Multi-channel vacuum evaporation source

Abstract

The present invention provides a multi-channel vacuum evaporation source, which comprises: a plurality of independent evaporation channels, which are configured to provide evaporation operations for coating objects respectively; an integrated cover, which is configured to integrate the top ends of the plurality of independent evaporation channels in a closed space, and the plurality of independent evaporation channels transmit evaporated target materials to the coating objects through their top ends; a combined baffle, which is configured to be located between the integrated cover and the coating object, and to connect or isolate the plurality of independent evaporation channels from the coating object through opening and closing actions; a mounting flange, which is configured to integrate the plurality of independent evaporation channels with a baffle drive; and the baffle drive is configured to control and drive the opening and closing actions of the combined baffle.

Description

Technical Field

[0001] The invention relates to the field of semiconductor technology, and in particular to a multi-channel vacuum evaporation source. Background Art

[0002] In the production process of semiconductor integrated circuits, sensors and solar panels, many structures require vacuum coating technology to generate. Therefore, vacuum coating directly determines the quality of products such as semiconductors and solar panels. The research and application of vacuum coating are inseparable from its production equipment, so the research and development of evaporation sources is of great significance.

[0003] At present, the main vacuum coating technologies at home and abroad include vacuum evaporation coating, vacuum sputtering coating, and vacuum ion coating, among which vacuum evaporation coating is the most widely used. Vacuum evaporation coating technology is to evaporate the film material (such as metal or compound) by heating it in a high vacuum or ultra-high vacuum chamber through an evaporation source. The evaporated particles escape from the surface of the film material. When the mean free path of the evaporated molecules is greater than the linear dimension between the evaporation source and the substrate, they can directly reach the substrate surface and condense to form a film.

[0004] The principle of electron beam heating evaporation source is based on the fact that the kinetic energy obtained by electrons under the action of electric field is converted into heat energy for heating, thereby achieving heating, evaporation and condensation of film materials into the required film. It is mainly composed of cathode, anode, bunching pole and magnetic field for providing electrons. The characteristics of electron beam heating source are concentrated energy, which can make the surface of film material quickly reach extremely high temperature, the film material evaporation rate and film deposition rate are high, it can be cooled by water, and the temperature range can be adjusted. At present, most electron beam heating evaporation sources use high-temperature electrons to bombard film materials and melt metals (or compounds) with huge energy, then evaporate and coat them. The specific steps include: energizing the filament, heating the filament, and generating hot electrons. The filament is grounded and is at ground potential. The evaporation rod / crucible is about 5-10mm away from the filament, and the evaporation rod / crucible is connected to positive high voltage (for example, +800V). Under the action of the electric field, the electrons are accelerated and bombard the top of the evaporation rod / crucible, and the evaporation rod / crucible is heated by the high-energy electron beam. The evaporation rod / target material in the crucible is heated, evaporated, and deposited on the substrate. The beam current monitoring device monitors the growth beam current in real time. The evaporation rod assembly needs to have a linear moving assembly for adjusting the distance between the top of the evaporation rod and the filament.

[0005] The main factors affecting the performance of evaporation coating are evaporation rate, residual gas and evaporation temperature. The evaporation rate directly determines the quality of the film. The corresponding film material corresponds to the corresponding evaporation rate and deposition rate. Compared with other coating methods, evaporation coating has a higher deposition rate and can evaporate most metal and compound films. When the coating process requires multiple metals or compounds to form the film material / target material, it is difficult to control different materials separately at the same time to meet the process requirements. Summary of the invention

[0006] The object of the present invention is to provide a multi-channel vacuum evaporation source to solve the problem that the process of the existing coating process is difficult to control due to the complex composition of the film material.

[0007] In order to solve the above technical problems, the present invention provides a multi-channel vacuum evaporation source, which comprises:

[0008] A plurality of independent evaporation channels are configured to provide evaporation operations for the coating objects respectively;

[0009] An integrated cover is configured to integrate the top ends of the plurality of independent evaporation channels in a closed space, and the plurality of independent evaporation channels transmit evaporated target materials to the coating object through the top ends thereof;

[0010] A combined baffle is configured to be located between the integrated cover and the coating object, and connects or isolates the plurality of independent evaporation channels from the coating object through opening and closing actions;

[0011] A baffle drive, configured to control and drive the opening and closing actions of the combined baffle;

[0012] a mounting flange configured to integrate the plurality of independent evaporation channels with the baffle drive;

[0013] The combined baffle includes a first baffle and a second baffle, and the baffle drive includes a first transmission rod and a second transmission rod, wherein:

[0014] The second transmission rod is a hollow structure, and the first transmission rod is wrapped in the second transmission rod; the first transmission rod and the second transmission rod are located at the center of the integrated cover and integrated in the mounting flange;

[0015] One end of the first transmission rod is connected to the first baffle plate to transmit torque between the first baffle plates;

[0016] One end of the second transmission rod is connected to the second baffle plate to transmit torque between the second baffle plates;

[0017] The integrated cover partition is placed in the cylindrical space in the middle of the integrated cover, dividing the cylindrical space into three equal parts, and a filament assembly is placed in each equal part. The partition base is supported on the base, and there are three grooves at an angle of 120° on the partition base for clamping the partition therein;

[0018] The copper module and the ceramic module are used to fix the filament assembly formed by the filament and the molybdenum rod; the molybdenum rod is fixed to the ceramic module by brazing, and the ceramic module is made of ceramic to insulate the filament from the ground;

[0019] The copper module is made of copper and is fixed together with the integrated cover to form a cooling closed space. The crucible and the target are located in the cooling closed space. After the crucible and the target are heated, the radiated heat is absorbed by the integrated cover, the partition, the copper module and the base to prevent heating of other components in the vacuum chamber.

[0020] Optionally, in the multi-channel vacuum evaporation source, the states between the multiple groups of independent evaporation channels and the coating object include:

[0021] The plurality of independent evaporation channels are all connected to the coating object;

[0022] The multiple groups of independent evaporation channels are isolated from the coating object;

[0023] One or more of the plurality of independent evaporation channels are in communication with the coating object;

[0024] One or more of the plurality of independent evaporation channels are separated from the coating object.

[0025] Optionally, in the multi-channel vacuum evaporation source, the combined baffle includes a first baffle and a second baffle, wherein:

[0026] The first baffle plate and the second baffle plate are stacked, the bottom surface of the second baffle plate faces the tops of the multiple groups of independent evaporation channels, and the top surface of the first baffle plate faces the coating object;

[0027] The first baffle plate and the second baffle plate both have a plurality of openings;

[0028] The number of the openings is set according to the number of the independent evaporation channels;

[0029] When the opening of the first baffle plate and the opening of the second baffle plate overlap above the top of a certain independent evaporation channel, the independent evaporation channel is connected to the coating object; otherwise, the independent evaporation channel is separated from the coating object.

[0030] Optionally, in the multi-channel vacuum evaporation source, each group of independent evaporation channels includes a filament, a crucible, a crucible support, a moving device and a high-voltage source interface, wherein:

[0031] The filament is placed above the crucible and fixedly connected to the integrated cover;

[0032] The opening of the crucible faces the top of the independent evaporation channel where it is located, and the crucible support is fixed below the crucible and extends outside the integrated cover;

[0033] The mounting flange clamps a plurality of the crucible supports;

[0034] The moving device is fixed below the mounting flange and passes through the mounting flange to be connected to the crucible support. The moving device adjusts the length of the crucible support to adjust the distance between the crucible and the filament.

[0035] The high voltage source interface is located below the moving device and passes through the moving device to be connected to the crucible support. The high voltage source interface provides a positive voltage to the crucible through the crucible support.

[0036] Optionally, in the multi-channel vacuum evaporation source, the integrated cover has a water cooling function, wherein:

[0037] The integrated cover comprises an inner wall and an outer wall, the inner wall wraps the outer surface of the heat insulation layer, the outer wall and the inner wall are in a concentric cylindrical structure, and a coolant is accommodated between the inner wall and the outer wall.

[0038] Optionally, in the multi-channel vacuum evaporation source, the integrated cover further includes a base, and the base supports the integrated cover.

[0039] Optionally, in the multi-channel vacuum evaporation source, the baffle drive includes a magnetic coupling driver, a first transmission rod and a second transmission rod, wherein:

[0040] The second transmission rod is a hollow structure, and the first transmission rod is wrapped in the second transmission rod; the first transmission rod and the second transmission rod pass through the mounting flange and extend to the bottom of the moving device;

[0041] One end of the first transmission rod is connected to the first baffle, and the other end is connected to the magnetic coupling driver, so as to transmit torque between the magnetic coupling driver and the first baffle;

[0042] One end of the second transmission rod is connected to the second baffle, and the other end is connected to the magnetic coupling driver, so as to transmit torque between the magnetic coupling driver and the second baffle.

[0043] Optionally, in the multi-channel vacuum evaporation source, the number of the independent evaporation channels is 3, the three independent evaporation channels are evenly distributed at 120 degrees, and one of the first baffle and the second baffle has 4 openings, and the other has 5 openings.

[0044] In the multi-channel vacuum evaporation source provided by the present invention, evaporation operations are provided to the coating object respectively through multiple groups of independent evaporation channels, the integrated cover integrates the top ends of the multiple groups of independent evaporation channels in a closed space, and the multiple groups of independent evaporation channels transmit evaporated target materials to the coating object through their top ends. The combined baffle is located between the integrated cover and the coating object, and the multiple groups of independent evaporation channels are connected or isolated from the coating object through opening and closing actions. The mounting flange integrates the multiple groups of independent evaporation channels with the baffle drive, and the baffle drive controls and drives the opening and closing actions of the combined baffle, so that multiple different evaporation sources can provide different process conditions to the coating object according to the film material / target material, either simultaneously or in different time periods. Each independent evaporation channel can be adjusted according to different materials, different process steps, and different process conditions (voltage, time or evaporation rate, etc.), so that the entire process flow is simple and easy to operate, and flexible and changeable, so that the product quality of the coating object is guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figures 1 to 9 This is a schematic diagram of the structure of a multi-channel vacuum evaporation source according to an embodiment of the present invention;

[0046] As shown in the figure: 1-independent evaporation channel; 2-integrated cover; 3-combined baffle; 4-mounting flange; 5-baffle drive; 6-first baffle; 7-second baffle; 8-opening; 9-top of independent evaporation channel; 10-molybdenum rod; 11-crucible; 12-crucible support; 13-moving device; 14-high voltage source interface; 15-magnetic coupling drive; 16-first transmission rod; 17-second transmission rod; 18-baffle base bolt hole; 191-copper module; 192 ceramic module; 20-inner wall; 21-outer wall; 22-tube-mounted shielding cover; 23-cooling liquid delivery pipeline; 24-base; 25-integrated cover partition; 26-partition base; 27-stable ceramic; 28-stable ceramic fixings. DETAILED DESCRIPTION

[0047] The following is a further detailed description of the multi-channel vacuum evaporation source proposed by the present invention in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the present invention will become more apparent from the following description and claims. It should be noted that the accompanying drawings are all in a very simplified form and are not in precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention.

[0048] The core idea of ​​the present invention is to provide a multi-channel vacuum evaporation source to solve the problem that the existing coating process is difficult to control due to the complex composition of the film material.

[0049] To realize the above idea, the present invention provides a multi-channel vacuum evaporation source, which includes: multiple groups of independent evaporation channels, which are configured to provide evaporation operations for the coating objects respectively; an integrated cover, which is configured to integrate the top ends of the multiple groups of independent evaporation channels in a closed space, and the multiple groups of independent evaporation channels transfer the evaporated target materials to the coating objects through their top ends; a combined baffle, which is configured to be located between the integrated cover and the coating object, and through opening and closing actions, the multiple groups of independent evaporation channels are connected or isolated from the coating object; a mounting flange, which is configured to integrate the multiple groups of independent evaporation channels with a baffle drive; and the baffle drive is configured to control and drive the opening and closing actions of the combined baffle.

[0050] <Example 1>

[0051] The present embodiment provides a multi-channel vacuum evaporation source, which includes: a plurality of independent evaporation channels 1, which are configured to provide evaporation operations for the coating object respectively; an integrated cover 2, which is configured to integrate the top ends 9 of the plurality of independent evaporation channels 1 in a closed space, and the plurality of independent evaporation channels 1 transmit the evaporated target material to the coating object through the top ends 9; a combined baffle 3, which is configured to be located between the integrated cover 2 and the coating object, and to connect or isolate the plurality of independent evaporation channels 1 from the coating object through opening and closing actions; a mounting flange 4, which is configured to integrate the plurality of independent evaporation channels 1 with a baffle drive; another function of the mounting flange is to serve as a standard mounting interface to install the multi-channel vacuum evaporation source on other systems (e.g., a vacuum chamber). The baffle drive 5 is configured to control and drive the opening and closing actions of the combined baffle 3.

[0052] like Figure 7 As shown, in the multi-channel vacuum evaporation source, the connection states between the multiple groups of independent evaporation channels 1 and the coating object include: the multiple groups of independent evaporation channels 1 are all connected to the coating object; the multiple groups of independent evaporation channels 1 are all isolated from the coating object; one or more of the multiple groups of independent evaporation channels 1 are connected to the coating object; one or more of the multiple groups of independent evaporation channels 1 are isolated from the coating object.

[0053] like Figure 2 As shown, in the multi-channel vacuum evaporation source, the combined baffle 3 includes a first baffle 6 and a second baffle 7, wherein: the first baffle 6 and the second baffle 7 are superimposed, the bottom surface of the second baffle 7 faces the top 9 of the plurality of independent evaporation channels 1, and the top surface of the first baffle 6 faces the coating object; Figures 5-6As shown, the first baffle plate 6 and the second baffle plate 7 each have a plurality of openings 8; the number of the openings 8 is set according to the number of the independent evaporation channels 1; Figure 2 , 7 As shown, when the opening 8 of the first baffle 6 and the opening 8 of the second baffle 7 overlap above the top 9 of a certain independent evaporation channel 1, the independent evaporation channel 1 is connected to the coating object, otherwise the independent evaporation channel 1 is separated from the coating object.

[0054] like Figure 2 As shown, the molybdenum rod 10 is used to fix the filament (not shown in the figure). The copper module 191 and the ceramic module 192 are used to fix the filament assembly formed by the filament and the molybdenum rod 10. The molybdenum rod 10 is fixed to the ceramic module 192 by brazing. Since the ceramic module 192 is made of ceramic, the filament can be insulated from the ground. The copper module 191 is made of copper, and its main function is to be fixed together with the integrated cover 2 to form a cooling closed space. The crucible / target material is in the cooling closed space. After the crucible / target material is heated, most of the radiated heat is absorbed by the integrated cover 2, the upper copper module 192, and the lower base 24 to prevent the heat from being dissipated and heating other components in the vacuum chamber, causing the temperature of the components to rise and release gas, affecting the vacuum. The tube-mounted shielding cover 22 is a shielding cover / protective cover used to wrap the filament wiring connector, Figure 2 It can be seen that the molybdenum rod 10 is bent into an L shape, and the short rod part at the top that is perpendicular to the axial direction is used to connect to the power supply cable. The function of the tubular shielding cover 22 is to wrap up this connection component and play a certain protective role (to prevent other evaporation sources in the system from evaporating and coating when the material grows on the connection component and causes a short circuit).

[0055] like Figure 1 , 2As shown in , 3, in the multi-channel vacuum evaporation source, each group of independent evaporation channels 1 includes a filament (not shown in the figure), a molybdenum rod 10, a crucible 11, a crucible support 12, a moving device 13 and a high-voltage source interface 14, wherein: the molybdenum rod 10 (connected with the filament to form a filament assembly) is placed above the crucible 11, and is fixedly connected to the tubular shielding cover 22 in the integrated cover 2, the tubular shielding cover 22 and the combined baffle base are fixedly connected through the baffle base bolt holes 18, a plurality of crucibles 11 are integrated into a module formed by the integrated cover 2, and the tubular shielding cover 22 is fixedly connected to the integrated cover 2; the opening of the crucible 11 faces the top 9 of the independent evaporation channel 1 where it is located, the crucible support 12 is fixed below the crucible 11, and extends to the outside of the integrated cover 2, or the The integrated cover 2 also includes a base 24, which is used to fix multiple crucible supports 12. The base 24 clamps a stable ceramic 27, and the stable ceramic 27 clamps the crucible support 12 (made of molybdenum rod); the base 24 extending from the crucible support 12 is then integrated by the mounting flange 4; the moving device 13 is fixed under the mounting flange 4 and connected to the crucible support 12 through the mounting flange 4, and the moving device 13 adjusts the length of the crucible support 12 to adjust the distance between the crucible 11 and the molybdenum rod 10; the high-voltage source interface 14 is located under the moving device 13 and connected to the crucible support 12 through the moving device 13, and the high-voltage source interface 14 provides a positive voltage to the crucible 11 through the crucible support 12.

[0056] like Figure 2 As shown, in the multi-channel vacuum evaporation source, the integrated cover 2 has a water cooling function, wherein: the integrated cover 2 includes an inner wall 20 and an outer wall 21, the outer wall 21 and the inner wall 20 are in a concentric cylindrical structure, and a cooling liquid is contained between the inner wall 20 and the outer wall 21. Figure 1 As shown, two cooling liquid delivery pipelines 23 inject cooling liquid into the space between the inner wall 20 and the outer wall 21, or guide cooling liquid out, and the two cooling liquid delivery pipelines 23 are one for input and one for output. In the multi-channel vacuum evaporation source, the base 24 is also used to carry the integrated cover.

[0057] like Figure 1 , 2As shown in , 4, in the multi-channel vacuum evaporation source, the baffle drive 5 includes a magnetic coupling drive 15, a first transmission rod 16 and a second transmission rod 17, wherein: the second transmission rod 17 is a hollow structure, and the first transmission rod 16 is wrapped in the second transmission rod 17; the first transmission rod 16 and the second transmission rod 17 pass through the mounting flange 4 and extend to the bottom of the moving device 13; one end of the first transmission rod 16 is connected to the first baffle 6, and the other end is connected to the magnetic coupling drive 15, for transmitting torque between the magnetic coupling drive 15 and the first baffle 6; one end of the second transmission rod 17 is connected to the second baffle 7, and the other end is connected to the magnetic coupling drive 15, for transmitting torque between the magnetic coupling drive 15 and the second baffle 7.

[0058] like Figure 3 , 4 As shown, in the multi-channel vacuum evaporation source, the number of the independent evaporation channels 1 is 3, and the three independent evaporation channels 1 are evenly distributed at 120 degrees. Accordingly, one of the first baffle 6 and the second baffle 7 has 4 openings 8 and the other has 5 openings 8.

[0059] like Figure 8 As shown, the integrated cover spacer ring 25 is placed in the cylindrical space in the middle of the integrated cover, dividing the cylindrical space into three equal parts, and placing an evaporation source assembly in each part. In this way, the heat radiated by the heated crucible / evaporation rod will be taken away by the integrated cover, preventing other parts in the heating system from affecting the system vacuum. Figure 3 As shown, the partition base 26 is supported on the base 24, and there are three grooves with an angle of 120° on the partition base 6 for clamping the partition 25 therein.

[0060] like Fig. 9 As shown, there is a beam detection device 102 in the path between the crucible / evaporation rod 104 and the substrate 101, and its structure is a ring. The filament 103 is energized to emit thermal electrons. The filament 103 is grounded, and the crucible / evaporation rod 104 is connected to high voltage. Under the action of the electric field, the target material is heated and grows in the form of atoms / molecules. The grown target material atom beam (the small red dots in the above figure) diffuses toward the substrate. When the target material atoms diffuse toward the substrate, the diffusion direction is opposite to the direction of electron movement, and some atoms will be ionized by electron bombardment and become ions. The beam detection device 102 is grounded, and an ammeter is connected in series in the middle. Under the action of the electric field, some ionized ions will bombard the beam detection device 102, so that the ammeter has a current reading. Under the same conditions (same beam detection mechanism structure, material, high voltage), the magnitude of the current is proportional to the size of the growing target material atom beam. In this way, the size of the growth beam can be monitored in real time by monitoring the magnitude of the current of the beam detection device 102.

[0061] In principle, the target material grown from the same point has a large diffusion angle. In order to limit the growth angle and prevent the material from growing onto other parts in the system, a limit / guide hole is generally added to the top of the crucible to form an independent evaporation channel 1. The purpose of the independent evaporation channel 1 is to retain only the beam growing toward the substrate.

[0062] The crucible support 12 made of molybdenum rod is clamped by the stabilizing ceramic 27, which has the following functions: 1. Preventing the crucible support 12 from shaking and playing a stabilizing role; 2. Insulation; 3. When the crucible needs to move up and down, the stabilizing ceramic 27 has a certain lubricating effect. The stabilizing ceramic fixing part 28 is used to fix the stabilizing ceramic 27 on the crucible support 12 to prevent the stabilizing ceramic 27 from sliding up and down.

[0063] In the multi-channel vacuum evaporation source provided by the present invention, evaporation operations are respectively provided to the coating object through multiple groups of independent evaporation channels 1, the integrated cover 2 integrates the top ends 9 of the multiple groups of independent evaporation channels 1 in a closed space, and the multiple groups of independent evaporation channels 1 transmit the evaporated target materials to the coating object through their top ends 9. The combined baffle 3 is located between the integrated cover 2 and the coating object, and the multiple groups of independent evaporation channels 1 are connected or isolated from the coating object through opening and closing actions. The mounting flange 4 integrates the multiple groups of independent evaporation channels 1 with the baffle drive, and the baffle drive 5 controls and drives the opening and closing actions of the combined baffle 3, so that multiple different evaporation sources can provide different process conditions to the coating object according to the film material / target material, either simultaneously or in different time periods, and each independent evaporation channel 1 can be adjusted according to different materials, different process steps, and different process conditions (voltage, time or evaporation rate, etc.), so that the entire process flow is simple and easy to operate, and flexible and changeable, so that the product quality of the coating object is guaranteed.

[0064] In summary, the above embodiments describe in detail different configurations of the multi-channel vacuum evaporation source. Of course, the present invention includes but is not limited to the configurations listed in the above embodiments. Any changes based on the configurations provided in the above embodiments fall within the scope of protection of the present invention. Those skilled in the art can draw inferences based on the contents of the above embodiments.

[0065] The above description is only a description of the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Any changes or modifications made by a person skilled in the art in the field of the present invention based on the above disclosure shall fall within the scope of protection of the claims.

Claims

1. A multi-channel vacuum evaporation source, characterized in that: The multi-channel vacuum evaporation source comprises: A plurality of independent evaporation channels are configured to provide evaporation operations for the coating objects respectively; An integrated cover is configured to integrate the top ends of the plurality of independent evaporation channels in a closed space, and the plurality of independent evaporation channels respectively transmit different evaporation target materials to the coating object through the top ends thereof; A combined baffle is configured to be located between the integrated cover and the coating object, and through opening and closing actions, the plurality of independent evaporation channels are connected to or isolated from the coating object respectively; A baffle drive, configured to control and drive the opening and closing actions of the combined baffle; a mounting flange configured to integrate the plurality of independent evaporation channels with the baffle drive; The combined baffle includes a first baffle and a second baffle, and the baffle drive includes a first transmission rod and a second transmission rod, wherein: The second transmission rod is a hollow structure, and the first transmission rod is wrapped in the second transmission rod; the first transmission rod and the second transmission rod are located at the center of the integrated cover and integrated in the mounting flange; One end of the first transmission rod is connected to the first baffle, and the other end is connected to the magnetic coupling driver, so as to transmit torque between the magnetic coupling driver and the first baffle; One end of the second transmission rod is connected to the second baffle, and the other end is connected to the magnetic coupling driver, so as to transmit torque between the magnetic coupling driver and the second baffle; The integrated cover partition is placed in the cylindrical space in the middle of the integrated cover, dividing the cylindrical space into three equal parts, and a filament assembly is placed in each equal part. The partition base is supported on the base, and there are three grooves at an angle of 120° on the partition base for clamping the partition therein; The copper module and the ceramic module are used to fix the filament assembly formed by the filament and the molybdenum rod; the molybdenum rod is fixed to the ceramic module by brazing, and the ceramic module is made of ceramic to insulate the filament from the ground; The copper module is made of copper and is fixed together with the integrated cover to form a cooling closed space. The crucible and the target are located in the cooling closed space. After the crucible and the target are heated, the radiated heat is absorbed by the integrated cover, the partition, the copper module and the base to prevent heating of other components in the vacuum chamber.

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