Wafer temperature control device and wafer temperature control method

Abstract

A wafer temperature control device comprises a mounting unit in which a mounting surface capable of mounting a wafer is divided into a plurality of regions, a temperature control unit for adjusting the temperature of the plurality of regions, a temperature sensor for detecting the temperature of the plurality of regions, a temperature control unit for controlling the temperature of the plurality of regions, a disturbance detection unit for detecting the application of a disturbance to the region, and a switching unit for feeding back only the detected temperature of the temperature sensor installed in the region where the application of the disturbance is detected to the temperature control unit. The temperature control unit adjusts the temperature of the plurality of regions based on the detected temperature fed back by the switching unit.

Description

Technology Field

[0001] The present disclosure relates to a wafer temperature control device and a wafer temperature control method.

[0002] The present application claims priority based on Japanese Patent Application No. 2023-102659 and Japanese Patent Application No. 2023-102660, filed in Japan on June 22, 2023, and incorporates the contents thereof herein. Background Technology

[0003] Patent Document 1 discloses a temperature control device for a wafer prober. This temperature control device controls the temperature of a wafer to a target temperature and also controls the temperature distribution within the surface of the wafer. The temperature control device of Patent Document 1 comprises a stage capable of mounting a wafer and divided into multiple regions when viewed from a planar perspective, a temperature control unit installed in each region of the stage capable of independently adjusting the temperature of each region, and a temperature sensor installed in each region of the stage to detect the temperature of each region. When a local thermal disturbance is applied by energizing a chip on the wafer, the temperature control device of Patent Document 1 suppresses the local thermal disturbance and adjusts it to a target temperature by means of the temperature sensor and the temperature control unit placed in the region where the local thermal disturbance is applied. Prior art literature

[0004] Japanese Patent Publication No. 2022-125685 The problem to be solved

[0005] In a temperature control device such as the above-mentioned Patent Document 1, since it takes time for the wafer to be adjusted to the target temperature after a local thermal disturbance is applied to the wafer, it is desired to adjust the wafer temperature to the target temperature more quickly.

[0006] In addition, in a temperature control device such as the above-mentioned Patent Document 1, when the location where a local thermal outflow is applied is changed, the temperature sensor is also switched, but after switching the temperature sensor, there are cases where an overshoot occurs when the detected temperature of the switched temperature sensor is adjusted to the target temperature range by PID control.

[0007] The present disclosure is made in consideration of such problems and aims to provide a wafer temperature control device and a wafer temperature control method capable of adjusting the wafer temperature to a target temperature more quickly.

[0008] Furthermore, the present disclosure aims to provide a wafer temperature control device and a wafer temperature control method capable of suppressing the occurrence of overshoot. means of solving the problem

[0009] A temperature control device for a wafer according to one aspect of the present disclosure comprises: a mounting surface capable of mounting a wafer, a mounting section in which the mounting surface is divided into a plurality of regions when viewed from a planar view, a temperature control section for independently adjusting the temperature of the plurality of regions, a plurality of temperature sensors installed in each of the plurality of regions and detecting the temperature of the region, a temperature control section for independently controlling the temperature of the plurality of regions by the temperature control section, a disturbance detection section for detecting the application of a disturbance to the region based on the detected temperature of the temperature sensor, and a switching section for feeding back only the detected temperature of the temperature sensor installed in the region where the application of a disturbance is detected by the disturbance detection section to the temperature control section when the application of a disturbance is detected by the disturbance detection section, and the temperature control section adjusts the temperature of the plurality of regions based on the detected temperature fed back by the switching section.

[0010] A temperature control method for a wafer according to one aspect of the present disclosure includes a disturbance detection process for detecting the application of a disturbance to a wafer in which a plurality of regions are set when viewed in a planar view, and a disturbance suppression operation process for independently feedback-controlling the temperature of all regions based on the detected temperature of one region in which the disturbance application is detected when the application of a disturbance is detected.

[0011] A temperature control device for a wafer according to one aspect of the present disclosure comprises a mounting unit having a mounting surface on which a wafer is mounted, a temperature control unit capable of heating and cooling the mounting unit, a plurality of temperature sensors installed in the mounting unit, and a temperature control device for controlling the temperature control unit. The temperature control device comprises a plurality of operation amount change calculation units installed for each of the plurality of temperature sensors and calculating an operation amount change amount of the temperature control unit based on the detected temperature of the temperature sensor and a target temperature, a selection / switching unit capable of switching from a state in which an operation amount change amount calculated by one of the operation amount change calculation units is selected to a state in which an operation amount change amount calculated by another operation amount change calculation unit is selected, and an operation amount calculation unit that calculates an operation amount of the temperature control unit based on the operation amount change amount selected by the selection / switching unit.

[0012] A method for controlling the temperature of a wafer according to one aspect of the present disclosure comprises: a temperature monitoring process for detecting wafer temperatures at a plurality of locations; a process for calculating a change in amount of manipulation at each location based on the wafer temperatures at each of the plurality of locations and a target temperature detected by the temperature monitoring process; a selection and switching process for switching from a state in which a change in amount of manipulation at one location is selected to a state in which a change in amount of manipulation at another location is selected among the change in amount of manipulation at each location calculated by the process for calculating a change in amount of manipulation at each location; a process for calculating a change in amount of manipulation of the wafer temperature based on the change in amount of manipulation selected by the selection and switching process; and a temperature adjustment process for adjusting the wafer temperature based on the change in amount of manipulation calculated by the process for calculating a change in amount of manipulation. Effects of the invention

[0013] According to the present disclosure, the wafer temperature can be adjusted to the target temperature more quickly after the application of a local thermal outflow is stopped. In addition, the occurrence of overshoot can be suppressed. Brief explanation of the drawing

[0014] Figure 1 is a block diagram of a temperature control device. Figure 2 is a plan view showing the arrangement of the temperature detection unit. Figure 3 is a cross-sectional view of the mounting section and the temperature control section. FIG. 4 is a functional block diagram of the temperature control unit in the first embodiment. FIG. 5 is a control block diagram when a disturbance is applied in the first embodiment. FIG. 6 is a control block diagram during normal operation in the first embodiment. FIG. 7 is a flowchart of a temperature control method in a first embodiment. FIG. 8 is a graph showing the temperature change of each region when switching from a normal operation process to a disturbance suppression operation process in the first embodiment. Figure 9 is a graph of the temperature change corresponding to Figure 8 in the comparative example. FIG. 10 is a graph showing the temperature change of each region when switching from the disturbance suppression operation process to the normal operation process in the first embodiment. Figure 11 is a graph of the temperature change corresponding to Figure 10 in the comparative example. FIG. 12 is a control block diagram of a control device in a second embodiment. FIG. 13 is a control block diagram of the calculation unit for the change in manipulated amount in the second embodiment. FIG. 14 is a control block diagram of the operation amount calculation unit in the second embodiment. FIG. 15 is a flowchart of a temperature control method of a second embodiment. FIG. 16 is a graph showing the temperature change and operation amount of the main temperature sensor and the auxiliary temperature sensor in the second embodiment. Figure 17 is a control block diagram of the control device in the comparative example. Specific details for implementing the invention

[0015] Hereinafter, a first embodiment of the present disclosure will be described with reference to the drawings. In the first embodiment, as an example of a wafer temperature control device, a temperature control device for controlling the temperature of a wafer (the temperature of the wafer to which heat is locally input by energizing) to a target temperature on which a chip is formed and whose electrical characteristics are inspected by energizing is described as an example. For example, the wafer is formed in a disc shape.

[0016] Temperature control device

[0017] FIG. 1 is a block diagram of a temperature control device (1). FIG. 2 is a plan view showing the arrangement of a temperature detection unit (4). Also, in FIG. 2, the wafer (W) is shown as a dashed line.

[0018] As shown in FIG. 1, the temperature control device (1) comprises a mounting part (2), a temperature adjustment part (3), a temperature detection part (4) (see FIG. 3), and a control device (5). Each element of the temperature control device (1) is controlled by the control device (5).

[0019] <Mounting Section>

[0020] The mounting portion (2) has a mounting surface (10) capable of mounting a wafer (W). The mounting portion (2) is formed in a disc shape having the mounting surface (10) on the first surface (11). As shown in FIG. 2, the mounting surface (10) is formed in a circular shape when viewed from a planar view. For example, the outer diameter of the mounting surface (10) is larger than the outer diameter of the wafer (W). The mounting surface (10) is divided into a plurality of regions (21 to 24) when viewed from a planar view (for example, four in the first embodiment). These plurality of regions (21 to 24) are arranged in the periphery direction of the mounting surface (10) which forms a circle when viewed from a planar view. The regions (21 to 24) of the first embodiment form a fan shape formed by evenly dividing the mounting surface (10), which forms a circle when viewed from a planar view, in the periphery direction. Regions (21–24) are arranged in the order of regions (21–24) when viewed in a plane, in a left rotation direction (counterclockwise).

[0021] Figure 3 is a cross-sectional view of the mounting section and the temperature control section.

[0022] As shown in FIG. 3, the mounting portion (2) has a recess (13) that opens on a second surface (12) opposite to the first surface (11). The recess (13) is not open on the first surface (11) (mounting surface (10)). The recess (13) is installed in multiple areas (21 to 24) (see FIG. 2). For example, two recesses (13) are installed in each of the multiple areas (21 to 24).

[0023] Temperature Control Unit

[0024] The temperature control unit (3) can heat and cool the mounting unit (2). For example, the temperature control unit (3) independently adjusts the temperature of the mounting unit (2) for each of the multiple areas (21 to 24). For example, the temperature control unit (3) is equipped with a thermoelectric element (30), such as a Peltier element. For example, the thermoelectric element (30) is installed in each of the multiple areas (21 to 24). For example, by supplying power to the multiple thermoelectric elements (30), each area (21 to 24) can be independently heated and cooled. Each thermoelectric element (30) in each area (21 to 24) is controlled by a control device (5) (see FIG. 1). For example, a thermoelectric element (321) (see FIG. 5) is placed in region (21), a thermoelectric element (322) (see FIG. 5) is placed in region (22), a thermoelectric element (323) (see FIG. 5) is placed in region (23), and a thermoelectric element (324) (see FIG. 5) is placed in region (24).

[0025] The temperature control unit (3) is in contact with the second surface (12) of the mounting unit (2). The temperature control unit (3) has a through hole (31) connected to the concave portion (13). Multiple through holes (31) are installed corresponding to the concave portion (13). For example, multiple through holes (31) are installed two at a time in each area (21-24).

[0026] <Manipulated Quantity Calculation Unit>

[0027] The temperature control device (1) of the first embodiment is equipped with a cooling unit (35) that cools the temperature control unit (3). For example, the cooling unit (35) has a cooling channel (36) through which cooling water can flow as a water cooling plate. The cooling channel (36) is installed in each of the multiple areas (21 to 24). The cooling unit (35) is capable of independently cooling each area (21 to 24) by driving a pump, for example, not shown, to flow cooling water into each cooling channel (36). For example, the pump corresponding to the cooling channel (36) of each area (21 to 24) is controlled by a control device (5) (see FIG. 1). The cooling unit (35) has an insertion hole (37) connected to the through hole (31) of the temperature control unit (3). Multiple insertion holes (37) are installed corresponding to the through hole (31). For example, multiple insertion holes (37) are installed two at a time in each area (21-24).

[0028] Temperature detection unit

[0029] The temperature detection unit (4) detects the temperature of the regions (21 to 24) (see FIG. 2). For example, the temperature detection unit (4) is equipped with a temperature sensor (40), such as a resistance temperature detector (RTD) or a thermocouple (TC). A plurality of temperature sensors (40) are installed in each of the regions (21 to 24). For example, as shown in FIG. 2, two temperature sensors (40) are installed in each region (21 to 24). As shown in FIG. 3, the temperature sensors (40) are placed in the concave portion (13) of the mounting portion (2) through the insertion hole (37) of the cooling portion (35) and the through hole (31) of the temperature adjustment portion (3).

[0030] A plurality of temperature sensors (40) are spaced apart from each other in the periphery direction and the diameter direction of the mounting surface (10) when viewed from a planar view. A plurality of temperature sensors (40) are spaced apart from each other in each of a plurality of regions (21 to 24) when viewed from a planar view. For example, two temperature sensors (40) placed in each of the regions (21 to 24) are placed at the same position in the diameter direction and are spaced apart from each other in the periphery direction. The detected temperature of each temperature sensor (40) is input to a control device (5) (see FIG. 1).

[0031] For example, the two temperature sensors (40) placed in each area (21–24) consist of a main temperature sensor and a secondary temperature sensor. As shown in FIG. 2, for example, a main temperature sensor (41m) and a secondary temperature sensor (41s) are placed in area (21). A main temperature sensor (42m) and a secondary temperature sensor (42s) are placed in area (22). A main temperature sensor (43m) and a secondary temperature sensor (43s) are placed in area (23). A main temperature sensor (44m) and a secondary temperature sensor (44s) are placed in area (24). For example, in areas (21–24), each main temperature sensor (41m–44m) is placed at the same location. As for the placement of the main temperature sensors (41m–44m), an optimal location (for example, the center of gravity) for uniformly heating and cooling each area (21–24) can be cited. In addition, for example, each negative temperature sensor (41s to 44s) within the area (21 to 24) is positioned at the same location. As for the placement of the negative temperature sensors (41s to 44s), an example can be given to a location where the range other than the main temperature sensor (41m to 44m) within each area (21 to 24) can be appropriately observed with a given number of sensors.

[0033] Control Unit

[0034] Figure 4 is a control block diagram of a control device.

[0035] The control device (5) controls the temperature adjustment unit (3) based on the detected temperature of a plurality of temperature sensors (40). For example, the control device (5) controls the temperature adjustment unit (3) by a speed-type PID controller (Proportional Integral Derivative Controller) to set the detected temperature of the temperature sensors (40) to a target temperature (SV). As shown in FIG. 4, the control device (5) is equipped with a plurality of operation amount change amount calculation units (51), a selection / switching unit (52), and a plurality of operation amount calculation units (53).

[0036] <Calculation unit for change in manipulated variable>

[0037] Figure 5 is a control block diagram of a calculation unit for a change in manipulated amount.

[0038] A change in operation amount calculation unit (51) is installed for each of the multiple temperature sensors (40). In the first embodiment, the change in operation amount calculation unit (51) is provided with a main change in operation amount calculation unit (511m–514m) connected to the main temperature sensors (41m–44m) and a sub-change in operation amount calculation unit (511s–514s) connected to the sub-temperature sensors (41s–44s). The change in operation amount calculation unit (511m–514m) and the sub-change in operation amount calculation unit (511s–514s) receive a deviation e(k) (where “k” indicates the current sampling time) obtained by subtracting the target temperature (SV) from the respective detected temperatures of the main temperature sensors (41m–44m) and the sub-temperature sensors (41s–44s) using a subtractor (54). As shown in FIG. 5, the change amount of the manipulated amount calculation unit (51) calculates the change amount of the P term dP(k), the change amount of the I term dI(k), and the change amount of the D term dD(k) using the deviation e(k) and the deviation e(k-1) from one sampling time prior. The change amount of the manipulated amount calculation unit (51) also calculates the change amount of the P term dP(k), the change amount of the I term dI(k), and the change amount of the D term dD(k) by adding these change amounts of the P term dP(k), the change amount of the I term dI(k), and the change amount of the D term dD(k).

[0039] The selection / switching unit (52) can switch from a state in which the change in amount of manipulation calculated by one change in amount of manipulation calculation unit (51) is selected to a state in which the change in amount of manipulation calculated by another change in amount of manipulation calculation unit (51) is selected. In the selection / switching unit (52) of the first embodiment, as shown in FIG. 4, it is possible to switch between a state in which the change in amount of manipulation calculated by the change in amount of manipulation calculation unit (51) connected to the main temperature sensor is selected and a state in which the change in amount of manipulation calculated by the change in amount of manipulation calculation unit (51) connected to the secondary temperature sensor is selected.

[0040] In the first embodiment, the selection / switching unit (52) switches the selection state of two operation amount change amounts ΔMV(k), which are the calculation results of the main operation amount change amount calculation unit and the secondary operation amount change amount calculation unit corresponding to the main temperature sensor and the secondary temperature sensor installed in the same area, for example. That is, the selection / switching unit (52) of the first embodiment selects either the operation amount change amount ΔMV(k) calculated by the main operation amount change amount calculation unit and the operation amount change amount ΔMV(k) calculated by the secondary operation amount change amount calculation unit. For example, the selection / switching unit (52) of the first embodiment is configured to allow selection / switching individually for each corresponding area. For example, the selection / switching unit (52) of the first embodiment switches the selection state to use the detection result of the temperature sensor (40) closer to the location where the disturbance is applied when the location where the disturbance is applied changes within the same area.

[0041] <Manipulated Quantity Calculation Unit>

[0042] FIG. 6 is a control block diagram of a control amount calculation unit. The control amount calculation unit (53) calculates the control amount MV(k) of the temperature control unit (3) based on the control amount change amount ΔMV(k) selected by the selection / switching unit (52). The control amount calculation unit (53) is installed for each of the plurality of thermoelectric elements (30) installed in each area (21 to 24). For example, in the first embodiment, the plurality of control amount calculation units (53) includes a control amount calculation unit (531) corresponding to area (21), a control amount calculation unit (532) corresponding to area (22), a control amount calculation unit (533) corresponding to area (23), and a control amount calculation unit (534) corresponding to area (24). As shown in FIG. 4, the change in amount of control ΔMV1 is input to the control amount calculation unit (531) as the change in amount of control ΔMV(k), the change in amount of control ΔMV2 is input to the control amount calculation unit (532), the change in amount of control ΔMV3 is input to the control amount calculation unit (533), and the change in amount of control ΔMV4 is input to the control amount calculation unit (534).

[0043] As shown in FIG. 6, the control amount calculation unit (53) calculates the current control amount MV(k) by adding the control amount change amount ΔMV(k) selected by the selection / switching unit (52) to the control amount MV(k-1) from one sampling time prior. As shown in FIG. 4, the control amount calculation unit (531) outputs the control amount (MV1) as the control amount MV(k) to the thermoelectric element (321), the control amount calculation unit (532) outputs the control amount (MV2) to the thermoelectric element (322), the control amount calculation unit (533) outputs the control amount (MV3) to the thermoelectric element (323), and the control amount calculation unit (534) outputs the control amount (MV4) to the thermoelectric element (324). Additionally, the control amount calculation unit (53) may have an anti-windup circuit (not shown).

[0044] Temperature Control Method

[0045] FIG. 7 is a flowchart of a temperature control method of a first embodiment.

[0046] As shown in FIG. 7, the temperature control method of the first embodiment includes a temperature monitoring process (S01), a wafer mounting process (S02), a wafer inspection process (S03), a process for calculating a change in the amount of manipulation (S04), a selection / switching process (S05), a process for calculating a amount of manipulation (S06), and a temperature adjustment process (S07).

[0047] In the temperature monitoring process (S01), the temperature is monitored at multiple locations in at least one of the multiple regions (21 to 24). For example, in the temperature monitoring process (S01), the temperature is monitored at multiple locations in each of the multiple regions (21 to 24). For example, in the temperature monitoring process (S01), all of the multiple temperature sensors (40) installed in each of the multiple regions (21 to 24) are always monitored. After the temperature monitoring process (S01), the process proceeds to the wafer mounting process (S02).

[0048] In the wafer mounting process (S02), a wafer (W) is mounted on a mounting surface (10) having a plurality of regions (21 to 24). For example, in the wafer mounting process (S02), a disc-shaped wafer (W) is mounted so as to overlap the entire surface with respect to a circular mounting surface (10) when viewed from a flat plane. After the wafer mounting process (S02), the process proceeds to a wafer inspection process (S03).

[0049] In the wafer inspection process (S03), an inspection of the wafer (W) mounted on the mounting surface (10) is initiated. For example, local heat input is generated as a disturbance is applied by the inspection of the wafer (W). After the wafer inspection process (S03) is initiated, the process proceeds to the operation amount change amount calculation process (S04).

[0050] In the process of calculating the change in amount of manipulation (S04), the change in amount of manipulation ΔMV(k) for each location is calculated based on the detection temperature (wafer temperature) and target temperature (SV) of each location detected by the temperature monitoring process (S01). For example, in the first embodiment, the change in amount of manipulation ΔMV(k) is calculated by adding the change in amount of P, the change in amount of I, and the change in amount of D, dD(k), by the change in amount of manipulation calculation unit (51).

[0051] In the selection and switching process (S05), among the changes in the amount of operation for each location calculated by the change in the amount of operation for each location calculated by the change in the amount of operation for each location (S04), the state of selecting the change in the amount of operation for one location is switched to the state of selecting the change in the amount of operation for another location. In the first embodiment, as described above, one of the two changes in the amount of operation ΔMV(k) calculated based on the detection temperatures of the main temperature sensor and the auxiliary temperature sensor installed in the same area is selected. Additionally, if necessary, the state of selecting one of the two changes in the amount of operation ΔMV(k) is switched to the state of selecting the other. For example, in the selection and switching process (S05) of the first embodiment, the selection and switching of the change in the amount of operation ΔMV(k) is performed for each area (21 to 24).

[0052] In the operation amount calculation process (S06), the operation amount MV(k) for temperature adjustment is calculated based on the operation amount change amount ΔMV(k) selected by the selection / switching process (S05). For example, in the first embodiment, the operation amount calculation unit (53) calculates the current operation amount MV(k) by adding the operation amount change amount ΔMV(k) to the operation amount MV(k-1) from one sampling time prior.

[0053] In the temperature adjustment process (S07), the wafer temperature is adjusted based on the manipulated amount MV(k) calculated by the manipulated amount calculation process (S06). That is, the wafer (W) is heated or cooled using a thermoelectric element (30) in the area corresponding to the manipulated amount (MV) based on the calculated manipulated amount (MV).

[0054] FIG. 8 is a graph showing the temperature change and operation amount of the main temperature sensor and the negative temperature sensor in the first embodiment. In FIG. 8, the temperature change and operation amount in the first embodiment are shown as solid lines, and the temperature change and operation amount in the comparative example are shown as lines other than solid lines (dashed lines, dotted lines, dotted lines). In addition, FIG. 8 provides an example of a case where the temperature sensor (40) for feedback control of the temperature of the area (21) is switched from the main temperature sensor (41m) to the negative temperature sensor (41s). In addition, an example is provided of a case where the detected temperature of the main temperature sensor (41m) is higher than the detected temperature of the negative temperature sensor (41s).

[0055] As shown in FIG. 8, when the detected temperature of the main temperature sensor (41m) is adjusted to the target temperature (SV), the system switches from the main temperature sensor (41m) to the secondary temperature sensor (41s) (at the point of "sensor switching" in FIG. 8). By the selection / switching unit (52), the system switches from a state where the change in the amount of operation ΔMV(k) of the main operation amount change amount calculation unit (511m) is selected to a state where the change in the amount of operation ΔMV(k) of the secondary operation amount change amount calculation unit (511s) is selected. At this time, the operation amount (MV1) output from the operation amount calculation unit (531) of the first embodiment is calculated by speed-type PID control, so it gradually increases over time, and the rate of increase decreases over time until it reaches a predetermined peak value. After that, the operation amount (MV1) gradually decreases over time, and the rate of decrease also gradually decreases, and it becomes a constant operation amount (MV) that is the same as before the sensor switching point. As the thermoelectric element (321) is controlled by such an operation amount (MV1), the detected temperature of the negative temperature sensor (41s) gradually increases from the point of sensor switching and is adjusted so as not to exceed the target temperature (SV).

[0056] FIG. 9 is a control block diagram of a control device in a comparative example. In addition, parts identical to those in the first embodiment in the comparative example are described by assigning the same reference numerals.

[0057] The temperature control device in the comparative example comprises a mounting section (2) (see FIG. 3), a temperature adjustment section (3) (see FIG. 3), a temperature detection section (4) (see FIG. 3), and a control device (105) (see FIG. 9). In the temperature control device in the comparative example, similar to the first embodiment, the mounting surface (10) (see FIG. 2) is divided into four areas (21 to 24), and each area is equipped with one main temperature sensor and one secondary temperature sensor constituting the temperature detection section (4). That is, the main temperature sensor (41m) and the secondary temperature sensor (41s) are provided in area (21), the main temperature sensor (42m) and the secondary temperature sensor (42s) are provided in area (22), the main temperature sensor (43m) and the secondary temperature sensor (43s) are provided in area (23), and the main temperature sensor (44m) and the secondary temperature sensor (44s) are provided in area (24).

[0058] The control device (105) controls the temperature adjustment unit (3) (thermoelectric element (30)) based on the detected temperature of a plurality of temperature sensors (40). For example, the control device (105) controls the temperature by PID control (Proportional Integral Derivative Controller) to make the detected temperature of the temperature sensor (40) the target temperature (SV). As shown in FIG. 9, the control device (105) is equipped with a selection / switching unit (152), a subtractor (54), and an operation amount calculation unit (153 to 156). The selection / switching unit (152) is configured to switch between the main temperature sensor and the secondary temperature sensor for each region to enable the selection of one of the detected temperatures. The detected temperature selected by the selection / switching unit (152) is input to the operation amount calculation unit (153 to 156) respectively through the subtractor (54) for each region. The control amount calculation unit (153-156) calculates the control amounts (MV1-MV4) of the temperature control unit (3) by PID control based on the input from the subtractor (54).

[0059] As shown in FIG. 8, in a comparative example having the above configuration, when switching from the main temperature sensor (41m) to the negative temperature sensor (41s) by, for example, the selection / switching unit (152), a so-called switching shock occurs. Specifically, the operating amount (MV1) of the thermoelectric element (321) (indicated by a dashed line in FIG. 8) rises approximately vertically from the point of sensor switching, and when it reaches a peak value higher than the peak of the aforementioned operating amount (MV1) (for example, more than twice the value of MV1), it drops sharply and decreases from the operating amount (MV) before the point of sensor switching, and then becomes a constant operating amount (MV1) before the point of sensor switching. When the thermoelectric element (321) is controlled by the amount of manipulation (MV) of such a comparative example, the detected temperature of the negative temperature sensor (41s) (indicated by a dotted line in FIG. 8) rises rapidly from the point of sensor switching and is adjusted to the target temperature (SV) after exceeding (overshooting) the target temperature (SV).

[0060] <Effects of Action>

[0061] As described above, the wafer temperature control device (1) of the first embodiment comprises a mounting part (2) having a mounting surface (10) on which a wafer (W) is mounted, a temperature control part (3) capable of heating and cooling the mounting part (2), a plurality of temperature sensors (40) installed on the mounting part (2), and a control device (5) for controlling the temperature control part (3). The control device (5) is provided with a plurality of operation amount change amount calculation units (51) that are installed for each of the plurality of temperature sensors (40) and calculate the operation amount change amount ΔMV(k) of the temperature adjustment unit (3) based on the detected temperature and target temperature (SV) of the temperature sensor (40), a selection / switching unit (52) that can switch from a state in which the operation amount change amount ΔMV(k) calculated by one operation amount change amount calculation unit (51) is selected to a state in which the operation amount change amount ΔMV(k) calculated by another operation amount change amount calculation unit (51) is selected, and an operation amount calculation unit (53) that calculates the operation amount MV(k) of the temperature adjustment unit (3) based on the operation amount change amount ΔMV(k) selected by the selection / switching unit (52).

[0062] According to this configuration, when switching from a state in which a change in amount of control ΔMV(k) calculated by one change in amount of control calculation unit (51) is selected to a state in which a change in amount of control ΔMV(k) calculated by another change in amount of control calculation unit (51) is selected, the change in amount of control MV(k) at the time of switching can be made smaller compared to the case where the change in amount of control MV(k) is switched. By doing so, the time until the temperature of the wafer (W) is adjusted to the target temperature (SV) is not extended, and the wafer temperature can be suppressed from overshooting relative to the target temperature (SV).

[0063] In addition, in the first embodiment, the plurality of temperature sensors (40) are composed of main temperature sensors (41m to 44m) and auxiliary temperature sensors (41s to 44s), and the plurality of operation amount change amount calculation units (51) are provided with a main operation amount change amount calculation unit (511m to 514m) that calculates the operation amount change amount ΔMV(k) of the temperature adjustment unit (3) based on the detection temperature of the main temperature sensors (41m to 44m) and the target temperature (SV), and an auxiliary operation amount change amount calculation unit (511s to 514s) that calculates the operation amount change amount ΔMV(k) of the temperature adjustment unit (3) based on the detection temperature of the auxiliary temperature sensors (41s to 44s) and the target temperature (SV). The selection / switching unit (52) selects either the change in amount of operation ΔMV(k) calculated by the main change in amount of operation calculation unit (511m to 514m) or the change in amount of operation ΔMV(k) calculated by the sub-change in amount of operation calculation unit (511s to 514s).

[0064] Thus, when switching between temperature control based on the main temperature sensor and temperature control based on the negative temperature sensor, the amount of change of the control amount MV(k) can be reduced, thereby suppressing the wafer temperature from overshooting relative to the target temperature (SV).

[0065] In addition, in the first embodiment, the mounting surface (10) is divided into a plurality of regions (21 to 24) when viewed from a planar view, and the thermoelectric element (30) of the temperature control unit (3), the main temperature sensor (41m to 44m), and the secondary temperature sensor (41s to 44s) are installed in each region (21 to 24). The operation amount calculation unit (53) is installed for each of the plurality of thermoelectric elements (321 to 324) of the temperature control unit (3), the main operation amount change amount calculation unit (511m to 514m) is installed for each of the plurality of main temperature sensors (41m to 44m), and the secondary operation amount change amount calculation unit (511s to 514s) is installed for each of the plurality of secondary temperature sensors (41s to 44s). The selection / switching unit (52) selects one of the change in amount of operation ΔMV(k) calculated by the main operation amount change amount calculation unit (511m-514m) and the change in amount of operation ΔMV(k) calculated by the sub-operation amount change amount calculation unit (511s-514s) for each of the multiple areas (21-24) and outputs it to the operation amount calculation unit (531-534).

[0066] According to this configuration, since there is no need to install the same number of operation amount calculation units (531-534) as the temperature sensor (40) or the operation amount change amount calculation unit (51), the circuit configuration of the control device (5) can be simplified.

[0067] In addition, in the first embodiment, the control device (5) performs speed-type PID control by means of the operation amount change amount calculation unit (51) and the operation amount calculation unit (53).

[0068] Thus, the temperature of the wafer (W) can be rapidly adjusted to the target temperature (SV) while reducing the deviation between the temperature of the wafer (W) and the target temperature (SV).

[0069] In the wafer temperature control method of the first embodiment, the method comprises: a temperature monitoring process (S01) for detecting wafer temperatures at multiple locations; a change in operation amount calculation process (S04) for calculating a change in operation amount ΔMV(k) at each location based on the wafer temperatures at multiple locations and a target temperature (SV) detected by the temperature monitoring process (S01); a selection / switching process (S05) for switching from a state in which a change in operation amount ΔMV(k) at one location is selected among the change in operation amount ΔMV(k) at each location calculated by the change in operation amount calculation process (S04) to a state in which a change in operation amount ΔMV(k) at another location is selected; a change in operation amount calculation process (S06) for calculating a change in operation amount MV(k) for temperature adjustment based on the change in operation amount ΔMV(k) selected by the selection / switching process (S05); and the temperature of the wafer (W) based on the change in operation amount MV(k) calculated by the change in operation amount calculation process (S06). It includes a temperature adjustment process (S07) for adjustment.

[0070] According to this configuration, the amount of change in the control amount MV(k) during switching can be reduced compared to when the control amount MV(k) is switched. By doing so, the time until the wafer (W) temperature is adjusted to the target temperature (SV) is not extended, and the wafer temperature can be suppressed from overshooting relative to the target temperature (SV).

[0071] (A variation of the first embodiment)

[0072] In the first embodiment described above, the mounting surface was described as being formed in a circular shape when viewed from a planar view, but it is not limited thereto. For example, the mounting surface may be formed in a rectangular shape when viewed from a planar view. For example, the shape of the mounting surface when viewed from a planar view can be changed according to required specifications, such as the shape of the wafer (W).

[0073] In the first embodiment described above, an example was given in which a plurality of temperature sensors (40) are spaced apart from each other in the peripheral direction and the diameter direction of the mounting surface when viewed from a planar view, but this is not limited thereto. For example, the plurality of temperature sensors (40) do not need to be spaced apart from each other in the peripheral direction and the diameter direction of the mounting surface when viewed from a planar view. For example, the arrangement of the plurality of temperature sensors (40) can be changed according to the required specifications.

[0074] In the first embodiment described above, an example was given in which a plurality of regions (21 to 24) form a fan shape and are arranged in four parallel in the surrounding direction, but this is not limited thereto. For example, the shape and arrangement of each region can be changed according to the required specifications.

[0075] In the first embodiment described above, an example was given in which a temperature sensor (40) is installed in each of the multiple areas (21 to 24), but this is not limited thereto. For example, the number and location of the temperature sensors (40) can be changed according to the required specifications.

[0076] In the first embodiment described above, the control device (5) monitors the detected temperatures of a plurality of temperature sensors (40) installed in a predetermined area and selects the one with the largest temperature change per unit time among the monitored multiple detected temperatures, but it is not limited to this.

[0077] In the first embodiment described above, the mounting portion (2) was described as being formed in a plate shape having a mounting surface (10) on the first surface (11), but it is not limited thereto. For example, the mounting portion (2) may be formed in a block shape having a mounting surface (10) on the first surface (11). For example, the shape of the mounting portion (2) can be changed according to the required specifications.

[0078] In the first embodiment described above, the temperature control unit (3) is described as being installed on a second surface (12) opposite to the side on which the mounting surface (10) is installed in the mounting unit (2), but this is not limited thereto. For example, the temperature control unit (3) may be built into the mounting unit (2). For example, the installation method of the temperature control unit (3) can be changed according to the required specifications.

[0079] In the first embodiment described above, the temperature sensor (40) is placed in the recess (13) of the mounting part (2) through the through hole (31) of the temperature control part (3) and is described as detecting the temperature of the area through the recess (13) of the mounting part (2), but this is not limited thereto. For example, the temperature sensor (40) may detect the temperature of the area without passing through the recess (13) of the mounting part (2). For example, the temperature sensor (40) may be a non-contact type temperature sensor. For example, the type of the temperature sensor (40) may be changed according to the required specifications.

[0080] In the first embodiment described above, as an example of a wafer temperature control device, a temperature control device (1) for controlling the temperature of a wafer (W) having a chip whose electrical characteristics are inspected by current flow (temperature of the wafer (W) that is locally heated by current flow) to a target temperature (SV) was described, but it is not limited thereto. For example, the temperature control device (1) may be applied to a temperature control device for controlling the temperature of a wafer (W) that does not have a chip whose electrical characteristics are inspected by current flow to a target temperature (SV). For example, the temperature control device (1) may be applied to a temperature control device for controlling the temperature of a wafer (W), such as a silicon wafer, to a target temperature (SV). For example, the temperature control device (1) may be used in a dry process. For example, the usage of the temperature control device may be changed according to the required specifications.

[0081] In the first embodiment described above, an example of performing speed-type PID control was explained, but it is not limited thereto. For example, PD control or the like may be performed instead of PID control.

[0082] Although the first embodiment of the present disclosure has been described above, the present disclosure is not limited to this first embodiment, and additions, omissions, substitutions, and other changes to the configuration are possible without departing from the spirit of the present disclosure, and it is also possible to appropriately combine the first embodiment described above.

[0083] <Second Embodiment>

[0084] Hereinafter, a second embodiment of the present disclosure will be described with reference to the drawings. In the second embodiment, FIGS. 1 to 3 are referenced, and the same reference numerals are assigned to parts identical to those in the first embodiment to omit redundant descriptions.

[0085] Temperature control device

[0086] As shown in FIG. 1, the temperature control device (1) comprises a mounting part (2), a temperature adjustment part (3), a temperature detection part (4) (see FIG. 3), and a control device (5). Each element of the temperature control device (1) is controlled by the control device (5).

[0087] Temperature Control Unit

[0088] The temperature control unit (3) can heat and cool the mounting unit (2). For example, the temperature control unit (3) independently adjusts the temperature of the mounting unit (2) for each of the multiple areas (21 to 24). For example, the temperature control unit (3) is equipped with a thermoelectric element (30), such as a Peltier element. For example, the thermoelectric element (30) is installed in each of the multiple areas (21 to 24). For example, by supplying power to the multiple thermoelectric elements (30), each area (21 to 24) can be independently heated and cooled. Each thermoelectric element (30) in each area (21 to 24) is controlled by a control device (5) (see FIG. 1). For example, a thermoelectric element (321) (see FIG. 12) is placed in region (21), a thermoelectric element (322) (see FIG. 12) is placed in region (22), a thermoelectric element (323) (see FIG. 12) is placed in region (23), and a thermoelectric element (324) (see FIG. 12) is placed in region (24).

[0089] Control Unit

[0090] FIG. 12 is a control block diagram of a control device in a second embodiment. The control device (5) controls the temperature adjustment unit (3) based on the detected temperature of a plurality of temperature sensors (40). For example, the control device (5) controls the temperature adjustment unit (3) by a speed-type PID controller (Proportional Integral Derivative Controller) to set the detected temperature of the temperature sensors (40) to a target temperature (SV). As shown in FIG. 12, the control device (5) is equipped with a plurality of operation amount change amount calculation units (71), a selection / switching unit (72), and a plurality of operation amount calculation units (73).

[0091] <Calculation unit for change in manipulated variable>

[0092] FIG. 13 is a control block diagram of a calculation unit for a change in the amount of manipulation in a second embodiment.

[0093] The operation amount change amount calculation unit (71) is installed for each of the plurality of temperature sensors (40). In the embodiment, the operation amount change amount calculation unit (71) is provided with a main operation amount change amount calculation unit (711m–714m) connected to the main temperature sensors (41m–44m) and a sub-operation amount change amount calculation unit (711s–714s) connected to the sub-temperature sensors (41s–44s). The main operation amount change amount calculation unit (711m–714m) and the sub-operation amount change amount calculation unit (711s–714s) receive a deviation e(k) (where “k” indicates the current sampling time) obtained by subtracting the target temperature (SV) from the respective detected temperatures of the main temperature sensors (41m–44m) and sub-temperature sensors (41s–44s) using a subtractor (74). As shown in FIG. 13, the change amount of the manipulated amount calculation unit (71) calculates the change amount of the P term dP(k), the change amount of the I term dI(k), and the change amount of the D term dD(k) using the deviation e(k) and the deviation e(k-1) from one sampling time prior. The change amount of the manipulated amount calculation unit (71) also calculates the change amount of the P term dP(k), the change amount of the I term dI(k), and the change amount of the D term dD(k) by adding these change amounts of the P term dP(k), the change amount of the I term dI(k), and the change amount of the D term dD(k).

[0094] The selection / switching unit (72) can switch from a state in which the change in amount of control calculated by one change in amount of control calculation unit (71) is selected to a state in which the change in amount of control calculated by another change in amount of control calculation unit (71) is selected. In the selection / switching unit (72) of the embodiment, as shown in FIG. 12, it is possible to switch between a state in which the change in amount of control calculated by the change in amount of control calculation unit (71) connected to the main temperature sensor is selected and a state in which the change in amount of control calculated by the change in amount of control calculation unit (71) connected to the secondary temperature sensor is selected.

[0095] In the second embodiment, the selection / switching unit (72) switches the selection state of two operation amount change amounts ΔMV(k), which are the calculation results of the main operation amount change amount calculation unit and the secondary operation amount change amount calculation unit corresponding to the main temperature sensor and the secondary temperature sensor installed in the same area, for example. That is, the selection / switching unit (72) of the embodiment selects either the operation amount change amount ΔMV(k) calculated by the main operation amount change amount calculation unit and the operation amount change amount ΔMV(k) calculated by the secondary operation amount change amount calculation unit. For example, the selection / switching unit (72) of the embodiment is configured to allow selection / switching individually for each corresponding area. For example, the selection / switching unit (72) of the embodiment switches the selection state to use the detection result of the temperature sensor (40) closer to the location where the disturbance is applied when the location where the disturbance is applied changes within the same area.

[0096] <Manipulated Quantity Calculation Unit>

[0097] FIG. 14 is a control block diagram of the operation amount calculation unit in the second embodiment.

[0098] The control amount calculation unit (73) calculates the control amount MV(k) of the temperature control unit (3) based on the control amount change amount ΔMV(k) selected by the selection / switching unit (72). The control amount calculation unit (73) is installed for each of the plurality of thermoelectric elements (30) installed in each area (21 to 24). For example, in an embodiment, the plurality of control amount calculation units (73) are provided with a control amount calculation unit (731) corresponding to area (21), a control amount calculation unit (732) corresponding to area (22), a control amount calculation unit (733) corresponding to area (23), and a control amount calculation unit (734) corresponding to area (24). As shown in FIG. 12, the change in amount of control ΔMV1 is input to the control amount calculation unit (731) as the change in amount of control ΔMV(k), the change in amount of control ΔMV2 is input to the control amount calculation unit (732), the change in amount of control ΔMV3 is input to the control amount calculation unit (733), and the change in amount of control ΔMV4 is input to the control amount calculation unit (734).

[0099] As shown in FIG. 14, the control amount calculation unit (73) calculates the current control amount MV(k) by adding the control amount change amount ΔMV(k) selected by the selection / switching unit (72) to the control amount MV(k-1) from one sampling time prior. As shown in FIG. 14, the control amount calculation unit (731) outputs the control amount (MV1) as the control amount MV(k) to the thermoelectric element (321), the control amount calculation unit (732) outputs the control amount (MV2) to the thermoelectric element (322), the control amount calculation unit (733) outputs the control amount (MV3) to the thermoelectric element (323), and the control amount calculation unit (734) outputs the control amount (MV4) to the thermoelectric element (324). Additionally, the control amount calculation unit (73) may have an anti-wind-up circuit (not shown).

[0100] Temperature Control Method

[0101] FIG. 15 is a flowchart of a temperature control method of a second embodiment. As shown in FIG. 15, the temperature control method of the embodiment includes a temperature monitoring process (S01), a wafer mounting process (S02), a wafer inspection process (S03), a process for calculating a change in the amount of manipulation (S14), a selection / switching process (S15), a process for calculating a amount of manipulation (S16), and a temperature adjustment process (S17).

[0102] In the temperature monitoring process (S01), the temperature is monitored at multiple locations in at least one of the multiple regions (21 to 24). For example, in the temperature monitoring process (S01), the temperature is monitored at multiple locations in each of the multiple regions (21 to 24). For example, in the temperature monitoring process (S01), all of the multiple temperature sensors (40) installed in each of the multiple regions (21 to 24) are constantly monitored. After the temperature monitoring process (S01), the process proceeds to the wafer mounting process (S02).

[0103] In the wafer mounting process (S02), a wafer (W) is mounted on a mounting surface (10) having a plurality of regions (21 to 24). For example, in the wafer mounting process (S02), a disc-shaped wafer (W) is mounted so as to overlap the entire surface with respect to a circular mounting surface (10) when viewed from a flat plane. After the wafer mounting process (S02), the process proceeds to a wafer inspection process (S03).

[0104] In the wafer inspection process (S03), an inspection of the wafer (W) mounted on the mounting surface (10) is initiated. For example, local heat input is generated as a disturbance applied by the inspection of the wafer (W). After the wafer inspection process (S03) is initiated, the process proceeds to the operation amount change amount calculation process (S14).

[0105] In the process of calculating the change in amount of manipulation (S14), the change in amount of manipulation ΔMV(k) for each location is calculated based on the detection temperature (wafer temperature) and target temperature (SV) of each location detected by the temperature monitoring process (S01). For example, in an embodiment, the change in amount of manipulation ΔMV(k) is calculated by adding the change in amount of P, the change in amount of I, and the change in amount of D, dD(k), by the change in amount of manipulation calculation unit (71).

[0106] In the selection and switching process (S15), among the changes in the amount of operation for each location calculated by the change in the amount of operation for each location calculated by the change in the amount of operation for each location, the state of selecting the change in the amount of operation for one location is switched to the state of selecting the change in the amount of operation for another location. In the embodiment, as described above, one of the two changes in the amount of operation ΔMV(k) calculated based on the detection temperature of the main temperature sensor and the auxiliary temperature sensor installed in the same area is selected. Additionally, if necessary, the state of selecting one of the two changes in the amount of operation ΔMV(k) is switched to the state of selecting the other. For example, in the selection and switching process (S15) of the embodiment, the selection and switching of the change in the amount of operation ΔMV(k) is performed for each area (21 to 24).

[0107] In the operation amount calculation process (S16), the operation amount MV(k) for temperature adjustment is calculated based on the operation amount change amount ΔMV(k) selected by the selection / switching process (S15). For example, in an embodiment, the operation amount calculation unit (73) calculates the current operation amount MV(k) by adding the operation amount change amount ΔMV(k) to the operation amount MV(k-1) from one sampling time prior.

[0108] In the temperature adjustment process (S17), the wafer temperature is adjusted based on the manipulated amount MV(k) calculated by the manipulated amount calculation process (S16). That is, the wafer (W) is heated or cooled using a thermoelectric element (30) in an area corresponding to the manipulated amount (MV) based on the calculated manipulated amount (MV).

[0109] FIG. 16 is a graph showing the temperature change and operation amount of the main temperature sensor and the negative temperature sensor in the second embodiment. In FIG. 16, the temperature change and operation amount in the second embodiment are shown as solid lines, and the temperature change and operation amount in the comparative example are shown as lines other than solid lines (dashed lines, single-dot dashed lines, double-dot dashed lines). In addition, FIG. 16 provides an example of a case where the temperature sensor (40) for feedback control of the temperature of the area (21) is switched from the main temperature sensor (41m) to the negative temperature sensor (41s). In addition, an example is provided of a case where the detected temperature of the main temperature sensor (41m) is higher than the detected temperature of the negative temperature sensor (41s).

[0110] As shown in FIG. 16, when the detected temperature of the main temperature sensor (41m) is adjusted to the target temperature (SV), the system switches from the main temperature sensor (41m) to the secondary temperature sensor (41s) (at the point of "sensor switching" in FIG. 16). By the selection / switching unit (72), the system switches from a state where the change in the amount of operation ΔMV(k) of the main operation amount change amount calculation unit (711m) is selected to a state where the change in the amount of operation ΔMV(k) of the secondary operation amount change amount calculation unit (711s) is selected. At this time, the operation amount (MV1) output from the operation amount calculation unit (731) of the embodiment is calculated by speed-type PID control, so it gradually increases over time, and the rate of increase decreases over time until it reaches a predetermined peak value. After that, the operation amount (MV1) gradually decreases over time, and the rate of decrease also gradually decreases until it becomes a constant operation amount (MV) that is the same as before the sensor switching point. As the thermoelectric element (321) is controlled by such an operation amount (MV1), the detected temperature of the negative temperature sensor (41s) gradually rises from the point of sensor switching and is adjusted so as not to exceed the target temperature (SV).

[0111] FIG. 17 is a control block diagram of a control device in a comparative example. In the comparative example, parts identical to those in the embodiment are described by assigning the same reference numerals. The temperature control device in the comparative example comprises a mounting unit (2) (see FIG. 3), a temperature adjustment unit (3) (see FIG. 3), a temperature detection unit (4) (see FIG. 3), and a control device (105) (see FIG. 17). In the temperature control device in the comparative example, similar to the second embodiment, the mounting surface (10) (see FIG. 2) is divided into four regions (21 to 24), and each region is equipped with one main temperature sensor and one auxiliary temperature sensor constituting the temperature detection unit (4). That is, a main temperature sensor (41m) and a negative temperature sensor (41s) are provided in area (21), a main temperature sensor (42m) and a negative temperature sensor (42s) are provided in area (22), a main temperature sensor (43m) and a negative temperature sensor (43s) are provided in area (23), and a main temperature sensor (44m) and a negative temperature sensor (44s) are provided in area (24).

[0112] The control device (105) controls the temperature adjustment unit (3) (thermoelectric element (30)) based on the detected temperature of a plurality of temperature sensors (40). For example, the control device (105) controls the temperature by PID control (Proportional Integral Derivative Controller) to make the detected temperature of the temperature sensor (40) the target temperature (SV). As shown in FIG. 17, the control device (105) is equipped with a selection / switching unit (172), a subtractor (74), and an operation amount calculation unit (173 to 176). The selection / switching unit (172) is configured to switch between the main temperature sensor and the secondary temperature sensor for each region to enable the selection of one of the detected temperatures. The detected temperature selected by the selection / switching unit (172) is input to the operation amount calculation unit (173 to 176) respectively through the subtractor (74) for each region. The control amount calculation unit (173-176) calculates the control amounts (MV1-MV4) of the temperature control unit (3) by PID control based on the input from the subtractor (74).

[0113] As shown in FIG. 16, in a comparative example having the above configuration, for example, when switching from the main temperature sensor (41m) to the negative temperature sensor (41s) by the selection / switching unit (172), a so-called switching shock occurs. Specifically, the operating amount (MV1) of the thermoelectric element (321) (indicated by a dashed line in FIG. 16) rises approximately vertically from the point of sensor switching, and when it reaches a peak value higher than the peak of the aforementioned operating amount (MV1) (for example, more than twice the MV1), it drops sharply and decreases from the operating amount (MV) before the point of sensor switching, and then becomes a constant operating amount (MV1) before the point of sensor switching. When the thermoelectric element (321) is controlled by the amount of manipulation (MV) of such a comparative example, the detected temperature of the negative temperature sensor (41s) (indicated by a dotted line in FIG. 16) rises sharply from the point of sensor switching and is adjusted to the target temperature (SV) after exceeding (overshooting) the target temperature (SV).

[0114] <Effects of Action>

[0115] As described above, the wafer temperature control device (1) of the second embodiment comprises a mounting part (2) having a mounting surface (10) on which a wafer (W) is mounted, a temperature control part (3) capable of heating and cooling the mounting part (2), a plurality of temperature sensors (40) installed on the mounting part (2), and a control device (5) for controlling the temperature control part (3). The control device (5) is provided with a plurality of operation amount change amount calculation units (71) that are installed for each of the plurality of temperature sensors (40) and calculate the operation amount change amount ΔMV(k) of the temperature adjustment unit (3) based on the detected temperature and target temperature (SV) of the temperature sensor (40), a selection / switching unit (72) that can switch from a state in which the operation amount change amount ΔMV(k) calculated by one operation amount change amount calculation unit (71) is selected to a state in which the operation amount change amount ΔMV(k) calculated by another operation amount change amount calculation unit (71) is selected, and an operation amount calculation unit (73) that calculates the operation amount MV(k) of the temperature adjustment unit (3) based on the operation amount change amount ΔMV(k) selected by the selection / switching unit (72).

[0116] According to this configuration, when switching from a state in which a change in amount of control ΔMV(k) calculated by one change in amount of control calculation unit (71) is selected to a state in which a change in amount of control ΔMV(k) calculated by another change in amount of control calculation unit (71) is selected, the change in amount of control MV(k) at the time of switching can be made smaller compared to the case where the change in amount of control MV(k) is switched. By doing so, the time until the temperature of the wafer (W) is adjusted to the target temperature (SV) is not extended, and the wafer temperature can be suppressed from overshooting relative to the target temperature (SV).

[0117] In addition, in the second embodiment, the plurality of temperature sensors (40) are composed of main temperature sensors (41m to 44m) and auxiliary temperature sensors (41s to 44s), and the plurality of operation amount change amount calculation units (71) are provided with a main operation amount change amount calculation unit (711m to 714m) that calculates the operation amount change amount ΔMV(k) of the temperature adjustment unit (3) based on the detection temperature of the main temperature sensors (41m to 44m) and the target temperature (SV), and an auxiliary operation amount change amount calculation unit (711s to 714s) that calculates the operation amount change amount ΔMV(k) of the temperature adjustment unit (3) based on the detection temperature of the auxiliary temperature sensors (41s to 44s) and the target temperature (SV). The selection / switching unit (72) selects either the change in amount of operation ΔMV(k) calculated by the main change in amount of operation calculation unit (711m to 714m) or the change in amount of operation ΔMV(k) calculated by the sub-change in amount of operation calculation unit (711s to 714s).

[0118] Thus, when switching between temperature control based on the main temperature sensor and temperature control based on the negative temperature sensor, the amount of change of the control amount MV(k) can be reduced, thereby suppressing the wafer temperature from overshooting relative to the target temperature (SV).

[0119] In addition, in the second embodiment, the mounting surface (10) is divided into a plurality of regions (21–24) when viewed from a planar view, and the thermoelectric element (30) of the temperature control unit (3), the main temperature sensor (41m–44m), and the secondary temperature sensor (41s–44s) are installed in each region (21–24). The operation amount calculation unit (73) is installed for each of the plurality of thermoelectric elements (321–324) of the temperature control unit (3), the main operation amount change amount calculation unit (711m–714m) is installed for each of the plurality of main temperature sensors (41m–44m), and the secondary operation amount change amount calculation unit (711s–714s) is installed for each of the plurality of secondary temperature sensors (41s–44s). The selection / switching unit (72) selects one of the change in operation amount ΔMV(k) calculated by the main operation amount change amount calculation unit (711m-714m) and the change in operation amount ΔMV(k) calculated by the sub-operation amount change amount calculation unit (711s-714s) for each of the multiple areas (21-24) and outputs it to the operation amount calculation unit (731-734).

[0120] According to this configuration, since there is no need to install the same number of operation amount calculation units (731-734) as the temperature sensor (40) or the operation amount change amount calculation unit (71), the circuit configuration of the control device (5) can be simplified.

[0121] In addition, in the second embodiment, the control device (5) performs speed-type PID control by means of the control amount change amount calculation unit (71) and the control amount calculation unit (73).

[0122] Thus, the temperature of the wafer (W) can be rapidly adjusted to the target temperature (SV) while reducing the deviation between the temperature of the wafer (W) and the target temperature (SV).

[0123] In a wafer temperature control method according to a second embodiment, the method comprises: a temperature monitoring process (S01) for detecting wafer temperatures at multiple locations; a process for calculating a change in operation amount ΔMV(k) at each location based on the wafer temperatures at multiple locations and a target temperature (SV) detected by the temperature monitoring process (S01); a selection / switching process (S15) for switching from a state in which a change in operation amount ΔMV(k) at one location is selected to a state in which a change in operation amount ΔMV(k) at another location is selected among the change in operation amount ΔMV(k) at each location calculated by the change in operation amount calculation process (S14); a process for calculating a change in operation amount MV(k) for temperature adjustment based on the change in operation amount ΔMV(k) selected by the selection / switching process (S15); and a method for controlling the temperature of a wafer (W) based on the change in operation amount MV(k) calculated by the change in operation amount calculation process (S16). It includes a temperature adjustment process (S17) for adjustment.

[0124] According to this configuration, the amount of change in the control amount MV(k) during switching can be reduced compared to when the control amount MV(k) is switched. By doing so, the time until the wafer (W) temperature is adjusted to the target temperature (SV) is not extended, and the wafer temperature can be suppressed from overshooting relative to the target temperature (SV).

[0125] (A variation of the second embodiment)

[0126] In the second embodiment described above, an example was given in which the mounting surface is formed in a circular shape when viewed from a planar view, but this is not limited thereto. For example, the mounting surface may be formed in a rectangular shape when viewed from a planar view. For example, the shape of the mounting surface when viewed from a planar view can be changed according to required specifications, such as the shape of the wafer (W).

[0127] In the second embodiment, an example was described in which a plurality of temperature sensors (40) are spaced apart from each other in the peripheral direction and the diameter direction of the mounting surface when viewed from a planar view, but this is not limited thereto. For example, the plurality of temperature sensors (40) do not need to be spaced apart from each other in the peripheral direction and the diameter direction of the mounting surface when viewed from a planar view. For example, the arrangement of the plurality of temperature sensors (40) can be changed according to the required specifications.

[0128] In the second embodiment, an example was described in which a plurality of regions (21 to 24) form a fan shape and are arranged in four parallel in the surrounding direction, but this is not limited thereto. For example, the shape and arrangement of each region can be changed according to the required specifications.

[0129] In the second embodiment, an example was described in which a temperature sensor (40) is installed in each of the multiple areas (21 to 24), but this is not limited thereto. For example, the number and location of the temperature sensors (40) can be changed according to the required specifications.

[0130] In the second embodiment, the control device (5) monitors the detected temperatures of a plurality of temperature sensors (40) installed in a predetermined area and selects the one with the largest temperature change per unit time among the monitored plurality of detected temperatures, but this is not limited thereto.

[0131] In the second embodiment, an example was described in which the mounting portion (2) is formed in a plate shape having a mounting surface (10) on the first surface (11), but it is not limited thereto. For example, the mounting portion (2) may be formed in a block shape having a mounting surface (10) on the first surface (11). For example, the shape of the mounting portion (2) can be changed according to the required specifications.

[0132] In the second embodiment, the temperature control unit (3) is described as being installed on a second surface (12) opposite to the side on which the mounting surface (10) is installed in the mounting unit (2), but this is not limited thereto. For example, the temperature control unit (3) may be built into the mounting unit (2). For example, the installation method of the temperature control unit (3) can be changed according to the required specifications.

[0133] In the second embodiment, the temperature sensor (40) is placed in the recess (13) of the mounting part (2) through the through hole (31) of the temperature control part (3) and is described as detecting the temperature of the area through the recess (13) of the mounting part (2), but this is not limited thereto. For example, the temperature sensor (40) may detect the temperature of the area without passing through the recess (13) of the mounting part (2). For example, the temperature sensor (40) may be a non-contact type temperature sensor. For example, the type of the temperature sensor (40) may be changed according to the required specifications.

[0134] In the second embodiment, as an example of a wafer temperature control device, a temperature control device (1) for controlling the temperature of a wafer (W) having a chip whose electrical characteristics are inspected by current flow (temperature of the wafer (W) that is locally heated by current flow) to a target temperature (SV) was described, but it is not limited thereto. For example, the temperature control device (1) may be applied to a temperature control device for controlling the temperature of a wafer (W) that does not have a chip whose electrical characteristics are inspected by current flow to a target temperature (SV). For example, the temperature control device (1) may be applied to a temperature control device for controlling the temperature of a wafer (W), such as a silicon wafer, to a target temperature (SV). For example, the temperature control device (1) may be used in a dry process. For example, the usage of the temperature control device may be changed according to the required specifications.

[0135] In the second embodiment, an example of performing speed-type PID control was described, but it is not limited thereto. For example, PD control or the like may be performed instead of PID control.

[0136] Although a second embodiment of the present disclosure has been described above, the present disclosure is not limited to the second embodiment, and additions, omissions, substitutions, and other changes to the configuration are possible without departing from the spirit of the present disclosure, and it is also possible to appropriately combine the aforementioned second embodiment. Industrial applicability

[0137] According to the present disclosure, the wafer temperature can be adjusted to the target temperature more quickly after the application of a local thermal outflow is stopped. In addition, the occurrence of overshoot can be suppressed. Explanation of the symbols

[0138] 1: Temperature control device 2: Mounting section 3: Temperature control unit 4: Temperature detection unit 5: Control unit 10: Mounting surface 11: Page 1 12: Page 2 13: Concave part 21∼24: Area 30: Thermoelectric element 31: Penetrating hole 35: Cooling section 36: Cooling furnace 37: Shovel hole 40: Temperature sensor 41m∼44m: Ambient temperature sensor 41s~44s: Negative temperature sensor 51: Calculation unit for change in manipulated variable 52: Selection / Transition Section 53: Manipulated variable calculation unit 54: Subtractor 71: Calculation unit for change in manipulated variable 72: Selection / Transition Section 73: Manipulated variable calculation unit 74: Subtractor 105: Control unit 152: Selection / Transition Section 153∼156: Manipulated quantity calculation section 172: Selection / Transition Section 173∼176: Manipulated quantity calculation section 321∼324: Thermoelectric elements 511m∼514m: Calculation section for change in main manipulation amount 511s∼514s: Calculation section for change in unmanipulated quantity 531∼534: Manipulated quantity calculation section 711m∼714m: Calculation section for change in main manipulation amount 711s∼714s: Calculation section for change in unmanipulated quantity 731∼734: Manipulated quantity calculation section S01: Temperature monitoring process S02: Wafer Mounting Process S03: Wafer Inspection Process S04: Process for calculating the change in manipulated variable S05: Selection and Switching Process S06: Process for calculating manipulated variable S07: Temperature control process S14: Process for calculating the change in manipulated variable S15: Selection and Switching Process S16: Process for calculating manipulated variable S17: Temperature control process SV: Target temperature W: Wafer

Claims

Claim 1 A wafer temperature control device comprising: a mounting section having a mounting surface capable of mounting a wafer, wherein the mounting surface is divided into a plurality of regions when viewed from a planar perspective; a temperature control section for independently adjusting the temperature of the plurality of regions; a plurality of temperature sensors installed in each of the plurality of regions and detecting the temperature of the region; a temperature control section for independently controlling the temperature of the plurality of regions by the temperature control section; and a disturbance detection section for detecting the application of a disturbance to the region based on the detected temperature of the temperature sensor, and a switching section for feeding back only the detected temperature of the temperature sensor installed in the region where the disturbance application is detected to the temperature control section when the application of a disturbance is detected by the disturbance detection section; wherein the temperature control section adjusts the temperature of the plurality of regions based on the detected temperature fed back by the plurality of temperature sensors during normal operation, and adjusts the temperature of the plurality of regions based on the detected temperature fed back by the switching section when a disturbance is applied. Claim 2 A wafer temperature control device according to claim 1, wherein the switching unit feeds back the detected temperature of the temperature sensor installed in each of the plurality of regions to the temperature control unit that controls the temperature adjustment unit of the region where each temperature sensor is installed, when the disturbance application is not detected in any of the plurality of regions. Claim 3 A wafer temperature control device according to claim 1, wherein the temperature sensors are installed in a plurality of areas, and further comprises a detection temperature selection unit that selects the temperature with a large change per unit time among the detection temperatures of the plurality of temperature sensors. Claim 4 A wafer temperature control method comprising a disturbance detection process for detecting the application of a disturbance to a wafer in which a plurality of regions are set when viewed from a planar view, and a disturbance suppression operation process for independently feedback-controlling the temperature of all regions based on the detected temperature of one region in which the disturbance application is detected when the application of a disturbance is detected. Claim 5 A wafer temperature control method according to claim 4, comprising a normal operation process for independently feedback controlling the temperatures of a plurality of regions based on the detected temperatures of each region when no disturbance is detected in any region of the wafer. Claim 6 A wafer temperature control device comprising: a mounting unit having a mounting surface on which a wafer is mounted; a temperature control unit capable of heating and cooling the mounting unit; a plurality of temperature sensors installed in the mounting unit; and a temperature control device for controlling the temperature control unit; wherein the temperature control device comprises: a plurality of operation amount change amount calculation units installed for each of the plurality of temperature sensors and calculating an operation amount change amount of the temperature control unit based on the detected temperature of the temperature sensor and a target temperature; a selection / switching unit capable of switching from a state in which an operation amount change amount calculated by one of the operation amount change amount calculation units is selected to a state in which an operation amount change amount calculated by another operation amount change amount calculation unit is selected; and an operation amount calculation unit that calculates an operation amount of the temperature control unit based on the operation amount change amount selected by the selection / switching unit. Claim 7 In claim 6, the plurality of temperature sensors comprises a main temperature sensor and a secondary temperature sensor, and the plurality of operation amount change amount calculation units comprises a main operation amount change amount calculation unit that calculates the operation amount change amount of the temperature adjustment unit based on the detected temperature and target temperature of the main temperature sensor, and a secondary operation amount change amount calculation unit that calculates the operation amount change amount of the temperature adjustment unit based on the detected temperature and target temperature of the secondary temperature sensor, and the selection / switching unit selects either the operation amount change amount calculated by the main operation amount change amount calculation unit or the operation amount change amount calculated by the secondary operation amount change amount calculation unit. Claim 8 A wafer temperature control device according to claim 7, wherein the mounting surface is divided into a plurality of regions when viewed from a planar view, the temperature control unit, the main temperature sensor, and the auxiliary temperature sensor are installed in each of the regions, the operation amount calculation unit is installed in each of the plurality of the temperature control units, the main operation amount change amount calculation unit is installed in each of the plurality of the main temperature sensors, the auxiliary operation amount change amount calculation unit is installed in each of the plurality of the auxiliary temperature sensors, and the selection / switching unit selects either the operation amount change amount calculated by the main operation amount change amount calculation unit and the operation amount change amount calculated by the auxiliary operation amount change amount calculation unit for each of the plurality of regions and outputs it to the operation amount calculation unit. Claim 9 In claim 6, the temperature control device comprises the control amount change amount calculation unit and the wafer temperature control device that performs velocity-type PID control by the control amount calculation unit. Claim 10 A method for controlling the temperature of a wafer, comprising: a temperature monitoring process for detecting wafer temperatures at multiple locations; a process for calculating a change in amount of manipulation at each location based on the wafer temperature at each location and a target temperature detected by the temperature monitoring process; a selection and switching process for switching from a state in which a change in amount of manipulation at one location is selected to a state in which a change in amount of manipulation at another location is selected among the change in amount of manipulation at each location calculated by the change in amount of manipulation at each location; a process for calculating a change in amount of manipulation for temperature adjustment based on the change in amount of manipulation selected by the selection and switching process; and a temperature adjustment process for adjusting the wafer temperature based on the change in amount of manipulation calculated by the change in amount of manipulation.

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