CN103377869B - Impedance matching methods, impedance matching system and plasma processing device - Google Patents

Abstract

The invention discloses a kind of impedance matching system, impedance matching methods and plasma processing device.This impedance matching methods makes the impedance matching between radio-frequency power supply and load by impedance matching network, described impedance matching network comprises: transformer, inductance and electric capacity, elementary and the described radio-frequency power supply of described transformer is connected, described inductance, described electric capacity and described load are connected on the secondary of described transformer successively, impedance matching methods obtains turn ratio adjustment amount according to described impedance real part deviation, and adjust according to the turn ratio of described turn ratio adjustment amount to described transformer; And obtain electric capacity adjustment amount according to described imaginary impedance deviation, and according to described electric capacity adjustment amount, described electric capacity is adjusted.This impedance matching methods reduces the difficulty of impedance matching, thus more easily realizes impedance matching.

Description

Impedance matching methods, impedance matching system and plasma processing device

Technical field

The present invention relates to microelectronics technology, particularly a kind of impedance matching methods, impedance matching system and plasma processing device.

Background technology

Plasma apparatus is widely used in the manufacture crafts such as semiconductor, solar cell and flat panel display, such as: using plasma equipment carries out thin film deposition or plasma etching etc.The mode of current plasma generation is a lot, and the power applied when producing plasma is exported by power supply, power supply divides from frequency range can comprise DC power supply usually, radio-frequency power supply and microwave power supply, wherein, radio-frequency power supply specifically can comprise: low frequency (30kHz-300kHz) power supply, intermediate frequency (300kHz-2MHz) power supply, high frequency (2MHz-30MHz) power supply and hyperfrequency (30MHz-300MHz) power supply.Radio-frequency power supply itself has characteristic impedance, and such as: this characteristic impedance is generally 50 Ω, and the load impedance of plasma load is not generally 50 Ω.According to transmission line theory, when the output impedance of radio-frequency power supply and the load impedance not conjugation of plasma load, that is: during impedance mismatch, the power output of radio-frequency power supply cannot be loaded on plasma load completely, power reflection can be produced, can cause power dissipation like this, the power being simultaneously reflected back radio-frequency power supply can cause damage by radio frequency power supply itself.For solving the characteristic impedance of radio-frequency power supply and the unmatched problem of load impedance of plasma load, usually need between radio-frequency power supply and plasma load, arrange an impedance matching network adjusting device.

Fig. 1 is a kind of structural representation of typical impedance matching system.As shown in Figure 1, this impedance matching system comprises: load, impedance matching network and in, low-frequency power.Wherein, impedance matching network comprises transformer, electric capacity C and inductance L, the input of transformer with in, low-frequency power is connected, the output of transformer and electric capacity C and load connect and compose path successively, and inductance L is connected in parallel on the output of transformer.Impedance matching network make the input impedance of impedance matching network with in, the output impedance conjugate impedance match of low-frequency power.As shown in Figure 1, the input impedance of impedance matching network is the impedance looked back from impedance matching network input.

In actual use, impedance matching is realized by adjustment transformer turn ratio and inductance L (or electric capacity C).The input impedance of impedance matching network comprises input impedance real part and input impedance imaginary part, in impedance matching process, the adjustment of inductance L (or electric capacity C) and the adjustment of transformer turn ratio all have impact to from input impedance real part and input impedance imaginary part, therefore realized by adjustment transformer turn ratio and inductance L (or electric capacity C) that impedance matching difficulty is comparatively large, efficiency is low, and the reliability of impedance matching is low.

Summary of the invention

The invention provides a kind of impedance matching methods, impedance matching system and plasma processing device, to reduce the difficulty of impedance matching and to improve the precision and efficiency of mating, thus impedance matching can be realized rapidly, reliably.

For achieving the above object, the invention provides a kind of impedance matching system, make the impedance matching between radio-frequency power supply and load by impedance matching network, described impedance matching network comprises: transformer, inductance and electric capacity, and the elementary and described radio-frequency power supply of described transformer is connected; Described inductance, described electric capacity and described load are connected on the secondary of described transformer successively, and described method comprises:

Obtain the output impedance of described radio-frequency power supply and the input impedance of described impedance matching network;

According to the output impedance of described radio-frequency power supply and the input impedance of described impedance matching network, obtain impedance real part deviation and imaginary impedance deviation;

If judge, described impedance real part deviation is greater than first and presets precision, obtains turn ratio adjustment amount, and adjust according to the turn ratio of described turn ratio adjustment amount to described transformer according to described impedance real part deviation;

If judge, described impedance real part deviation is less than or equal to first and presets precision and judge that described imaginary impedance deviation is greater than second and presets precision, obtain electric capacity adjustment amount according to described imaginary impedance deviation, and according to described electric capacity adjustment amount, described electric capacity is adjusted.

Wherein, the output impedance of described radio-frequency power supply comprises output impedance real part and output impedance imaginary part; The input impedance of described impedance matching network comprises input impedance real part and input impedance imaginary part; The difference of described output impedance real part and described input impedance real part is described impedance real part deviation, and the difference of described output impedance imaginary part and described input impedance imaginary part is described imaginary impedance deviation.

Wherein, described input impedance real part is Z_a=n²r_l, described input impedance imaginary part iswherein, n is the primary coil of described transformer and the turn ratio of secondary coil, R_lfor load equivalent resistance, C_lfor load equivalent electric capacity, L is inductance, and C is electric capacity, and ω is impedance factor, and j is the imaginary part of symbol.

Wherein, described adjust according to the turn ratio of described turn ratio adjustment amount to described transformer after also comprise:

Continue the step of the input impedance performing the described impedance matching network of described acquisition.

Wherein, described according to described electric capacity adjustment amount described capacitance adjusted after also comprise:

Continue the step of the input impedance performing the described impedance matching network of described acquisition.

Wherein, if judge, described imaginary impedance deviation is less than or equal to second and presets precision, then continue the step of the input impedance performing the described impedance matching network of described acquisition.

Wherein, also comprise after the input impedance of the described impedance matching network of described acquisition:

Judge the output impedance whether conjugate impedance match of the input impedance of described impedance matching network and described radio-frequency power supply;

If judge the input impedance of described impedance matching network and the non-conjugate impedance match of output impedance of described radio-frequency power supply, perform the input impedance of the described output impedance according to described radio-frequency power supply and described impedance matching network, obtain the step of impedance real part deviation and imaginary impedance deviation;

If judge the input impedance of described impedance matching network and the output impedance conjugate impedance match of described radio-frequency power supply, continue the step of the input impedance performing the described impedance matching network of described acquisition.

The present invention also provides a kind of impedance matching system, for making the impedance matching between radio-frequency power supply and load, it comprises: be arranged on the impedance matching network between described radio-frequency power supply and described load, mate to make the output impedance of the input impedance of described impedance matching network and described radio-frequency power supply, described impedance matching network comprises: transformer, inductance and electric capacity, elementary and the described radio-frequency power supply of described transformer is connected, described inductance, described electric capacity and described load are connected on the secondary of described transformer successively, thus make the size of described electric capacity not affect the real part of described input impedance.

Wherein, also comprise control unit, described control unit comprises:

Computing module, for according to the output impedance of described radio-frequency power supply and the input impedance of described impedance matching network, obtains impedance real part deviation and imaginary impedance deviation;

First judge module, for judging whether described impedance real part deviation is greater than first and presets precision, if judge, described impedance real part deviation is greater than first and presets precision, then obtain turn ratio adjustment amount according to described impedance real part deviation;

First Executive Module, adjusts for the turn ratio of described turn ratio adjustment amount to described transformer obtained according to described first judge module;

Second judge module, for judging that described imaginary impedance deviation is greater than second and presets precision, and if judge, described imaginary impedance deviation is greater than second and presets precision, obtains electric capacity adjustment amount according to described imaginary impedance deviation;

Second Executive Module, adjusts described electric capacity for the electric capacity adjustment amount obtained according to described second judge module.

Wherein, also comprise:

Input impedance detecting unit, for the input impedance of the output impedance and described impedance matching network that obtain described radio-frequency power supply;

The output impedance of described radio-frequency power supply comprises output impedance real part and output impedance imaginary part; The input impedance of described impedance matching network comprises input impedance real part and input impedance imaginary part;

Described computing module obtains described impedance real part deviation according to the difference of described output impedance real part and described input impedance real part, and obtains described imaginary impedance deviation according to the difference of described output impedance imaginary part and described input impedance imaginary part.

Wherein, described input impedance real part is Z_a=n²r_l, described input impedance imaginary part iswherein, n is the primary coil of described transformer and the turn ratio of secondary coil, R_lfor load equivalent resistance, C_lfor load equivalent electric capacity, L is inductance, and C is electric capacity, and ω is impedance factor, and j is the imaginary part of symbol.

Wherein, also comprise: output impedance detecting unit, for obtaining the output impedance of described radio-frequency power supply.

Wherein, also comprise: the 3rd judging unit, for the output impedance whether conjugate impedance match of the input impedance and described radio-frequency power supply that judge described impedance matching network.

The present invention also provides a kind of plasma processing device, comprise radio-frequency power supply, reaction chamber and impedance matching system, described impedance matching system is arranged between described radio-frequency power supply and described reaction chamber, to make the impedance matching between described radio-frequency power supply and described reaction chamber, described impedance matching system adopts described impedance matching system provided by the invention.

The present invention has following beneficial effect:

Impedance matching methods provided by the invention is connected on the secondary of transformer successively based on inductance, electric capacity and load, thus make the size of electric capacity not affect the real part of input impedance, when judging that impedance real part deviation is greater than the first default precision, the turn ratio of transformer is regulated to mate with the real part of the input impedance of the real part with impedance matching network that make the output impedance of radio-frequency power supply; When judging that imaginary impedance deviation is greater than the second default precision, the size of control capacittance is mated with the imaginary part of the input impedance of the imaginary part with impedance matching network that make the output impedance of radio-frequency power supply; That is, respectively the real part of impedance and imaginary part are adjusted, thus make the output impedance of radio-frequency power supply and the input resistant matching of impedance matching network.This impedance matching methods not only can reduce the difficulty of impedance matching, and improves precision and the efficiency of coupling, thus more rapidly, reliably makes the input impedance of the output impedance of radio-frequency power supply and described impedance matching network realize coupling.

In impedance matching system provided by the invention, inductance, electric capacity and load are connected on the secondary of transformer successively, with the real part making the size of described electric capacity not affect described input impedance, thus the matching process of the input impedance of impedance matching network and the output impedance of radio-frequency power supply can be simplified, and then improve precision and the efficiency of impedance matching.

As a preferred embodiment of impedance matching system of the present invention, control unit is when the first judge module judges whether impedance real part deviation is greater than the first default precision, the turn ratio of the first Executive Module adjustment transformer, mates with the real part of the input impedance of the real part with impedance matching network that make the output impedance of radio-frequency power supply; When the second judge module judges that imaginary impedance deviation is greater than the second default precision, adjusted the size of electric capacity by the second Executive Module, mate with the imaginary part of the input impedance of the imaginary part with impedance matching network that make the output impedance of radio-frequency power supply; Thus make the output impedance of radio-frequency power supply and the input resistant matching of impedance matching network.This impedance matching system not only can reduce the difficulty of impedance matching, and improves precision and the efficiency of coupling, thus more rapidly, reliably makes the input impedance of the output impedance of radio-frequency power supply and described impedance matching network realize coupling.

In addition, plasma processing device provided by the invention, makes the real part of the output impedance of radio-frequency power supply mate with the real part of the input impedance of impedance matching network by regulating the turn ratio of transformer; And, by the size of control capacittance, mate with the imaginary part of the input impedance of the imaginary part with impedance matching network that make the output impedance of radio-frequency power supply; Thus make the output impedance of radio-frequency power supply and the input resistant matching of impedance matching network; Therefore, this plasma processing device can more rapidly, reliably make the input impedance of the output impedance of radio-frequency power supply and described impedance matching network realize coupling.

Accompanying drawing explanation

Fig. 1 is a kind of structural representation of typical impedance matching system;

The structural representation of a kind of impedance matching system that Fig. 2 provides for the embodiment of the present invention one;

Fig. 3 is the equivalent circuit diagram of Fig. 2 middle impedance matching system;

The structural representation of a kind of impedance matching network that Fig. 4 provides for the embodiment of the present invention two;

Fig. 5 is the structured flowchart of control unit in inventive embodiments two;

The flow chart of a kind of impedance matching methods that Fig. 6 provides for the embodiment of the present invention three;

The flow chart of a kind of impedance matching methods that Fig. 7 provides for the embodiment of the present invention four;

The structural representation of the plasma processing device that Fig. 8 provides for the embodiment of the present invention five.

Embodiment

For making those skilled in the art understand technical scheme of the present invention better, below in conjunction with accompanying drawing, impedance matching system provided by the invention, impedance matching methods and plasma processing device are described in detail.

The structural representation of a kind of impedance matching system that Fig. 2 provides for the embodiment of the present invention one, Fig. 3 is the equivalent circuit diagram of Fig. 2 middle impedance matching system.See also Fig. 2 and Fig. 3, this impedance matching system comprises: impedance matching network 2, and it is arranged between radio-frequency power supply 1 and load 3, for the output impedance conjugate impedance match of the input impedance and radio-frequency power supply 1 that make impedance matching network 2.

Impedance matching network 2 comprises: transformer 21, inductance L and electric capacity C, and wherein, the elementary and radio-frequency power supply 1 of transformer 21 is connected, and inductance L, electric capacity C and load 3 are connected on the secondary of transformer 21 successively.

In the present embodiment, radio-frequency power supply 1 can be intermediate frequency power supply or low-frequency power, and electric capacity C adopts tunable capacitor.

Refer to Fig. 3, Rg is the characteristic impedance of radio-frequency power supply 1.The input impedance Z of impedance matching network 2 is Z=n²z₁, wherein, n is the turn ratio of transformer 2 primary coil and secondary coil; Z₁for the load impedance of looking backward from secondary (output) of transformer; And,

$Z_{1.}=R_L+j\[\mathrm{\ω}L-\frac{1}{\mathrm{\ω}C}-\frac{1}{{\mathrm{\ωC}}_L}\]$

Wherein, R_lfor load equivalent resistance; C_lfor load equivalent electric capacity; ω is impedance factor; L is inductance; C is electric capacity; J is the imaginary part of symbol.

Therefore draw,$Z=n^2\·R_L+{\mathrm{jn}}^2\·\[\mathrm{\ω}L-\frac{1}{\mathrm{\ω}C}-\frac{1}{{\mathrm{\ωC}}_L}\]$

As from the foregoing, the real part of the input impedance of impedance matching network 2 is Z_a=n²r_l; The imaginary part of the input impedance of impedance matching network 2 is

Therefore, can learn, when inductance L, electric capacity C and load 3 are connected on transformer 21 secondary successively, the real part Z of the input impedance of impedance matching network_aonly relevant with the turn ratio n of transformer 21; The imaginary part Z of the input impedance of impedance matching network_bnot only relevant with the turn ratio n of transformer 21, and relevant with the size of electric capacity C.In other words, when regulating the turn ratio n of transformer 21, the real part Z of the input impedance of impedance matching network_awith imaginary part Z_bchange simultaneously; When the size of control capacittance C, the real part Z of the only input impedance of impedance matching network_achange, and the imaginary part Z of the input impedance of impedance matching network_bdo not change.

The conjugate impedance match process of the input impedance of the present embodiment impedance matching network 2 and the input impedance of radio-frequency power supply 1 make use of above-mentioned characteristic just, changes control inputs imaginary impedance by adjustment electric capacity C, by adjustment turn ratio n control inputs impedance real part.Particularly, can first by adjusting turn ratio n by input impedance real part Z when impedance matching_aadjust, and then by adjustment electric capacity C, input impedance imaginary part is adjusted.Due to the adjustment of electric capacity C on input impedance real part without impact, therefore after input impedance imaginary part being adjusted by adjustment electric capacity C, the input impedance of impedance matching network 2 and the input impedance conjugate impedance match of radio-frequency power supply 1.

In the present embodiment, can be adjusted the turn ratio of transformer and/or electric capacity by artificial adjustment mode or automatic adjustment mode.

The structural representation of a kind of impedance matching network that Fig. 4 provides for the embodiment of the present invention two.As shown in Figure 4, the impedance matching network in the present embodiment also comprises on the basis of above-described embodiment one: input impedance detecting unit 22 and control unit 23, wherein,

Input impedance detecting unit 22 be arranged on radio-frequency power supply 1 and transformer 21 elementary between, it for detecting the input impedance of impedance matching network 2, and exports input impedance to control unit 23.

The input of control unit 23 is connected with input impedance detecting unit 22, control unit 23 output be connected with transformer 21 and electric capacity C.Control unit 23 for according to the input impedance adjustment turn ratio of transformer 21 and/or electric capacity with the output impedance conjugate impedance match of the input impedance and radio-frequency power supply 1 that make the impedance matching network after adjustment 2.

Fig. 5 is the structured flowchart of control unit in inventive embodiments two.See also Fig. 4 and Fig. 5, control unit 23 comprises:

Computing module 231, for according to the output impedance of described radio-frequency power supply and the input impedance of described impedance matching network, obtains impedance real part deviation and imaginary impedance deviation.

The output impedance of radio-frequency power supply can manually input, and also can obtain in real time in the process implementing impedance matching.The input impedance of impedance matching network can be obtained by input impedance detecting unit 22 examinations.

First judge module 232, for judging whether described impedance real part deviation is greater than first and presets precision, if judge, described impedance real part deviation is greater than first and presets precision, then obtain turn ratio adjustment amount according to described impedance real part deviation.

First Executive Module 233, first Executive Module 233 is connected with the adjustable side of transformer 21, and it adjusts for the turn ratio of described turn ratio adjustment amount to described transformer obtained according to described first judge module.First Executive Module 233 can switch the turn ratio of step-wise fashion adjustment transformer 21 by relay.

Second judge module 234, for judging that described imaginary impedance deviation is greater than second and presets precision, and if judge, described imaginary impedance deviation is greater than second and presets precision, obtains electric capacity adjustment amount according to described imaginary impedance deviation.

Second Executive Module 235, second Executive Module 235 is connected with the adjustable side of electric capacity C, and it adjusts described electric capacity for the electric capacity adjustment amount obtained according to described second judge module.Second Executive Module 235 can adjust the size of electric capacity C by stepping motor.

Preferably, the present embodiment also comprises output impedance detecting unit (not shown), it can the output impedance of automatic acquisition radio-frequency power supply 1, it can reduce the labour intensity of operating personnel, is more conducive to making the output impedance of the input impedance of impedance matching network 2 and radio-frequency power supply 1 realize conjugate impedance match.

Inductance L, electric capacity C and load are connected on the secondary of described transformer by the present embodiment successively, object is the real part not affecting input impedance in the size of control capacittance C, thus first can regulate the real part of input impedance, regulate the imaginary part of input impedance again, and then reduce the difficulty of matching of the input impedance of impedance matching network and the output impedance of radio-frequency power supply, simplify the matching process of the input impedance of impedance matching network and the output impedance of radio-frequency power supply, this not only can improve the efficiency of impedance matching, can also improve the precision of impedance matching.In addition, the automatic adjustment to input impedance real part and input impedance imaginary part can be realized by control unit, thus achieve Auto-matching process.

The embodiment of the present invention three provides a kind of impedance matching methods, and it makes the impedance matching between radio-frequency power supply and load by impedance matching system, and the impedance matching system of impedance matching system as described in embodiment one and embodiment two, repeats no more here.

The flow chart of a kind of impedance matching methods that Fig. 6 provides for the embodiment of the present invention three, as shown in Figure 6, this impedance matching methods comprises:

Step 101, obtain the output impedance of described radio-frequency power supply and the input impedance of described impedance matching network.

The output impedance of step 102 according to radio-frequency power supply and the input impedance of impedance matching network, obtain impedance real part deviation and imaginary impedance deviation.

If step 103 judges that impedance real part deviation is greater than first and presets precision, obtain turn ratio adjustment amount according to impedance real part deviation, and adjust according to the turn ratio of turn ratio adjustment amount to transformer.

If step 104 judges that impedance real part deviation is less than or equal to first and presets precision and judge that imaginary impedance deviation is greater than second and presets precision, obtain electric capacity adjustment amount according to imaginary impedance deviation, and according to electric capacity adjustment amount, electric capacity is adjusted.

The impedance matching methods that the present embodiment provides is connected on the secondary of transformer successively based on inductance, electric capacity and load, thus make the size of electric capacity not affect the real part of input impedance, when judging that impedance real part deviation is greater than the first default precision, the turn ratio of transformer is regulated to mate with the real part of the input impedance of the real part with impedance matching network that make the output impedance of radio-frequency power supply; When judging that imaginary impedance deviation is greater than the second default precision, the size of control capacittance is mated with the imaginary part of the input impedance of the imaginary part with impedance matching network that make the output impedance of radio-frequency power supply; That is, respectively the real part of impedance and imaginary part are adjusted, thus make the output impedance of radio-frequency power supply and the input resistant matching of impedance matching network.This impedance matching methods not only can reduce the difficulty of impedance matching, and improves precision and the efficiency of coupling, thus more rapidly, reliably makes the input impedance of the output impedance of radio-frequency power supply and described impedance matching network realize coupling.

The embodiment of the present invention four provides a kind of impedance matching methods, this impedance matching methods is based on impedance matching system, to make the impedance matching between radio-frequency power supply and load, the impedance matching system of impedance matching system as described in embodiment one and embodiment two, repeats no more here.The flow chart of a kind of impedance matching methods that Fig. 7 provides for the embodiment of the present invention four, as shown in Figure 7, this impedance matching methods comprises:

The input impedance of step 201, acquisition impedance matching network.

The output impedance of step 202, the input impedance judging impedance matching network and radio-frequency power supply whether conjugate impedance match, if judge the input impedance of impedance matching network and the non-conjugate impedance match of output impedance of radio-frequency power supply, performs step 203; If judge the input impedance of impedance matching network and the output impedance conjugate impedance match of radio-frequency power supply, then perform step 201.

In the present embodiment, the input impedance of impedance matching network 2 is Z, the output impedance of radio-frequency power supply is A, then step 202 is specifically as follows: whether the difference judging the output impedance A of radio-frequency power supply and the input impedance Z of impedance matching network is 0, if judge, the output impedance A of radio-frequency power supply and the input impedance Z of impedance matching network is not 0, then show the input impedance of impedance matching network and the non-conjugate impedance match of output impedance of radio-frequency power supply; If judge, the output impedance A of radio-frequency power supply and the input impedance Z of impedance matching network is 0, then show the input impedance of impedance matching network and the output impedance conjugate impedance match of radio-frequency power supply.

Step 203, according to the output impedance of radio-frequency power supply and the input impedance of impedance matching network, obtain impedance real part deviation and imaginary impedance deviation.

The output impedance of radio-frequency power supply only comprises output impedance real part A, and its output impedance imaginary part is 0; And the input impedance Z of impedance matching network comprises input impedance real part Z_awith input impedance imaginary part Z_b.Then this step specifically comprises: output impedance real part A is deducted input impedance real part Z_a, draw impedance real part deviation Z_ae, that is: Z_ae=A-Z_a; And deduct input impedance imaginary part Z by 0_b, draw imaginary impedance deviation Z_be, that is: Z_be=-Z_b.Such as: output impedance real part A=50 Ω.

Step 204, judge impedance real part deviation whether be greater than first preset precision, if judge impedance real part deviation be greater than first preset precision, perform step 205; If judge, impedance real part deviation is less than or equal to first and presets precision, performs step 207.

In the present embodiment, first presets precision can preset as required.In this step, if judge, impedance real part deviation is greater than first and presets precision, shows that input impedance real part needs adjust, then performs step 205; If judge, impedance real part deviation is less than or equal to first and presets precision, shows that input impedance real part is without the need to adjusting, then performs step 207.

Step 205, obtain turn ratio adjustment amount according to impedance real part deviation.

This step specifically can comprise: by impedance real part deviation Z_aewith the first regulation coefficient K₁be multiplied, draw turn ratio adjustment amount Δ n, that is: Δ n=K₁z_ae.

Step 206, to adjust according to the turn ratio of turn ratio adjustment amount to transformer, and perform step 201.

In the present embodiment, adjust according to the turn ratio n of turn ratio adjustment amount Δ n to transformer, thus realize the adjustment to input impedance real part.

Step 207, judge imaginary impedance deviation whether be greater than second preset precision, if judge imaginary impedance deviation be greater than second preset precision, perform step 208; If judge, imaginary impedance deviation is less than or equal to second and presets precision, performs step 201.

In the present embodiment, second presets precision can preset as required.In this step, if judge, imaginary impedance deviation is greater than second and presets precision, shows that input impedance imaginary part needs adjust, then performs step 208; If judge, imaginary impedance deviation is less than or equal to second and presets precision, shows that input impedance imaginary part is without the need to adjusting, then performs step 201.

Step 208, obtain electric capacity adjustment amount according to imaginary impedance deviation.

This step specifically can comprise: by imaginary impedance deviation Z_bewith the first regulation coefficient K₂be multiplied, draw turn ratio adjustment amount D_c, that is: D_c=K₂z_be.

Step 209, according to electric capacity adjustment amount, electric capacity to be adjusted, and perform step 201.

In the present embodiment, according to electric capacity adjustment amount D_celectric capacity C is adjusted, thus realizes the adjustment to input impedance imaginary part.

It should be noted that: when performing step 206, also input impedance imaginary part can be caused to change to the adjustment of turn ratio n, but the change of now input impedance imaginary part not necessarily can realize impedance matching, if unrealized impedance matching also needs the object by reaching the adjustment of electric capacity the adjustment of input impedance imaginary part, thus realizes impedance matching.

The impedance matching system that the impedance matching methods that the present embodiment provides provides by above-described embodiment one or embodiment two realizes.Wherein, if the impedance matching system that impedance matching methods is provided by embodiment two realizes, then step 201 can be performed by input impedance detecting unit 22, and step 202 can be performed by computing module 231, first judge module 232, first Executive Module 233, second judge module 234 in control unit 23 and the second Executive Module 235 to step 209.

Further, in the present embodiment, can also comprise before step 201: step 200, judge whether to exit the flow process of impedance matching methods, if not, then perform step 201; If so, then flow process terminates.Then in the present embodiment, after step 202, step 206, step 207 and step 209, first can perform step 200.

The impedance matching methods that the present embodiment provides is connected on the secondary of transformer successively based on inductance, electric capacity and load, thus make the size of electric capacity not affect the real part of input impedance, when judging that impedance real part deviation is greater than the first default precision, the turn ratio of transformer is regulated to mate with the real part of the input impedance of the real part with impedance matching network that make the output impedance of radio-frequency power supply; When judging that imaginary impedance deviation is greater than the second default precision, the size of control capacittance is mated with the imaginary part of the input impedance of the imaginary part with impedance matching network that make the output impedance of radio-frequency power supply; That is, respectively the real part of impedance and imaginary part are adjusted, thus make the output impedance of radio-frequency power supply and the input resistant matching of impedance matching network.This impedance matching methods not only to reduce the difficulty of impedance matching, and improves precision and the efficiency of coupling, thus more rapidly, reliably makes the input impedance of the output impedance of radio-frequency power supply and described impedance matching network realize coupling.

The structural representation of a kind of plasma processing device that Fig. 8 provides for the embodiment of the present invention five.As shown in Figure 8, plasma processing device comprises radio-frequency power supply 1, reaction chamber 5 and impedance matching system 2, impedance matching system 2 is arranged between radio-frequency power supply 1 and reaction chamber 5, to make the impedance matching between radio-frequency power supply 1 and reaction chamber 5, wherein, reaction chamber is as the load in above-described embodiment one and embodiment two, and impedance matching system adopts embodiment one and embodiment two middle impedance matching system.

The plasma processing device that the present embodiment provides, makes the real part of the output impedance of radio-frequency power supply mate with the real part of the input impedance of impedance matching network by regulating the turn ratio of transformer; And, by the size of control capacittance, mate with the imaginary part of the input impedance of the imaginary part with impedance matching network that make the output impedance of radio-frequency power supply; Thus make the output impedance of radio-frequency power supply and the input resistant matching of impedance matching network; Therefore, this plasma processing device can more rapidly, reliably make the input impedance of the output impedance of radio-frequency power supply and described impedance matching network realize coupling.

Be understandable that, the illustrative embodiments that above execution mode is only used to principle of the present invention is described and adopts, but the present invention is not limited thereto.For those skilled in the art, without departing from the spirit and substance in the present invention, can make various modification and improvement, these modification and improvement are also considered as protection scope of the present invention.

Claims (13)

1. an impedance matching methods, makes the impedance matching between radio-frequency power supply and load by impedance matching network, and described impedance matching network comprises: transformer, inductance and electric capacity, and the elementary and described radio-frequency power supply of described transformer is connected; It is characterized in that, described inductance, described electric capacity and described load are connected on the secondary of described transformer successively, and described method comprises:

Obtain the output impedance of described radio-frequency power supply and the input impedance of described impedance matching network;

According to the output impedance of described radio-frequency power supply and the input impedance of described impedance matching network, obtain impedance real part deviation and imaginary impedance deviation;

If judge, described impedance real part deviation is greater than first and presets precision, obtains turn ratio adjustment amount, and adjust according to the turn ratio of described turn ratio adjustment amount to described transformer according to described impedance real part deviation;

If judge, described impedance real part deviation is less than or equal to first and presets precision and judge that described imaginary impedance deviation is greater than second and presets precision, obtain electric capacity adjustment amount according to described imaginary impedance deviation, and according to described electric capacity adjustment amount, described electric capacity is adjusted.

2. impedance matching methods according to claim 1, is characterized in that, the output impedance of described radio-frequency power supply comprises output impedance real part and output impedance imaginary part; The input impedance of described impedance matching network comprises input impedance real part and input impedance imaginary part; The difference of described output impedance real part and described input impedance real part is described impedance real part deviation, and the difference of described output impedance imaginary part and described input impedance imaginary part is described imaginary impedance deviation.

3. impedance matching methods according to claim 2, is characterized in that, described input impedance real part is Z_a=n²r_l, described input impedance imaginary part iswherein, n is the primary coil of described transformer and the turn ratio of secondary coil, R_lfor load equivalent resistance, C_lfor load equivalent electric capacity, L is inductance, and C is electric capacity, and ω is impedance factor, and j is the imaginary part of symbol.

4. impedance matching methods according to claim 1, is characterized in that, described adjust according to the turn ratio of described turn ratio adjustment amount to described transformer after also comprise:

Continue the step of the input impedance performing the described impedance matching network of described acquisition.

5. impedance matching methods according to claim 1, is characterized in that, described according to described electric capacity adjustment amount described capacitance adjusted after also comprise:

Continue the step of the input impedance performing the described impedance matching network of described acquisition.

6. impedance matching methods according to claim 1, is characterized in that, if judge, described imaginary impedance deviation is less than or equal to second and presets precision, then continue the step of the input impedance performing the described impedance matching network of described acquisition.

7. impedance matching methods according to claim 1, is characterized in that, also comprises after the input impedance of the described impedance matching network of described acquisition:

Judge the output impedance whether conjugate impedance match of the input impedance of described impedance matching network and described radio-frequency power supply;

If judge the input impedance of described impedance matching network and the non-conjugate impedance match of output impedance of described radio-frequency power supply, perform the input impedance of the described output impedance according to described radio-frequency power supply and described impedance matching network, obtain the step of impedance real part deviation and imaginary impedance deviation;

If judge the input impedance of described impedance matching network and the output impedance conjugate impedance match of described radio-frequency power supply, continue the step of the input impedance performing the described impedance matching network of described acquisition.

8. an impedance matching system, for making the impedance matching between radio-frequency power supply and load, it comprises: be arranged on the impedance matching network between described radio-frequency power supply and described load, mate to make the output impedance of the input impedance of described impedance matching network and described radio-frequency power supply, described impedance matching network comprises: transformer, inductance and electric capacity, elementary and the described radio-frequency power supply of described transformer is connected, it is characterized in that, described inductance, described electric capacity and described load are connected on the secondary of described transformer successively, thus make the size of described electric capacity not affect the real part of described input impedance, described impedance matching system also comprises control unit, and described control unit comprises:

Computing module, for according to the output impedance of described radio-frequency power supply and the input impedance of described impedance matching network, obtains impedance real part deviation and imaginary impedance deviation;

First judge module, for judging whether described impedance real part deviation is greater than first and presets precision, if judge, described impedance real part deviation is greater than first and presets precision, then obtain turn ratio adjustment amount according to described impedance real part deviation;

First Executive Module, adjusts for the turn ratio of described turn ratio adjustment amount to described transformer obtained according to described first judge module;

Second judge module, for judging that described imaginary impedance deviation is greater than second and presets precision, and if judge, described imaginary impedance deviation is greater than second and presets precision, obtains electric capacity adjustment amount according to described imaginary impedance deviation;

Second Executive Module, adjusts described electric capacity for the electric capacity adjustment amount obtained according to described second judge module.

9. impedance matching system according to claim 8, is characterized in that, also comprises:

Input impedance detecting unit, for the input impedance of the output impedance and described impedance matching network that obtain described radio-frequency power supply;

The output impedance of described radio-frequency power supply comprises output impedance real part and output impedance imaginary part; The input impedance of described impedance matching network comprises input impedance real part and input impedance imaginary part;

Described computing module obtains described impedance real part deviation according to the difference of described output impedance real part and described input impedance real part, and obtains described imaginary impedance deviation according to the difference of described output impedance imaginary part and described input impedance imaginary part.

10. impedance matching system according to claim 9, is characterized in that, described input impedance real part is Z_a=n²r_l, described input impedance imaginary part iswherein, n is the primary coil of described transformer and the turn ratio of secondary coil, R_lfor load equivalent resistance, C_lfor load equivalent electric capacity, L is inductance, and C is electric capacity, and ω is impedance factor, and j is the imaginary part of symbol.

11. impedance matching systems according to claim 8, is characterized in that, also comprise:

Output impedance detecting unit, for obtaining the output impedance of described radio-frequency power supply.

12. impedance matching systems according to claim 8, is characterized in that, also comprise:

3rd judging unit, for the output impedance whether conjugate impedance match of the input impedance and described radio-frequency power supply that judge described impedance matching network.

13. 1 kinds of plasma processing devices, comprise radio-frequency power supply, reaction chamber and impedance matching system, described impedance matching system is arranged between described radio-frequency power supply and described reaction chamber, to make the impedance matching between described radio-frequency power supply and described reaction chamber, it is characterized in that, described impedance matching system adopts the impedance matching system described in claim 8-12 any one.