KR20160036654A - Substrate heat processing apparatus, substrate heat processing method, storage medium and heat processing status detecting apparatus - Google Patents

Abstract

An object of the present invention is to provide a substrate heat treatment apparatus, a substrate heat treatment method and a recording medium which can more reliably detect an abnormality in a heat treatment state. The heat treatment unit U2 includes a heat plate 20 for mounting the wafer W, a heater 21 for heating the wafer W on the mounting portion, A plurality of temperature sensors 40 arranged to respectively correspond to the temperature sensor 40 and the control unit 100, respectively. The control unit 100 controls the heater 21 based on the temperatures detected by the plurality of temperature sensors 40 and controls the temperature detected by the plurality of temperature sensors 40 to the center The position of the center of the temperature is calculated, and the heat treatment state of the wafer W is detected based on the position of the center of temperature.

Description

TECHNICAL FIELD [0001] The present invention relates to a substrate heat treatment apparatus, a substrate heat treatment method, a recording medium, and a heat treatment state detecting apparatus. BACKGROUND OF THE INVENTION [0001]

The present disclosure relates to a substrate heat treatment apparatus, a substrate heat treatment method, a recording medium, and a heat treatment state detection apparatus.

When a semiconductor device is manufactured, the wafer is heat-treated in various processes. In the heat treatment, it is required to reliably heat each part of the wafer. Patent Document 1 discloses a heat treatment apparatus provided with an abnormality detecting means that an abnormality occurs when the integrated value of the difference between the surface temperature of the heat treatment plate and the set temperature of the heat treatment plate is equal to or lower than a predetermined threshold value.

Japanese Patent Application Laid-Open No. 2009-123816

In the above-described heat treatment apparatus, there is a possibility that an abnormality that partially occurs can not be detected. It is an object of the present invention to provide an apparatus, a method, and a recording medium capable of more reliably detecting an abnormality in a heat treatment state.

A substrate heat treatment apparatus according to the present disclosure includes a stacking portion for stacking a substrate, a heat treatment portion for heating or cooling the substrate on the stacking portion, a plurality of temperature sensors arranged corresponding to a plurality of portions of the substrate on the stacking portion, , Controlling the heat treatment section based on the temperatures detected by the plurality of temperature sensors, calculating the position of the temperature center corresponding to the center of gravity when the temperature detected by the plurality of temperature sensors is regarded as mass And a control unit configured to detect the heat treatment state of the substrate based on the position of the temperature center.

According to this substrate heat treatment apparatus, the heat treatment state of the substrate is detected based on the position of the temperature center. The position of the temperature center fluctuates with high sensitivity depending on the partial abnormality in the heat treatment state. Therefore, the partial abnormality of the heat treatment state can be detected with high sensitivity based on the position of the center of temperature. Therefore, it is possible to more reliably detect an abnormality in the heat treatment state.

The control unit calculates the position of the temperature center in the plane parallel to the substrate as the first center position and calculates the position of the temperature center in the radial direction orthogonal to the center of the substrate as the second center position, And the heat treatment state of the substrate may be detected based on the second central position. The first central position fluctuates with high sensitivity depending on the partial abnormality in the heat treatment state, but it is hard to fluctuate as long as the temperature distribution becomes point symmetry with respect to the center of the substrate. As a specific example of such a case, when the central portion of the substrate floats from the stacking portion, the entire peripheral portion of the substrate floats uniformly from the stacking portion. On the other hand, the second central position fluctuates in accordance with the temperature distribution along the radial direction of the substrate, so that even when the temperature distribution becomes point symmetry with respect to the center of the substrate, the second central position fluctuates with high sensitivity. Therefore, by detecting the heat treatment state of the substrate based on both the first and second center positions, it is possible to more reliably detect an abnormality in the heat treatment state.

The control unit may calculate the second center position by considering the average value of the temperatures detected by the plurality of temperature sensors at positions equivalent to each other in the radial direction as the mass of the position. The control unit may calculate the second center position by considering the average value of the temperatures detected by the temperature sensor in each of the plurality of regions arranged concentrically with the substrate in the radial direction as the mass of the region. In these cases, the second center position can be calculated with higher accuracy.

The control unit may be configured to detect the heat treatment state of the substrate on the basis of the difference between the position of the center of temperature and the reference position using a predetermined reference position based on the position of the center of temperature when the substrate is normally heat treated . In this case, the heat treatment state of the substrate is detected on the basis of the component separated from the reference position among the positions of the temperature center. Based on the components separated from the reference position, the criterion for determining whether the heat treatment state is normal or abnormal can be simplified.

The control unit uses the average value of the position of the center of temperature calculated in the normal heat treatment a plurality of times as the reference position and sets the allowable range determined based on the standard deviation of the position of the center of temperature calculated in the normal heat treatment a plurality of times And when the difference between the position of the center of temperature and the reference position is outside the permissible range, it may be configured to detect that the heat treatment state of the substrate is abnormal. In this case, an abnormality in the heat treatment state can be detected by a simple criterion of whether or not the position of the center of temperature is within an allowable range. By using the average value as the reference position and using the allowable range determined based on the standard deviation, it is possible to allow an appropriate deviation and to reduce unnecessary abnormality detection.

The control unit may be configured to further execute the output of information on the position of the temperature center. Based on the position of the temperature center, it is also possible to grasp in which direction the abnormality of the heat treatment state occurred. Thus, by outputting information about the position of the center of temperature, it is possible to provide information useful for specifying the position of the cause of the abnormality in the heat treatment state.

The control unit may be configured to also output the locus information of the difference between the position of the center of temperature and the reference position. In this case, out of the positions of the temperature center, the locus information of the components separated from the reference position is output. According to the locus information of the components separated from the reference position, it is possible to more easily grasp in which direction the temperature abnormality occurs. Therefore, it is possible to provide information that is more beneficial for specifying a position as a cause of abnormality in the heat treatment state.

Wherein the heat treatment section is controllable for each of a plurality of treatment areas arranged along the substrate and the control section specifies the treatment area in which the heat treatment is insufficient based on the position of the center of temperature and the heat treatment section for promoting the heat treatment of the treatment area And may also be configured to execute control. In this case, the reliability of the heat treatment can be improved by performing the heat treatment according to the positional information of the temperature center.

The control unit may be configured to calculate the position of the center of temperature by equations (1) and (2).

X, Y: Position of center of temperature in Cartesian coordinate system

xi, yi: the position of the temperature sensor in the Cartesian coordinate system

Ti: temperature detected by the temperature sensor

n: Number of temperature sensors

The temperature is detected by a plurality of temperature sensors arranged corresponding to a plurality of portions of the substrate on the mounting portion, Controlling the heat treatment section based on the temperatures detected by the plurality of temperature sensors, calculating the position of the temperature center corresponding to the center when the temperature detected by the plurality of temperature sensors is regarded as the mass, And detecting the heat treatment state of the substrate based on the position of the substrate.

According to this substrate heat treatment method, the heat treatment state of the substrate is detected based on the position of the temperature center. The position of the temperature center fluctuates with high sensitivity depending on the partial abnormality in the heat treatment state. Therefore, the partial abnormality of the heat treatment state can be detected with high sensitivity based on the position of the center of temperature. Therefore, it is possible to more reliably detect an abnormality in the heat treatment state.

The position of the temperature center in the plane parallel to the substrate is calculated as the first center position and the position of the temperature center in the radial direction perpendicular to the center of the substrate is calculated as the second center position, The heat treatment state of the substrate may be detected based on the center position. The first central position fluctuates with high sensitivity depending on the partial abnormality in the heat treatment state, but it is hard to fluctuate as long as the temperature distribution becomes point symmetry with respect to the center of the substrate. As a specific example of such a case, when the central portion of the substrate floats from the stacking portion, the entire peripheral portion of the substrate floats uniformly from the stacking portion. On the other hand, the second central position fluctuates in accordance with the temperature distribution along the radial direction of the substrate, so that even when the temperature distribution becomes point symmetry with respect to the center of the substrate, the second central position fluctuates with high sensitivity. Therefore, by detecting the heat treatment state of the substrate based on both the first and second center positions, it is possible to more reliably detect an abnormality in the heat treatment state.

The second center position may be calculated by considering the average value of the temperatures detected by the plurality of temperature sensors located at equal positions in the radial direction as the mass of the position. The average value of the temperatures detected by the temperature sensor in each of the plurality of regions arranged concentrically with the substrate in the radial direction may be regarded as the mass of the region to calculate the second center position. In these cases, the second center position can be calculated with higher accuracy.

The predetermined reference position may be used based on the position of the center of temperature when the substrate is normally heat treated and the heat treatment state of the substrate may be detected based on the difference between the position of the center of temperature and the reference position. In this case, the heat treatment state of the substrate is detected on the basis of the component separated from the reference position among the positions of the temperature center. Based on the components separated from the reference position, the criterion for determining whether the heat treatment state is normal or abnormal can be simplified.

An average value of positions of temperature centers calculated in a plurality of normal heat treatments is used as a reference position and an allowable range determined based on a standard deviation of positions of temperature centers calculated in a plurality of normal heat treatments is also used, It may be detected that the heat treatment state of the substrate is abnormal when the difference between the position of the center of temperature and the reference position is outside the permissible range. In this case, an abnormality in the heat treatment state can be detected by a simple criterion of whether or not the position of the center of temperature is within an allowable range. In addition, by using the average value as the reference position and using the allowable range determined based on the standard deviation, an appropriate deviation can be allowed, thereby reducing unnecessary abnormality detection.

And outputting information on the position of the temperature center. Based on the position of the temperature center, it is also possible to grasp in which direction the abnormality of the heat treatment state occurred. Thus, by outputting information about the position of the center of temperature, it is possible to provide information useful for specifying the position of the cause of the abnormality in the heat treatment state.

And outputting the locus information of the difference between the position of the temperature center and the reference position. In this case, out of the positions of the temperature center, the locus information of the components separated from the reference position is output. According to the locus information of the components separated from the reference position, it is possible to more easily grasp in which direction the temperature abnormality occurs. Therefore, it is possible to provide more useful information for specifying a position as an abnormal factor of the heat treatment state.

Specifying a processing region where the heat treatment is insufficient based on the position of the center of temperature, and promoting the heat treatment of the processing region. In this case, the reliability of the heat treatment can be improved by performing the heat treatment according to the positional information of the temperature center.

The position of the center of temperature may be calculated by the above-mentioned equations (1) and (2).

The recording medium according to the present disclosure is a computer-readable recording medium on which a program for causing the apparatus to perform the substrate heat treatment method is recorded.

The heat treatment state detecting apparatus according to the present disclosure is characterized by comprising: obtaining a temperature detected by a plurality of temperature sensors arranged so as to respectively correspond to a plurality of locations on a substrate to be subjected to a heat treatment on a mounting section; The position of the center of the temperature corresponding to the center of the case is calculated and the heat treatment state of the substrate is detected based on the position of the temperature center.

According to the present disclosure, an abnormality in the heat treatment state can be more reliably detected.

1 is a perspective view of a coating / developing system;
2 is a sectional view taken along line II-II in Fig. 1; Fig.
3 is a sectional view taken along line III-III in Fig. 2; Fig.
4 is a schematic diagram of a heat treatment unit.
5 is a plan view of a heating plate.
6 is a flow chart of the heat treatment process of the wafer by the heat treatment unit.
7 is a graph illustrating a change in temperature over time during heat treatment.
8 is a graph illustrating the locus of the first center position during the heat treatment.
9 is a graph exemplifying the locus of the second center position during the heat treatment;
10 is a graph exemplifying the locus of the difference between the position of the center of temperature and the reference position during heating;
11 is a flowchart showing a modified example of the heat treatment procedure.

Hereinafter, embodiments will be described in detail with reference to the drawings. In the description, the same elements or elements having the same function are denoted by the same reference numerals, and redundant explanations are omitted.

[Substrate processing system]

First, the outline of the substrate processing system 1 according to the present embodiment will be described. The substrate processing system 1 includes a coating and developing apparatus 2 and an exposure apparatus 3. [ The exposure apparatus 3 performs exposure processing of a resist film (photosensitive film). Specifically, an energy line is irradiated to a part to be exposed of the resist film by a method such as immersion exposure. The coating and developing apparatus 2 performs a process of forming a resist film on the surface of the wafer W (substrate) before the exposure process by the exposure apparatus 3, and performs a developing process of the resist film after the exposure process.

1 and 2, the coating and developing apparatus 2 includes a carrier block 4, a processing block 5, and an interface block 6. As shown in Fig. The carrier block 4, the processing block 5, and the interface block 6 are arranged in the horizontal direction.

The carrier block 4 has a carrier station 12 and a carry-in / carry-out section 13. The loading / unloading section 13 is interposed between the carrier station 12 and the processing block 5. [ The carrier station 12 supports a plurality of carriers 11. The carrier 11 accommodates a plurality of circular wafers W in a sealed state, for example, and has an opening / closing door on the side of one side 11a for allowing the wafer W to enter and exit. The carrier 11 is detachably mounted on the carrier station 12 such that the side surface 11a faces the loading / unloading portion 13 side.

The loading / unloading section 13 has a plurality of opening / closing doors 13a corresponding to the plurality of carriers 11 on the carrier station 12. [ The opening and closing door of the side face 11a and the opening and closing door 13a are simultaneously opened so that the inside of the carrier 11 and the carry-in / carry-out section 13 communicate with each other. The loading / unloading section 13 incorporates a receiving arm A1. The transfer arm A1 takes out the wafer W from the carrier 11 and transfers it to the processing block 5 to receive the wafer W from the processing block 5 and return it to the carrier 11. [

The processing block 5 has a plurality of processing modules 14, 15, 16 and 17. 2 and 3, the processing modules 14, 15, 16 and 17 include a plurality of liquid processing units U1, a plurality of heat processing units U2, (Not shown). The processing module 17 also incorporates a direct transfer arm A6 for transferring the wafer W without passing through the liquid processing unit U1 and the heat treatment unit U2. The liquid processing unit (U1) applies liquid to the surface of the wafer (W). The heat treatment unit U2 heats the wafer W by, for example, a hot plate, and performs the heat treatment by cooling the heated wafer W by, for example, a cooling plate.

The processing module 14 is a BCT module for forming a lower layer film on the surface of the wafer W by a liquid processing unit U1 and a heat treatment unit U2. The liquid processing unit (U1) of the processing module (14) applies the liquid for forming the lower layer film onto the wafer (W). The heat treatment unit (U2) of the treatment module (14) performs various heat treatments accompanying the formation of the lower layer film. As a specific example of the heat treatment, there can be mentioned a heat treatment for curing the liquid for forming the lower layer film.

The processing module 15 is a COT module for forming a resist film on a lower layer film by a liquid processing unit U1 and a heat treatment unit U2. The liquid processing unit (U1) of the processing module (15) applies a liquid for forming a resist film onto the lower layer film. The heat treatment unit (U2) of the treatment module (15) performs various heat treatments accompanying the formation of the resist film. Specific examples of the heat treatment include a heat treatment for curing a liquid for forming a resist film.

The processing module 16 is a TCT module for forming a lower layer film on a resist film by a liquid processing unit U1 and a heat treatment unit U2. The liquid processing unit (U1) of the processing module (16) applies the liquid for forming the upper layer film onto the resist film. The heat treatment unit (U2) of the treatment module (16) performs various heat treatments accompanying the formation of the upper layer film. Specific examples of the heat treatment include a heat treatment for curing the liquid for forming the upper layer film.

The processing module 17 is a DEV module that performs a resist film developing process after exposure by the liquid processing unit U1 and the heat processing unit U2. The liquid processing unit U1 of the processing module 17 applies the developer on the surface of the wafer W that has been exposed and then rinses the surface of the wafer W with a rinsing liquid to perform the development processing of the resist film. The heat treatment unit (U2) of the treatment module (17) performs various heat treatments accompanying development processing. Specific examples of the heat treatment include PEB (Post Exposure Bake) before development processing and post-baking (PB) after development processing.

In the processing block 5, a shelf unit U10 is provided on the carrier block 4 side and a shelf unit U11 is provided on the interface block 6 side. The shelf unit U10 is provided so as to extend from the bottom surface to the processing module 16 and is divided into a plurality of cells arranged in the vertical direction. An elevating arm A7 is provided in the vicinity of the lathe unit U10. The lifting arm A7 lifts the wafer W between the cells of the lathe unit U10. The shelf unit U11 is installed so as to extend from the bottom surface to the upper portion of the processing module 17 and is divided into a plurality of cells arranged in the vertical direction.

The interface block 6 incorporates a transfer arm A8 and is connected to the exposure apparatus 3. [ The transfer arm A8 transfers the wafer W placed on the lathe unit U11 to the exposure apparatus 3 and receives the wafer W from the exposure apparatus 3 and returns the wafer W to the lathe unit U11 .

The substrate processing system 1 performs coating and developing processing in the following procedure. First, the transfer arm A1 transfers the wafer W in the carrier 11 to the lathe unit U10. The wafer W is placed on the cell for the processing module 14 by the elevation arm A7 and the transfer arm A3 is transferred to each unit in the processing module 14. [ The liquid processing unit U1 and the heat treatment unit U2 of the processing module 14 form a lower layer film on the surface of the wafer W carried by the transfer arm A3. When the formation of the lower layer film is completed, the transfer arm A3 returns the wafer W to the lathe unit U10.

Subsequently, the wafer W returned to the lathe unit U10 is placed in the cell for the processing module 15 by the lifting arm A7, and the carrying arm A3 is returned to each unit in the processing module 15 . The liquid processing unit U1 and the heat processing unit U2 of the processing module 15 form a resist film on the lower layer film of the wafer W carried by the transfer arm A3. When the formation of the resist film is completed, the transfer arm A3 returns the wafer W to the lathe unit U10.

Subsequently, the wafer W returned to the lathe unit U10 is placed on the cell for the processing module 16 by the lifting arm A7, and the carrying arm A3 is returned to each unit in the processing module 16 . The liquid processing unit U1 and the heat processing unit U2 of the processing module 16 form an upper layer film on the resist film of the wafer W carried by the transfer arm A3. When the formation of the upper layer film is completed, the transfer arm A3 returns the wafer W to the lathe unit U10.

Subsequently, the wafer W returned to the lathe unit U10 is placed on the cell for the processing module 17 by the elevation arm A7, and the direct transfer arm A6 is transferred to the lathe unit U11. And the transfer arm A8 sends the wafer W to the exposure apparatus 3. [ When the exposure processing in the exposure apparatus 3 is completed, the transfer arm A8 stores the wafer W from the exposure apparatus 3 and returns it to the lathe unit U11.

The transfer arm A3 of the processing module 17 then transfers the wafer W returned to the lathe unit U11 to each unit in the processing module 17. [ The liquid processing unit U1 and the heat processing unit U2 of the processing module 17 perform the development processing of the resist film of the wafer W carried by the transfer arm A3 and the heat treatment accompanying thereto. When the development of the resist film is completed, the transfer arm A3 transfers the wafer W to the lathe unit U10.

Subsequently, the wafer W transferred to the lathe unit U10 is placed in the receiving cell of the lifting arm A7, and the transferring arm A1 is returned to the carrier 11. Then, Thus, the coating and developing process is completed.

[Substrate heat treatment apparatus]

Next, the heat treatment unit U2 will be described in detail as an example of the substrate heat treatment apparatus. 4, the heat treatment unit U2 has a heat plate 20, a support base 30, a plurality of temperature sensors 40, a lifting mechanism 50, and a control unit 100. [

The heat plate 20 has a disk shape and includes a plurality of heaters 21 therein. The heat plate 20 functions as a loading section for loading the wafers W and the heater 21 functions as a heat processing section for heating the wafers W on the loading section. The heat plate 20 is divided into a plurality of regions when viewed in a plan view, and the heaters 21 are arranged for each region. Fig. 5 is a plan view showing an example of the arrangement of the heater 21. Fig. The heat plate 20 shown in Fig. 5 has a central region 20a, two regions 20b surrounding the region 20a, and four regions 20c, which also surround the region 20b. And a total of seven heaters 21 are built in each of the regions 20a, 20b, and 20c.

On the heat plate 20, a plurality of proximity fins 22 dotted along the upper surface of the heat plate 20 are provided. The plurality of proximity fins 22 support the wafer W to be stacked on the heating plate 20 and secure a gap between the heating plate 20 and the wafer W.

The support base (30) has a bottom plate (31) and a peripheral wall (32). The bottom plate (31) faces the heat plate (20). The peripheral wall 32 is installed along the periphery of the bottom plate 31 and supports the outer periphery of the heat plate 20. In the state where the peripheral wall 32 supports the heat plate 20, a cavity 33 is formed in the support base 30.

A plurality of temperature sensors (40) are arranged corresponding to a plurality of portions of the wafer (W) on the heat plate (20). That is, the temperature sensor 40 is dotted along the plane opposing the wafer W on the heat plate 20. As an example, a plurality of temperature sensors 40 are mounted on the lower surface of the heat plate 20 in the cavity 33. In the example shown in Fig. 5, seven temperature sensors 40 are provided for each of the regions 20a, 20b, and 20c, and the respective temperature sensors 40 are disposed under the heater 21. [

The plurality of temperature sensors 40 need only be disposed so as to correspond to a plurality of portions of the wafer W, and therefore, it is not always necessary to arrange them as described above. For example, the temperature sensor 40 may not be mounted on the lower surface of the heat plate 20, and the temperature sensor 40 may be embedded in the heat plate 20 together with the heater 21. [ A plurality of temperature sensors 40 may not always be disposed for each of the regions 20a, 20b, and 20c.

The lifting mechanism 50 has a plurality of (for example, three) lifting pins 51 and a driving portion 52. The lift pin (51) penetrates through the peripheral wall (32) and the heat plate (20). The upper portion of the lift pin 51 protrudes onto the heat plate 20 with the lift of the lift pin 51 and is accommodated in the heat plate 20 along with the descent of the lift pin 51. The driving unit 52 incorporates a driving source such as a motor or an air cylinder, and raises and lowers the lift pins 51. The lifting mechanism (50) lifts the wafer W on the heat plate (20) by lifting the lifting pin (51).

The control unit 100 controls the heater 21 based on the temperatures detected by the plurality of temperature sensors 40 and controls the temperature detected by the plurality of temperature sensors 40 to the center A position corresponding to the center of temperature is calculated, and a heat treatment state of the wafer W is detected based on the position of the center of temperature. The control unit 100 may be configured to acquire the temperature detected by the plurality of temperature sensors 40, to calculate the position of the temperature center corresponding to the center of the temperature when the temperature is regarded as the mass, , And a heat treatment state detecting device for detecting the heat treatment state of the wafer (W).

The control unit 100 includes a temperature acquisition unit 111, a heater control unit 112, a wafer transfer control unit 113, a central calculation unit 114, a difference calculation unit 115, An error notification unit 117, a position information output unit 118, a data storage unit 121,

The temperature acquisition unit 111 acquires the temperatures detected by the plurality of temperature sensors 40 and stores them in the data storage unit 121. [ The heater control unit 112 controls the plurality of heaters 21 based on the temperature stored in the data storage unit 121 by the temperature acquisition unit 111. [ The wafer transfer control section 113 controls the transfer arm A3 and the elevation mechanism (not shown) so as to carry and load the wafer W onto the heat plate 20 and transfer the wafer W from the heat plate 20. [ 50).

The center calculation unit 114 calculates the position of the temperature center based on the temperature stored in the data storage unit 121 and stores the calculation result in the data storage unit 121. [ The difference calculating unit 115 obtains the temperature center position stored in the data storage unit 121, calculates the difference between the position of the temperature center and the reference position, and stores the calculation result in the data storage unit 121. [ The reference position is determined based on, for example, the position of the temperature center when the wafer W is normally heat-treated. The heat treatment state detection unit 116 detects the heat treatment state of the wafer W based on the difference between the position of the temperature center and the reference position.

The abnormality notification unit 117 outputs to the display unit 122 information for notifying the abnormality of the heat treatment state. The position information output unit 118 outputs information on the position of the temperature center to the display unit 122. [ The display unit 122 outputs information output from the error notification unit 117 and the position information output unit 118 as a display image.

Such a control unit 100 is configured by, for example, one or a plurality of control computers. In this case, each element of the control unit 100 is configured by cooperation of a processor, a memory, a monitor, and the like of the control computer. The program for causing the control computer to function as the control unit 100 may be recorded on a computer-readable recording medium. In this case, the recording medium records a program for causing the apparatus to execute a substrate heat treatment method to be described later. Examples of the computer-readable recording medium include a hard disk, a compact disk, a flash memory, a flexible disk, a memory card, and the like.

The hardware constituting each element of the control unit 100 is not necessarily limited to a processor, a memory, and a monitor. For example, each element of the control section 100 may be constituted by an electric circuit specialized for the function, or may be constituted by an ASIC (Application Specific Integrated Circuit) integrated with the electric circuit.

The control unit 100 may be divided into a plurality of hardware units. For example, the control unit 100 may be divided into hardware for controlling the heat treatment unit U2 and hardware for configuring the heat treatment state detecting device. These hardware may be connected by either wired or wireless, or may be disposed at a place separated from each other and connected via a network line.

[Substrate Heat Treatment Method]

Next, as an example of the substrate heat treatment method, the heat treatment procedure of the wafer W by the heat treatment unit U2 will be described.

As shown in Fig. 6, first, the control section 100 executes step S01. In step S01, the temperature acquisition section 111 acquires the temperatures detected by the plurality of temperature sensors 40. Based on the temperatures acquired by the temperature acquisition section 111, the heater control section 112 controls the plurality of heaters (21). Specifically, the heater control unit 112 adjusts the supply power to the plurality of heaters 21 so that the temperature detected by the plurality of temperature sensors 40 approaches the target value.

Subsequently, the control section 100 executes step S02. In step S02, the transfer arm A3 and the elevating mechanism 50 load the wafer W onto the hot plate 20 under the control of the wafer transfer control unit 113. [ The wafer W placed on the heat plate 20 is heated by the heat from the heater 21. In other words, step S02 includes heating the wafer W on the heat plate 20 by the heater 21. [

Subsequently, the control unit 100 executes steps S03 and S04. In step S03, the temperature acquisition unit 111 acquires the temperatures detected by the plurality of temperature sensors 40, and stores them in the data storage unit 121. [ In step S04, the heater control section 112 controls the heater 21 based on the temperature acquired by the temperature acquisition section 111. [ Specifically, the temperature acquisition unit 111 adjusts the power supplied to the plurality of heaters 21 so that the temperature detected by the plurality of temperature sensors 40 is brought close to the target value.

Subsequently, the control section 100 executes steps S05 and S06. In step S05, the center calculating section 114 calculates the position of the temperature center, and stores the calculation result in the data storage section 121. [ The position of the center of the temperature can be calculated as a weighted average value of the coordinates when the temperature is the weight. For example, the center calculating section 114 calculates the position of the temperature center in the plane parallel to the wafer W as the first center position. The first center position can be calculated by the following equation.

&Quot; (3) "

&Quot; (4) "

X, Y: Position of center of temperature in Cartesian coordinate system

xi, yi: the position of the temperature sensor in the orthogonal coordinate system

Ti: temperature detected by the temperature sensor

n: the number of the temperature sensors

In step S06, the difference calculating section 115 acquires the position of the center of temperature stored in the data storage section 121, calculates the difference between the position of the center of temperature and the reference position, and outputs the calculation result to the data storage section 121 . As described above, the reference position is determined based on the position of the center of temperature when, for example, the wafer W is normally heat-treated.

As a specific example of the reference position, an average value of the position of the center of temperature calculated in the past plural times normal heat treatment can be mentioned. The reference position is previously recorded in the data storage unit 121, for example. The reference position may be calculated by the difference calculator 115 or the like prior to step S06. That is, the control unit 100 may be configured to also execute calculation of the reference position. The substrate heat treatment method may further include calculating a reference position.

Subsequently, the control section 100 executes step S07. In step S07, the heat treatment state detection unit 116 detects the heat treatment state of the wafer W based on the position of the temperature center. As an example of the detection of the heat treatment state, it is possible to detect whether the heat treatment state is normal or abnormal. For example, when the difference between the position of the center of temperature and the reference position is within the permissible range, the heat treatment state detection unit 116 detects that the heat treatment state of the wafer W is normal, and the difference between the position of the center of temperature and the reference position It is detected that the heat treatment state of the wafer W is abnormal.

As a specific example of the allowable range, there is a standard deviation of the position of the center of temperature calculated in the past plural times of normal heat treatment. The allowable range may be obtained by multiplying the standard deviation by a predetermined magnification (for example, three times). The allowable range is, for example, recorded in the data storage unit 121 in advance. The allowable range may be calculated by the heat treatment state detection unit 116 or the like prior to step S07. That is, the control unit 100 may be configured to also calculate the allowable range. The substrate heat treatment method may further include calculating an allowable range.

When it is detected in step S07 that the heat treatment state is normal, the control section 100 executes step S08. In step S08, the wafer transfer control section 113 detects whether or not the set time has elapsed from the start of heating of the wafer W. [ In step S08, when it is detected that the set time has not yet elapsed, the control section 100 returns the processing to step S03. If it is detected in step S08 that the set time has elapsed, the control section 100 executes step S09. In step S09, the transfer arm A3 and the elevating mechanism 50 carry the wafer W from the top of the hot plate 20 under the control of the wafer transfer control unit 113. [ Thus, the normal heat treatment of the wafer W is completed.

If it is detected in step S07 that the heat treatment state is abnormal, the control section 100 executes steps S10 and S11. In step S10, the abnormality notification unit 117 outputs information for notifying the abnormality of the heat treatment state to the display unit 122, and the display unit 122 outputs the information as the display image. In step S11, the position information output unit 118 outputs information about the position of the temperature center to the display unit 122, and the display unit 122 outputs the information as the display image.

As an example, the position information output unit 118 outputs the locus information of the difference between the position of the center of temperature and the reference position based on the data stored in the data storage unit 121 by repeating the steps S03 to S08, (122) outputs the information as a graph. Further, the locus information means a temporal change of the position (including the positional difference). The arrangement of the positional information stored in the data storage unit 121 in the time series by repeating the steps S03 to S08 corresponds to the locus information.

After executing steps S10 and S11, the control unit 100 ends the heat treatment.

The heat treatment unit U2 described above includes a heat plate 20 for mounting the wafer W, a heater 21 for heating the wafer W on the mounting portion, a wafer W on the heat plate 20, A plurality of temperature sensors 40 arranged so as to respectively correspond to a plurality of positions of the control unit 100; The control unit 100 controls the heater 21 based on the temperatures detected by the plurality of temperature sensors 40 and controls the temperature detected by the plurality of temperature sensors 40 to the center The position of the center of the temperature is calculated, and the heat treatment state of the wafer W is detected based on the position of the center of temperature.

According to this heat treatment unit U2, the heat treatment state of the wafer W is detected based on the position of the temperature center. The state of heat treatment of the wafer W may not only be abnormal in the whole of the wafer W but may be limited to a certain extent in a part of the wafer W Quot;). As a factor causing a partial abnormality in the heat treatment state, a part of the wafer W is separated from the heat plate 20 (hereinafter referred to as " lifted up of the wafer W " ]. The rise of the wafer W may occur due to, for example, a rise in a trace amount of particles or a warp of the wafer W. [ The position of the center of the temperature fluctuates to a high sensitivity depending on a partial abnormality in the heat treatment state as exemplified below.

7A is a graph showing a change with time in the temperature detected by the temperature sensor 40 when the heating of the wafer W is normally performed by the illustrated heating plate 20 in Fig. 7 (b) is a graph showing the relationship between the temperature detected by the temperature sensor 40 and the temperature of the wafer W when the heating is performed in a state where the lifting of the wafer W occurs on the upper side of the heating plate 20 shown in Fig. Which is a graph showing a change in the temperature. 7A and 7B, the detection value of each temperature sensor 40 is changed to gradually approach the set temperature after the temperature has decreased after the start of heating. The temperature drop after the start of heating is accompanied by the heat of the heater 21 being absorbed by the wafer W side. This is because the heater 21 is controlled based on the detection value of the temperature sensor 40 because the lowered temperature is restored to the set temperature side.

FIG. 8A is a graph showing the locus of the position of the temperature center calculated using the temperature shown in FIG. 7A. FIG. FIG. 8B is a graph showing the locus of the position of the temperature center calculated using the temperature shown in FIG. 7B. FIG. 8A and 8B correspond to the up, down, left, and right directions of Fig. 5, respectively. In Fig. 8 (b), the position of the center of temperature is greatly shifted upward as compared with Fig. 8 (a). This is considered to be due to the fact that the lowering of the temperature accompanying the loading of the wafer W is smaller in the upper side of the city because the rising of the wafer W occurs on the upper side of the city.

As illustrated in Fig. 8, the position of the center of temperature fluctuates to a high sensitivity depending on a partial abnormality in the heat treatment state. Therefore, the partial abnormality of the heat treatment state can be detected with high sensitivity based on the position of the center of temperature. Therefore, it is possible to more reliably detect an abnormality in the heat treatment state.

The control unit 100 calculates the position of the center of the temperature in the plane parallel to the wafer W as the first center position and the position of the center of the temperature in the radial direction perpendicular to the center of the wafer W May also be calculated as the second center position and the heat treatment state of the wafer W may be detected on the basis of the first and second center positions.

The heat plate 20 shown in Fig. 5 is divided into three regions 20a, 20b, and 20c arranged concentrically with the wafer W in the radial direction. Since the region 20b is divided into two regions arranged in the declination direction (circumferential direction), two temperature sensors 40 are arranged in the region 20b. Since the region 20c is divided into four regions arranged in the declination direction, four temperature sensors 40 are arranged in the region 20c. In this case, the temperature Ta detected by the temperature sensor 40 of the region 20a is regarded as the mass of the region 20a, and the temperature detected by the two temperature sensors 40 of the region 20b The average value Tb of the temperature detected by the four temperature sensors 40 in the region 20c is regarded as the mass of the region 20b and the average value Tb of the region 20c is regarded as the mass It is possible to calculate the second center position.

R = (ra · Ta + rb · Tb + rc · Tc) / (Ta + Tb + Tc)

R: second center position

Ra: Position of the region 20a in the radial direction (distance from the center of the wafer W to the region 20a)

rb: position of the region 20b in the radial direction (distance from the center of the wafer W to the region 20b)

rc: position of the region 20c in the radial direction (distance from the center of the wafer W to the region 20c)

Ta: the temperature detected by the temperature sensor 40 of the region 20a

Tb: the average value of the temperatures detected by the two temperature sensors 40 of the region 20b

The average value of the temperatures detected by the four temperature sensors 40 of the Tb: region 20c

The first central position fluctuates with high sensitivity depending on a partial abnormality in the heat treatment state, but is unlikely to vary as long as the temperature distribution becomes point symmetrical with respect to the center of the wafer W. [ A specific example of such a case is a case in which the central portion of the wafer W floats on the particle and the whole peripheral portion of the wafer W floats uniformly due to the warpage of the wafer W have.

On the other hand, the second central position varies depending on the temperature distribution along the radial direction of the wafer W. 9 is a graph exemplifying the locus of the second center position during the heat treatment. The r axis in the figure is the center of the polar coordinate system around the wafer W, FP is the locus of the second center position, and O1 is the center position of the wafer W and the middle position of the periphery. FIG. 9A illustrates a case where the central portion of the wafer W is floating. In this case, the locus FP is largely shifted toward the center side of the wafer W with respect to the intermediate position O1. FIG. 9 (b) illustrates a case in which the peripheral edge of the wafer W is floated. In this case, the trajectory FP is largely shifted toward the peripheral edge of the wafer W with respect to the intermediate position O1. As described above, the second center position also fluctuates with high sensitivity even when the temperature distribution is point-symmetrical with respect to the center of the wafer W. [ Therefore, by detecting the heat treatment state of the substrate based on both the first and second center positions, it is possible to more reliably detect an abnormality in the heat treatment state.

As described above, the control section 100 may calculate the second center position by considering the average value of the temperatures detected by the plurality of temperature sensors 40 at positions mutually equal in the radial direction as the mass of the position. The control unit 100 regards the average value of the temperatures detected by the temperature sensors in each of the plurality of regions 20a, 20b, and 20c arranged in the radial direction concentric with the wafer W as the mass of the region, 2 center position may be calculated. In these cases, the second center position can be calculated with higher accuracy.

The control unit 100 uses a predetermined reference position based on the position of the center of temperature when the wafer W is normally heated and performs a heat treatment of the wafer W based on the difference between the position of the center of temperature and the reference position To detect the state. As a result, the heat treatment state of the wafer W is detected based on the components separated from the reference position among the positions of the temperature center. Based on the components separated from the reference position, the criterion for determining whether the heat treatment state is normal or abnormal can be simplified.

Further, since the control unit 100 may be configured to detect the heat treatment state based on the position of the temperature center, it is not essential that the control unit 100 is configured to use the reference position.

The control unit 100 uses the average value of the position of the center of temperature calculated in the plurality of times of normal heating as the reference position and determines the allowable range based on the standard deviation of the positions of the temperature centers calculated in the normal heating And it is configured to detect that the heat treatment state of the wafer W is abnormal when the difference between the position of the temperature center and the reference position is outside the allowable range.

10 is a graph showing the locus of the difference between the position of the center of temperature and the reference position shown in Fig. 8 (b). The dashed line in Fig. 9 indicates the allowable range. At the time when the locus of Fig. 9 comes out of the one-dot chain line, it is detected that the heat treatment state of the wafer W is abnormal. As described above, an abnormality in the heat treatment state can be detected by a simple criterion of whether or not the position of the temperature center is within an allowable range. In addition, by using the average value as the reference position and using the allowable range determined based on the standard deviation, an appropriate deviation can be allowed, thereby reducing unnecessary abnormality detection.

It may be detected that the heat treatment state of the wafer W is abnormal even when the difference between the second central position and the reference position is outside the permissible range. Dot chain lines LL1 to LL2 in Fig. 9 exemplify the allowable range of the second reference position.

Since the control unit 100 may be configured to detect the heat treatment state based on the position of the temperature center, a specific method of detecting the heat treatment state based on the position of the temperature center is not limited to the above.

The control unit 100 is also configured to output information about the position of the temperature center. Based on the position of the center of temperature, it is also possible to grasp in which direction the abnormality of the heat treatment state occurred. Thus, by outputting information about the position of the center of temperature, it is possible to provide information useful for specifying the position of the cause of the abnormality in the heat treatment state.

In addition, since the control unit 100 may be configured to detect the heat treatment state, it is not essential that the control unit 100 is configured to output information about the position of the temperature center.

The control unit 100 is configured to output the locus information of the difference between the position of the temperature center and the reference position as an example of the information about the position of the temperature center. Thus, the locus information of the components separated from the reference position among the positions of the center of temperature is output. According to the locus information of the components separated from the reference position, it is possible to more easily grasp in which direction the abnormality of the heat treatment state occurred. Therefore, it is possible to provide information that is more beneficial for specifying a position as a cause of abnormality in the heat treatment state. For example, based on Fig. 9, it can be estimated that the wafer W is floating on the upper side of Fig. 5.

The control unit 100 may be configured to superimpose the locus information of the position of the temperature center and the locus information of the reference position as information on the position of the center of temperature and may output information indicating the orientation And output the same. The control unit 100 may be configured to output only the locus information of the position of the temperature center itself as the information about the position of the temperature center.

The heater 21 may be controllable for each of a plurality of processing regions (regions 20a, 20b, and 20c) arranged along the wafer W. The controller 100 may be configured such that the heat treatment is insufficient It may be configured to specify one processing region and to control the heat treatment section so as to promote the heat treatment of the processing region. In this case, the reliability of the heat treatment can be improved by performing the heat treatment according to the positional information of the temperature center. With reference to FIG. 11, a specific example of the heat treatment process including promoting the heat treatment of the treatment region where the heat treatment is insufficient will be described.

In the heat treatment procedure shown in Fig. 11, when it is detected that the heat treatment state is abnormal in step S07, the control section 100 executes step S20. In step S20, the heater control unit 112 confirms whether or not the abnormality in the heat treatment state is within the adjustable range. For example, the heater control section 112 confirms whether or not the temperature in the treatment region where the heat treatment is insufficient is within the adjustable range. The adjustable range is a range that can be returned to the allowable range by adjusting the output of the heater 21, and can be set in advance based on experiments.

If it is determined in step S20 that the abnormality in the heat treatment state is within the adjustable range, the control section 100 executes step S21. In step S21, the heater control unit 112 controls the heater 21 so as to promote the heat treatment of the treatment area where the heat treatment is insufficient. For example, the heater control unit 112 increases the output of the heater 21 in the processing region where the heat treatment is insufficient. Thereafter, the control section 100 advances the processing to step S08.

If it is determined in step S20 that the abnormality in the heat treatment state is not within the adjustable range, the control section 100 ends the processing after executing steps S22 and S23 similarly to steps S10 and S11.

Although the embodiments have been described above, the present invention is not necessarily limited to the above-described embodiments, and various modifications are possible without departing from the gist of the invention. For example, the heat treatment unit for heating the wafer W on the mounting unit is not limited to the heater 21 described above, and may be an infrared light source configured to radiantly heat the wafer W. [ The heat treatment unit is not limited to the one for heating purposes. For example, the heat treatment section may be a cooler for cooling the wafer W. [ The object of the heat treatment is not limited to a semiconductor wafer but may be, for example, a glass substrate, a mask substrate, or an FPD (Flat Panel Display).

20: Heat plate (loading part)
21: heater (heat treatment part)
40: Temperature sensor
100:
U2: Heat treatment unit (substrate heat treatment apparatus)
W: Wafer (substrate)

Claims (22)

A loading section for loading the substrate,
A heating section for heating or cooling the substrate on the mounting section;
A plurality of temperature sensors arranged corresponding to a plurality of portions of the substrate on the mounting portion,
Controlling the heat processing unit based on the temperatures detected by the plurality of temperature sensors; calculating a position of a center of temperature corresponding to the center of the temperature detected by the plurality of temperature sensors as a mass; And a control section configured to detect a heat treatment state of the substrate based on the position of the temperature center. The method according to claim 1,
Wherein the control unit calculates a position of the temperature center in a plane parallel to the substrate as a first center position and sets a position of the temperature center in a radial direction orthogonal to the center of the substrate as a second center position And the heat treatment state of the substrate is detected based on the first and second center positions. 3. The method of claim 2,
Wherein the control section calculates the second center position by considering an average value of temperatures detected by a plurality of temperature sensors at mutually equal positions in the radial direction as the mass of the position. 3. The method of claim 2,
Wherein the control unit calculates the second center position by considering an average value of temperatures detected by the temperature sensor in each of a plurality of regions arranged concentrically with the substrate in the radial direction as the mass of the region, Substrate heat treatment apparatus. 5. The method according to any one of claims 1 to 4,
Wherein the control unit uses a predetermined reference position based on the position of the center of temperature when the substrate is normally heat treated and determines a heat treatment state of the substrate based on a difference between the position of the temperature center and the reference position Wherein the substrate processing apparatus is configured to detect the substrate. 6. The method of claim 5,
Wherein the control unit uses the average value of the position of the center of temperature calculated in the normal heat treatment a plurality of times as the reference position and determines the standard deviation of the position of the center of temperature calculated in the normal heat treatment a plurality of times Wherein the allowable range is also used to detect that the heat treatment state of the substrate is abnormal when the difference between the position of the temperature center and the reference position is outside the allowable range. 5. The method according to any one of claims 1 to 4,
Wherein the control unit is configured to further execute outputting information on the position of the temperature center. 6. The method of claim 5,
Wherein the control unit is configured to further execute outputting sign information of a difference between the position of the temperature center and the reference position. 5. The method according to any one of claims 1 to 4,
The heat treatment section is controllable for each of a plurality of processing regions arranged along the substrate,
Wherein the control section is configured to specify the processing region where the heat treatment is insufficient based on the position of the temperature center and to control the heat treatment section to promote the heat treatment of the processing region. 5. The method according to any one of claims 1 to 4,
Wherein the control unit calculates the position of the temperature center by equations (1) and (2).
[Equation 1]

&Quot; (2) "

X, Y: position of the temperature center in the rectangular coordinate system
xi, yi: the position of the temperature sensor in the orthogonal coordinate system
Ti: temperature detected by the temperature sensor
n: the number of the temperature sensors Loading the substrate on the loading portion,
Heating or cooling the substrate on the loading section by a heat treatment section,
Detecting a temperature by a plurality of temperature sensors arranged corresponding to a plurality of portions of the substrate on the mounting portion,
Controlling the heat treatment unit based on the temperatures detected by the plurality of temperature sensors,
Calculating a position of a center of temperature corresponding to the center of the case where the temperature detected by the plurality of temperature sensors is regarded as a mass,
And detecting a heat treatment state of the substrate based on the position of the temperature center. 12. The method of claim 11,
Calculating a position of the temperature center in a plane parallel to the substrate as a first center position and calculating a position of the temperature center in a radial direction perpendicular to the center of the substrate as a second center position, And a heat treatment state of the substrate is detected based on the first and second center positions. 13. The method of claim 12,
And the second center position is calculated by considering the average value of the temperatures detected by the plurality of temperature sensors at positions equal to each other in the radial direction as the mass of the position. 13. The method of claim 12,
And the second center position is calculated by considering an average value of temperatures detected by the temperature sensor in each of a plurality of regions arranged concentrically with the substrate in the radial direction as the mass of the region. 15. The method according to any one of claims 11 to 14,
Wherein a predetermined reference position is used based on a position of the temperature center when the substrate is normally heat treated and a heat treatment state of the substrate is detected based on a difference between the position of the temperature center and the reference position, Heat treatment method. 16. The method of claim 15,
An average value of the position of the center of temperature calculated in the normal heat treatment of plural times is used as the reference position and the allowable range determined based on the standard deviation of the position of the temperature center calculated in the normal heat treatment a plurality of times is And when the difference between the position of the temperature center and the reference position is outside the allowable range, detecting that the heat treatment state of the substrate is abnormal. 15. The method according to any one of claims 11 to 14,
And outputting information on the position of the temperature center. 16. The method of claim 15,
And outputting the locus information of the difference between the position of the temperature center and the reference position. 15. The method according to any one of claims 11 to 14,
Further comprising: identifying a processing region that is insufficiently heat-treated based on the position of the temperature center; and promoting a heat treatment of the processing region. 15. The method according to any one of claims 11 to 14,
Wherein the position of the center of temperature is calculated by equations (1) and (2).
&Quot; (3) "

&Quot; (4) "

X, Y: position of the temperature center in the rectangular coordinate system
xi, yi: the position of the temperature sensor in the orthogonal coordinate system
Ti: temperature detected by the temperature sensor
n: the number of the temperature sensors A computer-readable recording medium having recorded thereon a program for causing a device to execute a substrate heat treatment method according to any one of claims 11 to 14. Obtaining a temperature detected by a plurality of temperature sensors arranged so as to respectively correspond to a plurality of locations on a substrate to be subjected to a heat treatment on a mounting portion, determining a position of a center of temperature corresponding to the center of the temperature, Based on the position of the temperature center, and to detect the heat treatment state of the substrate.

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