JP2006085907A - Power supply device and semiconductor manufacturing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To predict the disconnection of a heater at an early stage and to prevent a substrate from being locked out. <P>SOLUTION: A power supply device 21 is configured to have a power feedback unit 23 and a temperature control unit 24 and to supply power from an AC power supply 1 to a heater 7. At controlling heater supply power, the control unit 24 sends a temperature control signal to the feedback unit 23 via a line 100 and the feedback unit 23 superimposes a power control signal on the temperature control signal to control a thyristor circuit for power adjustment 5. At determining heater deterioration, the feedback unit 23 feeds a measured current and applies a measured voltage to the control unit 24, and the control unit 24 determines the deterioration in the heater 7 on the basis of obtained heater resistance based on the measured current and the measured voltage and also on the basis of resistance at a reference time of the heater 7 obtained based on the measured temperature and a resistance temperature coefficient. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a power supply device that supplies power to a heater, and a semiconductor manufacturing apparatus equipped with the power supply device.

  FIG. 5 shows the configuration of a conventional heater power supply device. The heater power supply device 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 adjustment thyristor circuit 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 supplied to the power transformer 4 through the power breaker 3. The power transformed by the power transformer 4 is controlled by the power adjustment thyristor circuit 5 and supplied from the distribution terminal block 6 to the heater 7. Thereby, the heater 7 is heated and the temperature of the heater 7 changes. The heater temperature is measured by the 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 and the set temperature, and calculates the amount of power to be supplied to the heater 7 according to the temperature difference. This calculation result is converted into a phase control amount and output as a control signal from the temperature controller 9 to the power adjustment thyristor circuit 5. The power adjusting thyristor circuit 5 supplies power to the heater 7 according to the timing of the control signal.

However, in the conventional technique, as a method for detecting the disconnection of the heater, there is no choice but to monitor the current of the heater. In order to replace the heater before the disconnection, the judgment can be made based on the material of the heater and the environment in use. There wasn't.
When the heater is disconnected, there is a problem in that productivity is affected such that normal heat treatment cannot be performed in the heating furnace and a lot defect of the substrate is caused. In particular, in a vertical furnace of a semiconductor manufacturing apparatus, the influence is large because the number of objects to be processed at a time is large. In order to compensate for this, a spare heater is prepared and periodically replaced. However, since the life of the heater is unsatisfactory, there is also a problem that it is disconnected within the life prediction range.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a power supply device that can solve the above-described problems of the prior art, predict a heater disconnection at an early stage, and prevent substrate lotout, and a semiconductor manufacturing apparatus equipped with the power supply device There is to do.

1st invention is a power supply device which determines deterioration of a heater, supplying electric power from an alternating current power supply to a heater, The electric power regulator which supplies the electric power according to a control signal from the said alternating current power supply, The said heater A power feedback signal for controlling the power regulator and a temperature of the heater are measured by measuring a current and a voltage supplied to the power regulator, supplying a power control signal corresponding to the measured current and the measured voltage to the power regulator. A temperature control unit capable of controlling the power regulator by supplying a temperature control signal corresponding to the measured temperature to the power regulator, and connecting the power feedback unit and the temperature controller via a line. During the heater supply power control, a temperature control signal is sent from the temperature control unit to the power feedback unit, and the power feedback unit supplements the temperature control signal with the power control signal. The power regulator is controlled by the corrected control signal, and at the time of heater deterioration determination, the power feedback unit sends the measurement current and the measurement voltage to the temperature control unit, and the temperature control unit Deterioration of the heater is determined based on the heater resistance obtained on the basis of the measured voltage and the resistance at the reference time of the heater obtained on the basis of the measured temperature and the resistance temperature coefficient. It is a power supply device characterized by this.
According to the present invention, since it is possible to determine the degree of deterioration of the heater, it is possible to predict the disconnection of the heater at an early stage.

According to a second invention, in the first invention, the temperature control unit is based on a memory for storing a temperature coefficient of resistance for calculating a resistance at a reference time of the heater, the measurement current, and the measurement voltage. The heater resistance is obtained, the resistance at the reference time of the heater is calculated based on the measured temperature and the resistance temperature coefficient stored in the memory, and the resistance at the reference time of the heater and the heater resistance are calculated. The power supply apparatus includes an indexing unit that determines a degree of deterioration of the heater.
According to the present invention, it is possible to determine the degree of deterioration of the heater simply by obtaining the resistance of the heater at the reference time from the resistance temperature coefficient of the heater, and comparing this with the heater resistance. You can foresee.

  A third invention is a semiconductor manufacturing apparatus provided with the power supply device of the first or second invention. Since the power supply device according to the first or second invention having the heater deterioration determination function is provided, it is possible to prevent the lot out of the substrate.

  According to the present invention, it is possible to predict the disconnection of the heater at an early stage and to prevent the lot out of the substrate.

The power supply device according to this embodiment will be described below.
As shown in FIG. 1, a power supply device 21 that supplies power from an AC power source (for example, commercial power source) 1 to a heater 7 includes a power receiving terminal block 2 connected to the AC power source 1 at its input end, and a heater at its output end. And a distribution terminal block 6 connected to 7. The AC power source 1 is a commercial power source having a frequency of 50/60 Hz and an AC voltage 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. Depending on the power supply device, a plurality of power adjustment thyristor circuits 5 may be prepared so that the heater 7 can be divided into a plurality of regions and power control can be performed individually.

  A secondary side of the power transformer 4 further includes a power adjustment thyristor circuit 5 as a power regulator, a power feedback unit 23, and a temperature control unit 24. The electric power transformed by the power transformer 4 is supplied to the power adjusting thyristor circuit 5 controlled by the power feedback unit 23 and applied to the heater 7 connected to the distribution terminal block 6.

  The power adjusting thyristor circuit 5 supplies power to the heater 7 based on a command from the power feedback unit 23. The power adjusting thyristor circuit 5 supplies AC power corresponding to the frequency of the control signal applied from the power feedback unit 23 to the heater 7.

  The power feedback unit 23 corrects the power fluctuation while monitoring the state of the heater 7. This power feedback unit 23 detects a voltage measurement line 17 that measures the output line voltage (heater voltage) of the power adjustment thyristor circuit 5, a current transformer 18 that measures the heater current flowing through the heater 7, and a power fluctuation. And a power feedback circuit 16. The power feedback circuit 16 that detects the power fluctuation 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. These differences become power fluctuations. In accordance with this power fluctuation, the amount of power to be supplied to the heater 7 is calculated, and the calculation result is fed back to the power adjustment thyristor circuit 5 as a power control signal. The power feedback unit 23 is connected to the temperature controller 9 via the communication line 100, receives a temperature control signal for controlling the heater temperature through communication from the temperature controller 9, and uses this power control signal as a power control signal. The corrected control signal is output to the power adjustment thyristor circuit 5.

  The temperature control unit 24 has a temperature adjustment function and a disconnection prediction function. The temperature adjustment function detects the temperature variation of the heater 7 and outputs a temperature control signal corresponding to the variation to the power feedback circuit 16 to control the temperature of the heater 7. The disconnection prediction function receives the heater voltage and heater current measured by the power feedback unit 23, and compares these three factors of the heater temperature measured by the temperature control unit 24 with the data specific to the heater 7, thereby Detect deterioration and predict disconnection.

  In order to realize the temperature adjustment function, the temperature control unit 24 includes a thermocouple 8 as a temperature sensor and a temperature controller 9 for adjusting the heater temperature. The thermocouple 8 is provided in the vicinity of the heater 7 and measures the heater temperature by the thermoelectromotive force. The thermocouple 8 is provided for each heater if the heater 7 is divided into a plurality of heaters. The temperature controller 9 obtains a temperature difference (temperature fluctuation) between the measured temperature of the heater 7 measured by the thermocouple 8 and the set temperature. The amount of electric power to be supplied to the heater 7 is calculated according to this temperature difference, and is fed back and output as a temperature control signal as a calculation result to the power adjustment thyristor circuit 5 via the power feedback circuit 16. Moreover, the temperature controller 9 outputs an alarm when temperature abnormality, heater deterioration, etc. are detected.

  In order to realize the disconnection prediction function, the temperature control unit 24 is connected to the power feedback unit 23 via the communication line 100, receives the heater voltage and the heater current measured by the power feedback unit 23, and these and the temperature control unit 24. By comparing the three elements of the heater temperature measured in step 1 with the data specific to the heater, the deterioration of the heater 7 is detected and the disconnection is predicted, and the result is used as an alarm output.

  Next, the power feedback circuit 16 and the temperature controller 9 that control the heater 7 will be specifically described with reference to FIG.

  FIG. 2 shows a case where the heater 7 is controlled by being divided into three divided heaters 7a, 7b and 7c. In response to this, three power adjusting thyristor circuits 5a, 5b and 5c are provided. Further, three current transformers 18a, 18b, 18c, three voltage measurement lines 17a, 17b, 17c, and three thermocouples 8a, 8b, 8c are provided.

  The power feedback circuit 16 includes a CPU 161, a program memory 162, a multi A / D unit 163 that converts a plurality of analog signals into digital signals, and a multi D / A unit 164 that converts a plurality of digital signals into analog signals. In addition, the CPU 161 and the CPU 90 of the temperature controller 9 are connected by the communication line 100, and communication between the CPUs is possible between the power feedback circuit 16 and the temperature controller 9.

  The power feedback circuit 16 takes the measurement voltage and measurement current (both analog signals) measured by the three current transformers 18a, 18b, and 18c and the three voltage measurement lines 17a, 17b, and 17c into the multi-A / D unit 163. The measurement voltage and measurement current are converted into digital signals and input to the CPU 161. The CPU 161 calculates the power to be supplied to the heater 7 by obtaining the measured power from these digital signals and comparing the measured power with the set power based on the power profile programmed in advance in the program memory 162. Then, the calculation result is input to the multi-D / A unit 164 and converted into an analog signal. The power feedback circuit 16 outputs the analog signal as a power control signal to the power adjustment thyristor circuits 5a, 5b, and 5c.

  In this way, feedback control is performed from the power feedback circuit 16 to the power adjustment thyristor circuit 5, and thereby fluctuations in power applied to the heater 7 are suppressed, so that stable power is supplied to the heater 7.

The power feedback circuit 16 receives a temperature control signal from the CPU 161 of the temperature controller 9 through inter-CPU communication, and the CPU 161 performs a correction operation that combines the command value of the temperature control signal with the power amount of the power control signal. The correction calculation result is converted into an analog signal by the multi-D / A unit 164, and is fed back to the power adjustment thyristor circuits 5a, 5b and 5c as a correction control signal.
Therefore, the heater 7 is supplied with the corrected power in consideration of the temperature fluctuation and the power fluctuation, so that the heater 7 is supplied with more stable power.

On the other hand, the temperature controller 9 includes a CPU 90, program memories 91 and 92, a multi A / D unit 93, and a multi D / A unit 94. The multi-A / D unit 93 converts the three measured temperatures (analog signals) measured by the thermocouples 8a, 8b, and 8c and the corresponding three set temperatures Ta, Tb, and Tc (analog signals) into digital signals. Convert to The multi D / A unit 94 converts a plurality (three) of digital signals into a plurality of analog signals. Further, a host communication unit 94 that connects the CPU 90 and CPU 161 to a host device and the like, and a DO (discrete output) output circuit 95 that outputs an alarm capable of individually starting and stopping the heaters 7a, 7b, and 7c are provided.
The program memory 91 constitutes a memory for accumulating heater resistance obtained by calculation. The program memory 92 constitutes a memory for storing the temperature coefficient of resistance for calculating the resistance of the heater at the reference time and the resistance of the heater at the reference time obtained by the calculation.

  The temperature controller 9 receives the measured temperatures measured by the thermocouples 8a, 8b, and 8c and the corresponding set temperatures Ta, Tb, and Tc by the multi A / D unit 93, and converts these analog signals into digital signals. Convert. The CPU 90 calculates a temperature difference between the digitally converted measured temperature and the set temperature. In accordance with this temperature difference, the CPU 90 calculates the amount of power to be supplied to the heater 7 by PID calculation or the like, and outputs the calculation result as a temperature control signal to the CPU 16 of the power feedback circuit 16 by inter-CPU communication. The CPU 16 of the power feedback circuit 16 converts the temperature control signal from the temperature controller 9 into an analog signal by the multi-D / A unit 164. The power feedback circuit 16 outputs this analog signal as a control signal to the power adjustment thyristor circuits 5a, 5b, and 5c. When electric power corresponding to the temperature difference is supplied to the heaters 7a, 7b, and 7c, the temperatures of the heaters 7a, 7b, and 7c change.

  Thus, the necessary number of thermocouples 8 (8a to 8c) are provided for the heater 7 (heaters 7a to 7c), the thermoelectromotive force is fed back to the temperature controller 9, and the control signal of the temperature controller 9 is sent. By outputting to the power adjusting thyristor circuit 5 via the power feedback circuit 16, the temperature of the heater 7 is kept at a predetermined temperature.

Further, the temperature controller 9 receives the measurement voltage and the measurement current from the CPU 161 of the power feedback circuit 16 by the CPU 90 by inter-CPU communication. The CPU 90 obtains the heater resistance of the heater 7 from the measured voltage and the measured current, and stores it in the program memory 91. Further, the resistance at the reference time of the heater is calculated from the measured temperature obtained by the temperature controller 9 and the resistance temperature coefficient stored in the program memory 92 and stored in the program memory 92. The CPU 90 compares the resistance (comparison determination table) of the heater 7 stored in the program memory 92 with the heater resistance stored in the program memory 91 to determine the deterioration and disconnection of the heater 7. When the CPU 90 determines that the heater has deteriorated or is disconnected, an alarm signal is output from the DO output circuit 95, and an alarm is output from a speaker (not shown) to urge that the heater 7 needs to be replaced.
The CPU 90 described above constitutes the indexing unit of the present invention.

  As described above, the power feedback circuit 16 and the temperature controller 9 cooperate with each other to monitor the deterioration of the heater 7 in real time while performing heater control in which the power fluctuation is corrected for the temperature fluctuation in real time. Yes. This heater deterioration monitoring is performed based on a prediction algorithm.

The prediction algorithm will be described below.
Here, the principle of determining the degree of deterioration of the heater 7 will be described. The resistance R of the heater 7 is, for example, when the resistance temperature coefficient ρ of the metal wire constituting the heater 7 is 1 / ° C. (at 20 ° C.) (Ω · m), the length l is 1000 m, and the wire radius is 1 mm. Since the cross-sectional area S is 3.14 × 10 ⁻⁶ (m ² ),
From R = ρ × l / S,
R (20 ° C.) = 1 (Ω · m) × 1000 (m) /3.14×10 ⁻⁶ (m ² ) = 3.185 × 10 ⁸ (Ω).

Assuming that the heater 7 deteriorates due to changes over time and the radius of the heater wire becomes 0.8 mm, the resistance R ′ of the heater 7 at this time is:
R ′ = 1 (Ω · m) × 1000 (m) / (0.0008 × 0.0008 × 3.14) (m ² ) = 4.976 × 10 ⁸ (Ω).
For this reason, it is possible to determine the degree of deterioration of the heater 7 based on the change in the actual resistance of the heater 7 with respect to the theoretical resistance of the heater 7.

FIG. 3 is a diagram showing the contents stored in the program memory 92 shown in FIG. FIG. 3 shows a case where information relating to heaters 7A and 7B that can be used as the heater 7 is stored as an example. The program memory 92 includes a unique identification number of the heater 7, a resistance temperature coefficient of the heater 7, a length of the heater 7, a cross-sectional area of the heater 7, a resistance at the time of reference of the heater 7, for example, a reference resistance at the time of manufacture. Is a memory in which one set is stored.
Note that the temperature-resistance characteristics of the heater 7 are stored in the program memory 92 and stored in a look-up table, so that the CPU 90 may not have to calculate the theoretical resistance of the heater 7.

In FIG. 3, the heater 7A, the temperature coefficient of resistance 1.00, 1.01, and 1.04 (Ω · m) when the heater 7A is heated to 20 ° C., 800 ° C., and 1000 ° C., and the heater length 1000 (M), the sectional area 4 × 10 ⁻⁶ (m ² ) of the heater 7A and the reference resistance 4.557 (Ω) at the time of manufacturing the heater 7A are stored in association with each other.

Also, heater 7B, resistance temperature coefficients 1.00, 1.01, and 1.04 when heater 7B is heated to 20 ° C., 800 ° C., and 1000 ° C., heater 7B length 1500 (m), heater 7B shows a state in which the cross-sectional area 4 × 10 ⁻⁶ (m ² ) of 7B is stored in association with the reference resistance 9.4 (Ω) at the time of manufacturing the heater 7B.

The program memory 92 may store at least a resistance temperature coefficient corresponding to the temperature of the heater 7 when monitoring the deterioration of the heater 7, but stores more resistance temperature coefficients. Also good.
In the present embodiment, the degree of deterioration of the heater 7 is determined based on a mathematical expression described later and the above information.

FIG. 4 is a flowchart for explaining a heater deterioration monitoring function of the power supply device shown in FIGS. 1 and 2. Here, the heater 7 heats an object to be processed in a processing chamber (not shown).
First, the AC voltage of the AC power source 1 is applied to the heater 7 and the heater 7 is heated to 800 ° C., for example (step S1). Specifically, when an AC voltage is applied from the AC power source 1 to the heater 7, the power feedback thyristor circuit 5 is turned on by the power feedback unit 23 and the temperature control unit 24, and the AC voltage of the AC power source 1 is set. Is converted to a voltage usable by the heater 7 with the power transformer 4 and then applied to heat the heater 7. This state is called an idle state (standby state).

Next, the CPU 90 of the temperature controller 9 sets the temperature of the heater 7 to, for example, 800 ° C., which is the measured temperature of the heater 7, based on the electromotive force signal output from the thermocouple 8 that measures the temperature of the heater 7 itself. It is determined whether or not the temperature has reached, and the determination is repeated until the temperature reaches 800 ° C. (step S2).
When the heater 7 reaches, for example, 800 ° C. (measurement temperature T ° C.), the voltage level applied to the heater 7 is measured by the voltage measurement line 17 (step S3).

  Further, the level of the current flowing through the heater 7 is measured based on the current from the current transformer 18 (step S4). The detection time until the current level is detected in step S4 including the time for detecting 800 ° C. in step S2 described above is, for example, on the order of several tens of mmsec, and is about 1 second at the maximum. A series of these steps may be repeated to acquire a plurality of detection data. When acquiring a plurality of detection data, the average value thereof is adopted.

The analog signal from the voltage measurement line 17 and the current transformer 18 is converted into a digital signal by the multi A / D unit 163 of the power feedback circuit 16, and is transmitted from the CPU 161 of the power feedback circuit 16 via the communication line 100. Input to the CPU 90 of the temperature controller 9. The analog signal from the thermocouple 8 is converted into a digital signal by the multi A / D unit 93 of the temperature controller 9 and input to the CPU 90.
Changes (deterioration, etc.) of the heater such as the heater voltage, heater current, and heater temperature described above are monitored in real time.

Next, the CPU 90 calculates the theoretical resistance R of the heater 7 at the measured temperature (T ° C.) based on, for example, the measured temperature (T ° C.) of the thermocouple 8 and the stored contents of the program memory 92 ( Step S5). The theoretical resistance R is expressed as follows: ρT (at T ° C.) is the resistance temperature coefficient at the measurement temperature, 1 is the length of the heater 7, and S is the cross-sectional area of the heater 7.
R = ρT × l / S
Can be shown.

Next, the CPU 90 calculates the actual resistance R ′ of the heater 7 based on the detection results of the voltage measurement line 17 and the current transformer 18 (step S6). The resistor R ′ has a voltage level of the heater 7 as V and a current level of the heater 7 as I.
R ′ = V / I
Can be shown.

Subsequently, the rate of change between the theoretical resistance R of the heater 7 and the actual resistance R ′ of the heater 7 is calculated (step S7). The change rate can be shown as follows.
Rate of change = (R−R ′) / R × 100 (%)

  Next, the CPU 90 determines whether or not the calculated change rate is, for example, ± 10% or more (step S8). As a result of the determination, if the rate of change is, for example, ± 10% or more, the CPU 90 instructs the DO output circuit 95 that the heater 7 needs to be replaced soon, for example, alarm # 1 from the speaker. Is output, and then the process proceeds to step S10 (step S9).

  In step S10, it is determined whether the change rate is, for example, 30% or more. As a result of the determination, if the rate of change is, for example, 30% or more, the CPU 90 promptly instructs the DO output circuit 95 that the heater 7 needs to be replaced, for example, alarm # 1 from the speaker. Outputs alarm # 2 having a different tone color, frequency, etc. (step S11).

  Subsequently, in order to make it possible to replace the heater 7 without causing the object to be processed to be defective, heating of the heater 7 is terminated before actually carrying the object to be processed into the processing chamber (step S13).

  On the other hand, if the rate of change is not, for example, ± 10% or more, and if the rate of change is not, for example, ± 30% or more, the heater 7 is continuously heated and output from the thermocouple 8 by the temperature controller 9. The power adjustment thyristor circuit 5 is turned on / off based on the electrical signal to be set and the preset temperature of the heater 7, and the idle state (standby state) is continued. Further, the information indicated by the electric signal output from the thermocouple 8 and the on / off control information of the power adjustment thyristor circuit 5 are transmitted to the host device or the like (step S12).

  As described above, the prediction algorithm according to the embodiment captures the change between the theoretical heater resistance value and the actual heater resistance value at the same temperature, and determines the degree of heater deterioration, thereby reducing the heater deterioration. If there is a need to replace the heater, the fact is notified so that the heater can be replaced. Therefore, objective judgment can be made without relying on subjective judgment based on the experience of the operator, and the heater can be replaced before disconnection. As a result, stable power control is possible.

  In the embodiment, since a commercial power source is used as a power source for heater resistance measurement, a special power source for heater resistance measurement is not required, and the configuration is simplified.

  Furthermore, using an existing temperature controller, the output is added to the power feedback circuit, and the gate control signal of the power adjustment thyristor circuit is output, so that it can be compatible with the conventional system, The system can be easily changed from the conventional system to the present system with a slight change.

  Moreover, although the heater power supply device 21 of the above-described embodiment has been described for the general case where the heater 7 heat-treats the object to be processed in the processing chamber, specifically, the heater power supply device 21 is a semiconductor manufacturing apparatus including a reaction furnace. It can be installed. The reaction furnace includes a quartz tube and a cylindrical heater that heats the quartz tube from the outside. The power supply device of the embodiment is used to heat this heater. If the power supply apparatus described above is mounted on a semiconductor manufacturing apparatus, the stability of the heater temperature can be obtained, so that a high-performance semiconductor device can be obtained.

  Further, an apparatus capable of monitoring the deterioration of the heater can be realized only by making a change to the power supply apparatus of the present embodiment to the power supply apparatus of the existing semiconductor manufacturing apparatus. In this case, it is possible to prevent the lot out of the inserted wafer in advance by monitoring the deterioration of the heater in real time, detecting in advance the disconnection due to the change of the heater over time, and giving an abnormality alarm. Further, since the degree of deterioration of the heater can be known, normal heat treatment can always be performed in the reaction furnace, and productivity can be improved without causing a lot defect of the object to be processed. In particular, the productivity of a vertical furnace that simultaneously processes a large number of wafers can be improved. In addition, since it is possible to accurately determine the deterioration of the heater, it is not necessary to prepare a spare heater and periodically replace it, so that it is possible to replace the heater as needed, and that it is disconnected within the life prediction range period after the replacement. The problem disappears.

It is a block diagram of the power supply device by embodiment. It is a block detail drawing of the principal part of the power supply device by an embodiment. It is a figure which shows the memory content of the program memory by embodiment. It is a flowchart which shows operation | movement of the power supply device by embodiment. It is a block diagram of the power supply device by a prior art example.

Explanation of symbols

1 AC power supply 7 Heater 5 Power adjustment thyristor circuit (power regulator)
8 Thermocouple (Temperature sensor)
9 Temperature Controller 16 Power Feedback Circuit 17 Voltage Measurement Line 18 Current Transformer 21 Power Supply Device 23 Power Feedback Unit 24 Temperature Control Unit 100 Communication Line

Claims (3)

In the power supply device that determines the deterioration of the heater while supplying power to the heater from the AC power supply,
A power regulator for supplying power to the heater according to a control signal from the AC power supply;
A power feedback unit for measuring a current and a voltage supplied to the heater, supplying a power control signal corresponding to the measured current and the measured voltage to the power regulator, and controlling the power regulator;
A temperature control unit capable of measuring the temperature of the heater, providing a temperature control signal corresponding to the measured temperature to the power regulator, and controlling the power regulator;
The power feedback unit and the temperature control unit are connected by a line,
During heater supply power control, a temperature control signal is sent from the temperature control unit to the power feedback unit, and the power feedback unit controls the power regulator with a correction control signal obtained by correcting the temperature control signal with the power control signal. And
At the time of heater deterioration determination, the power feedback unit sends the measurement current and the measurement voltage to the temperature control unit, and the temperature control unit calculates the heater resistance obtained based on the measurement current and the measurement voltage, A power supply apparatus characterized in that deterioration of the heater is determined based on a resistance at a reference time of the heater obtained based on a measured temperature and a resistance temperature coefficient. The temperature controller is
A memory for storing a temperature coefficient of resistance for calculating a resistance of the heater at a reference time;
The heater resistance is obtained based on the measured current and the measured voltage, the resistance at the reference time of the heater is calculated based on the measured temperature and the resistance temperature coefficient stored in the memory, and the heater reference The power supply apparatus according to claim 1, further comprising indexing means for determining a degree of deterioration of the heater based on a resistance of time and the heater resistance.   The semiconductor manufacturing apparatus provided with the power supply device of Claim 1 or Claim 2.

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