High-frequency power supply

Abstract

To suppress a transformer voltage Vt applied to a transformer and achieve miniaturization of a transformer, miniaturization of a high-frequency power supply, and cost reduction even under conditions of high plasma impedance.SOLUTION: An LC resonant circuit is provided on a secondary side of a transformer included in a high-frequency power supply. A capacitor current flowing through a capacitor forming the LC resonant circuit induces an inductance voltage on the inductance of wiring other than a primary coil of the transformer. The inductance voltage reduces the primary voltage applied to the transformer.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

[0001] The present invention relates to a high frequency power supply that supplies power to ignite and maintain a plasma in a reactive gas generator. [Background technology]

[0002] Reactive gases containing ions, radicals, atoms, and molecules are used in a variety of industrial applications, including gas processing of semiconductor substrates, and are generated by gas excitation through plasma discharge. Plasma is generated by the inductive coupling of gases supplied with power from a high-frequency power source. Patent Document 1 discloses a device that supplies power to ignite and maintain plasma.

[0003] 7A is a circuit diagram showing a known power supply configuration for supplying power to ignite and maintain a plasma. The high frequency power supply device 10A includes a switching power supply 20, a transformer 30 having a primary winding T1, a magnetic core (not shown), and a secondary winding T2, and a series resonant circuit 40 that supplies a high excitation voltage to the primary winding T1 of the transformer 30. The series resonant circuit 40 uses the primary winding T1 as a resonant inductor and a resonant capacitor C 40 is coupled in series between the switching power supply 20 and the primary winding T1. The switching power supply 20 generates an excitation voltage V s The resonant voltage V of the series resonant circuit 40 is applied. res is applied across the primary winding of the transformer 30.

[0004] 7B is a circuit diagram showing another known power supply configuration for supplying power to ignite and sustain a plasma. The high frequency power supply 10B includes a switching power supply 20, a transformer 30 having a primary winding T1, a magnetic core (not shown), and a secondary winding T2, and a series resonant circuit 40 that supplies a high excitation voltage to the primary winding T1 of the transformer 30. The series resonant circuit 40 includes an LC circuit having a resonant capacitor C 40 and inductor L 40 The capacitor C 40is coupled in parallel with the primary winding T1.

[0005] The switching power supply 20 generates an excitation voltage V s is applied to the series resonant circuit 40. The series resonant circuit 40 generates a resonant voltage V res is supplied to the primary winding T1 of the transformer 30, and a substantial resonant current I res and ignite the plasma. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 5490412 Summary of the Invention [Problem to be solved by the invention]

[0007] Reactive gas generators are required to operate under high-flow, high-pressure conditions in order to generate a large amount of reactive gas. Under these conditions, more power is required, and plasma impedance, which varies with parameters such as pressure and flow rate, tends to increase under high-flow, high-pressure conditions. An increase in plasma impedance inevitably leads to an increase in plasma voltage, which in turn increases the voltage applied to the transformer.

[0008] In the high frequency power supply device 10B shown in FIG. 7B, the turn ratio of the primary winding T1 and the secondary winding T2 of the transformer is set to 1:1, and the plasma voltage is set to V p , the plasma current is I p , transformer voltage is V t , transformer current is I t , the leakage inductance of the transformer is L leak Let's say.

[0009] Since the turns ratio is 1:1, the transformer current I t and plasma current I p Between them, It=I p There is a relationship between Transformer leakage inductance Lleak The voltage V applied to leak teeth, V leak =jω L leak I p …(1) is expressed as Transformer voltage V applied to the transformer t teeth, V t =V p +V leak …(2) The transformer voltage V in equation (2) t is the voltage V in equation (1). leak Applying V t =V p +jω·V leak I p …(3) It is expressed as:

[0010] An increase in transformer voltage increases the core loss of the transformer. Since increased core loss in a transformer can cause thermal runaway and damage the power supply, it is necessary to reduce core loss. The following are known common measures for reducing core loss: (a) Increase the cross-sectional area of ​​the transformer core. (b) Increase the number of windings in the transformer.

[0011] Increasing the cross-sectional area of ​​the transformer core would result in larger cores, which would increase the size of the transformer and its costs. Increasing the number of windings on the transformer would also result in the problem of the transformer becoming larger, as the plasma side is a vacuum environment structure and increasing the number of windings would complicate the structure. Therefore, in order to reduce core loss, it is unavoidable to face challenges such as increasing the size and cost of the transformer.

[0012] The present invention aims to suppress the transformer voltage Vt applied to a transformer even under conditions of high plasma impedance, thereby miniaturizing the transformer, miniaturizing the high-frequency power supply device, and reducing costs. [Means for solving the problem]

[0013] In the present invention, an LC resonant circuit is provided on the secondary side of a transformer included in a high-frequency power supply device. This LC resonant circuit generates an inductance voltage in the inductance on the wiring other than the coil on the primary side of the transformer due to the capacitor current flowing through the capacitor. This inductance voltage reduces the primary-side voltage applied to the transformer. Because the size of the transformer depends on the voltage applied to it, reducing the voltage applied to the transformer allows for a smaller transformer, which in turn allows for a smaller and more cost-effective high-frequency power supply device.

[0014] The high-frequency power supply device of the present invention is a high-frequency power supply device that supplies power to a plasma load, and includes a switching power supply, a transformer to which the switching power supply is connected on its primary side, and an LC resonant circuit provided on the secondary side of the transformer. The primary winding of the transformer is connected to the switching power supply, and the secondary winding forms a closed circuit with the plasma load. An LC resonant circuit is formed by a closed circuit between the secondary winding of the transformer and a capacitor, or a closed circuit between the tertiary winding of the transformer and a capacitor.

[0015] The transformer current I in the primary winding of the transformer t is the plasma current I flowing through the plasma load p and the capacitor current I flowing through the capacitor of the LC resonant circuit c and the combined current (I p +I c ) Transformer primary voltage V t is the wiring inductance L other than the primary winding coil w Plasma current I p The first inductance voltage V LP and the load voltage V generated in the plasma load p The sum voltage (V LP +V p ) and the wiring inductance L w The capacitor current I cThe second inductance voltage V Lc The voltage (V LP +V p -V Lc )

[0016] The primary voltage V of the transformer of a high-frequency power supply device that does not have an LC resonant circuit t is the first inductance voltage V LP and the load voltage V p The sum voltage (V LP +V p ), whereas the primary voltage V of the transformer of the high frequency power supply device of the present invention equipped with an LC resonant circuit t is the first inductance voltage V LP and the load voltage V p The sum voltage (V LP +V p ) to the second inductance voltage V Lc The voltage (V LP +V p -V Lc ), the second inductance voltage V Lc Only the transformer primary voltage V t The primary voltage V of this transformer can be reduced. t The reduction in voltage is achieved by providing an LC resonant circuit on the secondary side of the transformer.

[0017] Wiring inductance L w is the inductance of the wiring other than the coil on the primary side of the transformer, and the transformer current I t The transformer current I t As the plasma current I p and the capacitor current I c and the combined current (I p +I c ) flows. Wiring inductance L w is the plasma current I p The first inductance voltage V LP and the capacitor current I c The second inductance voltage V Lc The second inductance voltage VLc is the first inductance voltage V LP and load voltage V p Since the polarity is opposite to that of the primary voltage V t is the first inductance voltage V LP and the sum of the load voltage V p to the second inductance voltage V Lc The voltage (V LP +V p -V Lc )

[0018] Wiring inductance L w is the leakage inductance contained in the wiring other than the primary winding coil, as well as the additional inductance L add The additional inductance L add can be added by an optional inductor element.

[0019] Second inductance voltage V Lc is the leakage inductance L of the wiring inductance leak The capacitor current I c In addition to the voltage generated by the flow of leak In addition to this, there is an additional inductance L add The capacitor current I c is the voltage generated by the flow of

[0020] Second inductance voltage V Lc The capacitance C of the capacitor in the LC resonant circuit and the wiring inductance L w These parameters include the following. The voltage that suppresses the voltage on the primary side of the transformer can be adjusted using these parameters. The wiring inductance parameter can be adjusted by adding additional inductance to the wiring of the primary winding, and adding additional inductance can effectively suppress the voltage applied to the transformer. Note that these symbols are based on Figure 1.

[0021] The capacitor that constitutes the LC resonant circuit may be configured as a series circuit of multiple capacitor elements or a parallel circuit of multiple capacitor elements. When the capacitor of the LC resonant circuit is configured as a parallel circuit of multiple capacitor elements, the number of capacitor elements increases, but the small size of the capacitor elements can effectively suppress the voltage applied to the transformer. [Effects of the Invention]

[0022] As described above, according to the present invention, even under conditions where the plasma impedance is high, the transformer voltage V applied to the transformer t This suppresses the noise, reduces the size of the transformer, and makes it possible to reduce the size and cost of the high frequency power supply device. [Brief explanation of the drawings]

[0023] [Figure 1A] 1 is a circuit diagram for explaining a first configuration example of a high-frequency power supply device according to the present invention. [Figure 1B] 1 is a circuit diagram for explaining a first configuration example of a high-frequency power supply device according to the present invention. [Figure 2] FIG. 4 is a circuit diagram for explaining a second configuration example of a high-frequency power supply device according to the present invention. [Figure 3] FIG. 10 is a circuit diagram for explaining a third configuration example of a high frequency power supply device according to the present invention. [Figure 4] FIG. 10 is a circuit diagram for explaining a fourth configuration example of a high-frequency power supply device according to the present invention. [Figure 5] FIG. 10 is a circuit diagram for explaining a fifth configuration example of a high-frequency power supply device according to the present invention. [Figure 6] FIG. 10 is a circuit diagram for explaining a sixth configuration example of a high-frequency power supply device according to the present invention. [Figure 7A] FIG. 1 is a circuit diagram for explaining a configuration example of a conventional high frequency power supply device. [Figure 7B] FIG. 1 is a circuit diagram for explaining a configuration example of a conventional high frequency power supply device. DETAILED DESCRIPTION OF THE INVENTION

[0024] Hereinafter, first to sixth configuration examples of the high frequency power supply device of the present invention will be described with reference to FIGS. 1A to 6. FIG.

[0025] (First Configuration Example of High Frequency Power Supply Device) 1A and 1B, a first configuration example of a high-frequency power supply device of the present invention will be described. The high-frequency power supply device 1A includes a switching power supply 2, a transformer 3 having the switching power supply 2 connected to its primary side, and an LC resonant circuit 4A provided on the secondary side of the transformer 3.

[0026] The switching power supply 2 generates an excitation voltage V s is supplied to the transformer 3. The transformer 3 includes a primary winding T1, a secondary winding T2, and a tertiary winding T3, and the primary winding T1 is connected to the switching power supply 2 and has a stray inductance L1 on its wiring.

[0027] The primary winding T1 has a leakage inductance L leak including the wiring inductance L w The wiring inductance L w is the leakage inductance L of the primary winding T1 leak In addition to this, an additional inductance L added to the wiring of the primary winding T1 add The configuration may include:

[0028] The configuration shown in Figure 1A has a leakage inductance L leak including the wiring inductance L w The configuration shown in Figure 1B shows an example of the additional inductance L add and the wiring inductance L w as leakage inductance L leak and additional inductance L add An example including:

[0029] A load circuit is formed by connecting a plasma load R to both ends of the secondary winding T2 on the secondary side of the transformer 3. At this time, the plasma current I p flows, and the plasma voltage Vp occurs.

[0030] In the high frequency power supply device 1 of the present invention, a capacitor C1 is connected across the tertiary winding T3 on the secondary side of the transformer 3, and a closed circuit consisting of the inductance of the coil of the tertiary winding T3 and the capacitance of the capacitor C1 forms an LC resonant circuit 4A. A capacitor current I c flows, and the capacitor voltage V c occurs. Hereinafter, the same symbol C will be used to represent both the capacitor element and the capacitance representing the electrical characteristic of the capacitor element.

[0031] In the first configuration example, the turn ratio of the primary winding T1, the secondary winding T2, and the tertiary winding T3 is 1:1:1. Since the turn ratio is 1:1:1, the transformer current I flowing through the input terminal of the transformer 3 is t is the plasma current I p and the capacitor current I c The plasma voltage V p and the capacitor voltage V c are the equal voltages, and are expressed by the following equations (4) and (5), respectively. I t =I p +I c …(4) V c =V p …(5)

[0032] In the LC resonant circuit, the capacitor current I flows through the capacitor C1. c is expressed by the following equation (6). I c =jωC1 V p …(6)

[0033] Wiring inductance L w is the transformer current I t flows, the wiring inductance L w The wiring inductance voltage V w is expressed by the following equation (7). V w=jωL w I t …(7)

[0034] Here, by applying equations (4) and (6) to equation (7), the wiring inductance voltage V w is expressed by the following equation (8). V w =jωL w ·(I p +jωC1·V p ) =jωL w I p -ω 2 L w ·C1·V p …(8)

[0035] Transformer voltage V at the input end of transformer 3 t is the plasma voltage V p and wiring inductance voltage V w Since it is the sum of and, it is expressed by the following equation (9). V t =V p +V w =V p +jωL w I p -ω 2 L w ·C1·V p …(9)

[0036] where (V p +jωL w I p ) is the plasma voltage V p and plasma current I p The wiring inductance L w and the voltage generated in the transformer voltage V t The transformer voltage in the configuration without the LC resonant circuit 4A is equivalent to V to When expressed as: Equation (9) is expressed as the following Equation (10). V t =V to -ω 2 L w ·C1·V p…(10)

[0037] Equations (9) and (10) express the transformer voltage V applied to the transformer of the high frequency power supply device 1 having the LC resonant circuit 4A. t However, compared to a configuration without the LC resonant circuit 4A (ω 2 L w ·C1·V p ) voltage drop.

[0038] Therefore, by providing an LC resonant circuit on the secondary side of the transformer, the transformer voltage V t can be made smaller.

[0039] Voltage drop (ω 2 L w ·C1·V p ) is the wiring inductance L of the primary winding w , and the capacitance C1 of the capacitor that constitutes the LC resonant circuit are included as parameters. w , and / or the parameters of the capacitance C1 can be adjusted to adjust the voltage drop.

[0040] The wiring inductance L shown in Figure 1B w The configuration of the primary winding T1 has an additional inductance L add is connected, and the wiring inductance L w is the leakage inductance L leak and additional inductance L add The inductance is the sum of

[0041] This wiring inductance L w According to the configuration, the additional inductance L add By adjusting the inductance value of t can be adjusted.

[0042] (Second Configuration Example of High Frequency Power Supply Device) A second configuration example of a high-frequency power supply device of the present invention will be described with reference to Fig. 2. Like high-frequency power supply device 1A, high-frequency power supply device 1B includes a switching power supply 2, a transformer 3 connected to the primary side of the switching power supply 2, and an LC resonant circuit 4B provided on the secondary side of the transformer 3.

[0043] High frequency power supply device 1B of the second configuration example differs from high frequency power supply device 1A in the turns ratio of transformer 3, but other configurations are similar to high frequency power supply device 1A. The turns ratios of the primary winding T1, secondary winding T2, and tertiary winding T3 of the transformer of high frequency power supply device 1B are 1:1:k, and the turns ratio of the tertiary winding T3, which forms an LC resonant circuit, is k.

[0044] Since the turns ratio is 1:1:k, the plasma voltage V p and the capacitor voltage V c is expressed by the following equation (11). V c = k V p …(11)

[0045] The plasma voltage V expressed by equation (11) p and the capacitor voltage V c When the relationship between the wiring inductance voltage V and the wiring inductance voltage V is applied to each equation obtained in the high frequency power supply device 1A of the first configuration example, w is expressed by the following equation (12). V w =jωL w ·(I p +jωC1·k·V p ) =jωL w I p -ω 2 L w C1 kV p …(12)

[0046] Transformer voltage V at the input end of transformer 3 t are expressed by the following equations (13) and (14). V t =V p +V w =V p +jωLw I p -ω 2 L w C1 kV p …(13) V t =V to -ω 2 L w C1 kV p …(14)

[0047] Equations (13) and (14) express the transformer voltage V applied to the transformer of the high frequency power supply device 1 having the LC resonant circuit 4B. t However, compared to a configuration without the LC resonant circuit 4A (ω 2 L w C1 kV p ) and that the voltage drop is k times as large as that of the LC resonant circuit 4A of the first configuration example. Therefore, by adjusting the turns ratio of the third winding of the transformer 3 relative to the turns ratio of the first winding and the turns ratio of the second winding, the transformer voltage V t can be adjusted.

[0048] (Third Configuration Example of High Frequency Power Supply Device) A third configuration example of a high-frequency power supply device of the present invention will be described with reference to Fig. 3. Like high-frequency power supply device 1A, high-frequency power supply device 1C includes a switching power supply 2, a transformer 3 connected to the primary side of the switching power supply 2, and an LC resonant circuit 4C provided on the secondary side of the transformer 3.

[0049] The LC resonant circuit 4A of the high frequency power supply device 1A in the first configuration example has one capacitor C1 connected to the tertiary winding T3, whereas the LC resonant circuit 4C of the high frequency power supply device 1C in the third configuration example has two capacitors C1 and C2 connected in parallel to the tertiary winding T3. The capacitance of the LC resonant circuit 4C in which the capacitors C1 and C2 are connected in parallel is expressed as (C1 + C2).

[0050] According to this LC resonant circuit 4C, the wiring inductance voltage V w is expressed by the following equation (15). V w =jωL w ·(I p +jω(C1+C2)·V p ) =jωL w I p -ω 2 L w (C1+C2) V p …(15) Here, the turns ratio of the primary winding T1, the secondary winding T2, and the tertiary winding T3 of the transformer of the high frequency power supply device 1C is set to 1:1:1.

[0051] Transformer voltage V at the input end of transformer 3 t are expressed by the following equations (16) and (17). V t =V p +V w =V p +jωL w I p -ω 2 L w (C1+C2) V p …(16) V t =V to -ω 2 L w (C1+C2) V p …(17)

[0052] Equations (16) and (17) express the transformer voltage V applied to the transformer of the high frequency power supply device 1 having the LC resonant circuit 4C. t This indicates that the voltage drop is (C1+C2) / C1 times that of the LC resonant circuit 4A of the first configuration example. Therefore, by configuring the capacitance of the LC resonant circuit 4C with the parallel connection of capacitors C1 and C2, the transformer voltage V t can be adjusted.

[0053] (Fourth Configuration Example of High Frequency Power Supply Device) A fourth configuration example of a high-frequency power supply device of the present invention will be described using Fig. 4. Like high-frequency power supply device 1A, high-frequency power supply device 1D includes a switching power supply 2, a transformer 3 connected to the switching power supply 2 on its primary side, and an LC resonant circuit 4D provided on the secondary side of transformer 3.

[0054] The LC resonant circuit 4D of the high-frequency power supply device 1D in the fourth configuration example has a configuration in which two capacitors are connected in parallel, similar to the LC resonant circuit 4C of the high-frequency power supply device 1C in the third configuration example. The LC resonant circuit 4C has capacitors C1 and C2 connected in parallel to a third winding T3 on the secondary side of a transformer 3. In contrast, the LC resonant circuit 4D has a third winding T3 and a fourth winding T4 on the secondary side of the transformer 3, and capacitors C3 and C4 are connected to the third winding T3 and the fourth winding T4, respectively, to form respective LC resonant circuits.

[0055] The inductance of the third winding T3 forms an LC resonant circuit together with the capacitance of the capacitor C3, and the inductance of the fourth winding T4 forms an LC resonant circuit together with the capacitance of the capacitor C4.

[0056] The capacitance of the LC resonant circuit 4D is expressed as (C1+C2) in the same way as the capacitance of the LC resonant circuit 4C.

[0057] Here, if the turn ratio of the third winding T3 and the fourth winding T4 to the first winding T1 and the second winding T2 is 1:1:k3:k4, the wiring inductance voltage V of the LC resonant circuit 4D is w is expressed by the following equation (18). V w =jωL w ·(I p +jω(k3 C3+k4 C4) V p ) =jωL w I p -ω 2 L w (k3 C3 + k4 C4) V p …(18)

[0058] Transformer voltage V at the input end of transformer 3 t are expressed by the following equations (19) and (20). V t =V p +V w =V p +jωL w I p -ω 2 L w (k3 C3 + k4 C4) V p …(19) V t =V to -ω 2 L w (k3 C3 + k4 C4) V p …(20)

[0059] Equations (19) and (20) express the transformer voltage V applied to the transformer of the high frequency power supply device 1 having the LC resonant circuit 4D. t This indicates that the voltage drop is (k3·C3+k4·C4) / C1 times that of the LC resonant circuit 4A of the first configuration example. Therefore, by configuring the LC resonant circuit 4D with multiple LC resonant circuits, the transformer voltage V t can be adjusted.

[0060] (Fifth Configuration Example of High Frequency Power Supply Device) A fifth configuration example of a high frequency power supply device of the present invention will be described using Fig. 5. Like high frequency power supply device 1A, high frequency power supply device 1E includes a switching power supply 2, a transformer 3 having the switching power supply 2 connected to its primary side, and an LC resonant circuit 4E provided on the secondary side of transformer 3.

[0061] The LC resonant circuit 4A of the high-frequency power supply 1A according to the first configuration example has a configuration in which one capacitor C1 is connected to the tertiary winding T3, whereas the LC resonant circuit 4E of the high-frequency power supply 1E according to the fifth configuration example has a configuration in which two capacitors C1 and C2 are connected in series to the tertiary winding T3. The capacitance of the LC resonant circuit 4E in which the capacitors C1 and C2 are connected in series is expressed as (C1·C2 / (C1+C2)).

[0062] According to this LC resonant circuit 4E, the wiring inductance voltage V w is expressed by the following equation (21). V w =jωL w ·(I p +jω(C1 C2 / (C1+C2)) V p ) =jωL w I p -ω 2 L w (C1 C2 / (C1+C2)) V p …(twenty one) Here, the turn ratio of the primary winding T1, the secondary winding T2, and the tertiary winding T3 of the transformer of the high frequency power supply device 1E is set to 1:1:1.

[0063] Transformer voltage V at the input end of transformer 3 t are expressed by the following equations (22) and (23). V t =V p +V w =V p +jωL w I p -ω 2 L w (C1 C2 / (C1+C2)) V p …(twenty two) V t =V to -ω 2 L w (C1 C2 / (C1+C2)) V p …(twenty three)

[0064] Equations (22) and (23) express the transformer voltage V applied to the transformer of the high-frequency power supply device 1 having the LC resonant circuit 4E. t This indicates that the voltage drop is {(C1·C2 / (C1+C2)} / C1 times that of the LC resonant circuit 4A of the first configuration example. Therefore, by configuring the capacitance of the LC resonant circuit 4E as a series connection of capacitors C1 and C2, the transformer voltage V t can be adjusted.

[0065] (Sixth Configuration Example of High Frequency Power Supply Device) A sixth configuration example of a high frequency power supply device of the present invention will be described with reference to Fig. 6. Similar to high frequency power supply device 1A, high frequency power supply device 1F includes a switching power supply 2, a transformer 3 having the switching power supply 2 connected to its primary side, and an LC resonant circuit 4B provided on the secondary side of transformer 3.

[0066] High frequency power supply devices 1A to 1E form an LC resonant circuit using the coils of tertiary windings T3 to T4 that are provided separately from the secondary winding T2 to which the plasma load R is connected. In contrast, high frequency power supply device 1F according to the sixth configuration example forms an LC resonant circuit using the coil of the secondary winding T2 to which the plasma load R is connected.

[0067] In FIG. 6, an LC resonant circuit 4F is formed by connecting a capacitor C5 in parallel to the coil of the secondary winding T2.

[0068] The LC resonant circuit 4F according to the sixth configuration example is electrically equivalent to the LC resonant circuit 4A according to the first configuration example, so the transformer voltage V t are expressed by the following equations (24) and (25). V t =V p +V w =V p +jωL w I p -ω 2 L w ·C5·V p …(twenty four) V t =V to -ω 2 L w ·C5·V p …(twenty five)

[0069] Equations (25) and (26) express the transformer voltage V applied to the transformer of the high frequency power supply device 1 having the LC resonant circuit 4F. t However, compared to a configuration without the LC resonant circuit 4F (ω 2 L w ·C5·V p ) voltage drop. [Industrial Applicability]

[0070] The high frequency power supply device of the present invention can be applied to a high frequency power supply device that supplies high frequency power to a plasma load such as a plasma processing device that uses plasma to form a thin film, modify a surface, or remove a thin film such as etching or ashing in thin film processing of semiconductors, liquid crystals, etc. [Explanation of symbols]

[0071] 1,1A,1B,1C,1D,1E,1F High frequency power supply 2. Switching power supply 3. Transformer 4A,4B,4C,4D,4E,4F LC resonant circuit 10A high frequency power supply 10B high frequency power supply 20 Switching power supply 30 Transformer 40 Series resonant circuit C1, C2, C3, C4, C5 capacitors C 40 Resonant Capacitor I c Capacitor Current I p Plasma Current I res resonant current I t Transformer Current L1 stray inductance L 40 inductor L add Additional Inductance L leak Leakage Inductance R Plasma Load T1 primary winding T2 secondary winding T3 tertiary winding T44 primary winding V c Capacitor Voltage V p Plasma Voltage V res Resonance Voltage V s Excitation Voltage V t Transformer Voltage V w Wiring inductance voltage

Claims

1. A high frequency power supply device for supplying power to a plasma load, A switching power supply, a transformer having the switching power supply connected to its primary side; an LC resonant circuit provided on the secondary side of the transformer; Equipped with The secondary winding of the transformer forms a closed circuit with a plasma load, the LC resonant circuit is formed by a closed circuit of a tertiary winding of the transformer and a capacitor, or a closed circuit of a secondary winding of the transformer and a capacitor, a transformer current of the primary winding of the transformer is a combined current of a plasma current flowing through the plasma load and a capacitor current flowing through the capacitor of the LC resonant circuit, a transformer voltage on the primary side of the transformer is a voltage obtained by subtracting a second inductance voltage generated in the wiring inductance by the capacitor current from a sum voltage of a first inductance voltage generated in a wiring inductance other than the coil of the primary winding by the plasma current and a load voltage generated in the plasma load; High frequency power supply.

2. the wiring inductance is the leakage inductance of the primary winding, The second inductance voltage is a voltage generated in the leakage inductance by the capacitor current.

2. The high frequency power supply device according to claim 1.

3. The wiring inductance further comprises an additional inductance; The second inductance voltage is a voltage generated in the leakage inductance and the additional inductance by the capacitor current.

3. The high frequency power supply device according to claim 2.

4. The second inductance voltage is determined based on the capacitance of the capacitor and the wiring inductance as parameters.

2. The high frequency power supply device according to claim 1.

5. The capacitor is configured as a series circuit or a parallel circuit of a plurality of capacitor elements.

2. The high frequency power supply device according to claim 1.

Images