CN102403195A - Longitudinal Type Heat Treatment Apparatus And Control Method Thereof - Google Patents

Abstract

Provided are a vertical heat treatment apparatus capable of converging the temperature in a processing container to a target temperature with high precision and shortening the converging time, and a control method thereof. The heat treatment device (1) has: a furnace body (5), a heater (18A) arranged on the inner peripheral surface of the furnace body (5), a processing container (3) arranged in the furnace body (5), a furnace body ( 5) The cooling medium supply blower (53), the cooling medium exhaust blower (63) and the temperature sensor (50) arranged in the processing container (3). A signal from a temperature sensor (50) is sent to a heater output calculation unit (51a) of a control device (51). In the heater output calculation unit (51a), the temperature in the heater (18A) only is determined based on the set temperature (A) obtained by the set temperature determination unit (51c) and the temperature from the temperature sensor (50). Heater output during temperature adjustment. A blower output computing unit (51b) generates blower output based on heater output.

Description

Vertical heat treatment device and its control method

technical field

The invention relates to a vertical heat treatment device and a control method thereof.

Background technique

In the manufacture of semiconductor devices, various heat treatment apparatuses are used to perform heat treatments such as oxidation, diffusion, CVD, and annealing on a target object such as a semiconductor wafer. As one of them, there is known a vertical heat treatment apparatus capable of heat treating a plurality of sheets at a time. This vertical heat treatment apparatus includes: a processing container made of quartz, which has an opening in the lower part; a cover, which opens and closes the opening of the processing container; a plurality of objects to be processed are held at intervals; and a furnace body is provided around the processing container and includes a heater for heating the object to be processed carried in the processing container.

In addition, as a vertical heat treatment apparatus, a device equipped with a blower for blowing air into the furnace body including a heater to forcibly air-cool the processing container has also been proposed (for example, refer to Japanese Patent Application Laid-Open No. 2002-305189 Bulletin). The air blower is used to cool the wafer and the processing container rapidly after the heat treatment is completed.

In addition, as the heat treatment, there is heat treatment in a low temperature range such as 100 to 500° C., such as when a film with a low dielectric constant is formed on a wafer. In the case of heat treatment in this low-temperature range, how to rapidly raise and converge the temperature to a predetermined heat treatment temperature becomes a problem. As a heat treatment apparatus for low temperature, a heat treatment apparatus having a processing chamber made of metal without using a processing container made of quartz has been proposed in order to improve thermal responsiveness. On the other hand, when attachments such as reaction products and by-products are generated during heat treatment, a processing container made of quartz that is easy to clean and replace is required in terms of the apparatus structure. In addition, by using a heater having a high thermal insulation performance, energy saving of the apparatus can be achieved, but the controllability of the temperature in the furnace deteriorates thereby. In this case, how to rapidly raise and converge the temperature to a predetermined heat treatment temperature becomes a problem, and this is not a problem limited to the low temperature range.

Patent Document 1: Japanese Patent Laid-Open No. 2002-305189

Patent Document 2: Japanese Patent Laid-Open No. 2005-188869

Contents of the invention

The problem to be solved by the invention

However, in a vertical heat treatment apparatus having a processing vessel made of quartz, since the heat capacity of the processing vessel is large, there is a problem in that the temperature rise recovery in the low temperature range takes a long time to converge. In addition, when a highly insulating heater is used for energy saving, etc., the problem is not limited to the low-temperature range. If the convergence time in the temperature rise recovery is long, it will affect the improvement of productivity. Such a problem of long convergence time occurs not only in the temperature rising process but also in the temperature falling process or when the temperature is stabilized.

The present invention has been made in consideration of such a problem, and its object is to provide a heat treatment device and its control method that can shorten the temperature rise process, temperature drop process, or The convergence time when the temperature is stable enables the temperature in the processing container to converge to the target temperature with high precision.

solutions to problems

The present invention is a heat treatment device characterized by comprising: a furnace body; a heater disposed on the inner peripheral surface of the furnace body; a processing container disposed in the furnace body to form a space with the furnace body, and A plurality of objects to be processed are accommodated inside the processing container; a blower, which is connected to the furnace body, supplies a cooling medium to the space between the furnace body and the processing container; a temperature sensor, which detects the temperature inside or outside the processing container; and a control device, which Controlling the heater and the blower to adjust the temperature in the processing container so that the temperature in the processing container converges to a predetermined target temperature, wherein the above-mentioned control device has: a heater output calculation unit, which is based on a predetermined set temperature and a temperature from The temperature of the sensor determines the heater output when only the heater is used for temperature adjustment; and the blower output calculation unit determines the blower output based on the heater output from the heater output calculation unit.

The present invention is a heat treatment apparatus characterized in that the blower output calculation unit generates the blower output when the heater output from the heater output calculation unit is negative, and the blower output calculation unit stops when the heater output is equal to or greater than zero. Blower output.

The present invention is a heat treatment device characterized in that the blower output calculation unit generates a blower output when the slope of the heater output from the heater output calculation unit is lower than a certain threshold value, and the blower output calculation unit generates the blower output when the slope of the heater output is higher than a certain threshold value. In the case of the blower output calculation unit stops the blower output.

The present invention is a heat treatment device characterized in that the control device further includes a flow rate control calculation unit for converting the blower output from the blower output calculation unit into a cooling medium flow rate.

The present invention is a heat treatment device characterized in that the flow rate control calculation unit controls the rotational speed of the blower according to the flow rate of the cooling medium.

A control method of a heat treatment device according to the present invention is used to control the above-mentioned heat treatment device. The method is characterized in that it includes the following steps: The temperature of the heater is used to determine the heater output when only the heater is used for temperature adjustment; and the blower output is determined by the blower output calculation unit based on the heater output from the heater output calculation unit.

The present invention is a control method of a heat treatment device, characterized in that, when the heater output from the heater output calculation unit is negative, the blower output calculation unit generates the blower output, and when the heater output is equal to or greater than zero, the blower output is zero. The arithmetic unit stops blower output.

The present invention is a control method of a heat treatment device, characterized in that the blower output calculation unit generates a blower output when the slope of the heater output from the heater output calculation unit is lower than a certain threshold value, and the heater output calculation unit generates a blower output when the slope of the heater output is high. In the case of a certain threshold value, the blower output calculation unit stops the blower output.

The present invention is a control method of a heat treatment device, characterized in that it further comprises the step of: converting the blower output from the blower output calculation unit into the cooling medium flow through flow control calculation.

The present invention is a control method of a heat treatment device, characterized in that the flow control operation unit controls the rotational speed of the blower according to the flow rate of the cooling medium.

The present invention is a heat treatment device characterized by comprising: a furnace body; a heater disposed on the inner peripheral surface of the furnace body; a processing container disposed in the furnace body to form a space with the furnace body, and A plurality of objects to be processed are accommodated inside the processing container; a blower is connected to the furnace body through a cooling medium supply line, and supplies cooling medium to the space between the furnace body and the processing container; a valve mechanism adjusts the flow rate of the cooling medium supplied from the blower a temperature sensor, which detects the temperature inside or outside the processing container; and a control device, which controls the heater and the valve mechanism, and adjusts the temperature in the processing container so that the temperature in the processing container converges to a prescribed target temperature, wherein the control The device has: a heater output calculation unit, which determines the heater output when only the heater is used for temperature adjustment based on the predetermined set temperature and the temperature from the temperature sensor; The heater output of the calculation unit determines the cooling output; and the flow control calculation unit converts the cooling output from the cooling output calculation unit into the cooling medium flow rate, wherein the flow control calculation unit controls the valve mechanism according to the cooling medium flow rate.

The present invention is a heat treatment apparatus characterized in that the cooling output calculation unit generates a cooling output when the heater output from the heater output calculation unit is negative, and stops the cooling output calculation unit when the heater output is equal to or greater than zero. cooling output.

The present invention is a heat treatment device characterized in that the cooling output calculation unit generates a cooling output when the slope of the heater output from the heater output calculation unit is lower than a certain threshold value, and the cooling output calculation unit generates a cooling output when the slope of the heater output is higher than a certain threshold value. In the case of the cooling output calculation unit stops the cooling output.

The present invention is a control method of a heat treatment device, which is used to control the above-mentioned heat treatment device. The method is characterized in that it includes the following steps: The temperature of the sensor determines the heater output when only the heater is used for temperature adjustment; the cooling output is determined by the cooling output calculation unit according to the heater output from the heater output calculation unit; and the cooling output from the cooling output calculation unit is determined. The output is converted into the flow rate of the cooling medium by the flow control calculation unit, wherein the flow control calculation unit controls the valve mechanism according to the flow rate of the cooling medium.

The present invention is a control method of a heat treatment device, characterized in that the cooling output calculation unit generates a cooling output when the heater output from the heater output calculation unit is negative, and the cooling output is generated when the heater output is equal to or greater than zero. The computing unit stops the cooling output.

The present invention is a control method of a heat treatment device, characterized in that the cooling output calculation unit generates a cooling output when the slope of the heater output from the heater output calculation unit is lower than a certain threshold value, and the cooling output calculation unit generates a cooling output when the slope of the heater output is high. In the case of a certain threshold value, the cooling output calculation unit stops the cooling output.

The effect of the invention

According to the present invention, the temperature in the processing container can be accurately converged to the target temperature while shortening the convergence time in the temperature rise recovery in the low temperature range, thereby improving throughput. Alternatively, when a heater with high thermal insulation performance is used, it is possible to reduce power consumption without affecting productivity.

Description of drawings

1( a ) is a longitudinal sectional view schematically showing a heat treatment apparatus according to a first embodiment of the present invention, and FIG. 1( b ) is a view showing a control device of the heat treatment apparatus.

Fig. 2 is a diagram showing a coolant supply line and a coolant exhaust line of the heat treatment device.

(a), (b) and (c) of FIG. 3 are figures which show the control method of a heat processing apparatus.

Fig. 4 is a diagram showing a method of controlling the heat treatment device.

5 is a diagram showing a control device of a heat treatment device according to a second embodiment of the present invention.

Explanation of reference signs

w: semiconductor wafer (processed object); 1: heat treatment device; 2: heat treatment furnace; 3: processing container; 3a: furnace mouth; 5: furnace body; 16: heat insulation material; 18: heater element (heating resistor body); 18A: heater; 18B: heater drive unit; 33: space; 40: cooling medium blowout hole; 49: supply pipe; 50: temperature sensor; 51: control device; 51a: heater output calculation unit; 51b : Blower output calculation unit; 51c: Set temperature determination unit; 51e: Flow control calculation unit; 52: Coolant supply line; 53: Coolant supply blower; 53a: Inverter drive unit; 62: Coolant exhaust line ; 63: cooling medium exhaust blower; 63a: inverter drive unit.

Detailed ways

first embodiment

Next, a first embodiment of the present invention will be described with reference to the drawings. Here, Fig. 1(a) is a longitudinal sectional view schematically showing a heat treatment device of the present invention, Fig. 1(b) is a diagram showing a control device for a heat treatment device, and Fig. 2 is a diagram showing a cooling medium supply of a vertical heat treatment device. 3 (a), (b), (c) are diagrams showing a control method of a heat treatment device, and FIG. 4 is a diagram showing a control method of a heat treatment device.

In FIG. 1 , a vertical heat treatment apparatus 1 includes a vertical heat treatment furnace 2 capable of accommodating a plurality of objects to be processed at a time, such as semiconductor wafers w, and performing heat treatments such as oxidation, diffusion, and reduced-pressure CVD. This heat treatment furnace 2 is provided with: a furnace body 5 provided with a heating resistor (heater) 18A on its inner peripheral surface; The wafer w is accommodated and heat-treated. Among them, the heater 18A is constituted by a plurality of heater elements 18 as will be described later.

In addition, the furnace body 5 is supported by a bottom plate 6 in which an opening 7 for inserting the processing container 3 from below to above is formed. In addition, an unillustrated heat insulating material is provided in the opening 7 of the bottom plate 6 to cover the gap between the bottom plate 6 and the processing container 3 .

The processing container 3 is made of quartz, and has a vertically elongated cylindrical shape with its upper end closed and its lower end opened as a furnace port 3a. An outward flange 3b is formed at the lower end of the processing container 3, and the flange 3b is supported by the bottom plate 6 via a flange holding plate not shown. In addition, in the processing container 3, an introduction port (introduction port) 8 for introducing a processing gas, an inert gas, etc. The exhaust port (exhaust port). A gas supply source (not shown) is connected to the introduction port 8, and an exhaust system (not shown) equipped with a vacuum pump is connected to the exhaust port ^. Pa or so.

A cover body 10 for closing the furnace opening 3 a of the processing container 3 is provided below the processing container 3 so as to be movable up and down by an elevating mechanism not shown. On the upper part of the cover body 10 is placed an insulating cylinder 11 as a heat preservation unit for the furnace opening, and on the upper part of the insulating cylinder 11 is placed a quartz plate 12, and the quartz plate 12 is mounted at a predetermined interval in the vertical direction. A holding tool for a plurality of, for example, about 100 to 150 wafers w with a diameter of 300 mm. The cover body 10 has a rotation mechanism 13 for rotating the plate 12 around its axis. The plate 12 is carried out (unloaded) from the processing container 3 into the loading area 15 below by the downward movement of the cover body 10, and the plate 12 is carried in (loaded) by the upward movement of the cover body 10 after the transfer of the wafer w. ) into the processing container 3.

The above-mentioned furnace body 5 has a cylindrical heat insulating material 16 and a groove-like frame portion 17 formed in multiple stages along the axial direction (up and down direction in the illustrated example) on the inner peripheral surface of the heat insulating material 16. A heater element (heater wire, heating resistor) 18 is disposed on each frame portion 17 . The heat insulating material 16 includes, for example, silica, alumina, or inorganic fibers containing silicate alumina. The heat insulating material 16 is divided into two longitudinally, so that the assembly of the heater element and the assembly of the heater can be easily performed.

A pin member (not shown) is disposed in the heat insulating material 16 to hold the heater element 18 in such a manner that it moves radially at appropriate intervals and does not come off or fall out of the frame portion 17 . heater element 18. On the inner peripheral surface of the above-mentioned cylindrical heat insulating material 16, annular grooves 21 concentric with the heat insulating material 16 are formed in multiple stages at predetermined intervals along the axial direction. The above-mentioned annular frame portion 17 continuous in the circumferential direction is formed between the groove portions 21 . Between the upper part and the lower part of the heater element 18 in the above-mentioned groove part 21 and the inner wall of the groove part 21 and the heater element 18, there is a sufficient gap that can allow the thermal expansion and contraction of the heater element 18 and the movement in the radial direction. When forced cooling is performed through these gaps, the cooling medium detours to the back surface of the heater element 18 so that the heater element 18 can be effectively cooled. Furthermore, air, nitrogen or water are conceivable as such cooling media.

The respective heater elements 18 are joined by a connection plate, and the heater element 18 positioned at the end side is connected to the external heater drive unit 18B via terminal plates 22a, 22b provided to penetrate in the radial direction. Insulation material 16.

As shown in FIG. 1 , in order to maintain the shape of the heat insulating material 16 of the furnace main body 5 and reinforce the heat insulating material 16 , the outer peripheral surface of the heat insulating material 16 is covered with a metal outer skin (casing) 28 made of, for example, stainless steel. In addition, in order to suppress the influence of heat on the outside of the furnace main body 5 , the outer peripheral surface of the sheath 28 is covered with a water-cooling jacket 30 . On the top of the heat insulator 16 is provided an upper heat insulator 31 covering it, and on the upper portion of the upper heat insulator 31 is provided a stainless steel top plate 32 covering the top (upper end) of the sheath 28 .

In addition, as shown in FIG. 1 and FIG. 2 , in order to rapidly cool down the wafer after the heat treatment to realize rapid processing and increase productivity, a space between the furnace body 5 and the processing container 3 is provided in the furnace body 5 . A heat removal system 35 that discharges the ambient air in the space 33 to the outside, and a forced cooling medium unit 36 that introduces a cooling medium at a normal temperature (20 to 30° C.) into the space 33 to forcibly cool it. The heat removal system 35 includes an exhaust port 37 provided on the upper part of the furnace body 5, and the exhaust port 37 is connected with a cooling medium exhaust line 62 that exhausts the cooling medium in the space 33 and has a flow sensor 62a.

And, the forced cooling medium unit 36 has: an annular flow path 38, which is formed in a plurality of height directions between the heat insulating material 16 and the outer skin 28 of the furnace body 5; The thermal material 16 blows the cooling medium obliquely toward the center of the heat insulating material 16 from each annular flow path 38 to generate eddy currents in the circumferential direction of the space 33 . The annular flow path 38 is formed by affixing a strip-shaped or annular heat insulating material 41 to the outer peripheral surface of the heat insulating material 16 or by cutting the outer peripheral surface of the heat insulating material 16 into a ring shape. The cooling medium blowout hole 40 is formed in the frame portion 17 between the heater elements 18 adjacent up and down in the heat insulating material 16 and penetrates the frame portion 17 radially inwardly and outwardly. As a result, the cooling medium blowout hole 40 is provided in the frame portion 17 , and the cooling medium can be sprayed into the above-mentioned space 33 without interfering with the heater element 18 .

In addition, although an example in which a strip-shaped heating resistor is used as the heater element 18 and housed in the frame portion 17 has been described, the heater element 18 is not limited to this structure, and heating elements of various other structures can also be used. In addition, although the example in which the cooling medium is blown out from the cooling medium blowing holes 40 is described to generate eddy currents in the space 33 , it is not necessary to generate the eddy currents by blowing the cooling medium through the cooling medium blowing holes 40 .

A common supply pipe 49 for distributing and supplying the cooling medium to each annular flow path 38 is provided on the outer peripheral surface of the above-mentioned outer skin 28 along the height direction. connection port. The supply pipe 49 is connected with a cooling medium supply line 52 for supplying the cooling medium and having a flow sensor 52a.

In addition, a temperature sensor 50 for detecting the temperature in the processing container 3 is provided in the processing container 3, and a detection signal from the temperature sensor 50 is sent to the control device 51 via a signal line 50a. In addition, the temperature sensor 50 does not have to be provided in the processing container 3 , and the temperature sensor 50 may be provided in the space 33 between the furnace body 5 and the processing container 3 , or in both.

In addition, as shown in FIGS. 1 and 2 , the coolant supply line 52 and the coolant exhaust line 62 each independently constitute an open system coolant supply/exhaust line. Among them, a cooling medium supply blower 53 having an inverter drive unit 53 a is provided in the cooling medium supply line 52 .

In addition, a damper 56 is provided on the inlet side of the cooling medium supply blower 53 , and an orifice valve 54 and a butterfly valve 55 are arranged on the outlet side of the cooling medium supply blower 53 . The damper 56 on the inlet side of these cooling medium supply blowers 53 and the orifice valve 54 and the butterfly valve 55 on the outlet side of the cooling medium supply blower 53 can be adjusted freely. Line side valve mechanism 54A.

In addition, a coolant exhaust blower 63 having an inverter drive unit 63 a is provided in the coolant exhaust line 62 .

Furthermore, a butterfly valve 66 and an orifice valve 67 are provided on the inlet side of the coolant exhaust blower 63 , and an orifice valve 64 and a butterfly valve 65 are arranged on the outlet side of the coolant exhaust blower 63 . The butterfly valve 66 and the orifice valve 67 on the inlet side of these cooling medium exhaust blowers 63 and the orifice valve 64 and the butterfly valve 65 on the outlet side of the cooling medium exhaust blowers 63 can be adjusted freely, and the cooling medium exhaust blowers 63 The butterfly valve 66 and the orifice valve 67 on the inlet side, and the orifice valve 64 and the butterfly valve 65 on the outlet side of the coolant exhaust blower 63 constitute a coolant exhaust line side valve mechanism 64A.

Next, the control device 51 connected to the temperature sensor 50 will be described in detail.

The temperature sensor 50 is installed in the processing container 3 as described above to detect the temperature in the processing container 3, and the temperature sensor 50 may be installed in the space 33 between the furnace body 5 and the processing container 3 to detect the temperature indirectly. The temperature in container 3.

A detection signal detected by the temperature sensor 50 is sent to the control device 51 via the signal line 50a. This control device 51 is used to shorten the convergence time to a predetermined target temperature and to approach the target temperature with high precision during a temperature rise process, a temperature drop process, or temperature stabilization in a low temperature range of, for example, 100° C. to 500° C. ((b of FIG. 1 ). )).

That is, the control device 51 has a heater output calculation unit 51a for determining heating when temperature adjustment is performed using only the heater 18A based on the set temperature determined in advance in the set temperature determination unit 51c and the temperature from the temperature sensor 50. and a blower output calculation unit 51b that determines the blower output based on the heater output from the heater output calculation unit 51a.

Here, for example, during the temperature rise process, the temperature in the processing container 3 is converged to the target temperature with respect to a predetermined target temperature, so the set temperature A is determined in the set temperature determination unit 51c (see (a) and (b) of FIG. 3 . ), (c)). And the set temperature A determined by this set temperature determination part 51c is sent to the heater output calculation part 51a.

In addition, the heater output obtained by the heater output calculation unit 51 is sent to the heater driving unit 18B, and the heating is driven and controlled by the heater drive unit 18B based on the heater output obtained by the heater output calculation unit 51 . The heater element 18 of the device 18A.

On the other hand, the blower output obtained by the blower output calculation unit 51b is sent to the inverter drive units 53a, 63a, and the cooling medium supply blower 53 and the cooling medium exhaust blower are driven and controlled by these inverter drive units 53a, 63a. 63.

Thus, the cooling medium is supplied into the space 33 between the furnace main body 5 and the processing container 3 by the cooling medium supply blower 53 and the cooling medium exhaust blower 63 .

In addition, although the example in which the cooling medium is supplied to the space 33 between the furnace body 5 and the processing container 3 by providing the cooling medium supply blower 53 and the cooling medium exhaust blower 63 has been shown, it is not limited to this, and only a cooling medium may be provided. Either one of the medium supply blower 53 and the cooling medium exhaust blower 63 supplies the cooling medium into the space 33 between the furnace body 5 and the processing container 3 . In addition, in this case, both the cooling medium supply line and the cooling medium exhaust line may be connected to the blower to constitute a closed system cooling medium supply/exhaust line. For example, when only the cooling medium supply blower 53 is provided, the inverter drive unit 53a that controls the cooling medium supply blower 53 is driven based on the blower output obtained by the blower output calculation unit 51b.

Next, the operation of the heat treatment apparatus having such a structure will be described.

First, the wafer w is placed on the plate 12 , and the plate 12 on which the wafer w is placed is placed on the thermal insulation tube 11 of the cover 10 . Thereafter, the plate 12 is carried into the processing container 3 by the upward movement of the lid body 10 .

Next, the control device 51 controls the heater drive unit 18B to operate the heater element 18 to heat the space 33 between the furnace body 5 and the processing container 3 to heat the wafer w on the plate 12 mounted in the processing container 3 . Apply the desired heat treatment.

During this period, the space 33 between the furnace main body 5 and the processing container 3 is forcibly cooled in order to increase the efficiency of the heat treatment operation as necessary, as will be described later.

In this case, first, the cooling medium supply blower 53 and the cooling medium exhaust blower 54 are operated under the control of the control device 51 . At this time, the cooling medium (20° C. to 30° C.) is introduced into the cooling medium supply line 52 , and then the cooling medium is sent out from the cooling medium supply blower 53 to the supply duct 49 .

Afterwards, the cooling medium in the supply pipe 49 enters each annular flow path 38 formed on the outside of the heat insulating material 16 of the furnace body 5 , and then the cooling medium in the annular flow path 38 passes through the cooling medium provided through the heat insulating material 16 . The blowing hole 40 blows out into the space 33 between the furnace main body 5 and the processing container 3 to forcibly cool the space 33 .

The cooling medium in the space 33 is exhausted to the outside by the cooling medium exhaust blower 63 after passing through the cooling medium exhaust line 62 and being cooled by the heat exchanger 69 .

Next, the control in the control device 51 for adjusting the temperature in the processing container 3 to converge the temperature in the processing container 3 to a predetermined target temperature T will be described in detail below with reference to (a), (b), and (c) of FIG. 3 . method.

Here, (a) of FIG. 3 is a diagram showing the set temperature A and the temperature (from the temperature sensor 50) B of the control object obtained by the set temperature determination unit 51c for a predetermined target temperature, and (b) of FIG. 3 ) is a diagram showing a first control method in the control device 51 , and (c) of FIG. 3 is a diagram showing a second control method in the control device 51 .

First, the first control method in the control device 51 will be described with reference to (a) and (b) of FIG. 3 . As shown in (a) and (b) of FIG. 3 , in order to converge to a predetermined target temperature T in the process of rising and falling in the cold temperature region, the set temperature A is obtained in the set temperature determination unit 51c of the control device 51 .

Next, the set temperature A from the set temperature determination unit 51c is input to the heater output calculation unit 51a. The heater output when temperature adjustment is performed using only the heater 18A is obtained from the temperature B.

Next, as shown in (b) of FIG. 3 , the heater output obtained by the heater output computing unit 51 a is sent to the blower output computing unit 51 b.

In the blower output computing unit 51b, when the heater output is negative, the blower output having a shape symmetrical to the heater output of the negative value is determined.

In addition, in the blower output calculation unit 51b, when the heater output becomes negative, it is only necessary to determine the blower output in a shape corresponding to the negative value of the heater output. In this case, the heater output and the blower The output does not necessarily have to have a symmetrical shape.

Next, the heater drive unit 18B drives and controls the heater 18A based on the heater output obtained by the heater output calculation unit 51 a. Simultaneously, the inverter drive units 53a, 63a perform drive control by controlling the rotational speeds of the cooling medium supply blower 53 and the cooling medium exhaust blower 63 based on the blower output obtained by the blower output calculation unit 51b.

In this way, the heater 18A is driven by the heater drive unit 18B based on the heater output obtained by the heater output calculation unit 51a, and when the heater output becomes negative, the negative value of the heater output is determined. The blower output is obtained by the blower output computing unit 51b, and the blower output is stopped when the heater output becomes equal to or greater than zero. Accordingly, it is possible to bring the temperature B of the control object close to the set temperature A with high precision and quickly converge to a predetermined target temperature.

In addition, the blower output calculation unit 51b may determine the blower output not only by using zero of the heater output as a threshold value based on the negative value, but also by setting a predetermined offset to the threshold value to determine the blower output.

Next, the second control method in the control device 51 will be described with reference to (a) and (c) of FIG. 3 . As shown in (a) and (c) of FIG. 3 , it converges to a predetermined target temperature T during the ups and downs in the low temperature range, so the set temperature is obtained in the set temperature determination unit 51c of the control device 51 a.

Next, the set temperature A from the set temperature determination unit 51c is input to the heater output calculation unit 51a. The heater output when temperature adjustment is performed with only the heater 18A is obtained.

Next, as shown in (c) of FIG. 3 , the heater output obtained by the heater output computing unit 51 a is sent to the blower output computing unit 51 b.

In the blower output calculation unit 51b, the blower output is determined so that the blower output is generated when the slope of the heater output is negative, and the blower output is stopped when the slope of the heater output is equal to or greater than zero.

Next, the heater drive unit 18B drives and controls the heater 18A based on the heater output obtained by the heater output calculation unit 51 a. Simultaneously, the inverter drive units 53a, 63a control the rotational speeds of the cooling medium supply blower 53 and the cooling medium exhaust blower 63 respectively based on the blower output obtained by the blower output calculation unit 51b.

In this way, the heater 18A is driven by the heater drive unit 18B based on the heater output obtained by the heater output calculation unit 51a, and when the gradient of the heater output is negative, the gradient of the heater output is On the negative side, the blower output is obtained by the blower output calculation unit 51b, and the blower output is stopped when the gradient of the heater output is equal to or greater than zero. Accordingly, it is possible to bring the temperature B of the control object close to the set temperature A with high precision and quickly converge to a predetermined target temperature.

In addition, the blower output calculation unit 51b can obtain the blower output not only by using the slope zero of the heater output as a threshold value depending on whether it is negative, but also by setting a predetermined offset to the threshold value.

Next, a description will be given of a specific action when the first control method is executed by the above-mentioned control device 51 or when the second control method is executed during the temperature drop in the low-temperature region with reference to FIG. 4 .

As shown in FIG. 4 , when the temperature in the processing container 3 is lowered from the current temperature of 400° C. to the target temperature of 300° C. in the temperature drop process in the low temperature region, first, the set temperature determination unit 51 c of the control device 51 Find the set temperature A in

Next, by executing the above-mentioned first control method (the control method shown in (b) of FIG. 3 ) or the second control method (the control method shown in FIG. 3( c )), the temperature B of the control object can be brought close to the set point The temperature A is fixed, and the temperature is rapidly and accurately lowered in a short convergence time until the target temperature is 300°C.

That is, as shown in FIG. 4 , when the temperature is lowered from the current temperature of 400° C. only by cutting off the heater, the temperature in the processing container 3 drops to the target temperature of 300° C. (refer to C in FIG. 4 ), but reaches The time until the target temperature of 300° C. becomes longer and the temperature in the processing container 3 drops even when the target temperature becomes lower than or equal to the target temperature, so that the temperature does not converge to the target temperature of 300° C.

On the other hand, when the heater is turned off from the current temperature of 400° C. and the blower is not controlled and operated, the temperature in the processing container 3 rapidly drops to the target temperature of 300° C. (see D in FIG. 4 ), but the Even when the target temperature becomes lower than or equal to the target temperature, the temperature inside the processing container 3 drops and does not converge to the target temperature of 300°C.

On the other hand, according to the present invention, by using the above-mentioned first control method or second control method, it is possible to bring the temperature B of the control object close to the set temperature A, and to reach the target temperature of 300°C in a short convergence time quickly and high. Cool down with precision. In addition, the temperature B of the control object can be reliably converged to the target temperature of 300°C.

In addition, this invention is not limited to each said embodiment, Various design changes are possible within the range of the summary of this invention. For example, the processing container may be formed by connecting a cylindrical branch pipe made of heat-resistant metal such as stainless steel having an introduction pipe portion and an exhaust pipe portion to the lower end, or may have a double pipe structure.

2nd embodiment

Next, a second embodiment of the present invention will be described with reference to FIG. 5 .

The second embodiment shown in FIG. 5 differs only in the configuration of the control device 51 , and the other configurations are substantially the same as those of the first embodiment shown in FIGS. 1 to 4 .

In the second embodiment shown in FIG. 5 , the same parts as those in the first embodiment shown in FIGS. 1 to 4 are denoted by the same symbols, and detailed descriptions thereof will be omitted.

As shown in FIG. 5 , the control device 15 has: a heater output calculation unit 51 a that determines the temperature of the heater only based on the set temperature determined in advance in the set temperature determination unit 51 c and the temperature in the furnace from the temperature sensor 50 . 18A heater output when temperature adjustment is performed; and a blower output calculation unit (cooling output calculation unit) 51b that determines the blower output (cooling output) based on the heater output from the heater output calculation unit 51a.

In addition, the control device 51 has a flow rate control calculation unit 51e that converts the blower output (cooling output) from the blower output calculation unit 51b into a coolant flow rate. In this case, the flow rate control computing unit 51 e converts the blower output into an appropriate cooling medium flow rate to be supplied to the space 33 between the furnace main body 5 and the processing container 3 .

In FIG. 5 , heater output computing unit 51 a determines heater output when temperature adjustment is performed by only heater 18A based on the temperature in the furnace from temperature sensor 50 . Further, the blower output is obtained by the blower output calculation unit 51b based on the heater output from the heater output calculation unit 51a.

Furthermore, the flow rate control calculation unit 51e converts the blower output obtained by the blower output calculation unit 51b into the coolant flow rate, and based on the coolant flow rate and the coolant supply line 52 and the coolant exhaust gas detected by the flow sensors 52a and 62a, The flow rate of the cooling medium on the line 62 is used to output the signal for driving the inverter. Afterwards, the inverter drive units 53a and 63a control the rotational speeds of the cooling medium supply blower 53 and the cooling medium exhaust blower 63 based on the inverter driving signal obtained by the flow rate control calculation unit 51e to control the cooling. The cooling medium flow rate of the medium supply line 52 and the cooling medium exhaust line 62 .

In this way, the blower output obtained by the blower output calculation unit 51b is converted into the flow rate of the cooling medium supplied to the space 33 between the furnace body 5 and the processing container 3 in the flow control calculation unit 51e, and is adjusted by the flow rate sensors 52a, 62a. The detected coolant flow rate is, for example, when the coolant supply line 52 and the coolant exhaust line 62 have long pipes, or when the coolant supply line 52 and the coolant exhaust line 62 have short pipes, etc., Even if the arrangement and shape of the cooling medium supply line 52 and the cooling medium exhaust line 62 of the heat treatment apparatus 1 are different, a desired amount of cooling medium can be supplied in the space 33 between the furnace body 5 and the processing container 3 .

Thereby, the temperature inside the furnace can be controlled with high precision at all times regardless of the arrangement and shape of the coolant supply line 52 and the coolant exhaust line 62 of the heat treatment apparatus 1 .

In addition, although an example in which the cooling medium blower 53 and the cooling medium exhaust blower 63 are driven and controlled based on the flow rate of the cooling medium calculated by the flow rate control calculation unit 51e is shown, the present invention is not limited to this, and the flow rate control calculation unit 51e may The cooling medium flow rate obtained is used to drive and control the cooling medium supply line side valve mechanism 54A, and the cooling medium discharge side valve mechanism 64A may be driven and controlled based on the cooling medium flow rate obtained by the flow rate control computing unit 51e. In addition, although the example in which the flow rate control calculation unit 51e converts the blower output (cooling output) to obtain the flow rate of the cooling medium and adjust the flow rate of the cooling medium from the flow sensors 52a and 62a is shown, the flow rate from the flow sensors 52a and 62a may also be used. One of the cooling medium flow to adjust.

Claims (16)

1. A heat treatment device, characterized in that, possesses: Furnace body; The heater is arranged on the inner peripheral surface of the furnace body; A processing container, which is arranged in the furnace body, forms a space with the furnace body, and accommodates a plurality of objects to be processed inside the processing container; A blower, which is connected to the furnace body, supplies cooling medium to the space between the furnace body and the processing container; a temperature sensor that detects the temperature inside or outside the processing vessel; and a control device that controls the heater and the blower to adjust the temperature in the processing container so that the temperature in the processing container converges to a predetermined target temperature, Wherein, the above-mentioned control device has: a heater output calculation unit, which determines the heater output when only the heater is used for temperature adjustment based on a predetermined set temperature and a temperature from a temperature sensor; and a blower output calculation unit, which The blower output is determined based on the heater output from the heater output computing unit. 2. The heat treatment apparatus according to claim 1, wherein: The blower output calculation unit generates a blower output when the heater output from the heater output calculation unit is negative, and stops the blower output when the heater output is equal to or greater than zero. 3. The heat treatment apparatus according to claim 1, wherein: The blower output calculation unit generates a blower output when the slope of the heater output from the heater output calculation unit is lower than a certain threshold, and stops the blower output when the slope of the heater output is higher than a certain threshold. 4. The heat treatment apparatus according to claim 1, wherein: The control device further includes a flow rate control calculation unit that converts the blower output from the blower output calculation unit into a cooling medium flow rate. 5. The heat treatment apparatus according to claim 4, wherein: The flow rate control calculation unit controls the rotation speed of the blower according to the flow rate of the cooling medium. 6. A control method for a heat treatment device, used for controlling the heat treatment device according to claim 1, the method is characterized in that it has the following steps: In the heater output calculation unit of the control device, the heater output when temperature adjustment is performed with only the heater is determined based on a predetermined set temperature and the temperature from the temperature sensor; and The blower output is determined by the blower output calculation unit based on the heater output from the heater output calculation unit. 7. The control method of the heat treatment device according to claim 6, characterized in that: The blower output calculation unit generates a blower output when the heater output from the heater output calculation unit is negative, and stops the blower output when the heater output is equal to or greater than zero. 8. The control method of the heat treatment device according to claim 6, characterized in that: The blower output calculation unit generates a blower output when the slope of the heater output from the heater output calculation unit is lower than a certain threshold, and stops the blower output when the slope of the heater output is higher than a certain threshold. 9. The control method of the heat treatment device according to claim 6, characterized in that: The method also includes the step of: converting the blower output from the blower output calculation unit into the flow rate of the cooling medium through the flow control calculation. 10. The control method of the heat treatment device according to claim 9, characterized in that: The flow rate control calculation unit controls the rotation speed of the blower according to the flow rate of the cooling medium. 11. A heat treatment device, characterized in that, possesses: Furnace body; The heater is arranged on the inner peripheral surface of the furnace body; A processing container, which is arranged in the furnace body, forms a space with the furnace body, and accommodates a plurality of objects to be processed inside the processing container; A blower, which is connected to the furnace body via a cooling medium supply line, and supplies cooling medium to the space between the furnace body and the processing container; a valve mechanism that regulates the flow of cooling medium supplied from the blower; a temperature sensor that detects the temperature inside or outside the processing vessel; and a control device that controls the heater and the valve mechanism to adjust the temperature in the processing container so that the temperature in the processing container converges to a predetermined target temperature, Wherein, the above-mentioned control device has: a heater output calculation unit, which determines the heater output when only the heater is used for temperature adjustment based on a predetermined set temperature and a temperature from a temperature sensor; and a cooling output calculation unit, based on The heater output from the heater output calculation unit determines the cooling output; and the flow control calculation unit converts the cooling output from the cooling output calculation unit into the cooling medium flow rate, wherein the flow control calculation unit controls the valve according to the cooling medium flow rate mechanism. 12. The heat treatment apparatus according to claim 11, wherein: The cooling output computing unit generates a cooling output when the heater output from the heater output computing unit is negative, and stops the cooling output when the heater output is equal to or greater than zero. 13. The heat treatment apparatus according to claim 11, wherein: The cooling output calculation unit generates a cooling output when the slope of the heater output from the heater output calculation unit is lower than a certain threshold, and stops the cooling output when the slope of the heater output is higher than a certain threshold. 14. A method for controlling a heat treatment device, used for controlling the heat treatment device according to claim 11, the method is characterized in that it has the following steps: In the heater output calculation unit of the control device, the heater output when the temperature is adjusted by only the heater is determined based on the predetermined set temperature and the temperature from the temperature sensor; The cooling output is determined by the cooling output calculation unit based on the heater output from the heater output calculation unit; and The cooling output from the cooling output calculation unit is converted into the cooling medium flow rate by the flow control calculation unit, Wherein, the flow rate control computing unit controls the valve mechanism according to the coolant flow rate. 15. The control method of the heat treatment device according to claim 14, characterized in that: The cooling output computing unit generates a cooling output when the heater output from the heater output computing unit is negative, and stops the cooling output when the heater output is equal to or greater than zero. 16. The control method of the heat treatment device according to claim 14, characterized in that: The cooling output calculation unit generates a cooling output when the slope of the heater output from the heater output calculation unit is lower than a certain threshold, and stops the cooling output when the slope of the heater output is higher than a certain threshold.

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