Method for evaluating substrate processing apparatus, substrate processing apparatus, and method for manufacturing article

Abstract

To solve the problem in which: there is a demand for an evaluation method for appropriately evaluating the cleanliness in a processing apparatus that processes a substrate.SOLUTION: Provided is a method for evaluating a substrate processing apparatus having a processing unit that processes a substrate, the method including: sucking in air from a plurality of suction ports provided in an area where a substrate stage operates, which has a substrate mounted thereon and moves inside the apparatus; correcting a measurement result obtained through measurement of particles included in the air sucked in from the suction ports according to the positions of the suction ports; and evaluating the state of the apparatus according to the corrected measurement result.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a method for evaluating a substrate processing apparatus, a substrate processing apparatus, and a method for manufacturing an article. [Background technology]

[0002] As the demand for miniaturization of semiconductor devices and MEMS increases, imprinting technology, which can form fine patterns (structures) on the order of a few nanometers on a substrate, is attracting attention in addition to conventional photolithography technology. Imprinting technology is a microfabrication technology in which an uncured imprinting material is supplied (applied) onto a substrate, and the imprinting material is brought into contact with a mold to form a pattern of the imprinting material on the substrate that corresponds to the fine uneven pattern formed on the mold.

[0003] In such imprinting technology, if the imprinting material on the mold and substrate is brought into contact with each other when particles (foreign matter) are attached to the substrate or mold, not only will it be impossible to form a structure of the desired shape, but there is also the possibility that the mold or substrate will be damaged. Therefore, it is necessary to perform the imprinting process in a substrate processing apparatus, such as an imprinting apparatus, with as few particles as possible.

[0004] Particles that are expected to be generated within such equipment include those generated by equipment operations such as sliding and friction, such as the operation of the stage, transport robot, and various actuators. When the imprint material is applied to the substrate by the inkjet method, the imprint material generated when it is discharged may become mist and float, dry and solidify, and turn into particles. In addition, particles that adhere to each component during the assembly of the equipment may spread within the equipment due to a slight change in condition after the equipment is started up.

[0005] In order to check whether particles inside an equipment have reached a certain level of cleanliness, it has been common to perform a dummy operation such as transporting a substrate inside the equipment and then check the equipment condition from the number of particles adhering to the substrate.

[0006] However, in apparatuses that require a high level of cleanliness, such as imprint apparatuses, the number of particles that adhere to the substrate is small even when dummy transport is performed, and long periods of dummy operation are required to reliably evaluate the condition inside the apparatus.

[0007] One method for understanding the state inside the equipment without performing such dummy operations is to install a particle counter that counts the particles contained in the air inside the equipment and evaluate the operation of the equipment from the count value.

[0008] Patent Document 1 discloses an imprint apparatus equipped with a measuring instrument that measures the particle concentration in the space where the imprint process is performed, while Patent Document 2 discloses an imprint apparatus equipped with a measuring instrument that measures particles in the space where the mask and wafer face each other. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] JP 2013-026474 A [Patent Document 2] JP 2019-212673 A Summary of the Invention [Problem to be solved by the invention]

[0010] However, the methods of Patent Documents 1 and 2 merely assess the air by sucking it from a predetermined location inside the equipment, and are not able to properly assess whether the cleanliness inside the equipment is maintained to a level that will not cause problems when substrates are transported inside the equipment.

[0011] The present invention has been made in consideration of the above problems, and has an object to provide an evaluation method capable of appropriately evaluating the cleanliness inside an apparatus. [Means for solving the problem]

[0012] In consideration of the above problems, the present invention provides a method for evaluating a substrate processing apparatus having a processing section for processing substrates, comprising the steps of: sucking in air from a plurality of intake ports provided in an area where a substrate stage that carries the substrate and moves within the apparatus operates; measuring particles contained in the air sucked in from the plurality of suction ports; correcting the measured measurement results from each suction port in accordance with the position of the suction port; and evaluating the state of the apparatus in accordance with the corrected measurement results from each suction port. Effect of the Invention

[0013] According to the present invention, it is possible to provide an advantageous configuration for appropriately evaluating the cleanliness inside an apparatus. [Brief description of the drawings]

[0014] [Figure 1] 1A is a schematic diagram showing the configuration of an imprint apparatus, and FIG. 1B is a schematic diagram showing a cross section of the imprint apparatus shown in FIG. [Diagram 2] 1A is a diagram showing data from a particle counter when a dummy operation is being performed, and FIG. 1B is data on particles adhering to a substrate when a dummy operation is being performed. [Diagram 3] 1A is a diagram showing data from a particle counter when a dummy operation is being performed, and FIG. 1B is data on particles adhering to a substrate when a dummy operation is being performed. [Figure 4] (a) A diagram showing data from a particle counter when a dummy operation is being performed, and (b) Counter data from the particle counter when a dummy operation is being performed, classified by particle size. [Diagram 5](a) The counter data in FIG. 4(a) is converted into adhesion flux data. (b) The data in FIG. 4(b) is converted into adhesion flux data. [Figure 6] 1A is a graph showing particle counter data converted into adhesion flux data during a dummy operation, and FIG. 1B is a graph showing adhesion data of particles adhered to a substrate during a dummy operation. [Figure 7] 11 is a flowchart illustrating a flow of correlating data indicating the state of particles in an apparatus and determining a weighting coefficient. [Figure 8] 11 is a flowchart illustrating a flow of evaluating the cleanliness inside the apparatus using a weighting coefficient. [Figure 9] 1A to 1C are diagrams for explaining a method for manufacturing an article. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. In each drawing, the same reference numerals are used to refer to the same components, and duplicated explanations will be omitted.

[0016] First Embodiment An example of a substrate processing apparatus to which the evaluation method according to the present invention can be applied will be described below using an imprint apparatus as an example, but the method may also be applied to substrate processing apparatuses other than imprint apparatuses. FIG. 1(a) is a schematic diagram showing the configuration of an imprint apparatus 1. FIG. 1(b) is a diagram showing the cross section A-A' of FIG. 1(a) and the main units arranged in the space above and below the cross section A-A'. The imprint apparatus 1 is a lithography apparatus used in the manufacturing process of semiconductor devices and the like, and performs an imprint process in which a pattern is formed on an imprint material on a substrate using a mold. The imprint apparatus 1 hardens the imprint material while the mold on which the pattern is formed is in contact with the imprint material supplied (applied) to the substrate, and transfers the pattern onto the substrate by separating the mold from the hardened imprint material.

[0017] The imprint material uses a curable composition (sometimes called an uncured resin) that is cured when curing energy is applied. The curing energy may be electromagnetic waves, heat, or the like. The electromagnetic waves may be, for example, infrared light, visible light, ultraviolet light, or the like, whose wavelength is selected from the range of 10 nm to 1 mm.

[0018] The curable composition is a composition that is cured by irradiation with light or by heating. The photocurable composition that is cured by irradiation with light contains at least a polymerizable compound and a photopolymerization initiator, and may contain a non-polymerizable compound or a solvent, as necessary. The non-polymerizable compound is at least one selected from the group consisting of a sensitizer, a hydrogen donor, an internal mold release agent, a surfactant, an antioxidant, a polymer component, and the like.

[0019] The imprint material may be applied in the form of a film on the substrate by a spin coater or a slit coater. The imprint material may also be applied in the form of droplets, or in the form of islands or a film formed by connecting a plurality of droplets, by a liquid jet head. The viscosity of the imprint material (at 25° C.) is, for example, 1 mPa·s or more and 100 mPa·s or less.

[0020] The substrate is made of glass, ceramics, metal, resin, etc., and may have a member made of a material different from the substrate formed on its surface as necessary. Specific examples of the substrate include silicon wafers, compound semiconductor wafers, and glass wafers containing quartz as a material. Hereinafter, the substrate will be referred to as a wafer.

[0021] Mold 100 (also referred to as a mold or contact member) has a rectangular outer periphery, and has a pattern portion provided with a three-dimensional pattern (a concave-convex pattern to be transferred to substrate 101, such as a circuit pattern) on a surface (pattern surface) facing substrate 101. Mold 100 is made of a material capable of transmitting light, such as quartz.

[0022] In this embodiment, an example of an imprinting apparatus that employs a photocuring method in which the imprinting material is cured by irradiation with light will be described. In the following description, the direction parallel to the optical axis of an irradiation optical system, which will be described later, that irradiates light onto the imprinting material on the substrate, is defined as the Z-axis direction, and two directions perpendicular to each other in a plane perpendicular to the Z-axis direction are defined as the X-axis direction and the Y-axis direction.

[0023] Next, each part of the imprinting apparatus 1 will be described with reference to FIG. 1. The mold chuck 110 (member holding part) attracts and holds the mold 100 by vacuum suction force or electrostatic force. The mold driving mechanism 106 holds the mold chuck 110 and moves the mold 100. The mold driving mechanism 106 moves the mold 100 in the Z-axis direction so as to selectively press (imprint) the mold 100 against an imprint material (not shown) on the substrate 101 or pull (release) the mold 100 from the imprint material on the substrate 101. For example, a linear motor or an air cylinder can be used as an actuator applicable to the mold driving mechanism 106. The mold driving mechanism 106 may be composed of a plurality of driving systems, such as a coarse movement driving system and a fine movement driving system, in order to position the mold 100 with high accuracy. Furthermore, the mold driving mechanism 106 may be configured to be capable of moving the mold 100 not only in the Z-axis direction, but also in the X-axis direction or the Y-axis direction. Furthermore, the mold driving mechanism 106 may be configured to have a tilt function for adjusting the position of the mold 100 in the θ (rotation around the Z-axis) direction or the inclination of the mold 100. Furthermore, when the mold 100 is imprinted on or released from the substrate 101, if particles (foreign matter) are present between the substrate 101 and the mold driving mechanism 106, the particles may adhere to the charged mold 100. In this case, the mold driving mechanism 106 may be configured with a charged plate that attracts particles by utilizing electrostatic force.

[0024] The light irradiation unit 104 has a light source and an irradiation optical system, and the irradiation optical system is equipped with a combination of optical elements described below. In the imprint process, the light irradiation unit 104 irradiates light (e.g., ultraviolet light) onto the imprint material on the substrate 101 via a mirror 105 and the mold 100. The light irradiation unit 104 has a light source and optical elements (lenses, mirrors, light shields, etc.) for adjusting the light from the light source to a light state (light intensity distribution, illumination area, etc.) appropriate for the imprint process.

[0025] When a thermal curing method is adopted instead of a photocuring method, the imprint apparatus 1 can adopt a heat source for curing the imprint material (thermosetting imprint material) as a curing unit instead of the light irradiation unit 104.

[0026] The alignment scopes 107a and 107b can measure the positional deviation in the X-axis and Y-axis directions between the alignment marks formed on the substrate 101 and the alignment marks formed on the mold 100, and are used to align the substrate 101 and the mold 100.

[0027] The spread camera 103 is a camera for monitoring the process of imprinting and releasing the mold 100 and the substrate 101 in real time.

[0028] The liquid ejection device 112 is used as a processing unit that supplies the imprint material onto the substrate 101 by an inkjet method based on preset supply amount information. The supply amount of the imprint material supplied from the liquid ejection device 112 (i.e., the supply amount information) can be set according to the thickness of the imprint material pattern formed on the substrate 101 (residual film thickness), the density of the imprint material pattern, etc.

[0029] The gas supply mechanism 108 has a function of supplying gas to prevent particles generated inside the imprint apparatus 1 from entering the periphery of the mold 100 and the substrate 101.

[0030] A plurality of intake ports 200 to 204 are provided around the area where the substrate stage of the imprint apparatus 1 operates, i.e., in a space above the operating area (referred to as a wafer stage space), and each of them sucks in air inside the imprint apparatus 1. These multiple intake ports 200 to 204 are arranged at different positions within the apparatus, making it possible to evaluate the state of particles at various locations within the apparatus. A measurement unit 131 (measurement means) such as a particle counter can individually count the number of particles contained in the air obtained from each of the multiple intake ports 200 to 204.

[0031] The substrate chuck 118 (substrate holding unit) attracts and holds the substrate 101 by vacuum suction force or electrostatic force. The air purge plate 120 is disposed around the substrate 101 and regulates the air flow near the substrate. The substrate stage 119 is equipped with the substrate chuck 118 and the air purge plate 120 and is movable within the XY plane. That is, the substrate 101 moves within the apparatus as the substrate stage 119 moves. When the mold 100 is pressed against the imprint material on the substrate 101, the position of the mold 100 and the position of the substrate 101 can be aligned with each other by adjusting the position of the substrate stage 119 using the measurement results of the alignment scopes 107a and 107b.

[0032] The substrate stage 119 may be configured to be able to move the substrate 101 not only in the X-axis direction and the Y-axis direction, but also in the Z-axis direction. Note that imprinting and release of the mold 100 in the imprint apparatus 1 is achieved by moving the mold 100 in the Z-axis direction. However, it may also be achieved by moving the substrate 101 in the Z-axis direction. Also, imprinting and release of the mold 100 may also be achieved by moving both the mold 100 and the substrate 101 relatively in the Z-axis direction.

[0033] The substrate chuck maintenance mechanism 111 has a function of cleaning the surface of the substrate chuck 118 and a function of replacing the substrate chuck 118 .

[0034] The mold transport robot 109 is a robot that transports a mold, and has the function of taking out a mold from a stocker (not shown) that temporarily stores molds arranged in the apparatus, and transporting it to a mold chuck 110.

[0035] The base plate 114 supports the mold driving mechanism 106, the liquid ejection device 112, the mold transport robot 109, the substrate chuck maintenance mechanism 111, etc. The stage base 113 supports the substrate stage 119.

[0036] The control unit 50 includes a CPU, memory, etc., and can control each part of the imprint apparatus 1 to perform imprint processing, control the loading and unloading of the substrate / mold, and further control particle evaluation of the imprint apparatus, which will be described later.

[0037] One of the major factors that determines the usable period of the mold 100 used in the imprint process, that is, the mold lifespan, is particles (foreign matter) that adhere to the substrate 101 or the mold 100. If the imprint process (pattern formation) is performed in a state where particles are adhered to the substrate 101 or the mold 100, not only will defects occur in the semiconductor device, but the fine pattern structure of the mold 100 will be damaged, making the mold 100 itself unusable.

[0038] The expected particles include particles generated by device operations such as sliding and friction, such as the operations of the stage, the transport robot, and various actuators described above. When the imprint material is applied to the substrate 101 by an inkjet method, the imprint material generated when the imprint material is discharged may become mist, drift, dry, solidify, and turn into particles. In addition, particles that are weakly attached to the surfaces of each member and unit during the assembly of the device may detach from the surface and turn into particles after the device is started up due to a slight change in condition. In addition, particles may be mixed in when the air conditioning equipment is stopped for device maintenance after the device is stopped.

[0039] Therefore, when performing imprint processing or the like, it is necessary to confirm that the equipment is clean enough to withstand operation before performing the process, and it is required to determine the state of particles in the equipment and evaluate the performance of the equipment. As a method for such performance evaluation, a method can be used in which a bare wafer before processing is transported inside the equipment, and the number of particles attached to the bare wafer by the transport operation is measured using a particle inspection device or the like, thereby quantifying and evaluating the particles inside the equipment. The transport of the bare wafer inside the equipment performed at this time can be performed as an operation (dummy operation) inside the equipment that simulates a normal imprint operation as much as possible, thereby enabling a more reliable evaluation.

[0040] However, imprinting equipment requires a higher level of cleanliness than semiconductor exposure equipment. Therefore, in the case of equipment that already maintains a certain level of cleanliness at the evaluation stage, the number of particles present in the equipment is extremely small to begin with, and there is a possibility that the condition of the equipment cannot be evaluated by transporting bare wafers in the equipment for a short time. Although it is possible to transport bare wafers for a long time to perform an accurate evaluation, this would take a huge amount of time to evaluate the processing equipment, which would result in long downtimes for the equipment and is not practical.

[0041] As a method for grasping the state inside the apparatus without performing such a dummy operation, a method has been considered in which a particle counter is installed inside the apparatus and the operation of the apparatus is evaluated from the count value.

[0042] However, the position where the particle counter can measure particles is predetermined by the position of the air intake port, and it only evaluates a fixed location inside the equipment. In other words, it is not possible to properly estimate the particles that adhere to the substrate when the substrate is transported and processed inside the equipment, and it is not possible to properly evaluate whether the inside of the equipment is clean enough to process substrates.

[0043] In this embodiment, a regression model is defined by correlating the state of particles on the substrate when an operation in the apparatus (dummy operation) is performed with the count value of the particle counter of the air obtained from the multiple intake ports in the apparatus, and a weighting factor depending on the position of each intake port is obtained. Then, by using the weighting factor, the state of particles that will adhere to the substrate when the dummy operation is performed is estimated from the count value of the particles contained in the air obtained from each intake port. The cleanliness level in the apparatus can be appropriately evaluated based on the particle state of the dummy substrate estimated in this way.

[0044] Such a specific flow will be described with reference to the flowcharts of FIG. 7 and FIG. 8. FIG. 7 is a flowchart for explaining a flow for defining a regression model by correlating the state of particles on a substrate when an operation in the apparatus (dummy operation) is performed with the count value by a particle counter, and for calculating a weighting factor depending on the position of each intake port. FIG. 8 is a flowchart for explaining a flow for evaluating the cleanliness in the apparatus by using the weighting factor calculated in advance. If the weighting factor is calculated in advance using the flowchart shown in FIG. 7, the process in FIG. 8 can be performed as appropriate at a timing when the state in the apparatus is to be evaluated. Such an in-apparatus evaluation can be performed after the assembly, modification, and maintenance of the imprint apparatus to evaluate whether or not to permit the operation of the imprint apparatus. Each process in the flowcharts of FIG. 7 and FIG. 8 is realized by the control unit 50 controlling each part of the imprint apparatus 1.

[0045] In S1 of FIG. 7, the control unit 50 of the imprint apparatus 1 controls so as to obtain air at each position from each of the multiple intake ports 201 to 204. Then, in S2, the control unit 50 obtains numerical data of particles contained in the air obtained from the intake ports at each position. Furthermore, in S3, at the timing of obtaining the numerical data of the particles, an operation in the apparatus (dummy operation) simulating a normal imprint operation as much as possible is actually performed. Specifically, in the dummy operation, an operation of supplying resist to a substrate in the apparatus (referred to as a dispensing operation) and an operation of forming a pattern by imprinting and releasing (referred to as an imprint operation) are not actually performed. However, other than these operations, the same operations as the apparatus operation during device manufacture (referred to as a dummy dispensing operation and a dummy imprint operation) are repeated a predetermined number of times. Then, in S4, the particles attached to the substrate in the dummy operation of S3 are measured, and particle attachment data, which is the number of particles attached on the substrate, is obtained. Specifically, by counting the particles on the substrate using an external device, the count value can be obtained as particle adhesion data.

[0046] That is, S2 and S4 obtain numerical data of the particle counter of the air from each intake port and corresponding particle adhesion data on the substrate. The particle data from the particle counter is composed of information on time, number of counts, and particle diameter. The particle adhesion data on the substrate is composed of information on the number of particles, coordinates within the wafer surface, and particle diameter. The numerical data of the particle counter and the particle adhesion data are taken as one data set. By performing the processes of S1 to S4 n times (n=1 or more), n sets of this data set can be obtained. The greater the number of data sets, the more accurate the regression model, so n is set so that the processes of S1 to S4 are repeated in S5 to obtain a sufficient number of data sets.

[0047] In S6, the control unit 50 extracts feature amount data from the numerical data of the particle counter by a method described later in order to correlate the two data, and prepares data for a regression model. In S7, the control unit determines a weighting factor for each intake port using the data prepared in S6. The control unit stores the weighting factor determined in S7 in a storage means such as a memory in the device. This defines a regression model for the particle monitor.

[0048] The input data of the regression model is the feature data, and the response data is the particle adhesion data, and these data can be applied to the regression model. Depending on the position where the particles are monitored in the imprint apparatus, that is, the position of the air inlet, even if a large amount of particles are monitored, they may not adhere to the substrate, or even if a small amount of particles are monitored, they may adhere to the substrate. In other words, the influence of particles adhering to the substrate when the substrate is operated in a dummy operation varies depending on the position of the air inlet in the apparatus. Therefore, it is necessary to determine the weighting coefficient corresponding to each air inlet by an existing statistical method so that the error between the number of particles monitored by the particle counter and the number of particles adhering to the substrate due to the dummy operation is small. Therefore, if there are five air inlets, such as the air inlets 200 to 204 shown in FIG. 1(b), it is necessary to determine the weighting coefficient for each of the five air inlets.

[0049] The above flow makes it possible to determine the weighting coefficients for correlating the state of particles on the substrate when an operation in the equipment (dummy operation) is performed with the count value of the particle counter of the air obtained from the multiple intake ports in the equipment. Then, when the weighting coefficients of the regression model are stored as parameters in the equipment, it becomes possible to extract feature data from the data obtained from the particle counter and estimate the state of particles adhering to the substrate when the dummy operation is performed.

[0050] Next, a flow of estimating the state of particles adhering when a substrate is actually subjected to a dummy operation and evaluating the state inside the apparatus will be described with reference to Figure 8. Such processing in Figure 8 can be performed after the assembly, modification, and maintenance of the imprint apparatus, making it possible to monitor the cleanliness inside the apparatus. In addition, when the imprint apparatus is in an actual operating state for device manufacturing, the cleanliness inside the apparatus may be monitored by acquiring particle count data in real time.

[0051] In S11, the control unit 50 starts suctioning air from each of the multiple air intake ports 200 to 204. In S12, the control unit 50 causes the measurement unit 131 to measure and acquire the number of particles contained in the air sucked in through each suction port.

[0052] In S13, the control unit 50 obtains the weighting coefficient for each suction port stored in the memory in S8, and estimates the cleanliness level inside the device by multiplying the weighting coefficient by the number of particles contained in the air sucked through the corresponding suction port. Specifically, the state of particles that will adhere when the dummy operation is performed is estimated.

[0053] In S14, whether the cleanliness inside the apparatus is good is evaluated based on the cleanliness inside the apparatus estimated in S13, i.e., the state of particles that will likely adhere during the dummy operation. If the cleanliness is evaluated to be good in S14, it is determined in S15 that the apparatus can continue to operate and that the imprint operation can be continued. On the other hand, if a deterioration in cleanliness is recognized in S14 and there is a possibility that the mold will be damaged if the imprint operation is continued as is, it is determined that the imprint operation should be interrupted. If it is determined that the imprint operation should be interrupted, the control unit 50 may control the operation to automatically stop, or may notify the operator of an abnormal state.

[0054] By using the weighting coefficients in this way, the state inside the device can be correctly evaluated using the numerical values ​​of particles contained in the air from the intake port, without actually performing a dummy operation inside the device.

[0055] Next, the process described in FIG. 7 and FIG. 8 will be specifically described. The space in the imprint apparatus where particles may adhere to the substrate 101 is the space between the base plate 114 and the stage base 113, that is, the stage operation space (FIG. 1(b)). The outermost periphery of the substrate stage space is within the frame of the dotted line 119a shown in FIG. 1(b). The substrate stage 119 is located at various locations for imprint operation, dispensing operation, various calibration operations, substrate transfer operation with a substrate transport system (not shown), chuck maintenance operation, etc. Also, the frequency and duration of stay are significantly different for each operation. Therefore, at least one position for sucking air from the particle counter is required in this space, and five suction ports 200 to 204 are provided in this embodiment.

[0056] Figure 2(a) shows the numerical data (200a to 204a) of particles measured by measuring the air from five suction ports obtained in S2. ij (i represents the measurement location, and j represents the data set number).

[0057] Figure 2(b) shows the particles that adhered to the substrate during the dummy operation of S3. j (j represents the data set number). In other words, by carrying out S1 and S2, and S3 and S4, the numerical data of the particle is obtained as data set No.=1. dat 11 ,dat 21 ,dat 31 ,dat 41 ,dat 51 (Formula 1) and particle adhesion data on the substrate, P1 (formula 2) is obtained.

[0058] Next, in order to prepare the data for S6, in order to correlate the particle numerical data with the particle adhesion data, ijThe feature extraction from the above is described below. In this embodiment, as the simplest feature data, the numerical data of the particles is picked up at the timing when the count exceeds a threshold value, and the sum of the numerical data is used as the feature data. This is because, as a characteristic of the particle counter used as the measurement unit 131, there is a possibility of false counts occurring near the minimum measurement sensitivity. Furthermore, particles adhere to the substrate in many cases when some kind of dust generation event occurs in the substrate stage space, causing particles to drift in the space and adhere to the wafer, and in such cases the count value of the particle counter increases suddenly. Since there is a high possibility that such sudden dust generation is the cause of particles adhering to the substrate, a threshold value Th1 is set for the count data, and data dat' exceeding this threshold value is used as the feature data. ij The sum of the counts is defined as the feature data. This increases the reliability of the feature data. Σdata 11 ,Σdat′ 21 ,Σdat′ 31 ,Σdat′ 41 ,Σdat′ 51 (Formula 3) Since this feature amount data is considered to be correlated with the particle adhesion data P1 on the substrate, it is possible to define the following regression model. P1=V1*Σdat′ 11 +V2*Σdat′ 21 +…+V5*Σdata′ 51 +err1 (formula 4)

[0059] Expressed as a determinant,

[0060]

number

[0061] Here, each V i(i indicates the measurement location) indicates a weighting coefficient that depends on the measurement location. Using this regression model as a base, the processes from S1 to S4 are repeated n times in S5 to obtain No.=n data sets. That is, feature amount data is extracted from the numerical data of the particle counter in a similar manner, and particle adhesion data on the substrate is incorporated into this regression model.

[0062]

number

[0063] The more repetitions (n), the more accurate the regression model will be because the number of data sets increases. Then, the resulting data set is subjected to a statistical method, such as a regression analysis method such as the least squares method, to find the weighting coefficient V that minimizes the difference. i is estimated and determined.

[0064] S7 weighting factor V i Once determined, it is stored in the equipment's memory as a parameter of the regression model in S8. This regression model makes it possible to estimate the number of particles adhering to the substrate from the particle count data. In other words, even without actually performing a dummy operation inside the equipment, the condition inside the equipment can be correctly evaluated using the numerical value of the particles contained in the air from the intake port.

[0065] <Second embodiment> In the first embodiment, the particle count data dat ij In the above example, data exceeding a threshold is extracted as feature amount data extracted from the particle counter, and the sum of the count values ​​is used. In this embodiment, in order to deal with cases in which the data from the particle counter is discrete, an example is described in which the number of dust generation events that occurred in the substrate stage space is used as feature amount data. Note that in this embodiment, the same parts as in the first embodiment will not be described.

[0066] Figure 3(a) shows the numerical data (200a to 204a) of particles measured by measuring the air from five suction ports obtained in S2. ij (i represents the measurement location, and j represents the data set number).

[0067] Figure 3(b) shows the particles that adhered to the substrate during the dummy operation of S3. j (j represents the data set number).

[0068] In order to prepare the data for S6, we used the data set dat ij The extraction of feature quantities from the particle counter is described below. When the particle counter numerical data is discrete as shown in FIG. 3(a), it is considered that dust generation events also occur discretely. In such a case, the particle counter count value increases suddenly, so it is considered that there is a high correlation between the occurrence frequency and particle adhesion to the wafer. Therefore, in this embodiment, data exceeding a threshold value Th2 is picked up, and the number of occurrences N is calculated. ij (i is the measurement point, j is the data set number) is counted. Specifically, by defining the number of dotted lines as the feature data, the reliability of the feature data can be improved. In other words, from the count value of each suction port, N 11 ,N 12 ,N 13 ,N 14 ,N 15 (Formula 7) Since this feature amount data is considered to be correlated with the particle adhesion data P1 on the substrate, it is possible to define the following regression model. P1=W1*N 11 +W2*N 21 +…+W5*N 51 +err1 (formula 8)

[0069] Using this regression model as a base, the processes of S1 to S4 are repeated n times in S5 to obtain No.=n data sets. That is, feature amount data is extracted from the numerical data of the particle counter in a similar manner, and particle adhesion data on the substrate is incorporated into this regression model.

[0070]

number

[0071] The more iterations (n), the more accurate the regression model will be because the number of data sets increases. Then, the resulting data set is subjected to a statistical method, such as a regression analysis method such as the least squares method, to find the weighting coefficient W that minimizes the difference. i is estimated and determined.

[0072] S7 is the weighting factor W i Once determined, it is stored in the equipment's memory as a parameter of the regression model in S8. This regression model makes it possible to estimate the number of particles adhering to the substrate from the particle count data. In other words, even without actually performing a dummy operation inside the equipment, the condition inside the equipment can be correctly evaluated using the numerical value of the particles contained in the air from the intake port.

[0073] <Third embodiment> In this embodiment, an example will be described in which the particle count data once obtained is weighted by the degree of influence of adhesion to the substrate for each particle diameter, and this is used as feature amount data.

[0074] In general, the phenomenon of particles adhering to an object surface can be roughly explained by the following three physical quantities. The first physical quantity is the adhesion flux fdat (pcs / m^2·sec) that penetrates the adhesion surface per unit time and unit area. The second physical quantity is the particle number concentration dat (pcs / m^3) in the space near the adhesion surface. This is the same as the particle count data. The third physical quantity is the adhesion velocity vd (m / sec) of the particle to the target surface to which it adheres. These three physical quantities are related by Equation 10. fdat=vd×dat (Equation 10)

[0075] That is, if the particle adhesion velocity vd to the substrate surface and the particle count data dat are obtained in the substrate stage space, the adhesion flux fdat to the wafer can be calculated. Here, the particle adhesion velocity vd has already been studied in great numbers, and is described, for example, in Non-Patent Document 1 (Shimada Manabu, Mukosaka Yasuo: Aerosol Research, Vol. 3 No. 4, 273-282 (1988)). Non-Patent Document 1 shows a diagram of the particle deposition velocity (also called adhesion velocity) in a laminar flow field flowing parallel to the disk. It is assumed that the adhesion of particles to the substrate in the imprint apparatus shown in the present invention is also in a situation close to the situation disclosed in Non-Patent Document 1. Non-Patent Document 1 shows that the adhesion velocity is smaller in the vicinity of particle diameters of 0.1 to 0.2 μm, and that the particle diameters of less than 0.1 μm are one order of magnitude larger than this, and that the particle diameters of more than 0.2 μm are one to two orders of magnitude larger than this. In this way, it is known that the adhesion velocity vd varies greatly depending on the particle diameter. Therefore, in this embodiment, the particle count data is substituted into (Equation 10) and converted into the adhesion flux onto the substrate surface, thereby weighting the adhesion effect for each particle size.

[0076] The following explanation assumes that time-series data as shown in FIG. 4(a) and classification data by particle size as shown in FIG. 4(b) are obtained as particle count data. When such data is converted using (Equation 10), the time-series adhesion flux data fdat as shown in FIG. 4(a) becomes data as shown in FIG. 5(a), which is then acquired for each suction port and becomes data (200C to 204C) as shown in FIG. 6(a). Each data is converted into fdat ij (i represents the measurement location, and j represents the data set number). When the data classified by particle size as shown in Fig. 4(b) is converted, the data becomes as shown in Fig. 5(b). Fig. 6(b) shows the particles that adhered to the substrate during the dummy operation of S3, and the data on the number of particles adhered is P j (j represents the data set number).

[0077] When the adhesion flux is weighted for each particle size, the data values ​​of particles that adhere easily become larger and the data values ​​of particles that do not adhere easily become smaller in comparison, which means that the particle count data is converted into data that is closer to the actual adhesion phenomenon.

[0078] Next, the data fdat converted into the adhesion flux is used as the feature data of the particle count data. ij Take the sum of the above. That is, Σfdat 11 ,Σfdat 21 ,Σfdat 31 ,Σfdat 41 ,Σfdat 51 (Formula 11)

[0079] Since this feature data is considered to be correlated with the particle adhesion data P1 on the substrate, it is possible to define the following regression model. P1=Z1*Σfdat 11 +Z2*Σfdat 21 +…+Z5*Σfdat 51 +err1 (formula 12)

[0080] Using this regression model as a base, the processes of S1 to S4 are repeated n times in S5 to obtain No.=n data sets. That is, feature amount data is extracted from the numerical data of the particle counter in a similar manner, and particle adhesion data on the substrate is incorporated into this regression model.

[0081]

number

[0082] The more repetitions (n), the more accurate the regression model will be because the number of data sets increases. Then, the resulting data set is subjected to a statistical method, such as a regression analysis method such as the least squares method, to find the weighting coefficient Z that minimizes the difference. i is estimated and determined.

[0083] S7 weighting factor Z i Once determined, it is stored in the equipment's memory as a parameter of the regression model in S8. This regression model makes it possible to estimate the number of particles adhering to the substrate from the particle count data. In other words, even without actually performing a dummy operation inside the equipment, the condition inside the equipment can be correctly evaluated using the numerical value of the particles contained in the air from the intake port.

[0084] Although the preferred embodiments of the present invention have been described above, it goes without saying that the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist of the present invention. As an example of a substrate processing apparatus, an imprinting apparatus that forms (molds) an imprint material on a substrate using a mold to form a pattern on the substrate has been described, but the present invention is not limited to imprinting apparatuses.

[0085] For example, it is possible to apply the present invention to a planarization apparatus having a process of applying an imprint material onto a substrate having an uneven surface, imprinting a mold having a flat surface, irradiating the substrate with light, and then separating the mold.

[0086] An example of a lithography apparatus may be a projection exposure apparatus that forms a pattern by exposing a projected image of a mask onto a substrate via an optical system. It may also include manufacturing apparatuses that perform processes other than those performed by the lithography apparatus described above in the manufacture of products such as devices, such as a coating apparatus that coats a photosensitive medium on the surface of a substrate and a developing apparatus that develops a substrate onto which a pattern has been transferred.

[0087] Regarding the manufacture of goods The pattern of the cured material formed using the imprint apparatus 1 described above is used permanently on at least a part of various articles, or temporarily when manufacturing various articles.

[0088] The article is an electric circuit element, an optical element, a MEMS, a recording element, a sensor, a mold, etc. Examples of the electric circuit element include volatile or non-volatile semiconductor memories such as DRAM, SRAM, flash memory, and MRAM, and semiconductor elements such as LSI, CCD, image sensor, and FPGA. Examples of the mold include a mold for imprinting.

[0089] The pattern of the cured product is used as it is as at least a part of a component of the article, or is used temporarily as a resist mask, which is removed after etching or ion implantation in a substrate processing step.

[0090] Next, a method for manufacturing an article will be described with reference to Fig. 9, in which a pattern is formed on a substrate by an imprinting device, the substrate on which the pattern is formed is processed, and an article is manufactured from the processed substrate. First, as shown in Fig. 9(a), a substrate 1z such as a silicon wafer having a workpiece 2z such as an insulator formed on its surface is prepared, and then an imprinting material 3z is applied to the surface of the workpiece 2z by an inkjet method or the like. Here, a state in which the imprinting material 3z in the form of multiple droplets is applied onto the substrate is shown.

[0091] As shown in Fig. 9(b), the imprinting mold 4z is placed so that the side on which the concave-convex pattern is formed faces the imprinting material 3z on the substrate. As shown in Fig. 9(c), the substrate 1z to which the imprinting material 3z has been applied is brought into contact with the mold 4z, and pressure is applied. The imprinting material 3z fills the gap between the mold 4z and the workpiece 2z. When light is irradiated through the mold 4z in this state as energy for hardening, the imprinting material 3z hardens.

[0092] 9(d), after the imprint material 3z is cured, the mold 4z and the substrate 1z are separated, and a pattern of the cured product of the imprint material 3z is formed on the substrate 1z. In this cured product pattern, the recesses of the mold correspond to the protrusions of the cured product, and the protrusions of the mold correspond to the recesses of the cured product, i.e., the recessed and protruding patterns of the mold 4z are transferred to the imprint material 3z.

[0093] As shown in Fig. 9(e), when etching is performed using the pattern of the cured material as an etching-resistant mask, the portion of the surface of the workpiece 2z where there is no cured material or where only a thin layer remains is removed, forming a groove 5z. As shown in Fig. 9(f), when the pattern of the cured material is removed, an article having grooves 5z formed on the surface of the workpiece 2z can be obtained. Here, the pattern of the cured material is removed, but it may be used as an interlayer insulating film included in a semiconductor element or the like, that is, a component of an article, without being removed after processing.

[0094] The method for manufacturing an article also includes a step of forming a pattern on an imprint material supplied (applied) to a substrate using the above-mentioned imprint apparatus (imprint method), and a step of processing the substrate on which the pattern has been formed in the above step. Furthermore, the manufacturing method includes other well-known steps (oxidation, film formation, deposition, doping, planarization, etching, resist stripping, dicing, bonding, packaging, etc.). It can be said that the method for manufacturing an article of this embodiment is more advantageous than conventional methods in at least one of the performance, quality, productivity, and production cost of the article.

[0095] <Summary of the embodiment> The disclosure of this specification includes the following items.

[0096] (Item 1) A method for evaluating a substrate processing apparatus having a processing section for processing a substrate, comprising the steps of: sucking air from a plurality of intake ports provided in an area where a substrate stage that carries the substrate and moves within the apparatus operates; measuring particles contained in the air sucked through each of the plurality of suction ports; correcting the measurement results from each of the suction ports according to the position of the suction port; evaluating the state of the device according to the corrected measurement results from each suction port; The evaluation method according to claim 1,

[0097] (Item 2) an estimation step of estimating the number of particles that adhere to the substrate when the substrate is mounted on the substrate stage and a dummy operation is performed in the apparatus, based on the corrected measurement results from each suction port; 2. The evaluation method according to item 1, wherein the evaluating step evaluates based on the number of particles estimated in the estimating step.

[0098] (Item 3) 3. The evaluation method according to item 1 or 2, wherein the correcting step corrects the measurement results from each suction port using a weighting coefficient indicating a degree of influence of particle adhesion on the substrate depending on the position of the suction port.

[0099] (Item 4) The method further includes a step of acquiring a weighting factor indicating a degree of influence of particle adhesion on the substrate depending on a position of the suction port, 4. The evaluation method according to item 3, wherein the correction step uses the weighting coefficient acquired in the acquisition step.

[0100] (Item 5) 5. The evaluation method according to claim 4, wherein the acquiring step uses feature amount data extracted from time-series count data, which is the measurement result from each of the suction ports, as input data, and particle adhesion data on the substrate, which is acquired by actually mounting a substrate on the substrate stage and performing a dummy operation in the apparatus, as response data, to statistically acquire a weighting coefficient indicating the degree of influence of particle adhesion using a regression model.

[0101] (Item 6) 6. The evaluation method according to item 5, wherein the feature amount data of the input data is a sum of data showing a value equal to or greater than a threshold in the time-series count data that is the measurement result.

[0102] (Item 7) 6. The evaluation method according to item 5, wherein the feature data of the input data is the number of times a value equal to or greater than a threshold is shown in the time-series count data that is the measurement result.

[0103] (Item 8) 6. The evaluation method according to item 5, wherein the feature amount data of the input data is calculated based on data obtained by converting the time-series count data, which is the measurement result, into an amount of adhesion flux to a substrate that depends on particle diameter.

[0104] (Item 9) A step of processing a substrate using a substrate processing apparatus evaluated by the evaluation method according to any one of items 1 to 8; and processing the substrate processed in the above step, A method for manufacturing an article, comprising the steps of: manufacturing an article from the processed substrate;

[0105] (Item 10) A substrate processing apparatus having a processing section for processing a substrate, a substrate stage that carries the substrate and moves within the apparatus; a plurality of intake ports that are provided in an area where the substrate stage operates and that suck in air; a measuring unit that measures particles contained in the air sucked from each of the plurality of suction ports; a control unit that corrects the measurement results from each suction port measured by the measurement unit in accordance with the position of the suction port, and evaluates the state of the apparatus in accordance with the corrected measurement results from each suction port; A substrate processing apparatus comprising:

Claims

1. A method for evaluating a substrate processing apparatus having a processing section for processing a substrate, comprising the steps of: sucking air from a plurality of intake ports provided in an area where a substrate stage that carries the substrate and moves within the apparatus operates; measuring particles contained in the air sucked through each of the plurality of suction ports; correcting the measurement results from each of the suction ports according to the position of the suction port; evaluating the state of the device according to the corrected measurement results from each suction port; The evaluation method according to claim 1,

2. an estimation step of estimating the number of particles that adhere to the substrate when the substrate is mounted on the substrate stage and a dummy operation is performed in the apparatus, based on the corrected measurement results from each suction port; 2. The evaluation method according to claim 1, wherein the evaluating step evaluates based on the number of particles estimated in the estimating step.

3. 2. The evaluation method according to claim 1, wherein the correcting step corrects the measurement results from each of the suction ports using a weighting coefficient indicating a degree of influence of particle adhesion on the substrate depending on the position of the suction port.

4. The method further includes a step of acquiring a weighting factor indicating a degree of influence of particle adhesion on the substrate depending on a position of the suction port, 4. The evaluation method according to claim 3, wherein the correction step uses the weighting coefficient acquired in the acquisition step.

5. 5. The evaluation method according to claim 4, wherein the obtaining step uses, as input data, feature amount data extracted from time-series count data that is the measurement result from each of the measured suction ports, and uses, as response data, particle adhesion data on the substrate, which is obtained by actually mounting a substrate on the substrate stage and performing a dummy operation in the apparatus, to statistically obtain a weighting coefficient indicating the degree of influence of particle adhesion by using a regression model.

6. 6. The evaluation method according to claim 5, wherein the feature amount data of the input data is a sum of data that shows a value equal to or greater than a threshold value in the time-series count data that is the measurement result.

7. 6. The evaluation method according to claim 5, wherein the feature amount data of the input data is the number of times a value equal to or greater than a threshold is shown in the time-series count data that is the measurement result.

8. 6. The evaluation method according to claim 5, wherein the feature amount data of the input data is calculated based on data obtained by converting the time-series count data, which is the measurement result, into an amount of flux adhering to the substrate, which is dependent on particle diameter.

9. A step of processing a substrate using a substrate processing apparatus evaluated by the evaluation method according to any one of claims 1 to 8; and processing the substrate processed in the above step, A method for manufacturing an article, comprising the steps of: manufacturing an article from the processed substrate;

10. A substrate processing apparatus having a processing section for processing a substrate, a substrate stage that carries the substrate and moves within the apparatus; a plurality of intake ports that are provided in an area where the substrate stage operates and that suck in air; a measuring unit that measures particles contained in the air sucked from each of the plurality of suction ports; a control unit that corrects the measurement results from each suction port measured by the measurement unit in accordance with the position of the suction port, and evaluates the state of the apparatus in accordance with the corrected measurement results from each suction port; A substrate processing apparatus comprising:

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