaporation material in the alumina crucible 3. When the power of the electron beam reaches an appropriate power, the shutter 7 is opened to deposit an aluminum-silicon alloy for a predetermined time. The evaporation rate of the aluminum-silicon alloy is suitably 0.5-1.5 μm per minute. When the evaporation rate is 0.5 μm or less, the silicon content in the film is low so that the reflectance does not improve so much. ), Etc., to damage the coating. Herein, the proper power of the electron beam power is closely related to the evaporation rate of the deposition material. When the electron beam power reaches 3.5 kW, the evaporation rate is 1 μm per minute. Here, the evaporation rate is controlled by the power of the electron beam, but the power of the above-described electron beam may vary depending on the surrounding environment and does not have a constant value according to the evaporation rate. Therefore, as described above, the power intensity of the electron beam should be adjusted according to the situation so that the evaporation rate of the aluminum-silicon alloy is 0.5-1.5 μm / min (evaporation and deposition process) (S14).

When the above steps S11 to S14 are performed, all processes are completed.

The above-described method for manufacturing an aluminum silicon film according to the present invention can be very usefully applied to various aspects such as an infrared reflecting heat treatment apparatus requiring high reflectance in a high temperature and high corrosion resistance environment.

Hereinafter, the Example of this invention is described.

<Example 1>

3 is a graph showing a silicon content change according to the electron beam power as Example 1 of the present invention.

3 shows a case of manufacturing an aluminum-silicon alloy on a mirror polished stainless steel sheet. A stainless steel substrate 4 having a width of 20 cm, a height of 15 cm, and a thickness of 0.8 mm was installed in the substrate holder 5, and an aluminum-silicon alloy containing 30% by weight of silicon was charged into the alumina crucible 3, followed by vacuum evacuation. Was carried out.

After the vacuum degree was 10 ⁻⁵ Torr or less, argon gas was injected through the gas inlet 9 to clean the substrate 4, and a negative voltage was applied to the substrate 4 to clean the specimen. In Example 1 described above, a negative voltage of 700 V was applied to the specimen in an argon gas atmosphere of 6 × 10 ⁻² Torr to induce a glow discharge, followed by cleaning for 30 minutes.

After the cleaning of the board | substrate 4 was completed, the board | substrate heating apparatus 6 was started and the board | substrate was heated to 250 degreeC. When the temperature of the substrate 4 rises and maintains 250 degreeC, the next step will be the heating step of the alumina crucible 3. When the power of the electron beam was gradually increased from the low power to 3.5 kW, the shutter 7 was opened and deposited for 10 minutes to prepare a 10-micrometer thick aluminum-silicon alloy containing 30 wt% silicon.

3 is a diagram showing the silicon content in the film according to the power of the electron beam evaporation source 2 as an embodiment using alumina. When the power of the electron beam is 2.5 kW or more, the content of silicon increases rapidly, and when 3.5 kW is reached, 30 wt% of silicon is contained in the film.

<Example 2>

Figure 4 is a graph showing the relative reflectance change according to the silicon content in the present invention.

4 is a graph showing the relative reflectance of the aluminum film according to the Si content in the film to explain the effect of the present invention. The graph compares the reflectance values of specimens in which an aluminum film is deposited on a mirror polished stainless substrate by 0.2 mm as a reference value (100%) and an aluminum-silicon alloy is deposited on the same substrate by a thickness of 10 mm. As can be seen in Figure 3 it can be seen that the reflectance is improved to 50% or more when the Si content is 17% by weight or more.

The present invention as described above enables the formation of a film having excellent corrosion resistance and excellent film properties of high reflectance at high temperature, and provides the effect of improving productivity by simplifying the aluminum-silicon film manufacturing process.

Claims (4)

In the method of evaporating an aluminum-silicon alloy containing at least 17% by weight of silicon to form a film by vacuum deposition, Vacuuming the vacuum chamber in the vacuum deposition apparatus to 10 ^-2 to 10 ^-5 Torr; A substrate cleaning process of cleaning the specimen by injecting an argon gas and applying a negative voltage of 400 to 1000 V to the substrate to be mounted on the substrate holder in the vacuum chamber to glow discharge the vacuum process; A substrate heating process of heating to 200 to 350 ° C. to form a film on the substrate cleaned by the substrate cleaning process; When the substrate is heated by the substrate heating process, the electron beam power is controlled to 2.5 to 4.0 kW to have a predetermined evaporation rate to evaporate the evaporation material in the alumina crucible, and the shutter when the electron beam power has a predetermined power value. The evaporation deposition process for depositing the aluminum-silicon alloy evaporated for a predetermined time by opening the substrate; aluminum silicon film manufacturing method comprising a. delete delete The method of claim 1, The evaporation deposition process is performed by controlling the electron beam power value so that the evaporation rate of the aluminum silicon alloy is in the range of 0.5 ㎛ / 1.5 ~ 1.5 ㎛ / minute.

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