Phase synchronization apparatus and method, and radio-frequency power supply and plasma device

Abstract

The present application belongs to the technical field of radio-frequency power supplies, and relates to a phase synchronization apparatus and method, and a radio-frequency power supply and a plasma device, which solve the phase synchronization problem between a master radio-frequency power supply and a slave radio-frequency power supply. The phase synchronization apparatus comprises a cavity signal feedback loop, which is used for establishing a feedback channel from a vacuum cavity powered by a local radio-frequency power supply to a phase shifting unit; and frequency information collected from the vacuum cavity is fed back to the phase shifting unit by means of the feedback channel to perform phase shifting processing on a local clock signal, and control information is outputted to control the phase of an output signal of the local radio-frequency power supply. The present application realizes the dynamic compensation of phase fluctuations introduced by a final-stage power amplifier, and realizes phase synchronization between a master radio-frequency power supply and a slave radio-frequency power supply.

Description

Phase synchronization device and method, radio frequency power supply and plasma equipment Technical Field

[0001] The present application belongs to the field of radio frequency power supply technology, and specifically relates to a phase synchronization device and method, a radio frequency power supply and a plasma device. Background Art

[0002] This technology is practically applied in the field of RF power supplies. It achieves output power coherence between multiple RF power supplies, synchronizing the frequency relationship between them to achieve complete coherence. In fact, the most important step in the semiconductor production process is vapor deposition. In large-scale vapor deposition, it is often not just a single power supply, but multiple power supplies that utilize the ICP effect to excite the plasma and then deposit it. In actual engineering design, it is impossible for multiple power supplies to have exactly the same frequency. Therefore, if multiple machines are directly connected to a vacuum chamber, the output frequency of each power supply is very small. Therefore, due to the superposition effect, the alternating magnetic fields between each coil will couple and superimpose each other, causing the power control loop to fail or even self-excite, which can be fatal in such a plasma environment. The solution is to use the same clock frequency for these power supplies, making them coherent.

[0003] Current technology uses local oscillator coherence within each device. The principle is to use a master and several slave devices. The master device has its own fixed clock source, and DDS technology is used to coherently synchronize its fixed clock source with a variable clock source. The slave devices' clocks are then interconnected based on the master's output clock to achieve coherence. The processor's internal phase calibration algorithm then compensates for any phase differences between each slave and the master.

[0004] A drawback of existing technology is that, according to the control loop of this AFC circuit, both the slave and the master achieve the same phase lock as the master at the small signal level of the local oscillator. However, the RF power supply actually has a high-power amplifier in the downstream stage, so the temperature phase and amplitude phase of the amplifier are open-loop. Even if the power is controlled within a certain environmental range, it can still cause unstable coupling of the coils in the vacuum chamber. Therefore, the drawback of existing technology is that the loop assumes that the group delay of the power amplifier is error-free. However, in reality, the downstream power amplifier has errors, which can lead to some unexpected control loop defects.

[0005] Summary of the Invention

[0006] In view of the above analysis, the present application aims to disclose a phase synchronization device and method, a radio frequency power supply and a plasma device to dynamically offset the phase fluctuation problem caused by the final power amplifier and solve the phase synchronization problem of the radio frequency power supply host and slave.

[0007] One aspect of the present application discloses a phase synchronization device, comprising a cavity signal feedback loop and a phase shift unit;

[0008] The cavity signal feedback loop is used to establish a feedback channel from the vacuum cavity powered by the local radio frequency power supply to the phase shift unit; the frequency information collected from the vacuum cavity is fed back to the phase shift unit through the feedback channel;

[0009] The phase shift unit is used to perform phase shift processing on the local clock signal using the frequency information collected from the vacuum cavity, and output control information to control the phase of the output signal of the local radio frequency power supply.

[0010] Another aspect of the present application further discloses a synchronization method for the phase synchronization device described above. When the phase synchronization device is located in a slave of a radio frequency power supply, the synchronization method includes the following steps:

[0011] Step S1: a phase synchronization device located in the RF power slave receives a master clock signal sent by the RF power master;

[0012] Step S2: performing an initial phase calibration of the slave clock using the input master clock as a reference, so that the slave clock frequency is based on the master clock frequency;

[0013] Step S3: The cavity signal feedback loop obtains frequency information collected from the vacuum cavity;

[0014] Step S4: Use the frequency information collected from the vacuum chamber to perform a secondary phase calibration on the slave clock that has undergone the initial phase calibration, and output corresponding control information;

[0015] After secondary phase calibration, the corresponding control information is output to control the output signal phase of the local RF power supply, ensuring the phase synchronization between the slave and the host, and offsetting the phase fluctuation caused by the local final power amplifier.

[0016] Another aspect of the present application also discloses a radio frequency power supply; comprising a power output module and a power control module;

[0017] The power control module is configured to output a driving signal to the power output module;

[0018] The power output module is used to output a radio frequency power signal for power output under the drive of the driving signal;

[0019] The power control module includes a phase synchronization device for controlling the phase of the drive signal, and the phase synchronization device is the phase synchronization device described above; when the RF power supply acts as a host, the phase synchronization device in the host is used; when the RF power supply acts as a slave, the phase synchronization device in the slave is used; to adapt to the power supply output under different power supply states.

[0020] Another aspect of the present application also discloses a radio frequency power supply for plasma equipment, comprising a radio frequency power supply master and at least one radio frequency power supply slave;

[0021] The RF power source master and the RF power source slave are connected to their respective chamber loads in the same connection manner;

[0022] The RF power master and slave use the RF power supply as described above; the RF power master maintains a standard frequency, and the frequency of the RF power slave is based on the master frequency, and they respectively power their respective chamber loads.

[0023] Another aspect of the present application further discloses a plasma device, which uses the radio frequency power supply of the plasma device described above to supply power to a chamber load of the plasma device.

[0024] This application can achieve the following beneficial effects:

[0025] The phase synchronization device disclosed in the present application realizes the frequency synchronization between the RF power supply master and the slave; and by adding a feedback loop, the phase of the synchronization signal is directly adjusted using the probe coupling output signal arranged inside the vacuum cavity, thereby achieving frequency stability inside the vacuum cavity and dynamically offsetting the phase fluctuation problem caused by the final power amplifier.

[0026] In a radio frequency power supply, a phase synchronization device is used for frequency synchronization, and a power amplifier with optimized phase response is used to improve the locking tolerance.

[0027] The RF power supply of the plasma equipment of the present application reduces the uneven power distribution caused by the superposition effect and the open-loop power amplifier phase response drift, which leads to waste wafers. Solving this problem increases the yield of semiconductor wafers. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings are only used for the purpose of illustrating specific embodiments and are not to be considered as limiting the present application. Throughout the drawings, the same reference symbols denote the same components.

[0029] FIG1 is a block diagram of the components and connections of a phase synchronization device in an embodiment of the present application;

[0030] FIG2 is a block diagram of the components and connections of a phase synchronization device in a slave of a radio frequency power supply in an embodiment of the present application;

[0031] FIG3 is a block diagram of the components and connections of a phase synchronization device in a host of a radio frequency power supply in an embodiment of the present application;

[0032] FIG4 is a flow chart of a synchronization method when the phase synchronization device is located in a slave of the RF power supply in an embodiment of the present application;

[0033] FIG5 is a block diagram of the components and connections of a radio frequency power supply in an embodiment of the present application;

[0034] FIG6 is a block diagram of the components and connections of a radio frequency power supply of a plasma device in an embodiment of the present application;

[0035] FIG7 is a schematic diagram of a master-slave connection using a daisy chain serial connection (with a matcher) in an embodiment of the present application;

[0036] FIG8 is a schematic diagram of a master-slave connection using a daisy chain serial connection in an embodiment of the present application (without a matching device);

[0037] FIG9 is a schematic diagram of a master-slave connection in which a slave is connected in parallel to a master in an embodiment of the present application (with a matching device);

[0038] FIG10 is a schematic diagram of a master-slave connection in which a slave is connected in parallel to a master in an embodiment of the present application (without a matching device);

[0039] FIG11 is a schematic diagram of a master-slave connection including a splitter (matching device is provided) in an embodiment of the present application;

[0040] FIG12 is a schematic diagram of a master-slave connection including a splitter (without a matcher) in an embodiment of the present application;

[0041] FIG13 is a diagram of a radio frequency power supply signal synchronization detection system (with a matching device) when two radio frequency power supply slaves are connected to the same vacuum chamber in an embodiment of the present application;

[0042] FIG14 is a diagram of a radio frequency power signal synchronization detection system (without a matching device) when two radio frequency power slaves are connected to the same vacuum chamber in an embodiment of the present application. DETAILED DESCRIPTION

[0043] The preferred embodiments of the present application are described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of the present application and are used together with the embodiments of the present application to illustrate the principles of the present application.

[0044] Example 1

[0045] One embodiment of the present application discloses a phase synchronization device, located in a radio frequency power supply, as shown in FIG1 , comprising a cavity signal feedback loop and a phase shift unit;

[0046] The cavity signal feedback loop is used to establish a feedback channel from the vacuum cavity powered by the local radio frequency power supply to the phase shift unit; the frequency information collected from the vacuum cavity is fed back to the phase shift unit through the feedback channel;

[0047] The phase shift unit is used to perform phase shift processing on the local clock signal using the frequency information collected from the vacuum cavity, and output control information to control the output signal phase of the local radio frequency power supply;

[0048] Phase control is used to achieve dynamic phase adjustment, phase solidification or phase difference locking of the output signal, and eliminate the phase fluctuation caused by the local final power amplifier.

[0049] During the specific implementation process, a matcher should be added between the RF power supply and the vacuum cavity according to the specific application scenario to achieve matching between the RF power supply and the vacuum cavity.

[0050] When the phase synchronization device in this embodiment is used to achieve phase synchronization between a master power supply and a slave power supply, the phase synchronization device can control the phase of the RF power signal output by the RF power master or the RF power slave. That is, the phase synchronization device can be integrated into the RF power master or the RF power slave.

[0051] When the phase synchronization device is located in the RF power slave, it can control the phase of the RF power signal output by the RF power slave according to the synchronization signal sent by the RF power master, so that it is consistent with the phase of the synchronization signal, and offset the phase fluctuation caused by the local final power amplifier according to the frequency signal collected from the vacuum cavity fed back by the feedback loop.

[0052] Specifically, the phase synchronization device is located in the slave of the RF power supply; in the phase shift unit, the initial phase calibration of the slave clock is first performed with the input master clock as a reference, so that the slave clock frequency is based on the master clock frequency; then, the frequency information collected by the vacuum cavity is used to perform a secondary phase calibration on the slave clock frequency of the initial phase calibration and then output; after the secondary phase calibration, the corresponding control information is output to control the output signal phase of the local RF power supply, thereby ensuring the phase synchronization between the slave and the master, and offsetting the phase fluctuation caused by the local final power amplifier.

[0053] More specifically, as shown in FIG2 , the phase shift unit of the phase synchronization device located in the slave of the RF power supply includes a phase shift module and a DDS module;

[0054] The first input terminal of the phase shift module is connected to the standard clock signal output by the host clock source, the second input terminal is connected to the clock signal output by the local clock source, the third input terminal is connected to the frequency information collected from the vacuum cavity, and the output terminal is connected to the DDS module;

[0055] Through the phase shift processing of the phase shift module, the slave clock is first phase-calibrated with the input master clock as a reference, so that the slave clock frequency is based on the master clock frequency; then the frequency information collected from the vacuum chamber is used to perform a secondary phase calibration on the slave clock frequency after the initial phase calibration, and the phase-shifted frequency word corresponding to the clock frequency after the phase calibration is output;

[0056] The DDS module is used to output a driving control signal with a frequency corresponding to the phase-shift frequency word under the control of the phase-shift frequency word.

[0057] The phase shift module includes a first phase shift module PH1 and a second phase shift module PH2;

[0058] The first input of the first phase shift module PH1 is connected to the standard clock signal CLKA output by the host clock source, and the second input is connected to the clock signal CLKB output by the local clock source; the output is connected to the first input of the second phase shift module PH2; the first phase shift module PH1 uses the host clock as a reference to perform initial phase calibration of the slave clock, calibrating the slave clock frequency to the host clock frequency for output;

[0059] The second input end of the second phase shift module PH2 is connected to the frequency information collected from the vacuum cavity, and the output end is connected to the frequency control word input end of the DDS module; the second phase shift module PH2 performs secondary phase calibration on the slave clock frequency calibrated by the first phase shift module PH1 according to the frequency information collected from the vacuum cavity, and outputs the phase shift frequency word corresponding to the clock frequency after phase calibration.

[0060] Specifically, the phase synchronization device is located in the main unit of the RF power supply; in the phase shifting unit, the frequency information collected from the vacuum cavity is used to calibrate the phase of the local clock source and then output, and the phase fluctuation caused by the local final power amplifier is offset by phase calibration.

[0061] In FIG2 , the first phase shift module PH1 , the second phase shift module PH2 and the DDS module are all internal modules of the FPGA (MCU) of the radio frequency power supply.

[0062] More specifically, as shown in FIG3 , the phase shift unit of the phase synchronization device located in the host of the RF power supply includes a phase shift module PH and a DDS module;

[0063] The first input terminal of the phase shift module PH is connected to the standard clock signal CLKA output by the local clock source, the second input terminal is connected to the frequency information collected from the vacuum cavity, and the output terminal is connected to the DDS module; through phase shift processing, the phase shift frequency word corresponding to the clock frequency after phase calibration is output;

[0064] The DDS module is used to output a driving control signal with a frequency corresponding to the phase-shift frequency word under the control of the phase-shift frequency word.

[0065] Preferably, the phase shift module PH can be synthesized by multiple clock phase detectors; when the host does not output power once it is turned on and there is no signal in the vacuum chamber, there is no input signal at the second input end of the phase shift module PH. The phase shift module PH generates a corresponding frequency word through the clock phase detector according to the standard clock signal CLKA at the first input end to the DDS module, thereby controlling the DDS module to output a driving control signal;

[0066] When the host's output power generates a signal within the vacuum chamber, the phase shift module (PH) performs phase shifting based on the signals input from the first and second input terminals using a clock phase detector. It then outputs a phase-shifted frequency word corresponding to the phase-calibrated clock frequency to the DDS module, which then controls the DDS module to output a drive control signal. This achieves the purpose of offsetting the phase fluctuations caused by the final power amplifier of the unit.

[0067] In FIG3 , both the phase shift module PH and the DDS module can be formed by internal modules of the FPGA (MCU) of the RF power supply.

[0068] In the cavity signal feedback loop, an analog signal including frequency and phase information of the signal inside the vacuum cavity is obtained by induction or coupling of a single electric field signal inside the vacuum cavity.

[0069] Specifically, a chamber probe (CHAMBER PROBE) may be provided at a suitable position inside the vacuum chamber to couple (induce) the signal of the single electric field inside the chamber and conduct it out.

[0070] Preferably, a chamber probe is placed inside the vacuum cavity near the location where the electric field is strongest at the excitation point in the cavity; a single electric field signal is coupled by the chamber probe to collect an analog signal including the frequency and phase information of the signal inside the vacuum cavity.

[0071] Specifically, the cavity signal feedback loop further includes an attenuator;

[0072] The attenuator is used to perform amplitude attenuation on the collected analog signal to obtain an attenuated analog signal.

[0073] The attenuated analog signal is converted by ADC and input into FPGA (MCU). The frequency information of the signal inside the vacuum cavity is calculated in MCU and fed back to the phase shift unit.

[0074] By adding a cavity signal feedback loop, a closed loop of frequency control is formed. All components in the signal chain have no open-loop components, the signal integrity is controllable, and there will be no phase fluctuations and fluctuations due to exogenous factors.

[0075] Moreover, under the closed-loop scheme through frequency control disclosed in this embodiment, the ideas inspired by using cavity sensing or adding probes inside the cavity to achieve large-loop feedback should be regarded as simple replacement schemes disclosed in this application and should not be protected by patent rights.

[0076] In summary, the phase synchronization device disclosed in the present application realizes the frequency synchronization of the RF power master and the slave; and by adding a feedback loop, the phase of the synchronization signal is directly adjusted using the probe coupling output signal arranged inside the vacuum cavity, thereby achieving frequency stability inside the vacuum cavity and dynamically offsetting the phase fluctuation problem caused by the final power amplifier.

[0077] Example 2

[0078] An embodiment of the present application discloses a synchronization method using the phase synchronization device described in Example 1, which is divided into two synchronization methods when the phase synchronization device is located in a slave and a master of a radio frequency power supply.

[0079] As shown in FIG4 , when the phase synchronization device is located in the slave of the RF power supply, the synchronization method includes the following steps:

[0080] Step S1: a phase synchronization device located in the RF power slave receives a master clock signal sent by the RF power master;

[0081] Step S2: performing initial phase calibration of the slave clock using the input master clock signal as a reference, so that the slave clock frequency is based on the master clock frequency;

[0082] Step S3: The cavity signal feedback loop obtains frequency information collected from the vacuum cavity;

[0083] Step S4: Use the frequency information collected from the vacuum chamber to perform a secondary phase calibration on the slave clock that has undergone the initial phase calibration, and output corresponding control information;

[0084] After secondary phase calibration, the corresponding control information is output to control the output signal phase of the local RF power supply, ensuring the phase synchronization between the slave and the host, and offsetting the phase fluctuation caused by the local final power amplifier.

[0085] Wherein, when the phase synchronization device is located in the host of the radio frequency power supply, the synchronization method includes the following steps:

[0086] Step S1: A phase synchronization device located in the RF power supply mainframe obtains frequency information collected from the vacuum cavity through a cavity signal feedback loop;

[0087] Step S2: using the frequency information collected from the vacuum chamber to calibrate the phase of the clock signal of the local clock source and then output it;

[0088] After phase calibration, the corresponding control information is output to control the output signal phase of the local RF power supply, offsetting the phase fluctuation caused by the local final power amplifier.

[0089] The synchronization method of this embodiment relies on the phase synchronization device described in Example 1. The specific technical details and beneficial effects are the same as those in Example 1. Please refer to the specific contents of Example 1 and will not be described in detail here.

[0090] Example 3

[0091] One embodiment of the present application discloses a radio frequency power supply, as shown in FIG5 , comprising a power output module and a power control module;

[0092] The power control module is configured to output a driving signal to the power output module;

[0093] The power output module is used to output a radio frequency power signal for power output under the drive of the driving signal;

[0094] Specifically, the power control module includes a phase synchronization device for controlling the phase of the drive signal, and the phase synchronization device is the phase synchronization device described in the first embodiment;

[0095] When the RF power supply acts as a host, a phase synchronization device in the host is used; when the RF power supply acts as a slave, a phase synchronization device in the slave is used to adapt to power supply output under different power supply states.

[0096] Specifically, the power output module includes a drive source module (POWER SUPPLY) and a final power amplifier module (DRIVE PA=>PA UNIT);

[0097] The driving source module (POWER SUPPLY) is used to output a power waveform of a specified phase and frequency under the control of the driving control signal output by the DDS module of the phase synchronization device;

[0098] The final power amplifier module (DRIVE PA=>PA UNIT) is used to amplify the power waveform of the specified phase and frequency output by the driving source module to obtain an amplified power waveform and then output it.

[0099] In order to achieve phase synchronization, the group delay of the final power amplifier and the matching device of the RF power supply should be as low as possible.

[0100] Preferably, the final power amplifier of the radio frequency power supply is a power amplifier with optimized phase response.

[0101] The specific technical details and beneficial effects of the phase synchronization device of this embodiment are the same as those in the first embodiment. Please refer to the specific contents of the first embodiment and will not be described in detail here.

[0102] Example 4

[0103] One embodiment of the present application discloses a radio frequency power supply for a plasma device, as shown in FIG6 , including a radio frequency power supply master A (MASTERA) and at least one radio frequency power supply slave B (SLAVEB);

[0104] The RF power source master and the RF power source slave are connected to their respective chamber loads in the same connection manner;

[0105] The RF power supply master and slave use the RF power supply as described in Example 3; the RF power supply master maintains a standard frequency, and the frequency of the RF power supply slave is based on the master frequency, and power is supplied to their respective chamber loads respectively; and under the control of feedback information from the cavity signal feedback loop in the power supply master and the slave, the phase fluctuation caused by the final power amplifier is dynamically offset, thereby achieving the effect of stabilizing each sub-furnace of the plasma.

[0106] In a specific master-slave connection method, a daisy-chain serial connection method is adopted; as shown in Figure 7 (with a matcher) and Figure 8 (without a matcher); the RF power supply host transmits the host clock CLKA to slave B via a serial line, and slave B forwards the host clock CLKA to slave C via another serial line, and so on, so that all slaves can receive the master clock CLKA; the length of the serial line between the master and slaves and between the slaves remains the same.

[0107] In practice, CLKA is transmitted to slave B via a line. Because line signal transmission has a delay, slave B inevitably receives a delayed CLKA-1. Slave B performs absolute phase correction on the local oscillator (LO) of CLK, adjusting the absolute phase of the received CLKA-1. After the absolute phase correction, the local oscillator (CLKB) of the slave is delayed by CLKA-1. This is due to the timing delay caused by the line transmission compared to the local oscillator (CLKA) actually used by master A.

[0108] For a daisy-chained serial connection of master and slave devices, each device is connected to a different chamber. Each device performs absolute phase correction and uses the same feedback loop architecture. Each slave device operates in a similar manner to the master. In principle, the only signal delay caused by the wiring is a fixed phase difference and fixed runtime delay between slave devices.

[0109] For example, assuming the serial cables are of equal length, the CLKA-1 received by slave B has a delay of Yus relative to the master CLKA, and a phase difference of Z. The CLKA-2 received by slave C also has a delay of Yus relative to the CLKA-1 received by slave B, and also has a phase difference of Z. After absolute phase alignment, CLKB = CLKA-1, CLKC = CLKA-2. When these signals are regulated in the same mode and enter their respective slave furnaces / chambers, there will be a delay of Yus and a phase difference of Z. However, because each slave furnace / chamber operates independently, it can form independent feedback loops to adjust its phase, ensuring stability for each slave furnace / chamber. Daisy-chain serial connections are not suitable for collaborative chambers.

[0110] In another specific master-slave connection method, the slave is connected to the master in parallel; as shown in Figure 9 (matching device is set) and Figure 10 (matching device is not set); the RF power supply host transmits the master clock CLKA to each slave in parallel through multiple connecting lines, and the length of the connecting line between the master and the slave remains the same.

[0111] In this connection mode, the number of slaves that the host can connect in parallel is determined by the driving capability of the host clock. By matching the driving capability of the host clock, it can meet the requirements of driving the set number of slaves.

[0112] In practice, CLKA is transmitted to each slave device via each parallel line. When the lines are the same length, the signal transmission delay from the master to each slave is the same, and all slave devices receive the same delayed CLKA-1. Each slave device performs absolute phase correction on the CLK local oscillator (LO) to adjust the absolute phase of the received CLKA-1. After the absolute phase correction, the local oscillator (LO) of each slave device becomes the delayed CLKA-1. In other words, each slave device and the master A's local oscillator (CLKA) actually experience the same transmission timing delay.

[0113] The slaves are connected in parallel to the master, each connected to a different chamber. Each slave performs absolute phase calibration and utilizes the same feedback loop architecture. Each slave operates in a similar mode to the master. In principle, the signal timing of each slave is synchronized only by signal delays caused by the wiring. There is a fixed phase difference and fixed operating time delay with the master.

[0114] The slaves are connected to the master in parallel. The master and slaves form independent feedback adjustment phases through their own feedback loops. After their respective sub-furnaces / chambers are stable, the absolute phase of each slave clock can be adjusted to CLKA-1 to achieve clock synchronization.

[0115] To achieve more accurate clock synchronization between slaves, a splitter is added to the aforementioned parallel connection method of the slaves to the master, as shown in Figure 11 (with a matcher) and Figure 12 (without a matcher). The input of the splitter is connected to the RF power master / host computer, receiving the master clock CLKA-1 output by the RF power master as a standard local oscillator clock signal. The N outputs of the splitter are connected to N RF power slaves via N transmission lines of equal capacity and length, providing each RF power slave with a local oscillator clock signal CLKA-2. The output of each RF power slave is connected to a corresponding vacuum chamber. The standard local oscillator clock signal passes through the splitter and the equal-length transmission lines to obtain a reference local oscillator clock signal with the same delay time and phase, ensuring that the reference local oscillator clock signals connected to the inputs of each RF power slave are coherent.

[0116] For example, this embodiment also provides a power supply method including two RF power slaves, and the output ends of the two RF power slaves are respectively connected to the upper motor and the lower motor of the same vacuum cavity. In this power supply method, according to the bias control principle of the upper motor and the lower motor of the same vacuum cavity, different phase-shifted slave local oscillator clock signals are preset for the two RF power slaves to achieve bias control of the upper motor and the lower motor of the same vacuum cavity. The RF power signal synchronization detection system when the two RF power slaves are connected to the same CCP vacuum cavity is shown in Figure 13 (matching device is set) and Figure 14 (matching device is not set). In Figures 13 and 14, one RF power slave provides RF and the other RF power slave provides bias.

[0117] Example 5

[0118] An embodiment of the present application discloses a plasma device, which uses the radio frequency power supply of the plasma device described in the fourth embodiment to supply power to a chamber load of the plasma device.

[0119] The specific technical details and beneficial effects of the radio frequency power supply of the plasma equipment are the same as those in Example 1. Please refer to the specific contents of Example 1 and will not go into details here.

[0120] The above is only a preferred specific implementation method of the present application, but the scope of protection of the present application is not limited thereto. Any changes or replacements that can be easily thought of by any technician familiar with this technical field within the technical scope disclosed in this application should be covered by the scope of protection of the present application.

Claims

1. A phase synchronization device, characterized in that: It includes a cavity signal feedback loop and a phase shift unit; The cavity signal feedback loop is used to establish a feedback channel from the vacuum cavity powered by the local radio frequency power supply to the phase shift unit; the frequency information collected from the vacuum cavity is fed back to the phase shift unit through the feedback channel; The phase shift unit is used to perform phase shift processing on the local clock signal using the frequency information collected from the vacuum cavity, and output control information to control the phase of the output signal of the local radio frequency power supply.

2. The phase synchronization device according to claim 1, characterized in that: The phase synchronization device is located in the slave of the RF power supply; in the phase shift unit, the slave clock is firstly calibrated with the input master clock as a reference, so that the slave clock frequency is based on the master clock frequency; Then, the frequency information collected by the vacuum cavity is used to perform a secondary phase calibration on the slave clock frequency that has undergone the initial phase calibration and then output; After secondary phase calibration, the corresponding control information is output to control the output signal phase of the local RF power supply, ensuring the phase synchronization between the slave and the host, and offsetting the phase fluctuation caused by the local final power amplifier.

3. The phase synchronization device according to claim 2, characterized in that: The phase shift unit includes a phase shift module and a DDS module; The first input terminal of the phase shift module is connected to the standard clock signal output by the host clock source, the second input terminal is connected to the clock signal output by the local clock source, the third input terminal is connected to the frequency information collected from the vacuum cavity, and the output terminal is connected to the DDS module; Through the phase shift processing of the phase shift module, the initial phase calibration of the slave clock is performed with the input master clock as a reference, so that the slave clock frequency is based on the master clock frequency; Then, the frequency information collected from the vacuum cavity is used to perform a secondary phase calibration on the slave clock frequency of the initial phase calibration, and the phase-shifted frequency word corresponding to the clock frequency after the phase calibration is output; The DDS module is used to output a driving control signal with a frequency corresponding to the phase-shift frequency word under the control of the phase-shift frequency word.

4. The phase synchronization device according to claim 3, characterized in that: The phase shift module includes a first phase shift module PH1 and a second phase shift module PH2; The first input terminal of the first phase shift module PH1 is connected to the standard clock signal output by the host clock source, and the second input terminal is connected to the clock signal output by the local clock source; The output end is connected to the first input end of the second phase shift module PH2; The first phase shift module PH1 uses the master clock as a reference to perform initial phase calibration of the slave clock, calibrating the slave clock frequency to the master clock frequency for output; The second input end of the second phase shift module PH2 is connected to the frequency information collected from the vacuum cavity, and the output end is connected to the frequency control word input end of the DDS module; the second phase shift module PH2 performs secondary phase calibration on the slave clock frequency calibrated by the first phase shift module PH1 according to the frequency information collected from the vacuum cavity, and outputs the phase shift frequency word corresponding to the clock frequency after phase calibration.

5. The phase synchronization device according to claim 1, wherein: The phase synchronization device is located in the main unit of the radio frequency power supply; in the phase shifting unit, the frequency information collected from the vacuum cavity is used to calibrate the phase of the local clock source and then output it, and the phase fluctuation caused by the local final power amplifier is offset by phase calibration.

6. The phase synchronization device according to claim 5, characterized in that: The phase synchronization device located in the main unit of the radio frequency power supply includes a phase shift module and a DDS module; The first input end of the phase shift module is connected to the standard clock signal output by the local clock source, the second input end is connected to the frequency information collected from the vacuum cavity, and the output end is connected to the DDS module; Through phase shift processing, the phase-shifted frequency word corresponding to the clock frequency after phase calibration is output; The DDS module is used to output a driving control signal with a frequency corresponding to the phase-shift frequency word under the control of the phase-shift frequency word.

7. The phase synchronization device according to claim 1-6, characterized in that: In the cavity signal feedback loop, an analog signal including frequency and phase information of the signal inside the vacuum cavity is obtained by induction or coupling of a single electric field signal inside the vacuum cavity.

8. The phase synchronization device according to claim 7, characterized in that: Place the chamber probe in the vacuum chamber near the location where the electric field is strongest at the excitation point in the chamber. The chamber probe couples a single electric field signal and collects an analog signal including the frequency and phase information of the signal inside the vacuum cavity.

9. The phase synchronization device according to claim 7, characterized in that: The cavity signal feedback loop also includes an attenuator; The attenuator is used to perform amplitude attenuation on the collected analog signal to obtain an attenuated analog signal.

10. A synchronization method for the phase synchronization device according to any one of claims 1 to 9, characterized in that: include: When the phase synchronization device is located in a slave of the radio frequency power supply, the synchronization method includes the following steps: Step S1: a phase synchronization device located in the RF power slave receives a master clock signal sent by the RF power master; Step S2: performing an initial phase calibration of the slave clock using the input master clock as a reference, so that the slave clock frequency is based on the master clock frequency; Step S3: The cavity signal feedback loop obtains frequency information collected from the vacuum cavity; Step S4: Use the frequency information collected from the vacuum chamber to perform a secondary phase calibration on the slave clock that has undergone the initial phase calibration, and output corresponding control information; After secondary phase calibration, the corresponding control information is output to control the output signal phase of the local RF power supply, ensuring the phase synchronization between the slave and the host, and offsetting the phase fluctuation caused by the local final power amplifier.

11. The synchronization method of the phase synchronization device according to claim 10, characterized in that: When the phase synchronization device is located in the host of the radio frequency power supply, the synchronization method includes the following steps: Step S1: A phase synchronization device located in the RF power supply mainframe obtains frequency information collected from the vacuum cavity through a cavity signal feedback loop; Step S2: using the frequency information collected from the vacuum chamber to calibrate the phase of the clock signal of the local clock source and then output it; After phase calibration, the corresponding control information is output to control the output signal phase of the local RF power supply, offsetting the phase fluctuation caused by the local final power amplifier.

12. A radio frequency power supply, characterized in that: Including power output module and power control module; The power control module is configured to output a driving signal to the power output module; The power output module is used to output a radio frequency power signal for power output under the drive of the driving signal; The power control module includes a phase synchronization device for controlling the phase of the drive signal, and the phase synchronization device is the phase synchronization device according to any one of claims 1 to 9; when the RF power supply acts as a host, the phase synchronization device in the host is adopted; when the RF power supply acts as a slave, the phase synchronization device in the slave is adopted; to adapt to the power supply output under different power supply states.

13. The radio frequency power supply according to claim 12, characterized in that: The final stage power amplifier included in the power output module is a power amplifier with optimized phase response.

14. A radio frequency power supply for plasma equipment, characterized in that: It includes a radio frequency power supply master and at least one radio frequency power supply slave; The RF power source master and the RF power source slave are connected to their respective chamber loads in the same connection manner; The RF power supply master and slave use the RF power supply as claimed in claim 12 or 13; the RF power supply master maintains a standard frequency, and the frequency of the RF power supply slave is based on the master frequency, and supplies power to their respective chamber loads.

15. A plasma device, characterized in that: The plasma equipment uses the radio frequency power supply of the plasma equipment as claimed in claim 14 to supply power to the chamber load of the plasma equipment.

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