A suspended evaporation source and coating material for preparing high-purity metal thin films
Through the combination of suspended smelting evaporation coil and high-frequency power supply, combined with gas ionization electrode and evaporation deposition rate sensor, the problems of metal material pollution and evaporation rate control in vacuum evaporation coating are solved, and high-purity and efficient preparation of metal thin films are achieved, which improves the Film formation quality and application value.
Patent Information
- Application Number
- CN202211675596.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-12-26
- Publication Date
- 2024-12-24
- Estimated Expiration
- 2042-12-26
AI Technical Summary
In the vacuum evaporation coating process, high-purity metal materials are easily contaminated during heating, resulting in a decrease in the purity of the film and a difficult evaporation rate to control, affecting the optical and electrical properties of the film.
The suspension smelting evaporation coil and high-frequency power supply are combined to suspend the metal material in the air through the action of induction current and magnetic field to heat it to avoid contact with the crucible, and combine it with the gas ionization electrode and the evaporation deposition rate sensor to achieve stable suspension and efficient evaporation.
Maintaining high purity metal materials ensures high optical properties and stable evaporation rate of the film, extends the life of the crucible and improves the film formation quality.
Smart Images
Figure CN115928023B_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a suspension evaporation source and a coating material for preparing a high-purity metal film, belonging to the coating field. Background Art
[0002] High-metal films are widely used in the optical and semiconductor industries, usually for the preparation of reflectors or electrodes. The optical / electrical properties of the film are closely related to the purity of the metal. Often, impurities of tens of ppm will cause a significant drop in reflectivity or a significant increase in resistance. Especially in the field of chip manufacturing, in order to ensure the stability of the process and the high performance of the film, the purity of the evaporated material is usually very high. The purity of metal and single-element coating materials often reaches 5N-9N.
[0003] In the vacuum evaporation process, the metal is heated to melt before the evaporation coating process begins. In this process, metal molecules begin to escape from the material after being exposed to high temperatures, forming metal vapor and diffusing to the workpiece, forming a thin film on the surface of the workpiece. The current mainstream process is to use resistance heating or electron beam heating to heat and evaporate high-purity metal materials. On a few high-end equipment, ion beam or laser heating is also used for evaporation.
[0004] However, no matter which method is used for evaporation, the material must be heated to 1,500 to 3,000 degrees and maintained for a period of time. In this process, the temperature of the crucible will rise due to the high thermal conductivity of the metal. Crucibles used for evaporation coating are usually made of high-temperature resistant materials such as tungsten, molybdenum, BN, C, or water-cooled copper. Crucibles made of metal materials can easily form a eutectic state with high-temperature liquid metals and cause pollution; non-metallic crucibles are less polluting, but elements such as B, N, and C can also easily enter the metal melt to form impurities and reduce the purity of the material. When the purity of the coating material decreases, the film will not meet the designed performance indicators. Therefore, in vacuum evaporation coating, high-purity metal coatings require one-time rapid evaporation to complete the coating process before the material is contaminated. This not only shortens the life of the crucible, but also wastes most of the material, and the quality of the film is difficult to guarantee. Moreover, since the coating thickness that can be prepared by a single crucible is very thin, when continuous production or preparation of thicker metal films is required, the vacuum evaporation process is often difficult to meet the requirements under existing technical conditions.
[0005] Vacuum levitation melting technology has been applied in the high-purity metal purification and smelting industry. During the vacuum melting process, high-purity metal materials generate induced current and magnetic field under the action of the oscillating magnetic field generated by the coil. The interaction between the coil magnetic field and the induced magnetic field allows the material to suspend in the center of the coil, and at the same time, it is affected by the resistance heat generated by the induced current, generating heat inside and melting. Since the metal melt does not contact the crucible, the purity of the material is guaranteed.
[0006] However, this technology has not been applied to the field of vacuum evaporation coating due to some limitations. When a vacuum suspension melting coil is used to heat the metal, as the metal melts, its electrical properties such as resistance are constantly changing as the temperature rises. At the same time, since the melt itself is in liquid state, under the multiple effects of electromagnetic force and gravity, the melt will present a chaotic convection state. At this time, since the electrical properties and material flow of the material itself are uncertain, the position of the material is often in a state of constant jumping, and the temperature will also fluctuate with the position. In this state, it is impossible to accurately control and ensure a stable evaporation rate. Therefore, it cannot be used as a vacuum evaporation source.
[0007] Therefore, it is necessary to invent a suspended evaporation source for preparing high-purity metal films to solve the above problems. Summary of the invention
[0008] The purpose of the present invention is to provide a suspended evaporation source and a coating material for preparing a high-purity metal film, which evaporates and coats the high-purity metal material in a suspended heating manner, thereby avoiding the problem of high-purity metal material being contaminated during the evaporation process and achieving good film quality.
[0009] In order to achieve the above object, the present invention provides the following technical solutions:
[0010] A suspension evaporation source for preparing a high-purity metal film is arranged in a vacuum chamber of a coating machine, comprising:
[0011] The suspension smelting evaporation coil comprises a suspension coil spirally wound in the same direction away from each other along the axis direction, and a stabilizing coil arranged above the suspension coil and having a current direction opposite to that of the suspension coil;
[0012] A high-frequency power supply is connected to the suspension smelting evaporation coil to form a closed loop, and the high-frequency power supply provides an alternating voltage;
[0013] The liner is a hollow sleeve arranged in the suspension smelting evaporation coil, the suspension smelting evaporation coil is wound on the outer wall of the liner, 3 to 6 ventilation holes are opened on the bottom of the liner, and the 3 to 6 ventilation holes are connected to high temperature resistant air inlet pipes;
[0014] The suspension coil has 4 to 7 layers and the spacing between every two layers is equal. The diameters of the bottom 2 to 3 layers of the suspension coil are the same, and the diameters of the upper 2 to 4 layers gradually increase. The stabilizing coil is integrally formed with the suspension coil but is wound in opposite directions. The diameter of the stabilizing coil is consistent with the diameter of the uppermost layer of the suspension coil. The spacing between the stabilizing coil and the uppermost layer of the suspension coil is greater than the spacing between every two layers of the suspension coil. The stabilizing coil cooperates with the suspension coil to allow the metal material to stably suspend between the stabilizing coil and the suspension coil.
[0015] Furthermore, the suspension evaporation source also includes an evaporation deposition rate sensor disposed above the suspension smelting evaporation coil.
[0016] Furthermore, the frequency range of the high-frequency power supply is 300-800 kHz, and the power range is 50-100 kW.
[0017] Furthermore, the suspension coil has 7 layers, the lower 3 layers of the suspension coil have the same diameter and an inner diameter of 15 mm, the upper 4 layers of the suspension coil each have a diameter 5 mm larger than the lower layer, the distance between each layer of the suspension coil is 4 mm, and the distance between the stabilizing coil and the suspension coil is 7 mm.
[0018] Furthermore, the suspension evaporation source further includes a gas ionization electrode disposed outside the air inlet pipe, and a high-voltage bias power supply connected to the gas ionization electrode.
[0019] Furthermore, the inner lining is a fused quartz hollow sleeve.
[0020] Furthermore, a water-cooled crucible for recovering the coating material is provided at the bottom of the inner lining.
[0021] Furthermore, there are six ventilation holes, and the six ventilation holes are evenly distributed along the bottom edge of the lining.
[0022] Furthermore, the suspended evaporation source also includes an automatic feeding arm disposed above the lining, and the automatic feeding arm includes a material guide rail and an automatic unloading member connected to the material guide rail.
[0023] A coating material for preparing a high-purity metal film, wherein the coating material is any one or more of a plurality of high-purity metals, wherein the plurality of high-purity metals include Ag with a purity > 4N, Cu with a purity > 4N, Au with a purity > 4N, and Al with a purity > 5N, and the coating material is spherical particles of uniform size.
[0024] The beneficial effects of the present invention are:
[0025] The present invention provides a suspension melting evaporation coil and a high-frequency power supply coordinated therewith, so that an induced current that can heat the metal material and a new magnetic field are generated inside the metal material. The new magnetic field cooperates with the magnetic field of the suspension coil and the magnetic field of the stabilizing coil to suspend the metal material in the air, and then heats and evaporates the high-purity metal material through vacuum suspension heating. The coating material used is a high-purity metal ball with a consistent particle size, the weight of each feed is consistent, the amount of each feed is fixed, and the coating rate is stable. The high-purity metal material is stably suspended between the suspension coil and the stabilizing coil during the melting process, avoiding various contaminations caused by material contact, maintaining the high purity of the material itself, and thus the formed film has higher optical properties. An inner liner is placed inside the suspension melting evaporation coil to prevent the metal material from sputtering or evaporating and condensing onto the coil during heating and evaporation, causing the coil to ignite. The suspension evaporation source has a simple structure, high film quality, and strong application value.
[0026] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for describing the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.
[0028] Figure 1 A schematic diagram of the structure of a suspension evaporation source for preparing a high-purity metal film according to a preferred embodiment of the present invention;
[0029] Figure 2 A schematic structural diagram of a suspension evaporation source for preparing a high-purity metal film from another angle shown in a preferred embodiment of the present invention;
[0030] Figure 3 This is a schematic structural diagram from another angle of a suspended evaporation source for preparing a high-purity metal film, shown in a preferred embodiment of the present invention.
[0031] in:
[0032] 1. Suspension smelting evaporation coil; 11. Suspension coil; 12. Stabilization coil; 2. Lining; 21. Vent hole; 3. Water-cooled crucible; 4. Automatic feeding arm; 41. Material guide rail; 42. Automatic unloading parts; 5. Hopper. DETAILED DESCRIPTION
[0033] The present invention discloses a suspended evaporation source and a coating material for preparing a high-purity metal film, which are suitable for suspending a metal material in the air, and then heating and evaporating the high-purity metal material by vacuum suspension heating, thereby avoiding the problem of high-purity metal material being contaminated during the evaporation process and ensuring that the evaporation process is stable and continuous.
[0034] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.
[0035] See also Figures 1 to 3 A suspension evaporation source for preparing high-purity metal film is arranged in a vacuum chamber (not shown) of a coating machine, and includes: a suspension melting evaporation coil 1, a high-frequency power supply (not shown), a liner 2, an evaporation deposition rate sensor (not shown), a water-cooled crucible 3, an automatic feeding arm 4, and a hopper 5.
[0036] The suspension smelting evaporation coil 1 comprises a suspension coil 11 which is spirally wound in the same direction away from each other along the axis direction, and a stabilizing coil 12 which is arranged above the suspension coil 11 and has a current direction opposite to that of the suspension coil 11. The suspension coil 11 has 4 to 7 layers and the spacing between each two layers is equal. When the current passes through the suspension coil 11, a constantly oscillating magnetic field is first formed. Since the suspension coil 11 has many windings, the magnetic field generated by the suspension coil 11 will cause a circular induced current to be generated inside the metal material ball at the center of the coil. This current will generate a new magnetic field, which repels each other with the magnetic field of the suspension coil 11. This repulsive force offsets the gravity of the metal material and can thus hold the metal. At the same time, the stabilizing coil 12 at the top provides a magnetic field opposite to that of the suspension coil 11. In this way, when the ball is at a low position, the stabilizing coil 12 can provide attraction to make the ball rise, and when the ball is at a too high position, it can stimulate the current inside the ball to provide repulsion to make the ball fall, thereby ensuring that the position of the metal ball is more stable. When the ball melts, the suspension force on the ball decreases due to the increase in resistance. The use of the stabilizing coil 12 can ensure that the ball can be maintained at the same height at different temperatures, thereby ensuring the stability of the evaporation process.
[0037] The diameters of the bottom 2 to 3 layers of the suspension coil 11 are the same, and the diameters of the top 2 to 4 layers gradually increase. The stabilizing coil 12 is integrally formed with the suspension coil 11 but is wound in the opposite direction. The diameter of the stabilizing coil 12 is consistent with the diameter of the top layer of the suspension coil 11, and the distance between the stabilizing coil 12 and the top layer of the suspension coil 11 is greater than the distance between every two layers of the suspension coil 11. This makes the magnetic field strength at the bottom of the suspension coil 11 greater than that at the top. When the metal material is at a lower position, the repulsion it receives is greater, and when it is at a higher position, the repulsion it receives is smaller. The stabilizing coil 12 cooperates with the suspension coil 11 to allow the metal material to stably suspend between the stabilizing coil 12 and the suspension coil 11.
[0038] In this embodiment, the suspension coil 11 has 7 layers, the lower 3 layers of the suspension coil 11 have the same diameter and an inner diameter of 15 mm, and the upper 4 layers of the suspension coil 11 each have a diameter 5 mm larger than the lower layer. The distance between each layer of the suspension coil 11 is 4 mm, and the distance between the stabilizing coil 12 and the suspension coil 11 is 7 mm. The stabilizing coil 12 cooperates with the suspension coil 11 to effectively make the metal material stably suspended within a range of 7 mm between the stabilizing coil 12 and the suspension coil 11, thereby ensuring the stability of the evaporation process. In other embodiments, the suspension smelting evaporation coil 1 can also be designed to other specifications according to needs, which are not limited here.
[0039] The high-frequency power supply is connected to the suspension smelting evaporation coil 1 to form a closed loop, and the high-frequency power supply provides an alternating voltage. Specifically, the frequency range of the high-frequency power supply is 300-800kHz, and the power range is 50-100kW. The high-frequency power supply cooperates with the suspension smelting evaporation coil 1 to suspend, heat, melt and evaporate the metal material. As described above, the stabilizing coil 12 and the suspension coil 11 are integrally formed, and the high-frequency power supply can simultaneously power the stabilizing coil 12 and the suspension coil 11.
[0040] The liner 2 is a hollow sleeve disposed in the suspension smelting evaporation coil 1, and the suspension smelting evaporation coil 1 is wound on the outer wall of the liner 2. The liner 2 can prevent the metal material from sputtering or evaporating and condensing onto the coil during heating and evaporation, causing the coil to spark. In this embodiment, the liner 2 is a fused quartz hollow sleeve, which is resistant to high temperatures and has a small expansion coefficient. It can withstand the sputtering and evaporation and condensation of high-temperature metal materials during heating and evaporation without cracking; the shell is transparent, and the state of the metal material can be observed in real time. In other embodiments, the liner 2 can also be made of materials such as No. 4 high-temperature resistant glass, which is not limited here.
[0041] A water-cooled crucible 3 is provided at the bottom of the liner 2. When the evaporation is completed, the remaining material can fall into the water-cooled crucible 3 for recycling.
[0042] The bottom end of the liner 2 is provided with 3 to 6 vents 21, and the 3 to 6 vents 21 are connected to a high temperature resistant air inlet pipe (not shown). The suspended evaporation source also includes a gas ionization electrode (not shown) arranged outside the air inlet pipe, and a high voltage bias power supply (not shown) connected to the gas ionization electrode. Under the action of high frequency heating, high frequency magnetic field, and gas ionization electrode, the gas entering from the vent 21 is ionized. The ionized gas has high kinetic energy, which can take away impurities and gases attached to the surface of the metal material, further improving the purity of the material; at the same time, the introduced airflow can stabilize the position and stir the molten droplets, making it easier to remove impurities remaining on the metal material, and improving the film quality. In addition, the ionized gas has high energy, which can transfer energy to the metal molecules, increase their kinetic energy, and improve the evaporation efficiency. In this embodiment, there are 6 vents 21, and the 6 vents 21 are equidistantly distributed along the bottom edge of the liner 2, which will not generate horizontal force on the metal material, so that the metal material is stably suspended, ensuring the stability of the evaporation process. In other embodiments, the number of the vent holes 21 may be 3, 4 or 5, which is not specifically limited.
[0043] The evaporation deposition rate sensor (not shown) is arranged above the suspension smelting evaporation coil 1, and can monitor the evaporation rate of the metal material in real time. According to the detected evaporation rate, the output power of the high-frequency power supply is adjusted, so as to accurately adjust the evaporation rate of the metal material to ensure the stability of the material deposition film forming rate.
[0044] The suspension evaporation source also includes an automatic feeding arm 4 arranged above the liner 2, and the automatic feeding arm 4 includes a material guide rail 41 and an automatic unloading part 42 connected to the material guide rail 41. The metal material to be evaporated is placed in the suspension smelting evaporation coil 1 through the automatic feeding arm 4. The automatic unloading part 42 includes a ceramic clamp, which can clamp and fix a metal particle under the action of an electromagnet. When the material guide rail 41 rotates to the hopper 5 with the center hole as the axis, the ceramic clamp is just located at both ends of the metal ball. At this time, the electromagnet is turned on, and the ceramic clamp attracts and clamps the metal ball under the action of the electromagnet. Then the material guide rail 41 rotates back, and when the material guide rail 41 reaches the horizontal position, the clamp automatically opens, releases the metal ball, and the metal ball falls into the suspension smelting evaporation coil 1. When the ball is taken away from the bottom of the hopper 5, a new ball will fall in for the next feeding.
[0045] Furthermore, the suspension evaporation source uses any one or more of a variety of high-purity metals as coating materials. The various high-purity metals include Ag with a purity of >4N, Cu with a purity of >4N, Au with a purity of >4N, and Al with a purity of >5N. The coating material is a spherical particle of uniform size, and the particle size is slightly smaller than the width of the material guide rail 41, so that when adding materials, the metal particles are fixed to a fixed position by the material guide rail 41, while keeping the weight of each addition consistent.
[0046] The suspension evaporation source and the coating material are further described below in conjunction with specific embodiments.
[0047] Embodiment 1:
[0048] The suspension evaporation source is installed in the vacuum chamber of the coating machine, and connected to the high-frequency power supply and the corresponding control equipment; silver metal material pellets with a purity of >4N are loaded into the material bin, and the workpiece to be coated is installed on the workpiece plate of the coating machine; after cleaning the inside of the coating machine, the vacuum chamber is closed and vacuumized; the automatic feeding arm is started, and the metal material pellets are put into the suspension melting evaporation coil; the high-frequency power supply is started, and the metal material is stably suspended between the suspension coil and the stabilizing coil under the action of the suspension melting evaporation coil, and gradually heated up and melted; the vent is opened to allow Ar gas to spray out and form ions, further remove impurities on the metal surface, and improve the purity, and the vent is closed after 10 minutes; as the temperature rises to the evaporation temperature of metallic silver of about 1100°C, the metal droplets begin to evaporate, and at this time, the coil current can be controlled by detecting the rate of evaporation and deposition of the material, so that the evaporation rate is stabilized at the required value, and the deposition process of the metal film is completed; as the evaporation proceeds, new materials can be added according to the situation; when the film thickness reaches the requirement, the heating is stopped to end the evaporation process; when the evaporation is completed, the remaining material falls into a water-cooled crucible for recycling.
[0049] After the coating is completed, the coated workpiece is taken out and the reflectivity of the thin film reflective layer is checked. It can be found that the average reflectivity in the visible light band can reach more than 99%, which is significantly better than the traditional resistance evaporation or electron gun evaporation process. And compared with the traditional resistance evaporation or electron gun evaporation process, the properties of the metal material using the suspension vacuum evaporation process will not deteriorate with evaporation.
[0050] Embodiment 2:
[0051] The suspension evaporation source is installed in the vacuum chamber of the coating machine, and connected with a high-frequency power supply and corresponding control equipment; aluminum metal material pellets with a purity of >5N are loaded into the material bin, and the workpiece to be coated is installed on the workpiece plate of the coating machine; after cleaning the inside of the coating machine, the vacuum chamber is closed and vacuumized; the automatic feeding arm is started, and the metal material pellets are put into the suspension melting evaporation coil; the high-frequency power supply is started, and the metal material is stably suspended between the suspension coil and the stabilizing coil under the action of the suspension melting evaporation coil, and gradually heated up and melted; the vent is opened to allow Ar gas to spray out and form ions, further remove impurities on the metal surface, and improve the purity, and the vent is closed after 10 minutes; as the temperature rises to the evaporation temperature of metal aluminum of about 1200°C, the metal droplets begin to evaporate, and at this time, the coil current can be controlled by detecting the rate of evaporation and deposition of the material, so that the evaporation rate is stabilized at the required value, and the deposition process of the metal film is completed; as the evaporation proceeds, new materials can be added according to the situation; when the film thickness reaches the requirement, the heating is stopped to end the evaporation process; when the evaporation is completed, the remaining material falls into a water-cooled crucible for recycling.
[0052] After the coating is completed, the coated workpiece is taken out and the reflectivity of the thin film reflective layer is checked. It can be found that the average reflectivity in the visible light band can reach more than 92%, which is significantly better than the traditional resistance evaporation or electron gun evaporation process. And compared with the traditional resistance evaporation or electron gun evaporation process, the properties of the metal material using the suspension vacuum evaporation process will not deteriorate with evaporation.
[0053] In summary, the present invention sets a suspension melting evaporation coil and a high-frequency power supply coordinated therewith, so that an induced current that can heat the metal material and a new magnetic field are generated inside the metal material. The new magnetic field cooperates with the magnetic field of the suspension coil and the magnetic field of the stabilizing coil to suspend the metal material in the air, and then heats and evaporates the high-purity metal material by vacuum suspension heating; the coating material used is high-purity metal beads with consistent particle size, the weight of each feed is consistent, the amount of each feed is fixed, and the coating rate is stable; the high-purity metal material is stably suspended between the suspension coil and the stabilizing coil during the melting process, avoiding various contaminations caused by material contact, maintaining the high purity of the material itself, and thus the formed film will have higher optical properties; an inner liner is placed inside the suspension melting evaporation coil to prevent the metal material from sputtering or evaporating and condensing onto the coil during heating and evaporation, causing the coil to spark; the suspension evaporation source has a simple structure, high film quality, and strong application value.
[0054] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0055] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.
Claims
1. A suspended evaporation source for preparing high-purity metal thin films, arranged in a vacuum chamber of a coating machine, characterized in that: include: The suspension smelting evaporation coil comprises a suspension coil spirally wound in the same direction away from each other along the axis direction, and a stabilizing coil arranged above the suspension coil and having a current direction opposite to that of the suspension coil; A high-frequency power supply is connected to the suspension smelting evaporation coil to form a closed loop, and the high-frequency power supply provides an alternating voltage; The liner is a hollow sleeve arranged in the suspension smelting evaporation coil, the suspension smelting evaporation coil is wound on the outer wall of the liner, 3 to 6 ventilation holes are opened on the bottom of the liner, and the 3 to 6 ventilation holes are connected to high temperature resistant air inlet pipes; The suspension coil has 4 to 7 layers and the spacing between every two layers is equal. The diameters of the bottom 2 to 3 layers of the suspension coil are the same, and the diameters of the upper 2 to 4 layers gradually increase. The stabilizing coil is integrally formed with the suspension coil but is wound in opposite directions. The diameter of the stabilizing coil is consistent with the diameter of the uppermost layer of the suspension coil. The spacing between the stabilizing coil and the uppermost layer of the suspension coil is greater than the spacing between every two layers of the suspension coil. The stabilizing coil cooperates with the suspension coil to allow the metal material to stably suspend between the stabilizing coil and the suspension coil.
2. A suspension evaporation source for preparing a high-purity metal film as claimed in claim 1, characterized in that: The suspension evaporation source further includes an evaporation deposition rate sensor disposed above the suspension smelting evaporation coil.
3. A suspension evaporation source for preparing a high-purity metal film according to claim 1, characterized in that: The frequency range of the high-frequency power supply is 300-800kHz, and the power range is 50-100kW.
4. A suspension evaporation source for preparing a high-purity metal film according to claim 1, characterized in that: The suspension coil has 7 layers, the lower 3 layers of the suspension coil have the same diameter and an inner diameter of 15 mm, the upper 4 layers of the suspension coil each have a diameter 5 mm larger than the lower layer, the distance between each layer of the suspension coil is 4 mm, and the distance between the stabilizing coil and the suspension coil is 7 mm.
5. A suspension evaporation source for preparing a high-purity metal film according to claim 1, characterized in that: The suspension evaporation source further includes a gas ionization electrode arranged outside the air inlet pipe, and a high-voltage bias power supply connected to the gas ionization electrode.
6. A suspension evaporation source for preparing a high-purity metal film as claimed in claim 1, characterized in that: The inner lining is a fused quartz hollow sleeve.
7. A suspension evaporation source for preparing a high-purity metal film according to claim 1, characterized in that: A water-cooled crucible for recovering coating materials is arranged at the bottom of the inner liner.
8. A suspension evaporation source for preparing a high-purity metal film as claimed in claim 1, characterized in that: There are six ventilation holes, and the six ventilation holes are evenly distributed along the bottom edge of the lining.
9. A suspension evaporation source for preparing a high-purity metal film according to claim 1, characterized in that: The suspension evaporation source further comprises an automatic feeding arm arranged above the liner, and the automatic feeding arm comprises a material guide rail and an automatic unloading part connected to the material guide rail.