Heat treatment apparatus and heat treatment method

Abstract

To provide a heat treatment apparatus and a heat treatment method capable of improving the manufacturing yield of a semiconductor product using a heat-treated substrate.SOLUTION: The heat treatment apparatus 100 includes a plate member 10. A plurality of support members 13 are provided on the processing surface 11 of the plate member 10. A heating element 20 is provided under the plate member 10. The heating element 20 adjusts the temperature of the processing surface 11 to a predetermined processing temperature. The temperatures of portions of the processing surface 11 where the plurality of support members 13 are not provided are detected by the plurality of temperature sensors TS1. The heat treatment apparatus 100 further includes a controller 90. When the substrate W is placed on the plurality of support members 13, the controller 90 determines whether or not the downwardly distorted portion of the substrate W is in contact with the processing surface 11 based on the detection results of the plurality of temperature sensors TS1 and the information of the temperature change of the processing surface 11 when the normal heat processing is performed.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a heat treatment apparatus and a heat treatment method for performing heat treatment on a substrate. [Background technology]

[0002] Heat treatment devices are used to perform various treatments on substrates such as semiconductor substrates, substrates for FPDs (Flat Panel Displays) such as liquid crystal displays or organic EL (Electro Luminescence) displays, substrates for optical disks, substrates for magnetic disks, substrates for magneto-optical disks, substrates for photomasks, ceramic substrates, or substrates for solar cells.

[0003] Patent Document 1 describes, as an example of a heat treatment apparatus, a heat treatment unit that performs heat treatment on a substrate (wafer). The heat treatment unit includes a circular plate member (holding plate) that is slightly larger than the substrate. A heating element is provided on the underside of the plate member. A substrate placement position where the substrate should be placed is set on the upper surface of the plate member. In addition, a plurality of proximity sheets are provided on the upper surface of the plate member at multiple portions around the outer periphery of the substrate placement position, and a proximity pin is provided at the center of the substrate placement position.

[0004] Each proximity sheet has a fixed length and extends from an area inside the substrate placement position to an area outside the substrate placement position. A guide is provided on a portion of each proximity sheet that is located outside the substrate placement position.

[0005] In the heat treatment apparatus, the heating elements are driven to adjust the temperature of the plate member to a predetermined temperature. In this state, a substrate is placed on the plate member so that it is positioned inside the multiple guides and supported by the proximity pins and multiple proximity sheets. This allows the substrate to be heat-treated.

[0006] If the substrate is placed on the plate member without being accurately positioned, a portion of the substrate may climb onto the guides, causing the distance between the portion of the substrate and the plate member to deviate significantly from the preset distance, resulting in processing defects.

[0007] Therefore, a temperature sensor for detecting the temperature of the plate member is provided inside the plate member of the heat processing unit of Patent Document 1. When a substrate is placed on the plate member, it is determined whether the substrate is mounted on the guide based on the temperature detected by the temperature sensor. It is also determined whether dust is attached to the substrate. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Patent No. 3577436 Summary of the Invention [Problem to be solved by the invention]

[0009] In recent years, substrates have become thinner depending on the application of semiconductor products. In addition, the materials used for substrates may be limited to specific materials. Therefore, depending on the thickness and material of the substrate to be processed, the rigidity of the substrate may be relatively low.

[0010] A substrate with low rigidity is prone to warping and other distortions when the substrate is subjected to various processes. If the degree of distortion is large, there is a possibility that a part of the substrate may come into contact with the plate member when the substrate is placed on the plate member.

[0011] Furthermore, when the substrate is accurately positioned on the plate member, multiple portions of the substrate are supported by the proximity pins and multiple proximity sheets. However, if the substrate has excessively low rigidity, the portions of the substrate that are not supported by the proximity pins and multiple proximity sheets may come into contact with the plate member due to distortion caused by deflection under their own weight.

[0012] When the substrate comes into contact with the plate member, the temperature distribution of the plate member varies, making it impossible to perform the desired heat treatment on the substrate. If a substrate that has not undergone the desired heat treatment is sent to a subsequent manufacturing line as if it had undergone the desired heat treatment, the yield of semiconductor products will decrease.

[0013] An object of the present invention is to provide a heat treatment apparatus and a heat treatment method that can improve the manufacturing yield of semiconductor products using substrates after heat treatment. [Means for solving the problem]

[0014] A heat treatment apparatus according to one aspect of the present invention is a heat treatment apparatus for performing heat treatment on a substrate, comprising: a plate member having a processing surface facing upward; a plurality of support members provided on the processing surface so as to be able to support the lower surface of the substrate; a heat treatment section for performing heat treatment on the substrate supported by the plurality of support members on the processing surface by adjusting the temperature of the processing surface to a predetermined processing temperature; a temperature detection section for detecting the temperature of a portion of the processing surface where the plurality of support members are not provided; a mounting device for mounting the substrate on the plurality of support members; and a mounting device for mounting a sample of the same type as the substrate on the plurality of support members by the mounting device while the temperature of the processing surface is adjusted to the processing temperature. and a contact determination unit that, when the substrate is placed on the plurality of support members by the mounting device with the temperature of the processing surface adjusted to the processing temperature, acquires the temperature change on the processing surface from the time the substrate is placed until the certain time has elapsed based on the detection result of the temperature detection unit, and determines whether a portion of the substrate that is warped downward is in contact with the processing surface based on the acquired temperature change on the processing surface and the reference temperature information.

[0015] A heat treatment method according to another aspect of the present invention is a heat treatment method for performing heat treatment on a substrate using a heat treatment apparatus, the heat treatment apparatus including a plate member having a treatment surface facing upward and a plurality of support members provided on the treatment surface so as to be able to support a lower surface of the substrate, the heat treatment method including the steps of: storing, as reference temperature information, information on a temperature change of the treatment surface from a time when a sample substrate of the same type as the substrate is placed on the plurality of support members, with the temperature of the treatment surface adjusted to a predetermined treatment temperature, until a certain time has passed without the sample substrate coming into contact with the treatment surface; after the storing step, placing the substrate on the plurality of support members, with the temperature of the treatment surface adjusted to the predetermined treatment temperature; the step of adjusting the temperature of the processing surface to the processing temperature, thereby performing heat treatment on the substrate supported by the plurality of support members on the processing surface; the step of detecting the temperature of the portion of the processing surface where the plurality of support members are not provided by a temperature detection unit; and the step of, when the substrate is placed on the plurality of support members with the temperature of the processing surface adjusted to the processing temperature, acquiring a temperature change on the processing surface from the time the substrate is placed until the certain time has elapsed based on the detection result of the temperature detection unit, and determining whether a portion of the substrate that is warped downward is in contact with the processing surface based on the acquired temperature change on the processing surface and the reference temperature information stored in the step of storing. [Effects of the Invention]

[0016] According to the present invention, it is possible to improve the manufacturing yield of products using substrates after heat treatment. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a diagram illustrating a basic configuration of a heat treatment apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is an enlarged plan view of the plate member of FIG. [Figure 3]FIG. 10 is a diagram showing the results of confirmation tests on the first substrate and the second substrate. [Figure 4] FIG. 10 is a diagram showing the results of confirmation tests on the first substrate and the third substrate. [Figure 5] FIG. 10 is a diagram showing an example of estimated temperature changes acquired by first to sixth sensors when normal heating processing is performed. [Figure 6] FIG. 10 is a diagram showing an example of estimation of temperature changes acquired by the first to sixth sensors when a part of the substrate comes into contact with the processing surface. [Figure 7] 10 is a flowchart illustrating an example of a contact determination process. [Figure 8] FIG. 10 is an enlarged plan view of a plate member according to another embodiment. [Figure 9] FIG. 10 is an enlarged plan view of a plate member according to yet another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0018] A heat treatment apparatus and a heat treatment method according to an embodiment of the present invention will be described below with reference to the drawings. In the following description, the term "substrate" refers to a substrate for a flat panel display (FPD) used in a liquid crystal display device or an organic electroluminescence (EL) display device, a semiconductor substrate, an optical disk substrate, a magnetic disk substrate, a magneto-optical disk substrate, a photomask substrate, a ceramic substrate, or a solar cell substrate. The substrate described below is a substrate having at least a portion of its outer edge circular, specifically a circular substrate with a positioning notch or orientation flat formed in part of its outer peripheral edge. The substrate is made of silicon or silicon carbide and has a thickness of less than 775 μm. In the following description, a heat treatment apparatus for heat treatment of a substrate will be described as an example of a heat treatment apparatus.

[0019] 1. Basic configuration of heat treatment equipment 1 is a diagram illustrating the basic configuration of a heat treatment apparatus according to an embodiment of the present invention. As shown in FIG. 1, the heat treatment apparatus 100 mainly includes a plate member 10, a heating element 20, a lifting device 40, a control device 90, an operation unit 98, and a presentation device 99.

[0020] The plate member 10 is a heat transfer plate having a predetermined thickness. The plate member 10 has a flat processing surface 11 facing upward and a mounting surface 12 facing downward. The processing surface 11 of the plate member 10 has an outer diameter larger than that of the substrate W to be heat-processed. The substrate W to be processed by the heat processing apparatus 100 according to this embodiment has an outer diameter of 200 mm.

[0021] 2 is an enlarged plan view of the plate member 10 of FIG. 1. As indicated by the thick dashed dotted line in FIG. 2, a circular substrate processing region PR is defined on the processing surface 11, in which the substrate W should be placed during heat processing. A plurality of (21 in this example) support members 13 and a plurality of (4 in this example) guide members 19 are provided on the processing surface 11 so as to protrude upward. In FIG. 1, some of the plurality of support members 13 and some of the plurality of guide members 19 are shown in a schematic side view together with the plate member 10. In addition, in FIG. 2 and subsequent figures, the plurality of support members 13 are indicated by black dots.

[0022] Each support member 13 is a spherical proximity ball that supports the underside of the substrate W, and is made of, for example, ceramic. The multiple support members 13 are distributed over the substrate processing region PR of the processing surface 11. In Figure 1, the substrate W supported by the multiple support members 13 on the plate member 10 is indicated by a dashed dotted line. The arrangement of the multiple support members 13 on the processing surface 11 will be described in detail below.

[0023] When a flat substrate W is supported by a plurality of support members 13, the size of the gap GA (Figure 1) formed between the substrate W and the processing surface 11 (the distance between the substrate W and the processing surface 11 in the vertical direction) is, for example, 80 μm or more and 100 μm or less.

[0024] The guide members 19 are made of a highly heat-resistant resin such as PEEK (polyether ether ketone). As shown in Fig. 2, the guide members 19 are provided on the periphery of the processing surface 11 and surround the substrate processing region PR. As shown in Fig. 1, the upper half of each guide member 19 has a truncated cone shape whose diameter gradually decreases toward the upper end. Thus, when the substrate W is placed on the support members 13 by the lifting pins 41 (described later), the outer peripheral surface of the upper half of each guide member 19 guides the outer peripheral edge of the substrate W to the substrate processing region PR on the processing surface 11.

[0025] A heating element 20 is attached to the mounting surface 12 of the plate member 10. The heating element 20 is formed of, for example, a mica heater or a Peltier element. A heat generation drive circuit 21 is connected to the heating element 20. The heat generation drive circuit 21 drives the heating element 20 under the control of a temperature control unit 91, which will be described later. This causes the heating element 20 to generate heat when the substrate W is heated.

[0026] As shown in Fig. 1, the plate member 10 has a plurality of (three in this example) through holes 14 formed therethrough in the vertical direction. The plate member 10 also has a plurality of (seven in this example) vertical holes 15 formed therein, extending from the mounting surface 12 to the vicinity of the treatment surface 11. Fig. 1 shows some of the vertical holes 15. The heating element 20 has a plurality of openings that open the internal spaces of the plurality of through holes 14 and the plurality of vertical holes 15 downward.

[0027] The plurality of through holes 14 of the plate member 10 are formed so that a plurality of lift pins 41, which will be described later, can be inserted therein, and are arranged at equal angular intervals on a circle whose base is the center CA of the substrate processing region PR (FIG. 2).

[0028] A plurality of temperature sensors for detecting the temperature of the processing surface 11 of the plate member 10 are provided at the bottoms of the plurality of vertical holes 15 (in the vicinity of the processing surface 11). In this example, six temperature sensors TS1 are provided in six of the seven vertical holes 15. These temperature sensors TS1 are used to determine whether the substrate W is in contact with the processing surface 11. Furthermore, one temperature sensor TS2 is provided in the remaining one of the seven vertical holes 15. This temperature sensor TS2 is used to control the driving state of the heating element 20.

[0029] The multiple temperature sensors TS1, TS2 are temperature detection elements having a characteristic value that changes depending on the temperature of the processing surface 11 of the plate member 10. The temperature detection elements may be thermocouples, resistance temperature detectors, or other elements. If the temperature detection elements are thermocouples, the characteristic value is a potential difference (thermoelectromotive force), and if the temperature detection elements are resistance temperature detectors, the characteristic value is an electrical resistance. Each of the temperature sensors TS1, TS2 outputs a detection value based on a characteristic value that corresponds to the temperature of the processing surface 11. The arrangement of the multiple temperature sensors TS1 when viewed in a plan view will be described in detail later.

[0030] 1, the lifting device 40 includes a plurality of (three in this example) lifting pins 41 and a connecting member 42. The lifting device 40 also includes a motor and a motor drive circuit, etc., not shown. Each of the plurality of lifting pins 41 is a rod-shaped member made of, for example, ceramic. The plurality of lifting pins 41 are connected to one another by the connecting member 42, and are held so as to extend in the vertical direction with portions of the plurality of lifting pins 41 inserted into the plurality of through-holes 14 of the plate member 10, respectively.

[0031] In the lifting device 40, a motor (not shown) operates under the control of a lifting control section 92 (described later), causing the connecting member 42 to move up and down. This causes the plurality of lifting pins 41 to move between an upper position where the upper ends of the plurality of lifting pins 41 are positioned above the upper ends of the plurality of guide members 19, and a lower position where the upper ends of the plurality of lifting pins 41 are positioned below the processing surface 11 of the plate member 10.

[0032] With this configuration, the lifting device 40 functions as a transfer section that receives the substrate W handed over from a robot outside the heat treatment device 100, places it on a plurality of support members 13, and raises the substrate W supported on the plurality of support members 13 to transfer it to a robot outside the heat treatment device 100.

[0033] The operation unit 98 includes, for example, a keyboard and a pointing device, and is configured to be operable by a user. The presentation device 99 includes a display and an audio output device (not shown). The control device 90 controls the operations of the heat generation drive circuit 21, the lifting device 40, the presentation device 99, etc. Details of the control device 90 will be described later.

[0034] 2. Details of the arrangement of the plurality of support members 13 and the plurality of temperature sensors TS1 <1> Contact of the substrate W with the processing surface 11 As explained in the summary of the invention, depending on the thickness and material of the substrate W to be processed, a portion of the substrate W supported by the plurality of support members 13 may come into contact with the processing surface 11.

[0035] Typically, when a substrate W is heated, the temperature of the processing surface 11 is maintained at a predetermined processing temperature (hereinafter referred to as the processing temperature) from the time before the heating process begins. Therefore, when the substrate W is placed on the support members 13 and a portion of the substrate W comes into contact with the processing surface 11, heat from the portion of the processing surface 11 that the substrate W comes into contact with is transferred to the substrate W. The local heat transfer on the processing surface 11 causes the temperature distribution on the processing surface 11 to vary greatly. Furthermore, during the heating process, part of the heat transferred from the heating element 20 to the processing surface 11 is dissipated through the substrate W, making it impossible to perform the desired heating process on the entire substrate W.

[0036] <2> Arrangement of multiple support members 13 In the heat treatment apparatus 100, it is preferable that a plurality of support members 13 be arranged on the processing surface 11 so as to reduce contact of the substrate W with the processing surface 11. To find a preferable arrangement of the plurality of support members 13, the inventors conducted various experiments and studies on various distortions that occur in circular substrates. As a result, the inventors discovered that a circular substrate with low rigidity tends to warp (deform) so that the center and its surrounding area bulges or dents in a direction perpendicular to the circular substrate. The inventors also discovered that a circular substrate with low rigidity tends to warp (deform) locally at the outer periphery and its surrounding area. Based on these findings, the inventors determined the arrangement of the plurality of support members 13. The arrangement of the plurality of support members 13 will be described in detail below.

[0037] In the processing surface 11 of the plate member 10 according to this embodiment, the substrate processing region PR includes a first region R1, a second region R2, and a third region R3. In Fig. 2, the first region R1 is indicated by low-density hatching. The first region R1 is a circular region based on the center CA of the substrate processing region PR, and its outer peripheral edge overlaps with three through holes 14. The three through holes 14 are for raising and lowering three lift pins 41 (Fig. 1).

[0038] 2, the second region R2 is provided with a low-density dot pattern. The second region R2 is an annular region adjacent to the first region R1 and surrounding the first region R1. The second region R2 has a constant width (approximately half the radius of the substrate processing region PR) in the radial direction based on the center CA of the substrate processing region PR.

[0039] 2, the third region R3 is densely hatched. The third region R3 is an annular region adjacent to the second region R2 and surrounding the second region R2, and includes the outer peripheral edge of the substrate processing region PR. The third region R3 has a constant width (approximately 5 mm) in the radial direction based on the center CA of the substrate processing region PR.

[0040] Here, imaginary circles are defined in each of the above regions (R1, R2, R3). First, in the first region R1, a virtual circle having a radius approximately half the radius of the first region R1, based on the center CA of the substrate processing region PR, is defined as a first imaginary circle VC1. In the second region R2, a virtual circle having a radius approximately half the radius of the substrate processing region PR, based on the center CA of the substrate processing region PR, is defined as a second imaginary circle VC2. Furthermore, in the third region R3, a virtual circle having a radius slightly smaller than the radius of the substrate processing region PR, based on the center CA of the substrate processing region PR, is defined as a third imaginary circle VC3. In the radial direction based on the center CA of the substrate processing region PR, the distance between the third imaginary circle VC3 and the outer circumferential edge of the substrate processing region PR is approximately 3 mm or more and 5 mm or less.

[0041] In the heat treatment apparatus 100 according to this embodiment, some of the plurality of support members 13 are arranged on a first imaginary circle VC1 at equal angular intervals with respect to the center CA of the substrate processing region PR. More specifically, in the heat treatment apparatus 100 of this example, three of the 21 support members 13 are arranged on the first imaginary circle VC1 at 120° intervals with respect to the center CA of the substrate processing region PR.

[0042] Furthermore, some of the support members 13 are arranged on a second imaginary circle VC2 at equal angular intervals with respect to the center CA of the substrate processing region PR. More specifically, in the heat treatment apparatus 100 of this example, six of the twenty-one support members 13 are arranged on the second imaginary circle VC2 at 60° intervals with respect to the center CA of the substrate processing region PR.

[0043] Furthermore, the remaining support members 13 are arranged on a third imaginary circle VC3 at equal angular intervals with respect to the center CA of the substrate processing region PR. More specifically, in the heat treatment apparatus 100 of this example, 12 of the 21 support members 13 are arranged on the third imaginary circle VC3 at 30° intervals with respect to the center CA of the substrate processing region PR.

[0044] In the arrangement of the above-mentioned multiple support members 13, the number of support members 13 arranged per unit length of the first imaginary circle VC1 and the number of support members 13 arranged per unit length of the third imaginary circle VC3 are greater than the number of support members 13 arranged per unit length of the second imaginary circle VC2.

[0045] In other words, the linear density of the support members 13 on the first imaginary circle VC1 and the linear density of the support members 13 on the third imaginary circle VC3 are greater than the linear density of the support members 13 on the second imaginary circle VC2. This reduces the contact of the center of the substrate W with the processing surface 11 when the substrate W has local distortion at the center and its vicinity, and is placed on a plurality of support members 13. Furthermore, when the substrate W has local distortion at the outer circumferential edge and its vicinity, and is placed on a plurality of support members 13, the contact of the outer circumferential edge of the substrate W with the processing surface 11 is reduced.

[0046] Furthermore, the above-described arrangement of the plurality of support members 13 prevents an excessive number of support members 13 from being provided in the second region R2 corresponding to the portion of the substrate W that is considered to be relatively less susceptible to warping (deformation). Therefore, the occurrence of defects on the underside of the substrate W due to contact with the numerous support members 13 caused by an excessive number of support members 13 being arranged on the substrate processing region PR is prevented.

[0047] Note that a substrate W with low rigidity is prone to deflection due to its own weight. Therefore, it is preferable to determine the radius of the second imaginary circle VC2 and the number of support members 13 arranged on the second imaginary circle VC2 based on experiments, simulations, etc., so that the substrate W does not come into contact with the processing surface 11 due to distortion caused by deflection due to its own weight.

[0048] <3> Arrangement of multiple temperature sensors TS1 As described above, even when the arrangement of the multiple support members 13 is determined so as to reduce contact between the substrate W and the processing surface 11, there is a possibility that part of the substrate W may come into contact with the processing surface 11. As explained in the summary of the invention, if a substrate W that has not been subjected to the desired heat treatment due to contact with the processing surface 11 is introduced into a subsequent manufacturing line as a substrate W that has been subjected to the desired heat treatment, the yield of semiconductor products will decrease.

[0049] A difference occurs in the temperature distribution of the processing surface 11 between a case where the substrate W does not come into contact with the processing surface 11 when the substrate W is placed and a case where the substrate W comes into contact with the processing surface 11 when the substrate W is placed. Therefore, in the heat treatment apparatus 100 according to this embodiment, it is preferable to arrange multiple temperature sensors TS1 in the plate member 10 so that contact between the substrate W and the processing surface 11 can be detected with high accuracy. In order to find a preferable arrangement of the multiple temperature sensors TS1, the inventors conducted a confirmation test using a test plate member provided with multiple support members to confirm the temperature change of the plate member at the start of heat treatment.

[0050] Specifically, the inventors set a portion of the treatment surface of a test plate member as the observation point. The inventors also maintained the temperature of the test plate member at 110°C using a heating element. In this state, the inventors placed a distortion-free first substrate on multiple support members without contacting the test plate member, and obtained the temperature change at the observation point for a predetermined period of time, including the time when the first substrate was placed.

[0051] Next, the inventors removed the first substrate from the test plate member and maintained the temperature of the test plate member at 110°C again using a heating element. In this state, the inventors placed a second substrate having distortion on multiple support members. At this time, the distortion portion of the second substrate was in contact with the test plate member near the observation point. The inventors also obtained temperature changes at the observation point for a predetermined period, including the time when the second substrate was placed.

[0052] Next, the inventors removed the second substrate from the test plate member and used a heating element to maintain the temperature of the test plate member at 110°C again. In this state, the inventors placed a third substrate, which had a different distortion from the second substrate, on the multiple support members. At this time, the distorted portion of the third substrate was in contact with the test plate member at a position slightly separated from the observation point. The inventors also obtained temperature changes at the observation point for a predetermined period, including the time when the third substrate was placed.

[0053] Fig. 3 shows the results of the confirmation test for the first substrate and the second substrate. Fig. 4 shows the results of the confirmation test for the first substrate and the third substrate. Figs. 3 and 4 show the results of each confirmation test in the form of a graph. In the graphs of Figs. 3 and 4, the vertical axis represents the temperature of the observation point on the test plate member, and the horizontal axis represents time. 0 sec on the time axis represents the time when each substrate was placed on the multiple support members.

[0054] 3 and 4, the temperature change at the observation point when the first substrate is placed on the multiple support members is shown by a solid line. In Fig. 3, the temperature change at the observation point when the second substrate is placed on the multiple support members is shown by a dashed line. In Fig. 4, the temperature change at the observation point when the third substrate is placed on the multiple support members is shown by a dashed line.

[0055] As described above, the first substrate is placed on the support members without contacting the test plate member. Therefore, the temperature change at the observation point when the first substrate is placed is the ideal temperature change at the observation point when normal heating is performed. As shown by the solid lines in Figures 3 and 4, when normal heating is performed, the temperature at the observation point drops by approximately 1.1°C from 110°C within 10 seconds of placing the substrate, and then gradually rises to approximately 110°C within approximately 60 seconds of placing the substrate.

[0056] In contrast, as shown by the dotted line in Figure 3, when the second substrate and the test plate member come into contact near the observation point, the temperature at the observation point drops from approximately 110°C to approximately 1.7°C within 10 seconds of the substrate being placed, and then gradually rises to approximately 110°C within approximately 60 seconds of the substrate being placed.

[0057] Furthermore, as shown by the dotted line in Figure 4, when the third substrate and the test plate member come into contact at a position slightly away from the observation point, the temperature at the observation point drops by about 1.4°C from approximately 110°C within 10 seconds of placing the substrate, and then gradually rises to about 110°C within approximately 60 seconds of placing the substrate.

[0058] As a result, it was confirmed that the temperature of each part of the test plate member, which was maintained at the processing temperature, dropped relatively significantly over a certain period of time (approximately 20 seconds) from the time the substrate was placed. It was also confirmed that the temperature of each part of the test plate member was more likely to change the closer it was to the part in contact with the substrate, and that this deviated significantly from the temperature change that would occur if normal heating processing were performed. Furthermore, it was confirmed that the temperature of each part of the test plate member, the farther it was from the part in contact with the substrate, the closer it approached the temperature change that would occur if normal heating processing were performed.

[0059] Based on the above-mentioned confirmation test results and study results, the inventors have concluded that it is preferable to arrange a plurality of temperature sensors TS1 at a portion of the processing surface 11 that is likely to come into contact with the substrate W or in the vicinity thereof.

[0060] 2, in the substrate processing region PR of the plate member 10, the plurality of support members 13 are arranged at a relatively high density in the first region R1 and the third region R3. In contrast, the density of the plurality of support members 13 is low in the second region R2. Therefore, distortion occurs in the substrate W due to bending of the substrate W due to its own weight, and the distorted portion of the substrate W may come into contact with the processing surface 11.

[0061] Therefore, in this embodiment, when a plurality of imaginary straight lines VL are defined that extend radially from the center CA of the substrate processing region PR toward the plurality of support members 13 on the second imaginary circle VC2 in a plan view, the plurality of temperature sensors TS1 are arranged so that one temperature sensor TS1 is located between every two adjacent imaginary straight lines VL. In Fig. 2, the plurality of temperature sensors TS1 are indicated by dashed-dotted square marks to make the arrangement of the plurality of temperature sensors TS1 easier to understand.

[0062] According to the above arrangement, when a part of the substrate W contacts the processing surface 11 between two adjacent imaginary straight lines VL, a temperature change of the processing surface 11 caused by the contact of the substrate W is directly acquired by one of the temperature sensors TS1, thereby improving the accuracy of determining whether the substrate W is in contact with the processing surface 11.

[0063] In the above configuration, it is preferable that one temperature sensor TS1 arranged between two adjacent virtual straight lines VL is arranged on a straight line that divides the angle formed by the two virtual straight lines VL into two.

[0064] 3. Determining whether the substrate W is in contact with the processing surface 11 <1> Temperature changes acquired by multiple temperature sensors TS1 2, the temperature sensor TS1 located at the top of the substrate processing region PR will be referred to as the first sensor. The temperature sensors TS1 arranged clockwise from the first sensor around the center CA of the substrate processing region PR in a plan view will be referred to as the second sensor, third sensor, fourth sensor, fifth sensor, and sixth sensor, respectively.

[0065] Fig. 5 is a diagram showing an example of estimated temperature changes acquired by the first to sixth sensors when normal heating is performed. In Fig. 5, six graphs are shown from the top to the bottom, showing examples of estimated temperature changes acquired by the first to sixth sensors when normal heating is performed. In each graph, the vertical axis represents the temperature of the portion of the processing surface 11 where the sensor corresponding to the graph is located, and the horizontal axis represents time.

[0066] Assume that the substrate W is placed on the plurality of support members 13 at time t1, with the temperature of the processing surface 11 maintained at processing temperature α. When normal heating processing is performed, the temperature changes acquired by the first to sixth sensors are considered to be roughly consistent, as shown in the six graphs in Fig. 5. In the example of Fig. 5, the temperature of each part of the processing surface 11 drops sharply from processing temperature α to temperature β from time t1 to time t2, and then rises gradually from temperature β to processing temperature α from time t2 to time t3.

[0067] Fig. 6 is a diagram showing an example of estimated temperature changes acquired by the first to sixth sensors when a portion of the substrate W comes into contact with the processing surface 11. In Fig. 6, six graphs are shown from the top to the bottom, showing examples of estimated temperature changes acquired by the first to sixth sensors when a portion of the substrate W comes into contact with the processing surface 11. As in the example of Fig. 5, in each graph, the vertical axis represents the temperature of the portion of the processing surface 11 where the sensor corresponding to the graph is located, and the horizontal axis represents time.

[0068] With the temperature of the processing surface 11 maintained at processing temperature α, the substrate W is placed on the plurality of support members 13 at time t1. Furthermore, when the substrate W is placed, a part of the substrate W comes into contact with the processing surface 11 at a position overlapping the third sensor.

[0069] In this case, large variations occur among the temperature changes corresponding to the first through sixth sensors. Specifically, from time t1 to time t2, the temperature detected by the third sensor drops significantly more than the temperatures detected by the other sensors. The temperatures detected by the second and fourth sensors adjacent to the third sensor also drop somewhat more than the temperatures detected by the other sensors. Meanwhile, the temperatures detected by the first, fifth, and sixth sensors, which are positioned relatively far away from the third sensor, drop by the same level as during normal heating.

[0070] Taking into consideration the temperature changes at each part of the processing surface 11 estimated as described above, whether or not the substrate W is in contact with the processing surface 11 is determined by, for example, the first and second determination methods described below.

[0071] <2> First judgment method As described above, when normal heating processing is performed, the temperature changes of the processing surface 11 acquired by the plurality of temperature sensors TS1 become approximately the same until a certain time (for example, 10 or 20 seconds) has elapsed since the substrate W was placed.

[0072] Therefore, before the heat treatment of the actual substrate W, a sample substrate of the same type as the substrate W is prepared. It is preferable to select a substrate that has almost no distortion as this sample substrate.

[0073] Next, the prepared sample substrate is placed on the plurality of support members 13 and subjected to a heat treatment. At this time, one of the plurality of temperature sensors TS1 is used to acquire the temperature change of the processing surface 11 until a certain time has passed without the sample substrate coming into contact with the processing surface 11. Then, based on the acquired temperature change, a first threshold value corresponding to the amount of temperature change of the processing surface 11 until the certain time has passed from the time the sample substrate is placed is determined.

[0074] The first threshold value is set to a temperature change amount slightly larger than that of the sample substrate, for example. Thereafter, during the actual heating process of the substrate W, it is determined whether the actual temperature change amount detected by each temperature sensor TS1 during a certain time period from the time the substrate W is placed is larger than the first threshold value. If the actual temperature change amount is larger than the first threshold value, it is determined that a downwardly distorted portion of the substrate W is in contact with the processing surface 11.

[0075] According to the above-described first determination method, it is possible to determine whether or not the substrate W is in contact with the processing surface 11 without requiring any complicated processing. When a plurality of substrates W are successively heat-processed in the heat processing apparatus 100, another substrate W that has been heat-processed before the heat processing of one substrate W may be regarded as a sample substrate. In this case, the first threshold value to be used during the heat processing of one substrate W is determined based on the temperature change acquired during the heat processing of the other substrate W regarded as the sample substrate.

[0076] <3> Second Judgment Method As described above, when normal heating processing is performed, the temperature changes of the processing surface 11 acquired by the multiple temperature sensors TS1 are approximately the same until a certain time (e.g., 10 or 20 seconds) has elapsed since the substrate W was placed. In contrast, when a portion of the substrate W comes into contact with the processing surface 11, there is a large variation among the multiple temperature changes acquired by the multiple temperature sensors TS1, as shown in the example of FIG.

[0077] Therefore, in the second determination method, a second threshold value is determined for determining whether the variation in the multiple temperatures detected by the multiple temperature sensors TS1 from the time the substrate W is placed until a certain time has elapsed is within a range corresponding to normal heating processing. The second threshold value is determined to be the maximum value that can guarantee normal heating processing, for example, based on an experiment using a sample substrate. Then, during the actual heating processing of the substrate W, it is determined whether the magnitude of the variation in the multiple temperatures detected by the multiple temperature sensors TS1 from the time the substrate W is placed until a certain time has elapsed is greater than the second threshold value. If the magnitude of the variation in the multiple temperatures detected by the multiple temperature sensors TS1 is greater than the second threshold value, it is determined that a downwardly distorted portion of the substrate W is in contact with the processing surface 11.

[0078] According to the second determination method described above, it becomes possible to appropriately determine whether or not the substrate W is in contact with the processing surface 11, regardless of the processing temperature. When a plurality of substrates W are successively heat-processed in the heat processing apparatus 100, another substrate W that has been heat-processed before the heat processing of one substrate W may be regarded as a sample substrate. In this case, the second threshold value to be used during the heat processing of one substrate W is determined based on the variations in the plurality of temperatures detected during the heat processing of the other substrate W regarded as the sample substrate.

[0079] 4. Control system of the heat treatment device 100 The control device 90 in Fig. 1 includes a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), and a storage device. The RAM is used as a working area for the CPU. The ROM stores system programs. The storage device stores a heat processing program for performing heat processing on the substrate W, and a contact determination program for determining whether the substrate W is in contact with the processing surface 11.

[0080] Here, the contact determination program may be provided in a state stored in a recording medium such as a CD-ROM 909, and may be installed in the ROM or storage device of the control device 90. Alternatively, the contact determination program may be distributed from a server external to the heat treatment device 100 via a communication network, and may be installed in the ROM or storage device.

[0081] 1, the control device 90 includes functional units for controlling the operation of each unit of the heat treatment device 100 and for performing predetermined processes, such as a temperature control unit 91, an elevation control unit 92, a temperature acquisition unit 93, a temperature information setting unit 94, a temperature information storage unit 95, and a contact determination unit 96. The functional units of the control device 90 are realized by a CPU executing a heat treatment program and a contact determination program stored in a storage device on a RAM. Some or all of the functional units of the control device 90 may be realized by hardware such as electronic circuits.

[0082] The lifting control unit 92 controls the lifting device 40 so that the plurality of lifting pins 41 move from an upper position to a lower position when the substrate W carried in from outside the heat treatment device 100 is placed on the processing surface 11 of the plate member 10. The lifting control unit 92 also controls the lifting device 40 so that the plurality of lifting pins 41 move from a lower position to an upper position when the substrate W placed on the processing surface 11 is transferred to a robot outside the heat treatment device 100.

[0083] The temperature acquisition unit 93 acquires the temperatures of the portions where the temperature sensors TS1 and TS2 are provided (the portions of the processing surface 11) based on the detection values ​​output from the plurality of temperature sensors TS1 and TS2. The temperature acquisition unit 93 also provides the plurality of temperatures acquired based on the outputs of the plurality of temperature sensors TS1 to the contact determination unit 96, and provides the temperature acquired based on the output of the temperature sensor TS2 to the temperature control unit 91.

[0084] The temperature control unit 91 performs feedback control of the heat generating drive circuit 21 based on the temperature given by the temperature acquisition unit 93 so that the processing surface 11 is maintained at a predetermined processing temperature.

[0085] By operating the operation unit 98, the user can input information for determining whether or not the substrate W and the processing surface 11 are in contact with each other as reference temperature information. The reference temperature information may be the first threshold value of the first determination method described above, or the second threshold value of the second determination method described above. When the reference temperature information is input, the temperature information setting unit 94 accepts the input reference temperature information. The accepted reference temperature information is stored in the temperature information storage unit 95.

[0086] For example, during the heating process of the sample substrate, a plurality of temperatures acquired by a plurality of temperature sensors TS1 may be provided from the temperature acquisition unit 93 to the temperature information setting unit 94. In this case, the temperature information setting unit 94 may automatically generate reference temperature information (for example, a first threshold value or a second threshold value) based on the plurality of temperatures provided from the temperature acquisition unit 93.

[0087] When the substrate W is subjected to heat treatment, the contact determination unit 96 determines whether or not a downwardly distorted portion of the substrate W is in contact with the processing surface 11, based on the reference temperature information stored in the temperature information storage unit 95 and a plurality of temperatures provided by the temperature acquisition unit 93. The contact determination unit 96 also outputs the determination result to the presentation device 99.

[0088] The presentation device 99 includes a display and an audio output device as described above. As a result, the display displays the determination result given by the contact determination unit 96. Furthermore, the audio output device outputs the determination result given by the contact determination unit 96 as audio. This allows the user to easily understand whether the heat treatment is being performed properly. Furthermore, if contact occurs between the substrate W and the treatment surface 11, the user can immediately understand that a processing defect has occurred.

[0089] 5.Collision detection processing In the control device 90, the CPU executes a contact determination program stored in the storage device to perform a contact determination process for determining whether or not the substrate W is in contact with the processing surface 11. FIG. 7 is a flowchart showing an example of the contact determination process. The contact determination process is started when the power supply to the heat treatment device 100 is turned on. In this example, it is assumed that no reference temperature information is stored in the temperature information storage unit 95 of FIG. 1 at the start of the contact determination process. It is also assumed that the control device 90 has a built-in timer.

[0090] 7, when the contact determination process is started, the temperature information setting unit 94 determines whether or not reference temperature information has been input based on the user's operation of the operation unit 98 (step S11). In this example, the reference temperature information is information that is determined in advance by the user by conducting various experiments using a sample substrate or the like.

[0091] If the reference temperature information is not input, the process of step S11 is repeated. On the other hand, if the reference temperature information is input, the temperature information setting unit 94 accepts the input reference temperature information and stores the accepted reference temperature information in the temperature information storage unit 95 (step S12).

[0092] Next, similar to the process of step S11, the temperature information setting unit 94 determines whether or not reference temperature information has been input based on the user's operation of the operation unit 98 (step S13). If the reference temperature information has been input, the process returns to step S12. In this case, in step S12, the reference temperature information previously stored in the temperature information storage unit 95 is updated with the newly input reference temperature information.

[0093] If the reference temperature information is not input in step S13, the temperature acquisition unit 93 determines whether or not a substrate W has been placed on the processing surface 11 (step S14). The processing of step S14 can be performed based on, for example, the control timing of the lifting device 40 when the substrate W is placed on the processing surface 11.

[0094] If a substrate W is not placed on the processing surface 11, the process returns to step S13. On the other hand, if a substrate W is placed on the processing surface 11, the temperature acquisition unit 93 resets the timer of the control device 90 and starts measuring time with the timer (step S15). In addition, the temperature acquisition unit 93 starts acquiring temperature changes at multiple parts of the processing surface 11 based on detection values ​​output from the multiple temperature sensors TS1 (step S16).

[0095] Next, the temperature acquisition unit 93 determines whether a predetermined fixed time has elapsed since the timer started measuring time (step S17). The fixed time is predetermined by the user and may be, for example, 10 seconds, 20 seconds, or 60 seconds. If the fixed time has not elapsed, the process of step S17 is repeated. On the other hand, if the fixed time has elapsed, the contact determination unit 96 determines whether a downwardly distorted portion of the substrate W is in contact with the processing surface 11 based on the reference temperature information and the multiple temperature changes acquired by the temperature acquisition unit 93 (step S18). The contact determination unit 96 also outputs the determination result to the presentation device 99 (step S19). Thereafter, the process returns to step S13.

[0096] In the above series of processes, if the contact determination unit 96 determines in step S18 that the substrate W is in contact with the processing surface 11, it may stop the operation of the heat treatment apparatus 100. Alternatively, the contact determination unit 96 may use, for example, a printing device to mark the substrate W that has come into contact with the processing surface 11, indicating that a processing defect has occurred. In these cases, the user can quickly identify the substrate W that has experienced a processing defect and remove it from the production line.

[0097] Furthermore, in this example, the reference temperature information is stored in the temperature information storage unit 95 based on input by the user, but the present invention is not limited to this. The temperature acquisition unit 93 may acquire temperature changes at multiple locations on the processing surface 11 based on outputs from multiple temperature sensors TS1 when the sample substrate is heated. The temperature information setting unit 94 may generate reference temperature information based on the temperature changes at multiple locations on the processing surface 11 acquired when the sample substrate is heated, and store the reference temperature information in the temperature information storage unit 95.

[0098] Furthermore, when multiple substrates W are successively heated in the heat treatment apparatus 100, the other substrates W that were heated before the heating treatment of one substrate W may be regarded as sample substrates, and reference temperature information may be generated based on multiple temperature changes acquired during the heating treatment of the other substrates W.

[0099] 6.Effects In the heat treatment apparatus 100, a plurality of support members 13 are provided on the treatment surface 11 of the plate member 10. With the temperature of the treatment surface 11 adjusted to a treatment temperature, the substrate W is placed on the plurality of support members 13. Thereby, the substrate W is subjected to a heat treatment.

[0100] When a substrate W is placed on multiple support members 13 with the temperature of the processing surface 11 adjusted to the processing temperature, multiple temperature sensors TS1 acquire multiple temperature changes in multiple parts of the processing surface 11 from the time the substrate W is placed until a certain period of time has elapsed.

[0101] Whether or not the substrate W is in contact with the processing surface 11 is determined based on the acquired temperature changes and the reference temperature information stored in the temperature information storage unit 95. This makes it possible to quickly determine whether or not a heat processing defect has occurred due to a downwardly warped portion of the substrate W coming into contact with the processing surface 11 after the heating processing of the substrate W has started.

[0102] In this case, the substrates W that have not been subjected to the desired heat treatment can be removed from the manufacturing line at an appropriate time, thereby improving the manufacturing yield of semiconductor products using the heat-treated substrates W.

[0103] 7. Other Embodiments (a) In the heat treatment apparatus 100 according to the above embodiment, a plurality of temperature sensors TS1 are provided in the portion of the plate member 10 that overlaps the second region R2. Furthermore, no temperature sensors TS1 are provided in the portions of the plate member 10 that overlap the first region R1 and the third region R3. However, the present invention is not limited to this.

[0104] The heat treatment apparatus 100 may have the following configuration. Fig. 8 is an enlarged plan view of a plate member 10 according to another embodiment. In the plate member 10 of Fig. 8, six temperature sensors TS1 are provided so as to overlap the second region R2, and one temperature sensor TS1 is further provided so as to overlap the first region R1. More specifically, one temperature sensor TS1 is provided so as to overlap the center CA of the substrate processing region PR (see the hollow arrow in Fig. 8).

[0105] According to the above configuration, when a substrate W having a bulge or depression in the central portion is placed on the plurality of support members 13 and the center of the substrate W contacts the center CA of the substrate processing region PR, the temperature change at the center CA is directly acquired by the temperature sensor TS1. This improves the accuracy of determining whether or not a downwardly distorted portion of the substrate W is in contact with the processing surface 11.

[0106] The heat treatment apparatus 100 may have the following configuration. Fig. 9 is an enlarged plan view of a plate member 10 according to yet another embodiment. In the plate member 10 of Fig. 9, six temperature sensors TS1 are provided so as to overlap the second region R2, and twelve temperature sensors TS1 are further provided so as to overlap the third region R3. More specifically, in plan view, one temperature sensor TS1 is provided between each two support members 13 adjacent to each other on a third imaginary circle VC3 (see the hollow arrows in Fig. 9).

[0107] When a substrate W having warpage (deformation) at and near its outer circumferential edge is placed on the support members 13, the outer circumferential edge of the substrate W may come into contact with the vicinity of the outer circumferential edge of the substrate processing region PR. Even in such a case, with the above-described configuration, the temperature change of the processing surface 11 caused by the contact of the substrate W is directly detected by one of the temperature sensors TS1 arranged in the third region R3. This improves the accuracy of determining whether a downwardly warped portion of the substrate W is in contact with the processing surface 11. Note that in the configuration of FIG. 9, an additional temperature sensor TS1 may be further provided so as to overlap the center CA of the substrate processing region PR.

[0108] (b) In the heat treatment apparatus 100 according to the above embodiment, a plurality of temperature sensors TS1 are provided inside the plate member 10 to detect the temperatures of a plurality of portions of the treatment surface 11, but the present invention is not limited to this. The heat treatment apparatus 100 may be provided with optical fibers instead of the plurality of temperature sensors TS1.

[0109] In this case, the optical fiber is placed on the processing surface 11 so as to pass between the multiple support members 13. In this state, light is incident on one end of the optical fiber. This makes it possible to detect the temperature of each part on the processing surface 11 based on the intensity of scattered light emitted from the other end of the optical fiber.

[0110] (c) In the above embodiment, one temperature sensor TS2 is provided on the plate member 10 to control the driving state of the heating element 20, but the present invention is not limited to this. The plate member 10 may be provided with a plurality of individually controllable heating elements 20 and a plurality of temperature sensors TS2 corresponding to each heating element 20. In this case, the temperature of the processing surface 11 of the plate member 10 can be divided into a plurality of regions and controlled.

[0111] (d) In the above embodiment, a plurality of temperature sensors TS1 for determining whether or not the substrate W is in contact with the processing surface 11 and a temperature sensor TS2 for controlling the driving state of the heating element 20 are individually provided on the plate member 10. However, the present invention is not limited to this. At least some of the plurality of temperature sensors TS1 may be used as the temperature sensor TS2 for controlling the driving state of the heating element 20. Furthermore, the temperature sensor TS2 for controlling the driving state of the heating element 20 may be used as the temperature sensor TS1 for determining whether or not the substrate W is in contact with the processing surface 11.

[0112] (d) In the heat treatment apparatus 100 according to the above embodiment, the substrate W to be heat-treated is a circular substrate, but the present invention is not limited to this. The substrate W to be heat-treated is not limited to a circular shape, and may also have a rectangular shape. In this case, a rectangular substrate processing region PR is defined on the processing surface 11 of the plate member 10. Furthermore, a plurality of guide members 19 are provided on the processing surface 11 so as to surround the substrate processing region PR. Furthermore, a plurality of support members 13 are distributed within the substrate processing region PR.

[0113] (e) In the heat treatment apparatus 100 according to the above embodiment, the substrate W to be heat-treated has an outer diameter of 200 mm, but the outer diameter of the substrate W is not limited to 200 mm. A substrate W having an outer diameter other than 200 mm, such as 300 mm or 150 mm, may also be heat-treated.

[0114] Furthermore, the substrate W has a thickness of less than 775 μm, but may have a thickness of 775 μm or more. Furthermore, the substrate W is made of silicon or silicon carbide, but may be made of a material other than silicon or silicon carbide (e.g., gallium nitride, etc.).

[0115] (f) Although the heat treatment apparatus 100 according to the above embodiment performs a heating process on the substrate W, the present invention is not limited to this. The heat treatment apparatus 100 may be configured to be able to perform a cooling process on the substrate W as an example of a heat treatment. In this case, for example, a cooling element is provided on the mounting surface 12 of the plate member 10 in place of the heating element 20. The cooling element may be formed of a Peltier element. Alternatively, the heat treatment apparatus 100 may be configured to be able to selectively perform a heating process and a cooling process on the substrate W.

[0116] (g) In the above embodiment, the multiple temperature sensors TS1 are arranged so that one temperature sensor TS1 is located between each two adjacent imaginary lines VL, but the present invention is not limited to this. Two or more temperature sensors TS1 may be provided between each two imaginary lines VL.

[0117] 8. Correspondence between each part of the embodiment and each element of the claims The following describes examples of correspondence between the elements of the claims and the elements of the embodiments. Various other elements having the configurations or functions described in the claims may also be used as the elements of the claims.

[0118] In the above-described embodiment, the heat treatment apparatus 100 is an example of a heat treatment apparatus, the processing surface 11 is an example of a processing surface, the plate member 10 is an example of a plate member, the plurality of support members 13 are an example of a plurality of support members, the heating element 20 and the heat generation drive circuit 21 are examples of a heat treatment section, the plurality of temperature sensors TS1 are an example of a temperature detection section, the lifting device 40 is an example of a loading device, the temperature information storage unit 95 is an example of a temperature information storage unit, and the contact determination unit 96 is an example of a contact determination unit.

[0119] Furthermore, the substrate processing region PR is an example of a substrate processing region, the first region R1 is an example of a first region, the second region R2 is an example of a second region, the third region R3 is an example of a third region, the center CA of the substrate processing region PR is an example of a center of the substrate processing region, the first virtual circle VC1 is an example of a first virtual circle, the second virtual circle VC2 is an example of a second virtual circle, and the third virtual circle VC3 is an example of a third virtual circle.

[0120] Furthermore, the multiple support members 13 arranged in the first region R1 are an example of multiple first support members, the multiple support members 13 arranged in the second region R2 are an example of multiple second support members, the multiple support members 13 arranged in the third region R3 are an example of multiple third support members, and the multiple temperature sensors TS1 are an example of multiple temperature sensors.

[0121] Furthermore, the temperature sensor TS1 overlapping the center CA of the substrate processing area PR is an example of a central temperature sensor, the multiple temperature sensors TS1 overlapping the second area R2 of the substrate processing area PR are an example of multiple intermediate temperature sensors, the multiple temperature sensors TS1 overlapping the third area R3 of the substrate processing area PR are an example of multiple peripheral temperature sensors, the first threshold value is an example of a first reference value, and the second threshold value is an example of a second reference value.

[0122] 9. Summary of the embodiment (Item 1) The heat treatment device according to item 1 is A heat treatment apparatus for performing heat treatment on a substrate, a plate member having an upwardly facing processing surface; a plurality of support members provided on the processing surface so as to be able to support the lower surface of the substrate; a heat treatment section for performing heat treatment on the substrate supported by the plurality of support members on the processing surface by adjusting the temperature of the processing surface to a predetermined processing temperature; a temperature detection unit that detects the temperature of a portion of the processing surface where the plurality of support members are not provided; a mounting device that mounts the substrate on the plurality of support members; a temperature information storage unit that stores, as reference temperature information, information about temperature changes of the processing surface from the time when sample substrates of the same type as the substrate are placed on the plurality of support members by the mounting device, until a certain period of time has elapsed without the sample substrate coming into contact with the processing surface, while the temperature of the processing surface is adjusted to the processing temperature; When the substrate is placed on the plurality of support members by the placement device with the temperature of the processing surface adjusted to the processing temperature, the temperature change of the processing surface from the time the substrate is placed until the specified time has elapsed is acquired based on the detection result of the temperature detection unit, and the contact determination unit determines whether or not a portion of the substrate that is distorted downward is in contact with the processing surface based on the acquired temperature change of the processing surface and the reference temperature information.

[0123] In the heat treatment apparatus, a plurality of support members are provided on a treatment surface of a plate member, and substrates are placed on the support members while the temperature of the treatment surface is adjusted to a treatment temperature, whereby the substrates are subjected to heat treatment.

[0124] In the heat treatment apparatus, when a substrate is placed on a plurality of support members with the temperature of the treatment surface adjusted to the treatment temperature, the temperature change of the treatment surface from the time the substrate is placed until a certain time has elapsed is acquired based on the detection results of the temperature detection unit. Based on the acquired temperature change of the treatment surface and the reference temperature information stored in the temperature information storage unit, it is determined whether a downwardly distorted portion of the substrate is in contact with the treatment surface. This makes it possible to quickly determine whether a heat treatment defect has occurred due to the substrate contacting the treatment surface after the heat treatment of the substrate has begun.

[0125] In this case, substrates that have not undergone the desired heat treatment can be removed from the manufacturing line at an appropriate time, thereby improving the manufacturing yield of semiconductor products that use heat-treated substrates.

[0126] (Item 2) In the heat treatment device according to item 1, the substrate is a circular substrate, the processing surface has a circular shape corresponding to the substrate in a plan view, a circular substrate processing area is defined on the processing surface, in which the substrate is to be placed during thermal processing of the substrate; The substrate processing region includes: When the substrate is placed in the substrate processing region, a circular first region overlaps with a portion including a center of the substrate; a second region having an annular shape adjacent to the first region and surrounding the first region in a plan view; a third region having an annular shape that is adjacent to the second region in a plan view, surrounds the second region, and includes an outer peripheral edge of the substrate processing region; The plurality of support members may be distributed on the processing surface such that at least one support member is located in each of the first region, the second region, and the third region.

[0127] In this case, the distance between the portions of the substrate supported by the support members can be made shorter than when the support members support only the center of the lower surface of the substrate and the outer peripheral edge of the substrate, thereby reducing the contact of the substrate with the processing surface due to distortion caused by bending of the substrate due to its own weight between the support members.

[0128] (Item 3) In the heat treatment device according to item 2, defining a first virtual circle in the first region of the substrate processing region, the first virtual circle being based on a center of the substrate processing region in a plan view; defining a second virtual circle in the second region of the substrate processing region, the second virtual circle being based on a center of the substrate processing region in a plan view; In the third region of the substrate processing region, when a third virtual circle is defined based on the center of the substrate processing region in a plan view, The plurality of support members include: a plurality of first support members arranged on the first virtual circle at predetermined angular intervals with the center of the substrate processing region as a reference; a plurality of second support members arranged on the second imaginary circle at predetermined angular intervals with respect to the center of the substrate processing region; The substrate processing apparatus may further include a plurality of third support members arranged on the third imaginary circle at predetermined angular intervals with the center of the substrate processing region as a reference.

[0129] In this case, the entire lower surface of the substrate can be supported, which reduces the possibility of the substrate coming into contact with the processing surface due to distortion caused by bending of the substrate due to its own weight between the multiple support members.

[0130] (Item 4) In the heat treatment device according to item 3, The number of the plurality of first support members arranged per unit length of the first virtual circle and the number of the plurality of third support members arranged per unit length of the third virtual circle may be greater than the number of the plurality of second support members arranged per unit length of the second virtual circle.

[0131] The present inventors have conducted various experiments and studies on various distortions that occur in circular substrates. As a result, the present inventors have found that substrates with low rigidity tend to warp (deform) so that the center and its surrounding areas bulge or dent in a direction perpendicular to the substrate. The present inventors have also found that substrates with low rigidity tend to warp (deform) locally at the outer periphery and its surrounding areas.

[0132] According to the above configuration, the linear density of the first support members in the first imaginary circle and the linear density of the third support members in the third imaginary circle are greater than the linear density of the second support members in the second imaginary circle. This reduces the possibility of the center of a substrate having local distortion at its center and its vicinity being placed on multiple support members. Furthermore, when a substrate having local distortion at its outer periphery and its vicinity being placed on multiple support members, it reduces the possibility of the outer periphery of the substrate being placed on the support members.

[0133] Furthermore, the above configuration prevents an excessive number of second support members from being provided in the second region corresponding to a portion of the substrate that is relatively less likely to be distorted, thereby preventing defects on the underside of the substrate caused by contact with a large number of support members due to an excessive number of support members being disposed in the substrate processing region.

[0134] (Item 5) In the heat treatment device according to any one of items 2 to 4, the temperature detection unit includes a plurality of temperature sensors that detect temperatures of a plurality of portions of the processing surface, The plurality of temperature sensors may include a central temperature sensor that overlaps the center of the substrate processing region in a plan view.

[0135] The present inventors have conducted various experiments and studies on various distortions that occur in circular substrates, and as a result, have found that a substrate with low rigidity tends to warp (deform) so that a portion including the center bulges or dents in a direction perpendicular to the substrate.

[0136] According to the above configuration, the center temperature sensor is located at the center of the substrate processing area. Therefore, when a substrate having a bulge or depression in its central portion is placed on the support members and the center of the substrate is in contact with or near the center of the processing surface, the temperature change of the processing surface due to the substrate contact is directly detected by the center temperature sensor. This improves the accuracy of determining whether the substrate is in contact with the processing surface.

[0137] (Item 6) In the heat treatment device according to any one of items 2 to 4, the temperature detection unit includes a plurality of temperature sensors that detect temperatures of a plurality of portions of the processing surface, the plurality of temperature sensors include a plurality of intermediate temperature sensors that overlap the second region in a plan view; When a plurality of virtual straight lines are defined that extend radially from the center of the substrate processing region toward the plurality of second support members in a plan view, The plurality of intermediate temperature sensors may be provided such that at least one intermediate temperature sensor is located between each two imaginary straight lines adjacent to each other around the center of the substrate processing region.

[0138] According to the above configuration, the multiple intermediate temperature sensors are positioned between two adjacent virtual lines in the second region. Therefore, when a portion of the substrate contacts the processing surface between the two adjacent virtual lines in the second region due to distortion caused by its own weight, the temperature change of the processing surface caused by the substrate contact is directly acquired by one of the intermediate temperature sensors. This improves the accuracy of determining whether the substrate is in contact with the processing surface.

[0139] (Item 7) In the heat treatment device according to item 3 or 4, the temperature detection unit includes a plurality of temperature sensors that detect temperatures of a plurality of portions of the processing surface, the plurality of temperature sensors include a plurality of peripheral temperature sensors that overlap the third region in a plan view, The plurality of peripheral temperature sensors may be provided such that at least one peripheral temperature sensor is located between each pair of third support members adjacent to each other on the third imaginary circle.

[0140] The present inventors have conducted various experiments and studies on various types of distortion that occur in circular substrates, and as a result, have found that substrates with low rigidity tend to warp (deform) locally at and near the outer periphery.

[0141] According to the above configuration, the plurality of peripheral temperature sensors are located near the outer peripheral edge of the substrate processing region. Therefore, when the outer peripheral edge of the substrate contacts the vicinity of the outer peripheral edge of the substrate processing region, a temperature change of the processing surface due to the substrate contact is directly detected by one of the plurality of peripheral temperature sensors. This improves the accuracy of determining whether the substrate is in contact with the processing surface.

[0142] (Item 8) In the heat treatment device according to any one of items 1 to 7, the reference temperature information is a first reference value corresponding to a temperature change amount of the processing surface from the time when the sample substrate is placed on the plurality of support members until a certain time has elapsed, The contact determination unit may determine that the substrate is in contact with the processing surface if the actual temperature change detected by the temperature detection unit between the time the substrate is placed and the time the certain period of time has elapsed is greater than the first reference value.

[0143] In this case, it is possible to determine whether or not the substrate is in contact with the processing surface without requiring any complicated processing.

[0144] (Item 9) In the heat treatment device according to any one of items 1 to 4, the temperature detection unit includes a plurality of temperature sensors that detect temperatures of a plurality of portions of the processing surface, the reference temperature information is a second reference value corresponding to the magnitude of variation in the temperatures detected by the temperature sensors during a period from when the sample substrate is placed on the support members until a certain time has elapsed, and The contact determination unit may determine that the substrate is in contact with the processing surface if the magnitude of variation in the temperatures detected by the temperature sensors between the time the substrate is placed and the time the certain period of time has elapsed is greater than the second reference value.

[0145] In this case, it is possible to appropriately determine whether the substrate is in contact with the processing surface regardless of the processing temperature.

[0146] (Item 10) The heat treatment method according to item 10 includes: A heat treatment method for performing heat treatment on a substrate using a heat treatment apparatus, comprising: The heat treatment device includes: a plate member having an upwardly facing processing surface; a plurality of support members provided on the processing surface so as to be able to support the lower surface of the substrate; The heat treatment method includes: storing, as reference temperature information, information regarding temperature changes of the processing surface from the time when a sample substrate of the same type as the substrate is placed on the plurality of support members until a certain time has passed without the sample substrate coming into contact with the processing surface, with the temperature of the processing surface adjusted to a predetermined processing temperature; After the storing step, placing the substrate on the plurality of support members in a state where the temperature of the processing surface is adjusted to a predetermined processing temperature; after the placing step, a step of adjusting the temperature of the processing surface to the processing temperature, thereby performing a heat treatment on the substrate supported by the plurality of support members on the processing surface; detecting a temperature of a portion of the processing surface where the plurality of support members are not provided by a temperature detection unit; When the substrate is placed on the plurality of support members with the temperature of the processing surface adjusted to the processing temperature, the temperature change of the processing surface from the time the substrate is placed until the certain time has elapsed is acquired based on the detection result of the temperature detection unit, and based on the acquired temperature change of the processing surface and the reference temperature information stored in the storing step, it is determined whether or not a portion of the substrate that is distorted downward is in contact with the processing surface.

[0147] In this heat treatment method, with the temperature of the treatment surface adjusted to a predetermined treatment temperature, information regarding the temperature change of the treatment surface from the time when a sample substrate of the same type as the substrate is placed on multiple support members until a certain period of time has passed without the sample substrate coming into contact with the treatment surface is stored as reference temperature information.

[0148] Then, the substrate is placed on the plurality of support members with the temperature of the processing surface adjusted to a predetermined processing temperature, and the temperature of the processing surface is adjusted to the processing temperature, thereby performing a heat treatment on the substrate.

[0149] As described above, when a substrate is placed on a plurality of support members with the temperature of the processing surface adjusted to the processing temperature, the temperature change of the processing surface from the time the substrate is placed until a certain time has elapsed is acquired based on the detection results of the temperature detection unit. Based on the acquired temperature change of the processing surface and the stored reference temperature information, it is determined whether or not a downwardly distorted portion of the substrate is in contact with the processing surface. This makes it possible to quickly determine whether or not a heat processing defect has occurred due to the substrate contacting the processing surface after heat processing of the substrate has begun.

[0150] In this case, substrates that have not undergone the desired heat treatment can be removed from the manufacturing line at an appropriate time, thereby improving the manufacturing yield of semiconductor products that use heat-treated substrates. [Explanation of symbols]

[0151] 10...plate member, 11...processing surface, 12...mounting surface, 13...support member, 14...through hole, 15...vertical hole, 19...guide member, 20...heat generating element, 21...heat generating drive circuit, 40...lifting device, 41...lifting pin, 42...connecting member, 90...control device, 91...temperature control unit, 92...lifting control unit, 93...temperature acquisition unit, 94...temperature information setting unit, 95...temperature information storage unit, 96...contact determination unit, 98...operation unit, 99...presentation device, 100...heat processing device, 909...CD-ROM, CA...center, GA...gap, PR...substrate processing area, R1...first area, R2...second area, R3...third area, TS1, TS2...temperature sensor, VC1...first virtual circle, VC2...second virtual circle, VC3...third virtual circle, VL...virtual straight line, W...substrate

Claims

1. A heat treatment apparatus for performing heat treatment on a substrate, a plate member having an upwardly facing processing surface; a plurality of support members provided on the processing surface so as to be able to support the lower surface of the substrate; a heat processing unit that performs heat processing on the substrate supported by the plurality of support members on the processing surface by adjusting the temperature of the processing surface to a predetermined processing temperature; a temperature detection unit that detects the temperature of a portion of the processing surface where the plurality of support members are not provided; a mounting device that mounts the substrate on the plurality of support members; a temperature information storage unit that stores, as reference temperature information, information about temperature changes of the processing surface from the time when sample substrates of the same type as the substrate are placed on the plurality of support members by the mounting device, until a certain period of time has elapsed without the sample substrate coming into contact with the processing surface, while the temperature of the processing surface is adjusted to the processing temperature; a contact determination unit that, when the substrate is placed on the plurality of support members by the placement device with the temperature of the processing surface adjusted to the processing temperature, acquires a temperature change on the processing surface from the time the substrate is placed until the certain time has elapsed based on the detection result of the temperature detection unit, and determines whether a portion of the substrate that is distorted downward is in contact with the processing surface based on the acquired temperature change on the processing surface and the reference temperature information.

2. the substrate is a circular substrate, the processing surface has a circular shape corresponding to the substrate in a plan view, a circular substrate processing area is defined on the processing surface, in which the substrate is to be placed during thermal processing of the substrate; The substrate processing region includes: a first circular region overlapping a portion including a center of the substrate when the substrate is placed in the substrate processing region; a second region having an annular shape adjacent to the first region and surrounding the first region in a plan view; a third region having an annular shape that is adjacent to the second region in a plan view, surrounds the second region, and includes an outer peripheral edge of the substrate processing region; The heat treatment apparatus according to claim 1 , wherein the plurality of support members are distributed on the treatment surface such that at least one support member is located in each of the first region, the second region, and the third region.

3. defining a first virtual circle in the first region of the substrate processing region, the first virtual circle being based on a center of the substrate processing region in a plan view; defining a second virtual circle in the second region of the substrate processing region, the second virtual circle being based on a center of the substrate processing region in a plan view; In the third region of the substrate processing region, when a third virtual circle is defined with a center of the substrate processing region as a reference in a plan view, The plurality of support members include: a plurality of first support members arranged on the first imaginary circle at predetermined angular intervals with respect to the center of the substrate processing region; a plurality of second support members arranged on the second imaginary circle at predetermined angular intervals with respect to the center of the substrate processing region; 3. The heat treatment apparatus according to claim 2, further comprising: a plurality of third support members arranged on said third imaginary circle at predetermined angular intervals with respect to the center of said substrate treatment region.

4. 4. The heat treatment apparatus of claim 3, wherein the number of the plurality of first support members arranged per unit length of the first imaginary circle and the number of the plurality of third support members arranged per unit length of the third imaginary circle are greater than the number of the plurality of second support members arranged per unit length of the second imaginary circle.

5. the temperature detection unit includes a plurality of temperature sensors that detect temperatures of a plurality of portions of the processing surface, 4. The heat treatment apparatus according to claim 2, wherein the plurality of temperature sensors includes a central temperature sensor that overlaps the center of the substrate treatment region in a plan view.

6. the temperature detection unit includes a plurality of temperature sensors that detect temperatures of a plurality of portions of the processing surface, the plurality of temperature sensors include a plurality of intermediate temperature sensors that overlap the second region in a plan view, When a plurality of virtual straight lines are defined that extend radially from the center of the substrate processing region toward the plurality of second support members in a plan view, 4. The thermal processing apparatus according to claim 2, wherein the plurality of intermediate temperature sensors are provided such that at least one intermediate temperature sensor is located between each two imaginary straight lines adjacent to each other around the center of the substrate processing region.

7. the temperature detection unit includes a plurality of temperature sensors that detect temperatures of a plurality of portions of the processing surface, the plurality of temperature sensors include a plurality of peripheral temperature sensors overlapping the third region in a plan view, 5. The heat treatment apparatus according to claim 3, wherein the plurality of peripheral temperature sensors are provided so that at least one peripheral temperature sensor is located between each pair of third support members adjacent to each other on the third imaginary circle.

8. the reference temperature information is a first reference value corresponding to a temperature change amount of the processing surface from the time when the sample substrate is placed on the plurality of support members until a certain time has elapsed, The heat treatment apparatus according to any one of claims 1 to 4, wherein the contact determination unit determines that the substrate is in contact with the processing surface when the actual temperature change detected by the temperature detection unit between the time the substrate is placed and the time the certain period of time has elapsed is greater than the first reference value.

9. the temperature detection unit includes a plurality of temperature sensors that detect temperatures of a plurality of portions of the processing surface, the reference temperature information is a second reference value corresponding to the magnitude of variation in the temperatures detected by the temperature sensors during a period from when the sample substrate is placed on the support members until a certain time has elapsed, The heat treatment apparatus according to any one of claims 1 to 4, wherein the contact determination unit determines that the substrate is in contact with the processing surface when the magnitude of the variation in the temperatures detected by the plurality of temperature sensors between the time the substrate is placed and the time the certain period of time has elapsed is greater than the second reference value.

10. A heat treatment method for performing heat treatment on a substrate using a heat treatment apparatus, comprising: The heat treatment device includes: a plate member having an upwardly facing processing surface; a plurality of support members provided on the processing surface so as to be able to support the lower surface of the substrate; The heat treatment method includes: storing, as reference temperature information, information regarding temperature changes of the processing surface from the time when a sample substrate of the same type as the substrate is placed on the plurality of support members until a certain time has passed without the sample substrate coming into contact with the processing surface, with the temperature of the processing surface adjusted to a predetermined processing temperature; After the storing step, placing the substrate on the plurality of support members in a state where the temperature of the processing surface is adjusted to a predetermined processing temperature; After the placing step, a step of performing a heat treatment on the substrate supported by the plurality of support members on the processing surface by adjusting the temperature of the processing surface to the processing temperature; detecting a temperature of a portion of the processing surface where the plurality of support members are not provided by a temperature detection unit; a step of, when the substrate is placed on the plurality of support members with the temperature of the processing surface adjusted to the processing temperature, acquiring a temperature change of the processing surface from the time the substrate is placed until the certain time has elapsed based on the detection result of the temperature detection unit, and determining whether a portion of the substrate that is warped downward is in contact with the processing surface based on the acquired temperature change of the processing surface and the reference temperature information stored in the storing step.

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