JP5293385B2 - Heat treatment system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermal treatment system, capable of reducing the capacity of power equipment for supplying power to a thermal treatment device having reactors for heat-treating a plurality of boards collectively. <P>SOLUTION: The thermal treatment system has n reactors, performing thermal treatment to the substrate (n is an integer of &ge;2), wherein m first power converters 2a, 2b are prepared for converting three-phase AC power into DC power (m is an integer &ge;2) and second power converters 41-43 are connected to these first power converters 2a, 2b, to supply power to a heater of each reactor. Controllers 5a, 5b controls the sequence of operation of each reactor so that the sum of the consumed powers in heaters 14-16 of the n reactors does not exceed the sum of maximum outputs in the m first power converters 2a, 2b. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a technical field of electric power equipment for supplying electric power to a heater of a reaction furnace in a heat treatment system in which a plurality of substrates are held in a substrate holder, carried into a reaction furnace, and collectively heat-treated.

  As one of apparatuses installed in a semiconductor manufacturing factory, there is a vertical heat treatment apparatus that heat-treats a plurality of substrates such as semiconductor wafers (hereinafter referred to as “wafers”) collectively. The vertical reactor, which is the heat treatment section of this system, controls the temperature for each normal zone, so a plurality of heaters for each zone are arranged, and a wafer boat holds a number of wafers in a shelf shape. Then, the wafer boat is carried from the opening at the lower part of the reaction furnace, the opening is closed with a lid, and a predetermined heat treatment is performed on the wafer in this state.

  The parts where power is consumed in the heat treatment apparatus include a heater, a driving part of a gas supply system, a lifting / lowering elevator of a wafer boat, a driving part of a transfer arm, and a control part. The main part is a heater. The power facility is provided in a region away from the device, and a cable is routed from here to supply power to each device.

  FIG. 12 shows an example of a system for supplying power from the conventional power equipment 1000 to the heater of the heat treatment apparatus 1001. The commercial power is distributed by a transformer as the power equipment, and the distributed power is supplied to the heater 1004 by the cable 1003. doing. As the heater 1004, five heaters are described in which the reaction furnace is divided into five zones and each zone is heated.

  By the way, the power consumption of the heater is maximum (100%) when the wafer is loaded on the wafer boat and loaded into the reactor, and when the temperature in the reactor is stable at the heat treatment temperature. It is about 30%. This is because the lid of the reaction furnace is open at the time of loading, and the inside of the reaction furnace is cooled by carrying in a cold wafer, so that the power consumption of the heater increases. On the other hand, the power consumption of the heater is small because the inside of the reactor is in a sealed atmosphere during heat treatment.

  Conventionally, the power equipment (transformer) and the reactor are connected in a 1: 1 relationship by cable, so the capacity of each power equipment is set to a size that corresponds to the maximum (100%) power consumption of the heater. There is a need to. For this reason, although the ratio of the load time to the operation time of the reactor is small, a large-capacity power equipment is required, a large installation space is required, and the cost is high.

  In the semiconductor manufacturing factory, the commercial power allocated to each power facility is a size corresponding to the capacity of the power facility, so if the capacity of the power facility for the vertical heat treatment apparatus is large, A large commercial power allocation will be required. However, the factory side is trying to save electricity, and there is a fact that such a request is unacceptable.

  Furthermore, there is a problem that the apparatus stops when a problem occurs in the power equipment. Since zone control is performed, the number of cables corresponding to the number of heaters, for example, when there are 5 zone heaters, 10 cables are connected between the power equipment and the apparatus (vertical heat treatment apparatus). As a result, the maintenance work is disturbed by the worker, and the wiring man-hours are increased, resulting in a cost increase.

  Non-patent document 1 describes the electric power equipment of the vertical heat treatment apparatus. The electric power received from the three-phase AC power source is converted into DC by a rectifier, and this DC is converted using a voltage controller provided in front of each heater of the reactor. Although a technique for improving the power factor of the heater and reducing the harmonic current by re-converting into half-wave direct current and applying it to the heater has been described, the above-mentioned problems cannot be solved.

Japan Society for Invention and Innovation Open Technical Report No. 2003-500840

  The present invention has been made under such circumstances, and an object of the present invention is to reduce the capacity of power equipment for supplying power to a heat treatment apparatus having a reaction furnace for heat treating a plurality of substrates at once. It is to provide a heat treatment system.

A heat treatment system according to the present invention is a heat treatment system provided with n (n is an integer of 2 or more) reaction furnaces that heat-treat a plurality of substrates in parallel with each other on a substrate holder.
M (m is an integer of 2 or more) first power converters for converting three-phase AC power to DC power;
A feed path in which the output terminals of the m first power converters are connected in common;
A second power conversion unit connected to the power supply path for supplying power to the heater of each reactor;
By controlling the timing of carrying the substrate holder holding the substrate into the reaction furnace, the total power consumption of the heaters of the n reactors is the sum of the maximum outputs of the m first power converters. And a control unit for controlling the operation sequence of each reactor so as not to exceed the above.

Before SL control unit, for example act of carrying a substrate holder on which the substrate is held into the reaction furnace is intended to limit the number of reactors to be performed simultaneously.

  The present invention provides m (m) for converting three-phase AC power to DC power in a heat treatment system including n reactors (n is an integer of 2 or more) that collectively heat-treat a plurality of substrates. Is an integer greater than or equal to 2), and power equipment is configured by the first power conversion unit, and on the apparatus side, a second power conversion unit for supplying power to the heater of each reactor is provided, and n reactors are provided. The operation sequence of each reactor is controlled so that the total power consumption of the heaters does not exceed the total capacity (maximum output) of the m first power converters. Therefore, since the capacity of the first power conversion unit, which is each power facility, is smaller than the maximum (100%) of the power consumption of the heater of the reactor, the power facility can be downsized, and the power facility Therefore, the commercial power required by the factory can be reduced.

It is a vertical side view which shows the whole structure of the film-forming apparatus which concerns on this Embodiment. It is a systematic diagram which shows the electric power supply system of the heat processing system provided with two or more said film-forming apparatuses. It is a circuit diagram which shows the structure of the converter and inverter provided in the electric power supply system of the said heat processing system. It is a perspective view which shows the external appearance structure of the said heat processing system. It is a block diagram which shows the structure of the apparatus control part provided in the film-forming apparatus in the said heat processing system. It is explanatory drawing which shows the operation | movement sequence of each film-forming apparatus in the said heat processing system. It is explanatory drawing which shows the operation | movement sequence in case the three film-forming apparatuses are provided in the heat processing system. It is a systematic diagram which shows the electric power supply system of the heat processing system which concerns on other embodiment. It is a systematic diagram which shows the electric power supply system of the heat processing system which concerns on other embodiment. It is a block diagram which shows the structure of the converter and step-down chopper circuit which concern on the said further another embodiment. It is a block diagram which shows the 2nd structural example of the circuit which concerns on the said further another embodiment. It is explanatory drawing which shows the structure of the conventional electric power equipment.

  FIG. 1 is a vertical side view showing an example of a vertical heat treatment apparatus to which the heat treatment system of the present invention is applied. Hereinafter, the case where the vertical heat treatment apparatus shown in FIG. 1 is configured as a film forming apparatus that performs film formation on the wafer W by supplying a film forming gas and heating the inside of the apparatus will be described. . In FIG. 1, 11 is a quartz reaction vessel formed in, for example, a vertically long cylindrical shape, and the lower end of the reaction vessel 11 is opened as a loading / unloading port (furnace port) of the wafer W to be processed. A flange portion 112 is formed integrally with the periphery of the opening 111.

  Below the reaction vessel 11 is provided a quartz lid 113 that abuts the lower surface of the flange portion 112 and hermetically closes the opening 111. A rotating shaft 114 is provided at the center of the lid 113. It is provided through. A wafer boat 115 that is a substrate holder that holds wafers W that are a large number of substrates in parallel with each other is mounted on the upper end of the rotating shaft 114. On the other hand, the lower end of the rotating shaft 114 is provided with a motor M that forms a driving unit for rotating the rotating shaft 114, and the rotating shaft 114 is surrounded by a heat retaining unit 116 disposed on the upper surface of the lid 113. Is surrounded.

  The lid body 113, the rotating shaft 114, the wafer boat 115, and the heat retaining unit 116 are moved inside and below the reaction vessel 11 by moving the lid body 113 up and down by a boat elevator (not shown) provided on the bottom surface side of the lid body 113. You can move between positions. A state where the wafer boat 115 holding the wafer W is loaded into the reaction container 11 is a loading (loading) position, and a state where the wafer boat 115 is unloaded from the reaction container 11 is a loading (unloading) position.

  An injector 117 for supplying gas to the wafer W in the reaction vessel 11 is inserted into the flange portion 112 at the lower portion of the reaction vessel 11. A gas supply source (not shown) and a gas supply source (not shown) are provided on the proximal end side of the injector 117. A gas controller 17 having an adjustment mechanism for adjusting the amount of gas supplied from the gas supply source is connected. Further, an exhaust port for exhausting the inside of the reaction vessel 11 is formed above the reaction vessel 11, and an exhaust pipe 120 is provided in the exhaust port. The exhaust pipe 120 is connected to a vacuum pump 118 that performs vacuum exhaust so that the inside of the reaction vessel 11 has a desired degree of vacuum.

  A cylindrical heat insulating material 121 is fixed on the base body 122 around the reaction vessel 11, and a heater made of, for example, a resistance heating element is provided inside the heat insulating material 121, for example, divided into a plurality of parts. ing. As described above, in this type of heat treatment apparatus 1, the number of heater divisions is, for example, four or five, but for convenience of explanation, in this example, the heaters are the lower, middle, and upper stages. It is assumed that 14 to 16 are assigned to the divided heaters in order from the first stage on the lower stage side. The heat treatment atmosphere of the wafer W is divided into three zones (upper, middle, and lower) in the vertical direction for controlling the heating, and the heaters 14 to 16 are responsible for heating each zone (divided region). It is configured as follows. And the reaction container 11, the heat insulating material 121, the heaters 14-16, etc. which were demonstrated above are equivalent to the reaction furnace of this invention.

  In the reaction vessel 11, internal temperature sensors TC1 to TC3 made of, for example, thermocouples are provided at height positions corresponding to the heaters 14 to 16, and the internal temperature sensors TC1 to TC3 are, for example, lids 113. Are disposed at the lower, middle, and upper positions of the fixing rod 13 fixed to each other.

  The heat treatment apparatus 1 performs operation control such as loading (unloading) and unloading (loading) of the wafer W into the reaction container 11, temperature control in the reaction container 11, and power supply to the heaters 14 to 16. The apparatus control part 5 for this is provided. The apparatus control unit 5 includes a computer including a CPU and a storage unit (not shown), for example. The storage unit stores the action of the heat treatment apparatus 1, that is, a wafer boat 115 in which wafers W are held in parallel in the reaction vessel 11. A program in which a group of steps (commands) relating to the control from the execution of the film forming process on the wafer W to the unloading of the wafer boat 115 from the reaction vessel 11 is recorded. This program is stored in a storage medium such as a hard disk, a compact disk, a magnetic optical disk, or a memory card, and installed in the computer therefrom.

  The heat treatment apparatus 1 according to the present embodiment constitutes a system that jointly manages the power supplied to the heaters 14 to 16 among the plurality of heat treatment apparatuses 1, so that the total of these heat treatment apparatuses 1 It is possible to level the power consumption of the power supply and suppress the maximum load of the power supply system. Hereinafter, a detailed configuration of the system will be described.

  FIG. 2 shows a heat treatment system in which, for example, two heat treatment apparatuses 1a and 1b each equipped with one reaction furnace in the apparatus share a power supply system in the same manner as the heat treatment apparatus 1 described with reference to FIG. The power supply system is shown. The heat treatment system includes, for example, two PWM converters 2a and 2b, which are first power converters connected to commercial three-phase AC power supplies 20a and 20b having a voltage of, for example, several hundred volts. Converter-side power supply paths 201 and 202 are connected to each PWM converter 2a and 2b. These merge together to form a common power supply path 203, and then connected to the apparatus-side power supply path 204 of the heat treatment apparatuses 1a and 1b. ing. And each power consumption terminal of the heat processing apparatus 1a, 1b is connected to this apparatus side electric power feeding path 204 in parallel.

  Here, since the power consumption terminals of the heat treatment apparatuses 1a and 1b have a common configuration with each other, the description thereof will be made with reference to the heat treatment apparatus 1 shown in FIG. Heaters 14 to 16 are connected to the device-side power supply path 204 via inverters 31 to 33 as second power converters, and the power supplied from the PWM converters 2a and 2b is supplied to these inverters 31 to 31. At 33, for example, the voltage is reconverted into an alternating current of several hundred volts, and then supplied to each heater 14-16.

  The inverters 31 to 33 are connected to the heater controllers 41 to 43, respectively, and can increase or decrease the power supplied to the heaters 14 to 16 based on the command values of the heater controllers 41 to 43. The heater controllers 41 to 43 are respectively connected to the above-described internal temperature sensors TC1 to TC3 provided at the height positions corresponding to the heaters 14 to 16, and each of the lower, middle and upper stages in the reaction vessel 11 is connected. The result of detecting the temperature of the zone is acquired, compared with the temperature set value acquired from the device control unit 5, and the command value having a magnitude corresponding to the deviation of the detected temperature with respect to the temperature set value is directed to the inverters 31 to 33. For example, PID control for outputting is executed.

  Further, in this example, one of the branched device side power supply paths 204 is connected to the gas controller 17 via the chopper 34, and the voltage supplied from the PWM converters 2 a and 2 b is adjusted by the chopper 34. The direct current is supplied to the gas controller 17 as it is.

  Although the main power consumption terminals of the heat treatment apparatus 1 such as the heaters 14 to 16 have been described, the power consumption terminals in the heat treatment apparatus 1 are not limited to these examples. For example, the control power of the device controller 5, the boat elevator that moves the lid 113 up and down, and the motor M that rotates the rotating shaft 114 are also connected to the device-side power supply path 204 as loads of the PWM converters 2a and 2b. The description thereof is omitted in FIGS.

  The heaters 14 to 16, the gas controller 17, the inverters 31 to 33, the heater controllers 41 to 43, and the like described with reference to FIG. 1 are almost the same as the heat treatment apparatuses 1 a and 1 b in the heat treatment system shown in FIG. It is provided in the configuration. Among these, the same components as those shown in FIG. 1 are denoted by the same reference numerals as those in FIG. 1, and the two heat treatment apparatuses 1a and 1b are distinguished by adding the suffix “a, b”.

FIG. 3 is a circuit diagram showing a configuration of each PWM converter 2a, 2b (generally indicated as PWM converter 2) and an inverter 31 (32, 33). The PWM converter 2 includes six IGBTs (Insulated Gate Bipolar). Transistor) 210 is configured as a three-phase bridge circuit. In the figure, L _{11 to} L ₃₂ are reactors, and C _{1 to} C ₄ are capacitors. Further, the inverter 31 (32, 33) is also configured as a two-phase bridge circuit including four IGBTs 310. In the figure, L ₄ is a reactor, and C _{5 to} C ₆ are capacitors.

  In the heat treatment system having the configuration described above, the capacities (allowable maximum loads) of the two PWM converters 2a and 2b are set as follows. In other words, in the present embodiment, the two PWM converters 2a and 2b and the two heat treatment apparatuses 1a and 1b are not associated with each other in a 1: 1 relationship, and the two power supplies (PWM converters 2a and 2b) are 2 in total. The power used by the heat treatment apparatuses 1a and 1b is secured.

  The power consumption of each of the heaters 14a to 16a and 14b to 16b in the two heat treatment apparatuses 1a and 1b is, for example, as described in the background art, in which a cooled unheated wafer W is carried into the reaction vessel 11. At the timing when the wafer W is loaded, it becomes the maximum, and after the wafer W is loaded, the timing after the reaction vessel 11 is sealed with the lid 113 is stabilized with power consumption smaller than the above-mentioned maximum value. As such, it varies greatly depending on the state of the heat treatment operation sequence. For this reason, by previously limiting the operation in which the loads of the heaters 14a to 16a and 14b to 16b are 100% at the same time, the total power consumption of the heaters 14a to 16a and 14b to 16b is changed to the PWM converters 2a and 2b. The capacity is not exceeded.

From the above viewpoint, in this heat treatment system including two reactors and two PWM converters 2a and 2b, the total capacity Q of the PWM converters 2a and 2b is determined by the following equation (1).
Q = (heater power consumption at 100% load) × (one reactor that allows 100% heater load simultaneously) + (stable heater power consumption) × {(total two reactors) − (One reactor that allows 100% load of the heater at the same time)} + (control power) × (a total of two heat treatment devices equipped with the reactor) + standby power (1)

  Accordingly, the 100% load of the heaters 14a to 16a and 14b to 16b, the load at the time of stabilization, and the control power (including the raising and lowering of the boat elevator, the driving of the motor M, the power consumption of the gas controllers 17a and 17b, etc.) are grasped in advance. Thus, the total capacity of the PWM converters 2a and 2b can be determined, and the capacity of each of the PWM converters 2a and 2b can be designed based on, for example, a leveled load “Q / 2”. .

  FIG. 4 is a perspective view showing the external configuration of the heat treatment system shown in FIG. 2, and the main components of the heat treatment apparatuses 1a and 1b including those that could not be explained in the longitudinal side view of FIG. The apparatus main body 101 which is a casing, the transfer port 102 where the transfer container (wafer carrier or FOUP) of the wafer W is loaded and unloaded, and the wafer W is taken out from the transfer container loaded into the apparatus main body, and the substrate holder is used. A wafer transfer means (not shown), which is a substrate transfer means for mounting wafers W on a wafer boat 115, and the above-described reaction furnace (reaction vessel 11, heat insulating material 121, heaters 14-16, etc.) are provided. . In this example, one reaction furnace is provided in one apparatus (vertical heat treatment apparatus). However, as will be described later, a plurality of reaction furnaces may be provided in one apparatus.

  FIG. 4 also shows an image of a distribution area and a cable as a feeder line, in which 205 is a coupler that superimposes the outputs of two PWM converters 2a and 2b, and 206 is a common cable ( It is a distributor that distributes the electric power sent from the common power supply path 203) to the heat treatment apparatuses 1a and 1b.

  Further, as shown in FIG. 2, the apparatus control unit 5a of the heat treatment apparatus 1a and the apparatus control unit 5b of the heat treatment apparatus 1b are connected by a signal cable 50 so that they can communicate with each other. These device control units 5a and 5b (corresponding to the device control unit 5 described in FIG. 1) are configured by a computer as described above, and a CPU (Central Processing Unit) 51a (51b) as shown in FIG. , A recipe storage unit 52a (52b) for storing a recipe describing a processing procedure for performing a film forming process as a heat treatment on the wafer W, and a wafer boat into the reaction vessel 11 in its own heat treatment apparatus 1a (1b) 115 includes a timing determination unit 54a (54b) that determines the timing of loading (loading) 115 and a communication unit 53a (53b) for communicating with another heat treatment apparatus 1b (1a).

  As described above, the heat treatment system according to the present example needs to operate the two heat treatment apparatuses 1a and 1b so that the loads on the heaters 14a to 16a and 14b to 16b do not become 100% at the same time. The operation of the one heat treatment apparatus 1a (1a) is controlled by the timing judgment unit 54a (54b) of the one heat treatment apparatus 1a (1b) based on the operation state of the other heat treatment apparatus 1b (1a). Yes.

  Here, the state where the loads of the heaters 14 a to 16 a and 14 b to 16 b become 100% is when the wafer W is loaded into the reaction container 11. The reason is that since the cold wafer W is loaded into the reaction vessel 11 and the opening 111 of the reaction vessel 11 is open, control is performed to maximize the power supplied to the heater. On the other hand, after the temperature of the wafer W is stabilized after loading, the loads on the heaters 14a to 16a and 14b to 16b are about 30%, for example.

  Therefore, the timing controller 54a (54b) of one heat treatment apparatus 1a (1b) inquires about the operation status of the other heat treatment apparatus 1b (1a) via the communication unit 53a (53b), and the other heat treatment apparatus 1b (1a). If the wafer W is not loaded into the reaction vessel 11, the wafer W loading operation is permitted. Further, since there is a case where the temperature rise is started up to the temperature at the time of processing before the temperature of the wafer W is stabilized after loading, in this case, the heat treatment apparatus performing the temperature raising process after the wafer W is loaded. The loading operation of the wafer W may be permitted on the condition that 1a and 1b are not present.

  Immediately after the loading of the wafer W is completed, the load on the heaters 14a to 16a (14b to 16b) is still large. For example, after the loading of the wafer W is completed, the load may be permitted after a certain time has elapsed. Good. About a series of subsequent operation | movement, CPU51a (51b) reads a recipe from the recipe storage part 52a (52b), and heater controller 41a-43a (41b-) of heater 14a-16a (14b-16b) which takes charge of each zone. The temperature command value is output to 43b), and the control signal of the gas controller 17a (17b) is output.

  2 and 3 control the operation of the two PWM converters 2a and 2b according to the operating state of the heat treatment apparatuses 1a and 1b, and the heat treatment apparatus according to the operating state of the PWM converters 2a and 2b. It is a system control unit that is a host computer that controls the operation of 1a and 1b. For example, the system control unit 6 outputs a preset rated voltage as the set voltage of each PWM converter 2a, 2b. Further, for example, when one of the PWM converters 2a and 2b is abnormal and stopped, the power consumption on the heat treatment apparatuses 1a and 1b is reduced according to the power that can be supplied from the remaining PWM converters 2a and 2b. As described above, it has a function of issuing a command for adjusting the operation of the heat treatment apparatuses 1a and 1b.

  The operation of the heat treatment system described above will be described. First, a series of operations executed in each apparatus will be described. When a transfer container for the wafer W is placed on the carry-in port 102, the transfer container is taken into the apparatus main body 101 and is removed from the transfer container by the wafer transfer means. The wafer W is transferred to the wafer boat 115. When the transfer of the wafer W is completed, the lid 113 is raised by the boat elevator to carry the wafer boat 115 into the reaction vessel 11, and the opening 111 of the reaction vessel 11 is closed (loaded) by the lid 113.

  Then, after the inside of the reaction vessel 11 is evacuated by the vacuum pump 118, the atmosphere in the reaction vessel 11 and the wafer W are heated by the heaters 14-16 while supplying the film forming gas from the injector 117, When the set temperature is reached and the temperature of the wafer W is stabilized, the process is executed as it is.

  When the process is performed for a predetermined time, heating by the heaters 14 to 16 is stopped, the temperature of the wafer W and the reaction container 11 is lowered, the lid 113 is lowered, and the wafer boat 115 is unloaded from the reaction container 11. When unloading of the wafer boat 115 is completed, the transfer of the wafer W from the wafer boat 115 to the transfer container is executed, and the transfer container is transferred to the transfer port 102 through a path opposite to that at the time of transfer, and a series of operations is completed.

  Here, the series of operations (A1 to A5) of the heat treatment apparatus 1a described above are described on the upper side of FIG. 6, and the heat treatment apparatus 1b is also described on the lower stage of the figure (B1 to B5). In FIG. 6, the horizontal direction is the time axis. Therefore, in this example, the heat treatment apparatuses 1a and 1b are not simultaneously loaded, but when the heat treatment apparatus 1b inquires the heat treatment apparatus 1a to start loading, If the time is during the loading operation, the apparatus control unit 5b of the heat treatment apparatus 1b waits until the loading of the heat treatment apparatus 1a is completed, and starts loading in the heat treatment apparatus 1b after this operation is completed.

  At this time, regarding the supply of power to the heat treatment apparatuses 1a and 1b, commercial three-phase AC power is converted into DC power by the PWM converters 2a and 2b and output to the converter-side power supply paths 201 and 202, respectively. The These DC powers are superposed by the coupler 205 and supplied to the heat treatment apparatuses 1a and 1b via the common power supply path 203, the distributor 206, and the apparatus side power supply path 204.

  In this example, the command value of the output voltage of each PWM converter 2a, 2b is output from the system control unit 6 described above, and each PWM converter 2a, 2b receives the received voltage command value and the voltage detection value of the voltage sensor 61. Based on the deviation, a timing signal for controlling the ignition timing of each IGBT 210 of the three-phase bridge circuit, that is, the phase of each phase is output. For this reason, when the power consumed on the heat treatment apparatuses 1a and 1b increases, the voltage of each converter-side power supply path 201 and 202 tends to decrease, and therefore the output voltage of each PWM converter 2a and 2b also tends to decrease. A timing signal (control signal) is output so that the on-time of each transistor of the three-phase bridge circuit is lengthened, whereby the DC voltage supplied to each heat treatment apparatus 1a, 1b is kept constant.

  When an abnormality occurs such that one of the PWM converters 2a and 2b stops due to a failure, the system control unit 6 outputs a signal indicating that the abnormality has occurred to each of the heat treatment apparatuses 1a and 1b. In each of the heat treatment apparatuses 1a and 1b, based on recipe information for the occurrence of an abnormality in the power supply system stored in advance in the recipe storage units 52a and 52b, for example, a rise from the loading time when the power consumption is maximized to the process processing temperature. One PWM converter 2a, 2b can supply power, for example, by reducing the temperature speed or reducing the number of wafers W loaded into the reaction vessel 11 to reduce the load on the heaters 14a-16a, 14b-16b. After the power consumption of each heat treatment apparatus 1a, 1b is reduced to a certain level of load, the operation of both apparatuses 1a, 1b is continued.

Here, for example, when the power consumption of each heat treatment apparatus 1a, 1b is reduced by slowing the temperature rise speed, each heat treatment apparatus 1a, 1b corresponds to the power that can be supplied by one PWM converter 2a, 2b. As described above, a recipe for slowing the heating speed of the wafer W is stored in advance. When the system control unit 6 detects that an abnormality has occurred in any of the PMW converters 2a and 2b, a signal to that effect is output from the system control unit 6 to each of the heat treatment apparatuses 1a and 1b. As a result, in each of the heat treatment apparatuses 1a and 1b, a new recipe is selected, and the temperature increase speed of the wafer W is slowed based on the recipe, thereby continuing the operation within the range of power restrictions.

  In the example shown in FIG. 2, two PMW converters 2a and 2b and two heat treatment apparatuses 1a and 1b are shown. Generally, m PMW converters 2 (m is an integer of 2 or more) When there are n devices 1 (n is an integer of 2 or more), for example, the temperature increase speed is adjusted as follows. Each heat treatment apparatus 1 has a plurality of types of recipes for slowing the heating rate of the wafer W so as to match the power that can be supplied by the PWM converter 2 in which the maximum value of the total power consumption of all the heat treatment apparatuses 1 remains. ˜k (integers where 1 ≦ k ≦ m−1) PWM converters 2 are stored in association with each stopped case.

  These recipes can be supplied from, for example, the identification code of the recipe itself, the heating speed of the wafer W stored in the recipe, the number of stopped PWM converters 2 or the number of active (m−k) PWM converters 2. The maximum power is stored in association with information for selecting a recipe. When an abnormality occurs in the PWM converter 2, the system control unit 6 selects a recipe in accordance with the number of PWM converters 2 in which an abnormality has occurred (or the number of PMW converters 2 that continue to operate). A signal indicating information is output. As a result, a new recipe is selected in each heat treatment apparatus 1, and the temperature rising speed of the wafer W is slowed based on this recipe, and thereby within the range of power that can be supplied by the PWM converter 2 that continues to operate. Operation at will continue.

In addition, each heat treatment apparatus 1 directly acquires a signal indicating that an abnormality has occurred from the PWM converter 2 without using the system control unit 6, and stores a recipe stored in advance in association with the number of PWM converters 2 in which an abnormality has occurred. As a result, the temperature raising speed may be slowed down so that the total power consumption of the heat treatment apparatus 1 remains within the range of power that can be supplied by the PWM converter 2.
In the above description, the example in the case of slowing the temperature increase rate of the wafer W has been mainly described. However, in the case of reducing the number of wafers W loaded into each heat treatment apparatus 1, the same procedure as in each of the above examples is used. The power consumption of the heat treatment apparatus 1 can be reduced.

  The heat treatment system according to the present embodiment has the following effects. Heat treatment provided with n reactors (reaction vessel 11, heat insulating material 121, heaters 14 to 16, etc.) (n is an integer of 2 or more, n = 2 in this example) for performing heat treatment on a plurality of wafers W at once. In the system, m (m is an integer of 2 or more, m = 2 in this example) PWM converters 2a and 2b for converting three-phase AC power to DC power constitute a power facility and a heat treatment apparatus 1a. On the 1b side, inverters 31 to 33 for supplying electric power to the heaters 14 to 16 of each reactor are provided, and the total power consumption of the n reactors 14 to 16 is m PWM converters 2a and 2b. The operation sequence of each reactor is controlled so as not to exceed the total capacity (maximum output). Therefore, the capacity of the PWM converters 2a and 2b, which are each power equipment, is smaller than the maximum power consumption (100%) of the reactors 14 to 16, so that the power equipment can be downsized. Since the capacity of the power facility is reduced, the commercial power required for the factory can be reduced. And since the capacity is reduced, the installation space can be reduced.

In addition, since the power supply system of the heat treatment apparatuses 1a and 1b is made redundant by the two PWM converters 2a and 2b, as described above, when one of the PWM converters 2a and 2b is abnormal and stopped. In addition, the operation of the heat treatment system can be continued by reducing the load on the heaters 14a to 16a and 14b to 16b of the heat treatment apparatuses 1a and 1b.
Further, the PWM converters 2a and 2b and the heat treatment apparatuses 1a and 1b are not associated with 1: 1, and the power consumption terminals of the heat treatment apparatuses 1a and 1b are connected in parallel to the common apparatus-side power supply path 204. As a result, the number of cables such as the common power supply path 203 that are routed from the area away from the apparatus is two. For this reason, it contributes to the improvement of workability | operativity at the time of a maintenance work etc. and cost reduction compared with the case where 10 cables demonstrated by background art are routed.

  The number of heat treatment apparatuses to which this heat treatment system can be applied (corresponding to “the number of reactors” in the claims) is not limited to two, and may be three or more. In this case, for example, two 100% loads of the heaters 14 to 16 may be allowed, or only one may be allowed. FIG. 7 shows a case where, for example, a system including three heat treatment apparatuses 1a to 1c allows 100% load up to two.

  As for timing control of each apparatus, for example, similarly to the case described in the above-described embodiment, communication is performed between the apparatus control units of the respective heat treatment apparatuses 1a to 1c to determine the load start timing. Good. That is, when the heat treatment apparatus 1c is going to load from now on, the other heat treatment apparatuses 1a and 1b are inquired. If both of the heat treatment apparatuses 1a and 1b are in the loading operation at that time, the heat treatment apparatus 1c It is possible to wait until the loading of the heat treatment apparatuses 1a and 1b is completed, and to start loading in the heat treatment apparatus 1c after this operation is completed.

Here among the three of the heat treatment apparatus 1 a to 1 c, when allowing 100% load only one has two PWM converter 2a, the capacity to _{Q 1} Total 2b by the following equation (2) It is determined.
Q ₁ = (heater power consumption at 100% load) × (one reaction furnace allowing 100% load of the heater at the same time) + (stable heater power consumption) × {(total three reactors) -(One reactor that allows 100% load of the heater at the same time)} + (control power) × (total of three heat treatment apparatuses equipped with the reactor) + standby power (2)

When two devices are allowed, the total capacity Q2 of the _two PWM converters is determined by the following equation (3).
Q ₂ = (heater power consumption at 100% load) × (two reaction furnaces that allow 100% load of the heater at the same time) + (stable heater power consumption) × {(total three reactors) -(2 reactors allowing 100% load of the heater at the same time)} + (control power) x (3 heat treatment devices equipped with the reactor) + reserve power (3)

The example is connected the heat treatment apparatus 5 cars, capacity Q ₃ of the sum of the two PWM converter when simultaneously load up to two can be tolerated is determined by the following equation (4).
Q ₃ = (heater power consumption at 100% load) × (two reaction furnaces allowing 100% load of heaters simultaneously) + (stable power consumption of heaters) × {(total five reactors) -(2 reactors that allow 100% load of the heater simultaneously)} + (control power) x (total of 5 heat treatment devices equipped with the reactor) + reserve power (4)

  Here, the number of PWM converters 2 is not limited to two but may be three or more. In each of the above examples, the case where the number of PWM converters 2 is equal to or less than the number of heat treatment apparatuses 1 is illustrated, but the number of PWM converters 2 may be larger than the number of heat treatment apparatuses 1. For example, even when four 50 kVA PWM converters 2 are used and three heat treatment apparatuses 1 with a maximum power consumption of 100 kW are operated, the total power consumption of the three heat treatment apparatuses 1 is the capacity of four PWM converters 2. The present invention is effective in the case of controlling the operation sequence of each heat treatment apparatus 1 so as not to exceed the total of (maximum output). The capacities of the plurality of PWM converters 2 do not have to be the same.

  In the above-described example, the timing at which the loading of the wafer W is started (timing when the load on the heaters 14 to 16 becomes 100%) is determined by communication between the apparatus control units 5a and 5b of the heat treatment apparatuses 1a and 1b. The host computer (for example, the system control unit 6 shown in FIG. 2) is configured so as to grasp the operation status of each device 1a, 1b, and when each device 1a, 1b carries in the wafer W, the host computer You may make it go for permission.

  FIG. 8 shows, for example, two reactors 10a and 10b (and inverters 31a to 33a, 31b to 33b, which are auxiliary equipment) in the apparatus main body 101 on one side of the heat treatment apparatuses 1a and 1b illustrated in FIG. The heat processing apparatus 1d provided with heater controllers 41a-43a, 41b-43b, gas controllers 17a, 17b, etc. is shown. Also in this example, the two PWM converters 2a and 2b and the two reactors 10a and 10b are not associated 1: 1, but the two reactors 10a are provided by two power sources (PWM converters 2a and 2b). It is possible to apply the heat treatment system of the present invention that secures a power consumption of 10b.

  Further, as shown in the heat treatment apparatuses 1e and 1f shown in FIG. 9, the power supplied to the heaters 14a to 16a and 14b to 16b of each reactor is not limited to the above-described example of AC power, but is DC power. You may supply. In this example, for example, commercial three-phase AC power received at 200V is boosted to 600V DC power by the PWM converters 2a and 2b, and the high-voltage choppers 71a to 73a and 71b to 71b, which are second power converters, are used. The voltage is reduced to 100V DC power and supplied to the heaters 14a to 16a and 14b to 16b. By supplying power in a DC state to the power consuming terminal, it is possible to suppress the occurrence of power factor loss.

  In this case, the step-down choppers 71a to 73a and 71b to 73b are, for example, direct current applied to the heaters 14 (15 and 16) as generally shown as the step-down chopper 71 (72 and 73) in the block diagram of FIG. High-precision power control is possible by finely adjusting the duty ratio of pulse modulation in the step-down chopper circuit 701 by the power control unit 702 while monitoring the current value and voltage value of the power with the current sensor 703 and the voltage sensor 704, respectively. It has become.

  Further, in the example shown in FIGS. 9 and 10, as shown in FIG. 11, an inverter unit 70 is provided between the step-down chopper 71 (72, 73) and the heater 14 (15, 16), and the step-down chopper 71 (72, 72) is provided. 73) by periodically reversing the direction in which the direct current supplied from 73) flows, for example, for each process, several times a day, or several days, for example, a heater 14 (15, 16 made of a resistance heating element). ) May be suppressed. In FIG. 11, the step-down chopper circuit 701 is extracted from the step-down chopper 71 (72, 73) shown in FIG.

  In the example shown in FIG. 11, the inverter unit 70 is configured as a two-phase bridge circuit including, for example, four IGBTs 705 to 708. In this example, the IGBTs 705 and 708 are turned on and the IGBTs 706 and 707 are turned off. The current flows through the heater 14 (15, 16) in the direction of “A → B”, and the current flows in the direction of “B → A” by turning on the IGBTs 706 and 707 and turning off the IGBTs 705 and 708. . By periodically switching the flow direction of such current, the flow direction of electrons in the heaters 14 (15, 16) is periodically reversed, and accordingly, for example, metal atoms constituting the resistance heating element Since the diffusion direction is reversed, the progress of electromigration in each heater 14 (15, 16) can be suppressed as compared with, for example, a case where a current is continuously supplied in the same direction.

  In each of the above-described embodiments, the example in which the power received from the three-phase AC power source is converted into the DC power by the PWM converter 2 (first power conversion unit) has been described, but the present invention is not limited to the example of the three-phase AC power. The present invention can also be applied to AC power received by other methods.

W Wafer 1, 1a to 1f
Heat treatment apparatus 11 Reaction vessel 115 Wafer boat 14-16 Heater 17 Gas controller 2, 2a, 2b
PWM converter 20a, 20b
Three-phase AC power supply 31-33 Inverter 41-43 Heater controller 5 Device control unit 6 System control unit

Claims (2)

In a heat treatment system including n (n is an integer of 2 or more) reaction furnaces for performing heat treatment on a plurality of substrates held in parallel with each other on a substrate holder,
M (m is an integer of 2 or more) first power converters for converting three-phase AC power to DC power;
A feed path in which the output terminals of the m first power converters are connected in common;
A second power conversion unit connected to the power supply path for supplying power to the heater of each reactor;
By controlling the timing of carrying the substrate holder holding the substrate into the reaction furnace, the total power consumption of the heaters of the n reactors is the sum of the maximum outputs of the m first power converters. And a control unit that controls a sequence of operation of each reactor so as not to exceed the above. Thermal processing system of claim 1 wherein the control unit, characterized in that operation of transferring the substrate holder on which the substrate is held into the reaction furnace is intended to limit the number of reactors to be performed simultaneously.

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