Measurement system and method for adjusting temperature distribution in wafer

Abstract

According to one aspect of the present invention, there is provided a measurement system comprising a wafer and at least one heat flow sensor provided to the wafer, the heat flow sensor being configured to exchange heat with the wafer and thereby measure heat flow from a specific position on the wafer.

Description

Measurement system and method for adjusting wafer temperature distribution

[0001] The present invention relates to a measurement system and a method for adjusting a temperature distribution on a wafer.

[0002] Patent Document 1 discloses a technology relating to a silicon wafer for temperature distribution measurement, which can measure the temperature distribution on the surface of a silicon wafer using an infrared thermo camera, a method for manufacturing the same, and a method for manufacturing a heater plate for heating a semiconductor wafer.

[0003] According to this technology, a silicon wafer for measuring temperature distribution includes a plate-shaped silicon substrate and a blackbody film having an emissivity of 90% or more formed on one surface of the silicon substrate, the blackbody film having an average thickness of 10 μm to 50 μm, and a value obtained by dividing the standard deviation of the thickness of the blackbody film by the average thickness of the blackbody film being less than 0.08.

[0004] Japanese Patent Application Laid-Open No. 2022-153883

[0005] In order to process wafers in semiconductor manufacturing processes and the like to manufacture desired devices, it is preferable to measure information relating to the temperature of the wafers with high accuracy.

[0006] According to one aspect of the present invention, there is provided a metrology system comprising a wafer and at least one heat flow sensor mounted on the wafer, the heat flow sensor configured to measure heat flow from a specific location on the wafer by exchanging heat with the wafer.

[0007] With this configuration, information relating to the wafer temperature can be measured with higher accuracy.

[0008] It is a diagram showing an overview of an example of the configuration of a measurement system 1. It is a plan view of the measurement system 1 shown in Figure 1 from the surface perpendicular direction D1. It is a diagram showing an example of the configuration of a sensor unit 4 shown in Figure 1. It is an A-A cross-sectional view of the measurement system 1 shown in Figure 2. It is a flowchart showing an example of the flow of a method for adjusting the temperature distribution of a wafer.

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the accompanying drawings. Various features shown in the following embodiments can be combined with each other.

[0010] Incidentally, a program for realizing the software appearing in one embodiment may be provided as a non-transitory computer-readable recording medium, or may be provided so as to be downloadable from an external server, or may be provided so that the program is started on an external computer and its functions are realized on a client terminal (so-called cloud computing).

[0011] Furthermore, various information processing according to an embodiment may realize input and output corresponding to the input. Here, the form of information referenced in such information processing (hereinafter referred to as reference information) is not limited as long as an output is obtained as a result of the input. The reference information may be, for example, rule-based information such as a database, a lookup table, or a predetermined function (including a decision formula such as a regression formula constructed using a statistical method), a trained model that has previously trained the correlation between input and output, or a large-scale language model that can output a desired result by inputting a prompt.

[0012] In one embodiment, the term "unit" may include, for example, a combination of hardware resources implemented by a circuit in the broad sense and software information processing that can be specifically realized by these hardware resources. In one embodiment, various information is handled, and this information is represented, for example, by physical values ​​of signal values ​​representing voltage or current, high or low signal values ​​as a binary bit set consisting of 0 or 1, or quantum superposition (so-called quantum bits), and communication and calculations can be performed on the circuit in the broad sense.

[0013] Furthermore, a circuit in a broad sense is a circuit realized by at least an appropriate combination of a circuit, circuitry, a processor, a memory, etc. The processor may be a general-purpose processor or a dedicated circuit. That is, it includes application specific integrated circuits (ASICs), programmable logic devices (e.g., simple programmable logic devices (SPLDs), complex programmable logic devices (CPLDs), and field programmable gate arrays (FPGAs)), etc.

[0014] From the viewpoint of responsiveness, the heat flow sensor described below is preferably a thin-film type heat flow sensor based on the anomalous Nernst effect. The element (thermoelectric conversion element) of the heat flow sensor (i.e., thermoelectric conversion device) may be composed of a compound exhibiting the anomalous Nernst effect. The element may be composed of, for example, a topological ferromagnet or a topological antiferromagnet called a Weyl semimetal, or may be composed of a ferrimagnet, or a combination thereof. The topological ferromagnet is Co ２ Co such as MnGa ２ The metal may have a TX composition (where X is any one of Si, Ge, Sn, Al, and Ga), or the composition formula may be Fe ３ The topological antiferromagnet may be an alloy of a known topological ferromagnet, such as a metal represented by X (X is a stoichiometric or off-stoichiometric composition of a typical or transition element such as Al or Ga). ３The topological antiferromagnet may be a known topological antiferromagnet, such as X (where X is one or more elements selected from Sn, Ge, Ga, Pt, Ir, and Rh, or a compound thereof). The composition ratio of the alloy constituting the topological ferromagnet or topological antiferromagnet is not necessarily stoichiometric as described above, and is not particularly limited as long as it has a partially stoichiometric structure. The compound constituting the element may be, for example, an alloy containing a transition metal, and the alloy may be a compound having a crystal structure with kagome lattice planes of the transition metal and exhibiting the anomalous Nernst effect. The ferrimagnetic material is also not particularly limited as long as it exhibits the anomalous Nernst effect. The structure of the element is not particularly limited, and known materials can be used. The element according to this embodiment may be formed by sputtering, vapor deposition, MBE, plating, sintering, printing, bonding, or the like. The heat flow sensor according to this embodiment may be configured not only to measure heat, but also to detect light, chemical substances, etc.

[0015] 1. An Example of the Measurement System 1 This chapter describes an example of the measurement system 1. FIG. 1 is a diagram showing an outline of an example configuration of the measurement system 1. As shown in FIG. 1, the measurement system 1 includes a chuck 2, a wafer 3, and at least one sensor unit 4. For ease of explanation, the directions that define this measurement system 1 are referred to as a perpendicular direction D1, a first in-plane direction D2, and a second in-plane direction D3. The perpendicular direction D1, the first in-plane direction D2, and the second in-plane direction D3 are orthogonal to one another. The significance of these directions D1 to D3 will be described later.

[0016] The chuck 2 is configured to be able to mount a wafer 3 (described later). The chuck 2 may be configured to be able to adjust the temperature of the wafer 3 (e.g., the temperature distribution of the wafer 3) by exchanging heat with the wafer 3 mounted thereon. For example, the chuck 2 is a ceramic chuck. In one embodiment, the chuck 2 includes a flat plate portion 21, a holder portion 22, and a heater 23.

[0017] The flat plate portion 21 is defined to have a surface perpendicular to the perpendicular direction D1.

[0018] The holding portion 22 is defined to protrude from the flat portion 21 in the direction perpendicular to the surface D1. While the holding portion 22 is defined to have a cylindrical shape, any irregular shape may be adopted. Furthermore, the shape of the holding portion 22 may be any shape as long as it is configured to position the wafer 3 so that the relative positional relationship between the chuck 2 and the wafer 3 is within the tolerance range. For example, the holding portion 22 may be formed in a substantially planar shape with slight irregularities using a predetermined irregularity pattern such as a dimple shape. The arrangement of the holding portions 22 may be periodic or aperiodic. The dimensions of the holding portion 22 shown in the figure (e.g., the protrusion length in the direction perpendicular to the surface D1 and the width within the surface) are for convenience of explanation and may not necessarily represent actual dimensions. For example, the irregular shape of the holding portion 22 is not limited to that visible to the human eye.

[0019] The heater 23 is an example of a temperature adjustment unit and is configured to be able to heat an object. Heat generated from the heater 23 can be transferred to an object in contact with the holding unit 22 via the holding unit 22. In an embodiment, the heater 23 can be disposed at a position corresponding to each of the holding units 22 (for example, a position overlapping at least a portion of the holding unit 22 when viewed in plan from the direction perpendicular to the surface D1). This allows heat from the heater 23 to be efficiently transferred to the holding unit 22.

[0020] The wafer 3 is a plate material formed using a raw material for semiconductor devices, such as a silicon wafer. The wafer 3 can be configured to have a composition similar to that of the base material that serves as the raw material for manufacturing semiconductor devices (in other words, the precursor of the semiconductor devices). In one embodiment, the wafer 3 has a disk shape that has a thickness in the perpendicular direction D1 and extends in the in-plane directions D2 and D3. The wafer 3 has a first surface 31 and a second surface 32.

[0021] The first surface 31 faces the chuck 2 in the perpendicular direction D1. The first surface 31 includes a contact portion 311. The contact portion 311 is configured to contact the holder 22. In one embodiment, the contact portion 311 may be formed as a recess configured to accommodate the holder 22. In this case, for example, if the wafer 3 attempts to shift in the in-plane directions D2 and D3, the contact portion 311 and the holder 22 interfere with each other, thereby preventing the shift. In one embodiment, the contact portion 311 may be in mechanical contact with a temperature adjustment unit (e.g., the heater 23) that adjusts the temperature of the wafer 3. This configuration allows for more efficient transfer of heat from the heater 23 via the contact portion 311. Here, mechanical contact may include heat exchange between the contact portion 311 and the heater 23 via a solid member. The shape of the contact portion 311 is arbitrary, as long as it can be connected to the chuck 2 (particularly the holder 22) by contacting the chuck 2. The second surface 32 is located opposite to the first surface 31 in the thickness direction (for example, the perpendicular direction D1) of the wafer 3. The shape of the second surface 32 is arbitrary, but may be, for example, a flat surface.

[0022] The sensor unit 4 is provided on the wafer 3. In this embodiment, the sensor unit 4 is disposed on the second surface 32 of the wafer 3. The sensor unit 4 is configured to measure the heat flow in and out of the wafer 3 by exchanging heat with the wafer 3. In this embodiment, a plurality of (e.g., six) sensor units 4 are disposed on the second surface 32. The sensor units 4 are configured to form a two-dimensional array on the second surface 32. In this embodiment, three sensor units 4a, 4b, and 4c are disposed along the first in-plane direction D2, and the array of the three sensor units 4a, 4b, and 4c is repeated along the second in-plane direction D3. As a result, the sensor units 4 form a square lattice along the first in-plane direction D2 and the second in-plane direction D3. Specifically, the sensor unit 4c is disposed between the sensor unit 4a and the sensor unit 4b.

[0023] FIG. 2 is a plan view of the measurement system 1 shown in FIG. 1 from the surface-perpendicular direction D1. The plan view from the surface-perpendicular direction D1 corresponds to a plan view of the wafer 3. As shown in FIG. 2, the sensor unit 4 is arranged so that, when the second surface 32 is viewed in plan, at least a portion of the sensor unit 4 (particularly the region of the heat flow sensor 41 described below) overlaps with the contact portion 311. This configuration allows the heat flow transferred from the contact portion 311 to be more efficiently transferred to the heat flow sensor 41. In one embodiment, the heat flow sensor 41 is arranged so that the outer edge of the heat flow sensor 41 in the plan view of the second surface 32 includes the outer edge of the contact portion 311. In this embodiment, when the second surface 32 is viewed in plan from the surface-perpendicular direction D1, the sensor units 4a and 4b are each arranged to overlap one of the contact portions 311, and the sensor unit 4c is arranged so as not to overlap the contact portion 311.

[0024] The wafer 3 may further include a signal processing section 5 and an electrically conductive wiring section 6 .

[0025] The signal processing unit 5 is configured to perform predetermined signal processing on an electrical signal indicating the measurement result (e.g., a voltage signal based on the thermoelectromotive force output from the heat flow sensor 41). For example, the signal processing unit 5 is stacked integrally on the wafer 3 together with the heat flow sensor 41 (and further the sensor unit 4). The signal processing unit 5 may be implemented separately from the wafer 3 or may be provided outside the measurement system 1. The signal processing unit 5 may be an analog circuit capable of performing the signal processing or a computer device capable of performing numerical conversion using hardware such as a processor. The signal processing unit 5 is also configured to control the output mode of each heater 23 based on the measurement result of the sensor unit 4. In this way, the signal processing unit 5 controls the temperature distribution within the surface of the wafer 3 to a desired state.

[0026] The wiring section 6 is configured to connect each of the sensor units 4 arranged on the second surface 32 to the signal processing section 5. An electrical signal indicating the measurement result of the sensor unit 4 described above is transmitted to the signal processing section 5 via the wiring section 6. The wiring section 6 may be, for example, a metal pattern incorporated on the surface of or inside the wafer 3, or a conductor connecting the sensor unit 4 to the signal processing section 5. Note that if each sensor unit 4 and the signal processing section 5 are configured to be capable of wireless communication, the sensor unit 4 may output the measurement result to the signal processing section 5 using any wireless communication method. In this case, the wiring section 6 may be omitted.

[0027] Next, an example of the configuration of the sensor unit 4 will be described. Fig. 3 is a diagram showing an example of the configuration of the sensor unit 4 shown in Fig. 1. As shown in Fig. 3, the sensor unit 4 includes a heat flow sensor 41. The heat flow sensor 41 is configured to measure a heat flow from a specific position on the wafer 3 by exchanging heat with the wafer 3. The heat flow sensor 41 includes a substrate 411, at least one thermoelectric conversion unit 412 (in this embodiment, multiple thermoelectric conversion units 412), wiring 413, and an output unit 414.

[0028] The substrate 411 is configured to have electrical insulation properties and has a main surface defined by a normal line extending along the perpendicular direction D1. The substrate 411 is configured to be in contact with the second surface 32. The substrate 411 may be an insulating film formed on the second surface 32 of the wafer 3.

[0029] The thermoelectric conversion unit 412 is configured to convert a temperature gradient generated by heat exchange with the wafer 3 into an electrical signal based on the thermoelectric effect. The thermoelectric conversion unit 412 may include an anomalous Nernst element configured to output a thermoelectromotive force based on the anomalous Nernst effect through heat exchange with the wafer 3. This configuration allows the heat flow sensor 41 to be formed thin in the perpendicular direction D1, thereby enabling the measurement system 1 to be miniaturized. The anomalous Nernst element generates an electromotive force along a second in-plane direction D3 based on the heat flow flowing in the perpendicular direction D1 (in other words, the temperature gradient in the perpendicular direction D1). For example, each of the thermoelectric conversion units 412 is configured to have spontaneous magnetization in a direction different from the temperature gradient, thereby generating an electromotive force in the in-plane direction due to the temperature gradient. The thermoelectric conversion unit 412 is formed in a thin film shape. The thermoelectric conversion unit 412 may also include magnetic domains configured to be magnetized along the in-plane direction of the thin film. The thermoelectric conversion unit 412 may also be formed in a bulk shape. The thermoelectric conversion portion 412 may be configured to generate a thermoelectromotive force along the direction D1 perpendicular to the surface based on a heat flow in the direction D1 perpendicular to the surface, like a Seebeck element.

[0030] In some embodiments, the heat flow sensor 41 of at least one of the sensor units 4a to 4c (all of them in this embodiment) may be configured to measure components of the heat flow from the wafer 3 in two or more different directions (e.g., in addition to the perpendicular direction D1, a first in-plane direction D2 or a second in-plane direction D3). This configuration allows for multi-plane measurement of the heat inflow or outflow at each position on the wafer 3, thereby improving the accuracy of the temperature distribution measurement using the measurement results. In this case, the thermoelectric conversion unit 412 of the heat flow sensor 41 may be configured to include, for example, a Seebeck element and an anomalous Nernst element. In this case, the Seebeck element induces a thermoelectromotive force in the perpendicular direction D1 in response to the heat flow in the perpendicular direction D1, and the anomalous Nernst element induces a thermoelectromotive force in the second in-plane direction D3 in response to the heat flow in the perpendicular direction D1. The heat flow sensor 41 may be configured to output a single composite electromotive force, obtained by combining the thermoelectromotive forces of these elements by connecting them in series, as an electrical signal. Furthermore, the heat flow sensor 41 may be configured to output the thermoelectromotive force based on the anomalous Nernst element and the thermoelectromotive force based on the Seebeck element separately. This allows for more accurate understanding of the heat distribution within the wafer and more accurate control of the uniform temperature of the wafer 3 during the process. In particular, the heat flow sensor 41 utilizing the anomalous Nernst effect using the above-described topological material or the like can detect both the heat flow perpendicular to the anomalous Nernst element (the surface-perpendicular direction D1) and the heat flow parallel to the element due to the Seebeck effect. For example, the thickness of the Seebeck element is preferably less than 250 micrometers, more preferably less than 100 micrometers, even more preferably less than 10 micrometers, and even more preferably less than 1 micrometer.

[0031] The wiring 413 is configured to connect the plurality of thermoelectric conversion units 412 in series so that the polarities of the units are the same.

[0032] The output unit 414 is a terminal configured to output the sum of the electromotive forces output from all of the thermoelectric conversion units 412. The output unit 414 does not need to be implemented as an actual connection terminal, but may be a virtual terminal connected to an external element. In this embodiment, the heat flow sensor 41 includes a pair of output units 414, which output a total electromotive force V1, which is the sum of the electromotive forces of the thermoelectric conversion units 412. In this embodiment, the heat flow sensor 41 outputs the total electromotive force V1 output from the output unit 414 due to the heat flow associated with the temperature gradient as an electrical signal indicating the measurement result. The output unit 414 is connected to the signal processing unit 5 via the wiring unit 6. In this manner, the heat flow sensor 41 is electrically connected to the wiring unit 6 and configured to output an electrical signal indicating the measurement result regarding the heat flow via the wiring unit 6. With this configuration, the measurement system 1 can be integrated with the wafer 3, providing an easy-to-use measurement system 1.

[0033] The sensor unit 4 may further include a temperature sensor 42. The temperature sensor 42 is configured to measure the temperature of the wafer 3 (particularly, the temperature at a specific position on the wafer 3 corresponding to each sensor unit 4). The temperature sensor 42 is mounted on the substrate 411, for example, together with the thermoelectric conversion unit 412. The temperature sensor 42 may be any configuration, such as a resistance thermometer, a thermocouple, or an electric thermometer. The temperature sensor 42 is connected to the signal processing unit 5 via the wiring unit 6. An electrical signal indicating the measurement result by the temperature sensor 42 is transmitted to the signal processing unit 5 via the wiring unit 6. The signal processing unit 5 performs signal processing to estimate the temperature distribution of the wafer 3 based on the detection result of the heat flow sensor 41 of each sensor unit 4, as well as the measurement result of the wafer 3 temperature by the temperature sensor 42 of each sensor unit 4. The heat flow sensor 41 and the temperature sensor 42 may be formed as a single element in the sensor unit 4. This integrated configuration allows for more efficient thermal coupling between the temperature sensor 42 and the heat flow sensor 41. Therefore, the temperature sensor 42 and the heat flow sensor 41 can be placed in a more similar environment to measure a variety of information related to the temperature distribution of the wafer 3. The heat flow sensor 41 and the temperature sensor 42 may be provided, for example, so as to be embedded in the surface of the wafer 3. The manner in which the heat flow sensor 41 and the temperature sensor 42 are provided on the wafer 3 is not particularly limited.

[0034] Next, an example of the heat flow through each sensor unit 4a, 4b, and 4c will be described. FIG. 4 is a cross-sectional view taken along the line A-A of the measurement system 1 shown in FIG. 2. As an example, the heat flow from the heater 23 located in the direction perpendicular to the wafer surface D1 from the sensor unit 4a to the wafer 3 is denoted as J11, and the heat flow from the heater 23 located in the direction perpendicular to the wafer surface D1 from the sensor unit 4b to the wafer 3 is denoted as J12. In the example shown in FIG. 4, J11 > J12. In this case, at least a portion of the heat flow J11 is transferred to the sensor unit 4a via the wafer 3. The heat flow that flows into the sensor unit 4a flows out to the outside as a heat flow J21 that includes a component in the direction perpendicular to the wafer surface D1. Based on the heat flow J21, the sensor unit 4a outputs a thermoelectromotive force based on heat exchange with a specific position on the second surface 32 of the wafer 3 where the sensor unit 4a is located.

[0035] Similarly, at least a portion of the heat flow J12 is transmitted to the sensor unit 4b via the wafer 3. The heat flow that flows into the sensor unit 4b flows out as a heat flow J22 that includes a component in the perpendicular direction D1. Based on the heat flow J22, the sensor unit 4b outputs a thermoelectromotive force based on heat exchange with the specific position, which is the region of the second surface 32 of the wafer 3 where the sensor unit 4b is provided. In this way, the sensor units 4a and 4b can measure the heat flow distribution in the region of the wafer 3 where they are provided.

[0036] Furthermore, some of the heat flows J11 and J12 flowing into the wafer 3 may flow within the wafer 3 as heat flows in the in-plane directions D2 and D3. In this embodiment, since J11 > J12, a heat flow J23 may flow from sensor unit 4a to sensor unit 4b in the first in-plane direction D2. In this case, sensor unit 4c can measure the heat flow J23. In this manner, by using sensor units 4a, 4b, and 4c to measure the heat flow distribution in the wafer 3's plane-normal direction D1 and the heat flow distribution in a plane perpendicular to the plane-normal direction D1 (e.g., within a plane defined by the two in-plane directions D2 and D3), it is possible to detect with high responsiveness a sign of a change in the temperature distribution of the wafer 3 that is difficult to grasp based on temperature alone. In other words, at least one heat flow sensor 41 includes the heat flow sensor 41 of sensor unit 4a or 4b as a first heat flow sensor. These heat flow sensors 41 are configured to measure at least the components J21 and J22 of the heat flows J11 and J12 from the wafer 3 that flow in a direction perpendicular to the plane (e.g., the first surface 31) of the wafer 3 (e.g., the surface-perpendicular direction D1). This configuration allows for the heat dissipation from the wafer 3 to the outside in the surface-perpendicular direction D1 to be monitored with high responsiveness, thereby enabling the detection of signs of changes in the temperature distribution of the wafer 3, which are difficult to monitor using temperature alone. In some embodiments, at least one heat flow sensor 41 may include a heat flow sensor 43 as a second heat flow sensor. The heat flow sensor 43 is configured to measure the component of the heat flow from the wafer 3 that flows along the in-plane direction of the wafer 3 (here, the first in-plane direction D2). This configuration allows for the measurement of heat transfer within the wafer 3, thereby enabling the multifaceted acquisition of factors affecting the temperature distribution of the wafer 3. From another perspective, providing the heat flow sensor 41 on the wafer 3 allows for the direct sensing of the heat flow in the wafer 3. This allows the heat flow to be measured earlier than the temperature of the wafer 3, enabling precise temperature control of the wafer 3. Specifically, for example, by using the heat flow sensor 41 to measure the flow of heat into and out of the substrate in the semiconductor manufacturing process, it is possible to determine at an earlier timing which parts heat is entering and which parts heat is emitting directly, rather than measuring the change in the temperature of the substrate.In the measurement system 1 according to this embodiment, the heat flowing in and out during the process is directly captured, thereby enabling higher accuracy in adjusting the process control and heater control for uniformly heating the wafer 3.

[0037] As shown in FIG. 4 , the measurement system 1 may further include a circuit unit 7. The circuit unit 7 may include any element capable of performing operations on the sensor unit 4, such as supplying power to the sensor unit 4 (particularly the heat flow sensor 41), converting an electrical signal output from the sensor unit 4, or applying an external field such as a magnetic field to the sensor unit 4. For example, the circuit unit 7 may be built into the wafer 3 or provided on the surface (second surface 32, etc.) of the wafer 3. Furthermore, as long as the circuit unit 7 is electrically connected to the sensor unit 4, the circuit unit 7 may be provided integrally with the sensor unit 4 or indirectly via the wafer 3. The circuit unit 7 may be configured to function as, for example, an IC chip or a sensor chip. For example, to improve accuracy, the sensor unit 4 (particularly the heat flow sensor 41 and the temperature sensor 42) may be bonded to the wafer 3 using a die bond or a thermal bonding method (e.g., paste) that allows the circuit IC chip or sensor chip to be bonded to the wafer 3. Furthermore, methods such as wire bonding, flip chip, solder, bump bonding, and TSV (through silicon via) may be used to electrically connect the sensor unit 4 and the circuit section 7. This allows electrical connection with the wafer 3, and electrical signals and power can be connected to the outside or to the signal processing section 5 through wiring within the wafer 3. The circuit section 7 may be configured to perform at least some of the functions of the signal processing section 5.

[0038] 2. Example of a Method for Adjusting the Temperature Distribution of a Wafer This section describes an example of a method for adjusting the temperature distribution of an arbitrary wafer 3 using the above-described measurement system 1. Figure 5 is a flowchart showing an example of the flow of the method for adjusting the temperature distribution of a wafer.

[0039] 5, first, in step S1, the wafer 3 is placed on the chuck 2. This allows the heater 23, which serves as a temperature adjustment unit for adjusting the temperature of the wafer 3, to come into contact with the wafer 3. This allows the sensor unit 4 (particularly the heat flow sensor 41) provided on the wafer 3 to measure the heat flow from a specific position on the wafer 3 by exchanging heat with the wafer 3.

[0040] Next, in step S2, the signal processing unit 5 acquires from the sensor unit 4 (for example, via the wiring unit 6) electrical signals indicating the measurement results of the heat flow at a specific position output from each of the plurality of heat flow sensors 41. At this time, the electrical signals may be configured to be transmitted to the signal processing unit 5 via the circuit unit 7. In this case, the circuit unit 7 may perform processing such as amplification and noise removal on the electrical signals from the sensor unit 4.

[0041] Next, in step S3, the signal processing unit 5 estimates the temperature distribution of the wafer 3 based on the acquired electrical signal (measurement result of the sensor unit 4) from the sensor unit 4. For example, the signal processing unit 5 measures the heat flow distribution of the wafer 3 based on the measurement result of the heat flow sensor 41, and estimates the temperature distribution of the wafer 3 or its change over time based on the measurement result of the heat flow distribution. If the sensor unit 4 includes a temperature sensor 42, the signal processing unit 5 may construct a tentative temperature distribution of the wafer 3 based on the measurement result of the temperature sensor 42, and correct the tentative temperature distribution based on the heat flow distribution, thereby estimating the temperature distribution of the wafer 3.

[0042] Next, in step S4, the signal processing unit 5 sets an output target value for each heater 23 based on the result of the estimation of the temperature distribution of the wafer 3 estimated in step S3. For example, the signal processing unit 5 sets the target output value for the heater 23 so that the temperature at each position on the wafer 3 approaches a uniform temperature distribution that coincides with a predetermined target temperature for the entire wafer 3. The target output value may be specified as, for example, a power value.

[0043] Next, in step S5, the signal processing unit 5 controls the power flowing to each heater 23 so that the output of each heater 23 reaches the set target output value. For example, in this manner, the signal processing unit 5 adjusts the temperature distribution of the wafer 3 by controlling the output mode of the heater 23 based on the measurement results of the sensor unit 4. With this configuration, when processing a semiconductor precursor placed on the chuck 2, the temperature of the precursor can be adjusted with greater precision, thereby making the semiconductor manufacturing process more efficient.

[0044] In this method, furthermore, in step S6, the control sequence of the heaters 23 executed in step S5 (for example, the transition of the output target value of each heater 23 relative to the target temperature, the transition of the power flowing to the heaters 23, etc.) may be recorded. The control process may be recorded, for example, in the memory of the signal processing unit 5 or in an external storage medium (not shown).

[0045] Next, in step S7, a semiconductor precursor is placed on the chuck 2 instead of the wafer 3, and processing (e.g., heating, processing, film formation, etc.) is performed on the precursor. At this time, a control device (not shown) executes the recorded control sequence for the heater 23 to homogenize the temperature distribution of the semiconductor precursor toward the target temperature. This allows semiconductor devices to be manufactured from the semiconductor precursor. This configuration makes it possible to suppress a decrease in yield when manufacturing semiconductor devices from the semiconductor precursor.

[0046] 3. Others The above-described aspects of the measurement system 1 etc. are merely examples, and the present invention is not limited to these.

[0047] The temperature adjustment unit is not limited to the heater 23 and may be any unit capable of adjusting the temperature or temperature distribution of the wafer 3. For example, the measurement system 1 may include a heat absorption element such as a Peltier element instead of (or in addition to) the heater 23 as the temperature adjustment unit.

[0048] The measurement system 1 does not necessarily include the chuck 2. For example, the chuck 2 may be treated as an external member of the measurement system 1.

[0049] In the above embodiment, the signal processing unit 5 performs various storage and control operations, but multiple external devices may be used instead of the signal processing unit 5. That is, various information and programs may be stored in a distributed manner in multiple external devices using blockchain technology or the like.

[0050] Furthermore, the above embodiment provides the following technical idea: (A) A measuring device comprising: a wafer; a heat flow sensor provided on the wafer; and an output unit (e.g., a wired or wireless communication means or a controller) that outputs a signal obtained from the heat flow sensor.

[0051] (B) A method for detecting a heat flow on the surface of a substrate to be processed in a semiconductor process, and controlling a process (heating process, processing process, film formation process, etc.) on the substrate using a signal based on the detected heat flow.

[0052] Each of the above (A) and (B) can be further combined with the following configurations. The heat flow sensor may be provided on the surface of the wafer. A controller for processing the signal output from the heat flow sensor may be provided on / outside the wafer. A temperature sensor may be further provided. The temperature sensor may be integrated with the heat flow sensor. The heat flow sensor may measure heat flow perpendicular to the element using the anomalous Nernst effect. The heat flow sensor may measure heat flow perpendicular to / parallel to the element using the Seebeck effect. The element constituting the heat flow sensor may be a topological material (topological ferromagnet, Weyl semimetal, topological antiferromagnet), a ferrimagnet, an L10-type alloy, a D022-type alloy, etc. There is no particular limitation as long as it is a material that exhibits the anomalous Nernst effect. The heat flow sensor element and the temperature sensor element may be integrated. The heat flow sensor element (and the temperature sensor element) may be thermally bonded to the wafer. The heat flow sensor element may be formed and processed directly on the wafer, or may be a separate element embedded in the wafer. In addition to the heat flow sensor, a temperature sensor or other circuits may be provided on the wafer. A heater for heating the wafer may be provided. The heater may be of either a contact type or a non-contact type. A chuck for holding the wafer may be provided.

[0053] The measurement system 1 and the like may be provided in the following aspects.

[0054] (1) A measurement system comprising a wafer and at least one heat flow sensor provided on the wafer, the heat flow sensor configured to measure heat flow from a specific position on the wafer by exchanging heat with the wafer.

[0055] (2) In the measurement system described in (1) above, the at least one heat flow sensor includes a first heat flow sensor, and the first heat flow sensor is configured to measure at least a component of the heat flow from the wafer that flows in a direction perpendicular to the plane of the wafer.

[0056] (3) In the measurement system described in (1) or (2) above, the at least one heat flow sensor includes a second heat flow sensor, and the second heat flow sensor is configured to measure a component of the heat flow from the wafer that flows along the in-plane direction of the wafer.

[0057] (4) In the measurement system described in any one of (1) to (3) above, at least one of the heat flow sensors is configured to measure components of the heat flow from the wafer in two or more different directions.

[0058] (5) The measurement system according to any one of (1) to (4) above, further comprising a temperature sensor, the temperature sensor being configured to measure the temperature of the wafer.

[0059] (6) In the measurement system described in any one of (1) to (5) above, the wafer has an electrically conductive wiring portion, and the heat flow sensor is electrically connected to the wiring portion and configured to output an electrical signal indicating the measurement result via the wiring portion.

[0060] (7) In the measurement system described in (6) above, the wafer further includes a signal processing unit connected to the wiring section, and the signal processing unit is configured to perform predetermined signal processing on an electrical signal indicating the measurement result transmitted via the wiring section.

[0061] (8) In the measurement system described in (7) above, the signal processing unit is stacked integrally on the wafer together with the heat flow sensor.

[0062] (9) In the measurement system described in any one of (1) to (8) above, the wafer has a first surface and a second surface, the first surface has a contact portion that mechanically contacts a temperature adjustment unit that adjusts the temperature of the wafer, the second surface is located opposite the first surface in the thickness direction of the wafer, and the heat flow sensor is arranged on the second surface.

[0063] (10) In the measurement system described in (9) above, the heat flow sensor is positioned so that at least a portion of the heat flow sensor overlaps the contact portion when the second surface is viewed in a plane.

[0064] (11) In the measurement system described in any one of (1) to (10) above, the heat flow sensor includes an anomalous Nernst element configured to output a thermoelectric power based on the anomalous Nernst effect by heat exchange with the wafer.

[0065] (12) A method for adjusting a temperature distribution of a wafer, comprising the following steps: in an installation step, a temperature adjustment unit that adjusts the temperature of the wafer is brought into contact with the wafer, the wafer is provided with a plurality of heat flow sensors, and the heat flow sensors are configured to measure heat flow from specific positions on the wafer by heat exchange with the wafer, in an acquisition step, measurement results of the heat flow at the specific positions output from each of the plurality of heat flow sensors are acquired, and in a temperature adjustment step, the temperature distribution of the wafer is adjusted by controlling the output mode of the temperature adjustment unit based on the measurement results. Of course, this is not limited to this.

[0066] Finally, while various embodiments of the present disclosure have been described, they are presented as examples and are not intended to limit the scope of the invention. The novel embodiments may be embodied in various other forms, and various omissions, substitutions, and modifications may be made without departing from the spirit of the invention. Such embodiments and modifications are intended to be included within the scope and spirit of the invention, as well as within the scope of the inventions and their equivalents as defined in the claims.

[0067] 1: Measurement system, 2: Chuck, 3: Wafer, 4: Sensor unit, 4a: Sensor unit, 4b: Sensor unit, 4c: Sensor unit, 5: Signal processing unit, 6: Wiring unit, 7: Circuit unit, 21: Flat plate unit, 22: Holding unit, 23: Heater, 31: First surface, 32: Second surface, 41: Heat flow sensor, 42: Temperature sensor, 43: Heat flow sensor, 311: Contact unit, 411: Substrate, 412: Thermoelectric conversion unit, 413: Wiring, 414: Output unit, D1: Perpendicular to surface direction, D2: First in-plane direction, D3: Second in-plane direction, IC: Circuit unit, J11: Heat flow, J12: Heat flow, J21: Heat flow, J22: Heat flow, J23: Heat flow

Claims

1. A measurement system comprising: a wafer; and at least one heat flow sensor provided on the wafer, the heat flow sensor configured to measure heat flow from a specific position on the wafer by exchanging heat with the wafer.

2. A measurement system according to claim 1, wherein said at least one heat flow sensor includes a first heat flow sensor, said first heat flow sensor being configured to measure at least a component of the heat flow from said wafer that flows in a direction perpendicular to the plane of said wafer.

3. A measurement system as described in claim 1 or 2, wherein the at least one heat flow sensor includes a second heat flow sensor, and the second heat flow sensor is configured to measure a component of the heat flow from the wafer that flows along an in-plane direction of the wafer.

4. A measurement system according to any one of claims 1 to 3, wherein at least one of the heat flow sensors is configured to measure components of the heat flow from the wafer in two or more different directions.

5. The measurement system according to any one of claims 1 to 4, further comprising a temperature sensor, the temperature sensor being configured to measure the temperature of the wafer.

6. A measurement system according to any one of claims 1 to 5, wherein the wafer is provided with an electrically conductive wiring section, and the heat flow sensor is electrically connected to the wiring section and configured to output an electrical signal indicating the measurement result via the wiring section.

7. A measurement system as described in claim 6, wherein the wafer further comprises a signal processing unit connected to the wiring section, and the signal processing unit is configured to perform a predetermined signal processing on an electrical signal indicating the measurement result transmitted via the wiring section.

8. A measurement system according to claim 7, wherein the signal processing unit is integrally stacked on the wafer together with the heat flow sensor.

9. A measurement system according to any one of claims 1 to 8, wherein the wafer has a first surface and a second surface, the first surface has a contact portion that mechanically contacts a temperature adjustment portion that adjusts the temperature of the wafer, the second surface is located opposite the first surface in the thickness direction of the wafer, and the heat flow sensor is disposed on the second surface.

10. A measurement system according to claim 9, wherein the heat flow sensor is positioned such that at least a portion of the heat flow sensor overlaps with the contact portion when the second surface is viewed in a plan view.

11. A measurement system according to any one of claims 1 to 10, wherein the heat flow sensor includes an anomalous Nernst element configured to output a thermoelectromotive force based on the anomalous Nernst effect by heat exchange with the wafer.

12. A method for adjusting the temperature distribution of a wafer, comprising the following steps: in an installation step, a temperature adjustment unit for adjusting the temperature of the wafer is brought into contact with the wafer, the wafer is provided with a plurality of heat flow sensors, and the heat flow sensors are configured to measure heat flow from a specific position on the wafer by heat exchange with the wafer; in an acquisition step, measurement results of the heat flow at the specific position output from each of the plurality of heat flow sensors are acquired; and in a temperature adjustment step, the temperature distribution of the wafer is adjusted by controlling the output mode of the temperature adjustment unit based on the measurement results.

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