JP2004336721A - Microwave power supply unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable adjustment of different voltages in an initial stage and a high output stage, so that good performance evaluation can be obtained with regard to both a barrier capability and an adhesive property. <P>SOLUTION: A voltage set in an voltage set section 12-1 of a voltage regulator 12, or a feedback voltage received in a feedback section 18-1 from a high-voltage rectifier 15-1 is forwarded to a diode bridge 19-14 in a Toulon circuit 19-13. A trigger of which generation timing is produced based on the above voltage set or the feedback voltage is forwarded from a pulse transformer 19-17 to an SCR phase controller 13-1. In this SCR controller 13-1, the phase control of an alternating current voltage caused by the trigger is performed. This alternating current voltage is then boosted, rectified, and applied to a microwave generator 17. With this applied voltage, the microwave generator 17 generates a microwave, in which the emission intensity and an ON time are controlled. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a microwave power supply device, and more particularly to a microwave power supply device that controls a microwave output by phase control of a sine wave or pulse width control of a pulse wave.

In recent years, with the rapid advancement of an advanced information society, higher performance and higher density of semiconductor devices, recording media, optical fibers, and the like have been promoted. Among these electronic component and communication equipment manufacturing process technologies, thin film forming and processing technologies play an important role.
As the dry process in this thin film formation / processing technique, there are physical vapor deposition and chemical vapor deposition, which are used for applications utilizing their respective characteristics. Of these, chemical vapor deposition is superior in film throwing power and adhesion strength, and can produce powders, fiber whiskers, etc., so plasma CVD (Chemical Vapor deposition), which enables high-quality thin film formation at low temperatures, is the center. Its use is spreading.

In addition to the electronic components and optical fibers described above, thin film formation using plasma CVD is possible in addition to the manufacture of semiconductors such as solar cells and semiconductor lasers, electrophotography using amorphous silicon photoreceptors, optical thin films, and magnetic properties. In addition, it is also used for forming a protective film such as a tool or mold coding.
In recent years, it has been widely used for oxygen permeation prevention coating on plastics, high-performance coatings on glass, other coatings on steel materials, PET bottles, etc., and production of silica and alumina powders.
In addition to plasma CVD, chemical vapor deposition includes thermal CVD and photo-CVD as methods for exciting chemical reactions.

By the way, in the case of performing plasma type chemical vapor deposition, a microwave power supply device that transmits microwaves through a waveguide is necessary to generate plasma in a process chamber.
The microwave power supply device refers to a power supply device that supplies electric power to cause a microwave generation unit (for example, a magnetron) to emit microwaves. FIG. 21 (iron transformer system) and FIG. 22 (inverter system) show conventional general circuit configurations of this microwave power supply device.

For example, a microwave power supply apparatus 100 using an iron transformer system transforms a power supply voltage supplied from an AC power supply (commercial power supply) 110 to a high voltage by a transformer circuit 120 as shown in FIG. And full-wave rectified, and this voltage is applied to the microwave generator 140 (for example, a magnetron). That is, in this case, the full-wave rectified voltage is applied to the microwave generation unit 140 as it is.
Thereby, the microwave generation part 140 discharge | releases the microwave of the output intensity according to the average value of the applied voltage (for example, refer patent document 1, 1st prior art).

On the other hand, as shown in FIG. 22, a microwave power supply apparatus 200 using an inverter system converts a power supply voltage supplied from an AC power supply (commercial power supply) 210 into a direct current by a rectifier circuit 220 (for example, a diode bridge). After conversion, the ripples and the like are removed by a smoothing circuit 230 (for example, a resistor and a capacitor), and the frequency is increased by an inverter circuit 240 (for example, a half-bridge inverter composed of a switching element (transistor) 241 and a capacitor). A high frequency voltage is made high by a circuit 250 (eg, a high frequency transformer), and a high frequency high voltage is applied to a microwave generator 270 (eg, a magnetron) by a voltage doubler rectifier circuit 260 (eg, a diode or a capacitor) For example, see Patent Document 2 The prior art.) Of.
Also by this, the microwave generation part 270 emits the microwave of the output intensity according to the applied voltage.

Moreover, in the microwave power supply device using the inverter system, in order to change the microwave output generated from the microwave generation unit, the voltage (applied voltage) applied to the microwave generation unit is ON / OFF controlled. There is something.
For example, as shown in FIG. 22, the switching element 241 provided in the inverter circuit 240 is controlled by the switching control unit (not shown) to adjust the ON / OFF control (the ratio of each time between the ON state and the OFF state). ), The ON time (pulse width) of the voltage (pulse wave) applied to the microwave generator 270 is adjusted to change the microwave output (see, for example, Patent Documents 3 and 4). The third prior art.).

In this case, the average voltage value of the voltage applied to the microwave generator 270 (that is, the power supplied to the microwave generator 270) is changed by adjusting the time ratio of the ON state to the OFF state of the switching element 241. Can do. For this reason, the microwave output of the microwave generation part 270 can be changed.
JP 2002-323222 A (2nd page, FIG. 13) JP-A-5-062774 (page 2-3, Fig. 2) JP 2001-185340 A (page 2-3, FIG. 11) JP 2001-332934 A (page 2-3, FIG. 5)

However, the first and second prior arts cannot adjust the voltage applied to the microwave generation unit, and thus cannot change the microwave output along with this adjustment.
On the other hand, the third prior art can change the output of the microwave by adjusting the ON time of the applied voltage of the microwave generator, but the adjustment target is only the ON time of the applied voltage. However, simply applying the third prior art to a CVD microwave power supply device has a problem that desirable thin film characteristics cannot be obtained.

As shown in FIG. 23, the chemical vapor deposition process by the plasma method includes, for example, an initial stage (low output state) in which microwaves are generated with low output intensity, a startup stage in which the output intensity gradually increases, It can be considered that it is divided into a high output stage (high output state) in which microwaves are generated with output intensity.
When plasma deposition is performed in such a process, in the process chamber, the filled processing gas plasma is first ignited by a low-power microwave and then contains a large amount of organic components in the low-power state. A thin film layer is formed on the substrate (on the object on which the thin film is deposited), and then a hard thin film with few organic components is formed in a high output state.
The laminated thin film thus formed improves the adhesion between the substrate and the hard thin film layer due to the thin film initial layer containing a large amount of organic components.

Here, by adjusting the ON time of the applied voltage of the microwave generation part using the third conventional technique, the microwave output is changed to try to obtain a good thin film having excellent adhesion. Can be considered.
However, since the formation of a thin film on a substrate is performed with the intention of preventing permeation of oxygen and moisture, not only adhesion but also excellent barrier properties (gas barrier properties) are required as the quality of the thin film.
In this regard, when the microwave output is adjusted using the third prior art, there is a problem that only one of the adhesion and barrier properties can be improved, but both cannot be improved. It was.

FIGS. 24 (1) and 24 (2) show specific inspection results of each characteristic (barrier property, adhesion) of the thin film when the microwave output is adjusted using the third conventional technique.
Note that the “ON time” in FIGS. 1A and 1B indicates the ON time of the voltage applied to the microwave generator in the initial stage (or high output stage). Also, the smaller the value of each characteristic (barrier property, adhesion), the better.
Also, in the figure, “Low output time” is the time in the low output state, “Start-up time” is the time in the start-up stage, and “High output time” is in the high output state. Each time.

For example, when the microwave output is changed using the third conventional technique, the ON time of the voltage applied to the microwave generator is adjusted. When the peak output (indicated by the detected voltage value of the power monitor) is increased, the peak output of the microwave at the time of high output also increases. Therefore, the barrier property (assuming that the gas barrier property of PET alone is 1, the smaller the value). Good) is better. However, the adhesion (the smaller the value of the amount of film reduction after environmental aging, the better) was worse ((1) in the figure).
On the other hand, if the ON time at low output is shortened and the peak output at low output is reduced, the microwave peak output at high output is reduced, so that the adhesion is improved, but the barrier property is deteriorated. ((2) in the figure).

  As described above, for example, when the microwave output intensity is changed by the third prior art in the initial stage (low output state), good results can be obtained for either the barrier property or the adhesion property. However, it was not always possible to obtain good results for the other, and there was a concern that the quality of the thin film was deteriorated.

On the other hand, for example, if the peak output at the time of high output can be increased while shortening the ON time of the applied voltage of the microwave generation unit at the time of low output, good results in both barrier properties and adhesion can be obtained. Is obtained ((3) in the figure).
For this reason, in the CVD technique, it is possible to adjust both the ON time and the peak voltage of the voltage applied to the microwave generation unit, and to form a thin film with good barrier properties and adhesion. The provision of technology was desired.

In addition, increasing the microwave output intensity can improve the light emission of the plasma in the process chamber. Conventionally, in order to increase the microwave output intensity, the ON time is increased or the microwave is increased. The average value of the voltage applied to the generator was increased.
Then, as described above, although the barrier property can be improved as the thin film performance, the adhesion is deteriorated.
For this reason, provision of the technique which can make the adhesiveness of a thin film favorable while improving the luminous property of plasma was anticipated.

Furthermore, if the ON time can be shortened while increasing the microwave output intensity in the initial stage (low output state), it is possible to shorten not only the initial stage but also the high output stage ( FIG. 24 (4)). For this reason, the time which the whole thin film formation process by plasma CVD requires can be shortened.
For this reason as well, it has been demanded to provide a technique capable of independently adjusting the ON time and the peak voltage of the voltage applied to the microwave generator.

In addition, in the high output stage, it is necessary to perform control different from the control of the applied voltage in the initial stage.
In the initial stage, as shown in FIG. 24 (3), both the barrier property and adhesion of the thin film can be improved when the ON time is short and the peak output is high. In particular, the improvement in adhesion is remarkable.
On the other hand, in the high output stage, as shown in FIG. 25, as the ON time is longer and the peak output is higher, the barrier property (oxygen barrier property: smaller value is better) can be improved.
For this reason, it has been desired to provide a technique capable of performing an adjustment different from the adjustment of the applied voltage at the initial stage at the high output stage so that good thin film characteristics can be obtained.

  The present invention has been considered in view of the above circumstances, and the peak voltage of the voltage applied to the microwave generation unit and the ON time are obtained so that good performance evaluation can be obtained for both barrier properties and adhesion. A micro that makes it possible to adjust each applied voltage and to adjust the applied voltage differently in the initial stage and the high output stage, and to shorten the time required for the entire thin film formation by plasma CVD. An object is to provide a wave power supply device.

  In order to achieve this object, a microwave power supply device according to claim 1 of the present invention is a microwave power supply device that drives a microwave generator by applying a voltage, and determines a peak value of an applied voltage. An adjustment circuit, an ON time adjustment circuit that determines the ON time of the applied voltage, and an application that forms a waveform of the applied voltage based on the peak output from the voltage value adjustment circuit and / or the ON time from the ON time adjustment circuit. And a voltage control circuit.

When the microwave power supply device has such a configuration, not only the ON time adjustment circuit that adjusts the ON time of the applied voltage to the microwave generator, but also the voltage value that adjusts the peak output (maximum voltage value) of the applied voltage. Since the adjustment circuit is provided, both the ON time and the peak output can be individually adjusted.
In addition, the applied voltage control circuit forms a waveform of the applied voltage based on both the peak output (voltage set value) adjusted by the voltage value adjusting circuit and the ON time adjusted by the ON time adjusting circuit. By adjusting the peak output and the ON time, the microwave output from the microwave generator to which the applied voltage is applied can be changed to a desired waveform.

Furthermore, by adjusting the peak output and the ON time so that the applied voltage can be controlled, the applied voltage can be formed in an appropriate waveform in the initial stage and the high output stage when the thin film is formed.
For example, in the initial stage, by increasing the voltage setting value and shortening the ON time, good characteristics as shown in FIG. 24 (3) can be obtained, while in the high output stage, the voltage setting is performed. By increasing the value and extending the ON time, a good oxygen barrier property as shown in FIG. 25 can be obtained.
Accordingly, in the thin film formation by plasma CVD, it is possible to improve both the barrier properties and the adhesion properties that could not be achieved by the conventional microwave power supply device.

In addition, since the two parameters of the peak output (voltage set value) and the ON time for the voltage applied to the microwave generator can be adjusted independently, the initial stage and the high level when the thin film is formed can be adjusted. In the output stage, the voltage setting value and the ON time can be adjusted differently.
In the high output stage, if the voltage set value is too high, if the heat resistance of the thin film processing target (for example, plastic or resin) is low, the processing target itself may be deformed. It is preferable to make the voltage setting value slightly lower while extending the ON time.

Furthermore, since the output intensity can be increased while shortening the ON time of the applied voltage in the initial stage of plasma CVD thin film deposition, each performance (barrier property and adhesion) of the thin film can be improved, Luminescence can also be improved.
In addition, in the initial stage, the ON time can be shortened while increasing the microwave output intensity, and the high output time in the high output stage can be shortened (FIG. 24 (4)), which is necessary for the entire thin film formation by plasma CVD. Time can be shortened.

  Further, in the microwave power supply device according to claim 2, the applied voltage control circuit includes an inverter circuit unit that forms the applied voltage in a high-frequency pulse waveform, and a peak output from the voltage value adjustment circuit and / or an ON time adjustment. An inverter drive circuit unit that drives the inverter circuit unit based on the ON time from the circuit is provided.

When the microwave power supply device has such a configuration, even in a microwave power supply device that employs an inverter system, it is based on both the peak output set by the voltage value adjustment circuit and the ON time set by the ON time adjustment circuit. The applied voltage can be adjusted.
For this reason, it is possible to control the microwave generated from the microwave generator based on the adjusted applied voltage, and thus it is possible to form a thin film having both excellent barrier properties and adhesion.

  Further, in the microwave power supply device according to claim 3, the inverter circuit unit includes a switching element that forms an applied voltage at a high frequency, and the inverter drive circuit unit includes a peak output from the voltage value adjustment circuit, and / or Based on the ON time from the ON time adjusting circuit, a setting variable control unit that forms a control signal indicating an adjustment value of the peak output and / or ON time, and the switching element of the inverter circuit unit is driven based on the control signal. The switching element driving unit is included.

When the microwave power supply device has such a configuration, the switching element driving unit (gate driving circuit) shows each value or fluctuation value (adjustment value) of the peak output (voltage setting value) and ON time of the applied voltage. Based on the control signal, the switching element (for example, a transistor) can be driven and controlled. Accordingly, the switching element can convert the rectified voltage into an intermittent high-frequency pulse waveform based on both the adjusted voltage setting value and the ON time.
For this reason, the microwave generation unit generates a microwave based on the applied voltage in which the voltage setting value and the ON time are adjusted. Therefore, when forming a thin film by plasma CVD, the microwave power supply device adjusts the voltage setting value and ON time to form a microwave in a desired waveform and coats a thin film with good barrier properties and adhesion. it can.

  The microwave power supply device according to claim 4 is a microwave power supply device that drives a microwave generation unit by applying a voltage, a voltage value adjustment circuit that determines a peak output of the applied voltage, and the voltage value adjustment An ON time adjustment circuit that determines the ON time of the applied voltage based on the peak output of the applied voltage determined by the circuit, and an applied voltage control that forms a waveform of the applied voltage based on the ON time from the ON time adjustment circuit And a circuit.

If the microwave power supply device has such a configuration, in the microwave power supply device adopting the iron transformer system, the peak output of the applied voltage is adjusted by the voltage value adjustment circuit, so that the adjustment value of the peak output is met. The ON time is adjusted and set by the ON time adjusting circuit, and the waveform of the applied voltage is formed based on the ON time by the applied voltage control circuit.
For this reason, the applied voltage is formed in a waveform that reflects both the adjusted peak output and the ON time.
Therefore, when the microwave power supply device of the present invention is used for plasma CVD, a higher quality thin film can be formed as compared with the conventional microwave power supply device which is adjusted only for the ON time. Can do.

  Moreover, when the peak output of the applied voltage is adjusted high by the voltage value adjusting circuit, the ON time is adjusted to be short by the ON time adjusting circuit, while when the peak output of the applied voltage is adjusted low by the voltage value adjusting circuit, If the ON time is adjusted to be long by the ON time adjusting circuit, both the barrier properties and the adhesiveness of the thin film formed in the plasma CVD can be improved.

Furthermore, in the initial stage of plasma CVD thin film deposition, the output intensity of the applied voltage can be increased, thereby shortening the ON time, so that each performance (barrier property and adhesion) of the thin film can be improved and the light emission of the plasma. Can also be increased.
In addition, in the initial stage, the ON time can be shortened while increasing the microwave output intensity, and the high output time in the high output stage can be shortened (FIG. 24 (4)), which is necessary for the entire thin film formation by plasma CVD. Time can be shortened.

According to a fifth aspect of the present invention, the voltage value adjustment circuit includes a transformer and / or a slidac that adjusts the peak output of the applied voltage.
If the microwave power supply device has such a configuration, a transformer or a slidac that is easy to operate is used for the voltage value adjustment circuit, so that the peak output of the applied voltage can be adjusted easily and quickly.

  The microwave power supply device according to claim 6, wherein the ON time adjusting circuit adjusts the ON time of the applied voltage based on the peak output of the applied voltage determined by the voltage value adjusting circuit; A trigger generation unit that determines a trigger generation timing based on the ON time from the ON time adjustment unit, and the applied voltage control circuit includes a phase control unit that performs phase control of the applied voltage based on the trigger generation timing. It is as a configuration.

  If the microwave power supply device has such a configuration, in the microwave power supply device adopting the iron transformer system, the trigger generation timing is determined based on the set peak output, and the phase control of the applied voltage is performed by this trigger. Therefore, by adjusting the peak output to an appropriate value, it is possible to appropriately adjust the ON time of the applied voltage in conjunction with the peak output.

In particular, if the peak output is adjusted high, the ON time can be shortened, and if the peak output is adjusted low, the ON time can be lengthened, thereby providing a constant power to the microwave generator while providing a constant power. And an applied voltage in which the ON time is adjusted can be supplied.
Therefore, it is possible to improve each performance (barrier property and adhesion) of the thin film while preventing the thin film from being deformed due to excessive supply power.

  According to a seventh aspect of the present invention, the microwave power supply device includes a feedback unit that receives an applied voltage applied to the microwave generation unit as a feedback voltage, and the ON time adjusting unit of the ON time adjusting circuit is fed back from the feedback unit. The ON time is adjusted based on the voltage.

When the microwave power supply device has such a configuration, the applied voltage whose peak output (maximum voltage value) is adjusted by the voltage value adjusting circuit is sent to the ON time adjusting unit by the feedback unit, and the ON time adjusting unit Since the ON time of the applied voltage is set based on the feedback voltage, the ON time adjustment unit adjusts the ON time according to the adjusted peak output by adjusting the peak output of the fed back voltage with the voltage value adjustment unit. Can be set.
In the applied voltage control circuit, since the waveform of the applied voltage is formed based on the adjusted peak output and ON time, the microwave output reflecting the peak output and ON time is converted into the microwave. It can be generated in the generator.
Therefore, since the microwave power supply device of the present invention can adjust not only the ON time but also the peak output for the voltage applied to the microwave generator, compared to the conventional microwave power supply device, A thin film having better barrier properties and adhesion can be formed.

Further, in the microwave power supply device according to claim 8, the ON time adjustment circuit has an output setting device for setting the voltage value of the applied voltage, and the ON time adjusting unit is based on the voltage value from the output setting device. The ON time is adjusted.
If the microwave power supply device has such a configuration, the voltage value of the applied voltage can also be set by the output setting device. The ON time adjusting unit automatically determines the ON time of the applied voltage according to the voltage value set by the output setting device, and the trigger generating unit generates a trigger according to the determined ON time. The applied voltage control circuit can phase control the applied voltage according to the trigger generation timing.
Therefore, by varying the voltage value of the applied voltage with the output setting device, the waveform of the applied voltage can be formed based on this voltage value.

  The microwave power supply device according to claim 9, wherein the trigger generation unit includes a pulse transformer that generates a trigger, and the ON time adjustment unit includes a feedback voltage from the feedback unit and / or a voltage value from the output setting device. On the basis of the above, a diode bridge for determining the ON time and a capacitor for applying a voltage indicating a constant value to the trigger generation unit are provided.

  When the microwave power supply device has such a configuration, the diode bridge determines the ON time based on the feedback voltage from the feedback unit or the voltage value from the output setting device, and the capacitor has a voltage indicating a constant value at the trigger generation unit. Therefore, the trigger generation unit may output a voltage (trigger) whose phase (generation timing) is determined according to the ON time determined by the diode bridge and whose voltage value is constant on the output side. it can. Thereby, the applied voltage control circuit can phase-control the applied voltage according to the trigger whose generation timing is determined based on the adjusted peak output.

In this way, by adjusting the peak output of the applied voltage by the voltage value adjustment circuit, the ON time can be adjusted according to the peak output, so the waveform of the applied voltage based on both the peak output and the ON time. Can be formed.
Therefore, since the microwave is output from the microwave generating portion by the applied voltage in which both the peak output and the ON time are adjusted, it is possible to form a thin film with good barrier properties and adhesion.

In the microwave power supply device according to the tenth aspect, the phase control unit includes a triac that controls the phase of the applied voltage based on the trigger signal.
If the microwave power supply device has such a configuration, phase control can be performed on both positive and negative waveforms of the AC sine waveform. For this reason, even if an applied voltage control circuit using a triac is provided between the AC power supply and the transformer circuit (or between the AC power supply and the rectifier circuit), the phase-controlled applied voltage is applied to the microwave generator. The desired microwave can be generated.

The microwave power supply device according to claim 11 includes a switching regulator that stabilizes an alternating voltage applied as a power supply voltage to a predetermined voltage.
If the microwave power supply device has such a configuration, the voltage applied to the microwave generator can be stabilized even when the power supply voltage fluctuates, and stable plasma can be generated in the chamber. . In addition, since the switching regulator has a high response speed and a small amount of ripple, it can always generate a constant and stable plasma.

The microwave power supply device according to a twelfth aspect has a heater voltage stabilization circuit that stabilizes the heater voltage of the microwave generation unit.
When the microwave power supply device has such a configuration, the heating state of the heater of the microwave generation unit is stabilized, and a preheating state in which electrons can be stably emitted can be obtained. Thereby, stable plasma can be generated in the chamber.

According to the present invention, the waveform of the applied voltage can be formed based on each of the voltage setting value set by the voltage value adjusting circuit and the ON time set by the ON time adjusting circuit. One or both of the ON times can be adjusted to control the microwave output emitted from the microwave generator.
Therefore, in the initial stage, for example, the ON time is shortened while increasing the voltage set value, and in the high output stage, the ON time is lengthened while increasing the voltage set value. ) Can be formed.

In addition, since the ON time of the applied voltage can be shortened while increasing the output intensity of the microwave, it is possible to improve the light emission of plasma in the process chamber.
Further, as the ON time in the initial stage is shortened, the high output time in the high output stage can be shortened, so that the time required for the entire thin film formation by plasma CVD can be shortened.
In addition, by providing a switching regulator that stabilizes the AC voltage to the desired voltage and a stabilization circuit that stabilizes the heater voltage of the microwave generator, stable plasma can be generated in the chamber even if the power supply voltage fluctuates. Can be generated.

Hereinafter, a preferred embodiment of a microwave power supply device of the present invention will be described with reference to the drawings.
[First embodiment]
First, the whole structure of the microwave power supply device concerning 1st embodiment of this invention is demonstrated with reference to FIG.
FIG. 2 is a block diagram showing a circuit configuration of the microwave power supply device of this embodiment.

As shown in the figure, the microwave power supply device 1 includes an AC power supply 11, a voltage value adjustment circuit 12, a voltage value setting unit 12-1, an applied voltage control circuit 13, a transformer circuit 14, and a rectifier circuit 15. And a drive circuit 16, a microwave generator 17, a feedback circuit 18, and an ON time adjustment circuit 19.
The AC power supply 11 is a commercial power supply of 200 [V] (or 100 [V]). In addition, the storage battery of the same voltage can also be used. In this case, a smoothing circuit is unnecessary.

The voltage value adjustment circuit 12 is a voltage variable circuit for adjusting the power supply voltage supplied from the AC power supply 11 to an arbitrary voltage value by a user's operation and supplying it to the applied voltage control circuit 13, for example, A transformer, a slider or the like can be used.
Moreover, it can be adjusted to an arbitrary voltage value by an external signal. For example, the voltage is switched to be high when the output is low and to be low when the output is high.

The voltage value setting unit 12-1 sets the maximum voltage value (peak voltage) of the voltage adjusted by the voltage value adjustment circuit 12.
The applied voltage control circuit 13 is based on the maximum voltage value (peak voltage) of the applied voltage determined by the voltage value adjustment circuit 12 and the ON time (voltage application time) determined by the ON time adjustment circuit 19. A waveform of the voltage applied to the wave generator 17 is formed.

The transformer circuit 14 has a step-up transformer, and boosts the voltage sent from the applied voltage control circuit 13.
The rectifier circuit 15 performs full-wave rectification on the high voltage boosted by the transformer circuit 14.
The drive circuit 16 applies the high voltage rectified voltage from the rectifier circuit 15 to the microwave generator 17 to drive the microwave generator 17. In the present embodiment, the voltage applied to the microwave generator 17 is referred to as an applied voltage.

The microwave generator 17 generates a microwave based on the waveform of the applied voltage (maximum voltage value and ON time).
The feedback circuit 18 sends the voltage received from the rectifier circuit 15 to the ON time adjustment circuit 19. That is, the feedback circuit 18 sends a voltage corresponding to the voltage applied to the microwave generation unit 17 to the ON time adjustment circuit 19.
The ON time adjusting circuit 19 determines a predetermined time (for example, a predetermined signal) to the applied voltage control circuit 13 based on the voltage from the feedback circuit 18 in order to determine the ON time of the applied voltage applied to the microwave generator 17. (Or a trigger or the like with timing) is sent (or the operation of the applied voltage control circuit 13 is controlled).

If the microwave power supply device has such a configuration, the voltage applied to the microwave generation unit is adjusted based on the voltage value set by the voltage value adjustment circuit and the ON time determined by the ON time adjustment circuit. Can be controlled.
Therefore, it is possible to change the output intensity of the microwave emitted from the microwave generation unit, and it is possible to form a thin film that is excellent in both barrier properties and adhesion.

In FIG. 1, the arrangement order of each component from the AC power supply 11 to the microwave generator 18 is “AC power supply 11” → “voltage value adjustment circuit 12” → “applied voltage control circuit 13” → “transformer circuit”. 14 ”→“ rectifier circuit 15 ”→“ drive circuit 16 ”→“ microwave generator 17 ”. However, the arrangement order is not limited to this. For example,“ AC power supply 11 ”→“ voltage value adjustment ” Circuit 12 ”→“ transformer circuit 14 ”→“ applied voltage control circuit 13 ”→“ rectifier circuit 15 ”→“ drive circuit 16 ”→“ microwave generator 17 ”or“ AC power supply 11 ”→“ voltage value adjustment circuit ” 12 ”→“ transformer circuit 14 ”→“ rectifier circuit 15 ”→“ applied voltage control circuit 13 ”→“ drive circuit 16 ”→“ microwave generator 17 ”or“ AC power supply 11 ”→“ voltage value adjustment circuit ” 12 ”→“ Applied voltage control circuit 13 ”→ Rectifier circuit 15 "→" transformer circuit 14 "→" drive circuit 16 "→ can also be adapted such as" microwave generation part 17 ".
However, the arrangement order of the components from the AC power source 11 to the microwave generator 17 can generate microwaves from the microwave generator 17 and adjust the applied voltage of the microwave generator 17. It is necessary to have a configuration that can also be performed.

Next, a specific circuit configuration of the microwave power supply device of the present embodiment will be described with reference to FIG.
In the figure, a voltage value adjustment circuit, a feedback circuit, an ON time adjustment circuit, an applied voltage control circuit, etc. are provided in a circuit that generates a microwave by applying a voltage to a microwave generation unit (magnetron) by an iron transformer method. It is an electric circuit diagram which shows the circuit structure of a microwave power supply device.

  As shown in the figure, the microwave power supply device 1 includes an AC power supply 11, a voltage value adjustment circuit 12, a voltage value setting unit 12-1, an SCR phase control unit 13-1, and a high voltage transformer 14-1. The high voltage rectifier 15-1, the heater transformer 16-1, the magnetron 17-1, the feedback unit 18-1, and the trigger forming circuit 19-1.

The voltage value adjustment circuit 12 is a device (or apparatus, circuit, device, etc.) that can convert the power supply voltage sent from the AC power supply 11 into an arbitrary voltage value. A variable slidac (for example, a slidac that can change the input voltage 200V from 0V to 220V by inputting 0V to 5V) can be used (slidac system, transformer system).
For this reason, the voltage value setting unit 12-1 has a function of adjusting the maximum voltage value (peak voltage) of the applied voltage and a function of forming the applied voltage so as to be the adjusted maximum voltage value. Yes.
The voltage value setting unit 12-1 sets the maximum voltage value (peak voltage) of the power supply voltage adjusted by the voltage value adjustment circuit 12.

  The SCR phase control unit (phase control unit) 13-1 is configured by a circuit combining two thyristors (or a circuit including a triac), and is a sine wave AC voltage supplied from the voltage value adjustment circuit 12. Perform phase control. This phase control will be described in detail later in “How the applied voltage is adjusted and controlled in the microwave power supply device of this embodiment”.

The high voltage transformer 14-1 boosts the AC voltage phase-controlled by the SCR phase control unit 13-1.
The high voltage rectifier 15-1 performs full-wave rectification on the voltage boosted by the high voltage transformer 14-1, and applies it to the anode of the magnetron 17-1. Since the voltage output from the high voltage rectifier 15-1 is applied to the magnetron 17-1 and the magnetron 17-1 is driven, the high voltage rectifier 15-1 has a function as the drive circuit 17. doing.

  The heater transformer 16-1 supplies electric power to a heater (not shown) of the magnetron 17-1, and side-heats the cathode (cathode filament of the magnetron 17-1). As a result, the magnetron 17-1 can easily emit electrons.

The magnetron 17-1 emits microwaves based on the peak voltage of the applied voltage from the high voltage rectifier 15-1 and the ON time.
The following phenomenon occurs inside the magnetron 17-1.
When the applied voltage is less than the predetermined voltage value (cut-off voltage), microwaves are not generated with high resistance. However, when the applied voltage is higher than the cut-off voltage, the resistance is low and electrons irradiated from the cathode reach the anode. Then, a closed loop is formed together with other circuits (for example, a high voltage circuit and a secondary winding), and a magnetron current (anode current) is passed between the anode and the cathode. At this time, the electric power generated in the magnetron 17-1 is converted into a microwave with a certain conversion efficiency and radiated.

The feedback unit 18-1 receives a voltage having the same value as the voltage applied to the magnetron 17-1 from the high voltage rectifier 15-1.
In FIG. 2, the feedback unit 18-1 receives the voltage from the high voltage rectifier 15-1, but is not limited to the high voltage rectifier 15-1. For example, the feedback unit 18-1 receives the voltage from the vicinity of the anode of the magnetron 17-1. You may make it receive.

As shown in FIG. 3, the trigger forming circuit 19-1 includes an output setting unit 19-11, an amplifier 19-12, and a Toulon circuit 19-13.
The output setting unit 19-11 has, for example, a voltage supply source such as a variable voltage source and a variable capacitor. By changing the value of the voltage output from these voltage supply sources, the application of the magnetron 17-1 is performed. The voltage ON time (and hence the power supplied to the magnetron 17-1) is adjusted.
The amplifier 19-12 amplifies the voltage indicating the constant value sent from the feedback unit 18-1 and the voltage value set by the output setting unit 19-11, and supplies the amplified voltage to the Toulon circuit 19-13.

The Toulon circuit 19-13 includes a diode bridge 19-14, a transformer 19-15, a capacitor 19-16, and a pulse transformer 19-17.
The diode bridge 19-14 constitutes a bridge by four diodes (D1, D2, D3, D4). These four diodes are P1 (connection point between D1 cathode and D2 cathode), P2 (connection point between D2 anode and D3 cathode), P3 (connection point between D3 anode and D4 anode). , P4 (connection point between the cathode of D4 and the anode of D1).

（以下、「ベクトルＶ_Ｒ」という）が発生する。
なお、本実施形態においては、ダイオードブリッジ１９−１４とコンデンサ１９−１６とを総称して「ＯＮ時間調整部」という。 Among these connection points, a voltage from the amplifier 19-12 is received between P1 and P3, and this voltage causes a voltage between P2 and P4.

(Hereinafter referred to as “vector V _R ”).
In the present embodiment, the diode bridge 19-14 and the capacitor 19-16 are collectively referred to as an “ON time adjusting unit”.

（以下、「ベクトルＶ_Ｃ」という）が、それぞれ発生する。
パルストランス（トリガ発生部）１９−１７は、トリガを発生して、ＳＣＲ位相制御部１３−１へ与える。 The transformer 19-15 transforms the power supply voltage and applies the transformed voltage to the diode bridge 19-14 and the capacitor 19-16. Thus, the vector _{V R} is between P2-P4 of the diode bridge 19-14 is, in the capacitor 19-16 Voltage

(Hereinafter referred to as “vector V _C ”).
The pulse transformer (trigger generation unit) 19-17 generates a trigger and supplies it to the SCR phase control unit 13-1.

（以下、「ベクトルＶ_Ｓ」という）が加わる。
そうすると、ダイオードブリッジ１９−１４にはベクトルＶ_Ｒが、コンデンサ１９−１６にはベクトルＶ_Ｃがそれぞれ発生するが、これらは図４に示すように、位相が９０°ずれる（ベクトルＶ_ＲがベクトルＶ_Ｃよりも９０°遅れる）とともに、それらを合成するとベクトルＶ_Ｓとなる（ベクトルＶ_Ｒ＋ベクトルＶ_Ｃ＝ベクトルＶ_Ｓ）。 The relationship between the voltages of the components of the Toulon circuit 19-13 is as follows.
The diode bridge 19-14 and the capacitor 19-16 are connected in series to the transformer 19-15. The transformer 19-15 is connected to both ends of the diode bridge 19-14 and the capacitor 19-16 connected in series. Secondary voltage

(Hereinafter referred to as “vector V _S ”).
Then, the vector _{V R} is the diode bridge 19-14 is, although the capacitor 19-16 respectively generate the vector _{V C,} which are shown in FIG. 4, the phase is shifted 90 ° (vector _{V R} is the vector V _When they are combined, a vector V _S is obtained (vector V _R + vector V _C = vector V _S ).

（以下、「ベクトルＶ_Ｎ」という）は、このベクトルＶ_Ｎのベクトルの始点がベクトルＶ_Ｓを二等分した点に位置する。 In contrast, the pulse transformer 19-17 is connected in parallel to the diode bridge 19-14 and the capacitor 19-16, and one end of the pulse transformer 19-17 is connected to the secondary side of the transformer 19-15. Connected in the middle of the winding.
From this, the voltage generated in the pulse transformer 19-17

(Hereinafter, referred to as "vector V _N"), the starting point of the vector of the vector V _N is located in that bisects the vector V _S.

Further, since it has a phase difference of one another 90 ° to the vector V _R and the vector V _C, the starting point of the vector V _R is located at the beginning of the vector V _S, the end point of the vector V _C is a vector V _S When to be positioned at the end point, the end point and the vector V _C of the start point and overlap point P _RC of the vector V _R is located somewhere on the circumference of the semicircle diameter vector V _S.
In the vector V _N generated in the pulse transformer 19-17, the end point of the vector V _N is located at the point P _RC .

Furthermore, the vector _{V R,} although its value by the voltage from the amplifier 19-12 is changed, thereby, the point _{P RC} moves on a circumference of a semicircle diameter vector _{V S.} Along with this movement, the vector V _N has a constant magnitude, and the phase changes from 0 ° to nearly 180 °.
In this case, timing of the trigger generated from the pulse transformer 19-17 is according to the phase of the vector _{V N.} For this reason, the Toulon circuit 19-13 can determine the trigger generation timing based on the voltage value set by the output setting unit 19-11 and the voltage value from the feedback unit 18-1.

In the SCR phase control unit (phase control unit) 13-1, the AC voltage from the voltage value adjustment circuit 12 is phase-controlled by receiving triggers from the pulse transformer 19-17 at the gates and cathodes of the two thyristors, respectively. can do.
In FIG. 2, two thyristors are used, but a triac can be used instead of the two thyristors.

Next, how the applied voltage is adjusted and controlled in the microwave power supply device of the present embodiment will be described with reference to FIG.
As shown in the figure, it is assumed that the power supply voltage of the AC power supply 11 is an AC sine wave voltage indicating a maximum voltage (peak voltage) of 200 [V].

The power supply voltage indicating 200 [V] is set / adjusted to an arbitrary voltage value by the voltage value adjustment circuit 12. For example, if the voltage value setting unit 12-1 is set to 180 [V], the power supply voltage indicating 200 [V] is changed to 180 [V] by the voltage value adjusting circuit 12 as shown in FIG. Adjusted.
The voltage adjustment in the voltage value adjusting circuit 12 can be adjusted differently during coating, at low output and at high output. For example, it can be set and adjusted to 205 [V] at low output, and can be set and adjusted to 165 [V] at high output.

As described above, the voltage value adjustment circuit 12 can adjust the voltage value of the power supply voltage, whereby the peak voltage of the voltage applied to the magnetron 17-1 can be adjusted.
In addition, in the thin film formation process, it is possible to adjust the voltage value (adjustment of the maximum voltage value (peak voltage) of the applied voltage) different between the low output and the high output. The microwave output can be changed differently between the low output and the high output.
However, voltage adjustment is not performed here, and the secondary side voltage of the voltage value adjustment circuit 12 indicates a maximum voltage value of 200 [V].

Next, the AC voltage from the voltage value adjusting circuit 12 is phase-controlled by the SCR phase control unit 13-1, and has a waveform as shown in FIG.
When this phase-controlled AC voltage is boosted by the high-voltage transformer 14-1 and full-wave rectified by the high-voltage rectifier 15-1, a phase-controlled full-wave rectified waveform is obtained as shown in FIG.
The voltage (applied voltage) formed in the phase-controlled full-wave rectified waveform is applied to the anode of the magnetron 17-1. Then, the cathode is heated by the heater transformer 16-1, whereby microwaves are emitted from the magnetron 17-1.

By the way, a voltage having the same value as the voltage applied to the magnetron 17-1 is taken into the trigger forming circuit 19-1 from the high voltage rectifier 15-1 via the feedback unit 18-1. In the output setting unit 19-11, a certain ON time is set.
The voltage from the feedback unit 18-1 and the voltage from the output setting unit 19-11 are amplified by the amplifier 19-12 and applied to the diode bridge 19-14 of the Toulon circuit 19-13.

The application of this amplified voltage, vector V _R of the diode bridge 19-14 indicates a value corresponding to the voltage value thereof applied.
Here, for example, when the absolute value of the vector _{V R} of the diode bridge 19-14 is to become larger than the absolute value of the vector _{V C} of the capacitor 19-16 (FIG. 9 (a)), the trigger forming circuit 19-1 The generated trigger depends on the phase of the vector V _N of the pulse transformer 19-17 (the vector V _N is the upper half starting from the midpoint of the vector V _{S in} the vertical bisector of the vector V _S (see FIG. This occurs at a point in time when the peak of the sine waveform indicated by the power supply voltage has passed a little (see (b) in the figure).

When this trigger occurs, the SCR phase control unit 13-1 operates and the phase of the power supply voltage from the voltage value adjustment circuit 12 is controlled.
Then, the boosted and rectified applied voltage is formed into a waveform as shown in FIG. 9B, and is applied to the magnetron 17-1, and microwave output is started.
In the above description, the setting of the output setting unit 19-11 is kept constant. However, by adjusting this output setting unit 19-11, the ON time at the same maximum voltage is adjusted, and the magnetron 17- The power of the applied voltage given to 1 can be adjusted.

On the other hand, as shown in FIG. 6, when the power supply voltage of the AC power supply 11 showing the maximum voltage value of 200 [V] is set a little lower by the voltage value setting unit 12-1 (for example, 180 [V]) When the set value of the output setting device 19-11 is constant, the voltage applied to the diode bridge 19-14 of the Toulon circuit 19-13 also changes, so that the diode bridge 19- 14 vector _{V R} also changes the.
This varies with when the absolute value of the vector _{V R} becomes smaller than the absolute value of the vector _{V C} of the capacitor 19-16 (FIG. 10 (a)), a trigger generated by the trigger forming circuit 19-1, a pulse transformer 19 According to the phase of the vector V _N of −17 (the vector V _N is delayed from the upper half (not shown) starting from the midpoint of the vector V _{S in} the vertical bisector of the vector V _S For this reason, it occurs at a point just before the peak of the sine waveform indicated by the power supply voltage (see FIG. 5B).

When this trigger occurs, the SCR phase control unit 13-1 operates and the phase of the power supply voltage from the voltage value setting unit 12-1 is controlled.
Then, the boosted and rectified applied voltage is formed into a waveform as shown in FIG. 10B, and is applied to the magnetron 17-1, and microwave output is started.

Here, comparing FIG. 9B and FIG. 10B, if the output setting is constant when there is feedback, the generation timing of each trigger is different, but is given to the magnetron 17-1 (the waveform of each waveform). The power is the same.
That is, even if the power supply voltage is set to 200 [V] or 180 [V] by the voltage value setting unit 12-1, the power supplied to the magnetron 17-1 is constant.

In other words, in addition to changing the output setting, the maximum voltage value of the power supply voltage is set and adjusted by the voltage value setting unit 12-1 and the voltage value adjusting circuit 12, so that the magnetron 17-1 has the maximum voltage. Applied voltage having a high ON time and a short ON time (waveform as shown in FIG. 9B), and conversely, an applied voltage having a low maximum voltage value and a long ON time (waveform as shown in FIG. 10B) is given. It becomes possible.
That is, when the output is low, the output setting is lowered, and the power supply voltage is increased by the voltage value setting unit 12-1, whereby a pulse application voltage with a shorter ON time and a high peak output can be obtained. Further, at the time of high output, by increasing the output setting and further lowering the power supply voltage by the voltage value setting unit 12-1, a pulse application voltage having a long ON time and a high peak output can be obtained.
Then, by the microwave output emitted from the magnetron 17-1, adjusted as described above, as shown in FIG. 21 (3), a thin film having good barrier properties and adhesion is formed. Can do.

As described above, the microwave power supply device according to the present embodiment is adjusted only by the voltage value setting unit, so that the power applied to the magnetron is kept constant, and the applied voltage with a high maximum voltage value and a short ON time is maintained. An applied voltage having a large average output and a long ON time can be applied. Then, by adjusting both the voltage value setting unit and the output setting unit, the waveform of the voltage applied to the magnetron can be adjusted to a desired shape.
Therefore, the microwave power supply device of this embodiment can adjust the output intensity of the microwave according to the property of the object (substrate) of thin film deposition, and forms a thin film excellent in both barrier properties and adhesion. Make it possible.

[Second Embodiment]
Next, a second embodiment of the microwave power supply device of the present invention will be described with reference to FIG.
FIG. 2 is a block diagram showing the configuration of the microwave power supply device of this embodiment.
This embodiment differs from the first embodiment in the conversion method of the applied voltage of the microwave power supply device. That is, in the first embodiment, the conversion method of the applied voltage is an iron transformer method, whereas in this embodiment, the conversion method is an inverter method. Other components are the same as those in the first embodiment.
Therefore, in FIG. 11, the same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

As illustrated in FIG. 11, the microwave power supply device 1 includes an AC power supply 11, a rectifier circuit 15, a smoothing circuit 20, an inverter circuit unit 21, a transformer circuit 14, a voltage doubler rectifying and smoothing circuit 22, and a microwave. The generator 17, the voltage value adjustment circuit 23, the ON time adjustment circuit 24, and the inverter drive circuit unit 25 are included.
In the present embodiment, the inverter circuit unit 21 and the inverter drive circuit unit 25 are collectively referred to as “applied voltage control circuit VC”.

Here, the rectifier circuit 15 performs full-wave rectification on the power supply voltage from the AC power supply 11.
The smoothing circuit 20 is composed of a capacitor, a resistor, a choke coil, and the like, and removes the ripple of the voltage rectified by the rectifier circuit 15.
The inverter circuit unit 21 includes a switching element 21-1, and the voltage from the smoothing circuit 20 is intermittently controlled according to the applied voltage adjustment wave from the inverter drive circuit unit 25 (usually the inverter frequency is , 20 kHz or more).

The waveform intermittently controlled by the inverter circuit unit 21 is shown in FIG.
As shown in the figure, among the waveforms generated by the inverter circuit unit 21, the time during which the high frequency voltage is generated is referred to as "ON time", and the time during which the high frequency voltage is not generated is referred to as "OFF time". That's it.
And the high frequency voltage which generate | occur | produced in ON time is generate | occur | produced intermittently as each pulse.
The length of the ON time, the length of the OFF time, and the frequency of the high frequency voltage in the ON time of the intermittently controlled high frequency voltage generated in the inverter circuit unit 21 are controlled by the inverter drive circuit 25.

The transformer circuit 14 includes a step-up transformer and the like, and boosts the high-frequency voltage from the inverter circuit unit 21.
For example, a high voltage winding or a cathode heating winding can be provided on the secondary side of the transformer circuit 14 (the high voltage winding or the cathode heating winding is not shown).

The voltage doubler rectifying / smoothing circuit 22 includes a high voltage capacitor, a high voltage diode, and the like.
Among these, the high voltage capacitor is charged by the reverse high voltage appearing in the secondary high voltage winding of the transformer circuit 14 during the OFF time of the switching element 21-1 of the inverter circuit unit 21.
The voltage charged in the high-voltage capacitor is added in series with the high voltage appearing in the secondary high-voltage winding of the transformer circuit 14 during the ON time of the switching element 21-1, and a microwave generator (for example, a magnetron) Applied to 17 anodes.

The voltage value adjustment circuit 23 inputs a voltage setting value (peak voltage value) of the applied voltage from the outside. The voltage value adjustment circuit 23 can also receive the voltage applied to the microwave generation unit 17 from the voltage doubler rectification circuit 22. That is, the voltage value adjusting circuit 23 determines the peak voltage value (or the peak voltage of the applied voltage from the voltage doubler rectifier circuit 22) inputted externally as the peak voltage of the applied voltage.
The ON time adjustment circuit 24 inputs the ON time of the applied voltage from the outside. That is, the ON time adjustment circuit 24 determines the externally input ON time as the ON time of the applied voltage.

  The inverter drive circuit unit 25 adjusts the waveform of the applied voltage based on the voltage setting value of the applied voltage input by the voltage value adjusting circuit 23 and the ON time of the applied voltage input by the ON time adjusting circuit 24. The signal (applied voltage adjustment wave) is formed, and the switching element 21-1 of the inverter circuit unit 21 is driven and controlled in accordance with the applied voltage adjustment wave.

If the microwave power supply device has such a configuration, a micro power supply is set based on the voltage setting value (peak voltage) of the applied voltage set by the voltage value adjusting circuit and the ON time of the applied voltage set by the ON time adjusting circuit. The output intensity of the microwave emitted from the wave generator can be changed.
Therefore, by setting the peak voltage of the applied voltage and the ON time to appropriate values, a microwave that makes both the barrier property and adhesion of the thin film formed on the substrate benign during CVD deposition is micronized. It can be output to the wave generator.

Next, a specific circuit configuration of the microwave power supply device of the present embodiment will be described with reference to FIG.
As shown in the figure, the microwave power supply device 1 of this embodiment includes a three-phase AC power supply 11-1, a three-phase rectifier 15-2, a smoothing circuit 20, a half-bridge inverter 21-1, and a transformer 14. -2, voltage doubler rectifying and smoothing circuit 22, magnetron 17-1, output variable input 23-1, pulse width variable input 24-1, setting variable control circuit 25-1, and gate drive circuit 25-2. And have.

The three-phase rectifier 15-2 converts the three-phase AC voltage from the three-phase AC power source 11-1 into a DC voltage.
In FIG. 13, the three-phase AC power source 11-1 is used as the power source, but is not limited to the three-phase AC power source, and may be a two-phase AC power source, for example.

  The half-bridge inverter 21-1 includes a transistor 21-11 (for example, an insulated gate bipolar transistor (IGBT), a bipolar junction transistor (BJT), a MOS field effect transistor (MOSFET), etc.) as a switching element, and a diode 21-12. And a capacitor 21-13 is provided.

The transistor 21-11 has a gate connected to the gate drive circuit 25-2, and the drive control of the gate drive circuit 25-2 converts the DC voltage from the smoothing circuit 20 into an intermittent high-frequency voltage (FIG. 12). Convert. This converted intermittent high-frequency voltage is applied to the primary side winding of the transformer 14-2.
In the present embodiment, two transistors 21-11 (transistor 21-11a and transistor 21-11b) are provided.

The transformer (inverter transformer) 14-2 boosts the high-frequency voltage from the half-bridge inverter 21-1, and supplies it to the voltage doubler rectifying / smoothing circuit 22 as a high-frequency high-voltage.
The voltage doubler rectifying and smoothing circuit 22 includes a high voltage capacitor 22-1 and a high voltage diode 22-2, and the reverse voltage that appears in the secondary high voltage winding of the transformer 14-2 during the OFF time of the switching element of the inverter circuit 21. The high voltage capacitor 22-1 is charged by the high voltage in the direction. The voltage charged in the high voltage capacitor 22-1 is added in series to the high voltage appearing in the secondary high voltage winding during the ON time of the switching element, and is applied to the anode of the magnetron 17-1.

The output variable input 23-1 is a variable device (for example, a variable resistor, an external control signal, etc.) provided for adjusting the peak voltage value (voltage set value) of the voltage applied to the magnetron 17-1. Then, a signal indicating the adjustment value of the peak voltage (output control signal) is sent to the setting variable control circuit 25-1.
The pulse width variable input 24-1 is a variable device (for example, a variable resistor, an external control signal, etc.) provided for adjusting the pulse width (ON time) of the voltage applied to the magnetron 17-1. Then, a signal indicating the adjustment value of the pulse width (oscillation time control signal) is sent to the setting variable control circuit 25-1.

The setting variable control circuit (setting variable control unit) 25-1 receives the voltage setting value from the output variable input 23-1, and the ON time setting value from the pulse width variable input 24-1, and receives the gate driving circuit 25- Send to 2.
Specifically, as shown in FIG. 14, the setting variable control circuit 25-1 includes a sawtooth wave generator 25-11, a comparator E25-12, an overcurrent detection 25-13, and an oscillation stop circuit 25-. 14, an oscillation permission signal input 25-15, and a heater timer 25-16.

The sawtooth generator 25-11 generates a sawtooth wave with a predetermined cycle time.
The comparator E25-12 applies PWM (Pulse Width Modulation) to the sawtooth wave input from the sawtooth wave generator 25-11 based on the pulse width adjustment value (oscillation time control signal) input from the pulse width variable input 24-1. (Pulse width modulation) is performed, and this waveform (oscillation stop signal) is sent to the oscillation stop circuit 25-14.
The overcurrent detection 25-13 receives the voltage (applied voltage) applied to the magnetron 17-1 from the voltage doubler rectifying and smoothing circuit 22, determines whether or not the received applied voltage is an overcurrent, and the result of this determination (Overcurrent detection signal) is sent to the oscillation stop circuit 25-14.

The oscillation stop circuit 25-14 sends the output control signal input from the output variable input 23-1 to the second comparator A25-24a and the second comparator B25-24b.
The oscillation stop circuit 25-14 forcibly sets the output control signal to 0 [V] when the oscillation stop signal from the comparator E25-12 indicates "0".
The oscillation stop signal 25-17 includes the sawtooth wave with PWM input from the comparator E25-12, the overcurrent detection signal input from the overcurrent detection 25-13, and the oscillation enable signal input 25-15. The oscillation permission signal input from the heater 25, the signal input from the heater timer 25-16, and the like are included.

The gate drive circuit (switching element drive unit) 25-2 drives the transistor (IGBT) 21-11 of the half-bridge inverter 21-1 based on the output control signal from the setting variable control circuit 25-1. Further, the gate drive circuit 25-2 does not drive the transistor (IGBT) 21-11 when the output control signal is not sent from the setting variable control circuit 25-1.
In the present embodiment, the setting variable control circuit 25-1 and the gate drive circuit 25-2 are collectively referred to as “inverter drive circuit unit 25”.

  Here, specifically, as shown in FIG. 14, the gate drive circuit 25-2 includes a triangular wave generator 25-21, a first comparator A25-22a, a first comparator B25-22b, and a saw. Wave shaper A25-23a, sawtooth wave shaper B25-23b, second comparator A25-24a, second comparator B25-24b, IGBT driver A25-25a, and IGBT driver B25-25b doing.

The triangular wave generator 25-21 generates a triangular wave (waveform A) (FIG. 15 (a)).
The first comparator A25-22a compares the triangular wave generated by the triangular wave generator 25-21 with a predetermined threshold (comparison voltage A) (comparison A), and when the triangular wave shows a value equal to or lower than the threshold. A square wave (waveform B) is generated (FIG. 15B).
The first comparator B25-22b compares the triangular wave generated by the triangular wave generator 25-21 with a threshold value (comparison voltage B set to a value lower than the comparison voltage A) (comparison B), and the triangular wave is the threshold value. When the above values are shown, a square wave (waveform C) is generated (FIG. 15C).

The sawtooth wave shaper A25-23a shapes and outputs a sawtooth wave to the square wave generated by the first comparator A25-22a (waveform D, FIG. 15 (d)).
The sawtooth wave shaper B25-23b shapes and outputs a sawtooth wave to the square wave generated by the first comparator B25-22b (waveform E, FIG. 15 (e)).

The second comparator A25-24a includes a square wave (waveform D) obtained by shaping the sawtooth wave with the sawtooth wave shaper A25-23a, and a voltage value (output control) indicated by the output control signal input from the oscillation stop circuit 25-14. When the waveform D shows a value equal to or lower than the output control voltage, a square wave (waveform F) is generated (FIG. 15 (f)).
The second comparator B25-24b is a square wave (waveform E) obtained by shaping the sawtooth wave by the sawtooth wave shaper B25-23b, and a voltage value (output control) indicated by the output control signal input from the oscillation stop circuit 25-14. When the waveform E shows a value equal to or lower than the output control voltage, a square wave (waveform G) is generated (FIG. 15 (g)).

The IGBT driver A25-25a drives the transistor (IGBT) 21-11a of the half-bridge inverter 21-1 according to the square wave (waveform F) from the second comparator A25-24a.
The IGBT driver B25-25b drives the transistor (IGBT) 21-11b of the half-bridge inverter 21-1 according to the square wave (waveform G) from the second comparator B25-24b.
The voltage applied to the inverter transformer 14-2 by driving the transistors (IGBT) 21-11a and the transistor (IGBT) 21-11b is as shown in FIG.

The comparison voltage A of the first comparator A25-22a is set to a value slightly higher than the comparison voltage B of the first comparator B25-22b. For this reason, a “deviation L” occurs when the waveform B rises and when the waveform C falls (or when the waveform B falls and when the waveform C rises). When this “deviation L” occurs, a “gap S” is formed between the waveform F output from the second comparator A25-24a and the waveform G output from the second comparator B25-24b. .
In other words, the waveform F for operating the IGBT driver A25-25a and the waveform G for operating the IGBT driver B25-25b are different at the time of waveform formation, and there is a “gap S” between the waveform F and the waveform G. is there. For this reason, the IGBT 21-11a and the IGBT 21-11b of the half-bridge inverter 20-1 are not turned ON at the same time.

The waveforms shown in FIGS. 15A to 15H are controlled from the oscillation stop circuit 25-14 of the setting variable control circuit 25-1 to the second comparator A25-24a and the second comparator B25-24b. The control is performed when an output control signal is sent.
On the other hand, when the output control signal is not sent from the oscillation stop circuit 25-14 to the second comparator A25-24a and the second comparator B25-24b (from the comparator E25-12 of the setting variable control circuit 25-1). The oscillation stop signal 25-17 sent to the oscillation stop circuit 25-14 indicates “0”), and the waveform F from the second comparator A25-24a to the IGBT driver A25-25a and the second comparator B25- Since both the waveform G from 24b to the IGBT driver B25-25b is 0 [V], no waveform is output from the IGBT 20-11, and no microwave is generated from the magnetron 17-1.

  In this way, the peak voltage of the applied voltage can be adjusted by sending the output control signal from the oscillation stop circuit 25-14 to the second comparator A25-24a and the second comparator B25-24b, and the output control signal Generation of intermittent microwaves is made possible by creating time for sending (ON time) and time for not sending (OFF time).

That is, the peak voltage of the applied voltage output from the IGBT 20-11 can be adjusted by the voltage setting value input at the output variable input 23-1. Moreover, the ON time of the applied voltage output from IGBT20-11 can be adjusted with the pulse width setting value input with the pulse width variable input 24-1.
Among these, the waveform of the applied voltage is formed as shown in FIGS. 16 and 17 when the ON time of the applied voltage is adjusted by the pulse width setting value input by the pulse width variable input 24-1.

For example, when the ON time is set short in the pulse width variable input 24-1, as shown in FIG. 16, the OFF time is long and the ON time is short.
On the other hand, when the ON time is set long in the pulse width variable input 24-1, the OFF time is short and the ON time is long as shown in FIG. In both cases, when the output variable input is changed, the voltage level changes.

  In addition, in the pulse wave of FIG. 16 or FIG. 17, the high frequency is output from the transistor 21-11 of the half bridge inverter 21-1. For this reason, the waveform shown in FIG. 16 or FIG. 17 indicates that a pulse wave formed at a high frequency is intermittently output.

  As a result, the DC voltage sent from the smoothing circuit 20 to the half-bridge inverter 21-1 is variable in the voltage setting value and pulse width input at the output variable input 23-1 by ON / OFF control of the transistor 21-11. The pulse width (ON time) input at the input 24-1 is converted into a high frequency formed into a waveform corresponding to the voltage value of the applied voltage input at the gate drive circuit (output / pulse width control circuit) 25-2. The

[Third embodiment]
Next, a third embodiment of the microwave power supply device of the present invention will be described with reference to FIG.
FIG. 2 is a block diagram showing the configuration of the microwave power supply device of this embodiment.
The present embodiment is different from the first embodiment in that a switching regulator and a heater voltage stabilization circuit are newly provided. Other components are the same as those in the first embodiment.
Therefore, in FIG. 18, the same components as those in FIG. 1 and the like are denoted by the same reference numerals, and detailed description thereof is omitted.

As shown in FIG. 18, the microwave power supply device 1 according to the present embodiment includes a switching regulator 31, a reference voltage setting unit 32, and a heater voltage stabilization circuit 40.
Here, the switching regulator 31 is a circuit that controls so that a stable output voltage can be obtained by turning on / off the digital switch and modulating the pulse width. By using such a switching regulator 31, the AC voltage supplied as the power supply voltage can be stabilized to a desired voltage and sent to the rectifier circuit 15 or the like.

The reason why the microwave power supply device of this embodiment includes AC voltage stabilization means and employs a switching regulator as the means is as follows.
The microwave power supply device is used as, for example, a magnetron drive source for supplying microwaves to a thin film deposition chamber.
However, when such a microwave power supply apparatus is not provided with means for stabilizing the microwave output, if the power supply voltage fluctuates, the microwave output fluctuates greatly accordingly. For this reason, stable plasma cannot be obtained in the chamber.

Therefore, it is necessary to provide an AC voltage stabilizing means in the microwave power supply apparatus. Furthermore, in order to form a thin film having excellent performance in the chamber, as shown in FIG. 19, in a very narrow range. It is required to stabilize the power supply voltage. Specifically, it is within a range of 200 [V] to 204 [V], and a value smaller than this is a thin film with low barrier performance, while a larger value is a film formation target (for example, a plastic bottle). Thermal deformation will occur.
In addition, if it takes time to stabilize the voltage, the performance of the deposited film is deteriorated.
Therefore, the AC voltage stabilization means provided in the microwave power supply device is required to have excellent stability and responsiveness.

Here, examples of the voltage stabilizing means include a series regulator, phase control, feedback, and switching regulator.
However, since the series regulator releases unnecessary voltage as heat, the loss is large. Further, the phase control has a drawback that the response is poor and a ripple is generated. Furthermore, since the feedback detects and feeds back the output, the response is poor, and the rising characteristic of the output is impaired, so that the performance of the deposited film is deteriorated.
Compared with these, the switching regulator has a high response speed and a small loss. Also, it has excellent output voltage stability and small ripple. In addition, it has the advantage that it can perform efficient voltage conversion with low power consumption.
Therefore, in this embodiment, a switching regulator is employed as the AC voltage stabilizing means. Thereby, even if the power supply voltage of the microwave power supply device fluctuates, stable plasma can be generated in the chamber.

If the switching frequency in the inverter circuit unit 21 is 100 [kHz], for example, the switching frequency of the switching regulator 31 can be 27 [kHz] or the like.
In addition, by providing the switching regulator 31, the power supply voltage fluctuation is ± 5 [%], the DC voltage fluctuation is ± 0.2 [%], the output fluctuation is ± 2.5 [%], etc. You can get each value you want.

The reference voltage setting unit 32 sets a voltage value that is stabilized by the switching regulator 31.
For example, 202 [V] can be set in FIG.

  The heater voltage stabilization circuit 40 can be constituted by, for example, a phase control circuit or the like, and is connected to the heater of the magnetron 17-1 via the heater transformer 40-1 as shown in FIG. Apply. Thereby, the heater can be stably heated to a predetermined temperature, and the magnetron can be in a preheated state in which electrons can be stably emitted (emission). Therefore, stable plasma can be generated in the chamber.

  The present invention is an invention relating to a power supply device capable of controlling a voltage applied to a microwave generator (magnetron), and therefore can be used as a power supply device for driving a magnetron in an apparatus using microwaves.

It is a block diagram which shows the structure of the microwave power supply device concerning 1st embodiment of this invention. FIG. 2 is an electric circuit diagram showing a specific circuit configuration of the microwave power supply device according to the first embodiment of the present invention. It is an electric circuit diagram which shows the internal structure of a trigger circuit. It is a vector diagram which shows the relationship of the voltage of each part in a Toulon circuit. It is a curve graph which shows the waveform of the alternating current power supply of the microwave power supply device shown in FIG. It is a curve graph which shows the waveform of the alternating current power supply stepped down by the voltage value adjustment circuit of the microwave power supply device shown in FIG. It is a curve graph which shows the waveform by which the AC power supply was phase-controlled by the SCR phase control part of the microwave power supply device shown in FIG. 8 is a curve graph showing a waveform obtained by full-wave rectification of the phase-controlled AC power source shown in FIG. When the phase of the voltage V _N generated in the pulse transformer of the Toulon circuit is advanced, the vector diagram (a) showing the relationship between the voltages of the respective parts in the Toulon circuit and the trigger when the relationship shown in (a) is satisfied It is a graph which shows the generation | occurrence | production timing of. When the phase of the voltage V _N generated in the pulse transformer of the Toulon circuit is delayed, the vector diagram (a) showing the relationship between the voltages of the respective parts in the Toulon circuit and the trigger when the relationship shown in (a) is satisfied It is a graph which shows the generation | occurrence | production timing of. It is a block diagram which shows the structure of the microwave power supply device concerning 2nd embodiment of this invention. It is a wave form diagram which shows the waveform of the high frequency voltage by which the inverter circuit part shown in FIG. 11 was intermittently controlled. It is an electric circuit diagram which shows the concrete circuit structure of the microwave power supply device concerning 2nd embodiment of this invention. FIG. 14 is a block diagram illustrating specific configurations of a setting variable control circuit and a gate drive circuit illustrated in FIG. 13. FIG. 15 is a waveform diagram showing waveforms output from each component in the gate drive circuit shown in FIG. 14. It is a wave form diagram which shows the waveform of the applied voltage when ON time is set short with pulse width variable input. It is a wave form diagram which shows the waveform of the applied voltage when ON time is set long with pulse width variable input. It is a block diagram which shows the structure of the microwave power supply device concerning 3rd embodiment of this invention. It is a graph which shows the appropriate range of the power supply voltage of the microwave power supply device for providing the vapor deposition film of the outstanding performance. It is an electronic circuit diagram which shows the specific circuit structure of a heater voltage stabilization circuit (a heater transformer is included). It is a block diagram which shows the circuit structure of the conventional microwave power supply device (iron transformer system). It is a block diagram which shows the circuit structure of the conventional microwave power supply device (inverter system). It is a curve graph which shows the output intensity of the microwave output at each process of thin film formation by plasma CVD. FIG. 6 is a characteristic relationship diagram showing the relationship between ON time of applied voltage, microwave output intensity, low output time, start-up time, and high output time, and barrier properties and adhesion. It is a characteristic relationship figure which shows ON time and barrier property relationship in a high output stage.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Microwave power supply device 11 AC power supply 12 Voltage value adjustment circuit 12-1 Voltage value setting part 13 Applied voltage control circuit 13-1 SCR phase control part 14 Transformer circuit 15 Rectifier circuit 16 Drive circuit 17 Microwave generation part 18 Feedback part 19 ON time adjustment circuit 19-11 output setting device 19-12 amplifier 19-13 toron circuit 19-14 diode bridge 19-15 transformer 19-16 capacitor 19-17 pulse transformer 20 smoothing circuit 21 inverter circuit section 21-1 half bridge inverter 22 double voltage rectification smoothing circuit 23 voltage value adjustment circuit 23-1 variable output input 24 ON time adjustment circuit 24-1 variable pulse width input 25 inverter drive circuit unit 25-1 variable control circuit 25-2 gate drive circuit 31 switching regulator 2 reference voltage setting unit 40 heater voltage stabilizing circuit

Claims (12)

A microwave power supply device that drives a microwave generator by applying a voltage,
A voltage value adjusting circuit for determining a peak output of the applied voltage;
An ON time adjusting circuit for determining an ON time of the applied voltage;
An applied voltage control circuit that forms a waveform of the applied voltage based on the peak output from the voltage value adjusting circuit and / or the ON time from the ON time adjusting circuit. Microwave power supply. The applied voltage control circuit is
An inverter circuit unit for forming the applied voltage into a high-frequency pulse waveform;
The inverter drive circuit unit that drives the inverter circuit unit based on the peak output from the voltage value adjustment circuit and / or the ON time from the ON time adjustment circuit. Item 2. The microwave power supply device according to Item 1. The inverter circuit unit has a switching element that forms the applied voltage at a high frequency,
The inverter drive circuit unit is
Based on the peak output from the voltage value adjustment circuit and / or the ON time from the ON time adjustment circuit, a setting variable that forms a control signal indicating the adjustment value of the peak output and / or the ON time. A control unit;
The microwave power supply device according to claim 2, further comprising: a switching element driving unit that drives the switching element of the inverter circuit unit based on the control signal. A microwave power supply device that drives a microwave generator by applying a voltage,
A voltage value adjusting circuit for determining a peak output of the applied voltage;
An ON time adjusting circuit for determining an ON time of the applied voltage based on the peak output of the applied voltage determined by the voltage value adjusting circuit;
A microwave power supply apparatus comprising: an applied voltage control circuit that forms a waveform of the applied voltage based on the ON time from the ON time adjusting circuit. The microwave power supply device according to claim 4, wherein the voltage value adjustment circuit includes a transformer and / or a slidac that adjusts a peak output of the applied voltage. The ON time adjusting circuit is
An ON time adjusting unit that adjusts an ON time of the applied voltage based on the peak output of the applied voltage determined by the voltage value adjusting circuit;
A trigger generation unit that determines a trigger generation timing based on the ON time from the ON time adjustment unit;
The microwave power supply device according to claim 4 or 5, wherein the applied voltage control circuit includes a phase control unit that performs phase control of the applied voltage based on the generation timing of the trigger. A feedback unit that receives the applied voltage applied to the microwave generation unit as a feedback voltage;
The ON time adjusting unit of the ON time adjusting circuit is
The microwave power supply device according to claim 6, wherein the ON time is adjusted based on the feedback voltage from the feedback unit. The ON time adjustment circuit has an output setting device for setting a voltage value of the applied voltage,
The microwave power supply device according to claim 6 or 7, wherein the ON time adjusting unit adjusts the ON time based on the voltage value from the output setting device. The trigger generator has a pulse transformer that generates the trigger,
The ON time adjustment unit
A diode bridge for determining the ON time based on the feedback voltage from the feedback unit and / or the voltage value from the output setting device;
The microwave power supply device according to claim 6, further comprising a capacitor that applies a voltage indicating a constant value to the trigger generation unit. The microwave power supply device according to any one of claims 6 to 9, wherein the phase control unit includes a triac that controls the phase of the applied voltage based on the trigger signal. The microwave power supply device according to any one of claims 1 to 10, further comprising a switching regulator that stabilizes an alternating voltage applied as a power supply voltage to a predetermined voltage. The microwave power supply device according to any one of claims 1 to 11, further comprising a heater voltage stabilization circuit that stabilizes a heater voltage of the microwave generation unit.

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