CN216039797U

CN216039797U - Magnetic control cathode structure for physical vapor deposition machine

Info

Publication number: CN216039797U
Application number: CN202121746301.0U
Authority: CN
Inventors: 林先展
Original assignee: CPT Technology Group Co Ltd
Current assignee: CPT Technology Group Co Ltd
Priority date: 2021-07-29
Filing date: 2021-07-29
Publication date: 2022-03-15
Anticipated expiration: 2031-07-29

Abstract

The utility model discloses a magnetic control cathode structure for a physical vapor deposition machine, which comprises a cathode back plate, wherein the front surface of the cathode back plate corresponding to a target material is a smooth plane, a plurality of cooling liquid channels are arranged at intervals in the back surface of the cathode back plate, and magnetic fluid with set concentration flows in the cooling liquid channels. Through set up the coolant liquid passageway in negative pole copper backplate inside, the coolant liquid of coolant liquid passageway adopts magnetic fluid, and magnetic fluid flows in cooling tube inside and takes away the heat that produces when sputtering target, prevents that the target from leading to metal indium to melt and break away from the copper backplate because overheated to magnetic fluid possesses and forms the high-intensity magnetic field, and along with magnetic fluid flows in the inside stability of pipeline, forms the magnetic field the same with bar magnet magnetic field direction and magnetic field intensity, plays the direction of adjusting the target particle rotation and the position of motion, makes it deposit on glass substrate evenly. The magnetic field size of the utility model can realize adjustability according to actual requirements, and the adjustment of the film uniformity is satisfied.

Description

Magnetic control cathode structure for physical vapor deposition machine

Technical Field

The utility model relates to the technical field of display, in particular to a magnetic control cathode structure for a physical vapor deposition machine.

Background

The Organic Light Emitting Diode (Organic Light Emitting Diode) OLED display has the characteristics of low power consumption, wide viewing angle, high response speed, ultra-Light weight, thinness, good shock resistance and the like, and is developed more and more rapidly as an autonomous Light Emitting device in a high-performance display area;

at present, a circuit thin film material in a TFT driving module in an OLED display is mostly prepared by PVD (physical vapor deposition), which is also referred to as magnetron sputtering for short, and the principle of the PVD is that ions with charges are accelerated in an electromagnetic field to guide ions with high kinetic energy to a target made of a sputtered substance, and after the incident ions collide with atoms on the surface of the target, the target atoms are sputtered out and emitted to a glass substrate along a certain direction, so that a thin film is formed on the surface of the glass substrate.

The cathode structure of a PVD (physical vapor deposition) machine comprises a cathode magnet, a target and a copper back plate for bearing the target, wherein the magnet is used for adjusting the movement path of target particles, so that the thickness of a deposited film is more uniform. As shown in fig. 1, a magnet 2 in the conventional scheme is disposed on the back of a cathode backplate, the magnet 2 is fixedly and orderly arranged on the back of the cathode backplate, fig. 2 is a structure of a magnetron sputtering chamber 5, and the preparation principle is that an RF power supply is added on an anode glass substrate 4 and a cathode target 3 to excite Ar to form Ar + and an electron e, wherein charged Ar + ions are accelerated in an electromagnetic field, ions with high kinetic energy are introduced to the sputtered target 3, after the incident ions collide with atoms on the surface of the target 3, the atoms of the target 3 are sputtered out and directed to the glass substrate 4 along a certain direction, so as to form a uniform thin film on the surface of the glass substrate as shown in fig. 2; the magnet 2 adjusts the moving path of the target 3 particles, so that the thickness of the deposited film is more uniform, but the magnetic field and the position of the cathode magnet are fixed. As shown in fig. 3, when the target 3 is sputtered for a while, the target 9 without starting sputtering has an uneven profile structure on the surface of the target 3, and the target 10 after sputtering includes a target convex region 11 after sputtering and a target concave region 12 after sputtering as shown in fig. 4. Therefore, the utilization rate of the target 3 is less than 30%, the uniformity of the film thickness of the film sputtered in the later period is poor, the production requirement cannot be met, and the material of the target 3 is wasted.

Disclosure of Invention

The utility model aims to provide a magnetron cathode structure for a physical vapor deposition machine.

The technical scheme adopted by the utility model is as follows:

a magnetic control cathode structure for a physical vapor deposition machine comprises a cathode back plate, wherein the front face of the cathode back plate corresponding to a target 3 is a smooth plane, a plurality of cooling liquid channels are arranged at intervals in the back face of the cathode back plate, and magnetic fluid with set concentration flows through the cooling liquid channels.

Further, the cooling liquid channel is a U-shaped channel.

Furthermore, two ends of the cooling liquid channel are respectively provided with a liquid inlet pipe orifice and a liquid outlet pipe orifice.

Furthermore, the openings of the liquid inlet pipe orifice and the liquid outlet pipe orifice are positioned on the back surface of the cathode back plate.

Further, magnetic fluid with different concentrations flows in each cooling liquid channel, or magnetic fluid with the same concentration flows in the cooling liquid channels.

Further, the concentration of the magnetic fluid in the cooling liquid channel differs according to the sputtering magnetic field strength requirement of the corresponding target 3.

Further, the magnetic fluid comprises a base carrier liquid, a surfactant and nano-scale magnetic solid particles,

further, as the magnetic solid particles, Ni magnetic particles and Co magnetic particles are used, and the magnetic solid particles are not limited to Ni, Co, and the like.

Further, the base carrier fluid is one or a combination of two or more of water, an organic solvent, oil and a coolant, but is not limited thereto.

Further, the surfactant is oleic acid.

According to the technical scheme, the cooling liquid channel is arranged in the cathode copper back plate, the cooling liquid of the cooling liquid channel adopts the magnetic fluid, the magnetic fluid flows in the cooling pipeline, so that the heat generated during sputtering of the target 3 is brought out, the target 3 is prevented from being separated from the copper back plate due to melting of metal indium caused by overheating, the magnetic fluid forms a strong magnetic field, a magnetic field with the same direction as the magnetic field of the bar-shaped magnet and the same magnetic field strength is formed along with the stable flow of the magnetic fluid in the pipeline, and the magnetic field is used for adjusting the rotating direction and the moving position of particles of the target 3 to enable the particles to be uniformly deposited on the glass substrate. The magnetic field size of the utility model can realize adjustability according to actual requirements, not only can meet the adjustment of the uniformity of the film, but also can improve the service life of the target 3, reduce the production cost and realize energy conservation and emission reduction of factories.

Drawings

The utility model is described in further detail below with reference to the accompanying drawings and the detailed description;

FIG. 1 is a schematic structural view of a conventional magnet disposed on the back surface of a cathode back plate;

FIG. 2 is a schematic structural diagram of a magnetron sputtering chamber 5 according to a conventional scheme;

FIG. 3 is a schematic view of the target 9 without starting sputtering;

fig. 4 is a schematic view of the surface structure of the target 3 sputtered for a period of time;

FIG. 5 is a schematic structural view of a magnetron cathode used in a PVD equipment of the utility model;

fig. 6 is a schematic diagram of the distribution structure of the cooling liquid channel of the present invention.

Reference numerals: 1. a cathode backing plate; 2. a magnet; 3. a target material 3; 4. a glass substrate; 5. a cavity; 6. a coolant passage; 7. a liquid inlet pipe orifice; 8. a liquid outlet pipe opening 9 for discharging the target material before sputtering; 10. sputtering the target material; 11. a target material convex area after sputtering; 12. and (4) a target depression area after sputtering.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application.

As shown in fig. 5 or fig. 6, the present invention discloses a magnetron cathode structure for a physical vapor deposition machine, including a cathode backplate 1, wherein the cathode backplate 1 is formed by a metal copper material, the front surface of the cathode backplate 1 corresponding to a target 3 is a smooth plane, a plurality of cooling liquid channels 6 are arranged at intervals inside the back surface of the cathode backplate 1, and a magnetic fluid with a set concentration flows through the cooling liquid channels 6.

Further, the coolant passage 6 is a U-shaped passage.

Further, two ends of the cooling liquid channel 6 are respectively provided with a liquid inlet pipe orifice 7 and a liquid outlet pipe orifice 8.

Further, the openings of the liquid inlet pipe orifice 7 and the liquid outlet pipe orifice 8 are positioned on the back surface of the cathode back plate 1.

Further, magnetic fluid of different concentrations flows through each of the cooling liquid channels 6, or magnetic fluid of the same concentration flows through the cooling liquid channels 6.

Further, the concentration of the magnetic fluid in the cooling liquid channel 6 differs according to the sputtering magnetic field strength requirement of the corresponding target 3.

Specifically, the intensity of the magnetic field generated by the magnetic fluid is controlled by controlling the flowing concentration of the magnetic fluid in the cooling pipeline, and the unevenness appears in the partial area of the target 3 according to the fact that the sputtering time of the target 3 is longer and longer; for the concave part of the target 3, the concentration of the magnetic fluid in the concave part of the target 3 can be reduced, the magnetic field intensity in the region can be reduced, and then the emergence rate of the target 3 particles in the region can be reduced, for the convex part of the target 3, the flow rate of the magnetic fluid in the convex part of the target 3 can be improved, the magnetic field intensity in the region can be increased, and further the emergence rate of the target particles in the region can be increased.

Furthermore, a particle film filter is arranged at one end of the cooling liquid channel 6, part of magnetic substances are selectively filtered through the particle film filter, the concentration of the magnetic fluid in the mixed liquid of the magnetic fluid and the cooling liquid is optimally adjusted, the magnetic field intensity of the corresponding area is reasonably adjusted, the particle emergence rate of the area of the target 3 is reasonably coordinated, the rotating position of particles is reasonably controlled, the utilization rate of the target 3 is improved, and the uniformity of a film deposited on the glass substrate 4 is also improved. In addition, it should be noted that the cooling rate of the target 3 is controlled by controlling the flow rate of the magnetic fluid flowing in the cooling liquid pipeline, and the flow rate of the magnetic fluid does not affect the concentration of the magnetic fluid, so that the magnetic field strength and the magnetic field direction at the cathode back plate 1 are not affected by controlling the flow rate of the magnetic fluid, so that the sputtering temperature of the target 3 can be optimized by controlling the flow rate of the magnetic fluid, and the risk of the target 3 falling off the target is avoided.

Furthermore, the magnetic fluid has both liquid fluidity and magnetism of a solid magnetic material, and the composition of the magnetic fluid is a stable colloidal liquid formed by mixing magnetic solid particles with the diameter of nanometer level (below 10 nanometers), a base carrier liquid (also called a medium) and a surfactant. The magnetic solid particles in the magnetic fluid are not limited to magnetic particles such as Ni and Co, the base carrier fluid is not limited to water, organic solvent, oil, cooling liquid and the like, and oleic acid is used as an active agent to prevent agglomeration, so that the magnetic fluid not only has liquid fluidity and solid magnetism, but also has excellent heat conduction media such as water, organic solvent and oil in the base carrier fluid, and can transfer heat generated by the target 3 to regulate the temperature of the target 3 and prevent the target 3 from falling off.

According to the technical scheme, the cooling liquid channel 6 is arranged in the cathode copper back plate, the cooling liquid of the cooling liquid channel 6 is the magnetic fluid, the magnetic fluid flows in the cooling pipeline, so that heat generated during sputtering of the target 3 is taken out, the target 3 is prevented from being separated from the copper back plate due to melting of metal indium caused by overheating, the magnetic fluid forms a strong magnetic field, a magnetic field which is the same as the direction of a bar-shaped magnet magnetic field and the magnetic field intensity is formed along with stable flowing of the magnetic fluid in the pipeline, and the magnetic field is used for adjusting the rotating direction and the moving position of particles of the target 3 to enable the particles to be uniformly deposited on the glass substrate 4. The magnetic field size of the utility model can realize adjustability according to actual requirements, not only can meet the adjustment of the uniformity of the film, but also can improve the service life of the target 3, reduce the production cost and realize energy conservation and emission reduction of factories.

It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. The embodiments and features of the embodiments in the present application may be combined with each other without conflict. The components of the embodiments of the present application, generally described and illustrated in the figures herein, can be arranged and designed in a wide variety of different configurations. Thus, the detailed description of the embodiments of the present application is not intended to limit the scope of the claimed application, but is merely representative of selected embodiments of the application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Claims

1. A magnetic control cathode structure for a physical vapor deposition machine is characterized in that: the cathode back plate comprises a cathode back plate, wherein the front surface of the cathode back plate corresponding to a target material is a smooth plane, a plurality of cooling liquid channels are arranged at intervals in the back surface of the cathode back plate, and magnetic fluid with set concentration flows in the cooling liquid channels.

2. The magnetron cathode structure of claim 1, wherein the magnetron cathode structure comprises: the cooling liquid channel is a U-shaped channel.

3. The magnetron cathode structure of claim 1, wherein the magnetron cathode structure comprises: the two ends of the cooling liquid channel are respectively provided with a liquid inlet pipe orifice and a liquid outlet pipe orifice.

4. The magnetron cathode structure of claim 3, wherein the magnetron cathode structure comprises: the openings of the liquid inlet pipe orifice and the liquid outlet pipe orifice are positioned on the back surface of the cathode back plate.

5. The magnetron cathode structure of claim 1, wherein the magnetron cathode structure comprises: magnetic fluid with different concentrations flows in each cooling liquid channel, or magnetic fluid with the same concentration flows in the cooling liquid channels.

6. The magnetron cathode structure of claim 1, wherein the magnetron cathode structure comprises: the concentration of the magnetic fluid in the cooling liquid channel is different according to the different requirements of the sputtering magnetic field strength of the corresponding target.

7. The magnetron cathode structure of claim 1, wherein the magnetron cathode structure comprises: the magnetic fluid comprises base carrier liquid, surfactant and nano-scale magnetic solid particles.

8. The magnetron cathode structure of claim 7, wherein: the magnetic solid particles adopt Ni magnetic particles and Co magnetic particles.

9. The magnetron cathode structure of claim 7, wherein: the base carrier fluid adopts one or the combination of more than two of water, organic solvent, oil and cooling fluid.

10. The magnetron cathode structure of claim 7, wherein: the surfactant is oleic acid.