Radio frequency power supply and semiconductor process equipment

Abstract

The utility model provides a radio frequency power supply and semiconductor process equipment. The radio frequency power supply comprises a driving module, a power amplifier module and a filtering module which are connected in sequence, the driving module is used for outputting a driving signal, and the power amplifier module is used for outputting a radio frequency signal under the excitation of the driving signal; the filtering module comprises a first filtering synthesis unit, the input end of which is connected with the output end of the power amplifier module, and the first filtering synthesis unit is used for filtering interference signals in the radio frequency signals; the input end of the second filtering synthesis unit is connected with the output end of the first filtering synthesis unit, and the second filtering synthesis unit is used for carrying out secondary filtering on the radio frequency signal output by the first filtering synthesis unit; the input end of the synthesis output filtering unit is connected with the output end of the second filtering synthesis unit, and the synthesis output filtering unit is used for compensating the radio frequency power output by the second filtering synthesis unit; according to the embodiment of the utility model, the output power can be stabilized under the condition that the impedance of the high standing wave chamber is frequently changed; therefore, the etching uniformity and the etching efficiency can be ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor process equipment, in particular to a radio frequency power supply and a semiconductor process equipment. Background Art

[0002] During the semiconductor wafer processing process, RF energy needs to be stably input into the process chamber to maintain the plasma state inside the process chamber, so as to perform semiconductor wafer etching. In the process of generating plasma, the RF power supply needs to provide RF energy with a pure main frequency and stable output power. At present, the synthetic filtering method is often used for RF output. Due to the differences in cable length and process formula in actual application, RF power mismatch is more likely to occur in different machines or chambers. For example, it is difficult to stabilize the output power under the condition of frequent changes in high standing wave chamber impedance. Due to the instability of the output power, the etching process is unstable, resulting in low etching uniformity and etching efficiency. Utility Model Content

[0003] In view of the above problems, the present invention is proposed to provide a radio frequency power supply and a semiconductor process equipment that overcome the above problems or at least partially solve the above problems.

[0004] In order to solve the above problems, in a first aspect of the present invention, the present invention discloses a radio frequency power supply, comprising: a driving module, a power amplifier module and a filtering module connected in sequence; the driving module is used to output a driving signal, the power amplifier module is used to output a radio frequency signal under the excitation of the driving signal; the filtering module includes:

[0005] a first filtering and synthesizing unit, whose input end is connected to the output end of the power amplifier module and is used to filter out interference signals in the radio frequency signal;

[0006] a second filtering and synthesizing unit, whose input end is connected to the output end of the first filtering and synthesizing unit, and is used to perform secondary filtering on the radio frequency signal output by the first filtering and synthesizing unit;

[0007] The synthesis output filter unit has an input end connected to the output end of the second filtering synthesis unit and is used to compensate for the radio frequency power output by the second filtering synthesis unit.

[0008] Optionally, the first filtering synthesis unit is a bandpass filtering synthesis unit, whose input end is connected to the output end of the power amplifier module, and is used to select the radio frequency signal corresponding to the target frequency; the second filtering synthesis unit is a low-pass filtering synthesis unit, whose input end is connected to the output end of the bandpass filtering synthesis unit, and is used to filter out the harmonics of the radio frequency signal corresponding to the target frequency; or

[0009] The first filtering synthesis unit is a low-pass filtering synthesis unit, whose input end is connected to the output end of the power amplifier module, and is used to filter out the harmonics in the radio frequency signal; the second filtering synthesis unit is a band-pass filtering synthesis unit, whose input end is connected to the output end of the low-pass filtering synthesis unit, and is used to select the radio frequency signal corresponding to the target frequency after filtering out the harmonics.

[0010] Optionally, the bandpass filter synthesis unit includes at least one bandpass filter synthesis circuit, the number of the bandpass filter synthesis circuits matches the number of the power amplifier modules and the bandpass filter synthesis circuits are connected to the output end of the corresponding power amplifier module.

[0011] Optionally, the bandpass filter synthesis circuit includes:

[0012] a first inductor, one end of which is connected to the power amplifier module;

[0013] a first capacitor, one end of which is connected to the other end of the first inductor and the other end of which is grounded;

[0014] a second inductor, one end of which is connected between the first inductor and the first capacitor;

[0015] a first resistor, one end of which is connected to the other end of the second inductor;

[0016] a second capacitor, one end of which is connected to the other end of the first resistor and the other end of which is grounded;

[0017] a third capacitor connected in parallel across the second inductor;

[0018] The first inductor, the first capacitor, the second inductor, and the third capacitor are used together to select a radio frequency signal corresponding to a target frequency or to select a radio frequency signal corresponding to the target frequency after filtering out harmonics, wherein the target frequency is determined by the inductance value of the first inductor, the capacitance value of the first capacitor, the inductance value of the second inductor, and the capacitance value of the third capacitor;

[0019] The first resistor, the second capacitor, the second inductor and the third capacitor are used together to release radio frequency energy of the radio frequency signal input to the bandpass filter synthesis circuit to protect the bandpass filter synthesis circuit.

[0020] Optionally, the bandpass filtering synthesis circuit further includes:

[0021] a fourth capacitor, one end of which is connected to the other end of the first inductor, one end of the first capacitor, one end of the second inductor, and one end of the third capacitor, and the other end of which is connected to the low-pass filtering unit, for buffering RF energy in the first inductor, the first capacitor, the second inductor, and the third capacitor.

[0022] Optionally, the first inductor and the second inductor are microstrip line inductors.

[0023] Optionally, the low-pass filtering synthesis module includes at least one resistor-capacitor filtering circuit, the number of which matches the number of the band-pass filtering synthesis units, and the resistor-capacitor filtering circuit includes:

[0024] a second resistor, one end of which is connected to the bandpass filter synthesis unit, and the other end of which is connected to the synthesis output filter unit;

[0025] a fifth capacitor, one end of which is connected to the other end of the second resistor and the synthesis output filtering synthesis module, and the other end of which is grounded;

[0026] The second resistor and the fifth capacitor are used together to filter out the harmonics of the radio frequency signal corresponding to the target frequency, or to filter out the harmonics in the radio frequency signal.

[0027] Optionally, the synthesis output filtering unit includes:

[0028] A symmetrical network circuit is connected to the second filtering and synthesizing unit and is used to compensate for the radio frequency power output by the second filtering and synthesizing unit.

[0029] Optionally, the symmetrical network circuit includes:

[0030] A third inductor, one end of which is connected to the low-pass filter synthesis module and the other end of which is output;

[0031] a sixth capacitor, one end of which is connected to one end of the third inductor and the other end of which is grounded;

[0032] a seventh capacitor, one end of which is connected to the other end of the third inductor and the other end of which is grounded;

[0033] The third inductor, the sixth capacitor and the seventh capacitor are used together to filter out reflected waves in the radio frequency signal output by the second filtering and synthesizing unit;

[0034] The third inductor and the seventh capacitor are used together to compensate for the radio frequency power output by the second filtering and combining unit.

[0035] In the second aspect of the present invention, the present invention discloses a semiconductor process equipment, which includes a radio frequency power supply, a radio frequency matcher, and a process chamber. The radio frequency power supply is the above-mentioned radio frequency power supply, and the radio frequency power supply is used to output radio frequency power to the electrode of the process chamber. The radio frequency matcher is used to load the radio frequency power to the process chamber to excite the process gas in the process chamber to form plasma; the process chamber is used to process the wafer to be processed based on the plasma.

[0036] The utility model has the following advantages:

[0037] The embodiment of the present invention filters out low-frequency interference by using a first filtering synthesis unit and a second filtering synthesis unit. When using RF power supplies of different frequencies in the same process chamber, it can effectively prevent the backflow of power of other frequencies and protect the power amplifier module; by using a synthetic output filter module to compensate for the output RF power, the output power stability of the RF power supply under high standing waves and frequent changes in chamber impedance is improved; the filter composed of the first filtering synthesis unit, the second filtering synthesis unit and the synthetic output filter unit can effectively suppress harmonics, thereby reducing the interference signal in the RF signal output by the RF power supply; after receiving the RF signal output by the RF power supply, the matcher can accurately perform impedance matching, making the RF power matching more accurate and the RF power input into the process chamber more stable, thereby ensuring the etching uniformity and etching efficiency of the etching process. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a structural block diagram of a radio frequency power supply of the utility model;

[0039] Figure 2 This is a structural block diagram of an example of a radio frequency power supply of the present invention;

[0040] Figure 3 This is a structural block diagram of another example of a radio frequency power supply of the present invention;

[0041] Figure 4 This is a structural block diagram of another example of a radio frequency power supply of the present invention;

[0042] Figure 5 This is a circuit diagram of a radio frequency power supply of the utility model;

[0043] Figure 6 This is a schematic diagram of output test results of a radio frequency power supply of the present invention;

[0044] Figure 7 This is a structural block diagram of a semiconductor process equipment of the present invention. DETAILED DESCRIPTION

[0045] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0046] Reference Figure 1, shows a structural block diagram of a radio frequency power supply of the present invention, which may specifically include: a driving module 100, a power amplifier module 200 and a filtering module 300 connected in sequence; the driving module 100 is used to output a driving signal, and the power amplifier module 200 is used to output a radio frequency signal under the excitation of the driving signal.

[0047] The filtering module 300 includes:

[0048] A first filtering and synthesizing unit 310, whose input end is connected to the output end of the power amplifier module 200, is used to filter out interference signals in the radio frequency signal;

[0049] a second filtering and synthesizing unit 320, whose input end is connected to the output end of the first filtering and synthesizing unit 310, and is configured to perform secondary filtering on the RF signal output by the first filtering and synthesizing unit 310;

[0050] The synthesis output filtering unit 330 has an input end connected to the output end of the second filtering synthesis unit 320 and is used to compensate for the RF power output by the second filtering synthesis unit 320 .

[0051] Since the present invention provides a solution for the impedance mismatch situation, the synthesis output filter unit 330 specifically compensates for the RF power output by the second filter synthesis unit 320 when the impedance is not 50Ω.

[0052] In an embodiment of the present invention, the filter module 300 may be composed of a first filter synthesis unit 310, a second filter synthesis unit 320, and a synthesis output filter unit 330. The first filter synthesis unit 310, the second filter synthesis unit 320, and the synthesis output filter unit 330 are connected in sequence. The input end of the first filter synthesis unit 310 is the input end of the filter module 300, which receives the radio frequency signal output by the power amplifier module 200 and filters out the interference signal in the radio frequency signal. The second filter synthesis unit 320 then performs secondary filtering on the radio frequency signal output by the first filter synthesis unit 310. The specific filtering form of the secondary filtering is coordinated with the filtering of the first filter synthesis unit 310. For example, when the first filter synthesis unit 310 performs low-pass filtering, the secondary filtering performs band-pass filtering. Or when the first filter synthesis unit 310 performs band-pass filtering, the secondary filtering performs low-pass filtering. The first filter synthesis unit 310 and the second filter synthesis unit 320 filter and suppress the various harmonics or high-frequency interference in the radio frequency signal, reduce the clutter in the radio frequency signal after filtering by the first filter synthesis unit 310 and the second filter synthesis unit 320, ensure that the radio frequency signal is maintained at the main frequency, and thus ensure the stability of the output of the radio frequency signal.

[0053] Finally, the synthesis output filter unit 330 is used as the final filter to synthesize and filter the RF signal output by the second filter synthesis unit 320. The synthesis output filter unit 330 adopts a symmetrical filtering structure, and the power output is compensated, thereby improving the output power stability of the power supply under high standing waves and frequent changes in cavity impedance.

[0054] The embodiment of the present invention filters out low-frequency interference by using the first filter synthesis unit 310 and the second filter synthesis unit 320. When different frequency RF power supplies are used in the same process chamber, it can effectively prevent the backflow of other frequency powers and protect the power amplifier module 200. The symmetry of the synthetic output filter module 300 is used to compensate for the power output, thereby improving the output power stability of the RF power supply under high standing waves and frequent changes in chamber impedance. The filter composed of the first filter synthesis unit 310, the second filter synthesis unit 320 and the synthetic output filter unit 330 can effectively suppress harmonics, thereby reducing the interference signal in the RF signal output by the RF power supply. After receiving the RF signal output by the RF power supply, the matcher can accurately perform impedance matching, making the RF power matching more accurate and the RF power input to the process chamber more stable, thereby ensuring the etching uniformity and etching efficiency of the etching process.

[0055] Specifically, please refer to Figure 2 , shows a structural block diagram of an example of a radio frequency power supply of the present invention; the first filtering synthesis unit 310 is a bandpass filtering synthesis unit 340, whose input end is connected to the output end of the power amplifier module 200, and is used to select the radio frequency signal corresponding to the target frequency; the second filtering synthesis unit 320 is a low-pass filtering synthesis unit 350, whose input end is connected to the output end of the bandpass filtering synthesis unit 340, and is used to filter out the harmonics of the radio frequency signal corresponding to the target frequency.

[0056] In this example, the first filter synthesis unit 310 is a bandpass filter synthesis unit 340, and the second filter synthesis unit 320 is a low-pass filter synthesis unit 350. That is, the filtering module 300 performs primary bandpass filtering through the bandpass filter synthesis unit 340, secondary low-pass filtering through the low-pass filter synthesis unit 350, and final output filtering through the synthesis output filter unit 330. The bandpass filter synthesis unit 340, the low-pass filter synthesis unit 350, and the synthesis output filter unit 330 are connected in sequence; that is, the input end of the bandpass filter synthesis unit 340 is connected to the output end of the power amplifier unit, the input end of the low-pass filter synthesis unit 350 is connected to the output end of the bandpass filter synthesis unit 340, and the input end of the synthesis output filter unit 330 is connected to the output end of the low-pass filter synthesis unit 350.

[0057] The bandpass filter synthesis unit 340 can filter out the interference frequency in the RF signal and only pass the frequency corresponding to the target working RF power. For example, all frequencies other than the frequency corresponding to the target working RF power can be filtered out as interference frequencies. The frequency corresponding to the target working RF power is determined according to actual conditions, including but not limited to 2MHz, 13.56MHz, 27.12MHz, and 40.68MHz. The low-pass filter synthesis unit 350 can filter out each harmonic in the RF signal and suppress high-order harmonics to ensure the purity of the RF power. The synthesis output filter unit 330 serves as the final filter to synthesize the RF signal output by the low-pass filter synthesis unit 350, and uses its own symmetry to compensate for the power output, thereby improving the output power stability of the power supply under high standing waves and frequent changes in cavity impedance.

[0058] In another example, refer to Figure 3 , shows a structural block diagram of another example of a radio frequency power supply of the present invention; the first filtering synthesis unit 310 is a low-pass filtering synthesis unit 350, whose input end is connected to the output end of the power amplifier module 200, and is used to filter out the harmonics in the radio frequency signal; the second filtering synthesis unit 320 is a band-pass filtering synthesis unit 340, whose input end is connected to the output end of the low-pass filtering synthesis unit 350, and is used to select the radio frequency signal corresponding to the target frequency after filtering out the harmonics.

[0059] In this example, the first filter synthesis unit 310 is a low-pass filter synthesis unit 350, and the second filter synthesis unit 320 is a band-pass filter synthesis unit 340. That is, the RF signal output by the power amplifier module 200 is first low-pass filtered, then band-pass filtered, and finally subjected to final filtering. Specifically, the low-pass filter synthesis unit 350 is connected to the output of the power amplifier unit, the band-pass filter synthesis unit 340 is connected to the output of the low-pass filter synthesis unit 350, and the synthesis output filter unit 330 is connected to the output of the band-pass filter synthesis unit 340. The low-pass filter synthesis unit 350, the band-pass filter synthesis unit 340, and the synthesis output filter unit 330 are connected in series to form a filter. The RF signal output by the power amplifier unit first enters the low-pass filter synthesis unit 350 for low-pass filtering to filter out the harmonics in the RF signal; then enters the band-pass filter synthesis module for band-pass filtering to filter out interference frequencies in the RF signal; and finally enters the band-pass filter synthesis unit 340 for synthesis and filtering.

[0060] In an optional embodiment of the present invention, referring to Figure 4The low-pass filtering synthesis unit 350 may be a single low-pass filtering synthesis unit 350. That is, multiple band-pass filtering synthesis units 340 are connected to one low-pass filtering synthesis unit 350, and the single low-pass filtering synthesis unit 350 performs low-pass filtering, thereby achieving miniaturization of the structure, reducing the volume of the RF power supply, and saving costs.

[0061] In an optional embodiment of the present invention, the bandpass filter synthesis unit 340 includes at least one bandpass filter synthesis circuit 341. The number of the bandpass filter synthesis circuits 341 matches the number of the power amplifier modules 200, and the bandpass filter synthesis circuits 341 are connected to the output terminals of their corresponding power amplifier modules 200. That is, the input terminals of the bandpass filter synthesis circuits 341 are connected to the output terminals of their corresponding power amplifier modules 200.

[0062] In practical applications, the number of bandpass filter synthesis units 340 can be the same as the number of power amplifier modules 200. The RF signal output by each power amplifier module 200 is bandpass filtered by its uniquely corresponding bandpass filter synthesis circuit 341. When different frequency RF power sources are used in the same process chamber, the bandpass filter synthesis circuit 341 can effectively prevent the backflow of power from other frequencies, protecting the power amplifier module 200 and preventing damage to the power amplifier module 200. Each bandpass filter synthesis circuit 341 in the bandpass filter synthesis unit 340 is identical.

[0063] Specifically, please refer to Figure 5 , the bandpass filter synthesis circuit 341 includes:

[0064] A first inductor S111, one end of which is connected to the power amplifier module 200;

[0065] a first capacitor S112, one end of which is connected to the other end of the first inductor S111, and the other end of which is grounded;

[0066] a second inductor S113, one end of which is connected between the first inductor S111 and the first capacitor S112;

[0067] a first resistor S115, one end of which is connected to the other end of the second inductor S113;

[0068] a second capacitor S116, one end of which is connected to the other end of the first resistor S115, and the other end of which is grounded;

[0069] a third capacitor S114 connected in parallel to both ends of the second inductor S113;

[0070] The first inductor S111, the first capacitor S112, the second inductor S113, and the third capacitor S114 are jointly used to select the radio frequency signal corresponding to the target frequency or the radio frequency signal corresponding to the target frequency after filtering out each harmonic, and the target frequency is determined by the inductance value of the first inductor, the capacitance value of the first capacitor S112, the inductance value of the second inductor S113, and the capacitance value of the third capacitor S114;

[0071] The first resistor S115 , the second capacitor S116 , the second inductor S113 , and the third capacitor S114 are used together to release radio frequency energy from the radio frequency signal input to the bandpass filter synthesis circuit 341 , so as to protect the bandpass filter synthesis circuit 341 .

[0072] One end of the first inductor S111 is connected to the power amplifier module 200, and the other end is connected to the first capacitor S112. The other end of the first capacitor S112 is grounded. The first inductor S111 and the first capacitor S112 form an inductor-capacitor low-pass filter; the second inductor S113 and the third capacitor S114 are connected in parallel, and one end of the second inductor S113 is connected between the first inductor S111 and the first capacitor S112. The first inductor S111, the first capacitor S112, the second inductor S113 and the third capacitor S114 are connected to perform band-pass filtering; the first inductor S111, the first capacitor S112, the second inductor S113 and the third capacitor S114 are jointly used to select the radio frequency signal corresponding to the target frequency or the radio frequency signal corresponding to the target frequency after filtering out each harmonic. The first resistor S115, the second capacitor S116, the second inductor S113, and the third capacitor S114 are connected in series to ground to release RF energy from the RF signal of the bandpass filter synthesis circuit 341 to protect the bandpass filter synthesis circuit 341. The target frequency of the bandpass filter synthesis circuit 341 can be determined by adjusting the inductance value of the first inductor S111, the capacitance value of the first capacitor S112, the inductance value of the second inductor S113, and the capacitance value of the third capacitor S114 in the circuit.

[0073] Furthermore, in order to enhance the bandpass filtering depth of the bandpass filtering synthesis circuit 341, the bandpass filtering synthesis circuit 341 may further include:

[0074] A fourth capacitor S117 has one end connected to the other end of the first inductor S111, one end of the first capacitor S112, one end of the second inductor S113, and one end of the third capacitor S114, and the other end connected to the low-pass filtering unit, and is used to buffer RF energy in the first inductor S111, the first capacitor S112, the second inductor S113, and the third capacitor S114.

[0075] The fourth capacitor S117 is a resonant capacitor, which is connected to the first inductor S111, the first capacitor S112, the second inductor S113, and the third capacitor S114 to buffer the energy in the first inductor S111, the first capacitor S112, the second inductor S113, and the third capacitor S114, thereby enhancing the bandpass filtering effect of the bandpass filter synthesis circuit.

[0076] In an optional embodiment of the present invention, the low-pass filter synthesis unit 350 includes at least one resistor-capacitor filter circuit 351. The number of the resistor-capacitor filter circuits 351 matches the number of the band-pass filter synthesis units 340. The resistor-capacitor filter circuits include:

[0077] A second resistor S211, one end of which is connected to the bandpass filter synthesis unit 340, and the other end of which is connected to the synthesis output filter unit 330;

[0078] The fifth capacitor S212 has one end connected to the other end of the second resistor S211 and the synthesis output filtering synthesis unit, and the other end grounded.

[0079] In an embodiment of the present invention, the low-pass filter synthesis unit 350 includes at least two resistor-capacitor filter circuits; the number of the resistor-capacitor filter circuits matches the number of the band-pass filter synthesis units 340; the band-pass filter synthesis unit 340 is connected to a corresponding resistor-capacitor filter circuit 351, and the corresponding resistor-capacitor filter circuit 351 performs low-pass filtering. For example, the number of the resistor-capacitor filter circuits is the same as the number of the band-pass filter synthesis units 340, and the number of the resistor-capacitor filter circuits and the number of the band-pass filter synthesis units 340 are 1:1. Each resistor-capacitor filter circuit 351 performs low-pass filtering for the only band-pass filter synthesis unit 340 connected thereto. Each resistor-capacitor filter circuit has the same structure. Each resistor-capacitor filter circuit 351 includes a second resistor S211 and a fifth capacitor S212. One end of the second resistor S211 is connected to the bandpass filter synthesis unit 340, and the other end is connected to the synthesis output filter unit 330; one end of the fifth capacitor S212 is connected to the other end of the second resistor S211 and the synthesis output filter synthesis unit, and the other end is grounded; the second resistor S211 and the fifth capacitor S212 form a low-pass filter circuit, which filters out the harmonics of the radio frequency signal corresponding to the target frequency, or filters out the harmonics in the radio frequency signal. In actual applications, the fifth capacitor S212 can be a single capacitor or a capacitor group composed of multiple capacitors of different capacitance values connected in parallel to filter out harmonic components of different frequencies.

[0080] Furthermore, the synthesis output filter unit 330 includes: a symmetrical network circuit connected to the second filter synthesis unit 320, and used to compensate for the radio frequency power output by the second filter synthesis unit when the resistance is not 50Ω.

[0081] In practical applications, a symmetrical network circuit can be connected to the low-pass filter synthesis unit 350. Leveraging the symmetry of the symmetrical network circuit, the symmetrical network circuit can effectively compensate for the RF power output under high standing waves, regardless of changes in load conditions, thereby minimizing the impact of reflected waves and ensuring the stability of the RF power supply output power. Specific types of symmetrical network circuits include, but are not limited to, symmetrical LC filter circuits, symmetrical RC filter circuits, symmetrical π-type LC filter circuits, and symmetrical active filter circuits. In one example of the present invention, the symmetrical network circuit can be a symmetrical π-type LC filter circuit, i.e., a centrosymmetric π-network circuit.

[0082] Specifically, the symmetrical network circuit includes:

[0083] A third inductor S32, one end of which is connected to the low-pass filter synthesis module and the other end of which is output;

[0084] a sixth capacitor S31, one end of which is connected to one end of the third inductor S32, and the other end of which is grounded;

[0085] a seventh capacitor S33, one end of which is connected to the other end of the third inductor S33, and the other end of which is grounded;

[0086] The third inductor S32, the sixth capacitor S31, and the seventh capacitor S33 act together on the RF signal output by the second filtering and synthesizing unit 320;

[0087] The third inductor S32 is a resonant inductor, the sixth capacitor S31 and the seventh capacitor S33 are ground capacitors, and the third inductor S32, the sixth capacitor S31 and the seventh capacitor S33 are connected to form a symmetrical network circuit.

[0088] The symmetry of the symmetrical network circuit is used to compensate for the power output, which minimizes the impact of the reflected wave and improves the output power stability of the power supply under high standing waves and frequent changes in the chamber impedance. The actual test results are as follows: Figure 6 As shown, under different impedance points with high standing waves, the power output of the RF power supply using this filtering method is similar to the ideal output power stability, with no noticeable power jumps. In practical applications, when the chamber exhibits high standing waves, the RF power supply can maintain relatively stable power output, the adaptability of the same power supply to different chambers is enhanced, and the sensitivity to cable length is significantly reduced.

[0089] In one embodiment of the present invention, the first inductor S111, the second inductor S113, and the third inductor S32 can be implemented using microstrip lines. This effectively reduces the space occupied by the synthesis module, facilitating miniaturization of the overall structure of the RF power supply.

[0090] In addition, the bandpass filter synthesis unit 340, the low-pass filter synthesis unit 350 and the bandpass filter synthesis unit 340 can use ceramic substrates as circuit substrates, which significantly improves the heat dissipation of the entire circuit and solves the problem of heat dissipation difficulty of the synthesis circuit.

[0091] In summary, when using the RF power supply described in the embodiments of the present invention for etching, the matching time between the RF power supply and the chamber is significantly shortened due to the more stable power output during the matching process. This increases the effective process time and significantly improves the etching rate. The multiple filtering results in a more stable power output, which in turn stabilizes the plasma state during the etching process, promoting etching uniformity.

[0092] Reference Figure 7 , showing that an embodiment of the present invention further discloses a semiconductor process equipment, the semiconductor process equipment comprising an RF power supply, an RF matching device, and a process chamber. The RF power supply is the RF power supply described above, and the RF power supply is used to output RF power to the electrodes of the process chamber. The RF matching device is used to load the RF power into the process chamber to excite the process gas in the process chamber to form plasma. The process chamber is used to process a wafer to be processed based on the plasma. The RF power supply is the RF power supply in the embodiment described above.

[0093] The process chamber 710 further includes a cathode (metal target) submodule 711 and an anode (sputtered material) submodule 712. The positive electrode of the RF power supply 720 is grounded through the RF matcher 730 and connected to the anode (sputtered material) submodule 712 of the plasma chamber 710, while the negative electrode of the RF power supply 720 is connected to the cathode (metal target) submodule 711 of the plasma chamber 710. After the positive and negative electrodes of the RF power supply 720 are connected to the plasma chamber submodule 710, RF power is used to generate plasma. The generated plasma rushes toward the cathode (metal target) submodule 711. The metal atoms in the cathode (metal target) submodule 711 are sputtered out and attached to the anode (sputtered material) submodule 712, completing the thin film deposition on the anode (sputtered material).

[0094] When the process requires increased RF power, the power amplifier module in the RF power supply 720 can output multiple RF powers at the same time, and the RF power synthesis device in the RF power supply 720 synthesizes the multiple RF powers and outputs a synthesized RF power to the process chamber.

[0095] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only 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 terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or terminal device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or terminal device that includes the element.

[0096] The above is a detailed introduction to the RF power supply and semiconductor process equipment provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method and core idea of the present invention. At the same time, for those skilled in the art, according to the idea of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. A radio frequency power supply, characterized in that: include: The driver module, power amplifier module and filter module are connected in sequence; The driving module is used to output a driving signal, and the power amplifier module is used to output a radio frequency signal under the stimulation of the driving signal; The filtering module includes: a first filtering and synthesizing unit, whose input end is connected to the output end of the power amplifier module and is used to filter out interference signals in the radio frequency signal; a second filtering and synthesizing unit, whose input end is connected to the output end of the first filtering and synthesizing unit, and is used to perform secondary filtering on the radio frequency signal output by the first filtering and synthesizing unit; The synthesis output filter unit has an input end connected to the output end of the second filtering synthesis unit and is used to compensate for the radio frequency power output by the second filtering synthesis unit.

2. The radio frequency power supply according to claim 1, characterized in that The first filter synthesis unit is a bandpass filter synthesis unit, whose input end is connected to the output end of the power amplifier module, and is used to select the radio frequency signal corresponding to the target frequency; the second filter synthesis unit is a low-pass filter synthesis unit, whose input end is connected to the output end of the bandpass filter synthesis unit, and is used to filter out the harmonics of the radio frequency signal corresponding to the target frequency; or The first filtering synthesis unit is a low-pass filtering synthesis unit, whose input end is connected to the output end of the power amplifier module, and is used to filter out the harmonics in the radio frequency signal; the second filtering synthesis unit is a band-pass filtering synthesis unit, whose input end is connected to the output end of the low-pass filtering synthesis unit, and is used to select the radio frequency signal corresponding to the target frequency after filtering out the harmonics.

3. The radio frequency power supply according to claim 2, characterized in that: The bandpass filter synthesis unit includes at least one bandpass filter synthesis circuit. The number of the bandpass filter synthesis circuits matches that of the power amplifier modules and the bandpass filter synthesis circuits are connected to the output ends of the corresponding power amplifier modules.

4. The radio frequency power supply according to claim 3, characterized in that: The bandpass filtering synthesis circuit comprises: a first inductor, one end of which is connected to the power amplifier module; a first capacitor, one end of which is connected to the other end of the first inductor and the other end of which is grounded; a second inductor, one end of which is connected between the first inductor and the first capacitor; a first resistor, one end of which is connected to the other end of the second inductor; a second capacitor, one end of which is connected to the other end of the first resistor and the other end of which is grounded; a third capacitor connected in parallel across the second inductor; The first inductor, the first capacitor, the second inductor, and the third capacitor are used together to select a radio frequency signal corresponding to a target frequency or to select a radio frequency signal corresponding to the target frequency after filtering out harmonics, wherein the target frequency is determined by the inductance value of the first inductor, the capacitance value of the first capacitor, the inductance value of the second inductor, and the capacitance value of the third capacitor; The first resistor, the second capacitor, the second inductor and the third capacitor are used together to release radio frequency energy of the radio frequency signal input to the bandpass filter synthesis circuit to protect the bandpass filter synthesis circuit.

5. The radio frequency power supply according to claim 4, characterized in that: The bandpass filtering synthesis circuit further includes: a fourth capacitor, one end of which is connected to the other end of the first inductor, one end of the first capacitor, one end of the second inductor, and one end of the third capacitor, and the other end of which is connected to the low-pass filtering unit, for buffering RF energy in the first inductor, the first capacitor, the second inductor, and the third capacitor.

6. The radio frequency power supply according to claim 4, characterized in that: The first inductor and the second inductor are microstrip line inductors.

7. The radio frequency power supply according to claim 2, characterized in that: The low-pass filter synthesis module includes at least one resistor-capacitor filter circuit, the number of which matches the number of the band-pass filter synthesis units, and the resistor-capacitor filter circuit includes: a second resistor, one end of which is connected to the bandpass filter synthesis unit, and the other end of which is connected to the synthesis output filter unit; a fifth capacitor, one end of which is connected to the other end of the second resistor and the synthesis output filter unit, and the other end of which is grounded; The second resistor and the fifth capacitor are used together to filter out the harmonics of the radio frequency signal corresponding to the target frequency, or to filter out the harmonics in the radio frequency signal.

8. The radio frequency power supply according to claim 2, characterized in that: The synthesis output filtering unit comprises: A symmetrical network circuit is connected to the second filtering and synthesizing unit and is used to compensate for the radio frequency power output by the second filtering and synthesizing unit.

9. The radio frequency power supply according to claim 8, characterized in that: The symmetrical network circuit includes: A third inductor, one end of which is connected to the low-pass filter synthesis module and the other end of which is output; a sixth capacitor, one end of which is connected to one end of the third inductor and the other end of which is grounded; a seventh capacitor, one end of which is connected to the other end of the third inductor and the other end of which is grounded; The third inductor and the sixth capacitor are used together to compensate for the radio frequency power output by the second filtering and combining unit; The third inductor, the sixth capacitor and the seventh capacitor are used together to compensate for the radio frequency power output by the second filtering and combining unit.

10. A semiconductor process equipment, characterized in that: The semiconductor process equipment includes a radio frequency power supply, a radio frequency matching device, and a process chamber, wherein the radio frequency power supply is the radio frequency power supply according to any one of claims 1 to 9, and the radio frequency power supply is used to provide the radio frequency power to the process chamber through the radio frequency matching device to excite the process gas in the process chamber to form plasma; The process chamber is used for processing a wafer to be processed based on the plasma.

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