Multi-port Phase Compensation Nested Microwave Plasma Diamond Film Deposition Device

Abstract

The invention discloses a multi-port phase-compensated nested microwave plasma diamond film deposition device, wherein a resonant cavity part comprises an inner cavity, an annular waveguide, a slit opening, a quartz ring, a metal stage, a deposition stage, a substrate and a groove, wherein the slit opening is located on the wall of the inner cavity and connects the inner cavity with the annular waveguide; the metal stage supports the quartz ring; the deposition stage is arranged at the bottom center of the inner cavity and is in an I-shape; the substrate is arranged above the deposition stage; the groove is arranged at the top of the inner cavity; the inner cavity and the quartz ring are both hollow cylindrical, and the annular waveguide is arranged around the inner cavity; a plurality of microwave transmission parts are arranged, all of which are connected to the resonant cavity part to feed microwaves into the inner cavity, and comprise a microwave source, a circulator and a waveguide magic-T structure, wherein the microwave source generates microwave oscillations, the circulator is arranged at the outlet of the microwave source to protect the microwave source from being affected by the reflected microwave power, and the waveguide magic-T structure is used for tuning impedance.

Description

Technical Field

[0001] The present invention belongs to the technical field of diamond film deposition, and relates to a multi-port phase compensation nested microwave plasma diamond film deposition device. Background Art

[0002] As a low-temperature plasma technology, microwave plasma can well avoid the pollution of electrodes and the vessel wall due to its characteristics of electrodeless discharge and concentrated discharge area. At the same time, its high ionization degree and strong reaction activity result in a large plasma energy density and a high electron temperature, enabling the acquisition of a high concentration of atomic hydrogen, and the discharge process is also very stable. Therefore, microwave plasma is a method for depositing high-quality diamond films.

[0003] Typical microwave plasmas include electron cyclotron resonance microwave plasma, surface wave plasma, and resonant cavity microwave plasma. Among them, electron cyclotron resonance microwave plasma utilizes an externally applied magnetic field to excite the resonance phenomenon between electrons and the microwave frequency, which can greatly increase the plasma density. However, due to operating under low-pressure conditions, the deposition rate is very low, and the quality of the diamond film is also affected. The typical characteristic of surface wave plasma is that microwaves can only excite the plasma during the process of propagating along the plasma surface and cannot enter the interior of the plasma region. Different from the above two, the generation of resonant cavity microwave plasma relies on the high-strength variable electric field formed by microwaves in the resonant cavity to directly excite the gas to generate plasma. It has a high plasma energy density and a high concentration of active groups, and is more suitable for depositing thin film materials.

[0004] In China, the 2.45 GHz microwave plasma CVD diamond film deposition device has gone through a change process from quartz tube type, quartz bell jar type, cylindrical resonant cavity type, loop antenna type, ellipsoidal resonant cavity type, and various other types of MPCVD devices. The problems existing in its development process can be summarized as a large amount of microwave energy being absorbed, the dielectric window being easily etched, weak tunability, small deposition size, and unsatisfactory deposition rate, etc.

[0005] Currently, domestic teams have conducted relatively in-depth and systematic research on various resonant cavity structures of MPCVD. For example, the team led by Tang Weizhong from the Functional Research Institute of the University of Science and Technology Beijing is at the leading level in China in the development of CAP type cylindrical resonant cavity and ellipsoidal resonant cavity MPCVD equipment; the first MPCVD equipment independently developed by the team led by Hao Yue from the Wuhu Research Institute of Xidian University can achieve the growth of polycrystalline diamond heat dissipation substrates with a size of 2 - 3 inches; the team led by Wang Jianhua from the Hubei Key Laboratory of Plasma Chemistry and New Materials at Wuhan Institute of Technology has also made substantial progress in the development of 1 - 75 kW full series of MPCVD equipment. However, compared with foreign research teams, domestic microwave plasma resonant cavities still need to break through in key technologies such as independent optimization design and large size.

[0006] In 1994, the University of Wuppertal in Germany developed a slit antenna type plasma source (SLAN). Its characteristic is that the area of the generated plasma is not restricted by the microwave wavelength, and the diameter can vary from 4 cm to 67 cm. Correspondingly, the gas pressure range required to maintain plasma uniformity is also different. For the SLAN source with a 4-cm diameter, the operating gas pressure is as high as the atmospheric pressure, which is equivalent to a plasma jet type MPCVD device; while for the SLAN with a 67-cm diameter, it is equivalent to a plasma source operating at low pressure.

[0007] In 1997, the Institute of Plasma Physics of the Chinese Academy of Sciences measured the electric field distribution in the annular waveguide slot antenna without plasma under low-power conditions using the microwave single probe method, and measured the characteristics of the argon plasma of this source using the Langmuir double probe. It is reported that optimization work such as increasing the microwave power and reducing the gas pressure will be carried out in the future.

[0008] The existing devices for generating large-size microwave plasmas mainly utilize the diffraction effect of the microwave by the slit antenna, making slit openings on the waveguide wall to form a waveguide slot antenna. However, since the strong field region is mainly concentrated at the slit opening, it will cause the problem of secondary plasma etching the dielectric window when the power is too high. In recent years, the waveguide slot array antenna has been widely used due to a series of outstanding advantages such as low loss, high radiation efficiency, and stable performance, which also provides a possibility for the improvement of the microwave plasma diamond film deposition device.

[0009] There are mainly two technical solutions in the prior art. The first technology focuses on the improvement of the electric field by the cooperation of the narrow slit and the large slit in order to obtain a more uniform plasma, and it only involves the structural design of the resonant cavity. In the actual application process, the microwave plasma deposition device also needs to include, but is not limited to, impedance tuning structures, microwave sources, circulators, cooling and gas inlet and outlet systems, etc. All these need to match the relevant indicators and relevant equipment according to simulation analysis and performance requirements. A single resonant cavity does not have universality. Moreover, multi-port phase control is not adopted. In the second technology, the way of feeding microwaves into the resonant cavity from the side increases the microwave transmission distance, resulting in a large amount of energy attenuation, which is not conducive to improving the coupling efficiency and also affects the simplification of the device structure. At the same time, when microwaves are coupled into the plasma chamber through the slit, multiple strong field convergence regions must be formed. However, in the actual application process, a stable and concentrated single strong field region is required to excite gas to form plasma for diamond film deposition, that is, the interior of the deposition device is lacking in perfection. Secondly, the three-pin tuner and short-circuit piston structure can only be limited to the tuning of the TE mode and cannot tune the TM mode, that is, there is no effective tuning effect on the magnetic field. The matching blind area of the pin-top structure in the admittance original diagram indicates that the tuning ability of the device itself is limited. Finally, when the multi-ring waveguide resonator is coupled in the same direction with the plasma chamber, although a large-size plasma can be formed, the device structure is complex and the cost is too high. Summary of the Invention

[0010] To solve at least the following defects in the prior art: it is easy to accumulate carbon on the top cover baffle part during application, which is not conducive to the growth of diamond; the plasma density is relatively low, and the area of the deposited diamond film is small; the cooling efficiency of the device is relatively low, which is not conducive to increasing the microwave input power. The purpose of the present invention is to provide a multi-port phase compensation nested microwave plasma diamond film deposition device, and the technical solution is as follows:

[0011] A multi-port phase compensation nested microwave plasma diamond film deposition device includes a resonant cavity part and a microwave transmission part, wherein,

[0012] The resonant cavity part includes an inner cavity body, a ring waveguide, a slit opening, a quartz ring, a metal table, a deposition table, a substrate and a groove. Among them, the slit opening is located on the wall of the inner cavity body and communicates the inner cavity body with the ring waveguide; the metal table is arranged around the bottom of the inner cavity body, and the metal table supports the quartz ring; the deposition table is arranged at the center position of the bottom of the inner cavity body and is in an I shape; the substrate is arranged above the deposition table and is in a disc shape; the groove is arranged at the top of the inner cavity body and is in a cylindrical shape; both the inner cavity body and the quartz ring are hollow cylindrical, the ring waveguide surrounds the inner cavity body and is in a circular ring shape, and the cross-section is rectangular;

[0013] A plurality of the microwave transmission parts are provided and are all connected to the resonant cavity part to feed microwaves into the inner cavity body. The microwave transmission part includes a microwave source, a circulator and a waveguide magic-T structure. The microwave source generates microwave oscillations. The circulator is arranged at the outlet of the microwave source to protect the microwave source from the influence of the reflected microwave power. The waveguide magic-T structure is used for impedance tuning.

[0014] Preferably, the microwave source includes a fully shielded magnetron or a microwave transistor.

[0015] Preferably, a flange cover is further included, which is arranged at the top and bottom of the inner cavity body and is detachably assembled with the inner cavity body.

[0016] Preferably, an air inlet and an air outlet are further included. The air inlet is located at the bottom of the cylindrical groove at the top of the inner cavity body and jets gas vertically downward to the I-shaped deposition table. The air outlet is located at the bottom of the inner cavity body on both sides of the I-shaped deposition table.

[0017] Preferably, an observation round hole is further included, which is arranged around the outer wall of the inner cavity body.

[0018] Preferably, an infrared thermometer is further included, which is arranged on the outer wall of the upper half of the inner cavity body and points to the center of the spherical plasma formed in the inner cavity body during resonance.

[0019] Preferably, an air cooling device is further included, which is arranged below the inner cavity body for heat dissipation of the quartz ring.

[0020] Preferably, a water cooling device is further included, which is arranged on the flange cover, the deposition table, the magnetron and the circulator part.

[0021] Preferably, the depth of the groove and the height of the deposition table are adjustable.

[0022] Preferably, an excitation method of controlling multiple ports to input with different microwave powers according to a preset phase is adopted.

[0023] Compared with the prior art, the present invention has at least the following beneficial effects:

[0024] 1. A microwave plasma device coupled by a multi-port phase modulation slot antenna is proposed. Specifically, a feeding method of controlling multiple ports to input with different microwave powers according to a certain phase is adopted to enhance the electric field intensity coupled into the plasma chamber, thereby improving the excitation degree of the gas and generating a higher-density and more concentrated plasma;

[0025] 2. The design device cancels the three-pin tuner, the short-circuit piston and the mode converter, simplifying the structure of the microwave plasma deposition device;

[0026] 3. By adopting the method of directly feeding the TE mode microwave, the attenuation of the microwave energy caused by side feeding is avoided, and the coupling efficiency is improved;

[0027] 4. The impedance tuning structure uses multiple sets of waveguide magic-T structures to couple electromagnetic coupling, cancels the design of the three-pin tuner and the short-circuit piston, so that there is no blind area in impedance matching and it is easy to tune.

[0028] 5. The internal structure of the resonant cavity part is designed to form a unique strong-field region in the plasma chamber, so that the volume of the deposited plasma increases and becomes more stable, which can be used for the preparation of large-size diamond films.

[0029] 6. It overcomes the problem of low microwave power of traditional slit antennas. The quartz medium is close to the deposition table, and a maximum electric field region is accurately cut in the plasma chamber, which can avoid the inner wall of the quartz ring being etched by secondary plasma. This device can achieve efficient deposition of large-area high-quality diamond films under high microwave input power conditions (10 kw). Brief Description of the Drawings

[0030] Figure 1 It is a schematic structural diagram of the multi-port phase compensation nested microwave plasma diamond film deposition device according to the embodiment of the present invention;

[0031] Figure 2 It is a schematic diagram of the resonant cavity part of the multi-port phase compensation nested microwave plasma diamond film deposition device according to the embodiment of the present invention;

[0032] Figure 3 It is a schematic diagram of the enlarged bottom structure of the quartz ring of the multi-port phase compensation nested microwave plasma diamond film deposition device according to the embodiment of the present invention;

[0033] Figure 4 It is a schematic structural diagram of the microwave transmission part of the multi-port phase compensation nested microwave plasma diamond film deposition device according to the embodiment of the present invention;

[0034] Figure 5 It is a schematic diagram of the external structure of the resonant cavity of the multi-port phase compensation nested microwave plasma diamond film deposition device according to the embodiment of the present invention;

[0035] Figure 6 It is the electric field distribution diagram of the resonant cavity part in the prior art;

[0036] Figure 7 It is the initial electric field distribution diagram of the slot coupling of the resonant cavity part of the multi-port phase compensation nested microwave plasma diamond film deposition device according to the embodiment of the present invention;

[0037] Figure 8 It is the ne image distribution diagram of the resonant cavity part of the multi-port phase compensation nested microwave plasma diamond film deposition device according to the embodiment of the present invention;

[0038] Figure 9This is the partial electric field distribution diagram of the five-port resonator of the multi-port phase compensation nested microwave plasma diamond film deposition device according to the embodiment of the present invention. Detailed implementation manners

[0039] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0040] On the contrary, the present invention covers any alternatives, modifications, equivalent methods and solutions made within the spirit and scope of the present invention defined by the claims. Further, in order to enable the public to better understand the present invention, some specific details are described in detail in the following detailed description of the present invention. Those skilled in the art can fully understand the present invention without the description of these details.

[0041] Refer to Figures 1-3 , which shows the multi-port phase compensation nested microwave plasma diamond film deposition device according to the embodiment of the present invention, including a resonator part 20 and a microwave transmission part 30. Among them,

[0042] The resonator part 20 includes an inner cavity body 1, an annular waveguide 2, a slot opening 3, a quartz ring 4, a metal platform 5, a deposition platform 6, a substrate 7 and a groove 8. Among them, the slot opening 3 is located on the wall of the inner cavity body 1 and communicates the inner cavity body 1 with the annular waveguide 2; the metal platform 5 is arranged around the bottom of the inner cavity body 1, and the metal platform 5 supports the quartz ring 4; the deposition platform 6 is arranged at the center position of the bottom of the inner cavity body 1 and is in an I shape; the substrate 7 is arranged above the deposition platform 6 and is in a disc shape; the groove 8 is arranged at the top of the inner cavity body 1 and is in a cylindrical shape; both the inner cavity body 1 and the quartz ring 4 are hollow cylinders, the annular waveguide 2 surrounds the inner cavity body 1 and is in a circular ring shape, and the cross section is a rectangle;

[0043] A plurality of microwave transmission parts 30 are provided and are all connected to the resonator part 20 to feed microwaves into the inner cavity body 1. The microwave transmission part 30 includes a microwave source 9, a circulator 10 and a waveguide magic-T structure 11. The microwave source 9 generates microwave oscillations. The circulator 10 is arranged at the outlet of the microwave source 9 to protect the microwave source 9 from the influence of the reflected microwave power. The waveguide magic-T structure 11 is used to tune the impedance. The microwave source 9 includes a fully shielded magnetron or a microwave transistor.

[0044] The design of the above device is as follows. First, using electromagnetic simulation software, analyze the field distribution of microwaves with a frequency of 2.45 GHz in a standard WR340 rectangular waveguide. It is noted that there are vertically downward and vertically upward surface currents alternating on the sidewalls of the rectangular waveguide. Considering making a transverse groove on the waveguide sidewall to vertically cut the surface current, the microwave energy in the waveguide can be radiated from the side, which is equivalent to a slot antenna. Then, consider winding the straight rectangular waveguide into a ring so that the side of the waveguide forms a cylindrical side to converge the microwave energy, and the initial waveguide partial structure can be obtained. Second, according to the relevant theoretical knowledge of waveguide transmission, optimize this partial structure until a strong field region with uniform distribution is formed in the annular waveguide 2. It is noted that at this time, the magnetic field directions in each strong field region are clockwise and counterclockwise alternately. To couple microwaves from the inner sidewall of the annular waveguide 2 into the inner cavity, it is necessary to select the region in the annular waveguide 2 where the magnetic field is in the same direction as the magnetic field of the inner cavity to be excited for the slot opening 3 treatment. The size of the slot opening 3 needs to be optimized by combining the electromagnetic field numerical analysis method and analyzing various parameters of the slot antenna with the help of high-frequency electromagnetic analysis software. The shape of the inner cavity body 1 can be the simplest cylinder, and the specific size can be determined by the method of characteristic frequency. Finally, improve the internal structure to obtain the complete resonant cavity part 20, and then add the microwave transmission part 30.

[0045] The present invention adopts an excitation method of controlling multiple ports to input different microwave powers according to a preset phase, which is used to enhance the electric field strength coupled into the inner cavity body 1 and improve the coupling efficiency.

[0046] Adopt the method of directly feeding the microwave transmission part 30 into the resonant cavity part 20 to avoid the attenuation of microwave energy caused by side feeding.

[0047] Adopt multiple waveguide magic-T structures 11 to replace the design of three-pin tuners and short-circuit pistons, so that there is no blind area in impedance matching and it is easy to tune;

[0048] The quartz ring 4 is close to the deposition table 6 to accurately cut a maximum electric field region in the plasma chamber, avoiding the inner wall of the quartz ring 4 from being etched by secondary plasma.

[0049] In a specific embodiment, refer to Figure 5, the metal bellows 13 is located above the resonant cavity part 20 and is used to control the lifting of the depth of the cylindrical groove 8 at the top of the inner cavity body 1. The bottom I-shaped deposition table 6 also has a structure that can be adjusted up and down, and both can be used to adjust the electric field distribution in the inner cavity body 1 during resonance to obtain a better plasma state, and the tunability of the overall device is better. The flange covers 14 are located at the top and bottom of the resonant cavity part 20 and are detachable to ensure the airtightness of the overall device. The gas inlet is located at the bottom of the cylindrical groove 8 at the top of the inner cavity body 1 and jets gas vertically downward to the I-shaped deposition table 6, which is beneficial to the concentrated excitation of the plasma on the deposition table 6; the gas outlet is located at the bottom of the inner cavity body 1 on both sides of the I-shaped deposition table 6. The infrared thermometer 15 is located on the outer wall of the upper half of the resonant cavity part 20 and points to the center of the spherical plasma formed in the inner cavity body 1 during resonance. The observation round holes 16 are distributed below the infrared thermometer 15 and surround the outer wall of the upper half of the resonant cavity part 20, Figure 5 One week is not shown in the figure, and only a part is shown for example. There is a mesh structure at the connection between the observation round hole 16 and the outer wall of the inner cavity body 1, which hinders the microwave from radiating outside the resonant cavity part 20 through the observation round hole 16. The excitation of the plasma can be directly observed through the observation round hole 16. The grid diameter is generally less than one-eighth of the microwave wavelength, and the actual setting can be 6 mm. The sealing of the resonant cavity part 20 is mainly in the quartz ring 4 structure surrounding the plasma reaction chamber, and the observation round hole 16 structure only needs to ensure the airtightness of the overall device. For the specific method of ensuring airtightness of the quartz ring 4, please refer to Figure 3 A table groove 51 is made above the metal table 5, the bottom of the quartz ring 4 is embedded in the table groove 51, and the bottom of the table groove 51 is embedded with a rubber ring 41. The top of the quartz ring 4 is in contact with the top of the inner cavity body 1. The bottom of the quartz ring 4 squeezes the rubber ring 41 to ensure the overall airtightness of the structure of the quartz ring 4 part. In the electromagnetic simulation software, the position of the quartz ring 4 can be parametrically set to observe the change of the electric field distribution in the resonant cavity part 20, and the position of the quartz ring 4 with concentrated electric field distribution and a larger field area is selected as the optimal solution.

[0050] The cooling system mainly includes two parts. An air-cooling device is used close to the lower part of the resonant cavity part 20 for the heat dissipation of the quartz ring 4. The water-cooling device indirectly contacts the flange covers 14 at the top and bottom of the resonant cavity part 20, the I-shaped deposition table 6 in the inner cavity body 1, the magnetron and the circulator 10, etc. through the inlet and outlet water pipes. The water flow is adjusted by the water distributor to match the cooling requirements of each part to ensure the stable operation of the entire device under high microwave power input.

[0051] The microwave source 9 includes a fully shielded magnetron for generating microwaves of the required power; a circulator 10 is provided at its outlet to protect the magnetron from the influence of reflected microwave power; the microwave source 9 can generate microwave oscillations by different electronic devices, including magnetrons, microwave transistors, etc. The tuning section adopts a waveguide magic-T structure 11, which consists of an E-T stub and an H-T stub, and can adjust the microwave input impedance of the plasma source and reduce the reflection coefficient.

[0052] The microwaves are directly fed into the resonant cavity section 20 via the waveguide magic-T structure 11 to form ten uniformly distributed strong field regions in the annular waveguide 2. Among them, the number of strong field regions in the annular waveguide 2 is adjustable, the difference between the inner and outer diameters of the annular waveguide 2 is constant, approximately equal to the waveguide wavelength, but the length of the inner diameter can be adjusted within a certain range according to the size of the plasma chamber to be deposited in the inner cavity 1. Note that if the inner diameter is too large, it will affect the convergence of microwave energy; if it is too small, the size of the deposited diamond film will be too small, and the research of the device itself will be meaningless. In a specific embodiment, ten are selected. Select the strong field regions in the annular waveguide 2 where the magnetic field direction is consistent with the rotation direction of the magnetic field in the inner cavity to be excited, and make annular slot openings 3, the length of which is approximately equal to the inner ring curve length of the selected region. The microwaves are coupled into the inner cavity 1 from the slot openings 3 to form multiple strong field regions, and the electric field distribution is as Figure 6 shown. At this time, a microwave transmission section 30 is adopted. When adding a multi-port input structure later, another microwave transmission section 30 can be added, and a power divider is used to distribute the microwave energy of each port.

[0053] After the microwaves are successfully fed in, a cylindrical deposition table 6 is added in the inner cavity 1 for depositing plasma at the exact center of the inner cavity 1. The substrate is located above the deposition table 6 and is slightly smaller in size. A quartz ring 4 is constructed near the slot openings 3. The bottom of the quartz ring 4 is fixed above the metal table 5 with a slightly wider width by embedding an O-ring 41 through grooving. A cylindrical grooving treatment is performed on the top of the inner cavity 1 to compress the plasma so that it clings to the upper part of the deposition table 6. In order to increase the further tuning effect, the deposition table 6 can also be processed into an I-shaped shape to reduce the electric field distribution. The electric field distribution and the ne image of the improved resonant cavity section 20 structure are respectively as Figure 7 、 Figure 8 shown. The shown device structure only includes one microwave transmission section 30, that is, one microwave source 9 is adopted.

[0054] Multi-port input structure: Through certain phase control, ports with different microwave input powers are added to improve the traditional single microwave port input mode to a multi-port microwave input mode, so as to strengthen the electric field intensity coupled into the inner cavity 1, and then enhance the excitation degree of the gas, thereby obtaining a higher density of plasma. Figure 1 、 Figure 9They are respectively the simplest five-port structure with an input power of the same and a phase difference of 72 degrees, and the corresponding electric field pattern. It can be seen that the maximum value of the electric field intensity coupled into the inner cavity 1 has increased by nearly twice. Of course, there are also many other optimized structures. The key lies in controlling multiple ports according to a certain phase to input different microwave powers and the feeding structure with phase control to enhance the coupling effect of the electric field in the inner cavity 1. See Figure 9 , except for the microwave source 9, the structures of the five microwave transmission parts 30 are the same. The microwave power input at each port can be distributed by a power divider, and two microwave sources 9 can be added.

[0055] Device operation mode

[0056] 1. Open the air inlet and outlet of the resonant cavity part 20, spontaneously feed in external air to balance the air pressure inside and outside the inner cavity 1, start the stepper motor to lower the deposition table 6, select a silicon wafer with an appropriate size and place it above the deposition table 6 as the substrate 7, and then raise the deposition table 6 again to close it at the bottom of the inner cavity 1;

[0057] 2. Use a vacuum pump to evacuate the low-pressure area surrounded by the quartz ring 4 inside the inner cavity 1. The range of the low-pressure area is the area surrounded by the quartz ring 4 in the inner cavity 1. This area will be evacuated to a vacuum before microwave operation, and gas is introduced to adjust the internal air pressure, so it is called the low-pressure area; at the same time, observe the readings of the pressure gauges of the large and small ranges. After meeting the requirements, introduce the reaction gas and adjust the gas pressure in the device;

[0058] 3. Turn on the water cooling and air cooling related equipment, check whether parameters such as the flow rate meet the requirements through the flow sensor, and at the same time conduct a comprehensive inspection of the entire device;

[0059] 4. Input microwaves with a frequency of 2.45 GHz and a power of 10000 W, and observe the generation of plasma through the observation hole 16; adjust the position of the short-circuit piston of the waveguide magic-T structure 11 and the lifting height of the metal bellows 13 to reduce the reflection coefficient of the device, and then start the deposition of diamond film;

[0060] 5. After depositing for a period of time, sequentially turn off structures such as the gas, microwave power supply, and vacuum pump to end the deposition of the diamond film.

[0061] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A multi-port phase compensation nested microwave plasma diamond film deposition device, characterized in that, It includes a resonant cavity part and a microwave transmission part. Among them, the resonant cavity part includes an inner cavity body, a ring waveguide, a slot opening, a quartz ring, a metal table, a deposition table, a substrate and a groove. Among them, the slot opening is located on the wall of the inner cavity body, connecting the inner cavity body and the ring waveguide; the metal table is arranged around the bottom of the inner cavity body to support the quartz ring; the deposition table is arranged at the center of the bottom of the inner cavity body and is in the shape of a capital "I"; the substrate is arranged above the deposition table and is disc-shaped; the groove is arranged at the top of the inner cavity body and is cylindrical; both the inner cavity body and the quartz ring are hollow cylinders, the ring waveguide surrounds the inner cavity body and is circular, and its cross-section is rectangular. A number of microwave transmission parts are provided and are all connected to the resonant cavity part to feed microwaves into the inner cavity body. The microwave transmission part includes a microwave source, a circulator and a waveguide magic-T structure. The microwave source generates microwave oscillations. The circulator is arranged at the outlet of the microwave source to protect the microwave source from the influence of the reflected microwave power. The waveguide magic-T structure is used to tune the impedance. The microwave source includes a fully shielded magnetron or a microwave transistor. It also includes flange covers, which are arranged at the top and bottom of the inner cavity body and are detachably assembled with the inner cavity body. It also includes an air inlet and an air outlet. The air inlet is located at the bottom of the cylindrical groove at the top of the inner cavity body and jets gas vertically downward to the capital "I"-shaped deposition table; the air outlet is located at the bottom of the inner cavity body on both sides of the capital "I"-shaped deposition table. The depth of the groove and the height of the deposition table are adjustable. An excitation method is adopted to control multiple ports according to a preset phase to input different microwave powers.

2. The multi-port phase compensation nested microwave plasma diamond film deposition device according to claim 1, wherein, It also includes observation round holes, which are arranged around the outer wall of the inner cavity body.

3. The multi-port phase compensation nested microwave plasma diamond film deposition device according to claim 1, wherein, It also includes an infrared thermometer, which is arranged on the outer wall of the upper half of the inner cavity body and points to the center of the spherical plasma formed in the inner cavity body during resonance.

4. The multi-port phase compensation nested microwave plasma diamond film deposition device according to claim 1, wherein It also includes an air cooling device, which is arranged below the inner cavity body for heat dissipation of the quartz ring.

5. The multi-port phase compensation nested microwave plasma diamond film deposition device according to claim 1, wherein, It also includes a water cooling device, which is arranged on the flange cover, the deposition table, the magnetron and the circulator part.

Images