JP5727450B2 - Supply power regulator and semiconductor manufacturing apparatus - Google Patents

Description

  The present invention relates to a supply power regulator for supplying power to a heater and a semiconductor manufacturing apparatus using the same.

  FIG. 3 shows a conventional heater power supply regulator. The heater power supply regulator 20 has a power receiving terminal block 2 connected to the AC power source 1 at its input end and a distribution terminal block 6 connected to the heater 7 at its output end. A power breaker 3, a power transformer 4, and a power control thyristor 5 as a power regulator are connected between the power receiving terminal block 2 and the distribution terminal block 6. The heater 7 is provided with a temperature measuring thermocouple 8.

The AC power supply 1 is received by the power receiving terminal block 2, and the power is supplied to the power transformer 4 through the power breaker 3. The power transformed by the power transformer 4 is controlled by the power control thyristor 5 and supplied to the heater 7 from the distribution terminal block 6. Thereby, the heater 7 is heated and the temperature of the heater 7 changes. The heater temperature is measured by the temperature measuring thermocouple 8 and input to the temperature controller 9. The temperature controller 9 calculates the difference between the measured temperature measured by the thermocouple 8 for temperature measurement and the set temperature, and calculates the amount of power to be supplied to the heater 7 according to the temperature difference. The calculation result is converted into a phase control amount and output as a control signal from the temperature controller 9 to the power control thyristor 5. The power control thyristor 5 supplies power to the heater 7 according to the timing of the control signal.
In this way, the heater power supply regulator 20 determines the timing at which the temperature controller 9 outputs the control signal after detecting the heater temperature, and phase-controls the power control thyristor 5 in accordance with this timing. Thus, the temperature of the heater 7 is controlled to be the set temperature.

  This phase control method is shown in FIG. 4A shows a power supply waveform of the AC power supply, and FIG. 4B shows a power control thyristor control signal for controlling the power control thyristor. In the phase control method, for each cycle of the AC power supply, the period from the generation of the power control thyristor control signal to the zero volt time of the power supply waveform is defined as the power control period A, and the period from the zero volt time to the generation of the control signal Reactive power period B. Further, the power source is required to have a maximum power that is greater than that required when the temperature is stable. Therefore, the effective power when the temperature is stable is only about 60% to 80% of the maximum power, and the rest is reactive power, so that the efficiency as a power source is poor.

  In order to improve this, there have been devised methods that employ zero-crossing control in which reactive power does not occur in principle or increase the active power ratio to 85% or more by using a phase advance capacitor for power factor improvement.

  The zero cross control is the same as FIG. 3 in terms of circuit, but generally differs from the power control element in that an SSR (solid state relay) is used instead of a thyristor and the contents of the control signal are changed. FIG. 5 shows how this zero cross control is performed. FIG. 5A shows a power supply waveform of the AC power supply, and FIG. 5B shows a power control SSR control signal for controlling the SSR. Employs an ignition system that turns on the SSR when the power supply waveform is at zero volts, and the AC power supply has a specified time (A + B) of one cycle (one cycle time), during which the power control SSR control signal is output and energized The period is a power control period A, and the other period is a non-energization period B in which power is not consumed. Zero-crossing control simply turns the power on / off, and in principle, no reactive power is generated.

  FIG. 6 shows a control method using a phase advance capacitor. The solid line in FIG. 6A shows the supply-side AC power supply waveform W1, and the dotted line shows the control-side power supply waveform W2. FIG. 6B shows a power control thyristor control signal. When the supply-side AC power supply waveform W1 indicated by the solid line is controlled by this control signal, the reactive power period B is long, so that the power control at the phase angle P1 remains at 70%, for example. However, if the control-side power supply waveform W2 indicated by the dotted line whose phase is advanced by the phase advance capacitor is controlled by the power control thyristor control signal, the reactive power period B ′ is reduced by the advance of the phase angle P2, The apparent power factor improves and power control increases to 90%.

  However, in the case of zero-cross control, an SSR having a relatively large on-voltage is used as a power control element as compared with a high-speed switching power control semiconductor such as an insulated bipolar transistor IGBT (Insulated Gate Bipolar Transistor). For this reason, there is a problem that the responsiveness of the heater temperature is deteriorated. In the case of using a phase advance capacitor, power adjustment is required to limit the profile up to the maximum power due to the correction of the phase advance capacitor. This is because the phase is advanced, and suddenly the maximum power is lost. Therefore, it was not easy to use.

  As described above, in the power supply regulator using the SSR as the conventional power control element, there is a problem that the temperature responsiveness is deteriorated when the power control thyristor is temperature controlled by performing the zero cross control. In addition, in the case of using a phase advance capacitor, it is necessary to adjust the power to limit the profile up to the maximum power, which is inconvenient. Furthermore, as can be said in common with both, there is a problem that stability against power supply fluctuations and load fluctuations is poor because measures for power supply fluctuations and load fluctuations are not taken.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and is compact, excellent in temperature responsiveness, excellent in stability against power supply fluctuation and load fluctuation, and easy to use. Is to provide.

According to an aspect of the present invention, in a semiconductor manufacturing apparatus that carries out a heat treatment by carrying a substrate holder loaded with a plurality of substrates into a reaction furnace,
A heater provided around the reactor, and a supply power regulator that adjusts the supply power to the heater;
The power supply regulator converts an AC voltage of an AC power source into AC power corresponding to a frequency of a control signal and supplies the power to the heater, and a counter electromotive force generated by a switching operation of the IGBT converter. There is provided a semiconductor manufacturing apparatus comprising a regeneration IGBT converter that regenerates electric power and returns it to the AC power source.

  According to the embodiment of the present invention, it is possible to obtain a supply power regulator and a semiconductor manufacturing apparatus that are compact, excellent in temperature responsiveness, excellent in stability against power supply fluctuation and load fluctuation, and easy to use.

It is a block diagram of the power supply regulator by one embodiment of this invention. It is a specific block diagram of the principal part of the power supply regulator by one embodiment of this invention. It is a block diagram of the supply power regulator by a prior art example. It is explanatory drawing of how to give the electric power by the conventional phase control. It is explanatory drawing of how to give the electric power by the zero cross control common to the former and the Example. It is explanatory drawing of the power factor improvement by the conventional phase advance capacitor system. It is a principal part figure of the power supply regulator by one embodiment of this invention. It is a figure which shows the switching operation of the principal part of the supply power regulator by one Embodiment of this invention, and the voltage waveform at each point. FIG. 3 is a specific explanatory diagram of a power supply fluctuation detecting unit 22, a load fluctuation detecting unit 23, and a frequency variable circuit 15 according to an embodiment of the present invention. It is a perspective view which shows an example of the heat processing apparatus for heat-processing a semiconductor substrate which is one of the processes which manufacture the semiconductor by one embodiment of this invention. It is sectional drawing which shows an example of the reaction furnace by one embodiment of this invention.

As a result of research to achieve the above-mentioned object, the present inventor found that the IGBT is optimal for the above-mentioned object when considering power consumption, high-speed switching, etc., and further switching the AC voltage directly with the IGBT, The present invention has been invented based on the knowledge that it is not necessary to provide a rectifier circuit.
An embodiment of the power supply regulator of the present invention will be described below.

  The supply power regulator according to the embodiment supplies the output of a converter that performs a high-speed switching operation to a heater as power, and an IGBT that is an element for high-speed switching power control is used for the converter device. The AC power of the AC power supply is directly switched by the IGBT and pulse-modulated AC power is supplied to the heater so that the reactive power is almost zero and the power supply is effectively used.

  As shown in FIG. 1, a supply power regulator 21 that supplies power from the AC power source 1 to the heater 7 includes a power receiving terminal block 2 connected to the AC power source 1 at its input end, and is connected to the heater 7 at its output end. And a distribution terminal block 6. The AC power supply 1 is a single-phase commercial power supply having a frequency of 50/60 Hz and an AC of 200 V, for example. The heater 7 is a resistance heater made of molybdenum disilicide, for example.

  A power breaker 3 is connected to the power receiving terminal block 2, and a power transformer 4 is further connected as necessary. The AC power source 1 is received by the power receiving terminal block 2 and supplied to the power transformer 4 through the power breaker 3. The power transformer 4 may not be used depending on the specifications of the heater 7. Note that the supply power regulator 21 may prepare a plurality of IGBT converters 11 so that the heater 7 can be divided into a plurality of regions and power control can be performed individually.

  On the secondary side of the power transformer 4, the input filter circuit 10, the IGBT converter 11, the power fluctuation detection means 22, the load fluctuation detection means 23, the temperature fluctuation detection means 24, and a frequency variable means (hereinafter referred to as “frequency fluctuation means”). Frequency variable circuit) 15 and an output side filter circuit 30. The electric power transformed by the power transformer 4 is supplied to the IGBT converter 11 controlled by the frequency variable circuit 15 through the input side filter circuit 10 and connected to the distribution terminal block 6 through the output side filter circuit 30. It can be added to the heater 7.

  Next, the input side filter circuit 10, the output side filter circuit 30, and the IGBT converter 11 will be described with reference to the main part diagram of the supply power regulator shown in FIG.

The input-side filter circuit 10 is a low-pass filter using LC as a filter method, and has a configuration in which filter elements are arranged in the order of CLC. The coil L is divided into an input line and a common line and is inserted into L1-1 and L1-2. The capacitor C1-1 before the LC is for removing a high-frequency component on the power supply waveform and for reducing the loss, and is preferably a capacitor having a very small capacity. The cut-off frequency of the low-pass filter is 1/10 to 1/40 (500 Hz to 2 KHz) of the switching frequency (the number of times the IGBT is turned on / off per second and 20 kHz in this embodiment) from the viewpoint of the power supply waveform and noise. Is set to Therefore, it is possible to cut off high frequency components and reliably supply electric power of the target commercial frequency (50 or 60 Hz) to the heater 7.
The input side filter circuit 10 suppresses electromagnetic noise generated by switching the IGBT converter 11 at high speed and high frequency. Therefore, induction of electromagnetic noise in the input line of the IGBT converter 11 connected to the AC power supply 1 side can be suppressed, and noise disturbance can be prevented from occurring in the AC power supply.

Similar to the input side filter circuit 10, the output side filter circuit 30 is a low-pass filter using LC as a filter system, and is configured in the order of filter elements LCC. The coil L is inserted into the output line and the common line by being divided into L2-1 and L2-2. Note that the capacitor C2-2 after the LC is a capacitor for removing a high-frequency component on the power supply waveform as described in the input-side filter circuit 10. Further, the cutoff frequency of this low-pass filter is similarly 500 Hz to 2 kHz.
The output filter circuit 30 smoothes (smooths) the output obtained by switching by the IGBT converter 11 and effectively removes harmonic components contained in the output.

  The IGBT converter 11 includes a power IGBT converter 11a and a regenerative IGBT converter 11b. The IGBT converter 11 is preferably a double arm type in order to perform switching of positive voltage / current and negative voltage / current waveform separately. The power IGBT converter 11a is composed of a high-speed rectifier circuit FRD1 and a chopper section having an IGBT2. The chopper section has an upper arm to which a chopper section PWM signal is applied and a lower arm. The regeneration IGBT converter 11b includes an IGBT 3 and a high-speed rectifier circuit FRD2.

  The alternating current is directly switched at the basic carrier frequency of high speed and high frequency by the IGBT2. For example, the switch timing by the PWM method detects a zero cross point from the alternating current of the supply source, and adjusts the control signal (PWM signal) based on the zero cross point. Then, the alternating current of the supply source is switched at the combined carrier frequency to obtain a pulse modulated wave, and this is supplied to the heater 7 via the output side filter circuit 30. The control signal output from the frequency variable circuit 15 changes the duty ratio of the control signal applied to the gate (arm) of the IGBT according to fluctuations (temperature, power, load).

  8 shows the switching operation of the main part of the supply power regulator shown in FIG. 7 and the voltage waveforms at the respective points ((a) to (e), (f) to (i)) shown in FIG. It is shown. The operation of the IGBT converter 11 will be described in detail with reference to FIG. First, the voltage waveform A of the commercial frequency AC power supply is supplied to the terminal block TB1 as shown in (a). The input frequency of the PWM signal to the IGBT converter 11 applied via the arm is fixed at 20 KHz (50 μsec). The chopper PWM signals as shown in (b) and (c) are applied to the upper arm and the lower arm of the IGBT 2, respectively. The voltage waveform B of the output of the IGBT converter 11 is such that the commercial frequency AC power is energized only when the IGBT 2 is ON (when the PWM signal is applied), and the commercial frequency AC power is shut off when the IGBT 2 is OFF. The output waveform is as shown in (d). This output is smoothed by the output side filter circuit 30, and the voltage waveform C of the commercial frequency with less distortion is output from the output side filter circuit 30 through the distribution terminal block (TB2) as shown in (e). In this way, the voltage peak value of the supply voltage output to the final load is controlled by changing the time during which the IGBT 2 is ON. Therefore, only the peak value can be controlled in the range of 0 to 70% and output to the load without changing the frequency of the supply voltage by the PWM signal to the IGBT 2 used in the IGBT converter 11.

  If the pulse width of the chopper PWM signal applied to the upper arm and lower arm of the IGBT 2 is larger than the pulse widths shown in (b) and (c) as shown in (f) and (g), the IGBT The voltage waveform B of the output of the converter 11 has a waveform as shown in (h), and the voltage waveform C of the supply voltage output to the final load is higher than that in (e) described above as shown in (i). The peak value can be increased.

Since the alternating current is directly switched by the IGBT 2 incorporated in the IGBT converter 11, a diode full-wave rectifier circuit becomes unnecessary on the input side of the IGBT converter 11.
The IGBT 2 which is a switching element constituting the IGBT converter 11 is a bipolar power transistor combined with a voltage-driven gate and has low gate drive power consumption and is suitable for high-speed switching. Further, it is a high-frequency and large-capacity element, and the on-voltage is significantly smaller than that of the MOSFET (SSR). The IGBT 2 is controlled at a high frequency in order to reduce reactive power.

The temperature fluctuation detecting means 24 detects the temperature fluctuation of the heater 7 and outputs a feedback signal corresponding to the fluctuation to the frequency variable circuit 15. The temperature variation detecting means 24 includes a temperature measuring thermocouple 8 as a temperature sensor and a temperature controller 9 for adjusting the heater temperature.
The required number of thermocouples 8 for temperature measurement are provided in the vicinity of the heater 7, and the heater temperature is measured by thermoelectromotive force. The temperature controller 9 obtains a temperature difference (temperature fluctuation) between the measured temperature of the heater 7 measured by the temperature measuring thermocouple 8 and the set temperature. The amount of power to be supplied to the heater 7 is calculated according to this temperature difference, and the calculation result is output to the frequency variable circuit 15 as a feedback signal. Moreover, the temperature controller 9 outputs an alarm when temperature abnormality is detected.

  The power fluctuation detection means 22 detects a fluctuation in output power from the input side filter circuit 10 and outputs a feedforward signal corresponding to the fluctuation to the frequency variable circuit 15. This power fluctuation detection means 22 includes a current transformer 12 that measures the current flowing through the output of the input side filter circuit 10, a voltage measurement line 13 that measures the output line voltage of the input side filter circuit 10, and a power supply voltage / current feed. And a forward circuit 14. In order to detect fluctuations in the output power, the power supply voltage / current feedforward circuit 14 calculates the difference between the measured current measured by the current transformer 12 and the set current and the measured voltage measured by the voltage measurement line 13 and the set voltage. Find the difference. The product (electric power) of these differences is the power supply fluctuation. This power fluctuation is applied to the frequency variable circuit 15 as a feedforward signal.

The load fluctuation detecting means 23 detects a fluctuation in the output power supplied to the heater 7 and outputs a feedback signal corresponding to the fluctuation to the frequency variable circuit 15. The load fluctuation detecting means 23 includes a voltage measuring line 17 for measuring the output line voltage of the output side filter circuit 30, a current transformer 18 for measuring a current flowing through the heater 7, and a control voltage / current feedback circuit 16. . In order to detect the load fluctuation, the control voltage / current feedback circuit 16 obtains the difference between the measurement voltage measured by the voltage measurement line 17 and the set voltage and the difference between the measurement current measured by the current transformer 18 and the set current. . The product (electric power) of these differences becomes the load fluctuation. This load variation is applied to the frequency variable circuit 15 as a feedback signal.
The current transformer 18 is preferably provided on the heater 7 side outside the distribution terminal block 6 in order to accurately measure the variation of the load current.

The frequency variable circuit 15 controls the frequency of the IGBT converter 11 according to the fluctuation results of the power fluctuation detection means 22 and the load fluctuation detection means 23. Specifically, the frequency variable circuit 15 includes a fluctuation signal output from the power supply voltage / current feedforward circuit 14 of the power fluctuation detection means 22 and the control voltage / current feedback circuit 16 of the load fluctuation detection means 23, and a temperature fluctuation. A gate control signal having a frequency corresponding to the amount of power to be supplied to the heater 7 is added to the gate of each IGBT constituting the IGBT converter 11 from the signal output from the temperature controller 9 of the detection means 24.
The frequency of the IGBT is controlled, and the electric power supplied to the heater 7 is controlled by changing the frequency substantially continuously. The controllability of power is improved as the frequency variable width is larger.
The frequency control by the frequency variable circuit 15 is the same as the VF (variable frequency) control of the VVVF control in that the frequency is changed. This frequency control includes PWM control for controlling the duty ratio while keeping the basic carrier frequency constant. In both the VF control and the PWM control, the IGBT is turned on at zero volts, so that the zero cross control is performed.

  In the power supply regulator 21 according to the above-described embodiment, the temperature controller 9 and the frequency variable circuit 15 control the temperature of the heater 7 to be the set temperature as follows.

  The temperature controller 9 calculates the temperature difference between the measured temperature and the set temperature, calculates the amount of power to be supplied to the heater 7 according to this temperature difference, and outputs the calculation result to the frequency variable circuit 15. The frequency variable circuit 15 adds a gate control signal having a frequency corresponding to the output value from the temperature controller 9 to the IGBT converter 11. The IGBT converter 11 converts the AC power from the input side filter circuit 10 into AC power having a frequency corresponding to the gate control signal of the frequency variable circuit 15 and supplies the AC power to the heater 7 via the output side filter circuit 30. By supplying electric power to the heater 7, the temperature of the heater 7 changes.

  Feedback control is performed by such a closed loop of temperature fluctuation detection → control calculation → output of output value → temperature change → temperature fluctuation detection →. Since the output amount is determined by the temperature controller 9 and the frequency variable circuit 15 after detecting the temperature state, the feedback control can be performed satisfactorily. Therefore, the temperature fluctuation of the heater is corrected, stable electric power is supplied to the heater 7, and the heater 7 can be maintained at a predetermined temperature. Further, since the frequency control is zero-cross control, there is no reactive power and high-efficiency control can be performed.

  As described above, when the heater temperature is favorably feedback controlled, if the voltage of the AC power supply 1 fluctuates, the voltage fluctuation appears in the output of the input side filter circuit 10 as current fluctuation and voltage fluctuation. The current fluctuation and voltage fluctuation are measured by the current transformer 12 and the voltage measurement line 13 and detected by the power supply voltage / current feedforward circuit 14. A control signal corresponding to the power fluctuation is input to the frequency variable circuit 15 from the power supply voltage / current feedforward circuit 14. Using this signal, the frequency variable circuit 15 outputs a gate control signal having a frequency corresponding to the difference between the power supply power and the set power. The gate control signal is added to the IGBT converter 11 to control the frequency of the IGBT converter 11. Therefore, voltage fluctuation of the AC power supply 1 is corrected, and stable power can be supplied to the heater 7. Further, since the frequency control is zero-cross control, there is no reactive power and high-efficiency control can be performed. By this feedforward control, the response characteristics from the input side filter (AC power supply) 10 to the thermocouple 8 for temperature measurement are improved.

In addition, when the heater temperature is favorably feedback-controlled as described above, if the heater 7 is disturbed (for example, exposed to outside air) or the load changes due to a slight change in the properties of the heater, Appears as fluctuations in the output power of the IGBT converter 11. That is, the load current flowing through the heater 7 and the load voltage applied to the heater 7 vary. The current fluctuation and voltage fluctuation are detected by the current transformer 18 and the voltage measurement line 17 and measured by the control voltage / current feedback circuit 16. A signal corresponding to the power fluctuation is input from the control voltage / current feedback circuit 16 to the frequency variable circuit 15. Using this signal, the frequency variable circuit 15 outputs a gate control signal having a frequency corresponding to the difference between the power supply power and the set power. The gate control signal is added to the IGBT converter 11 to control the frequency. Therefore, the load fluctuation is corrected and stable power can be supplied to the heater 7. Further, since the frequency control is zero-cross control, there is no reactive power and high-efficiency control can be performed.
This load fluctuation control has two steps, disturbance → power fluctuation detection, compared to temperature fluctuation control through three steps of disturbance → heater temperature change → thermocouple detection, and the thermocouple detection step can be omitted. Is fast.
In the above embodiment, the power supply fluctuation detection means 22, the load fluctuation detection means 23, the temperature fluctuation detection means 24, and the frequency variable circuit 15 are provided in the supply power regulator 21, but the load (heater) is not limited to this form. The power fluctuation detection means 22, the load fluctuation detection means 23, the temperature fluctuation detection means 24, and the frequency variable circuit 15 are provided as a combination of a known power regulator for adjusting the power supplied to the power supply) and a means for outputting the control signal. May be.

  Another embodiment of the process in which the frequency variable circuit 15 outputs the gate control signal to the IGBT from the fluctuation signals from the power fluctuation detection means 22, the load fluctuation detection means 23, and the temperature fluctuation detection means 24 is described with reference to FIG. Will be described.

  The power fluctuation detection means 22 converts the current by the current transformer 12 and the voltage by the voltage measurement line 13 from the effective value (RMS) to DC by the AC / DC converters 22a and 22b, respectively, and by the calculator 22c, current (DC) × voltage. (DC) = Primary power is calculated and input to the frequency variable circuit 15 as the primary power fluctuation feedback signal FB1.

  The load fluctuation detecting means 23 converts the current by the current transformer 18 and the voltage by the voltage measurement line 17 from the effective value (RMS) into DC by the AC / DC converters 23a and 23b, respectively, and the arithmetic unit 23c converts current (DC) × voltage. (DC) = Secondary power is calculated and input to the frequency variable circuit 15 as the secondary load fluctuation feedback signal FB2.

  The temperature fluctuation detecting means 24 inputs the signal output from the temperature controller 9 to the frequency variable circuit 15 as a power setting signal.

  The frequency variable circuit 15 has two power gain adjusters 15a and 15b and one power setting gain adjuster 15c inside, and each signal level can be adjusted individually by analog calculation or CPU calculation. Adjust the level. Then, each level-adjusted signal is input to the adder 15f to perform addition. This addition is also performed by analog calculation or CPU calculation.

In the above configuration, when the primary side power fluctuation feedback signal FB1 and the secondary load fluctuation feedback signal FB2 are input to the frequency variable circuit 15, respectively, the primary side feedback power fluctuation signal FB1 and the secondary load fluctuation feedback signal. The gain of FB2 is adjusted by the power gain adjusters 15a and 15b, inverted by inverters 15d and 15e, respectively, and input to the adder 15f. The adder 15f compares the feedback signal FB1 ′ (FB2 ′) and the feedback signal FB1 (FB2) when outputting the power setting signal in advance. The difference is added to the power setting signal as power supply fluctuation (load fluctuation).
When the power setting signal is input from the temperature variation detecting unit 24 to the frequency variable circuit 15, the gain of the power setting signal is adjusted by the power setting gain adjuster 15c and input to the adder 15f. When the power supply fluctuation or the load fluctuation occurs, the frequency variable circuit 15 uses the fluctuation of the primary side power fluctuation feedback signal FB1 and the secondary side load fluctuation feedback signal FB2 adjusted in gain as described above as power in the adder 15f. In addition to the setting signal, an optimum power setting signal is output as a gate control signal (IGBT frequency setting signal).

  As described above, a high-frequency and large-capacity IGBT is used as an element constituting a semiconductor converter for high-speed switching power control, and feed-forward control for power supply fluctuation and feedback control for load fluctuation are incorporated in feedback control for temperature control. Therefore, the temperature stability and the stability against power supply fluctuation and load fluctuation are extremely excellent, and high stability in heater temperature can be obtained. In particular, it is possible to capture power supply voltage fluctuations and load fluctuations in addition to temperature fluctuations only by adopting an IGBT which is a high-frequency and large-capacity element.

  FIG. 2 is a specific explanatory diagram of the input-side filter circuit 10, the IGBT converter 11, and the output-side filter circuit 30 described above.

  Both the input side filter circuit 10 and the output side filter circuit 30 are configured by normal mode filter circuits. That is, the input side filter circuit 10 includes a choke coil ACL1 connected in series to the input line 31, and a plurality of parallel connections between the input line 31 and the common line 33 on the power IGBT converter 11a side of the choke coil ACL1. Consists of capacitors CF1 to CF6. When the input side filter circuit 10 is configured by a normal mode filter circuit, electromagnetic noise leaking from the IGBT converter 11 to the input side can be effectively attenuated.

  The output side filter circuit 30 includes a choke coil ACL2 connected in series to the output line 32, and a plurality of capacitors CF7 to CF12 connected in parallel between the output line 32 and the common line 33 on the heater 7 side of the choke coil ACL2. It consists of. If the output side filter circuit 30 is configured by a normal mode filter circuit, harmonic components contained in the AC power output from the IGBT converter 11 can be effectively removed. Further, in the normal mode filter in which no element is provided in the common line 33, a high frequency spike component (back electromotive force) can be effectively returned from the common line 33 to the regenerative IGBT converter 11b via the heater 7. . As a result, it is possible to effectively perform power regeneration without releasing energy in the common line 33, and the energy efficiency of the AC power source 1 can be improved.

  The IGBT converter 11 includes a power IGBT converter 11a that is a main circuit switching element unit that performs ON / OFF of the main circuit, and a regeneration IGBT converter 11b that operates when the main circuit switching element is OFF. Integrated and packaged. Each element is composed of two systems, a positive voltage / current and a negative voltage / current, and a high-speed rectifying element is also arranged to prevent backflow.

The power IGBT converter 11a includes a high-speed rectifier circuit FRD1, a two-stage upstream switch circuit IGBT1 in series, a snubber circuit CRF1, and a two-stage upstream switch circuit (chopper part) IGBT2 in series. In FIG. 2, two IGBTs are prepared in order to flow a large amount of current. As a switching method, the power IGBT converter 11a performs ON / OFF control by PWM control (pulse width modulation) as described above. The regenerative IGBT converter 11b operates by determining whether the power supply voltage is positive or negative. Depending on a pure resistance load or a pure resistance load having an inductive load, it is desirable to have a circuit configuration that can adjust the switching operation with a delay time.
The high-speed rectifier circuit FRD1 is configured by a center tap type high-speed rectifier element in which the input line 31 is connected to the center tap, and rectifies the alternating current supplied from the input line 31 into a positive half wave and a negative half wave. Then, the upper switch circuit IGBT1 is divided into an upper stage and a lower stage according to the polarity.

Each of the front-stage switch circuit IGBT1 and the rear-stage switch circuit IGBT2 is configured by a tabular arm type IGBT stacked in series in two stages, and a free wheel diode is connected in parallel to each IGBT. The front-stage switch circuit IGBT1 and the rear-stage switch circuit IGBT2 are operated in parallel and directly switch the positive half-wave distributed by the high-speed rectifier circuit FRD1 with the upper-stage IGBT and the negative half-wave with the lower-stage IGBT.
The snubber circuit CRF1 is similarly configured as a tabular arm type, and is commonly connected to the front-stage switch circuit IGBT1 and the rear-stage switch circuit IGBT2, and generates a current flowing through the freewheel diode FWD in the circuit when each of the IGBTs constituting them is turned off. Consume as heat.

  The power IGBT converter 11a distributes the alternating current applied to the input line 31 by the high-speed rectifier circuit FRD1 according to the polarity, and switches the front stage switch circuit IGBT1 and the rear stage switch circuit IGBT2 to obtain the alternating current power. This is applied to the output side filter circuit 30. Further, the counter electromotive force generated in the power IGBT converter 11a is consumed by the snubber circuit CRF1.

The regenerative IGBT converter 11b includes a center tap type high-speed rectifier circuit FRD2 having a common line 33 connected to the center tap, a series of two upper and lower tabular switch circuits IGBT3, and a switch circuit IGBT3 in parallel. It is composed of two single type snubber circuits CRF2 and CRF3 to be connected.
In the regenerative IGBT converter 11b, the back electromotive force generated outside the IGBT converter 11 and returned from the common line 33 is distributed by the high-speed rectifier circuit FRD2 according to the polarity, and according to the polarity at each stage of the switch circuit IGBT3. Then, AC is directly switched to obtain regenerative power, and this regenerative power is returned to the AC power supply 1 via the power IGBT converter 11a and the input side filter circuit 10. In the snubber circuits CRF2 and CRF3, the back electromotive force generated in the regeneration IGBT converter 11b is consumed by heat.
The IGBT can be continuously changed from a frequency of zero to a frequency higher than the power supply frequency (for example, 300 Hz). However, when the frequency is higher than 300 Hz, the influence of the counter electromotive force generated due to the inductance element of the load. Cannot be ignored. However, in the present embodiment, since the regenerative IGBT converter 11b is provided, the back electromotive force of the inductive load can be efficiently returned to the AC power source 1, and therefore the influence can be ignored.

  FIG. 10 shows an example of a perspective view of a heat treatment apparatus 110 as a semiconductor manufacturing apparatus for performing heat treatment on a semiconductor substrate, which is one of processes for manufacturing a semiconductor according to an embodiment of the present invention. This heat treatment apparatus 110 is a batch type vertical heat treatment, and has a casing 112 in which a main part is arranged.

  A reaction furnace 140 is disposed on the upper side of the back side in the housing 112. The substrate support 130 loaded with a plurality of substrates is carried into the reaction furnace 140 and subjected to heat treatment.

  FIG. 11 shows an example of a cross-sectional view of the reaction furnace 140. The reaction furnace 140 has a reaction tube 142 made of quartz. The reaction tube 142 has a cylindrical shape with its upper end closed and its lower end open. A quartz adapter 144 is disposed below the reaction tube 142 so as to support the reaction tube 142. A reaction vessel 143 is formed by the reaction tube 142 and the adapter 144. A heater 146 is disposed around the reaction tube 142 excluding the adapter 144 in the reaction vessel 143.

  A lower portion of the reaction vessel 143 formed by the reaction tube 142 and the adapter 144 is opened to insert the substrate support 130, and the open portion (furnace port portion) of the furnace port seal cap 148 has a lower end flange of the adapter 144. It is made to seal by contact | abutting to the lower surface of this. The furnace port seal cap 148 supports the substrate support 130 and is provided so as to be movable up and down together with the substrate support 130. The substrate support 130 supports a large number of substrates, for example, 25 to 100 substrates 154 in a substantially horizontal state with multiple gaps and is loaded into the reaction tube 142.

  The adapter 144 is provided with a gas supply port 156 and a gas exhaust port 159 integrally with the adapter 144. A gas introduction pipe 160 is connected to the gas supply port 156, and an exhaust pipe 162 is connected to the gas exhaust port 159.

  The processing gas introduced from the gas introduction pipe 160 to the gas supply port 156 is supplied into the reaction tube 142 via the gas introduction path 164 provided in the side wall portion of the adapter 144 and the nozzle 166.

Next, the operation of the heat treatment apparatus 110 configured as described above will be described.
In the following description, the operation of each unit constituting the heat treatment apparatus 110, that is, the substrate processing apparatus for performing the heat treatment, is controlled by the controller 170.

  First, when a pod 116 containing a plurality of substrates 154 is set on the pod stage 114, the pod 116 is transferred from the pod stage 114 to the pod shelf 120 by the pod transfer device 118 and stocked on the pod shelf 120. Next, the pod conveying device 118 conveys and sets the pod 116 stocked on the pod shelf 120 to the pod opener 122, opens the lid of the pod 116 by the pod opener 122, and the pod 116 by the substrate number detector 124. The number of substrates 154 accommodated in is detected.

  Next, the substrate 154 is taken out from the pod 116 at the position of the pod opener 122 by the tweezer 132 of the substrate transfer machine 126 and transferred to the notch aligner 128. The notch aligner 128 detects and aligns notches while rotating the substrate 154. Next, the substrate 154 is taken out from the notch aligner 128 by the tweezer 132 of the substrate transfer machine 126 and transferred to the substrate support 130.

  In this way, when one batch of substrates 154 is transferred to the substrate support 130, for example, a substrate in which a plurality of substrates 154 are loaded in the reaction furnace 140 (reaction vessel 143) set to a temperature of about 600 ° C. The support 130 is inserted, and the reactor 140 is sealed with a furnace port seal cap 148. Next, the furnace temperature is raised to the heat treatment temperature, and processing is performed in the reaction tube 142 from the gas introduction pipe 160 through the gas supply port 156, the gas introduction path 164 provided in the side wall of the adapter 144, and the nozzle 166. Introduce gas. When heat-treating the substrate 154, the substrate 154 is heated to a set temperature of 1000 ° C., for example. When adjusting the power supplied to the heater to reach the set temperature, the power supply regulator of the embodiment is used as a part of the controller 170.

  When the heat treatment of the substrate 154 is completed, for example, after the temperature in the furnace is lowered to about 600 ° C., the substrate support 130 supporting the substrate 154 after the heat treatment is unloaded from the reaction furnace 140 and supported by the substrate support 130. While all the substrates 154 are cooled, the substrate support 130 is put on standby at a predetermined position. Next, when the substrate 154 of the substrate support 130 that has been waiting is cooled to a predetermined temperature, the substrate transfer device 126 takes out the substrate 154 from the substrate support 130, and the empty pod set in the pod opener 122. It conveys to 116 and accommodates. Next, the pod carrying device 118 carries the pod 116 containing the substrate 154 to the pod shelf 120 or the pod stage 114 to complete a series of processes.

  As described above, the supply power regulator according to the embodiment has the following effects.

Since the AC voltage of the AC power supply is directly switched by the IGBT converter, a diode full-wave rectifier circuit in front of the IGBT converter becomes unnecessary, and a compact supply power regulator can be realized.
For example, the full-wave rectifier circuit has a size of about 200 (W) × 350 (D) × 100 (H) in the 200A class, although it depends on its capacity. The overall size of the power supply regulator provided with such a full-wave rectifier circuit is about 600 (W) × 800 (D) × 1200 (H). In the present embodiment, since there is no full-wave rectifier circuit, the size of the entire power supply regulator can be reduced to about 80%.

  Moreover, since the electromagnetic noise generated by the IGBT converter is suppressed by the input side filter circuit, it is possible to prevent the electromagnetic noise from being mixed into the AC power supply. Therefore, it is possible to prevent noise disturbance from occurring in the AC power supply. Further, induction of electromagnetic noise in the input cable from the AC power source to the IGBT converter can be suppressed.

  Moreover, since the harmonic component contained in the output of the IGBT converter is suppressed by the output side filter circuit, the harmonic component in the AC power supplied to the heater can be attenuated.

  Moreover, since the IGBT converter for regeneration is provided and the back electromotive force generated outside the IGBT converter is regenerated and returned to the AC power supply, the energy efficiency of the AC power supply can be improved. In particular, since the IGBT converter is switched at a high speed and a high frequency, the number of occurrences of the counter electromotive force is so large and the power regeneration is frequently performed, which can greatly contribute to the improvement of energy efficiency.

Since the power supply voltage fluctuation is taken as feedforward control and the load fluctuation is taken as feedback control, it is incorporated into the temperature fluctuation feedback control, so that a control system having excellent temperature stability can be provided. In addition, stable power control is possible, and usability is good.
Since zero-crossing control is used, it is possible to provide a highly efficient supply power regulator that can effectively use power source power that has no reactive power in principle.

  Since the existing temperature controller 9 is used to add the output to the frequency variable circuit 15 and output the gate control signal of the IGBT, it can be compatible with the conventional system, and a little The system can be easily changed from the conventional system to this system simply by making a change. In addition, the existing temperature controller is not used, and the calculation function is transplanted to the frequency variable circuit 15 as in the case of power supply fluctuation or load fluctuation, so that the temperature controller is simply a circuit that detects only the temperature fluctuation. You may make it comprise.

  By adopting a high-speed switching element, power can be saved and necessary power can be obtained without waste. In particular, since an IGBT, which is a high-frequency element, is used, it is excellent in temperature responsiveness and suitable for heater control in the vicinity of an instrumentation line that dislikes noise.

  In the above-described embodiment, both the power supply voltage fluctuation and the load fluctuation are taken into the control in addition to the temperature fluctuation, but only the power supply voltage fluctuation is taken into the control in the temperature fluctuation control, or the temperature fluctuation Only load fluctuations may be taken into the control. In the former, stable supply power can be obtained by correcting the voltage fluctuation of the supply power supply. In the latter, it is possible to suppress the load fluctuation of the heater.

  From the embodiment of the present invention, it becomes possible to reduce the surge current and high-frequency noise generated at the time of high-speed switching, which has caused malfunctions and damage to the equipment used, and malfunctions to the peripheral equipment, and distortion can be reduced. It is now possible to produce a small, clean AC sine wave output.

  Further, the supply power regulator 21 of the above-described embodiment can be used for a semiconductor manufacturing apparatus including a reaction furnace heated by a heater. The reaction furnace includes a quartz tube and a cylindrical heater that heats the quartz tube from the outside. In order to heat this heater, the supply power regulator of the embodiment is used. If the supply power regulator described above is used in a semiconductor manufacturing apparatus, the heater temperature can be stable, and a high-performance semiconductor device can be obtained.

Hereinafter, preferred embodiments of the present invention will be additionally described.
The first aspect is provided on the input side of the IGBT converter, which converts the AC voltage of the AC power source into AC power corresponding to the frequency of the control signal and supplies the AC power to the heater. An input side filter circuit that suppresses electromagnetic noise generated in the IGBT converter, and an output that is provided on the output side of the IGBT converter and suppresses harmonic components contained in AC power output from the IGBT converter A side filter circuit, temperature fluctuation detection means for detecting temperature fluctuations of the heater, power supply fluctuation detection means for detecting power fluctuation of the AC power supply from an AC voltage supplied from the AC power supply to the IGBT converter, A load fluctuation detecting means for detecting a load fluctuation from AC power supplied from the IGBT converter to the heater, the temperature fluctuation detecting means, the power supply fluctuation detecting means, and Frequency variable means for calculating the amount of power to be supplied to the heater according to each detection result of the load fluctuation detection means, and controlling the frequency of the control signal applied to the IGBT converter according to the calculation result; And a supply power regulator characterized by comprising:

  According to this aspect, since the AC voltage of the AC power source is directly switched by the IGBT converter, the rectifier circuit in the previous stage of the IGBT converter is not required, and a compact power source can be realized.

Moreover, since the electromagnetic noise generated by the IGBT converter is suppressed by the input side filter circuit, it is possible to prevent the electromagnetic noise from being mixed into the AC power supply.
Moreover, since the harmonic component contained in the output of the IGBT converter is suppressed by the output side filter circuit, it can be prevented that the harmonic component is contained in the AC power supplied to the heater.

  Further, the temperature fluctuation is detected by the temperature fluctuation detecting means, the electric energy corresponding to the detection result is calculated by the frequency variable means, and the frequency of the IGBT converter is controlled according to the calculation result. The power supply is feedback controlled. Therefore, the temperature of the heater can be kept good at a predetermined temperature.

  Further, when the AC power supply fluctuates, the fluctuation appears as a fluctuation in power on the input side of the IGBT converter. The power fluctuation detection means detects this power fluctuation, the frequency variable means calculates the amount of power according to the detection result, and frequency-controls the IGBT converter according to the calculation result, thereby supplying power to the power fluctuation. Feedforward control. Accordingly, it is possible to suppress the disturbance of the heater temperature that occurs when the power supply fluctuates when the feedback control is favorably performed and the amount of power supplied to the heater fluctuates.

  Further, when the load fluctuates, the fluctuation appears as a fluctuation of the electric power supplied to the heater. The load fluctuation detecting means detects this power fluctuation, the frequency variable means calculates the amount of power corresponding to the detection result, and frequency-controls the IGBT converter according to the calculation result, thereby reducing the supply power for the load fluctuation. Feedback control. Therefore, it is possible to suppress the disturbance of the heater temperature that occurs when the load fluctuation occurs when the feedback control is well performed and the control of the amount of power supplied to the heater is greatly disturbed by the load fluctuation.

  As described above, since the feed-back control with respect to the power supply fluctuation and the feedback control with respect to the load fluctuation are incorporated into the feedback control with respect to the temperature control using the IGBT converter, the temperature stability and the stability with respect to the power supply fluctuation and the load fluctuation are increased. Extremely excellent and high stability in heater temperature is obtained. Moreover, since the IGBT converter is caused to perform a high-speed switching operation, the temperature response is excellent. In addition, since the control does not depend on the correction of the phase advance capacitor, the usability is improved. Furthermore, since the converter is composed of an IGBT, the transient response is particularly excellent. Moreover, since the frequency control of IGBT is zero cross control, the efficiency of a power supply can be improved.

According to a second aspect, in the first aspect, the IGBT converter includes a regenerative IGBT converter that regenerates a back electromotive force generated by a switching operation of the IGBT converter and returns the back electromotive force to the AC power source. It is the supply power regulator characterized.
Since the IGBT converter includes an IGBT converter for regeneration and regenerates the back electromotive force released as thermal energy and returns it to the AC power supply, the energy efficiency of the AC power supply can be increased.

  A third aspect is a semiconductor manufacturing apparatus using the supply power regulator of the first or second aspect as a heater power source. Since the power supply regulator according to the first or second aspect of the present invention that provides high stability in the heater temperature is provided, a high-performance semiconductor device can be manufactured.

DESCRIPTION OF SYMBOLS 1 AC power supply 7 Heater 8 Thermocouple 9 for temperature measurement Temperature controller 10 Input side filter circuit 11 IGBT converter 20 Output side filter circuit 21 Supply power regulator 14 Power supply voltage / current feedforward circuit 16 Control voltage / current feedback circuit 15 Frequency variable circuit (frequency variable means)
22 Power fluctuation detection means 23 Load fluctuation detection means 24 Temperature fluctuation detection means

Claims (8)

A power supply regulator that converts AC voltage of an AC power source into AC power corresponding to the frequency of the control signal and adjusts the power supplied to the load, and is stacked in two upper and lower stages in series, and the upper IGBT converter Two power IGBT converters composed of lower IGBT converters connected in parallel to the front and rear stages respectively, and rectifying the AC voltage into a positive half wave and a negative half wave, and depending on the polarity, An upper power IGBT converter and a power rectifier circuit that distributes to the lower power IGBT converter;
Temperature fluctuation detecting means for detecting a temperature fluctuation corresponding to a temperature difference between the measured temperature of the load and a set temperature as a power setting signal;
Power fluctuation detection means for detecting a power fluctuation of the AC power as a power fluctuation feedforward signal from an AC voltage supplied from the AC power to the power IGBT converter;
Load fluctuation detecting means for detecting a load fluctuation as a load fluctuation feedback signal from AC power supplied from the power IGBT converter to the load;
According to the detection results of the temperature fluctuation detection means, the power fluctuation detection means, and the load fluctuation detection means, feed-forward control for the power fluctuation and feedback control for the load fluctuation are incorporated in the feedback control for the temperature fluctuation. The power fluctuation feedforward signal and the fluctuation of the load fluctuation feedback signal are added to the power setting signal, and the adjusted optimum power setting signal is output to the power IGBT converter as a gate control signal. Frequency variable means for controlling the frequency of the control signal;
Supply power regulator with. Furthermore, it has a snubber circuit,
The power supply regulator according to claim 1, wherein the snubber circuit consumes back electromotive force generated as heat when the upper IGBT converter and the lower two IGBT converters of the plurality of power IGBT converters are turned off as heat. . Furthermore, an IGBT converter for regeneration is configured,
The regenerative IGBT converter switches back electromotive force generated and returned on the load side to obtain regenerative power, and returns the regenerative power to the AC power supply via the power IGBT converter. The power supply regulator according to 1. The regenerative IGBT converter includes an upper IGBT converter and a lower IGBT converter stacked in two stages in series,
Further, the back electromotive force is rectified into a positive half wave and a negative half wave, and distributed to the upper IGBT converter and the lower IGBT converter of the regenerative IGBT converter according to polarity. With rectifier circuit,
The IGBT converter in the upper stage of the regenerative IGBT converter obtains regenerative power by switching the positive half wave during the positive half wave period of the back electromotive force, and the regenerative power is supplied to the power IGBT converter. Through the AC power supply, the negative half-wave period is set to the off state,
The IGBT converter in the lower stage of the regenerative IGBT converter is set to an off state during the positive half-wave period of the back electromotive force, and the negative half-wave is switched to regenerate during the negative half-wave period. The supply power regulator according to claim 3, wherein power is obtained and the regenerative power is returned to the AC power supply via the power IGBT converter.   2. The supply power regulator according to claim 1, further comprising: a free wheel diode connected in parallel to each of the plurality of upper-stage IGBT converters and the plurality of lower-stage IGBT converters of the power IGBT converter.   The power IGBT converter further includes a snubber circuit that consumes the current flowing through the free wheel diode as heat that is generated when the plurality of upper-stage IGBT converters or the plurality of lower-stage IGBT converters are turned off. Item 6. The power supply regulator according to Item 5. The two upper IGBT converters switch the positive half-wave based on the control signal during the positive half-wave period of the AC voltage, and are set to the off state during the negative half-wave period. the two IGBT converter positive period of the half-wave of the AC power source is set to oFF state, claims 1 to 6 periods of negative half wave switching the negative half-wave based on the control signal Supply power regulator in any one of .   A semiconductor manufacturing apparatus comprising the supply power regulator according to claim 1.

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