Radio frequency power supply and semiconductor process equipment

Abstract

The embodiment of the invention provides a radio frequency power supply and semiconductor process equipment, and the power supply comprises a power supply voltage control sub-module which is connected with a switching power supply module and is used for controlling the DC output voltage of the switching power supply module; the radio frequency control sub-module is connected with the radio frequency module and is used for controlling the power and the frequency of the radio frequency signal output by the radio frequency module; the power sampling sub-module is used for being connected with the radio frequency module and collecting a power feedback value of a radio frequency signal output by the radio frequency module; and the processor sub-module is connected with the power supply voltage control sub-module, the radio frequency control sub-module and the power sampling sub-module, and is used for outputting a control signal to the power supply voltage control sub-module and the radio frequency control sub-module based on the power feedback value and the frequency of the radio frequency signal, so that the radio frequency module outputs the required radio frequency signal. The embodiment of the invention can improve the output efficiency of the radio frequency module.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and particularly to a radio frequency power supply and a semiconductor processing apparatus. Background Art

[0002] A radio frequency power supply is an energy conversion device that converts industrial frequency AC input power into radio frequency power. Its hardware mainly consists of three parts: a radio frequency module, a control module, and a switching power supply module. Among them, the radio frequency module processes a 13.56 MHz drive signal through filtering, amplification, power synthesis, etc. and then outputs it. The control module is responsible for radio frequency power closed-loop control, radio frequency drive signal control, and switching power supply voltage control. The switching power supply module is responsible for converting industrial frequency AC input power into DC power required by the radio frequency module and the control module.

[0003] The control module of the traditional radio frequency power supply adopts an analog control scheme. However, this type of radio frequency power supply has the disadvantages of slow response, and cannot implement the pulse output function of radio frequency power. And it cannot set the frequency to achieve the function of fast frequency sweeping. Summary of the Invention

[0004] In view of the above problems, embodiments of the present invention are proposed to provide a radio frequency power supply and a semiconductor processing apparatus that overcome the above problems or at least partially solve the above problems.

[0005] To solve the above problems, in the first aspect of the present invention, embodiments of the present invention disclose a radio frequency power supply, including: a control module, a switching power supply module, and a radio frequency module. The switching power supply module is used to provide a DC output voltage to the radio frequency module, and the radio frequency module is used to output a required radio frequency signal; the control module includes:

[0006] A power supply voltage control sub-module, connected to the switching power supply module, for controlling the DC output voltage of the switching power supply module;

[0007] A radio frequency control sub-module, connected to the radio frequency module, for controlling the power and frequency of the radio frequency signal output by the radio frequency module;

[0008] A power sampling sub-module, for being connected to the radio frequency module, for collecting a power feedback value of the radio frequency signal output by the radio frequency module;

[0009] A processor sub-module, connected to the power supply voltage control sub-module, the radio frequency control sub-module, and the power sampling sub-module, for outputting control signals to the power supply voltage control sub-module and the radio frequency control sub-module based on the power feedback value and the frequency of the radio frequency signal, so that the radio frequency module outputs a required radio frequency signal.

[0010] Optionally, the RF module includes: an RF circuit, an acquisition circuit, and an RF output circuit connected in sequence;

[0011] The RF circuit is connected to the switching power supply module and the RF control sub-module;

[0012] The sampling circuit is used to collect the feedback values of the forward power and the reflected power output by the RF circuit, and send them to the power sampling sub-module;

[0013] The RF output circuit is used to output the RF signal.

[0014] Optionally, the RF control sub-module includes:

[0015] A bias control sub-module, connected to the RF module, is used to control the bias voltage of the RF module, and the bias voltage is used to control the bias voltage of the RF module to control the power of the RF signal;

[0016] A frequency control sub-module, connected to the RF module, is used to control the frequency of the RF signal.

[0017] Optionally, the preset frequency signal is a sine wave signal, and the frequency control sub-module includes:

[0018] A direct digital synthesis circuit, connected to the RF module and the processor module, is used to generate the sine wave signal;

[0019] A comparison circuit, connected to the direct digital synthesis circuit, is used to convert the sine wave signal into a square wave signal, and the square wave signal is used to control the output frequency of the RF module.

[0020] Optionally, the power sampling sub-module includes:

[0021] An input filter circuit, connected to the acquisition circuit, is used to filter the power feedback value;

[0022] An analog-to-digital conversion circuit, connected to the input filter circuit and the processor module, is used to perform analog-to-digital conversion on the filtered power feedback value, generate a digitalized power feedback value, and input the digitalized power feedback value into the processor module.

[0023] Optionally, the input filter module includes:

[0024] A filter circuit, connected to the acquisition circuit, is used to filter the power feedback value;

[0025] A multiplier circuit, connected to the filter circuit, is used to adjust the filtered power feedback value to a positive value.

[0026] Optionally, the input filtering module further includes:

[0027] A following circuit, located between the multiplier circuit and the analog-to-digital conversion circuit, for impedance matching of the signals between the multiplier circuit and the analog-to-digital conversion circuit.

[0028] Optionally, the input filtering module further includes:

[0029] A voltage dividing circuit, located between the filtering circuit and the multiplier circuit, for voltage dividing the multiplier circuit.

[0030] Optionally, the processor sub-module is further configured to receive a control mode signal,

[0031] When the control mode signal is efficiency priority, output the control signal to the power supply voltage control sub-module to control the radio frequency signal output by the radio frequency module through the DC output voltage; or

[0032] When the control mode signal is response time priority, output the control signal to the bias control sub-module to control the radio frequency signal output by the radio frequency module through the bias voltage.

[0033] In a second aspect of the present invention, an embodiment of the present invention discloses a semiconductor process equipment, including the radio frequency power supply, radio frequency matcher and process chamber as described above, and the radio frequency power supply is connected to the radio frequency electrode of the process chamber through the radio frequency matcher.

[0034] The embodiments of the present invention have the following advantages:

[0035] In the embodiments of the present invention, a power supply voltage control sub-module is connected to the switching power supply module for controlling the DC output voltage of the switching power supply module; a radio frequency control sub-module is connected to the radio frequency module for controlling the power and frequency of the radio frequency signal output by the radio frequency module; a power sampling sub-module is used to be connected to the radio frequency module for collecting the power feedback value of the radio frequency signal output by the radio frequency module; a processor sub-module is connected to the power supply voltage control sub-module, radio frequency control sub-module and the power sampling sub-module, and is configured to output control signals to the power supply voltage control sub-module and the radio frequency control sub-module based on the power feedback value and the frequency of the radio frequency signal, so that the radio frequency module outputs the required radio frequency signal. By controlling the voltage of the radio frequency module through the radio frequency control sub-module, the power and frequency of the radio frequency module can be quickly controlled, thereby reducing the response time. By controlling the DC output voltage output by the power supply voltage control sub-module of the switching power supply module and using a large voltage to control the radio frequency output, the switching power supply module can efficiently output voltage, so that the radio frequency module outputs the radio frequency power more stably, thereby improving the output efficiency. Brief Description of the Drawings

[0036] Figure 1 is a schematic block diagram of an embodiment of a radio frequency power supply according to the present invention;

[0037] Figure 2 is a schematic diagram of the principle of an embodiment of a radio frequency power supply according to the present invention;

[0038] Figure 3 is a schematic block diagram of the power supply voltage control sub-module according to the present invention;

[0039] Figure 4 is a schematic diagram of the principle of the power supply voltage control sub-module according to the present invention;

[0040] Figure 5 is a schematic block diagram of the bias voltage control sub-module according to the present invention;

[0041] Figure 6 is a schematic diagram of the principle of the bias voltage control sub-module according to the present invention;

[0042] Figure 7 is a schematic block diagram of the frequency control sub-module according to the present invention;

[0043] Figure 8 is a schematic diagram of the principle of the frequency control sub-module according to the present invention;

[0044] Figure 9 is a schematic block diagram of the power sampling sub-module according to the present invention;

[0045] Figure 10 is a schematic diagram of the principle of the power sampling sub-module according to the present invention;

[0046] Figure 11 is a schematic structural diagram of an embodiment of a semiconductor process equipment according to the present invention. Detailed Embodiments

[0047] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0048] Referring to Figure 1 , a schematic block diagram of an embodiment of a radio frequency power supply according to the present invention is shown, which may specifically include a control module 100, a switching power supply module 200, and a radio frequency module 300. The switching power supply 200 module is used to provide a controllable DC output voltage for the radio frequency module 300, and the radio frequency module 300 is used to output an adjustable radio frequency signal based on the DC output voltage.

[0049] The control module 100 includes:

[0050] The power supply voltage control sub-module 110, connected to the switching power supply 200 module, is used to control the DC output voltage of the switching power supply module 200;

[0051] The radio frequency control sub-module 120, connected to the radio frequency module 300, is used to control the power and frequency of the radio frequency signal output by the radio frequency module 300;

[0052] The power sampling sub-module 130, used to be connected to the radio frequency module 300, is used to collect the power feedback value of the radio frequency signal output by the radio frequency module 300;

[0053] The processor sub-module 140, connected to the power supply voltage control sub-module 110, the radio frequency control sub-module 120 and the power sampling sub-module 130, is used to output control signals to the power supply voltage control sub-module 110 and the radio frequency control sub-module 120 based on the power feedback value and the frequency of the radio frequency signal, so that the radio frequency module 300 outputs the required radio frequency signal.

[0054] The power supply voltage control sub-module 110 controls the DC output voltage of the switching power supply module 200 by outputting a voltage control signal. The radio frequency control sub-module 120 can directly output a control small voltage control signal to control the power and frequency of the radio frequency signal output by the radio frequency module 300. The power sampling sub-module 130 can collect the forward power and the reflected power as the power feedback value, and this power feedback value is used for the closed-loop control of the radio frequency.

[0055] In an embodiment of the present invention, a power supply voltage control sub-module 110 is connected to the switching power supply module 200 and is used to control the DC output voltage of the switching power supply module 200; a radio frequency control sub-module 120 is connected to the radio frequency module 300 and is used to control the power and frequency of the radio frequency signal output by the radio frequency module 300; a power sampling sub-module 130 is used to be connected to the radio frequency module 300 and is used to collect the power feedback value of the radio frequency signal output by the radio frequency module 300; a processor sub-module 140 is connected to the power supply voltage control sub-module 110, the radio frequency control sub-module 120 and the power sampling sub-module 130, and is used to output control signals to the power supply voltage control sub-module 110 and the radio frequency control sub-module 120 based on the power feedback value and the frequency of the radio frequency signal, so that the radio frequency module 300 outputs the required radio frequency signal. By controlling the voltage of the radio frequency module 300 through the radio frequency control sub-module 120, the power and frequency of the radio frequency module 300 can be quickly controlled, thereby reducing the response time. By controlling the DC output voltage output by the switching power supply module 200 through the power supply voltage control sub-module 110 and using a large voltage to control the radio frequency output, the switching power supply module 200 can efficiently output voltage, so that the radio frequency module 300 outputs the radio frequency power more stably, thereby improving the output efficiency.

[0056] Specifically, the radio frequency control sub-module 120 includes:

[0057] It can be referred to Figure 2 , a bias voltage control sub-module 121, which is connected to the radio frequency module 300 and is used to control the bias voltage of the radio frequency module 300, and the bias voltage is used to control the bias voltage of the radio frequency module 300 to control the power of the radio frequency signal;

[0058] a frequency control sub-module 122, which is connected to the radio frequency module 300 and is used to control the frequency of the radio frequency signal.

[0059] The radio frequency control sub-module 120 may specifically include a bias voltage control sub-module 121 and a frequency control sub-module 122. The bias voltage control sub-module 121 can control the bias voltage of the radio frequency module 300 through a bias voltage control signal, and control the power of the radio frequency signal by controlling the bias voltage of the radio frequency module 121 through the bias voltage. The frequency control sub-module 122 controls the frequency of the radio frequency output power based on the output DDS (Direct Digital Synthesis) frequency signal. By setting the frequency of the radio frequency output power, impedance matching can be achieved in the fastest 5 ms. The control module 100 can generate a radio frequency by the output of the frequency control sub-module.

[0060] For example, when the control module 100 receives the DDS frequency signal, it generates a square wave signal with a frequency of 13.56 MHz and an amplitude of ±5V. The square wave signal of 13.56 MHz is filtered into a sine wave signal of ±V5 through the filter circuit inside the RF circuit, and then amplified by the amplifier circuit inside the RF circuit to generate an RF power signal for output to the load. The amplification factor of the amplifier circuit varies according to the set power.

[0061] Specifically, the control module 100 may include a processor 140, which is connected to a power supply voltage control sub-module 110, a bias voltage control sub-module 121, a frequency control sub-module 122, and a power sampling sub-module 130. Among them, the control module may include an FPGA (Field-Programmable Gate Array), a CPLD (Complex Programmable Logic Device), a DSP (Digital Signal Processor), etc., which are not specifically limited in the embodiments of the present invention.

[0062] The specific connection relationship is that the processor 140 is connected to the power supply voltage control sub-module 110 to generate a power supply voltage control signal for controlling the switching power supply voltage, the processor 140 is connected to the bias voltage control sub-module 121 to generate a bias voltage control signal for controlling the RF output power, the processor 140 is connected to the frequency control sub-module 122 to generate a digital frequency signal for controlling the frequency of the RF output power, and the processor 140 is connected to the power sampling sub-module 130 to collect the feedback values of the forward power and the reflected power of the RF power output.

[0063] In an alternative embodiment of the present invention, referring to Figure 2 , the RF module 300 includes: an RF circuit 310, a sampling circuit 320, and an RF output circuit 330 connected in sequence; the RF circuit 30 is connected to the switching power supply module 200 and the RF control sub-module 121; the sampling circuit 320 is used to collect the feedback values of the forward power and the reflected power output by the RF circuit 310 and send them to the power sampling sub-module 130; the RF output circuit 330 is used to output the RF signal.

[0064] The DC output voltage provided by the switching power supply module 200, the bias voltage provided by the bias control sub-module 121, and the DDS frequency signal provided by the frequency control sub-module 122 can be used to generate the RF power output. The RF circuit 310 can generate an initial RF signal based on the DC output voltage of the switching power supply module 200 or the bias voltage output by the bias control sub-module 121. The RF circuit 310 determines the RF frequency based on the output of the frequency control sub-module 122.

[0065] The output end of the RF circuit 310 is connected to the input end of the sampling circuit 320, so as to sample the forward power and reflection power feedback values of the RF circuit 310 and provide them to the control module 100 to achieve closed-loop control. The output of the sampling circuit 320 is connected to the RF output end 330 to achieve the output of RF power. Among them, the closed-loop control can be the closed-loop control method used in actual applications, such as PID (Proportion, Integral, Differential) closed-loop control. Through the PID closed-loop control, the control period for RF control can be as short as 10 us at the shortest, shortening the control period and increasing the control frequency, thereby improving the dynamic response performance of the power supply.

[0066] Specifically, the processor sub-module 140 is further configured to receive a control mode signal. When the control mode signal is efficiency priority, it outputs the control signal to the power supply voltage control sub-module to control the RF signal output by the RF module 300 through the DC output voltage. When the control mode signal is response time priority, it outputs the control signal to the bias control sub-module 121 to control the RF signal output by the RF module 300 through the bias voltage.

[0067] In an alternative embodiment of the present invention, the power supply voltage control sub-module 110 can digitize the target power supply output voltage, and the power supply voltage control sub-module 110 is used to convert the digitized target power supply output voltage into an analog power supply output voltage signal to control the power supply output voltage.

[0068] Specifically, refer to Figure 2 , the control module 100 is connected to the switching power supply module 200 through the VBUS signal to control its DC output voltage. The switching power supply module 200 provides the DC output voltage for the RF module 300. The control module 100 is connected to the RF circuit 300 through the Bias signal and the DDS frequency signal to control its power and frequency. The forward power and reflection power feedback values provided by the RF module are sent to the control module for PID closed-loop control.

[0069] It can be referred to Figure 3, an alternative implementation of the power supply voltage control sub-module 110 according to an embodiment of the present invention is exemplarily shown. The power supply voltage control sub-module 110 includes a first digital-to-analog conversion circuit 111, a first digital-to-analog conversion output filtering circuit 112, and a first digital-to-analog conversion output interface 113. The processor 140 controls the digital-to-analog conversion circuit 1111 of the first digital-to-analog conversion circuit 111 to output a variable voltage value through the SPI interface. The voltage range is 0 to 2V. After passing through the follower circuit 1121 and the amplifier circuit 1122 of the first digital-to-analog conversion output filtering circuit 112, the output voltage range after being amplified by 2.5 times is 0 to 5V. After passing through the low-pass filtering circuit 1123 of the first digital-to-analog conversion output filtering circuit 112 to filter out high-frequency noise, it is output to the control interface of the switching power supply. The control voltage of 0 to 5V corresponds to the output voltage of the switching power supply of 0 to 100V. The voltage reference circuit 1112 provides a high-precision and low-temperature-drift voltage reference for the digital-to-analog conversion circuit 1111. Through the power supply voltage control sub-module 110, a high-power radio frequency signal can be quickly generated. Thus, when power control priority is required, power output control is performed through the power supply voltage control sub-module.

[0070] More specifically, as Figure 4, an alternative implementation of the power supply voltage control sub-module 110 according to an embodiment of the present invention is exemplarily shown, including a digital-to-analog conversion circuit 1111, a voltage reference circuit 1112, a follower circuit 1121, an amplifier circuit 1122, a low-pass filter circuit 1123, and a first digital-to-analog conversion output interface 130. The digital-to-analog conversion circuit 1111 includes a U3 chip, which is used to convert digital signals into analog voltage values. The set output range of the voltage is 0 to 2V. Its control terminal is connected to the processor 140, the voltage reference input terminal is connected to the voltage reference circuit, and the output terminal is connected to the follower circuit. The 2, 3, 4, and 5 pins of the U3 chip are the control pins of SPI and are respectively connected to the IO pins of the processor 140. The 6 pin of the U3 chip is the voltage reference input pin and is connected to the voltage reference output pin 2 of the voltage reference source U4. The 7 pin of the U3 is the analog voltage output pin and is connected to the non-inverting input terminal of the U2 chip. The 8 pin of the U3 chip is the power supply ground pin and is connected to GND. The 9 pin of the U3 chip is the power supply pin and is connected to the VCC power supply. The voltage reference circuit 1112 includes a U4 chip, which is used to provide a high-precision voltage reference source for the DAC chip. The output voltage reference is 2.5V. Its output terminal is connected to the digital-to-analog conversion circuit 1111. The 1 pin of the U4 chip is the power supply pin and is connected to the VCC power supply. The 3 pin of the U4 is the power supply ground input pin and is connected to GND. The 2 pin of the U4 chip is the reference voltage output pin, and the output voltage is 2.5V and is connected to the 6 pin of the U3. The follower circuit 1121 includes an operational amplifier U2 chip to achieve the follower function. The output range of the voltage is the same as the input range, which is 0 to 2V. Its output terminal is connected to the amplifier circuit 1122. The non-inverting input terminal 3 pin of the U2 chip is connected to the output of the digital-to-analog conversion circuit 1111. The 4 pin of the U2 chip is the power supply pin and is connected to VCC. The 8 pin of the U2 is the power supply ground pin and is connected to GND. The inverting input terminal 2 pin of the U2 is connected to the output pin 1 of the U2 chip. The output 1 pin of the U2 chip is connected to the subsequent amplifier circuit 1122. The amplifier circuit 1122 includes a U1 chip and resistors R1, R2, and R4, which achieve the function of amplifying the input voltage by 2.5 times. Its output range is 0 to 5V and is connected to the subsequent low-pass filter circuit 1123. The non-inverting input terminal 3 pin of the U3 chip is connected to one end of the matching resistor R4. The other end of the resistor R4 is connected to the output terminal of the follower circuit 1121. The inverting input terminal 2 pin of the U3 chip is respectively connected to the common terminal of the feedback resistor R2 and the resistor R1. The other end of the resistor R2 is connected to GND. The other end of the resistor R1 is connected to the output 1 pin of the U1 chip. The ratio of the feedback resistor R2 to the resistor R1 determines the amplification factor of the amplifier. In an example of this embodiment, the amplification factor is 2.By 5 times, the output voltage ranges from 0 to 5V. The low-pass filter circuit 1123 includes a resistor R3, a capacitor C1, and an inductor L1 to filter out high-frequency noise. Its output terminal is connected to the output control interface to the switching power supply module 200. One end of the output terminal of the amplifier circuit 1123 is connected to R3. The other end of R3 is connected to one end of C1, and then connected to one end of L1. The other end of C1 is connected to GND, and the other end of L1 is connected to the output interface 130.

[0071] Furthermore, the bias voltage control sub-module 121 is used to convert the digital target bias voltage into an analog bias voltage signal to control the bias voltage. Refer to Figure 5 , which exemplarily shows an optional implementation manner of the bias voltage control sub-module 121 of the embodiment of the present invention. The bias voltage control sub-module 121 includes a second digital-to-analog conversion circuit 1111, a second digital-to-analog conversion output filter circuit 1212, and a second digital-to-analog conversion output interface 1213. The processor 14 controls the analog-to-digital conversion circuit 12111 of the second digital-to-analog conversion circuit 1211 through the SPI interface to output a variable voltage value, and the voltage range is 0 to 2V. Then, through the follower circuit 12121 and the amplifier circuit 12122 of the second digital-to-analog conversion output filter circuit 1212, the output voltage range after being inversely amplified by 10 times is 11V to -9V, and then output to the second digital-to-analog conversion output interface 1213. By finely adjusting the bias voltage, rapid small-range power adjustment can be achieved. By directly switching to -11V, rapid shutdown of the radio frequency power can be achieved. By switching between the target voltage and -11V, stable output of high-frequency low-duty-cycle pulse power in pulse mode can be achieved.

[0072] More specifically, refer to Figure 6, an alternative implementation of the bias control sub-module according to an embodiment of the present invention is exemplarily shown, including the digital-to-analog conversion circuit 12111, voltage reference circuit 12112 of the second digital-to-analog conversion circuit 1211, the follower circuit 12121, amplifier circuit 12122 and output interface 1213 of the second digital-to-analog conversion output filter circuit 1212. The digital-to-analog conversion circuit 12111 of the second digital-to-analog conversion circuit 1211 includes chip U7, whose function is to convert digital signals into analog voltage values. The set output range of the voltage is 0 to 2V. Its control terminal is connected to the processor 140, the voltage reference input terminal is connected to the voltage reference circuit, and the output terminal is connected to the follower circuit 12121. The 2nd, 3rd, 4th, and 5th pins of U7 are the control pins of SPI and are respectively connected to the IO pins of the processor. The 6th pin of chip U7 is the input pin for power reference and is connected to the voltage reference output pin 2 of the voltage reference source U8. The 7th pin of chip U8 is the output pin for analog voltage and is connected to the inverting input terminal of chip U6. The 8th pin of chip U7 is the ground pin for power supply and is connected to GND. The 9th pin of chip U7 is the power supply pin for power supply and is connected to the VCC power supply. The voltage reference circuit 12112 includes chip U8, whose function is to provide a high-precision voltage reference source for the DAC chip. The output voltage reference is 2.5V. Its output terminal is connected to the DAC circuit. The 1st pin of chip U8 is the power supply pin for power supply and is connected to the VCC power supply. The 3rd pin of chip U8 is the ground input pin for power supply and is connected to GND. The 2nd pin of chip U8 is the output pin for the reference voltage, and the output voltage is 2.5V and is connected to the 6th pin of U7. The follower circuit 12121 includes the operational amplifier chip U6 to achieve the follower function. The output range of the voltage is the same as the input range, which is 0 to 2V. Its output terminal is connected to the amplifier circuit. The amplifier circuit 12122 is composed of chip U5, resistor R5, resistor R6, resistor R8, and resistor R16. The inverting input terminal 2 of chip U5 is connected to the output of the digital-to-analog conversion circuit 12111 through resistor R6 and is connected to the output terminal 1 of chip U6 through resistor R5. The feedback resistors R5 and R6 determine the amplification factor of the amplifier. The bias voltage is connected to the non-inverting input terminal 3 of chip U5 after being divided by chip R8 and chip R6. The 4th pin of chip U5 is the power supply pin for power supply and is connected to VCC. The 8th pin of chip U5 is the ground pin for power supply and is connected to GND. The output voltage range of the amplifier circuit 12122 is 11 to -9V and is connected to the output interface through resistor R7.

[0073] In an alternative embodiment of the present invention, the preset frequency signal is a sine wave signal, and the frequency control sub-module 122 includes:

[0074] A direct digital synthesis circuit 1221, connected to the radio frequency module 300 and the processor module 140, for generating the sine wave signal;

[0075] A comparison circuit 1222, connected to the direct digital synthesis circuit 1221, is configured to convert the sine wave signal into a square wave signal, and the square wave signal is used to control the output frequency of the radio frequency module 300.

[0076] The frequency control sub-module includes a direct digital synthesis circuit 1221 and a comparison circuit 1222. The direct digital synthesis circuit 1221 emits a sine wave signal through its own clock. The comparison circuit 1222 compares the reference signal with the sine wave signal to generate a square wave signal. Based on the square wave signal as a digital quantity, the output frequency of the radio frequency module 300 is controlled. By setting different frequencies through the frequency control sub-module, the function of fast frequency scanning can be achieved.

[0077] Referring to Figure 7 , an optional implementation manner of the frequency control sub-module 122 of the embodiment of the present invention is exemplarily shown, including a direct digital synthesis circuit 1221, a comparison circuit 1222, and a direct digital synthesis output interface 1223. The processor 140 controls the direct digital synthesis circuit 1221 to output sine waves with different frequencies and phases through the SPI interface. The frequency range is 20 - 30 MHz, and the phase range is 0 - 360 degrees. A filter circuit 1224 can also be set in the frequency control sub-module 122. The signal passes through the filter circuit 1224 to filter out high-frequency noise, and the square wave output is achieved through the comparison circuit 1222. Finally, through the direct digital synthesis 1223, the output of a square wave with an adjustable frequency range of 20 - 30 MHz, a phase of 0 - 360 degrees, and a duty cycle of 50% is realized.

[0078] More specifically, reference can be made to Figure 8, an alternative implementation of the frequency control sub-module 122 according to an embodiment of the present invention is exemplarily shown. The direct digital synthesis circuit 1221 includes a comparison chip U12, a crystal oscillator Y1, a resistor R12, and a resistor R13, and realizes the output of sine waves with different frequencies and phases through digital control. The output frequency range is 25.764 - 28.476 MHz, and the output phase range is 0 - 360 degrees. Its control terminal is connected to the processor 140, and the output terminal is connected to the filter circuit. The 39th, 40th, 41st, and 36th pins of U12 are the control pins of SPI and are respectively connected to the IO pins of the FPGA. The 6th pin of U12 is the input pin of the crystal oscillator clock and is connected to the 3rd output pin of the crystal oscillator Y1. The 4th pin of Y1 is the power supply pin for power supply and is connected to the VCC power supply. The 1st pin of Y1 has no electrical connection. The 2nd pin of Y1 is the ground pin for power supply and is connected to GND. The 43rd pin of U12 is the power supply pin for the control interface and is connected to the VCC power supply. The 42nd pin of U12 is the ground pin for the control interface and is connected to GND. The 21st pin of U12 outputs the positive signal of the differential signal through the pull-up resistor R12. The 20th pin of U12 outputs the negative signal of the differential signal through the pull-up resistor R13. The positive and negative ends of the differential signal are respectively connected to the filter circuit 1224 of the frequency control sub-module 122. The filter circuit 1224 includes an inductor L4, capacitors C5, C6, an inductor L3, and an inductor L5. Its main function is to filter out high-frequency noise signals. The inductor L4 is connected in parallel to the positive and negative ends of the differential signal and is connected in parallel with the two ends of C5 and C6. After being respectively connected in series with L3 and L5, it is output to the 3rd and 4th pins of U13. The comparison circuit 1222 includes a U13 chip, and its main function is to realize the conversion from sine wave input to square wave output. The positive input 3rd pin of the U13 chip is connected to the positive end of the differential signal output by the filter circuit. The negative input 4th pin of the U13 chip is connected to the negative end of the differential signal output by the filter circuit. The 5th pin of the U13 chip is the power supply pin for power supply and is connected to the VCC power supply. The 2nd pin of the U13 chip is the ground pin for power supply and is connected to GND. The output pin 1 of U13 is connected to the direct digital synthesis output interface 1223 through a series resistor R14, realizing the output of a square wave with an adjustable frequency range of 20 - 30 MHz, a phase of 0 - 360 degrees, and a duty cycle of 50%.

[0079] In an alternative embodiment of the present invention, the power sampling sub-module 130 includes:

[0080] An input filter circuit 132, connected to the acquisition circuit 321, for filtering the power feedback value;

[0081] An analog-to-digital conversion circuit 131, connected to the input filter circuit 132 and the processor 140, for performing analog-to-digital conversion on the filtered power feedback value to generate a digitized power feedback value, and inputting the digitized power feedback value into the processor 140.

[0082] Reference may be made to Figure 9 , which exemplarily shows an alternative implementation of the power sampling sub-module 130 according to an embodiment of the present invention. The signal acquisition input interface 133 is connected to the AC voltage signal coupled by the directional coupler. After the high-frequency noise and DC components are filtered out by the input filter circuit 132, the voltage is controlled within a reasonable range by the voltage division circuit 134. The signal of the squared voltage is obtained through the multiplier 135, which is in a proportional relationship with the power. After being rectified into a DC signal by the low-pass filter circuit 136, and through the follower circuit 137 to increase its driving ability, the analog voltage is converted into a digital quantity by the analog-to-digital conversion circuit 131 and input into the processor 140 through the differential SPI signal, so as to realize real-time power sampling.

[0083] More specifically, reference may be made to Figure 10, an optional implementation manner of the power sampling sub-module according to an embodiment of the present invention is exemplarily shown, including a signal acquisition input interface 133, a filtering circuit 132, a voltage dividing circuit 134, a multiplier circuit 135, a low-pass filtering circuit 136, a follower circuit 137, and an analog-to-digital conversion circuit 131. The filtering circuit 132 includes a capacitor C2, an inductor L2, and a capacitor C3, and its function is to filter out high-frequency noise and low-frequency DC components. The AC signal coupled by the directional coupler is connected through the series-connected capacitor C2 and inductor L2. One end of the inductor L2 is connected to one end of the capacitor C3, and the other end of the capacitor C3 is connected to GND. The output of the filtering circuit 132 is connected to the input of the voltage dividing circuit 134. The voltage dividing circuit 134 is composed of a resistor R9 and a resistor R10, and its output voltage is controlled within a reasonable range. The sampling signal is input through one end of the resistor R9. One end of the resistor R9 is connected to R10 and then output to the 5th pin of the U9 chip. The other end of the resistor R10 is connected to GND. The multiplier circuit 135 is composed of the U9 chip. The function realized by the multiplier circuit 135 is that the output signal is proportional to the square of the input signal. Since the square of the AC voltage coupled by the directional coupler is proportional to the power, it can be obtained that the signal output by the multiplier circuit 135 is proportional to the power. The 11th pin of the U9 chip is the positive power supply pin for power supply and is connected to the VCC power supply. The 7th pin of the U9 chip is the negative power supply pin for power supply and is connected to the -VCC power supply. The 1st pin of the U9 is the ground pin for power supply and is connected to GND. The 2nd, 3rd, 4th, 14th, 15th, and 16th pins of the U9 chip have no electrical connection. The output signal of the multiplier circuit 135 is connected to the low-pass filtering circuit 136. The low-pass filtering circuit 136 is composed of a resistor R11 and a capacitor C4. One end of the resistor R11 is connected to the 9th pin of the output of the chip U11. The other end of the resistor R11 is connected to the capacitor C4 and then output to the non-inverting input terminal 3rd pin of the U10 chip of the follower circuit 137. The other end of the C4 is connected to GND. The follower circuit 137 is composed of the U10 chip, and its main function is to realize impedance matching between the input and output and increase the driving ability. The inverting input terminal 2nd pin of the U10 chip is connected to the output 1st pin of the U10 and then output to the voltage input terminal of the ADC chip of the analog-to-digital conversion circuit 133. The 4th pin of the U10 is the positive power supply pin for power supply and is connected to the VCC power supply. The 8th pin of the U10 is the ground pin for power supply and is connected to GND. The analog-to-digital conversion circuit 131 is composed of the U11 chip, and its main function is to collect the voltage signals of the forward power and the reflected power, convert them into digital signals, and output them to the processor 140. The 2nd pin of the U11 chip is connected to the voltage signal coupled from the forward power. The 3rd pin of the U11 chip is connected to GND. The 4th pin of the U11 chip is connected to the voltage signal coupled from the reflected power. The 5th pin of the U11 chip is connected to GND. The 15th, 16th, 19th, 20th, 21st, and 22nd pins of the U11 chip are SPI interfaces and are connected to the IO ports of the processor 140. The 28th pin of the U11 chip is the input of the reference voltage and is connected to the VCC power supply.Pins 9, 13, 17, 18, 24, and 25 of U11 have no electrical connection.

[0084] It should be noted that, for the method embodiments, for simplicity of description, they are all expressed as a series of action combinations. However, those skilled in the art should know that the embodiments of the present invention are not limited by the described action sequences, because according to the embodiments of the present invention, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions involved are not necessarily essential for the embodiments of the present invention.

[0085] Refer to Figure 11 , which shows a schematic structural diagram of an embodiment of a semiconductor process equipment of the present invention. The semiconductor process equipment specifically includes: the radio frequency power supply 1, the radio frequency matcher 2, and the process chamber 3 as described above. The radio frequency power supply 1 is connected to the radio frequency electrode of the process chamber 3 through the radio frequency matcher 2.

[0086] When the radio frequency power supply 1 is powered on, it emits radio frequency signals. The radio frequency signals pass through the radio frequency matcher 2, and the radio frequency matcher 2 performs impedance matching and loads the matched radio frequency signals onto the radio frequency electrode of the process chamber 3, so that plasma can be excited and ionized in the process chamber 3 to process the wafer to be processed.

[0087] Each embodiment in this specification is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other.

[0088] Those skilled in the art should understand that the embodiments of the present invention can be provided as methods, devices, or computer program products. Therefore, the embodiments of the present invention can take the form of completely hardware embodiments, completely software embodiments, or embodiments combining software and hardware aspects. Moreover, the embodiments of the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memories, CD-ROMs, optical memories, etc.) containing computer-usable program codes.

[0089] Embodiments of the present invention are described with reference to the flowcharts and / or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, and the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing terminal device to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing terminal device generate a device for implementing the functions specified in one process Figure 1 one process or multiple processes and / or blocks Figure 1 or multiple blocks.

[0090] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing terminal device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including an instruction device that implements the functions specified in one process Figure 1 one process or multiple processes and / or blocks Figure 1 or multiple blocks.

[0091] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal device, such that a series of operation steps are executed on the computer or other programmable terminal device to generate a computer-implemented process, so that the instructions executed on the computer or other programmable terminal device provide steps for implementing the functions specified in one process Figure 1 one process or multiple processes and / or blocks Figure 1 or multiple blocks.

[0092] Although the preferred embodiments of the embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications once they learn the basic creative concepts. Therefore, the appended claims are intended to be construed as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0093] Finally, it should also be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article or terminal device comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or terminal device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or terminal device comprising said element.

[0094] The above has introduced in detail a radio frequency power supply and a semiconductor process device provided by the present invention. Specific examples are used in this text to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A radio frequency power supply, characterized in that: include: A control module, a switching power supply module and a radio frequency module, wherein the switching power supply module is used to provide a DC output voltage to the radio frequency module, and the radio frequency module is used to output a required radio frequency signal; The control module comprises: A power supply voltage control submodule, connected to the switching power supply module, and used to control the DC output voltage of the switching power supply module; A radio frequency control submodule, connected to the radio frequency module, and used to control the power and frequency of the radio frequency signal output by the radio frequency module; A power sampling submodule, used to connect to the radio frequency module and collect the power feedback value of the radio frequency signal output by the radio frequency module; The processor submodule is connected to the power supply voltage control submodule, the RF control submodule and the power sampling submodule, and is used to output a control signal to the power supply voltage control submodule and the RF control submodule based on the power feedback value and the frequency of the RF signal, so that the RF module outputs the required RF signal.

2. The radio frequency power supply according to claim 1, characterized in that: The radio frequency module comprises: a radio frequency circuit, a collection circuit and a radio frequency output circuit connected in sequence; The radio frequency circuit is connected to the switching power supply module and the radio frequency control submodule; The sampling circuit is used to collect feedback values ​​of the forward power and reflected power output by the radio frequency circuit, and send them to the power sampling submodule; The radio frequency output circuit is used to output the radio frequency signal.

3. The radio frequency power supply according to claim 1 or 2, characterized in that: The radio frequency control submodule includes: A bias control submodule, connected to the RF module, and used to control the bias voltage of the RF module, wherein the bias voltage is used to control the bias voltage of the RF module to control the power of the RF signal; The frequency control submodule is connected to the radio frequency module and is used to control the frequency of the radio frequency signal.

4. The radio frequency power supply according to claim 3, characterized in that: The preset frequency signal is a sine wave signal, and the frequency control submodule includes: A direct digital synthesis circuit, connected to the radio frequency module and the processor module, for emitting the sinusoidal wave signal; A comparison circuit is connected to the direct digital synthesis circuit and is used to convert the sine wave signal into a square wave signal, and the square wave signal is used to control the output frequency of the radio frequency module.

5. The radio frequency power supply according to claim 2, characterized in that: The power sampling submodule comprises: An input filter circuit, connected to the acquisition circuit, and used for filtering the power feedback value; The analog-to-digital conversion circuit is connected to the input filtering circuit and the processor module, and is used to perform analog-to-digital conversion on the filtered power feedback value to generate a digitized power feedback value, and input the digitized power feedback value into the processor module.

6. The radio frequency power supply according to claim 5, characterized in that: The input filtering module comprises: A filtering circuit, connected to the acquisition circuit, for filtering the power feedback value; The multiplier circuit is connected to the filter circuit and is used to adjust the filtered power feedback value to a positive value.

7. The radio frequency power supply according to claim 6, characterized in that: The input filtering module also includes: The follower circuit is located between the multiplier circuit and the analog-to-digital conversion circuit and is used for impedance matching between the multiplier circuit and the signal of the analog-to-digital conversion circuit.

8. The radio frequency power supply according to claim 6, characterized in that: The input filtering module also includes: The voltage divider circuit is located between the filter circuit and the multiplier circuit and is used for performing voltage division on the multiplier circuit.

9. The radio frequency power supply according to claim 3, characterized in that: The processor submodule is also used to receive a control mode signal, When the control mode signal is efficiency priority, outputting the control signal to the power supply voltage control submodule to control the radio frequency signal output by the radio frequency module through the DC output voltage; or When the control mode signal is response time priority, the control signal is output to the bias control submodule to control the radio frequency signal output by the radio frequency module through the bias voltage.

10. A semiconductor process equipment, characterized in that: It comprises the radio frequency power supply, radio frequency matcher and process chamber as described in claims 1 to 9, wherein the radio frequency power supply is connected to the radio frequency electrode of the process chamber through the radio frequency matcher.

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