A radio frequency plasma matching network circuit

Abstract

The present application provides a radio frequency plasma matching network circuit, comprising: a first vacuum relay and a high / low power plasma load matching network. The first vacuum relay is used to achieve switching between the high power plasma load matching network and the low power plasma load matching network. The low power plasma load matching network includes a capacitor module and a resistor module. That is, the capacitor module and the resistor module in the low power plasma load matching network achieve power attenuation of the radio frequency power supply and realize a stable low power plasma process. Specifically, the low power plasma process can be precisely adjusted by adjusting the capacitance of the capacitor module and the resistance of the resistor module. Therefore, the radio frequency plasma matching network circuit provided in the embodiment of the present application can meet the requirements for a high and low energy plasma combination process, expand the process window of semiconductor equipment, and enable better manufacturing of semiconductor devices and chips.

Description

Technical Field

[0001] The present invention relates to the field of semiconductors, and in particular to a radio frequency plasma matching network circuit. Background Art

[0002] With the development of semiconductor-related technologies, the manufacturing process of semiconductor devices and chips is also developing rapidly. In the manufacturing process of semiconductor devices and chips, a variety of semiconductor equipment is required, such as equipment including radio frequency plasma modules.

[0003] In some semiconductor device and chip manufacturing processes, there's a need for a combination of high and low plasma energies, with a power ratio difference of 30 dB (dB) and a low energy output of less than 1 watt. However, while high-energy or high-power plasma output is easier to achieve and more stable for RF power supplies, low-energy or low-power plasma stabilization processes often lack the precision and stability required.

[0004] Therefore, the urgent problem to be solved now is how to achieve the accuracy and stability of the high and low power plasma combination process of the RF power supply. Summary of the Invention

[0005] In view of this, the purpose of the present application is to provide a radio frequency plasma matching network circuit that can achieve accurate and stable output of a high and low power plasma combination of a radio frequency power supply.

[0006] An embodiment of the present application provides a radio frequency plasma matching network circuit, the circuit comprising: a first vacuum relay, a high power plasma load matching network or a low power plasma load matching network;

[0007] The high-power plasma load matching network includes a first fixed vacuum capacitor, and the low-power plasma load matching network includes a capacitor module and a resistor module;

[0008] The input end of the first vacuum relay is connected to a radio frequency power supply, the output end of the first vacuum relay is connected to an input end of a high-power plasma load matching network or an input end of a low-power plasma load matching network, and the input end of the first vacuum relay is connected to the capacitor module;

[0009] The output end of the high-power plasma load matching network or the output end of the low-power plasma load matching network is connected to a radio frequency plasma load, and the resistance module is connected to the radio frequency plasma load.

[0010] Optionally, the resistance module includes a parallel resistance module and a series resistance module, the output end of the series resistance module is connected to the RF plasma load, the input end of the series resistance module is connected to the output end of the capacitor module, and the parallel resistance module and the series resistance module are connected in parallel.

[0011] Optionally, the output end of the series resistance module is connected to the input end of the parallel resistance module, and the output end of the parallel resistance module is grounded.

[0012] Optionally, the circuit includes a second vacuum relay;

[0013] The output end of the second vacuum relay is connected to the radio frequency plasma load, and the input end of the second vacuum relay is connected to the output end of the series resistance module and the output end of the high power plasma load matching network.

[0014] Optionally, the input end of the series resistance module is connected to the input end of the parallel resistance module, and the output end of the parallel resistance module is grounded.

[0015] Optionally, the circuit includes a second vacuum relay;

[0016] The output end of the second vacuum relay is connected to the radio frequency plasma load, and the input end of the second vacuum relay is connected to the output end of the series resistance module and the output end of the high power plasma load matching network.

[0017] Optionally, a ratio of the resistance value of the series resistance module to the resistance value of the RF plasma load is greater than a target threshold value, and the target threshold value is at least greater than 10.

[0018] Optionally, the target threshold is at least greater than 20.

[0019] Optionally, the output power of the RF power supply has a corresponding relationship with the voltage of the RF plasma load using the high-power plasma load matching network or the low-power plasma load matching network.

[0020] Optionally, the corresponding relationship is a linear relationship.

[0021] Optionally, the resistance value of the resistance module is adjusted to adjust the current value of the RF plasma load.

[0022] Optionally, the capacitance value of the capacitor module is adjusted to adjust the voltage value of the RF plasma load.

[0023] Optionally, the series resistance module and the parallel resistance module include resistors with adjustable resistance values.

[0024] Optionally, the series resistance module includes one or more resistors, and the parallel resistance module includes one or more resistors.

[0025] Optionally, the capacitor module includes a second fixed vacuum capacitor and a third fixed vacuum capacitor, the input end of the second fixed vacuum capacitor is connected to the output end of the first vacuum relay, the output end of the second fixed vacuum capacitor is connected to the input end of the third fixed vacuum capacitor, and the output end of the third fixed vacuum capacitor is grounded.

[0026] Optionally, the capacitance of the third fixed vacuum capacitor is adjusted to adjust the voltage of the RF plasma load.

[0027] Optionally, the circuit includes a fourth fixed vacuum capacitor and an inductor, the RF power supply is connected to the input end of the inductor, the output end of the inductor is connected to the input end of the first vacuum relay, the input end of the fourth fixed vacuum capacitor is connected to the input end of the inductor, and the output end of the fourth fixed vacuum capacitor is grounded.

[0028] Optionally, a voltage value of the RF plasma load obtained through the high-power plasma load matching network is greater than a voltage value of the RF plasma load obtained through the low-power plasma load matching network.

[0029] Optionally, the output power of the radio frequency power supply is within a target power range, and the target power range is 1-500 watts.

[0030] Optionally, the output power of the radio frequency power supply is less than 30 watts.

[0031] The embodiment of the present application provides a radio frequency plasma matching network circuit, which includes: a first vacuum relay, a high power plasma load matching network or a low power plasma load matching network, wherein the input end of the first vacuum relay is connected to the radio frequency power supply, the output end of the first vacuum relay is connected to the input end of the high power plasma load matching network or the input end of the low power plasma load matching network, and the output end of the high power plasma load matching network or the output end of the low power plasma load matching network is connected to the radio frequency plasma load, that is, the first vacuum relay is used to realize switching between the high power plasma load matching network or the low power plasma load matching network, and the high power plasma load matching network includes a first solid state relay. A fixed vacuum capacitor, a low-power plasma load matching network includes a capacitor module and a resistor module, the input end of the first vacuum relay is connected to the capacitor module, and the resistor module is connected to the RF plasma load, that is, the capacitor module and the resistor module in the low-power plasma load matching network realize power attenuation of the RF power supply, and realize a stable process of low-power plasma. Specifically, the capacitance of the capacitor module and the resistance of the resistor module can be adjusted to achieve precise adjustment of the low-power plasma process. It can be seen that the RF plasma matching network circuit provided in the embodiment of the present application can meet the needs of high and low energy plasma combination processes, expand the process window of semiconductor equipment, and better carry out the manufacture of semiconductor devices and chips. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0033] Figure 1 A schematic structural diagram of a radio frequency plasma matching network circuit provided in an embodiment of the present application is shown;

[0034] Figure 2 A schematic diagram showing the corresponding relationship between the output power of a radio frequency power supply provided in an embodiment of the present application and the energy obtained by a radio frequency plasma load is shown;

[0035] Figure 3 A schematic structural diagram of another radio frequency plasma matching network circuit provided in an embodiment of the present application is shown;

[0036] Figure 4 A schematic structural diagram of another radio frequency plasma matching network circuit provided in an embodiment of the present application is shown;

[0037] Figure 5A schematic structural diagram of another radio frequency plasma matching network circuit provided in an embodiment of the present application is shown;

[0038] Figure 6 A schematic structural diagram of another radio frequency plasma matching network circuit provided in an embodiment of the present application is shown;

[0039] Figure 7 A schematic structural diagram of another radio frequency plasma matching network circuit provided in an embodiment of the present application is shown;

[0040] Figure 8 A schematic structural diagram of another radio frequency plasma matching network circuit provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0041] In order to help those skilled in the art better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of this application.

[0042] In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0043] This application is described in detail with reference to schematic diagrams. When describing the embodiments of this application, for ease of explanation, cross-sectional views of device structures may be partially enlarged and not to scale. Furthermore, these schematic diagrams are merely illustrative and should not limit the scope of protection of this application. Furthermore, in actual production, three-dimensional dimensions, including length, width, and depth, should be included.

[0044] With the development of semiconductor-related technologies, the manufacturing process of semiconductor devices and chips is also developing rapidly. In the manufacturing process of semiconductor devices and chips, a variety of semiconductor equipment is required, such as equipment including radio frequency plasma modules.

[0045] In some semiconductor device and chip manufacturing processes, there's a need for a combination of high and low plasma energies, with a power ratio difference of 30 dB and a low energy of less than 1 watt. However, for RF power supplies, high-energy or high-power plasma processes are easier to implement and offer greater stability, but low-energy or low-power plasma processes often lack the precision and stability required.

[0046] There are currently two plasma output solutions for a wide power range:

[0047] The first approach involves a wide-range RF power supply solution. However, current RF power supplies are limited by power amplifier chip technology (30dB). Common RF power supplies for low-temperature plasmas driven at 13.56 MHz typically have effective output powers ranging from a few watts (or even tens of watts) to several kilowatts. For practical applications combining high and low energies, high-power output is easier to achieve and offers greater stability. Although some RF power supplies have developed high-accuracy low-output (HALO) capabilities, it is difficult to meet extreme output and accuracy requirements for outputs of 1 watt or even lower. Furthermore, the low-temperature RF plasma drive module includes the RF power supply, transmission cable, matching network, and plasma confinement vessel. RF energy is dissipated in various forms from the moment it is generated. While theoretically achieving consistency between the source impedance, cable characteristic impedance, and the impedance of the matching network after conjugation with the plasma in the RF circuit, some nonlinear power losses still exist within these modules. For some high-power plasma applications, the impact of these nonlinear losses is not significant. However, for low-power plasma applications, they are unacceptable, as they directly impact the stability and repeatability of process results. For example, some common RF plasma matching networks have a set power input threshold, such as greater than 20.0Watt. In this case, application requirements of 1.0Watt or even lower power cannot be met.

[0048] The second approach involves attenuating the RF power supply output. This approach directly restricts the RF power supply's output power range, reduces semiconductor equipment efficiency, and increases equipment rack, heat dissipation, and maintenance costs. Furthermore, this approach places the power attenuation module at the front end of the matching network, which also presents stability issues with low-power plasma, making it difficult to guarantee process repeatability and other indicators.

[0049] Therefore, the urgent problem to be solved now is how to achieve the accuracy and stability of the high and low power plasma combination process of the RF power supply.

[0050] Based on this, an embodiment of the present application provides a radio frequency plasma matching network circuit, which includes: a first vacuum relay, a high-power plasma load matching network, and a low-power plasma load matching network. The input end of the first vacuum relay is connected to the radio frequency power supply and the front-end matching network, the output end of the first vacuum relay is connected to the input end of the high-power plasma load matching network or the input end of the low-power plasma load matching network, and the output end of the high-power plasma load matching network or the output end of the low-power plasma load matching network is connected to the radio frequency plasma load. That is, the first vacuum relay is used to realize switching between the high-power plasma load matching network and the low-power plasma load matching network. The high-power plasma load matching network It includes a first fixed vacuum capacitor, and the low-power plasma load matching network includes a capacitor module and a resistor module. The input end of the first vacuum relay is connected to the capacitor module, and the resistor module is connected to the RF plasma load. That is to say, the capacitor module and the resistor module in the low-power plasma load matching network realize power attenuation of the RF power supply and realize a stable process of low-power plasma. Specifically, the capacitance of the capacitor module and the resistance of the resistor module can be adjusted to achieve precise adjustment of the low-power plasma process. It can be seen that the RF plasma matching network circuit provided in the embodiment of the present application can meet the needs of high- and low-energy plasma combination processes, expand the process window of semiconductor equipment, and better carry out the manufacture of semiconductor devices and chips.

[0051] In order to better understand the technical solutions and technical effects of the present application, specific embodiments will be described in detail below with reference to the accompanying drawings.

[0052] See also Figure 1 , which is a structural schematic diagram of a radio frequency plasma matching network circuit provided in an embodiment of the present application.

[0053] The radio frequency plasma matching network circuit 100 provided in this embodiment includes: a first vacuum relay 110 , a high-power plasma load matching network 200 , and a low-power plasma load matching network 300 .

[0054] In the embodiment of the present application, the RF plasma matching network circuit 100 is disposed between the RF power supply 10 and the RF plasma load 20 , and is used to process the output power of the RF power supply 10 and then input it to the RF plasma load 20 .

[0055] The RF plasma matching network circuit 100 includes a high-power plasma load matching network 200 and a low-power plasma load matching network 300. That is, the high-power plasma load matching network 200 can be used to output high power to the RF plasma load 20, and the low-power plasma load matching network 300 can be used to output low power to the RF plasma load 20, thereby realizing high and low energy combined loading for the RF plasma load 20 and expanding the plasma load power range.

[0056] refer to Figure 1 As shown, the input end of the first vacuum relay 110 is connected to the RF power supply 10, the output end of the first vacuum relay 110 is connected to the input end of the high-power plasma load matching network 200 or the input end of the low-power plasma load matching network 300, and the output end of the high-power plasma load matching network 200 or the output end of the low-power plasma load matching network 300 is connected to the RF plasma load 20. In other words, the first vacuum relay 110 can be used to implement switching between the high-power plasma load matching network 200 and the low-power plasma load matching network 300.

[0057] The high power plasma load matching network 200 includes a first fixed vacuum capacitor 210 . That is, the first fixed vacuum capacitor 210 can be used to implement a high power plasma stabilization process.

[0058] The low-power plasma load matching network 300 includes a capacitor module 310 and a resistor module 320. The input end of the first vacuum relay 110 is connected to the capacitor module 310, which is then connected to the resistor module 320. The resistor module 320 is then connected to the RF plasma load 20. In other words, the current of the RF power source 10 first flows through the capacitor module 310 and then flows through the resistor module 320 to the RF plasma load 20. Thus, the low-power plasma load matching network 300 can be used to attenuate the output power of the RF power source 10, thereby achieving a stable low-power plasma process.

[0059] Thus, the RF plasma matching network circuit provided by the embodiments of the present application, including a high-power plasma load matching network and a low-power plasma load matching network, can meet the needs of high- and low-energy plasma combined processes, expand the process window of semiconductor equipment, and better enable the manufacture of semiconductor devices and chips. Furthermore, the low-power plasma load matching network, a module capable of achieving power attenuation, is incorporated into the matching network to achieve stability in low-power plasma processes and ensure repeatable process results. Furthermore, because the matching network regulates the high and low powers of the plasma load, the output power of the RF power supply can be kept constant, greatly improving the stability of the low output power.

[0060] In practical applications, the output power of the RF power supply 10 can be fixed and remain within a target power range, which can be 1-500 watts. That is, the RF plasma matching network circuit 100 of the present application can be used to arbitrarily adjust the output power of the same RF power supply 10 to meet the wide dynamic power range requirements of the RF plasma load 20. There is no need for the output power of the RF power supply 10 to have high and low thresholds, that is, there is no output power regulation for the RF power supply 10 itself.

[0061] In the embodiment of the present application, when the power input to the RF plasma load 20 is adjusted using the high-power plasma load matching network 200 or the low-power plasma load matching network 300 , the output power of the RF power supply 10 and the energy obtained by the RF plasma load 20 have a corresponding relationship.

[0062] Specifically, the energy obtained by the RF plasma load 20 can be reflected by voltage. That is, there is a corresponding relationship between the output power of the RF power supply 10 and the voltage obtained by the RF plasma load 20 .

[0063] Refer to Table 1, which shows the output power of the RF power supply 10 and the energy obtained by the RF plasma load 20 under different RF plasma matching network circuits 100. Among them, RF power is the output power of the RF power supply 10, and the energy obtained by the plasma load under different matching networks is expressed by the voltage peak value (Vpeak-peak).

[0064] Table 1

[0065]

[0066] refer to Figure 2 As shown, by reflecting the data described in the above table using a graph, it can be seen that, whether passing through the high-power plasma load matching network 200 or the low-power plasma load matching network 300, the output power of the RF power supply 10 and the voltage obtained by the RF plasma load 20 are in a linear relationship.

[0067] Refer to Table 1 and Figure 2 As shown, the energy outputted by the high-power plasma load matching network 200 is greater than the energy outputted by the low-power plasma load matching network 300. In other words, the voltage value of the RF plasma load 20 obtained by the high-power plasma load matching network 200 is greater than the voltage value of the RF plasma load 20 obtained by the low-power plasma load matching network 300.

[0068] It can be seen that, without affecting the impedance and output power of the RF power supply 10 , the power entering the RF plasma load 20 can be enhanced by using the high-power plasma load matching network 300 , and the voltage value of the RF plasma load 20 can be increased by increasing the capacitance value of the capacitor module 310 .

[0069] Accordingly, the low-power plasma load matching network 300 can be used to attenuate the power entering the RF plasma load 20, and the voltage value of the RF plasma load 20 can be adjusted by adjusting the capacitance value of the capacitor module 310, and the current value of the RF plasma load 20 can be adjusted by adjusting the resistance value of the resistor module 320, thereby achieving precise adjustment for the low-power plasma stabilization process.

[0070] As an example, the voltage of the RF plasma load 20 is reduced by reducing the capacitance of the capacitor module 310 , and the current of the RF plasma load 20 is reduced by increasing the resistance of the resistor module 320 .

[0071] In the examples of this application, reference is made to Figure 3 As shown, the capacitor module 310 includes a second fixed vacuum capacitor 311 and a third fixed vacuum capacitor 312. The input end of the second fixed vacuum capacitor 311 is connected to the output end of the first vacuum relay 110, the output end of the second fixed vacuum capacitor 311 is connected to the input end of the third fixed vacuum capacitor 312, and the output end of the third fixed vacuum capacitor 312 is grounded. In other words, the current of the RF power supply 10 first flows through the second fixed vacuum capacitor 311 and then flows through the third fixed vacuum capacitor 312. That is, the second fixed vacuum capacitor 311 is a series capacitor, and the third fixed vacuum capacitor 312 is a parallel capacitor.

[0072] In an embodiment of the present application, the resistance module 320 includes a parallel resistance module 321 and a series resistance module 322, wherein the output end of the series resistance module 322 is connected to the RF plasma load 20, and the input end of the series resistance module 322 is connected to the output end of the capacitor module 310. That is, the current of the RF power supply 10 flows through the series resistance module 322 and then flows into the RF plasma load 20.

[0073] The parallel resistance module 321 and the series resistance module 322 are connected in parallel. The current of the RF power supply 10 flows through the parallel resistance module 321 and then is grounded through the parallel resistance module 321 .

[0074] That is, the resistance module 320 uses the parallel resistance module 321 and the series resistance module 322 to adjust the overall resistance, thereby adjusting the current value of the RF plasma load 20 .

[0075] In an embodiment of the present application, when the parallel resistance module 321 and the series resistance module 322 are connected in parallel, the series-parallel connection order of the parallel resistance module 321 and the series resistance module 322 can be adjusted according to actual conditions to improve the power output stability of the low-power plasma load matching network 300.

[0076] As a possible implementation, the output end of the series resistor module 322 is connected to the input end of the parallel resistor module 321, and the output end of the parallel resistor module 321 is grounded. That is, the current of the RF power supply 10 first flows through the series resistor module 322 and then flows through the parallel resistor module 321 to ground. Figure 4 As shown, the input end of the parallel resistance module 321 is closer to the RF plasma load 20 .

[0077] In practical applications, when the first vacuum relay 110 is connected to the high-power plasma load matching network 300, in addition to the RF plasma load 20, there is also a load of the resistance module 320 in the low-power plasma load matching network 300. In order to avoid the load effect of the resistance module 320, a second vacuum relay 120 can be provided between the input end of the parallel resistance module 321 and the RF plasma load 20. Figure 4 As shown, the second vacuum relay 120 and the first vacuum relay 110 are used to implement switching between high and low power plasma load matching networks.

[0078] Specifically, the output end of the second vacuum relay 120 is connected to the RF plasma load 20, and the input end of the second vacuum relay 120 is connected to the output end of the series resistor module 322 and the output end of the high-power plasma load matching network 200. When the second vacuum relay 120 and the first vacuum relay 110 are simultaneously connected to the high-power plasma load matching network 200, the high-power plasma load matching network 200 is used to provide energy to the RF plasma load 20. At this time, the RF plasma load 20 is not connected to the low-power plasma load matching network 300, eliminating the load effect of the resistor module 320 in the low-power plasma load matching network 300. In other words, using two vacuum relays to adjust the high- and low-power plasma load matching networks can improve the stability of the output power.

[0079] As another possible implementation, the input end of the series resistor module 322 is connected to the input end of the parallel resistor module 321, and the output end of the parallel resistor module 321 is grounded. That is, the series and parallel connection order between the series resistor module 322 and the parallel resistor module 321 is first the parallel resistor module 321 and then the series resistor module 322. Figure 5 or Figure 6As shown, a series resistance module 322 is provided between the input end of the parallel resistance module 321 and the RF plasma load 20 .

[0080] In practical applications, when the first vacuum relay 110 is connected to the high-power plasma load matching network 300, in addition to the RF plasma load 20, there is also a load of the resistor module 320 in the low-power plasma load matching network 300. To avoid the load effect of the resistor module 320, the following two methods can be used:

[0081] A first possible implementation is to set a second vacuum relay 120 between the output end of the series resistance module 322 and the RF plasma load 20. Figure 5 As shown, the second vacuum relay 120 and the first vacuum relay 110 are used to implement switching between high and low power plasma load matching networks.

[0082] Specifically, the output end of the second vacuum relay 120 is connected to the RF plasma load 20, and the input end of the second vacuum relay 120 is connected to the output end of the series resistor module 322 and the output end of the high-power plasma load matching network 200. When the second vacuum relay 120 and the first vacuum relay 110 are simultaneously connected to the high-power plasma load matching network 200, the high-power plasma load matching network 200 is used to provide energy to the RF plasma load 20. At this time, the RF plasma load 20 and the low-power plasma load matching network 300 are not connected, thereby eliminating the load effect of the resistor module 320 in the low-power plasma load matching network 300. In other words, using two vacuum relays to switch between the high-power and low-power plasma load matching networks can improve the stability of the output power.

[0083] A second possible implementation is to set the resistance value of the series resistance module 322 to be much larger than the resistance value of the RF plasma load 20, thereby eliminating the load effect of the resistance module 320. Figure 6 As shown, the second vacuum relay 120 may not be additionally provided at this time, and a single relay, namely the first vacuum relay 110 , may be used to control the adjustment of high and low output powers, thereby reducing the manufacturing cost of the RF plasma matching network circuit 100 .

[0084] Specifically, the ratio of the resistance value of the series resistance module 322 to the resistance value of the RF plasma load 20 is greater than a target threshold value, and the target threshold value is at least greater than 10. Furthermore, the target threshold value is at least greater than 20.

[0085] As an example, if the resistance value |Z| of the RF plasma load 20 is less than 15 ohms, to eliminate the load effect of the resistance module 320, the resistance value R_seri of the series resistance module 322 is at least greater than 10×|Z|. For example, if R_seri = 200 ohms, the RF plasma load 20 is not affected by the low-power plasma load matching network.

[0086] In actual applications, the resistance value of the series resistor module 322 may be relatively large, and the parallel resistor module 321 can be used to adjust the overall resistance value of the resistor module 320. That is, the resistance value of the parallel resistor module 321 is used to reduce the resistance value of the low-power plasma matching network 200 to an ideal working range. In this way, it is possible to use a single relay to control the high- and low-power plasma load matching networks and eliminate the load effect.

[0087] In the embodiment of the present application, the series resistance module 322 and the parallel resistance module 321 can each include one or more resistors. That is, the series resistance module 322 can be composed of a single resistor or a plurality of resistors connected in parallel or in series. Correspondingly, the parallel resistance module 321 can also be composed of a single resistor or a plurality of resistors connected in parallel or in series.

[0088] In actual applications, the series resistance module 322 and the parallel resistance module 321 also include resistors with adjustable resistance values. That is to say, the resistors in the series resistance module 322 and the parallel resistance module 321 can not only use resistors with fixed resistance values, but also resistors with adjustable resistance values. In this way, any low output power can be achieved, the output range of low output power can be expanded, and the application requirements of different processes can be further met.

[0089] Because the resistance module 320 in the low-power plasma load matching network 300 can affect the energy input to the RF plasma load 20, the energy input to the RF plasma load 20 can be controlled by controlling the resistance value of the resistance module 320. Accordingly, the resistance value of the resistance module 320 can be determined based on the required energy of the RF plasma load 20. Furthermore, when the resistance module 320 includes an adjustable resistor, the energy obtained by the RF plasma load 20 can be controlled in real time by controlling the resistance value of the resistance module 320, thereby achieving dynamic energy control.

[0090] In an embodiment of the present application, other electrical components, such as a fourth fixed vacuum capacitor 130 , a fifth fixed vacuum capacitor 140 , and an inductor 150 , may be further provided between the RF power supply 10 and the first vacuum relay 110 to improve circuit stability.

[0091] As an example, see Figure 7As shown, the RF power supply 10 is connected to the input end of the inductor 150, the output end of the inductor 150 is connected to the input end of the first vacuum relay 110, the input end of the fourth fixed vacuum capacitor 130 is connected to the input end of the inductor 150, and the output end of the fourth fixed vacuum capacitor 130 is grounded. In other words, the fourth fixed vacuum capacitor 130 is connected in parallel, and the inductor 150 is connected in series.

[0092] In practical applications, the output end of the fourth fixed vacuum capacitor 130 may also be connected in series with an inductor, and the inductor is grounded, which can improve circuit stability.

[0093] As another example, see Figure 8 As shown, the RF power supply 10 is connected to the input end of the inductor 150, the output end of the inductor 150 is connected to the input end of the fifth fixed vacuum capacitor 140, the output end of the fifth fixed vacuum capacitor 140 is connected to the input end of the first vacuum relay 110, the input end of the fourth fixed vacuum capacitor 130 is connected to the input end of the inductor 150, and the output end of the fourth fixed vacuum capacitor 130 is grounded. In other words, the fourth fixed vacuum capacitor 130 is connected in parallel, and the inductor 150 and the fifth fixed vacuum capacitor 140 are connected in series.

[0094] It can be seen that the RF plasma matching network circuit 100 provided in the embodiment of the present application can meet the process requirements of high and low energy plasma combinations and extend the available power span of semiconductor equipment. It can achieve the stability requirements of low energy output and reduce the errors caused by nonlinear losses in the circuit. It can switch between high and low output powers without affecting the output power of the RF power supply to meet the application of different processes, expand the controllable range of the lower electrode DC-Bias, and expand the process window of the equipment. In addition, for special plasma process applications, such as low-power plasma processes, the resistance module in the low-power plasma load matching network will compensate for the real impedance to ensure the stability of the process.

[0095] The embodiment of the present application provides a radio frequency plasma matching network circuit, which includes: a first vacuum relay, a high-power plasma load matching network, and a low-power plasma load matching network. The input end of the first vacuum relay is connected to the radio frequency power supply, the output end of the first vacuum relay is connected to the input end of the high-power plasma load matching network or the input end of the low-power plasma load matching network, and the output end of the high-power plasma load matching network or the output end of the low-power plasma load matching network is connected to the radio frequency plasma load. In other words, the first vacuum relay is used to realize switching between the high-power plasma load matching network and the low-power plasma load matching network. The high-power plasma load matching network includes the first vacuum relay. A fixed vacuum capacitor, a low-power plasma load matching network includes a capacitor module and a resistor module, the input end of the first vacuum relay is connected to the capacitor module, and the resistor module is connected to the RF plasma load. That is to say, the capacitor module and the resistor module in the low-power plasma load matching network realize power attenuation of the RF power supply and achieve a stable process of low-power plasma. Specifically, the stable process of low-power plasma can be achieved by adjusting the capacitance of the capacitor module and the resistance of the resistor module. It can be seen that the RF plasma matching network circuit provided in the embodiment of the present application can meet the needs of high- and low-energy plasma combination processes, expand the process window of semiconductor equipment, and better carry out the manufacture of semiconductor devices and chips.

[0096] The circuit embodiments described above are merely illustrative, wherein the units and modules described as separate components may or may not be physically separate. Furthermore, some or all of the units and modules may be selected based on actual needs to achieve the objectives of the present embodiment. Those skilled in the art can understand and implement the present invention without inventive effort.

[0097] The above is only a preferred embodiment of the present application. Although the present application has been disclosed as a preferred embodiment, it is not intended to limit the present application. Any technician familiar with the art can use the above-disclosed methods and technical contents to make many possible changes and modifications to the technical solution of the present application without departing from the scope of the technical solution of the present application, or modify it into an equivalent embodiment with equivalent changes. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of protection of the technical solution of the present application.

Claims

1. A radio frequency plasma matching network circuit, characterized in that: The circuit includes: a first vacuum relay, a high-power plasma load matching network and a low-power plasma load matching network; The high-power plasma load matching network includes a first fixed vacuum capacitor, and the low-power plasma load matching network includes a capacitance module and a resistance module; The input end of the first vacuum relay is connected to a radio frequency power supply, the output end of the first vacuum relay is connected to an input end of a high-power plasma load matching network or an input end of a low-power plasma load matching network, and the input end of the first vacuum relay is connected to the capacitor module; The output end of the high-power plasma load matching network or the output end of the low-power plasma load matching network is connected to a radio frequency plasma load, and the resistance module is connected to the radio frequency plasma load.

2. The circuit according to claim 1, characterized in that The resistance module includes a parallel resistance module and a series resistance module. The output end of the series resistance module is connected to the RF plasma load, the input end of the series resistance module is connected to the output end of the capacitor module, and the parallel resistance module and the series resistance module are connected in parallel.

3. The circuit according to claim 2, characterized in that The output end of the series resistance module is connected to the input end of the parallel resistance module, and the output end of the parallel resistance module is grounded.

4. The circuit according to claim 3, characterized in that The circuit includes a second vacuum relay; The output end of the second vacuum relay is connected to the radio frequency plasma load, and the input end of the second vacuum relay is connected to the output end of the series resistance module and the output end of the high power plasma load matching network.

5. The circuit according to claim 2, characterized in that An input end of the series resistance module is connected to an input end of the parallel resistance module, and an output end of the parallel resistance module is grounded.

6. The circuit according to claim 5, characterized in that The circuit includes a second vacuum relay; The output end of the second vacuum relay is connected to the radio frequency plasma load, and the input end of the second vacuum relay is connected to the output end of the series resistance module and the output end of the high power plasma load matching network.

7. The circuit according to claim 5, characterized in that A ratio of a resistance value of the series resistance module to a resistance value of the radio frequency plasma load is greater than a target threshold value, and the target threshold value is at least greater than 10.

8. The circuit according to claim 7, characterized in that The target threshold is at least greater than 20.

9. The circuit according to claim 1, wherein: The output power of the radio frequency power supply has a corresponding relationship with the voltage of the radio frequency plasma load using the high power plasma load matching network or the low power plasma load matching network.

10. The circuit according to claim 9, characterized in that The corresponding relationship is a linear relationship.

11. The circuit according to claim 9, characterized in that The resistance value of the resistance module is adjusted to adjust the current value of the RF plasma load.

12. The circuit according to claim 9, characterized in that The capacitance value of the capacitor module is adjusted to adjust the voltage value of the RF plasma load.

13. The circuit according to claim 2, characterized in that The series resistance module and the parallel resistance module include resistors with adjustable resistance values.

14. The circuit according to claim 2, wherein: The series resistance module includes one or more resistors, and the parallel resistance module includes one or more resistors.

15. The circuit according to any one of claims 1 to 14, characterized in that: The capacitor module includes a second fixed vacuum capacitor and a third fixed vacuum capacitor, the input end of the second fixed vacuum capacitor is connected to the output end of the first vacuum relay, the output end of the second fixed vacuum capacitor is connected to the input end of the third fixed vacuum capacitor, and the output end of the third fixed vacuum capacitor is grounded.

16. The circuit according to claim 15, characterized in that The capacitance of the third fixed vacuum capacitor is adjusted to adjust the voltage of the RF plasma load.

17. The circuit according to any one of claims 1 to 14, characterized in that: The circuit includes a fourth fixed vacuum capacitor and an inductor, the RF power supply is connected to the input end of the inductor, the output end of the inductor is connected to the input end of the first vacuum relay, the input end of the fourth fixed vacuum capacitor is connected to the input end of the inductor, and the output end of the fourth fixed vacuum capacitor is grounded.

18. The circuit according to any one of claims 1 to 14, characterized in that: The voltage value of the radio frequency plasma load obtained through the high power plasma load matching network is greater than the voltage value of the radio frequency plasma load obtained through the low power plasma load matching network.

19. The circuit according to any one of claims 1 to 14, characterized in that: The output power of the radio frequency power supply is within a target power range, which is 1-500 watts.

20. The circuit according to claim 19, characterized in that The output power of the radio frequency power supply is less than 30 watts.

Images