JP5485936B2 - Temperature calibration apparatus and temperature calibration method - Google Patents

Description

  The present invention relates to a temperature calibration device for calibrating the temperature of a heat treatment mechanism for a heat treatment device that heats a substrate to a predetermined temperature using a heat treatment mechanism, and a temperature calibration method using the temperature calibration device. The calibration referred to here means measuring the temperature of the heat treatment mechanism and adjusting the temperature of the heat treatment mechanism to a desired value.

  In a photolithography process in the manufacturing process of a semiconductor device, a heat treatment (pre-baking process) after applying a resist solution on a semiconductor wafer (hereinafter referred to as “wafer”), a predetermined pattern is exposed on the resist film Various heat treatments such as heat treatment (post-exposure baking treatment) and heat treatment (post-baking treatment) after developing the exposed resist film are performed. In addition, heat treatment for adjusting the temperature of the wafer is also performed after the heat treatment. Further, in plasma processing such as etching processing and film formation processing, heat processing for adjusting the temperature of the wafer is performed.

  The heat treatment described above is performed, for example, by placing a wafer on a heat treatment plate set at a predetermined temperature in a heat treatment apparatus. In order to appropriately perform this heat treatment, it is important to measure the temperature distribution of the wafer on the heat treatment plate in advance and appropriately correct the temperature of the heat treatment plate based on the measurement result. Therefore, conventionally, the temperature of the wafer in this heat treatment has been measured.

  Various measuring apparatuses have been used for measuring the temperature of the wafer. When a wired measurement device is used, a plurality of temperature sensors are provided on the wafer, and the temperature sensor and an external measurement circuit are connected by a cable. In such a case, the conveyance of the wafer is limited by the cable, and the control for the conveyance becomes complicated. In addition, the space for heat treatment by this cable cannot be a sealed space, and the processing space that should be measured cannot be reproduced, so that accurate temperature measurement cannot be performed.

  When a wireless measurement device is used, both the temperature sensor and the measurement circuit are provided on the wafer. In such a case, since a large number of components are mounted on the wafer, the structure becomes complicated, and these measurement circuits may malfunction at high temperatures. In addition, since the volume (thickness) of the entire wafer is increased, the wafer may interfere with other devices when the wafer is transferred or when the temperature is measured.

  Therefore, Patent Document 1 proposes to use a wafer type temperature sensor in which a plurality of temperature sensors and contacts that output sensor outputs of the plurality of temperature sensors as output signals are provided on the wafer surface. In such a case, a contact provided inside the heat treatment apparatus is brought into contact with a contact on the wafer. An output signal from the contact is output to a data management unit provided outside the heat treatment apparatus via a contact. The data management unit determines the temperature of the wafer based on the output signal.

JP 2007-187619 A

  However, when the method of Patent Document 1 described above is used, the wafer type temperature sensor is not arranged at a predetermined position on the heat treatment plate, that is, the wafer type temperature sensor is rotated on the heat treatment plate in a horizontal plane from the predetermined position. It may be placed on. In such a case, the contact on the wafer type temperature sensor is not arranged at a predetermined position, and the contact does not properly contact the contact. If it does so, the sensor output of a temperature sensor will not be output to a data management part, but the temperature of a wafer cannot be measured appropriately.

  The present invention has been made in view of this point, and an object of the present invention is to appropriately calibrate the temperature of the heat treatment mechanism in a heat treatment apparatus that heats the substrate to a predetermined temperature using the heat treatment mechanism.

  In order to achieve the above object, the present invention provides a temperature calibration apparatus for calibrating the temperature of the heat treatment mechanism with respect to a heat treatment apparatus that heat-treats the substrate to a predetermined temperature using a heat treatment mechanism. A plurality of resistance thermometers provided on the substrate, the resistance value of which varies according to a temperature change, and provided on the substrate, electrically connected to the resistance thermometer, and temperature measurement of the substrate A plurality of contact pads that sometimes contact the contact, and a control unit that measures the temperature of the substrate based on the resistance value of the resistance temperature detector measured through the contact pad and the contact. The plurality of contact pads are arranged continuously along the peripheral edge of the substrate. The controller may adjust the temperature of the heat treatment mechanism based on the measured temperature of the substrate.

  According to the present invention, first, a contact is brought into contact with the contact pad on the substrate, and the resistance value of the resistance temperature detector is measured through the contact pad and the contact. At this time, since the contact pads are continuously arranged along the peripheral edge of the substrate, even if, for example, the substrate is rotated in a horizontal plane from a predetermined position, the contactor reliably contacts the contact pads. . For this reason, the resistance value of the resistance temperature detector is reliably measured. Next, based on the measured resistance value of the resistance temperature detector, the temperature of the substrate is measured. The temperature of the heat treatment mechanism can be adjusted based on the measured substrate temperature. Thus, according to the present invention, it is possible to appropriately measure the temperature of the substrate and appropriately adjust the temperature of the heat treatment mechanism. Then, the subsequent heat treatment mechanism can appropriately perform the heat treatment on the subsequent substrate.

  The temperature calibration device is provided on the substrate, the resistance value does not change according to a temperature change, and the reference resistor has a resistance value dissociated by a predetermined amount or more from the resistance value of the resistance temperature detector, A plurality of reference contact pads provided on a substrate, electrically connected to the reference resistor, and contacted by a contact when measuring the temperature of the substrate, the plurality of contact pads and the plurality of references The contact pads may be continuously arranged along the peripheral edge of the substrate.

  A plurality of the resistance temperature detectors may form a Wheatstone bridge circuit, and the control unit may adjust the temperature of the heat treatment mechanism so that the Wheatstone bridge circuit is in an equilibrium state. Note that the Wheatstone bridge circuit is in a balanced state means a state where the potential difference between the midpoints of the Wheatstone bridge circuit becomes zero, that is, a state where the offset voltage of the Wheatstone bridge circuit becomes zero.

  The controller may adjust the temperature of the heat treatment mechanism so that a current value in the Wheatstone bridge circuit becomes a predetermined value.

  A plurality of Wheatstone bridge circuits may be formed, and the controller may adjust the temperature of the heat treatment mechanism so that the current values in the plurality of Wheatstone bridge circuits are equal.

  The heat treatment mechanism may be divided into a plurality of regions, and the temperature may be adjustable for each region.

  The resistance temperature detector and the contact pad may be arranged at a predetermined distance apart in the horizontal direction.

  The contact pads may be arranged at a predetermined distance from the surface of the substrate in the vertical direction.

  A heat insulating layer may be formed on the surface of the substrate and immediately below the contact pad.

  The heat treatment apparatus includes a lid member provided so as to be movable up and down above the heat treatment mechanism, the contact is disposed on a lower surface of the lid member so as to face the contact pad, and the lid member is a predetermined member. The contact pad may come into contact with the contact when lowered to the position.

  The present invention according to another aspect is a temperature calibration method for calibrating the temperature of the heat treatment mechanism using a temperature calibration device with respect to a heat treatment device that heat-treats the substrate to a predetermined temperature using the heat treatment mechanism, A plurality of resistance temperature detectors provided on the substrate, the resistance value of which changes according to a temperature change, and continuously arranged along a peripheral edge on the substrate, and electrically connected to the resistance temperature detector And the contact pads on the substrate placed on the heat treatment mechanism using the temperature calibration device configured to include a plurality of contact pads that contact with the contacts when measuring the temperature of the substrate. A first step of measuring the resistance value of the resistance temperature detector via the contact pad and the contact, and measuring the temperature of the substrate based on the measured resistance value of the resistance temperature detector A second step of: It is characterized by performing.

  The temperature calibration device is provided on the substrate, the resistance value does not change according to a temperature change, and the reference resistor has a resistance value dissociated by a predetermined amount or more from the resistance value of the resistance temperature detector, A plurality of reference contact pads provided on a substrate, electrically connected to the reference resistor, and contacted by a contact when measuring the temperature of the substrate, the plurality of contact pads and the plurality of references Contact pads are continuously arranged along the peripheral edge of the substrate. In the first step, the contact is brought into contact with the reference contact pad, and the reference resistance is connected to the reference contact pad and the contact. Body resistance may be measured.

  The temperature calibration method may include a third step of adjusting the temperature of the heat treatment mechanism based on the measured temperature of the substrate.

  A plurality of the resistance temperature detectors may form a Wheatstone bridge circuit, and in the third step, the temperature of the heat treatment mechanism may be adjusted so that the Wheatstone bridge circuit is in an equilibrium state.

  In the third step, the temperature of the heat treatment mechanism may be adjusted so that a current value in the Wheatstone bridge circuit becomes a predetermined value.

  A plurality of Wheatstone bridge circuits may be formed, and in the third step, the temperature of the heat treatment mechanism may be adjusted so that the current values in the plurality of Wheatstone bridge circuits are equal.

  The heat treatment mechanism may be partitioned into a plurality of regions, and the temperature can be adjusted for each region. In the third step, the temperature of the heat treatment mechanism may be adjusted for each region.

  The resistance temperature detector and the contact pad may be arranged at a predetermined distance apart in the horizontal direction.

  The contact pads may be arranged at a predetermined distance from the surface of the substrate in the vertical direction.

  A heat insulating layer may be formed on the surface of the substrate and immediately below the contact pad.

  The heat treatment apparatus includes a lid member provided so as to be movable up and down above the heat treatment mechanism, and the contact is disposed on a lower surface of the lid member so as to face the contact pad, the first step In this case, the contact pad and the contact may come into contact when the lid member is lowered to a predetermined position.

  According to the present invention, in the heat treatment apparatus for heat-treating the substrate to a predetermined temperature using the heat treatment mechanism, the temperature of the heat treatment mechanism can be appropriately calibrated.

It is explanatory drawing which shows the outline of a structure of the temperature calibration apparatus and heat processing apparatus concerning this Embodiment. It is a top view which shows the outline of a structure of a heat processing board. It is a top view which shows the outline of a structure of a temperature test jig | tool. It is a side view which shows the outline of a structure of a temperature test jig | tool. It is a top view which shows the outline of a structure of the temperature test jig | tool concerning other embodiment. It is a top view which shows the outline of a structure of the temperature test jig | tool concerning other embodiment. It is explanatory drawing which shows the outline of a structure of a Wheatstone bridge circuit. It is a top view which shows the outline of a structure of the temperature test jig | tool concerning other embodiment. It is a top view which shows the outline of a structure of the temperature test jig | tool concerning other embodiment. It is a side view which shows the outline of a structure of the temperature test jig | tool concerning other embodiment. It is a longitudinal cross-sectional view which shows the outline of a structure of the temperature inspection jig | tool concerning other embodiment.

  Embodiments of the present invention will be described below. FIG. 1 is an explanatory diagram showing an outline of the configuration of a temperature calibration apparatus 1 according to the present embodiment and a heat treatment apparatus 2 to which the temperature calibration apparatus 1 is applied. The temperature calibration device 1 has a temperature inspection jig 10 that adjusts the temperature of a heat treatment plate 50 as a heat treatment mechanism described later with respect to the heat treatment device 2 and is placed on the heat treatment plate 50. The heat treatment apparatus 2 places a wafer W as a substrate on the heat treatment plate 50 and performs heat treatment on the wafer W.

  As shown in FIG. 1, the heat treatment apparatus 2 includes a processing container 20 having a temperature inspection jig 10 or a wafer W loading / unloading port (not shown) formed on a side surface. In the processing container 20, there is a lid member 30 which is located on the upper side and can be moved up and down in the vertical direction, and a hot plate accommodating part 31 which is located on the lower side and forms the processing chamber K integrally with the lid member 30. Is provided.

  The lid member 30 has a substantially cylindrical shape. A protrusion 40 is formed on the outer periphery of the lower surface of the lid member 30, and the protrusion 40 abuts on the hot plate container 31 to form a processing chamber K. In addition, a plurality of contacts 41 such as pogo pins that extend vertically downward are provided on the lower surface of the lid member 30. The contactor 41 is made of a conductive material. The plurality of contacts 41 are arranged corresponding to (opposed to) contact pads 72 described later of the temperature inspection jig 10. That is, the plurality of contacts 41 are arranged along the peripheral edge of the wafer 70 to be described later. In the example of FIG. 1, the arrangement of the contacts 41 in one section is shown. In addition, an exhaust part 42 is provided at the center of the upper surface of the lid member 30. The atmosphere in the processing chamber K is uniformly exhausted from the exhaust unit 42.

  The hot plate accommodating portion 31 includes an annular holding member 51 that holds the heat treatment plate 50 and holds the outer peripheral portion of the heat treatment plate 50, and a substantially cylindrical support ring 52 that surrounds the outer periphery of the holding member 51.

As shown in FIG. 2, the heat treatment plate 50 is divided into a plurality of, for example, four hot plate regions R ₁ , R ₂ , R ₃ , and R ₄ . For example, the heat treatment plate 50 is divided into four equal parts in a plan view. That is, each of the hot plate regions R ₁ , R ₂ , R ₃ , R ₄ has a fan shape with a central angle of 90 degrees.

Each of the hot plate regions R _{1 to} R ₄ of the heat treatment plate 50 has a built-in heater 53 that generates heat by electric supply, and can be heated for each of the hot plate regions R _{1 to} R ₄ . The amount of heat generated by the heater 53 in each of the hot plate regions R _{1 to} R ₄ is adjusted by the control unit 100 described later. The controller 100 can control the temperature of each of the hot plate regions R _{1 to} R ₄ to a predetermined temperature by adjusting the amount of heat generated by the heater 53.

  As shown in FIG. 1, below the heat treatment plate 50, lift pins 60 are provided to support the temperature inspection jig 10 or the wafer W from below and lift it. The lift pins 60 can be moved up and down in the vertical direction by the lift drive mechanism 61. In the vicinity of the center portion of the heat treatment plate 50, a through hole 62 that penetrates the heat treatment plate 50 in the thickness direction is formed. The elevating pins 60 can be raised from below the heat treatment plate 50, pass through the through holes 62, and protrude above the heat treatment plate 50.

  Next, the configuration of the temperature calibration device 1 will be described. The temperature calibration apparatus 1 has a temperature inspection jig 10 placed on the heat treatment plate 50 as shown in FIG. The temperature inspection jig 10 has a processing target wafer 70 as a substrate as shown in FIG. The wafer 70 to be processed is made of the same material as the wafer W, for example, silicon, and has the same planar shape as the wafer W. In order to measure an accurate temperature, it is desirable that the processing target wafer 70 is the same as the actual wafer W. However, the present invention is not limited to this, and the shape, material, and the like may be different.

  A plurality of, for example, four resistance thermometers 71, a plurality of, for example, eight contact pads 72, and a wiring 73 that electrically connects the resistance thermometer 71 and the contact pads 72 are formed on the wafer 70 to be processed. Yes. The resistance temperature detector 71, the contact pad 72, and the wiring 73 are collectively formed by performing a photolithography process on the wafer 70 to be processed, for example. When the wafer 70 to be processed is a conductor, the surface may be sufficiently insulated before these elements are formed.

  The resistance temperature detector 71 is a resistor whose resistance value changes with temperature change, and for example, an RTD (Resistance Temperature Detector) or a thermistor is used. The resistance temperature detector 71 is disposed at a temperature measurement point of the wafer 70 to be processed. The arrangement and number of the resistance temperature detectors 71 are not limited to the present embodiment and can be arbitrarily set.

  As shown in FIG. 4, the contact 41 contacts the contact pad 72 when the temperature of the heat treatment plate 50 is adjusted. The contact pad 72 is made of a conductive material such as aluminum. As shown in FIG. 3, two contact pads 72 are provided for one resistance temperature detector 71. That is, the resistance value of the resistance temperature detector 71 is measured by a so-called two-wire connection type. One contact pad 72 functions as a positive electrode, and the other contact pad 72 functions as a negative electrode.

  Further, the plurality of contact pads 72 are continuously arranged along the peripheral edge of the wafer 70 to be processed. Further, the contact pad 72 is disposed away from the resistance temperature detector 71 by a predetermined distance D in the horizontal direction. The predetermined distance D is set to a distance at which the resistance thermometer 71 is not affected by the temperature change due to the contact of the contact 41 when the contact 41 contacts the contact pad 72. That is, in the present embodiment, the temperature of the processing target wafer 70 does not decrease in the region where the resistance temperature detector 71 is provided by the contact of the contact 41. Since the contact 41 does not come into contact with the actually processed wafer W, the actual temperature of the wafer W can be accurately measured in this way. The predetermined distance D is set according to the material of the wafer 70 to be processed, the heat treatment temperature, and the like. For example, silicon having a diameter of 300 mm is used for the wafer 70 to be processed, and when the heat treatment temperature of the wafer 70 to be processed is 150 ° C., the predetermined distance D is, for example, 20 mm.

  For example, aluminum is used for the wiring 73 in the same manner as the contact pad 72.

  Moreover, the temperature calibration apparatus 1 has the control part 100 provided in the exterior of the heat processing apparatus 2, as shown in FIG. The control unit 100 is, for example, a computer, and includes a measurement circuit including, for example, a processor, a memory, an amplifier, a switch, and the like. With this measurement circuit, the control unit 100 can measure the resistance value of the resistance temperature detector 71 and the like. Further, the control unit 100 has a program storage unit (not shown). In the program storage unit, for example, a program for adjusting the temperature of the heat treatment plate 50 (the amount of heat generated by the heater 53) based on the resistance value of the resistance temperature detector 71 is stored. The program is recorded on a computer-readable storage medium such as a computer-readable hard disk (HD), flexible disk (FD), compact disk (CD), magnetic optical desk (MO), or memory card. Or installed in the control unit 100 from the storage medium. Further, when the heat treatment apparatus 2 itself has a temperature adjustment mechanism for adjusting the temperature of the heat treatment plate 50, the control unit 100 controls the temperature adjustment mechanism based on the measured temperature. Also good. What is necessary is just to respond | correspond suitably according to the function which the heat processing apparatus 2 has.

  Next, a method for adjusting the temperature of the heat treatment plate 50 of the heat treatment apparatus 2 using the temperature calibration apparatus 1 configured as described above will be described.

First, the temperature inspection jig 10 is carried into the heat treatment apparatus 2. The temperature inspection jig 10 is delivered to the lifting pins 60 that have been raised and waiting in advance. Thereafter, the lift pins 60 are lowered and the temperature inspection jig 10 is placed on the heat treatment plate 50. At this time, the hot plate regions R _{1 to} R ₄ of the heat treatment plate 50 are adjusted to an initial temperature predetermined by the control unit 100. Thereafter, the lid member 30 is lowered to a predetermined position, and the lid member 30 is closed. Then, heat treatment is performed on the wafer 70 to be processed of the temperature inspection jig 10 placed on the heat treatment plate 50 for a predetermined time.

On the other hand, the contact 41 is in contact with the contact pad 72 of the temperature inspection jig 10 placed on the heat treatment plate 50. At this time, since the contact pads 72 are continuously arranged along the peripheral edge of the wafer 70 to be processed, the wafer 70 to be processed is placed on the heat treatment plate 50 in a state of being rotated in a horizontal plane from a predetermined position. Even so, the contact 41 securely contacts the contact pad 72. It is desirable that the gap between the contact pads 72 be so small that the possibility that the contact 41 contacts the gap is negligible. Then, after the heat treatment on the processing target wafer 70 is completed, the measurement result of the resistance value of the resistance temperature detector 71 is output from the contact pad 72 to the control unit 100 via the contact 41. Next, the control unit 100 measures the temperature of the processing target wafer 70 based on the measured resistance value of the resistance temperature detector 71. At this time, the in-plane distribution of the temperature of the processing target wafer 70 may be visualized. Then, based on the measured temperature of the wafer 70 to be processed, the temperature of the heat treatment plate 50 is adjusted so that the temperature of the wafer 70 to be processed becomes a predetermined temperature. At this time, the control unit 100 adjusts the temperature of the thermal processing plate 50 for each of the thermal plate regions _R 1 to R _4.

  When the temperature of the heat treatment plate 50 is adjusted as described above, the elevating pin 60 is raised and the temperature inspection jig 10 is carried out of the heat treatment apparatus 2. Thus, the temperature of the heat treatment plate 50 is adjusted.

  If the resistance values of all the temperature measuring resistors 71 (the temperature of the wafer 70 to be processed) cannot be set to a predetermined value by one temperature adjustment, the temperature adjustment is performed a plurality of times. That is, the heat treatment of the processing target wafer 70, the measurement of the resistance value of the resistance temperature detector 71, and the temperature adjustment of the heat processing plate 50 are repeatedly performed, and the processing target wafer 70 is uniformly heat-treated at a predetermined temperature.

  According to the above embodiment, since the contact pads 72 are continuously arranged along the peripheral edge of the wafer 70 to be processed, the heat treatment plate is rotated in a state where the wafer 70 to be processed is rotated in a horizontal plane from a predetermined position. Even when placed on the contact 50, the contact 41 reliably contacts the contact pad 72. For this reason, the resistance value of the resistance temperature detector 71 can be reliably measured, and the temperature of the processing target wafer 70 on the heat treatment plate 50 can be appropriately measured. Therefore, the temperature of the heat treatment plate 50 can be appropriately adjusted based on the measured temperature of the processing target wafer 70. Then, the subsequent heat treatment of the wafer W can be appropriately performed by the heat treatment plate 50 whose temperature is adjusted in this way.

  In addition, since the resistance temperature detector 71 and the contact pad 72 are spaced apart from each other by a predetermined distance D in the horizontal direction, when the contact 41 is brought into contact with the contact pad 72, the contact 41 is contacted. The resistance temperature detector 71 is not affected by the temperature change. Therefore, the resistance value of the resistance temperature detector 71 can be accurately measured.

Furthermore, the heating plate 50 is partitioned into a plurality of thermal plate regions _R 1 to R _4, the heater 53 individually to each of the thermal plate regions _R 1 to R ₄ are built. For this reason, the temperature can be adjusted for each of the hot plate regions R _{1 to} R _4, and the temperature of the heat treatment plate 50 can be adjusted more strictly.

  In the above embodiment, two contact pads 72 are connected to one resistance temperature detector 71 and the resistance value of the resistance temperature detector 71 is measured by a so-called two-wire connection type. A 4-wire connection type may be used instead of the formula. In such a case, four contact pads 72 are connected to one resistance temperature detector 71. When the four-wire connection type is used, the resistance value of the resistance temperature detector 71 can be measured more accurately.

  In the above-described embodiment, as shown in FIG. 5, one of the plurality of temperature measuring resistors 71 may be one temperature measuring resistor as the reference resistor 110. The reference resistor 110 has a resistance value that does not change in response to a temperature change and is dissociated from the resistance value of the resistance temperature detector 71 by a predetermined amount or more, for example, 300Ω or more. Even if the resistance value of the reference resistor 110 changes according to the temperature change, it is only necessary that the change band of the resistance value is different or the change width is small enough to be distinguished from the other resistance temperature detectors 71. In addition, two reference contact pads 111 are electrically connected to the reference resistor 110 via wirings 112. The contact 41 contacts the reference contact pad 111 when the temperature of the heat treatment plate 50 is adjusted. The reference contact pad 111 and the wiring 112 are made of a conductive material such as aluminum. The plurality of contact pads 72 and the plurality of reference contact pads 111 are continuously arranged along the peripheral edge of the wafer 70 to be processed.

In this case, the resistance value of the reference resistor 110 does not change according to the temperature change and has a resistance value dissociated from the resistance value of the resistance temperature detector 71 by a predetermined amount or more. The resistance value of the resistance temperature detector 71 and the resistance value of the reference resistor 110 measured during the heat treatment can be distinguished. As a result, the control unit 100 can grasp the position of the reference resistor 110 with respect to the heat treatment plate 50, so that the position of the other resistance temperature detector 71 can be grasped, and the wafer to be processed on the heat treatment plate 50. The position of 70 in the horizontal plane can also be grasped. That is, the positions of the reference resistor 110 and the resistance temperature detector 71 can be associated with the hot plate regions R _{1 to} R ₄ of the heat treatment plate 50. Therefore, according to the present embodiment, the temperature adjustment of the heat treatment plate 50 can be appropriately performed for each of the hot plate regions R _{1 to} R ₄ .

  In the temperature inspection jig 10 of the above embodiment, the Wheatstone bridge circuit 120 may be formed on the processing target wafer 70 as shown in FIG. Each Wheatstone bridge circuit 120 has the four resistance temperature detectors 71 described above. A metal pad 121 is disposed at the apex of the Wheatstone bridge circuit 120. The resistance temperature detector 71 and the metal pad 121 are connected by a wiring 122. The metal pad 121 and the contact pad 72 are connected by a wiring 123. The contact pads 72 are continuously arranged along the peripheral edge of the processing target wafer 70 as in the above embodiment. The metal pad 121 and the wirings 122 and 123 are made of a conductive material such as aluminum. In this embodiment, since the contact 41 does not contact the metal pad 110, the metal pad 110 may be omitted and the wiring 122 and the wiring 123 may be directly connected.

  As shown in FIG. 7, in the Wheatstone bridge circuit 120, the pair of metal pads 121 a and 121 a provided at both ends of the two resistance temperature detectors 71 and 71 in series, that is, the contact pads 72 a and 72 a are connected to the Wheatstone bridge circuit 120. Is used to apply a voltage. A pair of metal pads 121b and 121b provided at the midpoint between the two resistance temperature detectors 71 and 72 in series, that is, the contact pads 72b and 72b are for measuring the voltage between the contact pads 72b and 72b. Used. That is, the contact pads 72 b and 72 b are used for measuring the offset voltage in the Wheatstone bridge circuit 120. Note that the arrows in FIG. 7 indicate the current when a voltage is applied to the Wheatstone bridge circuit 71.

In such a case, a predetermined voltage is applied to the contact pads 72 a and 72 a on the processing target wafer 70 via the contact 41 with respect to the processing target wafer 70 after the heat treatment. Subsequently, a measurement result signal is output from the contact pads 72 b and 72 b to the control unit 100 via the contact 41. In this way, the control unit 100 measures the offset voltage of the Wheatstone bridge circuit 120 (the voltage between the contact pads 72b and 72b). And in the control part 100, the temperature of the heat processing board 50 is adjusted so that the offset voltage of the some Wheatstone bridge circuit 120 may become zero. That is, the control unit 100 adjusts the temperature of the heat treatment plate 50 for each of the hot plate regions R _{1 to} R ₄ so that the offset voltage of the plurality of Wheatstone bridge circuits 120 becomes zero.

  Note that the offset voltage of the Wheatstone bridge circuit 120 being zero means that the resistance values of the four resistance temperature detectors 71 in the Wheatstone bridge circuit 120 are equal. That is, the temperature of the processing target wafer 70 provided with the Wheatstone bridge circuit 120 becomes uniform. Therefore, when the offset voltage of all Wheatstone bridge circuits 120 becomes zero, the temperature becomes uniform throughout the wafer 70 to be processed.

  According to the present embodiment, the temperature of the heat treatment plate 50 is set so that the Wheatstone bridge circuit 120 formed on the processing target wafer 70 is in an equilibrium state, that is, the offset voltage in the Wheatstone bridge circuit 120 is zero. Is adjusted. In this case, since the offset voltage becomes zero, the resistance values of the four resistance temperature detectors 71 in the Wheatstone bridge circuit 120, that is, the temperatures of the processing target wafers 70 measured by these resistance temperature detectors 71 become equal. In addition, since the offset voltage in all the Wheatstone bridge circuits 120 on the processing target wafer 70 becomes zero, the temperatures of the processing target wafers 70 in these Wheatstone bridge circuits 120 become equal. Therefore, according to the present embodiment, the temperature of the heat treatment plate 50 can be appropriately adjusted so that the wafer 70 to be processed is heat-treated uniformly in a horizontal plane. In other words, this embodiment is particularly useful when the temperature of the heat treatment plate 50 is adjusted, as long as the in-plane uniformity of the temperature of the wafer 70 to be processed can be secured, and absolute temperature adjustment is unnecessary. The set output of the heat treatment plate 50 is inherently worthy of trust, but it is common in actual sites that individuals whose output values vary with the passage of time. In such a case, it can be considered that the temperature is sufficiently adjusted when the in-plane uniformity is ensured.

  Further, since the Wheatstone bridge circuit 120 includes the four resistance temperature detectors 71, the temperature at four locations is measured using the conventional method. Then, the temperature of the heat treatment plate 50 is adjusted using these four parameters. On the other hand, according to the present embodiment, the parameter used for adjusting the temperature of the heat treatment temperature 50 is only one of the offset voltages of the Wheatstone bridge circuit 120. Thus, according to the present embodiment, since the number of parameters is small, the temperature of the heat treatment plate 50 can be adjusted with simple control. Therefore, the load applied to the heater 53 of the heat treatment plate 50 can be reduced, and the temperature of the heat treatment plate 50 can be adjusted in a short time.

  Furthermore, in the above embodiment, two contact pads 72 (two wirings 73) are provided for one resistance temperature detector 71. On the other hand, in the Wheatstone bridge circuit 120, four contact pads 72 (four wires 122) are provided for the four resistance temperature detectors 71. Therefore, when the Wheatstone bridge circuit 120 is used as in the present embodiment, the number of contact pads 72 and the number of wirings can be reduced.

  In the above embodiment, the offset voltage in the Wheatstone bridge circuit 120 is used as a parameter for adjusting the temperature of the heat treatment plate 50. However, in addition to this offset voltage, the current value in the Wheatstone bridge circuit 120 may be used. Good.

  In this case, in the heat treatment apparatus 2, after the heat treatment is performed on the temperature inspection jig 10 placed on the heat treatment plate 50, in addition to the offset voltage of the Wheatstone bridge circuit 120 in the temperature inspection jig 10, the Wheatstone bridge The current value of the circuit 120 is measured. In the control unit 100, the offset voltage of all the Wheatstone bridge circuits 120 becomes zero, the current value of the Wheatstone bridge 71 becomes a predetermined value, and the current values of all the Wheatstone bridge circuits 120 become equal. The temperature of the heat treatment plate 50 is adjusted.

  According to the present embodiment, the resistance values of the resistance temperature detectors 71 in all the Wheatstone bridge circuits 120 on the processing target wafer 70 can be made equal to a predetermined value. Therefore, the temperature of the heat treatment plate 50 can be adjusted so that the wafer 70 to be processed is uniformly heat-treated at a predetermined temperature. Even in such a case, there are two parameters for adjusting the temperature of the heat treatment temperature 50, that is, the offset voltage and the current value of the Wheatstone bridge circuit 120. Therefore, the temperature of the heat treatment plate 50 can be adjusted with simpler control than before. Can do.

  In the above embodiment, the control unit 100 may record a table (not shown) indicating the relationship between the current value in the Wheatstone bridge circuit 120 and the temperature of the processing target wafer 70, for example. In such a case, the control unit 100 measures the temperature of the processing target wafer 70 using the above table based on the measured current value of the Wheatstone bridge circuit 120. Thereby, the absolute temperature of the to-be-processed wafer 70 after heat processing can be grasped | ascertained.

  In the above embodiment, as shown in FIG. 8, one Wheatstone bridge circuit among the plurality of Wheatstone bridge circuits 120 may be used as the reference Wheatstone bridge circuit 130. The reference Wheatstone bridge circuit 130 includes the four reference resistors 110 instead of the four resistance temperature detectors 71. The reference Wheatstone bridge circuit 120 has the four reference contact pads 111 instead of the four contact pads 72. The plurality of contact pads 72 and the reference contact pad 111 are continuously arranged along the peripheral edge of the wafer 70 to be processed. Since the other configuration of the reference Wheatstone bridge circuit 120 is the same as the configuration of the Wheatstone bridge circuit 71 in the above embodiment, the description thereof is omitted.

As described above, since the resistance value of the reference resistor 110 does not change according to the temperature change and has a resistance value dissociated from the resistance value of the resistance temperature detector 71 by a predetermined amount or more, it is shown in FIG. Similarly to the above embodiment, the control unit 100 can grasp the position of the reference resistor 110 with respect to the heat treatment plate 50, the positions of the reference resistor 110 and the resistance temperature detector 71, and the heat of the heat treatment plate 50. The plate regions R _{1 to} R ₄ can be associated with each other. Therefore, according to the present embodiment, the temperature adjustment of the heat treatment plate 50 can be appropriately performed for each of the hot plate regions R _{1 to} R ₄ .

  In the above embodiment, a plurality of Wheatstone bridge circuits 120 are provided on the wafer 70 to be processed. However, for example, as shown in FIG. 9, a circuit 140 in which these Wheatstone bridge circuits 120 are integrated may be formed. Good. The circuit 140 has a configuration in which a plurality of resistance temperature detectors 71 and a plurality of metal pads 121 are arranged in a grid pattern. That is, in the circuit 140, the plurality of resistance temperature detectors 71 are arranged in parallel. In such a case, the pair of metal pads 121 a and 121 a at the apex of the circuit 140, that is, the contact pads 72 a and 72 a are used to apply a voltage to the circuit 140.

  In such a case, a predetermined voltage is applied to the contact pads 72 a and 72 a on the processing target wafer 70 via the contact 41 with respect to the processing target wafer 70 after the heat treatment. Subsequently, a measurement result signal is output from the other contact pad 72 to the control unit 100 via the contact 41. In this way, the control unit 100 can measure the resistance value of each resistance temperature detector 71 and can adjust the temperature of the heat treatment plate 50 based on the measured resistance value.

  Further, as compared to the case where two contact pads 72 (two wirings 73) are provided for one resistance temperature detector 71 as in the above embodiment, the number of contact pads 72 and the number of wirings are increased. Can be reduced.

  In the above embodiment, the plurality of resistance temperature detectors 71 are arranged in parallel in the circuit 140, but they may be arranged in series. Even in such a case, the temperature of the heat treatment plate 50 can be adjusted, and the number of contact pads 72 and the number of wirings can be reduced.

  In the temperature inspection jig 10 of the above embodiment, as shown in FIG. 10, the contact pad 72 is supported by the support member 150 and is perpendicular to the surface of the wafer 70 to be processed by a predetermined distance H, for example, 500 μm. They may be spaced apart. For the support member 150, for example, a flexible cable, a rigid substrate, or the like is used. In such a case, when the contact 41 comes into contact with the contact pad 72, the temperature measuring resistor 71 is not affected by the temperature change due to the contact of the contact 41. That is, in the present embodiment, the temperature of the processing target wafer 70 provided with the temperature measuring resistor 71 is not lowered by the contact of the contact 41. Therefore, the resistance value of the resistance temperature detector 71 can be accurately measured. In such a case, after the temperature of the heat treatment plate 50 is adjusted, when the product wafer W is placed on the heat treatment plate 50 for heat treatment in the heat treatment apparatus 2, the tip of the contact 41 is positioned at the wafer 70 to be processed. Does not reach the surface. Therefore, the contact 41 does not come into contact with the wafer W, and damage of the wafer W can be avoided.

  In the temperature inspection jig 10 of the above embodiment, the heat insulating layer 160 may be formed on the surface of the wafer 70 to be processed and directly below the contact pad 72 as shown in FIG. As the heat insulating layer 160, for example, a porous heat insulating layer such as a nano silicon (nc-Si) layer is used. In such a case, when the contact 41 is brought into contact with the contact pad 72, the temperature measuring resistor 71 due to the contact of the contact 41 can reliably prevent the temperature change from being caused by the heat insulating layer 160. Therefore, the resistance value of the resistance temperature detector 71 can be accurately measured.

In the above embodiment, thermal processing plate 50, which had been divided into four thermal plate regions R ₁ to R _4, the number can be arbitrarily selected. The shape of the thermal plate regions _R 1 to R ₄ of the thermal processing plate 50 is also arbitrarily selected.

  In addition, the heat treatment performed in the heat treatment apparatus 2 of the above embodiment may be, for example, a heat treatment in a photolithography process or a heat treatment in a plasma process such as an etching process or a film forming process. In this case, the heat transferred to the wafer W is not limited to the heat from the heat treatment plate 50 but includes heat transfer from an etching gas or plasma.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the idea described in the claims, and these naturally belong to the technical scope of the present invention. It is understood. The present invention is not limited to this example and can take various forms. The present invention can also be applied to a case where the substrate is another substrate such as an FPD (flat panel display) other than a wafer or a mask reticle for a photomask.

DESCRIPTION OF SYMBOLS 1 Temperature calibration apparatus 2 Heat processing apparatus 10 Temperature test | inspection jig 30 Lid member 41 Contact 50 Heat processing board 70 Processed wafer 71 Resistance thermometer 72 Contact pad 100 Control part 110 Reference resistor 111 Reference contact pad 120 Wheatstone bridge circuit 130 Reference Wheatstone bridge circuit 160 insulation layer R ₁ to R ₄ of the thermal plate regions W wafer

Claims (22)

A temperature calibration device for calibrating the temperature of the heat treatment mechanism with respect to a heat treatment device that heats the substrate to a predetermined temperature using a heat treatment mechanism,
A substrate,
A plurality of resistance thermometers provided on the substrate, the resistance value of which varies according to a temperature change;
A plurality of contact pads provided on the substrate, electrically connected to the resistance temperature detector, and contacted by a contact when measuring the temperature of the substrate;
A controller that measures the temperature of the substrate based on the resistance value of the resistance temperature detector measured through the contact pad and the contact;
The temperature calibration device, wherein the plurality of contact pads are continuously arranged along a peripheral edge of the substrate. A reference resistor provided on the substrate, the resistance value does not change according to a temperature change, and has a resistance value dissociated by a predetermined amount or more from the resistance value of the resistance temperature detector;
A plurality of reference contact pads provided on the substrate, electrically connected to the reference resistor, and contacted by a contact when measuring the temperature of the substrate;
The temperature calibration apparatus according to claim 1, wherein the plurality of contact pads and the plurality of reference contact pads are continuously arranged along a peripheral portion of the substrate. 3. The temperature calibration apparatus according to claim 1, wherein the control unit adjusts a temperature of the heat treatment mechanism based on the measured temperature of the substrate. A Wheatstone bridge circuit is formed by the plurality of resistance thermometers,
4. The temperature calibration apparatus according to claim 3, wherein the control unit adjusts the temperature of the heat treatment mechanism so that the Wheatstone bridge circuit is in an equilibrium state. 5. The temperature calibration apparatus according to claim 4, wherein the controller adjusts the temperature of the heat treatment mechanism so that a current value in the Wheatstone bridge circuit becomes a predetermined value. A plurality of the Wheatstone bridge circuits are formed,
6. The temperature calibration apparatus according to claim 4, wherein the controller adjusts the temperature of the heat treatment mechanism so that current values in the plurality of Wheatstone bridge circuits are equal. The temperature calibration device according to claim 3, wherein the heat treatment mechanism is divided into a plurality of regions, and the temperature can be adjusted for each region. The temperature calibration device according to any one of claims 1 to 7, wherein the resistance temperature detector and the contact pad are arranged at a predetermined distance in the horizontal direction. The temperature calibration apparatus according to claim 1, wherein the contact pad is disposed at a predetermined distance from the surface of the substrate in the vertical direction. The temperature calibration apparatus according to claim 1, wherein a heat insulating layer is formed on the surface of the substrate and immediately below the contact pad. The heat treatment apparatus has a lid member provided so as to be movable up and down above the heat treatment mechanism,
The contact is disposed on the lower surface of the lid member so as to face the contact pad,
The temperature calibration device according to claim 1, wherein the contact pad comes into contact with the contact when the lid member is lowered to a predetermined position. A temperature calibration method for calibrating the temperature of the heat treatment mechanism using a temperature calibration device with respect to a heat treatment device for heat treating the substrate to a predetermined temperature using the heat treatment mechanism,
A substrate,
A plurality of resistance thermometers provided on the substrate, the resistance value of which varies according to a temperature change;
A plurality of contact pads arranged continuously along a peripheral edge on the substrate, electrically connected to the resistance temperature detector, and contacted by a contact when measuring the temperature of the substrate; Using a temperature calibration device,
A first step of bringing the contact into contact with a contact pad on a substrate placed on the heat treatment mechanism, and measuring a resistance value of the resistance temperature detector through the contact pad and the contact;
And a second step of measuring the temperature of the substrate based on the measured resistance value of the resistance temperature detector. The temperature calibration device is provided on the substrate, the resistance value does not change according to a temperature change, and the reference resistor has a resistance value dissociated by a predetermined amount or more from the resistance value of the resistance temperature detector, A plurality of reference contact pads provided on a substrate, electrically connected to the reference resistor, and contacted by a contact when measuring the temperature of the substrate;
The plurality of contact pads and the plurality of reference contact pads are continuously disposed along a peripheral edge of the substrate,
The said 1st process WHEREIN: The said contactor is made to contact the said reference contact pad, The resistance value of the said reference resistor is measured via the said reference contact pad and a contactor, It is characterized by the above-mentioned. Temperature calibration method. 14. The temperature calibration method according to claim 12, further comprising a third step of adjusting the temperature of the heat treatment mechanism based on the measured temperature of the substrate. A Wheatstone bridge circuit is formed by the plurality of resistance thermometers,
15. The temperature calibration method according to claim 14, wherein, in the third step, the temperature of the heat treatment mechanism is adjusted so that the Wheatstone bridge circuit is in an equilibrium state. 16. The temperature calibration method according to claim 15, wherein in the third step, the temperature of the heat treatment mechanism is adjusted so that a current value in the Wheatstone bridge circuit becomes a predetermined value. A plurality of the Wheatstone bridge circuits are formed,
The temperature calibration method according to claim 15 or 16, wherein, in the third step, the temperature of the heat treatment mechanism is adjusted so that current values in the plurality of Wheatstone bridge circuits are equal. The heat treatment mechanism is partitioned into a plurality of regions, and the temperature can be adjusted for each region,
The temperature calibration method according to any one of claims 14 to 17, wherein in the third step, the temperature of the heat treatment mechanism is adjusted for each region. The temperature calibration method according to any one of claims 12 to 18, wherein the resistance temperature detector and the contact pad are spaced apart from each other by a predetermined distance in the horizontal direction. The temperature calibration method according to any one of claims 12 to 19, wherein the contact pads are arranged at a predetermined distance from the surface of the substrate in the vertical direction. The temperature calibration method according to any one of claims 12 to 20, wherein a heat insulating layer is formed on the surface of the substrate and immediately below the contact pad. The heat treatment apparatus has a lid member provided so as to be movable up and down above the heat treatment mechanism,
The contact is disposed on the lower surface of the lid member so as to face the contact pad,
The temperature calibration method according to any one of claims 12 to 21, wherein, in the first step, the contact pad comes into contact with the contact when the lid member is lowered to a predetermined position.

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