TW201723716A - Heater control device, heater control method, substrate processing device, and substrate processing method - Google Patents

Abstract

The present invention is to control the heater to make the temperature of the quartz plate the target temperature value in accordance with the heater for heating the quartz plate, the thermocouple for detecting the temperature of the quartz plate, and the temperature information value output from the thermocouple. The thermocouple is provided on the quartz plate, and the heater control unit has a pre-processing unit that inputs temperature information values from the four thermocouples, and the minimum value of the used temperature information value group has been removed. The remaining temperature information value of the value of the temperature information value is used to obtain a representative temperature value; and the feedback control unit controls the heater so that the representative temperature value becomes the target temperature value.

Description

Heater control device, heater control method, substrate processing device, and substrate processing method

The present invention relates to a heater control device, a heater control method, a substrate processing device, and a substrate processing method.

Various substrate processing apparatuses are known, and a semiconductor substrate is heated by a high temperature plate or a furnace, and a solvent or a chemical liquid is added to process a semiconductor substrate (etching process, etc.) (for example, Japanese Laid-Open Patent Publication No. Hei 9-134872) .

In such a substrate processing apparatus, a heater control for heating an object such as a high temperature plate or a furnace is generally a PID control (Proportional-Integral-Differential Controller). Fig. 7 shows an example in which a heater is used to heat a high temperature plate, and heat of the heater 101 is transmitted through the heat transfer body 101a to heat the high temperature plate 102. In the high temperature plate 102, a temperature detector 103 is provided in order to detect the temperature value Tp. The temperature value Tp detected by the temperature detector 103 is input to the comparator 104a of the feedback control unit 104, and the difference ΔT between the target temperature value Tx of the high temperature plate 102 input from the outside is calculated. Then, the PID control unit 104b of the feedback control unit 104 performs calculation of PID control (proportional, integral, and derivative) for the difference ΔT, and outputs the result from the AMP (amplifier) 105 to the heater 101 based on the calculation result. The power is adjusted. Thereby, the heater 101 is controlled to maintain the high temperature plate 102 at the target temperature value Tx.

In the above control method of the heater, there are the following problems. In other words, when the object such as the high temperature plate or the furnace is set to the target temperature value by controlling the heater, it is possible to appropriately perform the disturbance (natural heat release or the like) applied to the object. Control, but in the case where the interference is local, it is difficult to perform appropriate control. For example, a liquid droplet such as a chemical liquid may locally adhere to a high temperature plate. At this time, if the droplet attached to the high temperature plate is far from the place where the temperature detector is disposed, the temperature detector can be outputted with an appropriate temperature value without being affected by the liquid droplet. Therefore, proper control of the heater can be performed based on the output of the temperature detector. However, if the droplet accidentally adheres to a place where the temperature detector is disposed, the temperature detector detects a large temperature drop or a temperature rise. At this time, even if the actual temperature value of the high temperature plate is not much worse than the target temperature value, the PID control based on the temperature value detected by the temperature detector is excessively reacted to make the detection. The temperature value returned returns to the target temperature value. As a result, proper control of the heater may not be possible due to overshoot or the like. Factors such as droplets that locally change the temperature value will be sporadic if they are attached to the vicinity of the temperature detector, so that no precise action can be taken.

In the case as described above, the temperature detector is not abnormal. The temperature detector correctly measures the temperature at which it is placed. The point is: when the attachment of the droplet is not constant for the object such as the high temperature plate to be temperature controlled (that is, the interference is local), for this reason, the temperature value detected by the temperature detector will Great changes. Therefore, even if the heater is controlled, the object cannot be set to the target temperature value.

An object of the present invention is to provide a heater control device, a heater control method, a substrate processing device, and a substrate processing method, which can perform appropriate heater control even when local disturbance occurs.

A heater control device according to an embodiment of the present invention is a heater control device that heats a heater, a temperature detector that detects a temperature of the object to be heated, and a temperature information value that is output from the temperature detector. The heater is controlled such that the temperature of the object to be heated is a target temperature value, and the temperature detector is provided in the plurality of heaters, and has a preprocessing unit, and the plurality of temperature detectors Enter a temperature information value, and use the remaining temperature information value of at least one temperature information value from one or both of the minimum value or the maximum value among the input temperature information value groups to obtain a representative temperature value. And a feedback control unit that controls the heater such that the representative temperature value becomes the target temperature value.

A heater control method according to an embodiment of the present invention is a heater control method for controlling a heater to set a temperature of the object to be heated to a target temperature value based on a temperature information value output from a temperature detector that detects a temperature of the object to be heated. Further, a plurality of temperature detectors are provided in the object to be heated, and at least one of the minimum or maximum values is removed from among the temperature information value groups detected by the plurality of temperature detectors. The remaining temperature information value of the temperature information value is obtained as a representative temperature value, and the heater is controlled such that the representative temperature value becomes the target temperature value.

A substrate processing apparatus according to an embodiment of the present invention includes: a substrate holding portion; a plate as a heating target disposed opposite to the substrate above a substrate held by the substrate holding portion; and a heater for heating the plate; a plurality of temperature detectors of the board; and the aforementioned heater control unit.

The substrate processing method according to the embodiment of the present invention includes a plate as a heated body disposed above the substrate above the substrate held by the substrate holding portion, a heater for heating the plate, and a plurality of temperatures provided on the plate The detector is controlled by the aforementioned heater control method.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a plan view schematically showing a heater control unit 100 according to a first embodiment of the present invention, and FIG. 2 is a schematic view of a substrate processing apparatus 10 according to a first embodiment of the present invention. A cross-sectional view of the processing unit 20 is displayed. In the substrate processing apparatus 10 of the present embodiment, a semiconductor substrate such as a phosphoric acid aqueous solution heated by a heater or pure water (hereinafter collectively referred to as a processing liquid S) is used as an example. W surface treatment device.

The substrate processing apparatus 10 includes a processing unit 20 and a heater control unit 100. The heater control unit 100 constitutes a heater control device, and the details thereof will be described later, and the heater 80 incorporated in the processing unit 20 can be controlled.

The processing unit 20 includes a substrate holding unit 30 and a rotating table 40 that can rotate the substrate holding unit 30 around the axis C in the vertical direction. The quartz plate 50 is disposed above the substrate holding unit 30 and is formed as a heated body. a bottomed cylindrical shape; four thermocouples (temperature detectors) 60 disposed at the bottom of the quartz plate 50; heat transfer sheets 70 disposed on the respective thermocouples 60; and a heat transfer sheet 70 disposed above the heat transfer sheets 70 Heater 80. In addition, in FIG. 2, the thermocouple 60 is shown by a solid line. The opposing surface of the quartz plate 50 and the semiconductor substrate W is a horizontal plane. Further, when the semiconductor substrate W to be processed has a circular shape, the surface of the quartz plate 50 opposed to the semiconductor substrate W is also circular, and the radius thereof is the same as or larger than the radius of the semiconductor substrate W. As shown in FIG. 1, the four thermocouples 60 are disposed, for example, at intervals of 90 degrees on the same circumference centering on the rotation center C of the rotary table 40. From each of the thermocouples 60, for example, a voltage value (hereinafter also referred to as "temperature information value") corresponding to the temperature value (°C) of the installation portion is input to the heater control unit 100 before the processing unit 110 (pre-processing) unit). Further, the previous processing unit 110 has a function of converting the temperature information value input from the thermocouple 60 into a temperature value (°C). This conversion is performed using a well-known technique using a numerical formula, a conversion table, or the like. Further, in the present specification, the temperature value obtained as described above is also referred to as a temperature value corresponding to the temperature information value. The heat transfer sheet 70 may be, for example, a sheet of a material having a high thermal conductivity like graphite. Further, instead of a sheet, a metal plate made of a metal material having a high thermal conductivity may be used. The quartz plate 50, the thermocouple 60, the heat transfer sheet 70, and the heater 80 constitute a heating portion 85.

In the present embodiment, the "surface" of the quartz plate 50 refers to a surface ("lower" in FIG. 1) facing the semiconductor substrate W, and the "bottom" and "bottom surface" of the quartz plate 50. That is, the surface facing the surface of the quartz plate 50 ("top" in Fig. 1).

The treatment unit 20 includes a cup 21 that receives the treatment liquid S, a discharge port 22 that is provided at the bottom of the cup 21 to discharge the treatment liquid S, and a discharge valve 23 that is provided below the discharge port.

In Fig. 2, reference numeral 90 denotes a chemical supply unit for supplying a chemical solution, 91 is an opening and closing valve, 92 is a supply pipe, 95 is a pure water supply unit for supplying pure water, and 96 is an open/close valve. Further, 41 denotes a rotation mechanism of the rotary table 40, and 99 denotes an elevation mechanism for moving the quartz plate 50 up and down.

In FIG. 2, the control unit 200 is a control unit that controls the substrate processing apparatus 10. The control unit 200 controls the operation of the elements provided in the processing unit 20. Specifically, the operations of the chemical solution supply unit 90, the pure water supply unit 95, the rotation mechanism 41, the elevation mechanism 99, the heater control unit 100, the opening and closing valves 91, 96, and the like are controlled. Further, the control unit 200 may also serve as the heater control unit 100.

Referring back to FIG. 1 , the heater control unit 100 includes a pre-processing unit 110 , a feedback control unit 120 (feedback control unit), and a thyristor unit (power conditioner) 130 .

The pre-processing unit 110 obtains the representative temperature value T based on the plurality of temperature information values T1 to T4 from the thermocouples 60. For example, the four temperature information values T1 to T4 are arranged in ascending order, and the center of the three temperature information values of the lowest temperature information value (that is, the temperature information value corresponding to the lowest temperature value when the temperature value is converted) is removed. The value (in this case, the second value from the top) is converted into a temperature value, and the converted value is determined as the representative temperature value T.

The feedback control unit 120 performs temperature control of the heater 80 based on the difference ΔT between the representative temperature value T obtained by the pre-processing unit 110 and the target temperature value Tx (for example, 200 ° C) input from the outside with respect to the quartz plate 50.

The thyristor unit 130 adjusts the supply power to the heater 80 in accordance with the output from the feedback control unit 120.

The heater control unit 100 configured as described above controls the temperature of the heater 80 as follows.

First, the target temperature value Tx of the quartz plate 50 is input to the heater control unit 100 from the outside. At the feedback control unit 120, PID control is performed to control the amount of electric power of the thyristor unit 130 to heat the heater 80. By the temperature rise of the heater 80, heat is transmitted through the heat transfer sheet 70 and transmitted to the quartz plate 50, and the temperature value of the quartz plate 50 gradually rises. At this time, the temperature information values T1 to T4 are input from the four thermocouples 60 to the pre-processing unit 110. In the pre-processing unit 110, the four temperature information values T1 to T4 are arranged in ascending order, and the central value of the three temperature information values from which the lowest temperature information value has been removed (in this case, the second value from the upper number) The temperature value is converted into a representative temperature value T. This representative temperature value T is input to the feedback control unit 120. In the feedback control unit 120, the representative temperature value T input from the previous processing unit 110 is compared with the target temperature value Tx, and feedback control of the heater 80 is performed to make the temperature value of the quartz plate 50 (correctly, use The representative temperature value T) determined from the temperature information value of each thermocouple 60 becomes the target temperature value Tx. Further, the pre-processing unit 110 periodically extracts the temperature information values sequentially input from the respective thermocouples 60, and each time the extraction is performed, the above-mentioned representative temperature value T is obtained and updated. Further, the heater control unit 100 performs temperature control of the heater 80 based on the updated representative temperature value T.

Next, the overall operation of the substrate processing (chemical liquid processing) using the substrate processing apparatus 10 will be described. The operation control described above is performed by the control unit 200. Further, the chemical solution may be, for example, an aqueous phosphoric acid solution, sulfuric acid or a mixture thereof.

First, in the processing unit 20, the semiconductor substrate W is placed on the substrate holding portion 30 and sandwiched. Next, the turntable 40 is driven to rotate the semiconductor substrate W.

Then, the quartz plate 50 is lowered by the elevating mechanism 99, so that the surface of the quartz plate 50 (the surface facing the semiconductor substrate W) is close to the upper surface of the semiconductor substrate W, so that a small gap is formed therebetween. At the position (down position), the opening and closing valve 91 is opened, and the chemical liquid (treatment liquid S) heated to about 160 ° C, for example, is supplied from the chemical supply unit 90 to the semiconductor substrate W through the supply pipe 92 (state of FIG. 3). ). The chemical liquid enters between the upper surface of the semiconductor substrate W and the surface of the quartz plate 50, and in a state where the liquid film of the chemical liquid is held on the upper surface of the semiconductor substrate W, the semiconductor substrate is subjected to a chemical reaction of the chemical liquid for a predetermined time. Chemical treatment such as etching or film peeling on W. In this process, the chemical liquid on the semiconductor substrate W is heated by the quartz plate 50. In addition, the above-mentioned "small gap" refers to a state in which at least a part of the liquid film of the chemical solution (treatment liquid S) held on the upper surface of the semiconductor substrate W and the quartz plate 50 are provided. The interval of surface contact.

In the treatment such as etching or film peeling, the gap between the surface of the quartz plate 50 and the upper surface of the semiconductor substrate W is maintained in a small state, and the chemical liquid is continuously supplied to the gap. After the completion of the chemical treatment, the opening and closing valve 91 is closed to stop the supply of the chemical solution. Then, the opening and closing valve 96 is opened, pure water is supplied from the pure water supply unit 95, and the surface of the quartz plate 50 and the upper surface of the semiconductor substrate W are washed. At this time, the gap between the surface of the quartz plate 50 and the upper surface of the semiconductor substrate W is also maintained in a small state, and the liquid film of the pure water (treatment liquid S) is held on the upper surface of the semiconductor substrate W for a predetermined time. The surface of the quartz plate 50 is cleaned and the upper surface of the semiconductor substrate W is cleaned. When the cleaning process is completed, the quartz plate 50 is raised by the elevating mechanism 99 to a position far from the upper surface of the semiconductor substrate W, and is placed at a predetermined standby position. At this time, a large gap is formed between the surface of the quartz plate 50 and the upper surface of the semiconductor substrate W. Then, the on-off valve 96 is closed to stop the supply of pure water. In addition, the above-mentioned "larger gap" refers to a state in which the interval between the quartz plate 50 and the liquid film of the pure water (treatment liquid S) held on the upper surface of the semiconductor substrate W is separated. interval.

After the cleaning treatment with pure water, the rotary table 40 is rotated at a high speed if necessary, and the treatment liquid S remaining on the semiconductor substrate W is removed. Then, the semiconductor substrate W is carried out from the substrate holding portion 30. Thereafter, the next semiconductor substrate W is carried into the substrate holding portion 30, and the processing is repeated.

Next, the control of the heater 80 by the heater control unit 100 when the quartz plates 50 are positioned at the lowered position and the standby position, respectively, will be described.

First, when the quartz plate 50 is positioned at the lowered position, a small gap is formed between the surface of the quartz plate 50 and the semiconductor substrate W. The treatment liquid S is supplied to the gap, and is subjected to etching, film peeling, or washing. At this time, the surface of the quartz plate 50 is maintained in a state in which at least a part of the processing liquid S held on the upper surface of the semiconductor substrate W is in contact with the processing liquid S, and the attached processing liquid S is not seen. Wherever it comes into contact with air, it will vary completely randomly on the surface of the quartz plate 50.

Therefore, if the treatment liquid S is a chemical liquid, as described earlier, the temperature value of the chemical liquid (for example, 160 ° C) is lower than the temperature value of the quartz plate 50 (for example, 200 ° C), but in the condition as described above. Since the chemical liquid randomly contacts the surface of the quartz plate 50 at all, the entire quartz plate 50 is cooled substantially uniformly. Therefore, the temperature values obtained from the temperature information values of the four thermocouples 60 (as described above, for example, the temperature values obtained by converting the temperature information values) are substantially uniformly reduced.

As described above, in the pre-processing unit 110, the lowest temperature information value is removed from among the four temperature information values that display substantially the same value, and the central value of the upper three temperature information values, that is, The temperature value obtained from the second value is used as the representative temperature value T. At this time, since the possibility that the abnormal value is included among the temperature information values output from the four thermocouples 60 is low, the representative temperature value T obtained by the pre-processing unit 110 is appropriately displayed. The temperature value of the plate 50. Then, the heater control unit 100 appropriately performs feedback control of the heater 80 so that the representative temperature value T becomes the target temperature value Tx of the quartz plate 50.

After the etching or the film peeling treatment, as described above, the semiconductor substrate W and the quartz plate 50 are washed using pure water. At this time, the supply temperature of the pure water is lower than the supply temperature (about 160 ° C) of the previous chemical solution (about 20 ° C), and the feedback control of the heater 80 is performed in the same manner as in the case of performing the chemical liquid treatment. Further, when the gap between the quartz plate 50 and the semiconductor substrate W is small, the temperature value is substantially uniformly lowered on the surface of the quartz plate 50 for the same reason as the above-described supply of the chemical liquid. Therefore, the feedback control of the heater 80 can be appropriately performed as in the case of the chemical liquid treatment.

In addition, as described above, if the probability that the four temperature information values have almost no difference when the quartz plate 50 is at the lowered position is considered to be high, the lowest value may not be removed only when the quartz plate 50 is at the lowered position. The temperature information value is used, and all temperature information values are used to find the representative temperature value T.

Next, the case where the quartz plate 50 is positioned at the standby position will be described. At this time, a large gap is formed between the surface of the quartz plate 50 and the upper surface of the semiconductor substrate W. (State of Figure 4).

In the present embodiment, when the quartz plate 50 is positioned at the standby position, it is also possible to control that the representative temperature value T obtained from the temperature information value from the thermocouple 60 can be maintained at the target temperature value Tx. This is for preparation at the start of the processing of the next semiconductor substrate W. Further, as described above, when the quartz plate 50 subjected to pure water is cleaned, the heater control unit 100 may perform feedback control of the heater 80. However, for the sake of explanation, it is assumed that: When the cleaning time of the quartz plate 50 of pure water is used, the representative temperature value T is only 150 degrees (target temperature value Tx200 ° C or less).

When the quartz plate 50 is raised and positioned at the standby position, on the surface of the quartz plate 50, sometimes the pure water at the time of washing is adhered in the form of the droplet Se but not entirely. The remaining droplet Se will slowly evaporate on the surface of the quartz plate 50. During the evaporation of the droplet Se, heat is taken away from the quartz plate 50. Therefore, when the droplet Se is accidentally left on the surface of the quartz plate 50 at a position opposed to the arrangement of the thermocouple 60 or at a position opposed to the vicinity of the arrangement, the thermocouple is derived from the thermocouple. The temperature information value of 60 is much lower than the temperature information value of the thermocouple 60 from the opposite side without the droplet Se. Although it may vary depending on the target temperature value Tx or the heat capacity of the quartz plate 50, there is a possibility that a difference of 50 ° C or more may occur.

Up to now, there is one thermocouple for temperature control and feedback. Therefore, when the droplet occasionally remains on the surface of the quartz plate at a position opposite to where the thermocouple is disposed, the heater control portion may generate temperature information from the thermocouple according to an abnormal value. The value is used to control the heater, so there is an excessive overheating of the heater to cause overshoot. Overshoot can sometimes cause the heater to break. On the other hand, when the droplet attached to the position opposite to the thermocouple completely evaporates, if the quartz plate is in an overheated state, the heater control unit will not be able to control the temperature, and the temperature of the quartz plate has not dropped to When the target temperature value is reached, the next process is performed, and there is a problem that a defect occurs. The defective condition means, for example, that the temperature of the quartz plate when the next semiconductor substrate W is started to be processed is too high, and a processing rate higher than that required for processing the substrate using the processing liquid is obtained, for example, etching. In the treatment, the excessive processing such as the etching treatment of the required thickness or more is performed, or the processing at the start of the processing and the time when the predetermined time passes is changed, and the stabilization cannot be performed.

On the other hand, in the present embodiment, for example, four thermocouples 60 are provided at the bottom of the quartz plate 50. Further, a case is considered in which, on the surface of the quartz plate 50, the droplets are incidentally attached to a position opposite to the arrangement of one of the four thermocouples (the thermocouples that output the temperature information value T4). There is no droplet attached at the position opposite to the other thermocouples. At this time, the temperature information values T1 to T3 will have substantially the same value, but the temperature information value T4 from the thermocouple disposed at a position opposite to the position where the liquid droplets are attached will be the lowest. Assume (T1≧T2≧T3)>T4. The temperature information values T1 to T4 of the four thermocouples 60 are input to the pre-processing unit 110, and the lowest temperature information value T4 among the four is removed. The temperature value obtained from the central value (= T2) of the upper three temperature information values T1 to T3 is obtained as the representative temperature value T. This representative temperature value T is input to the feedback control unit 120. In the feedback control unit 120, feedback control of the heater 80 is performed so that the representative temperature value T becomes the target temperature value Tx of the quartz. In addition, the fact that the representative temperature value T is updated one by one is as described above.

According to the heater control unit 100 of the substrate processing apparatus configured as described above, even if the chemical liquid or the pure water is accidentally attached to the surface of the quartz plate 50, it is opposed to the specific thermocouple 60 disposed at the bottom of the quartz plate 50. Or near it, and locally generate a large temperature drop, the temperature information value from the thermocouple will also be removed in the stage of determining the representative temperature value T, without generating a large feedback control. influences. Therefore, the electric power of the thyristor unit 130 is not excessively increased, and overshoot can be avoided, and proper heater 80 control and temperature management of the quartz plate 50 can be realized. Moreover, when this is used for the substrate processing apparatus 10, the stabilization process of the semiconductor substrate W can be implement|achieved.

Further, in the present embodiment, the lowest temperature information value among the temperature information value groups obtained from the thermocouple is mechanically removed, and one or one of the temperature information value groups recognizes which temperature information value is abnormal. The processing is different. Therefore, even if the abnormality detecting device or the like of the temperature information value is not particularly provided, the temperature control of the heater can be performed more appropriately than in the past.

Further, in the above example, the central value of the remaining temperature information value group is removed from the output value from the plurality of thermocouples 60, that is, from the temperature information value group, and the lowest temperature information value is removed. The obtained temperature value is taken as the representative temperature value T. However, when the temperature information value group obtained from a plurality of thermocouples is removed from the lowest temperature information value and the representative temperature value T is obtained from the remaining temperature information value group, other methods such as an average value may be used instead of the center. value. Further, the number of thermocouples 60 is not limited to four. Further, for example, it is more preferable to remove the temperature information value of the lowest temperature information value and the second lowest temperature information value among the temperature information value groups, and the temperature information value to be removed is not limited to one. In addition, the highest temperature information value (that is, the temperature information value corresponding to the highest temperature value when converted into a temperature value) may be removed according to the type of processing performed by the processing unit 20, or the lowest temperature information value may be removed. With the highest temperature information value.

Further, the case where the highest temperature information value is removed is, for example, the following case. As described above, after the surface of the semiconductor substrate W is etched or the film is peeled off, the surface of the quartz plate 50 is washed with pure water. Finally, the temperature of the quartz plate 50 rises, and sometimes the substance which cannot be washed with pure water remains on the surface of the quartz plate 50. In view of such a situation, as shown in FIG. 5, a new chemical liquid K (maintained at a temperature higher than the target temperature value Tx of the quartz plate 50) may be sprayed for the purpose of washing the surface of the quartz plate 50. The chemical liquid nozzle 97 of the chemical liquid: for example, high-concentration phosphoric acid or high-concentration sulfuric acid is disposed around the rotary table 40, and sprays the chemical liquid K onto the surface of the quartz plate 50 positioned at the standby position.

At this time, the chemical solution K maintained at a temperature higher than the target temperature value Tx of the quartz plate 50 is intermittently ejected from the chemical solution nozzle 97 to the surface of the quartz plate 50, and further washed. In the case where the surface of the quartz plate 50 after the completion of the washing, the droplet of the high-temperature chemical liquid K accidentally adheres to one of the four thermocouples (the thermocouple that outputs T4). The position of the arrangement is opposite, and the droplet K is not attached at a position opposite to the position where the other thermocouples are disposed. At this time, the temperature information values T1 to T3 will have substantially the same value, but the temperature information value T4 from the thermocouple 60 disposed opposite to the position where the droplet K is attached will be the highest. Assume T4>(T1≧T2≧T3).

In this case, in the present embodiment, the temperature information values from the four thermocouples 60 are arranged in ascending order, and for example, the central value of the three temperature information values from which the highest temperature information value has been removed is obtained, and converted into The representative temperature value T is obtained from the temperature value, whereby appropriate heater 80 control can be performed.

Further, for example, when the use method of washing with normal temperature pure water and washing using the high-temperature chemical liquid S is used in combination, the representative temperature value T is calculated by removing the highest temperature information value and the lowest temperature information value. Appropriate control is possible.

Taking into account these matters, here, the total number of thermocouples is M, and the temperature information value removed by the reason that the detected temperature information value is low is N (N≧0), to detect the temperature. The temperature information value removed for the reason that the information value is higher is P (P≧0), and only N+P≧1, M-(N+P)≧1 is used to find the temperature information value representing the temperature value T. The number Q, Q = M - (N + P). In other words, among the temperature information value groups obtained from the plurality of thermocouples, at least one temperature information value is removed from one or both of the minimum value or the maximum value, and the representative temperature value is obtained from the remaining temperature information values. . Further, the representative temperature value T is obtained by using the number Q, and the following method can be applied in addition to the above-described central value.

For example, the value of the value, that is, the peak value in the frequency distribution of the temperature information values of the complex number (Q) can also be used as the representative temperature value T. Further, the average value of the plurality of (Q) temperature information values may be used as the representative temperature value T.

In addition, "N" and "P" are not limited to the detected temperature, and may be a predetermined number. The setting of the number can be set, for example, based on the probability that the droplets that are obtained in advance by the experiment or simulation adhere to the thermocouple.

FIG. 6 is an explanatory view schematically showing the heater control unit 100A, in particular, the substrate processing apparatus 10A according to the second embodiment of the present invention. It is noted that the same reference numerals are given to the same portions as those of FIG. 1 in FIG. 6, and detailed description thereof will be omitted. The substrate processing apparatus 10A incorporating the heater control unit 100A is an apparatus for performing surface treatment of the semiconductor substrate W by using a chemical liquid such as a heated phosphoric acid aqueous solution or pure water (treatment liquid S).

The substrate processing apparatus 10A includes a processing unit 20A and a heater control unit 100A (heater control unit). The heater control unit 100A constitutes a heater control device, which will be described later in detail, and controls the heater 80A incorporated in the processing unit 20A. The processing unit 20A is provided with a heater 80A and a thermocouple 60A (temperature detector) instead of the heater 80 and the thermocouple 60 included in the processing unit 20 described above. The quartz plate 50 is divided into a plurality of concentric circular regions centered on the rotation center of the rotary table 40, and heaters 80A (81, 82, 83) are individually provided in the respective regions. Further, in each of the regions, the thermocouples 60A (61, 62, 63) are provided at three intervals of 120 degrees in Fig. 6 .

The heater control unit 100A includes pre-processing units 111, 112, and 113, feedback control units 121, 122, and 123, and sluice fluid units (power conditioners) 131, 132, and 133 provided corresponding to respective regions of the quartz plate 50. .

The pre-processing units 111, 112, and 113 correspond to the pre-processing unit 110, and determine the representative temperature values Tx1, Tx2, and Tx3 with respect to the area based on the plurality of temperature information values from the thermocouples 60A of the respective corresponding regions. . For example, the pre-processing unit 111 sorts the temperature information values t11 to t13 output from the three thermocouples 61 in ascending order, and removes the central value of the two temperature information values from which the lowest temperature information value is removed (the median value of the two data values) The two average values are converted into temperature values, and the converted values are obtained as representative temperature values Tx1. Similarly, the pre-processing unit 112 obtains the representative temperature Tx2 using the temperature information values t21 to t23 output from the three thermocouples 62. Similarly, the pre-processing unit 113 obtains the representative temperature Tx3 using the temperature information values t31 to t33 output from the three thermocouples 63.

The feedback control units 121, 122, and 123 correspond to the aforementioned feedback control unit 120, and based on the representative temperature values Tx1, Tx2, and Tx3 respectively obtained by the previous processing units 111, 112, and 113, and the target temperature values input from the outside. The differences ΔTa, ΔTb, and ΔTc between Txa, Txb, and Txc are feedback control of the heaters 81, 82, and 83.

The thyristor units 131, 132, and 133 correspond to the aforementioned thyristor unit 130, and adjust the supply power to the corresponding heaters 81, 82, and 83 based on the outputs from the respective feedback control units 121, 122, and 123. .

In the substrate processing apparatus 10A configured as above, the temperatures of the heaters 81, 82, and 83 are controlled as follows. In addition, the control of the entire substrate processing apparatus 10A is controlled by a control unit (not shown). Further, the control unit may be the heater control unit 100A as in the first embodiment.

First, the target temperature values Txa, Txb, and Txc of the quartz plate 50 are input to the heater control unit 100A from the outside. The feedback control units 121 to 123 perform PID control, control the amount of electric power of the sluice fluid units 131 to 133, and heat the heaters 81 to 83. By the temperature rise of the heaters 81 to 83, heat is transmitted through the heat transfer sheet 70 and transmitted to the quartz plate 50, and the temperature value of the quartz plate 50 gradually rises. At this time, the temperature information value is input from the three thermocouples 61 to the pre-processing unit 111. Next, in the pre-processing unit 111, the lowest temperature information value among the three temperature information values is removed, and for example, the central value is obtained from the remaining two temperature information values (the central value of the two data is an average of two) The converted temperature value is converted into a representative temperature value Tx1. The obtained representative temperature value Tx1 is input to the feedback control unit 121. The feedback control unit 121 compares the representative temperature value Tx1 input from the previous processing unit 111 with the target temperature value Txa, and performs feedback control of the heater 81 based on the difference ΔTa. Similarly, the feedback control of the heaters 82 and 83 is performed based on the difference ΔTb between the representative temperature value Tx2 and the target temperature value Txb, and the difference ΔTc between the representative temperature value Tx3 and the target temperature value Txc.

The processing of the semiconductor substrate W is processed in the same manner as described above. Further, the details of the temperature detection and the temperature control are performed in the same manner as the above-described heater control unit 100 for each region. Therefore, on the surface of the quartz plate 50, even when the chemical liquid or the pure water is accidentally attached to a position opposite to the position where a part of the thermocouples 61 to 63 is disposed, or in the vicinity thereof, since the liquid can be excluded Since the influence of the temperature information values of the thermocouples 61 to 63 having a large temperature drop occurs, the control of the appropriate heater 80A and the temperature management of the quartz plate 50 can be realized. In particular, it is also possible to manage the temperature distribution in the area of response. Further, if this is used in the substrate processing apparatus 10A, the processing for the stabilization of the semiconductor substrate W can be realized.

Further, the present invention is not limited to the above embodiment. The number of heaters or the number of temperature detectors is not limited to the above examples. Further, the logic for representing the temperature value may be obtained, and the representative temperature value may be determined according to other principles, for example, weighting.

Further, in the above embodiment, the thermocouple is provided on the bottom surface of the quartz plate, that is, the opposing surface of the surface to which the treatment liquid S comes into contact. However, it is also possible to provide a thermocouple on the surface side of the quartz plate. At this time, it should be disposed in the protective cover so that the thermocouple is not damaged by the treatment liquid.

Further, the pre-processing unit outputs the temperature information value converted into the temperature value (° C.) as a representative temperature value to the feedback control unit, but since the output data is output based on the unit of information controlled by the heater control unit, It must be converted to a temperature value for output, for example, it can be maintained as a voltage value.

Further, when the temperature value is determined from the temperature information value, the step of arranging the temperature information values in ascending order and removing the lowest temperature information value is described, but they may be arranged in descending order. Of course, it can also be implemented without rearranging the order.

Further, an example has been described in which only the lowest temperature information value or the highest temperature information value is removed, but two or more may be removed. The number of such removals is determined in consideration of the total number of temperature detectors or the degree of occurrence of sporadic interference. In this regard, as mentioned earlier.

Further, although a thermocouple is taken as an example of a temperature detector, for example, a resistor, a thermal resistor, or the like may be used as long as it can detect the temperature.

Further, an example in which a plurality of temperature detectors are provided for one heater has been described, but a plurality of heaters may be controlled using representative temperature values obtained from temperature information values from a plurality of temperature detectors.

Further, the substrate processed by the substrate processing apparatus is exemplified as the semiconductor substrate W. However, the present invention is not limited thereto, and may be applied to a liquid crystal substrate or a glass substrate such as a photomask.

Further, as the body to be heated is not limited to the quartz plate 50 and the like, various modifications can be made without departing from the gist of the invention. [Industrial Applicability]

A heater control device, a heater control method, a substrate processing device, and a substrate processing method capable of performing appropriate heater control even when interference is locally generated can be obtained.

10, 10A‧‧‧ substrate processing device
20, 20A‧‧ ‧ Processing Department
21‧‧‧ cup body
22‧‧‧Export
23‧‧‧ discharge valve
30‧‧‧Substrate retention department
40‧‧‧Rotating table
41‧‧‧Rotating mechanism of the rotary table 40
50‧‧‧Quartz plate
60, 60A (61, 62, 63) ‧ ‧ thermocouple (temperature detector)
70‧‧‧ Heat Transfer Sheet
80, 80A (81, 82, 83) ‧ ‧ heater
85‧‧‧ heating department
90‧‧‧Drug supply department
91, 96‧‧‧Opening and closing valve
92‧‧‧Supply tube
95‧‧‧Pure Water Supply Department
97‧‧‧Drug nozzle
99‧‧‧ Lifting mechanism
100, 100A‧‧‧Heater Control Department
101‧‧‧heater
101a‧‧‧ heat transfer body
102‧‧‧High temperature plate
103‧‧‧ Temperature detector
104‧‧‧Feedback Control Department
104a‧‧‧ comparator
104b‧‧‧PID Control Department
105‧‧‧AMP(amplifier)
110, 111, 112, 113‧‧‧ pre-processing units
120, 121, 122, 123‧‧‧ feedback control unit (feedback control unit)
130, 131, 132, 133‧‧ ‧ brake fluid unit (power regulator)
200‧‧‧Control Department
C‧‧‧Axis in the vertical direction
K‧‧‧ liquid
S‧‧‧ treatment solution
Se‧‧‧ droplet
T‧‧‧ represents the temperature value
T1～T4‧‧‧ Temperature information value
Tp‧‧‧ temperature value
Tx, Txa, Txb, Txc‧‧‧ target temperature values
Tx1, Tx2, Tx3‧‧‧ represent temperature values
W‧‧‧Semiconductor substrate

[Fig. 1] Fig. 1 is an explanatory view schematically showing a heater control unit, in particular, a substrate processing apparatus according to a first embodiment of the present invention. [Fig. 2] Fig. 2 is a cross-sectional view schematically showing a processing unit, particularly showing a substrate processing apparatus according to a first embodiment of the present invention. Fig. 3 is a cross-sectional view schematically showing a processing procedure in the processing unit shown in Fig. 2. Fig. 4 is a cross-sectional view schematically showing a processing procedure in the processing unit shown in Fig. 2. Fig. 5 is a cross-sectional view schematically showing a processing procedure in the processing unit shown in Fig. 2. Fig. 6 is a view showing a substrate processing apparatus according to a second embodiment of the present invention, in particular, schematically showing a heater control unit. Fig. 7 is an explanatory view schematically showing an example of a substrate processing apparatus incorporating a heater control unit.

10‧‧‧Substrate processing unit

50‧‧‧Quartz plate

60‧‧‧ thermocouple (temperature detector)

80‧‧‧heater

100‧‧‧Heater Control Department

110‧‧‧Pre-processing unit

120‧‧‧Feedback Control Unit (Feedback Control Unit)

130‧‧‧ brake fluid unit (power regulator)

T‧‧‧ represents the temperature value

T1~T4‧‧‧ temperature information value

Tx‧‧‧ target temperature value

Claims (8)

A heater control device is a heater control device that controls the heating according to a heater that heats the object to be heated, a temperature detector that detects the temperature of the object to be heated, and a temperature information value output from the temperature detector. The temperature detector is set to a target temperature value, wherein the temperature detector is provided in the plurality of heating bodies, and has a preprocessing unit that inputs temperature from the plurality of temperature detectors. The information value is used to determine the representative temperature value by using the remaining temperature information value of at least one temperature information value from one or both of the minimum value or the maximum value among the input temperature information value groups; And a feedback control unit that controls the heater such that the representative temperature value becomes the target temperature value. The temperature control device according to claim 1, wherein the object to be heated is divided into a plurality of regions, and each of the regions includes the heater and a plurality of temperature detectors, and the preprocessing portion uses each of the regions The temperature information values input by the respective temperature detectors determine the aforementioned representative temperature values according to the respective regions. The heater control device according to claim 1 or 2, wherein said preprocessing unit obtains an average value of said temperature information values as a representative temperature value. The heater control device according to claim 1 or 2, wherein said preprocessing unit obtains a median value of said temperature information value as a representative temperature value. A heater control device according to claim 1 or 2, wherein said preprocessing unit obtains a value of said temperature information value as a representative temperature value. A heater control method is a heater control method for controlling a heater to cause a temperature of the object to be heated to be a target temperature value based on a temperature information value output from a temperature detector that detects a temperature of the object to be heated, wherein : a plurality of temperature detectors are disposed on the object to be heated, and at least one temperature is removed from one or both of the minimum value or the maximum value among the temperature information value groups detected by the plurality of temperature detectors The remaining temperature information value of the information value is obtained as a representative temperature value, and the heater is controlled such that the representative temperature value becomes the target temperature value. A substrate processing apparatus comprising: a substrate holding portion; a plate as a heating target disposed opposite to the substrate above a substrate held by the substrate holding portion; and a heater for heating the plate; a plurality of temperature detectors of the board; and the heater control apparatus of claim 1 above. A substrate processing method comprising: a plate as a heating target; a heater disposed to face the substrate above the substrate held by the substrate holding portion, heating the plate, and a plurality of the plurality of plates provided on the plate The temperature detector is controlled by the heater control method of the above-mentioned claim 6.