Charged particle beam apparatus and rigidity degradation detection method

Abstract

It accurately detects the deterioration of the rigidity of equipment components while reducing downtime. [Solution] The charged particle beam apparatus comprises a chamber having a lens barrel housing an emission unit for emitting a charged particle beam, and a stage on which a substrate irradiated by the charged particle beam is placed, with the lens barrel connected to the upper surface. The charged particle beam apparatus comprises an excitation source for exciting the chamber, an output vibration sensor attached to the charged particle beam apparatus, an input vibration sensor disposed between the output vibration sensor and the excitation source, and a control device that calculates a transfer function based on the measurement results of the input vibration sensor and the output vibration sensor when excited by the excitation source, and determines whether or not there is a deterioration in the rigidity of a component disposed between the input vibration sensor and the output vibration sensor based on the transfer function.

Description

Technical Field

[0001] The present invention relates to a charged particle beam device and a method for detecting stiffness degradation.

Background Art

[0002] In order to draw a predetermined pattern on a semiconductor substrate such as a silicon wafer or to draw a predetermined pattern on a mask substrate used to expose a pattern on the semiconductor substrate, a drawing apparatus using a charged particle beam such as an electron beam is used. Further, in order to inspect defects in patterns formed on an object such as a mask substrate or a semiconductor substrate, an inspection apparatus that irradiates the object with a charged particle beam such as an electron beam and acquires an image of the object is used. [[ID=!13]]

[0003] In such charged particle beam devices such as drawing apparatuses and inspection apparatuses, stiffness degradation evaluation of mechanical components is necessary for predictive maintenance of component failures. Conventionally, a hammering test has been performed for predictive maintenance evaluation of assembled mechanical components. However, the hammering test takes a lot of time for preparation and the test itself, and the device cannot be operated during the test, resulting in a long downtime (device operation stop time). In addition, there were problems such as the input to the device changing depending on the operator who hits the device with an impact hammer, and the input not always being the same even by the same operator. Also, since time-series data measurement is not performed, it was difficult to determine whether stiffness degradation occurred or it was a state change due to component replacement in the hammering test of a single component to be measured.

[0004] Patent Document 1 describes a charged particle beam device that detects whether a component has a mechanical defect that affects the vibration of a charged particle beam without actual operation. However, since the method described in Patent Document 1 is an evaluation using a beam, it takes a waiting time until the beam is stably output. Also, it is not easy to distinguish between vibrations due to beam defects and vibrations due to mechanical defects in this method.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Patent No. 7292968 [Patent Document 2] Japanese Patent Application Publication No. 8-114525 [Patent Document 3] Japanese Patent Application Publication No. 9-101289 [Overview of the project] [Problems that the invention aims to solve]

[0006] This invention has been made in view of the above-mentioned conventional problems, and aims to provide a charged particle beam apparatus and a rigidity degradation detection method that can accurately detect rigidity degradation of apparatus components while shortening downtime. [Means for solving the problem]

[0007] A charged particle beam apparatus according to one aspect of the present invention comprises a chamber having a lens barrel housing an emission unit for emitting a charged particle beam, and a stage on which a substrate irradiated by the charged particle beam is placed, with the lens barrel connected to the upper surface of the chamber, and further comprising: an excitation source for exciting the chamber; an output vibration sensor attached to the charged particle beam apparatus; an input vibration sensor disposed between the output vibration sensor and the excitation source; and a control device that calculates a transfer function based on the measurement results of the input vibration sensor and the output vibration sensor when excited by the excitation source, and determines whether or not there is a deterioration in the rigidity of a component disposed between the input vibration sensor and the output vibration sensor based on the transfer function.

[0008] A method for detecting rigidity degradation according to one aspect of the present invention is a method for detecting rigidity degradation of a component of a charged particle beam apparatus, which comprises a chamber having a barrel housing an emission unit for emitting a charged particle beam, and a stage on which a substrate irradiated by the charged particle beam is placed, with the barrel connected to the upper surface, wherein the charged particle beam apparatus comprises an excitation source for exciting the chamber, an output vibration sensor attached to the charged particle beam apparatus, and an input vibration sensor positioned between the output vibration sensor and the excitation source, wherein the chamber is excited by the excitation source, measurement results from the input vibration sensor and the output vibration sensor attached to the charged particle beam apparatus so as to sandwich the component are obtained, a transfer function is calculated based on the measurement results from the input vibration sensor and the output vibration sensor, and the presence or absence of rigidity degradation of the component is determined based on the transfer function. [Effects of the Invention]

[0009] According to the present invention, it is possible to accurately detect the deterioration of the rigidity of equipment components while reducing downtime. [Brief explanation of the drawing]

[0010] [Figure 1] This is a plan view of an electron beam lithography apparatus according to an embodiment of the present invention. [Figure 2] This is a side view of an electron beam lithography system. [Figure 3] This figure shows an example of calculating a transfer function. [Figure 4] This figure shows an example of how the transfer function changes. [Figure 5] This figure shows an example of vibration sensor installation. [Figure 6] This figure shows an example of vibration sensor installation. [Figure 7] This figure shows an example of vibration sensor installation. [Figure 8] This figure shows an example of vibration sensor installation. [Figure 9] This figure shows an example of vibration sensor installation. [Figure 10] (a) and (b) are diagrams showing examples of vibration sensor installation. [Figure 11] (a) and (b) are diagrams showing installation examples of vibration sensors.

Embodiment for Carrying out the Invention

[0011] Hereinafter, embodiments of the present invention will be described based on the drawings.

[0012] FIG. 1 is a plan view of an electron beam lithography apparatus 1 (an example of a charged particle beam apparatus) according to an embodiment of the present invention, and FIG. 2 is a side view of a part of the electron beam lithography apparatus 1. For convenience of explanation, a part of the configuration shown in FIG. 2 is not shown in FIG. 1. Similarly, a part of the configuration shown in FIG. 1 is not shown in FIG. 2. As shown in FIGS. 1 and 2, the electron beam lithography apparatus 1 includes a substrate transfer system 10, an input / output (I / O) chamber 20, a robot chamber (R chamber) 30, a writing chamber (W chamber) 40, an electron beam column 50, a control device 60, a storage unit 70, a vibration isolation table 80, and gate valves G1 to G3. In the present embodiment, the writing chamber (W chamber) 40 and the electron beam column 50 correspond to the chamber and the column in the present invention, respectively.

[0013] Drawing data serving as layout data is input from the outside and stored in the storage unit 70. Further, transfer function data is stored in the storage unit 70. The transfer function data will be described later.

[0014] The substrate transfer system 10 has a transfer arm 11 that transfers the mask substrate M as a transfer mechanism, receives the mask substrate M from the outside, and transfers it to the I / O chamber 20 on the subsequent stage side while discharging the mask substrate M. Further, the substrate transfer system 10 discharges the mask substrate M while discharging the charged mask substrate M after drawing, and carries it out to the outside.

[0015] The I / O chamber 20 is a so-called load lock chamber for loading and unloading the mask substrate M while maintaining the inside of the R chamber 30 in a vacuum (low pressure). The I / O chamber 20 includes a vacuum pump 21 and a gas supply system 22, and a gate valve G1 is provided between it and the substrate transfer system 10. The vacuum pump 21 is, for example, a dry pump, a turbo molecular pump, or the like, and evacuates the inside of the I / O chamber 20. The gas supply system 22 supplies vent gas (for example, nitrogen gas or CDA) into the I / O chamber 20 when bringing the I / O chamber 200 to atmospheric pressure.

[0016] When evacuating the inside of the I / O chamber 20, evacuation is performed using the vacuum pump 21 connected to the I / O chamber 20. Also, when returning the inside of the I / O chamber 20 to atmospheric pressure, vent gas is supplied from the gas supply system 22, and the inside of the I / O chamber 20 becomes atmospheric pressure. Note that when evacuating and making the inside of the I / O chamber 20 atmospheric pressure, the gate valves G1, G2 are closed.

[0017] The R chamber 30 includes a vacuum pump 31, an alignment chamber 32, a mask cover storage chamber 33, and a transfer arm 34. The R chamber 30 is connected to the I / O chamber 20 via a gate valve G2.

[0018] The vacuum pump 31 is, for example, a cryopump, a turbo molecular pump, or the like. The vacuum pump 31 is connected to the R chamber 30 and evacuates the inside of the R chamber 30 to maintain a high vacuum. The alignment chamber 32 is a chamber for positioning (aligning) the mask substrate M.

[0019] The mask cover storage chamber 33 is a chamber for storing the mask cover H. The mask cover H has conductivity and is provided with a plurality of grounding mechanisms on a frame-shaped body having an opening at the center. The size of the frame is slightly larger than that of the mask substrate M. The mask cover H is for discharging the charge accumulated on the mask substrate M by irradiation with an electron beam.

[0020] The transport arm 34 transports the mask substrate M between the I / O chamber 20, the alignment chamber 32, the mask cover storage chamber 33, and the W chamber 40. The temperature of the transport arm 34 in the R chamber 30 and the temperature inside the W chamber 40 are maintained at predetermined temperatures by a constant temperature means (not shown) using constant temperature water or the like.

[0021] The W chamber 40 (drawing chamber) is equipped with a vacuum pump 41, an XY stage 42, and drive mechanisms 43A and 43B, and is connected to the R chamber 30 via a gate valve G3.

[0022] The vacuum pump 41 is, for example, a cryopump or a turbomolecular pump. The vacuum pump 41 is connected to the W chamber 40 and maintains a high vacuum by evacuating the W chamber 40. The XY stage 42 is a platform on which the mask substrate M is placed. The drive mechanism 43A drives the XY stage 42 in the X direction (the scanning direction of the XY stage 42). The drive mechanism 43B drives the XY stage 42 in the Y direction. The processing in chambers 10, 20, 30, and 40, as well as the opening and closing of gate valves G1, G2, and G3, are controlled by the control device 60.

[0023] As shown in Figure 2, an electron beam tube 50 is connected to the upper surface of the W chamber 40. The electron beam tube 50 houses an electron beam irradiation mechanism (not shown) consisting of an electron gun (emitting part) that emits an electron beam, a deflector, lenses, etc. The control device 60 controls the electron beam irradiation mechanism using drawing data and irradiates the mask substrate M placed on the XY stage 42 with the electron beam to draw the desired pattern. A mask cover H is set on the mask substrate M to which the electron beam is irradiated, but the mask cover H is not shown in Figure 2.

[0024] A vibration isolation table 80 is provided on the underside of the W chamber 40. The vibration isolation table 80 has multiple actuators (not shown) and generates a suppression force that cancels out vibration forces in the X-axis direction that occur when the XY stage 42 accelerates and decelerates in the X-axis direction, and a suppression force that cancels out vibration forces acting perpendicular to the direction of movement of the XY stage 42, thereby suppressing lateral shaking of the W chamber 40 and the electron beam tube 50. The operation of the actuators is controlled by a control device 60.

[0025] In the electron beam lithography apparatus 1, for example, deterioration of the rigidity of components of the W chamber 40 and electron beam tube 50 can affect beam vibration and reduce lithography accuracy. Therefore, it is necessary to evaluate the rigidity deterioration of the components. In this embodiment, vibration sensors are placed so as to sandwich one or more components to be evaluated, and the gate valve G3 connected to the W chamber 40 is used as the excitation source. The transfer function is calculated and recorded from the vibration measurement results of the vibration sensors. Measurements are performed multiple times at predetermined time intervals or predetermined timings, and rigidity deterioration is detected from the change in the transfer function.

[0026] Furthermore, the excitation source includes not only the excitation source that uses components used in the original series of operations of the electron beam lithography apparatus 1 (in short, components necessary for transporting the substrate and drawing a circuit pattern on the mask substrate with an electron beam in a vacuum environment) to detect the deterioration of the rigidity of the components of the electron beam lithography apparatus 1, but also excitation sources that generate vibrations solely for the purpose of detecting the deterioration of the rigidity of the components of the electron beam lithography apparatus 1.

[0027] It is preferable to install the input vibration sensor u at a location with higher rigidity (or a higher natural frequency) than the gate valve G3 (more specifically, the housing of the gate valve G3). For example, as shown in Figures 1 and 2, the input vibration sensor u is installed on the upper surface of the W chamber 40. By installing the input vibration sensor u on the upper surface of the W chamber 40 at the end in the Y-axis direction (in other words, near the gate valve G3), it becomes easier to detect vibrations of the gate valve G3.

[0028] However, by not placing the input vibration sensor u on the gate valve G3 itself, the input vibration sensor u is less affected by the opening and closing motion of the gate valve G3 (unidirectional motion), the rotational moment of the gate valve G3 (rotational motion of the entire gate valve G3 due to the impact during opening and closing which is the source of vibration), and deflection. As a result, the signal accuracy of the input vibration sensor u is improved, and a more accurate transfer function can be calculated.

[0029] Furthermore, by installing the input vibration sensor u in the center of the X direction, which is the stage movement direction during pattern drawing (scanning direction of the XY stage 42), it is possible to reduce the influence of the rotational motion of the W chamber 40 around the Y axis passing through the center of gravity of the W chamber 40. Here, the position where the input vibration sensor u is located is the same position in the X direction as the position where the gate valve G3, which is the excitation source, is located. Moreover, "same position" is not limited to the center of the input vibration sensor u and the center of the gate valve G3 being exactly the same in the X direction, but also includes, for example, the input vibration sensor u being located within the range in which the housing of the gate valve G3 extends in the X direction.

[0030] The output vibration sensor y1, along with the input vibration sensor u, is installed in a position that sandwiches the component whose rigidity degradation is to be detected (for example, the electron beam tube 50). More specifically, the components are arranged in the following order: gate valve G3, input vibration sensor u, electron beam tube 50, and output vibration sensor y1. The output vibration sensor y1 is attached to a component whose vibration directly affects beam accuracy. For example, the output vibration sensor y1 is installed on the top surface of the electron beam tube 50. This is because the top surface of the electron beam tube 50 is susceptible to vibrations from the gate valve G3. In Figure 1, the output vibration sensor y1 is placed in the center of the top surface of the electron beam tube 50, but installing it at the edge of the top surface makes it easier to detect larger vibrations.

[0031] The control device 60 includes a vibration control unit 61, a vibration acquisition unit 62, a transfer function calculation unit 63, and a determination unit 64. Each part of the control device 60 may be composed of hardware such as electrical circuits, or it may be composed of software such as programs that perform these functions. If it is composed of software, the programs that realize these functions may be stored on a recording medium and loaded into a computer including electrical circuits and executed.

[0032] The vibration control unit 61 causes the gate valve G3 to open and close, thereby vibrating the electron beam lithography apparatus 1 (W chamber 40, electron beam tube 50, etc.).

[0033] The vibration acquisition unit 62 acquires the vibration measurement results of the input vibration sensor u and the output vibration sensor y1 when the gate valve G3 is excited.

[0034] As shown in Figure 3, the transfer function calculation unit 63 calculates a transfer function that shows the relationship between the input signal and the output signal, using the measurement result of the input vibration sensor u as the input signal and the measurement result of the output vibration sensor y1 as the output signal. The calculated transfer function is stored as transfer function data in the storage unit 70.

[0035] The determination unit 64 compares the calculated transfer function with past transfer functions stored in the memory unit 70 to determine whether or not the rigidity of the member has deteriorated. This will be explained using Figure 4. Figure 4 shows frequency on the horizontal axis and gain on the vertical axis. For example, the left figure shows the member before the rigidity changes, and the right figure shows the graph after the rigidity of the member has changed (the dotted line shows the state of the member before the rigidity changed in the left figure). There are two peak frequencies in the right figure; the higher frequency indicates a decrease in gain, and the lower frequency indicates a shift to an even lower value. These changes allow for the determination that the rigidity of the member has deteriorated. In other words, if the peak frequency of the transfer function changes or the gain changes, it can be determined that the rigidity of the member has deteriorated.

[0036] If it is determined that the rigidity of the component located between the input vibration sensor u and the output vibration sensor y1 has deteriorated, the component will be replaced, the mounting method of the component will be modified, or additional investigations will be conducted.

[0037] In this embodiment, the gate valve G3, a component of the electron beam lithography apparatus 1, is used as an excitation source. Impulse excitation caused by the opening and closing operation of the gate valve G3 during a series of operations of the electron beam lithography apparatus 1 is used to detect the deterioration of the rigidity of the component. This not only facilitates the detection of the deterioration of the component's rigidity but also reduces the downtime of the electron beam lithography apparatus 1. Furthermore, since the input vibration of the gate valve G3 is constant, the deterioration of the component's rigidity can be detected based on the change in the transfer function over time.

[0038] In the above embodiment, an example in which one output vibration sensor y1 is installed was described, but two or more may be installed. In the embodiment shown in Figures 5 to 9, two output vibration sensors y1 and y2 are arranged. Output vibration sensors y1 and y2 correspond to the first output vibration sensor and the second output vibration sensor in the present invention, respectively. Figures 5 to 9 mainly describe the second output vibration sensor (output vibration sensor y2). Unless otherwise specified, Figures 5 to 9 have the same configuration as Figures 1 and 2.

[0039] For example, as shown in Figure 5, an output vibration sensor y2 may be installed at the end of the vacuum piping 90. The vacuum piping 90 has one end of a straight main pipe connected to the side of the electron beam tube 50, and the other end connected to the vacuum pump 91. The vacuum piping 90 also branches upward and is connected to the side of the electron beam tube 50. The vacuum piping 90 and the W chamber 40 are connected via a support base 95. The vacuum piping 90 is a component that is easily affected by vibrations of the electron beam tube 50 to which the output vibration sensor y1 is attached.

[0040] The vibration acquisition unit 62 acquires measurement results from the output vibration sensor y2. The transfer function calculation unit 63 uses the measurement result of the input vibration sensor u as the input signal and the measurement result of the output vibration sensor y2 as the output signal to calculate a transfer function that shows the relationship between the input signal and the output signal. The determination unit 64 compares the calculated transfer function with, for example, past transfer functions stored in the memory unit 70 to determine whether or not there is a deterioration in the rigidity of the member located between the input vibration sensor u and the output vibration sensor y2. The past transfer functions stored in the memory unit 70 may be transfer functions obtained during the previous operation of the electron beam lithography apparatus 1, or they may be transfer functions obtained from earlier operation of the electron beam lithography apparatus 1, not limited to the previous operation.

[0041] As shown in Figure 6, the output vibration sensor y2 may be installed in the vacuum piping 90 near the electron beam tube 50. Figures 5 and 6 show the case where the output vibration sensor y2 is placed in the vacuum piping 90 near the vacuum pump 91 and near the electron beam tube 50, respectively, but it is not limited to these locations, and may be placed in other locations such as the center of the vacuum piping 90.

[0042] In Figure 5, by positioning the output vibration sensor y2 at a distance from the electron beam tube 50 (in other words, at a position close to the vacuum pump 91 of the vacuum piping 90), the output vibration sensor y2 can detect not only the vibration of the gate valve G3 transmitted from the electron beam tube 50, but also the vibration of the gate valve G3 transmitted from the W chamber 40 to the vacuum pump 91. In contrast, in Figure 6, by positioning the output vibration sensor y2 closer to the electron beam tube 50, compared to the arrangement of the output vibration sensor y2 in Figure 5, the output vibration sensor y2 is less affected by the vibration of the gate valve G3 transmitted from the W chamber 40 to the vacuum pump 91, and more easily affected by the vibration of the gate valve G3 transmitted from the electron beam tube 50.

[0043] As shown in Figure 7, the output vibration sensor y2 may be attached to the side of the electron beam tube 50. This makes it possible to more clearly detect which of the components constituting the electron beam tube 50 is experiencing rigidity degradation.

[0044] Furthermore, since the vibrations of the vacuum pumps 91, 92, and 93 are very small, their vibrations do not substantially affect the measurement of the gate valve G3's vibration. However, as shown in Figures 8 and 9, by placing output vibration sensors y2 on the vacuum pumps 91, 92, and 93, the effect of the vacuum pumps' vibrations can be measured, allowing for more accurate measurement of the gate valve G3's vibration. As a result, components experiencing rigidity degradation can be detected more clearly. The diagram showing the configuration with the output vibration sensor y2 on the vacuum pump 93 is omitted. The embodiments shown in Figures 8 and 9 will be described in detail below.

[0045] As shown in Figure 8, the output vibration sensor y2 may be installed on the vacuum pump 91. By attaching the output vibration sensor y2 to the heavy vacuum pump 91, large vibrations can be obtained. This makes the vibration of the vacuum pump 91 clearer, and the influence of the vacuum pump 91 on the electron beam tube 50 and vacuum piping 90, which are mainly detected by the output vibration sensor y1, can be clearly identified, and components experiencing rigidity degradation can be detected more clearly. The output vibration sensor y2 may be attached to the top surface or the side surface of the vacuum pump 91.

[0046] As shown in Figure 9, an output vibration sensor y2 may be attached to the vacuum pump 92 connected to the upper side of the electron beam tube 50. In Figure 9, the output vibration sensor y2 is placed on the vacuum pump 92, but the output vibration sensor y2 may also be attached to the vacuum pump 93, or to both vacuum pumps 92 and 93. This makes the vibrations of the vacuum pumps 92 and 93 clearer, and makes the effects of the vacuum pumps 92 and 93 on the electron beam tube 50 and vacuum piping 90, which are mainly detected by the output vibration sensor y1, clearer, and makes it possible to more clearly detect members where rigidity degradation is occurring.

[0047] In Figures 5 to 9, the placement position of the output vibration sensor y2 is changed in each case, but these placement positions of the output vibration sensor y2 may be combined and used. For example, the placement positions of the output vibration sensor y2 shown in Figures 5 and 6 may be combined so that the output vibration sensor y2 is placed both near the vacuum pump 91 of the vacuum piping 90 and near the electron beam tube 50.

[0048] The output vibration sensor y2 can be attached to gas discharge sections such as the vacuum piping 90, vacuum pump 91, vacuum pumps 92 and 93, vacuum piping 96 connecting vacuum pump 92 and the electron beam tube 50, and vacuum piping 97 connecting vacuum pump 93 and the electron beam tube 50.

[0049] The input vibration sensor u can be mounted closer to the excitation source than the output vibration sensors y1 and y2, and the mounting location is not limited to Figure 1. For example, as shown in Figures 10(a) and 10(b), the input vibration sensor u may be mounted on the upper surface of the W chamber 40 at the end in the X direction and in the center in the Y direction. This is suitable when it is desired to measure the effect of rotational motion of the W chamber 40 accompanying stage movement (more specifically, rotational motion about the Y axis passing through the center of gravity of the W chamber 40).

[0050] As shown in Figures 11(a) and 11(b), the input vibration sensor u may be mounted on the upper surface of the W chamber 40, near the lower end of the electron beam tube 50. This is suitable when it is desired to clearly measure the vibration of the electron beam tube 50. In this embodiment, by installing the input vibration sensor u in the center in the X direction, it is possible to reduce the influence of rotational motion of the W chamber 40 about the Y axis passing through the center of gravity of the W chamber 40.

[0051] In the X direction, it is preferable that the mounting position of the input vibration sensor u and the center of gravity of the W chamber 40 are the same. Here, the center of gravity of the W chamber 40 is the center of gravity of the W chamber 40 when it is installed in the electron beam lithography apparatus 1, which is in a state where a desired pattern can be drawn on the substrate W. More specifically, as shown in Figure 1, the W chamber 40 is equipped with a vacuum pump 41, a drive mechanism 43A, a drive mechanism 43B, an electron beam tube 50, and a gate valve G3, and is installed in the electron beam lithography apparatus 1, which is equipped with a substrate transport system 10, an input / output (I / O) chamber 20, and a robot chamber (R chamber) 30, which are located in the -Y direction of the gate valve G3.

[0052] Furthermore, "identical" does not only refer to cases where the mounting position of the input vibration sensor u and the center of gravity of the W chamber 40 are exactly the same, but also includes cases where both positions are approximately the same, based on the intention to reduce the influence of rotational motion of the W chamber 40 about the Y axis passing through the center of gravity of the W chamber 40.

[0053] In all of the embodiments described above, an example was given in which the gate valve G3 is used as the excitation source. However, the excitation source is not limited to the gate valve G3, but can be any device incorporated into the electron beam lithography apparatus 1 that can generate vibrations and control those vibrations. For example, the gate valve G2 or the gate valve G1 can be used as the excitation source.

[0054] Furthermore, in any of the embodiments described above, the XY stage 42 may be used as an excitation source. By driving the drive mechanisms 43A and 43B and controlling the acceleration and deceleration of the XY stage 42, various vibrations can be applied. More specifically, the amplitude and frequency of the vibrations can be adjusted.

[0055] Furthermore, when the XY stage 42 is used as the excitation source, the drive mechanisms 43A and 43B move the XY stage 42 in the X direction and / or Y direction (see Figure 1), providing vibrations with arbitrary amplitude and frequency. This allows for obtaining a more accurate transfer function than when the gate valve G3 is used as the excitation source. For example, the XY stage 42 can be operated with a sine sweep (a signal used to obtain a frequency response function by repeating the same measurement while changing the frequency of the input sine wave) to obtain a more accurate transfer function. Therefore, for example, the gate valve G3, which has a short town time, can be used as the excitation source under normal circumstances to diagnose periodic deterioration of the rigidity of the members. When it is necessary to diagnose detailed deterioration of the rigidity of the members, the XY stage 42 can be used as the excitation source. .

[0056] Alternatively, the vibration isolation table 80 may be used as an excitation source. By controlling multiple actuators (not shown) of the vibration isolation table 80, vibrations can be applied to the electron beam lithography apparatus 1.

[0057] In the above embodiment, an example was described in which the presence or absence of rigidity deterioration is determined based on the change in the transfer function over time. However, the transfer function when a failure or other trouble occurred in the past may be recorded, and the similarity between that transfer function and the calculated transfer function (for example, a state in which the waveform patterns of the transfer function shown in Figure 3 are similar) may be determined at a predetermined period. If the transfer functions are similar, it becomes possible to take preventative measures against trouble. Note that the transfer function when a failure or other trouble occurred in the past may be calculated not only from the control device 60 of the same electron beam lithography apparatus 1, but also from data obtained from other electron beam lithography apparatus 1 with the same configuration.

[0058] If there are multiple components between the input vibration sensor u and the output vibration sensor y1, and each component exhibits characteristic changes in the transfer function when its rigidity deteriorates, then characteristic information may be stored in the memory unit 70 to determine which component's rigidity has deteriorated. For example, characteristic information such as a decrease in the peak frequency of the transfer function when component P1 deteriorates in rigidity, or a decrease in the gain of the transfer function when component P2 deteriorates in rigidity, may be stored in the memory unit 70.

[0059] In the above embodiment, an electron beam configuration was described as an example of a charged particle beam. However, the charged particle beam is not limited to an electron beam; it may also be a beam using charged particles such as an ion beam.

[0060] In the above embodiment, an electron beam lithography apparatus 1 for drawing patterns on a substrate was described, but it can be applied to semiconductor manufacturing equipment using charged particle beams, and can also be applied to other irradiation devices that irradiate an object with a beam, such as inspection equipment.

[0061] It should be noted that the present invention is not limited to the embodiments described above, and the components can be modified and implemented in practice without departing from the spirit of the invention. Furthermore, various inventions can be formed by appropriately combining the multiple components disclosed in the above embodiments. For example, some components may be deleted from all the components shown in the embodiments. Moreover, components from different embodiments may be appropriately combined. [Explanation of symbols]

[0062] 40 Lighting Chambers 42 XY Stages 50 Electron beam tube 80 Vibration isolation table G1-G3 Gate Valves u Input vibration sensor y1, y2 Output vibration sensors

Claims

1. A charged particle beam apparatus comprising a chamber having an emission unit for emitting a charged particle beam housed in a microscope tube, and a stage on which a substrate to which the charged particle beam is irradiated is placed, with the microscope tube connected to the upper surface, An excitation source for exciting the chamber, An output vibration sensor attached to the charged particle beam apparatus, An input vibration sensor is positioned between the output vibration sensor and the excitation source, A control device that calculates a transfer function based on the measurement results of the input vibration sensor and the output vibration sensor when the vibration source is used for excitation, and determines whether or not there is a deterioration in the rigidity of a component placed between the input vibration sensor and the output vibration sensor based on the transfer function, A charged particle beam device equipped with the following features.

2. The charged particle beam apparatus according to claim 1, wherein the input vibration sensor is mounted on the upper surface of the chamber.

3. The charged particle beam apparatus according to claim 1, wherein, in the scanning direction of the stage, the mounting position of the input vibration sensor and the center of gravity of the chamber are the same.

4. The charged particle beam apparatus according to claim 2, wherein the input vibration sensor is attached to a location with higher rigidity than the excitation source.

5. The charged particle beam apparatus according to claim 1, wherein the output vibration sensor is attached to the microscope tube.

6. The charged particle beam apparatus according to claim 5, wherein the output vibration sensor is mounted on the upper surface of the microscope tube.

7. The charged particle beam apparatus according to claim 1, wherein the excitation source comprises a controllable drive source and is a mechanism used in the work process of the charged particle beam apparatus.

8. The charged particle beam apparatus according to claim 1, wherein the stage is an XY stage that can move in the X direction and the Y direction, and the XY stage is the excitation source.

9. The charged particle beam apparatus according to claim 1, wherein the excitation source is a gate valve connected to the chamber.

10. The aforementioned stage is an XY stage that can move in the X and Y directions, The charged particle beam apparatus according to claim 9, wherein the input vibration sensor is located on the upper surface of the chamber at the same position as the position where the excitation source is located in the X direction, and is attached to the end on the side where the excitation source is located in the Y direction.

11. The lens barrel is further equipped with a gas discharge section connected to its side surface. The aforementioned output vibration sensor includes a first output vibration sensor and a second output vibration sensor. The first output vibration sensor is attached to the lens barrel. The charged particle beam apparatus according to claim 1, wherein the second output vibration sensor is attached to the gas discharge section.

12. The gas discharge section comprises a vacuum pump and a vacuum pipe, one end of which is connected to the vacuum pump and the other end of which is connected to the side of the lens barrel. The charged particle beam apparatus according to claim 11, wherein the second output vibration sensor is attached to the vacuum piping.

13. A method for detecting rigidity degradation of a component of a charged particle beam apparatus, comprising a chamber having a barrel housing an emission unit for emitting a charged particle beam, and a stage on which a substrate irradiated by the charged particle beam is placed, with the barrel connected to the upper surface of the chamber, wherein the apparatus includes a chamber, The charged particle beam apparatus is An excitation source for exciting the chamber, An output vibration sensor attached to the charged particle beam apparatus, An input vibration sensor is positioned between the output vibration sensor and the excitation source, Equipped with, The chamber is vibrated by the vibration source, The measurement results of the input vibration sensor and the output vibration sensor, which are attached to the charged particle beam apparatus so as to sandwich the aforementioned component, are obtained. Based on the measurement results of the input vibration sensor and the output vibration sensor, the transfer function is calculated. A method for detecting stiffness degradation, which determines whether or not the stiffness of the component has deteriorated based on the transfer function.

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