Disturbance compensation for charged particle beam devices

Abstract

Charged particle beam devices (e.g., for repair tasks) may be disturbed. For example, when performing a manipulation mode for repairing defects on a lithographic mask, sensor outputs of one or more sensors are used to compensate for the perturbations.

Description

[0001] priority

[0002] This application claims priority to German Patent Application No. 10 2022 124 686.8 (filed on September 26, 2022), the disclosure of which is incorporated herein by reference. Technical Field

[0003] Various embodiments of the present invention generally relate to a charged particle beam apparatus and an operating method for a charged particle beam apparatus. Various embodiments specifically relate to disturbance compensation during operation of a charged particle beam apparatus. Background Art

[0004] Charged particle beam devices can be used for microscopy or, for example, the manipulation of semiconductor structures. Charged particles that can be used for charged particle beam devices include: electrons, positrons, muons, and ions. Examples of charged particle beam devices include: scanning electron microscopes (SEMs), focused ion beam (FIB) devices, SEMs with multiple beams, sometimes also called multi-SEMs.

[0005] For example, JP 2004-079334 discloses an electron beam device such as an electron microscope and an electron beam lithography device, which is equipped with a semiconductor electron beam detector for detecting an electron beam. A plurality of electron beam sensors are arranged on opposite sides of a mounting substrate, so that the semiconductor electron beam detector can be replaced more easily when the semiconductor electron beam detector is replaced.

[0006] The image of the object can be recorded using a particle microscope. In this way, for example, the structure of the surface can be analyzed (inspection mode). In addition, the sample can be modified, for example, by removing material or by depositing material (manipulation mode). For example, a charged particle beam device can be used to modify / manipulate a photolithography mask. Then, a charged particle beam device is sometimes referred to as a repair device. Examples of such repair devices are disclosed in US20200912914, the contents of which are incorporated herein by reference.

[0007] US2018 / 0277361 A1 discloses a method for depositing a material on a sample, the method comprising directing a charged particle beam toward a substrate to cause a protective layer to be deposited from a precursor gas over a region of interest. The protective layer may be a composite mixture of materials, the array of spots of which substantially matches the array of spots of the substrate.

[0008] Typically, disturbances lead to irregularities in the operation of a charged particle beam device. External disturbances, for example from varying temperature, pressure, vibrations, etc., often affect the beam positioning of a particle beam of a charged particle beam device relative to a sample stage.

[0009] Closed-loop control for compensating beam deviation is not always possible, because during operation in the inspection or manipulation mode, measuring the beam deviation of the charged particle beam is not possible or is only possible to a limited extent. Feed-forward compensation of individual disturbances is known in the prior art. This is explained below.

[0010] For example, JP 2003173755 discloses a charged particle beam device comprising an active magnetic field source configured to eliminate disturbances caused by an external magnetic field.

[0011] The technique disclosed in 2003173755 only achieves inadequate compensation for placement offset.

[0012] US 3842272 discloses a scanning charged particle microprobe system. A beam scans a sample in a predetermined pattern. Stray external electric and magnetic fields can be compensated by applying a beam correction signal to the beam scanning device. Again, using such techniques as disclosed in US 3842272, only inadequate compensation for placement offsets caused by such stray external electric and magnetic fields is achieved.

[0013] US 6,043,490 discloses a charged particle beam device, which includes means for separately detecting x and y components in mechanical vibration, and means for correcting x and y scanning signals to eliminate the influence of mechanical vibration. The technology of US 6,043,590 only produces limited ability to compensate for beam placement deviation of the charged particle beam device caused by disturbance.

[0014] US 9,601,310 discloses a charged particle microscope including an air pressure sensor. A control program is used to compensate for the relative position error between the charged particle beam and the sample holder based on the sensor signal from the air pressure sensor. Using the technology disclosed in US 9601310, only limited accuracy can be achieved when compensating for the placement offset caused by disturbances.

[0015] US 4698503 discloses a refocusing apparatus for a transmission electron microscope, the apparatus being operable to process electron beam sensor output signals at discrete illumination angles. Summary of the invention

[0016] Therefore, advanced technology is needed to compensate for beam deviation of a beam of a charged particle beam device on a sample stage caused by multiple disturbances. Therefore, as the requirements for resolution continue to increase, advanced technology is needed to compensate for beam aberration of beam blurring of a beam of a charged particle beam device caused by multiple disturbances.

[0017] This object is met by the features of the independent claims, while the features of the dependent claims define specific embodiments.

[0018] According to an example, a charged particle beam device includes a beam source, a beam deflection unit, and a sample stage.

[0019] In some examples, the charged particle beam device implements a charged particle beam repair device, in which case the charged particle beam repair device further includes a precursor gas source. The precursor gas source includes a gas supply located near the sample stage, a supply valve, and a supply nozzle. Sometimes, the charged particle beam repair device may include multiple precursor gas sources to supply different types of precursor gases.

[0020] The beam deflection unit is configured to deflect a beam of charged particles, such as electrons or ions, to position the beam on the sample stage.

[0021] The charged particle beam repair apparatus includes a plurality of sensors configured to measure a plurality of perturbations of a plurality of physical quantities, each physical quantity affecting a beam deviation of the beam on the sample stage.

[0022] The charged particle beam repair device also includes at least one control unit, such as a microprocessor or processor configured to execute program code loaded from the memory. Embedded electronic devices can be used. Field programmable gate arrays (FPGAs) can be used to implement the control unit.

[0023] The at least one control unit has the various tasks of beam control and process control.

[0024] The at least one control unit may also process sensor outputs provided by the plurality of sensors to determine one or more compensation signals to counteract beam deviation.

[0025] In some instances, such as when a manipulation mode is executed to complete a sample repair task, the at least one control unit is further configured to provide control signals to the beam source, the beam deflection unit, and the precursor gas source to implement electron beam induced manipulation of the sample mounted on the sample stage.

[0026] The at least one control unit is configured to provide one or more compensation signals to or around at least one of the beam source, the beam deflection unit, a sample stage of a charged particle beam repair device or one or more compensator modules, e.g. during the electron beam induced manipulation or when operating in an imaging mode.

[0027] This technique can reduce or fully compensate for disturbances during operation of a charged particle beam device, such as when operating in an imaging mode or a manipulation mode. For example, a semiconductor mask may undergo one or more repair tasks in the manipulation mode. By reducing or compensating for disturbances when performing manipulation, damage to the mask may be avoided.

[0028] A method for manipulating a sample mounted to a sample stage of a charged particle beam repair device is disclosed herein. The charged particle beam repair device includes a beam source, a beam deflection unit, a precursor gas source, and the sample stage. The beam deflection unit is configured to deflect a beam of charged particles originating from the beam source to position the beam on the sample stage. The method includes obtaining sensor outputs of multiple sensors of the charged particle beam repair device. The multiple sensors measure multiple disturbances of multiple physical quantities, each of which affects the beam deviation of the beam on the sample stage. The method also includes determining one or more compensation signals based on the sensor outputs of the multiple sensors to offset the beam deviation. The method also includes providing control signals to the beam source, the beam deflection unit, and the precursor gas source to implement electron beam induced manipulation of the sample. The method further includes providing one or more compensation signals to at least one of the beam source, the beam deflection unit, the sample state, or the one or more compensator modules during the electron beam induced manipulation.

[0029] The computer program or computer program product or computer readable storage medium comprises program code. The program code can be loaded and executed by at least one processor. The at least one processor is configured to perform the method of manipulating a sample when loading and executing the program code.

[0030] In some instances, the charged particle beam device includes a beam source, a beam deflection unit and a sample stage. The beam deflection unit is configured to deflect a beam originating from the beam source to position the beam on the sample stage. The charged particle beam device includes a plurality of sensors configured to measure a plurality of disturbances of a plurality of physical quantities, wherein each physical quantity affects a beam offset of the beam on the sample stage. The at least one control unit is configured to determine metadata indicating one or more compensation operations based on sensor outputs of the plurality of sensors to offset the beam offset in imaging data acquired by the charged particle beam repair device operating in imaging mode. The metadata may be stored in association with the image data.

[0031] A method for post-processing image data acquired by a charged particle beam device is disclosed herein. The charged particle beam device includes a beam source, a beam deflection unit and a sample stage. The beam deflection unit is configured to deflect a beam originating from the beam source to position the beam on the sample stage. The method includes obtaining sensor outputs of multiple sensors of the charged particle beam device. The multiple sensors measure multiple disturbances of multiple physical quantities, each of which affects the beam offset of the beam on the sample stage. The method also includes determining metadata based on the sensor outputs of the multiple sensors. The metadata indicates one or more compensation operations for offsetting the beam offset in the image data. When the charged particle beam device is operated in an imaging mode, the image data is acquired by the charged particle beam device. The method also includes post-processing the image data based on the metadata and according to the one or more compensation operations.

[0032] The computer program or computer program product or computer readable storage medium comprises program code. The program code can be loaded and executed by at least one processor. The at least one processor is configured to perform this method of processing image data after loading and executing the program code.

[0033] This technique can reduce or fully compensate for disturbances in the post-processing of imaging data acquired by a charged particle beam device, for example when operating in imaging mode.

[0034] It is understood that the features mentioned above and those yet to be explained below can be used not only in the respective combination indicated but also in other combinations or alone, without departing from the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 Schematically illustrating placement offsets of a charged particle beam according to various examples.

[0036] Figure 2 Schematically illustrating various examples Figure 1 Compensation for placement offset.

[0037] Figure 3 Schematically illustrating various examples Figure 1 Compensation for placement offset.

[0038] Figure 4 Focus offsets and corresponding compensations of a charged particle beam according to various examples are schematically illustrated.

[0039] Figure 5 Focus shifts and corresponding compensations according to various examples are schematically illustrated.

[0040] Figure 6 A charged particle beam apparatus according to various examples is schematically illustrated.

[0041] Figure 7 is a flow chart of a method according to various examples.

[0042] Figure 8 is a flow chart of a method according to various examples.

[0043] Fig. 9 The time series data of sensor output and the characteristic finger-like ripples of the disturbance of the corresponding physical quantity according to various examples are schematically illustrated.

[0044] Fig.10 is a flow chart of a method according to various examples.

[0045] Fig.11 The implementation of a charged particle beam apparatus by a repair apparatus according to various examples is schematically illustrated.

[0046] Fig.12 Schematically illustrate various examples of Fig.11 Sensor placement of the prosthetic device.

[0047] Fig.13 Schematically illustrating various examples Fig.11 Sensor placement of the prosthetic device.

[0048] Fig.14 Defects of a photolithography mask according to various examples are schematically illustrated.

[0049] Fig.15 Repaired defects of a photolithography mask according to various examples are schematically illustrated.

[0050] Fig.16 A charged particle beam apparatus according to various examples is schematically illustrated. DETAILED DESCRIPTION

[0051] Some examples of the present invention generally provide multiple circuits or other electrical devices. All references to circuits and other electrical devices and the functions provided by each device are not intended to be limited to only cover what is illustrated and described herein. Although specific labels may be specified for various circuits or other electrical devices disclosed, such labels are not intended to limit the scope of operation of circuits and other electrical devices. Such circuits and other electrical devices can be combined and / or separated from each other in any manner based on the specific type of desired electrical implementation. It should be understood that any circuit or other electrical device disclosed herein may include any number of microcontrollers, graphics processor units (GPUs), integrated circuits, memory devices (e.g., flash memory, random access memory (RAM), read-only memory (ROM), electrically programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM) or other suitable variants thereof), and software that cooperates with each other to perform the operations disclosed herein. In addition, any one or more of the electrical devices may be configured to execute a program code specifically implemented in a non-transient computer-readable medium to perform any number of functions as disclosed.

[0052] The specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. It should be understood that the following description of the specific embodiments should not be considered as limiting. The scope of the present invention is not intended to be limited by the specific embodiments or drawings described below, which are only illustrative.

[0053] The drawings should be considered as schematic representations, and the elements illustrated in the drawings are not necessarily shown to scale. Instead, the various elements are represented so that the functions and general purposes thereof are apparent to those skilled in the art. Any connection or coupling between the functional blocks, devices, components or other entities or functional units shown in the drawings or described herein may also be implemented by indirect connection or coupling. Coupling between components may also be established by wireless connection. The functional blocks may be implemented by hardware, firmware, software or a combination thereof.

[0054] Below, the technology related to particle beam device is disclosed. In particular, the technology related to charged particle beam device is disclosed. The charged particles that such device can use are electrons and / or ions. In other examples, uncharged particles, such as photons, can be used. However, below, for illustrative purposes, multiple technologies will be disclosed in the context of charged particle beam device.

[0055] Examples of charged particle beam devices include: SEMs; aberration-corrected SEMs (typically with relatively large detector apertures and thus a small focal depth range); FIB devices; multi-SEMs; crossed-beam devices, including SEM and FIB optics; and SEMs or FIBs with precursor gas sources for repair / circuit editing tasks in manipulative mode (also referred to as repair devices; as will be described below in conjunction with Fig.11further detailed explanation).

[0056] The repair task involves modifying a structure on a semiconductor mask used for lithography. The repair task is implemented using an electron beam induced operation on the sample based on the interaction of one or more precursor gases with the electron beam. Alternatively or additionally, ions can be used for the repair or editing task. In some instances, the repair task is used to modify a semiconductor device, such as a circuit on a wafer. Specifically, charged particles - such as electrons or ions, such as helium or neon - are used to change the structure. For example, a charged particle beam interacts with one or more precursor gases selectively supplied to a sample stage. Then, one or more components of the one or more precursor gases are deposited onto the structure. In an example, a focused ion beam can also be used to remove material. The repair task is usually associated with a manipulation mode of a charged particle beam device that manipulates the sample / sample. Typically, the repair task includes using corresponding control signals to perform control of a beam source, a beam deflection unit, and a precursor gas source, thereby implementing electron beam induced manipulation of the sample. Examples of manipulation are: electron beam induced deposition (EBID) and electron beam induced etching (EBIE). This will be discussed later in conjunction with Fig.14 and Fig.15 An exemplary repair task is explained in more detail.

[0057] The various techniques disclosed herein are based on the discovery that as the typical size of structures being studied or modified (generally, structures characterized by a critical dimension that marks the minimum size of the structure that needs to be processed) continues to decrease, the requirements for accuracy in the operation of charged particle beam devices increase. For example, a typical critical dimension may be less than 7 nanometers or even less than 5 nanometers.

[0058]

[0013] Below, techniques are disclosed that facilitate operation of a charged particle beam apparatus in an inspection mode and / or a steering mode with high precision to enable processing of structures having small critical dimensions (eg, critical dimensions below 7 nanometers or even below 5 nanometers).

[0059] This is achieved by providing one or more compensation signals that compensate for the beam deviation. Details about this beam deviation and related compensation will be revealed in conjunction with the following figures.

[0060] Figure 1A charged particle beam 91 of a charged particle beam device is schematically shown, such as an electron beam or an ion beam, such as an ion beam of helium ions. The charged particle beam 91 is focused on a specific position 85 on a sample stage 113 of the charged particle beam device through an optical device of a beam deflection unit 112. However, due to one or more disturbances, a beam offset occurs, specifically a placement offset 81, which moves the charged particle beam 91 to another position 86 on the sample stage 113. This is a displacement along the x direction. Similarly, a displacement along the y direction is also possible. In addition, in addition to this placement offset 81, disturbances may also introduce other aberrations that cause reduced accuracy.

[0061] In general, the accuracy of charged particle beam devices depends on the resolution of the charged particle beam and the placement of the charged particle beam on the sample stage. The typical resolution is defined by the beam diameter, which is usually in the range of 3 to 5 nanometers or even lower (beam diameters below 1 nanometer for aberration-corrected instruments). On the other hand, the placement of the charged particle beam on the sample stage is usually affected by multiple perturbations of multiple physical quantities that affect the beam deviation, including the above combined Figure 1 Another type of beam offset is the focus offset, which will be discussed later in conjunction with Figure 4 and Figure 5 Explain it.

[0062] This placement offset that reduces beam placement accuracy is particularly important for the operation of charged particle beam devices, because the specification requirements imposed on the placement accuracy of the charged particle beam on the sample stage are often even higher than the specification requirements imposed on the beam diameter / resolution. One of the reasons for this is that, for example, in connection with the manipulation mode, certain structures need to be produced or edited with an accuracy of less than 3 nanometers, selectively less than 2 nanometers, or even less than 1 nanometer. In addition, although the placement offset when operating in the inspection mode may reduce the overall image quality of the acquired image, the placement offset caused by disturbances during manipulation may cause damage to expensive semiconductor structures or even photolithography masks.

[0063] Thus, techniques are disclosed that facilitate compensating for placement offset and focus offset by providing one or more compensation signals when a charged particle beam apparatus is operated in a steering mode.

[0064] According to various examples, the charged particle beam device includes a plurality of sensors for measuring a plurality of disturbances of a plurality of physical quantities. These plurality of physical quantities all affect the beam deviation of the beam on the sample stage. The charged particle beam device also includes a control unit, which is configured to determine one or more compensation signals based on the sensor outputs of the plurality of sensors to offset the beam deviation. The control unit is configured to provide the one or more compensation signals to at least one of the beam source of the charged particle beam device, the beam deflection unit of the charged particle beam device, the sample stage or one or more compensator modules.

[0065] Typically, beam offsets may include placement offsets (in Figure 1 in the X direction or Y direction, that is, along the plane of the sample stage 113) or the focus offset (in Figure 1 in the Z direction; perpendicular to the plane of the sample stage 113).

[0066] By taking into account disturbances originating from multiple physical quantities, a comprehensive compensation of the beam deviation is achieved. In particular, a more accurate compensation is achieved compared to the case where only individual physical quantities such as temperature, pressure, vibration or acoustic vibration (i.e. sound waves) are considered individually as known from the background art. The cross-correlations between different pairs of physical quantities can be taken into account, so that the compensation of the beam deviation is performed more accurately. For example, nonlinear effects due to the cross-correlations can be taken into account.

[0067] In general, various physical quantities are considered for compensation according to the examples. The plurality of physical quantities are selected from the group comprising: acoustic vibration, vibration, pressure, humidity, laminar airflow, turbulent airflow, differential quantity, temperature, rate of change (i.e. defining the rate of change over time), differential quantity, vector quantity (e.g. electric field, magnetic field) or scalar quantity (e.g. temperature, pressure).

[0068] The differential quantity describes the spatial gradient of the corresponding quantity, such as a temperature gradient or a pressure gradient. Typically, this differential quantity exerts stress or strain on the material, thus causing a disturbance. Further examples include laminar or turbulent airflow.

[0069] In some instances, acoustic vibrations include external acoustic vibrations, such as from objects moving around the charged particle beam device. Passive damping systems known in the prior art attempt to disconnect the charged particle beam device from its surroundings. However, this passive damping can not absorb all acoustic vibrations usually, so active compensation as described herein may be desirable. Acoustic vibrations may have a residual component of the movable parts in the charged particle beam device. These internal components can be excited by external acoustic vibrations via mechanical contact (such as via floor or support wire) or by sound.

[0070] In some instances, the pressure varies as a function of time. Pressure changes may occur over a relatively long time frame compared to, for example, acoustic vibrations. Passive compensation is known for pressure stabilization systems; however, this passive compensation has certain limitations in accuracy. The coolant or ambient air may experience pressure changes. Changes in ambient air pressure can change the forces applied to the vacuum housing of the charged particle beam device, resulting in changes in the hardware configuration.

[0071] According to some examples, temperature variation is compensated to some extent by passive temperature control, for example, using a stable temperature storage or an external air conditioning system. Use active control according to the technology disclosed herein can more accurately compensate for disturbances of even very small temperature variation. For example, according to various examples, a temperature sensor appropriately placed is used to measure the temperature variation of the cooling fluid. In further examples, the temperature of the cooling fluid is measured. In some other examples, the temperature variation of an electronic control device or a measuring device is measured and compensated. According to an example, the temperature difference / gradient between two or more parts of a charged particle beam device is measured. For example, the temperature gradient between different measuring points in a fluid stream (for example, a cooling fluid) is measured, and corresponding disturbances are compensated.

[0072] Another physical quantity that may cause disturbances is the electric field. Prior art systems usually use corresponding shielding. However, although this shielding may be effective to some extent for external electric fields, it may not be easy to shield internal electric fields, such as those generated by current or induced current or capacitor charging, using external shielding. Charged particle beams may cause unwanted particles in the column to be charged. On the other hand, using the technology described herein, in some instances, such as inside the vacuum chamber of a charged particle beam device, a sensor close to an optical device is used to measure the electric field, and then compensate for this electric field. Similar observations also apply to magnetic fields.

[0073] As can be seen from the above, some disturbances (such as magnetic fields or electric fields) have a direct impact on the charged particle beam by deflecting the charged particles propagating along the beam. For example, the electric field or magnetic field exerts a force on electrons or charged ions to deflect these particles. These are all direct disturbances. Disturbance can also have an indirect impact on the charged particle beam by affecting one or more parts of the charged particle beam device. For example, acoustic vibrations cause a positional offset of the optical device of the beam deflection unit of the charged particle beam device, and then this positional offset causes the beam offset of the beam. The electric field or magnetic field changes the analog supply current or voltage of the beam source or optical device of the beam deflection unit of the charged particle beam device; this then affects the placement offset. These are indirect disturbances. According to the technology disclosed herein, direct disturbances and indirect disturbances can be compensated.

[0074] For example, Figure 1 Placement offset as shown, or more generally, beam offset may occur in the imaging mode of a scanning electron microscope. Movement of magnetic materials such as iron, cobalt, nickel, steel, etc. may change the magnetic field where the charged particle beam is located. This may be caused by movement around the charged particle beam device, for example, due to elevators, cranes, doors, lift trucks, moving people, mobile phones, keys, etc.

[0075] Similar considerations apply to focused ion beam devices. Using a focused ion beam, material can be removed from a sample in a steered mode. If a disturbance affects the ion beam, material can be removed from unintended areas of the sample. Therefore, using the techniques disclosed herein, the ion beam is stabilized on the sample and the sample stage, respectively. This helps to avoid damaging the sample and achieve higher precision, for example in the preparation of transmission electron microscopy lamellae or in 3D tomography sample studies.

[0076] Similarly, for mask repair processing in manipulation tasks, structures on a lithography mask are repaired by depositing material using an electron beam or ion beam induced process; and / or material is locally removed from the lithography mask. By using the techniques disclosed herein, any beam offset of the electron beam or ion beam relative to the lithography mask and the sample stage, respectively, is reduced, allowing for greater accuracy in manipulation tasks.

[0077] In general, according to the disclosed examples, various options can be used to offset beam offset. According to the examples, different options for offsetting beam offset are adopted for different root causes of disturbances. For example, as described above, different options for offsetting beam offset are adopted for direct and indirect disturbances, respectively. For example, a compensation signal is applied to an optical device of a beam deflection unit to steer the beam to a direction opposite to the placement offset. For example, a compensation signal is applied to a focusing optical device of a beam deflection unit to change the focal length, thereby offsetting the focus offset caused by the corresponding disturbance. In some examples, alternatively or additionally, the sample stage is controlled to reposition to offset the beam offset. In yet further examples, special compensation is used for external coils such as applying a magnetic field or electric field plates for applying an electric field. For example, compensation of a DC magnetic field or a slowly changing magnetic field is implemented using a Helmholtz coil pair, with one coil pair for each spatial direction. This coil pair is positioned outside the housing of the charged particle beam device. According to further examples, active cooling or heating is used. For example, a heating or cooling element in thermal contact with a coolant is provided, and active temperature control can be performed. In some examples, active damping for suppressing vibrations is controlled. In some examples, the pressure is actively controlled. Hereinafter, a device or unit that indirectly compensates for beam deviation (i.e., does not directly apply a force to the charged particle beam by applying a magnetic field or an electric field, or does not move the sample stage relative to the charged particle beam) is referred to as a compensator module. This compensator module is controlled by a respective compensation signal.

[0078] In the following, the technique is mainly explained in connection with applying a compensation signal to the beam deflection unit and / or the sample stage. Next some example options for counteracting beam deviations in this way are explained.

[0079] Figure 2 Example about offset Figure 1 Place the offset 81 in the Figure 2As shown, an additional beam shift 82 that offsets the placement shift 81 is achieved by providing a control signal to the beam deflection unit 112. For example, an additional voltage is applied to the corresponding electron lens.

[0080] Figure 3 Schematic illustration of offset Figure 1 The placement offset is 81. Figure 3 In this case, a compensation signal is applied to the control motor of the sample stage 113 to achieve a stage shift 83 that offsets the placement offset 81.

[0081] like Figure 3 Techniques of the type shown may be particularly helpful for closed-loop control of the motorized stage 113. For example, interferometric stages are known that achieve nanometer-level positioning accuracy.

[0082] Above, a placement offset scenario affected by multiple perturbations has been disclosed. Alternatively or additionally to affecting the placement offset, the perturbations may affect the focus offset of the charged particle beam. Figure 4 In the description.

[0083] exist Figure 4 In FIG. 1 , an unaffected beam 91 is illustrated without any disturbance. Furthermore, two disturbed beams 93, 94 are illustrated which are subjected to respective focus shifts 71, 72. The focus shifts 71, 72 can be counteracted by applying additional defocusing to the beams. In this way, the beam deflection unit 112 can be controlled accordingly. Here, a defocus 75 is illustrated for counteracting the focus shift 71, and a defocus 76 is illustrated for counteracting the focus shift 72. In an alternative, as Figure 5 As shown, corresponding vertical stage shifts 77, 78 may also be applied.

[0084] According to various embodiments, the compensation of focus shift is applied to an aberration-corrected SEM. Typically, an aberration-corrected SEM has a relatively large numerical aperture and thus a shallow depth of focus range. Such an aberration-corrected SEM may be used for manipulation tasks, and the thickness of the structure to be manipulated may be the same as or even smaller than the depth of focus range. In this case, the compensation of focus shift is particularly important to obtain good manipulation task results.

[0085] Various techniques are based on the discovery that disturbances can occur on different time scales. On the one hand, there may be slowly varying disturbances caused by, for example, DC magnetic fields, temperature or pressure changes, etc. In general, the techniques disclosed herein can be used to compensate for such slowly varying disturbances, for example by applying one or more compensation signals to counteract beam deviations. Here, compensation is performed by applying an additional voltage to the beam optics (see Figure 2 or Figure 4 ), which typically provides a shorter response time than compensation based on stage displacement, see Figure 3 and Figure 5This is because the movement of the stage usually requires a longer duration due to the limited movement speed of the motor. The operation of the charged particle beam device, such as imaging mode or manipulation mode, does not have to be stopped for this compensation, and the compensation can be applied during ongoing operation.

[0086] On the other hand, some disturbances may vary on a fast time scale, for example within a few seconds or even within a sub-second range. Examples relate to physical quantities, such as acoustic or seismic vibrations, for example vibrations due to vibrations of building foundations. In order to also compensate for this fast disturbance, the following will disclose a technology capable of determining a predicted component of a beam offset. Alternatively or additionally, information about this disturbance is stored in a further example, and this information is determined based on a sensor output (for example, together with imaging data collected in an imaging mode). In other words, according to an example, based on the sensor outputs of a plurality of sensors, metadata indicating one or more compensation operations is determined to offset the beam offset in the image data collected by a charged particle beam device operating in an imaging mode, and then the metadata is stored in association with the image data. Then, the collected image data is digitally post-processed to compensate for such disturbances based on the metadata after collection.

[0087] In some instances, a disturbance is detected that causes the charged particle beam device to suspend operation, for example, the charged particle beam may be blanked. Imaging mode or manipulation mode is interrupted until the disturbance is resolved. This is particularly helpful in manipulation mode to avoid damage to the manipulated sample.

[0088] Figure 6 The charged particle beam device 100 according to various examples is schematically illustrated. For example, the charged particle beam device 100 may be a charged particle beam repair device. The charged particle beam device 100 includes a vacuum chamber 110. A beam source 111, a beam deflection unit 112, and a sample stage 113 are arranged in the vacuum chamber 110. An embedded control unit 119 controls the beam source 111, the beam deflection unit 112, and the sample stage 113. The control unit 119 may also control other components of the charged particle beam device 100, such as a control valve ( Figure 6 not shown).

[0089] Two sensors 121 and 122 for measuring disturbances of physical quantities are also illustrated, each of which affects the beam deviation of the charged particle beam 90 on the sample stage 113 .

[0090] Although in Figure 6 In the scenario of FIG. 2 , two sensors 121 and 122 are illustrated, but typically, only a single sensor may be used or more than two sensors may be used.

[0091] In some examples, at least one of the plurality of sensors is disposed inside the vacuum chamber 110. Alternatively or additionally, at least one sensor is disposed outside the vacuum chamber 110.

[0092] For example, sensors measuring the same physical quantity (e.g. temperature) are located at multiple locations. Thus, differential physical quantities such as temperature or pressure differences are measured.

[0093] By placing the sensor outside the vacuum chamber, physical quantities that vary slowly as a function of position, such as external electric fields or external magnetic fields, can be measured. At the same time, the influence of the particle beam by operating the sensor can be avoided. In some examples, the sensor is still placed closer to the beam path of the beam 90, for example, for physical quantities that exhibit strong position dependence.

[0094] A control unit 130 is also illustrated. In some examples, the control unit 130 is implemented by a computer. The control unit 130 communicates with the embedded control unit 119 and the sensors 121, 122. Figure 6 2 illustrates a scenario in which the control unit 130 communicates directly with the sensors 121 , 122 , but in other examples this communication takes place via the embedded control unit 119 .

[0095] In any case, the control unit 130 obtains sensor signals 161, 162 (ie, sensor outputs) from the sensors 121, 122. Based thereon, the control unit 130 provides one or more compensation signals 165 to one or more components of the charged particle beam apparatus 100 to counteract the placement offset.

[0096] The control unit 130 includes a processor 132 coupled to a memory 133. The processor 132 also communicates via a communication interface 131. The processor loads program code from the memory 133 and executes the program code. When executing the program code, the processor 132 performs the techniques disclosed herein for compensating for multiple perturbations of multiple physical quantities that each affect beam deviation.

[0097] The control unit 130 also includes a human machine interface (HMI) 134, such as a display, a web interface, a mouse, a keyboard, etc. User input is received via the HMI 134 or information is output via the HMI 134. For example, an indication of a disturbance event at a specific location is obtained from the user via the HMI 134. In some examples, a warning is output to the user via the HMI 134.

[0098] Although the following discloses the context of associated logic for beam offset compensation residing at the control unit 130 , in other examples, at least a portion of this logic resides at the embedded control unit 119 .

[0099] Figure 7is a flow chart of a method according to various examples. Figure 7 Examples include Figure 6 The charged particle beam device 100 is a multiple stage of operation of the charged particle beam device. Figure 7 The method may be executed by the control unit 130 and / or the embedded control unit 119 .

[0100] Block 6005 corresponds to a calibration phase. During the calibration phase, one or more transfer functions are established between the sensor outputs of a plurality of sensors measuring a plurality of physical quantities and the disturbance of the compensation signal.

[0101] Thus, this transfer function links the values ​​of a plurality of physical quantities (represented by the sensor signals 161 , 162 ) to the beam deviation compensation (represented by the compensation signal 165 ).

[0102] Box 6010 corresponds to an operation phase. During the operation phase, the charged particle beam device operates in an imaging mode or a manipulation mode. For example, as part of the imaging mode, the control unit of the charged particle beam device may provide control signals to a beam source and a beam deflection unit of the charged particle beam device to implement imaging of a sample mounted on a sample stage of the charged particle beam device. As part of the manipulation mode, the control unit of the charged particle beam device provides control signals to the beam source, the beam deflection unit, and a precursor gas source (e.g., including a gas tank or a gas storage tank and a corresponding nozzle located near the sample stage; details will be described in conjunction with Fig.11 A) to implement electron beam induced manipulation of a sample mounted to a sample stage. Herein, a precursor gas supplied by a precursor gas source interacts with electrons of the electron beam. Materials can be deposited or locally etched.

[0103] In the operation phase, compensation of multiple disturbances of multiple physical quantities is adopted; each of the multiple physical quantities affects the beam deviation of the charged particle beam device relative to the sample stage. For example, the control unit uses the transfer function obtained from block 6005 to determine one or more compensation signals to offset any beam deviation based on the sensor outputs of the multiple sensors, and then provides the one or more compensation signals to one or more parts of the charged particle beam device.

[0104] Figure 7Also illustrated in the figure is an optional post-processing stage associated with box 6015. Herein, metadata obtained based on sensor outputs of multiple sensors is used to apply one or more compensation operations to offset beam offsets by post-processing corresponding image data. In some instances, such compensation operations include applying imaging shifts, for example, shifting pixels of an image included in the image data by a specific image offset. In addition, rotation operations or skew operations are used in further instances. In some instances, complex image artifacts are compensated. Examples of image artifacts include artificially repetitive contrast. To compensate for this, a neural network that obtains configuration information in the form of metadata can be used to implement the compensation operations.

[0105] like Figure 7 As shown in the dashed line, the calibration mode of block 6005 can be re-executed at any time. Thus, certain disturbance events that are site-specific, ie, depend on a specific deployment side of the charged particle beam device, are captured. This will be explained in more detail later.

[0106] Next, combine Figure 8 Details regarding the calibration phase of block 6005 are disclosed.

[0107] Figure 8 is a flow chart of a method according to various examples. Figure 8 Details regarding the calibration phase of block 6005 are illustrated.

[0108] Initially, at block 6105, one or more perturbations are applied; this is accomplished by modifying one or more physical quantities. Some examples are: applying some perturbing electric or magnetic field (e.g., using a Helmholtz coil around a charged particle beam device), changing the surrounding temperature (e.g., in a temperature-stable environment), changing the surrounding pressure, etc. When one or more perturbations are actively applied, the corresponding amplitude of the perturbation is known.

[0109] It will be apparent from the above that for calibration purposes a "tailored" disturbance event is therefore triggered.

[0110] Typically, this active application of some disturbance is optional. In other scenarios, at block 6110, naturally occurring disturbances, such as site-specific disturbances, are measured. In other words, in some scenarios, disturbance events are actively triggered at block 6105; while in other scenarios, environmental disturbance events are monitored and characterized at block 6110.

[0111] Then, at block 6115, the beam offset may be measured.

[0112] This beam offset can be produced by a corresponding customized disturbance actively applied at box 6105; alternatively, the beam offset can be caused by a naturally occurring disturbance (e.g., by an environmental disturbance event). For example, a placement offset and / or a focus offset of the beam is measured. This can be achieved using, for example, a test pattern sample and using a corresponding inspection task. For example, an image of the test pattern obtained by a charged particle device operating in an imaging mode in the presence of a disturbance is compared with ground truth knowledge about the test pattern. From the deviation between the image appearance of the test pattern and the ground truth about the test pattern, conclusions about the beam offset are drawn. For example, an image shift between the actual position of certain features of the test pattern and the position where these features are depicted in the image can be determined. For example, image blur can be quantified to determine the focus offset.

[0113] Then, at block 6120, a transfer function between the disturbance and the beam offset is determined. This transfer function is then stored for later use during the compensation mode (see Figure 7 :Box 6010).

[0114] Next, various examples of determining the transfer function at block 6120 will be discussed.

[0115] In one example, one or more compensation signals are determined using a lookup table linking the sensor output with the one or more compensation signals. In other words, for a plurality of disturbance intensities, such as a plurality of values ​​of a respective physical quantity, the associated beam offset and thus the compensation signal required for compensation are determined. The corresponding value pairs are then stored in the lookup table. Linear interpolation may be optionally used during operation to improve accuracy.

[0116] The lookup table can be device-specific, i.e. different charged particle beam devices can have different lookup tables. Site-specific perturbations can be used to populate such device-specific lookup tables. The lookup table can also be stored in the cloud so that it can be retrieved over the network. This allows centralized maintenance and management of perturbation compensation for multiple charged particle beam devices.

[0117] Table 1 below provides an exemplary lookup table:

[0118] Temperature disturbance Offset Voltage +0.2K +0.3V +0.4K +0.58V +0.6K +0.88V

[0119] Table 1 : Exemplary lookup table linking temperature perturbations in the offset voltage to be applied at the beam optics of a beam deflection unit of a charged particle apparatus.

[0120] The advantage of this lookup table is that it does not require the use of a predetermined function to model the dependency between the sensor output and the compensation signal. Nonlinear dependencies are captured directly. On the other hand, this lookup table may have a large size. This may result in a delay in finding the appropriate compensation signal, which may be a problem, especially for rapidly changing disturbances.

[0121] In another example, one or more compensation signals are determined using a (pre-parameterized) functional dependency. This functional dependency is illustrated for the linear case.

[0122] For example, for a scalar physical quantity such as temperature, this linear functional dependence can be defined as follows:

[0123]

[0124] Herein, ΔT represents a temperature disturbance (eg, defined with respect to a reference temperature) and is obtained from the sensor output, P x represents the x component of the placement offset compensation, P y represents the y component of the placement offset compensation, and P z represents the compensation of the focus shift. Then, the linear function dependence is given by the parameter These are determined during calibration (pre-parameterization). Placement offset defines one or more compensation signals.

[0125] For example, for a vector quantity (such as the electric field), this linear functional dependence can be defined as follows:

[0126]

[0127] Where E c is a 3x3 matrix, where the matrix elements are determined during calibration. x ,ΔE y ,ΔE z represents the component of the perturbed electric field. In the above scenario, known physical quantities (such as temperature, electric field, etc.) will affect the beam deviation. The effects of different physical quantities on the beam deviation can be superimposed. In some scenarios, different physical quantities can be considered independent of each other, that is, the mixing effect between the effects of different physical quantities on the beam deviation is ignored.

[0128] In some cases, it is necessary to consider the mutual dependencies between multiple disturbances associated with different physical quantities.

[0129] For example, one example is the mutual dependence between temperature and pressure as follows:

[0130]

[0131] where the 2x3 matrix X c has non-zero off-diagonal elements that define the mutual dependence between the pressure and temperature perturbations.

[0132] In the above, linear functional dependencies have been disclosed, but nonlinear terms such as quadratic terms, cubic terms, etc. may also be included.

[0133] In addition to this functional dependency illustrated above, in another example, a model is used to determine one or more compensation signals. For example, a trained neural network or another machine learning algorithm or typically a pre-trained algorithm is used to determine compensation for positioning and focus offsets. The trained neural network receives as input a vector that includes sensor outputs of multiple sensors, such as temperature, pressure, multiple components of an electric field, multiple components of a magnetic field, etc. The neural network then outputs one or more compensation signals, or outputs a beam offset from which one or more compensation signals are determined. This neural network is trained using ground truth labels obtained during the calibration mode, i.e., the beam offset measured at block 6115 is combined with the input vector determined at block 6105 or block 6110.

[0134] This is an example of a data driven model. In other examples, an analytical model may also be used. For example, changes in pressure have been shown to cause a twisting of the beam optical column. This causes the focus to be displaced on a circle that is tilted relative to the sample stage surface, i.e. the displacement has x, y and z components. Focus shifts in the +z direction or in the -z direction may occur. According to the example, an analytical model is determined, which determines the torque applied to the optical column based on the pressure gradient. For example, the advantage of this analytical model is a reduced lead time in the parameterization compared to a lengthy calibration of the transfer function. In some examples, this model can be extended to also cover placement shifts based on other perturbations (such as magnetic fields).

[0135] Above, the context of instantaneous compensation of disturbances has been disclosed. Such techniques are generally well suited for slowly varying disturbances, such as disturbances in the kHz or lower frequency band. For rapidly varying disturbances, even higher accuracy can be achieved by taking into account the time-resolved nature of the disturbance. This is explained further below.

[0136] According to various examples, a predicted component of the beam offset is determined based on sensor outputs of a plurality of sensors, and one or more compensation signals are determined based on the predicted component of the beam offset. In other words, a disturbance is expected to occur within a certain look-ahead period.

[0137] Such techniques are based on the discovery that certain disturbance events are repetitive. Specifically, location-specific disturbance events may reoccur over time. For example, a stray magnetic field may be caused by the movement of an office chair between two tables in a laboratory or in a deployment site for a charged particle beam device. For example, vibrations may be caused by trains entering and exiting a nearby train station, or delivery trucks arriving or leaving a loading dock. In another example, a stray magnetic field may be caused by equipment operation in a wafer fab, such as the opening or closing of a load lock, the decompression of a vacuum chamber, or temperature changes as a function of daytime / sun altitude. These are just some examples of typical, location-specific, repetitive disturbance events.

[0138] To make this prediction, in some instances, the sensor output of at least one of the plurality of sensors includes corresponding time series data. In other words, sensor readings within a particular observation duration are considered (e.g., along with corresponding timestamps). A prediction component is then determined based on an analysis of the time series data.

[0139] There are a number of options for performing such time series data analysis. In one option, one or more finger-like ripples of a predetermined disturbance event are found in the time series data, the finger-like ripples comprising characteristic time dependencies of the sensor output of the corresponding at least one sensor. The finger-like ripples are characteristic time domain patterns, which are Fig. 9 In the description.

[0140] Fig. 9 An illustrative example is taken to illustrate a disturbance of the x-component of the electric field affecting the beam deflection of a charged particle beam over time.Time series data 310 of the x-component of the electric field is obtained from a corresponding electric field sensor.

[0141] For example, a disturbance event 311 is illustrated, which is caused by a bus arriving at a bus stop near the deployment site of the charged particle beam device. The corresponding disturbance duration 313 is also illustrated here. For example, the disturbance duration 313 can be in the range of seconds or minutes.

[0142] The disturbance event 311 has a characteristic finger-like ripple 312 (herein: a large rise followed by a small drop) detected in the time series data of the electric field sensor. Once this finger-like ripple 312 is found, a prediction of the future behavior of the disturbance can be made, i.e. a predicted component of the beam deviation can be determined (under the assumption of the repetitive nature of the disturbance). The behavior of the disturbance during the remaining disturbance duration 313 can be predicted.

[0143] When operating in the calibration phase of block 6005 (see Figure 7 ), according to some examples, the repository is filled with finger ripples of multiple disturbance events. In order to find this finger ripple, a variety of options are conceivable. In one option, the repetition of the finger ripple is identified. For example, during a calibration mode, the sensor output of the corresponding at least one sensor is monitored for an extended duration (e.g., hours or days or even weeks), and then the repetition of the finger ripple is found. In a further option, user input data indicating a corresponding one of the one or more disturbance events is obtained. For example, referring to Fig. 9, the user labels / annotates the time series data to identify the disturbance duration 313. The user may do so using domain knowledge, e.g., in the example discussed, the user may know that a bus arrives at a bus stop. Another option includes training a prediction model based on the time series data measured during the calibration mode to find fingering. The prediction model (e.g., a recurrent neural network such as a long short-term memory (LSTM) neural network) is then enabled to determine the predicted component of the beam offset. This enables reaction to disturbance events with high bandwidth signal components. In other words, disturbance events with fast temporal dynamics, such as sub-millisecond or even microsecond disturbance events, can be compensated. This is because once fingering is detected, a compensation signal can be actively sent out.

[0144] Fig.10 A flow chart of an exemplary method is shown. Fig.10 Schematic display Figure 7 Operations in the operation phase of box 6010.

[0145] At block 6205, a plurality of sensors of a charged particle beam device measure a plurality of disturbances of a plurality of physical quantities, each physical quantity affecting a beam offset of a charged particle beam on a sample stage, such as a placement offset and / or a focus offset. A corresponding sensor output comprising a plurality of sensor signals provided by the plurality of sensors is provided herein. The sensor output indicates a value of the physical quantity. That is, the sensor output is associated with the disturbance. These disturbances may be superimposed or interrelated.

[0146] In general, different placements of multiple sensors are conceivable. Exemplary placements will be discussed later. Fig.12 and Fig.13 Have a discussion.

[0147] Next, at block 6210, one or more compensation signals are determined to counteract this beam shift. This is based on the sensor outputs of the plurality of sensors. More specifically, disturbances are estimated from the sensor outputs and converted into one or more compensation signals.

[0148] The examples above have revealed aids in determining such compensation signals, such as using a transfer function that may be implemented via a lookup table, a model (e.g., a data driven model using machine learning or an analytical model), functional dependencies, a machine learning algorithm, and the like.

[0149] A predicted component of the beam offset may also be determined, thereby reducing delay and applying a compensation signal and providing more accurate compensation.

[0150] In some cases, instead of or in addition to determining a compensation signal to actively compensate for beam drift during operation of the charged particle beam device (e.g., in an imaging mode or a steering mode), metadata indicating one or more compensation operations is determined to counteract beam drift in the imaging data. This enables post-processing of the imaging data (see Figure 7 : Block 6015). Herein, compensation for beam deviation is achieved when digital post-processing imaging data acquired using a charged particle beam apparatus; alternatively or additionally, at least a portion of the beam deviation is compensated during operation.

[0151] A degree of confidence in the corresponding image data may be determined. A log file may be generated to store the disturbance or specifically to store one or more compensation signals.

[0152] At block 6211, the operating accuracy of the charged particle beam device during the prediction duration may be predicted based on the sensor output and / or one or more compensation signals determined at block 6210. This may be equivalent to predicting the degree of disturbance. For example, a recurrent neural network or LSTM is used to make such predictions. Furthermore, this prediction may be based on characteristic finger-like ripples of repeated disturbance events, such as in combination with Fig. 9 Discussed. Different from combining Fig. 9 As explained, a prediction of this level of accuracy may not directly affect the compensation signal. Sometimes, the prediction may not be accurate enough to determine the predicted component of one or more compensation signals. In this case, the accuracy may also be predicted. In some examples, this accuracy is output to the user via the HMI. The user can then decide whether to abort the operation. In other examples, the prediction of the accuracy is used in the context of block 6215.

[0153] Sometimes, a disturbance occurs that exceeds or is expected to exceed (see block 6211) a predetermined critical value. If the disturbance exceeds the predetermined threshold, it is considered that the disturbance cannot be compensated.

[0154] Thus, at block 6215, a check is made as to whether one or more predetermined events are detected in the sensor outputs of the plurality of sensors. In some instances, the one or more predetermined events are associated with at least one of the plurality of disturbances exceeding a predetermined threshold; this corresponds to the sensor output exceeding a relative threshold. In a further instance, a check is made as to whether one or more compensation signals exceed a particular threshold. An alternative instance of the one or more predetermined events is detecting anomalies in the sensor outputs. In some instances, an anomaly detector algorithm is used: examples include clustered anomaly detection or autoencoder neural networks. The anomaly detector algorithm may be trained in an unsupervised manner.

[0155] If one or more predetermined events are not detected at block 6215, block 6205 is re-executed, i.e., the disturbance is measured again and the compensation signal is further applied. On the other hand, if excessive disturbance is detected at block 6215, the beam is blanked at block 6220. For example, the inspection or manipulation mode is aborted. Alternatively or additionally, a warning message is output via the HMI. In some examples, the corresponding sensor output that caused the execution of block 6220 is recorded. According to some examples, a safe mode is entered that can be manually exited by the user.

[0156] Beam blanking may be performed at a relatively low latency to avoid corruption. For example, determining one or more compensation signals may typically require a significant amount of time, such as performing a lookup operation or calculating the compensation signals. Therefore, in some examples, beam blanking may be performed at a lower latency than determining one or more compensation signals.

[0157] Typically, according to some examples, the decision flag at block 6215 is based on sensor signals other than the sensor signals considered by the logic at block 6210. For example, the following physical quantities have been found to be particularly suitable for detecting excessive disturbances at block 6215: acoustic vibrations, vibrations, ambient pressure, ambient pressure changes. On the other hand, the following physical quantities have been found to be particularly suitable for determining one or more compensation signals to counteract beam deviations: magnetic field, ambient temperature, ambient pressure, ambient pressure changes.

[0158] Fig.11 An exemplary embodiment of a charged particle beam device such as the charged particle beam device 100 described above is schematically illustrated. Fig.11 The scenario involves a charged particle beam repair device (or simply a repair device). Fig.11 A schematic cross-sectional view showing some important components of one example of a repair apparatus 11120 that can be used to identify and repair defects 11160 of a photolithography mask. A sample 11405 can be arranged on a sample stage 11402 (corresponding to sample stage 113), for example, in the form of a photolithography mask 11110. The photomask can have one or more defects 11160 in the form of excess material ("dark defects") and / or missing material ("bright defects"). Fig.11Defects of the photolithography mask are not reproduced in the repair device 11120. Defects of excess or missing material or general defects can be scanned and analyzed with the help of a charged particle beam. In addition, defects can be corrected by particle beam induced processing. For this purpose, the repair device 11120 includes a scanning electron microscope (SEM) 11410. In addition, defects of excess material can be repaired by the measuring tip of a scanning probe microscope 11480. Therefore, the repair device 11120 includes one or more scanning probe microscopes 11480, which are usually in the form of atomic force microscopes (AFM) 11480.

[0159] exist Fig.11 In the SEM 11410, an electron gun implementing a beam source 11412 generates an electron beam 11415, wherein an imaging element (implementing a beam deflection unit) is configured in an electron column 11417, and the imaging element is not Fig.11 , the electron beam is directed / deflected as a focused electron beam 11415 onto a sample 11405 at position 11422, which (as explained) may include a photolithography mask. The sample 11405 is disposed on a sample stage 11402. The sample stage 11402 is also referred to in the art as a "stage". Fig.11 As shown by the arrows, the positioning unit 11407 can move the sample stage 11402 around six axes relative to the column 11417 of the SEM 11410. The positioning unit 11407 can move the sample stage 11402 with the aid of, for example, Fig.11 This is accomplished using a micromanipulator not shown.

[0160] At the processing position 11422, the particle beam 11415 impacts the sample 11405. Therefore, the positioning unit 11407, by means of the displacement of the sample stage 11402 perpendicular to the beam axis of the electron beam 11415, makes it possible to analyze the defects of the mask (inspection task) first by generating an image of the defects. For this purpose, the imaging element of the column 11417 of the SEM 11410 can scan the electron beam 11415 on the sample 11405. By tilting and / or rotating the sample stage 11402 along the sixth axis, it makes it possible to inspect one or more defects from different angles or viewing angles. The corresponding positions of the various axes of the sample stage 11402 can be measured by interferometry ( Fig.11 The positioning unit 11407 is controlled by a signal from the control unit 11425. The control unit 11425 may be part of the computer system 11430 of the repair device 11120. In some examples, the control unit 11425 implements the control unit 119 or the control unit 130 (see Figure 6 ).

[0161] The repair device 11120 may further include one or more sensors that enable characterization of the current state of the SEM 410 and the processing environment (e.g., vacuum environment) in which the SEM 11410 is used. For example, vibration, temperature, pressure, their respective differences or rates of change (over time) may be measured.

[0162] Furthermore, the electron beam 11415 can also be used to induce a particle beam induced process for correcting the identified defects, such as in the context of an electron beam induced etching process EBIE (electron beam induced etching) for removing dark defects, and / or in the context of an electron beam induced deposition process EBID (electron beam induced deposition) for correcting bright defects. Fig.11 In the repair device 11120, the electron beam 11415 can be used to analyze the repair position of the photomask.

[0163] Electrons backscattered from the electron beam 11415 by the sample 11405 and secondary electrons generated by the electron beam 11415 within the sample 11405 are recorded by a detector 11420. If the sample 11405 includes a photomask, the detector 11420 identifies secondary electrons emitted during scanning of absorption strips disposed on the mask for photolithography purposes. A detector 11420 disposed in the electron column 11417 is referred to as an "in lens detector". In various embodiments, the detector 11420 may be mounted in the column 11417. The detector 11420 may also be used to detect electrons backscattered from one or more defects 11160 of the mask 11110. The detector 11420 is controlled by a control unit 11425 of a computer system 11430 of the device 120. For example, the computer system 11430 may implement the control unit 130. The embedded control unit 119 may be implemented by the control unit 11425.

[0164] The repair device 11120 may include a second detector 11445. The second detector 11445 is designed to detect electromagnetic radiation, in particular in the X-ray range. Thus, the second detector 11445 enables the material composition of the sample to be analyzed, such as a photolithography mask (i.e., its substrate), an absorbing strip and / or one or more defects. The detector 11445 is likewise controlled by the control unit 11425.

[0165] A control unit 11425 of the computer system 430 (which may also be separate from the computer system 430) may set parameters of the electron beam 11415 to induce a deposition process for removing bright defects and / or an EBIE process for etching dark defects.

[0166] Furthermore, the computer system 11430 has an evaluation unit 11435. The evaluation unit 11435 receives the measurement data of the detectors 11420, 11445. The evaluation unit 11435 can generate an image in grayscale representation or grayscale value representation on the monitor 11432 from the measurement data, for example based on the secondary electron contrast data. In addition, the computer system 11430 includes an interface 11437, via which the computer system 11430 can transmit to another processing device. In addition, the computer system 11430 of the repair device 11120 can receive one or more processed or evaluated images and / or one or more superimposed images from the evaluation device.

[0167] As explained above, the electron beam 11415 of the modified SEM 11410 can be used to induce electron beam induced processing / manipulation. Also as explained above, defects in the sample 11405 can be corrected by electron beam induced manipulation. In order to perform these processes, Fig.11 An exemplary scanning electron microscope 11410 of the repair device 11120 has three different supply containers 11450 , 11460 , and 11470 .

[0168] The first supply container 11450 stores a first precursor gas in the form of a deposition gas, for example a metal carbonyl, such as chromium hexacarbonyl (Cr(CO)6), or a carbon-containing precursor gas, such as pyrene. With the aid of the precursor gas stored in the first supply container 11450, a material can be deposited on the sample 11405 or the mask in a local chemical reaction, wherein the electron beam 11415 of the SEM 11410 acts as an energy supplier to separate the precursor gas stored in the first supply container 11450 into chromium atoms and carbon monoxide molecules, preferably at the location where the material is intended to be deposited (i.e., at the location of the bright defect). This means that an EBID process for correcting photomask defects is performed by providing the electron beam 11415 and the precursor gas in combination. The modified SEM 11410 forms a repair device 11120 in combination with the first supply container 11450 or the deposition gas stored therein.

[0169] exist Fig.11In the illustrated repair device 11120, the second supply container 11460 stores a precursor gas in the form of an etching gas, which allows a local electron beam induced etching (EBIE) process to be performed. Here, defects or dark defects of excess material can be removed from the photolithography mask 11110 (or another sample, such as a semiconductor wafer) by means of an electron beam induced etching process. The precursor gas in the form of an etching gas may include, for example, xenon difluoride (XeF2), chlorine (Cl2), oxygen (O2), ozone (O3), water vapor (H2O), hydrogen peroxide (H2O2), nitrous oxide (N2O), nitric oxide (NO), nitrogen dioxide (NO2), nitric acid (HNO3), ammonia (NH3) or sulfur hexafluoride (SF6) or a combination thereof. Therefore, the modified SEM 11410 is combined with the second supply container 11460 or the precursor gas stored therein to form the repair device 11120.

[0170] The additive gas may be stored in the third supply container 11470, which additive gas can be added, when necessary, to the etching gas remaining available in the second supply container 11460, or to the deposition gas stored in the first supply container 11450. Alternatively, the third supply container 11470 may store a precursor gas in the form of a second etching gas or a second deposition gas.

[0171] exist Fig.11 In the illustrated scanning electron microscope 11410, each supply container 11450, 11460 and 11470 has its own control valve 11452, 11462 and 11472 to monitor or control the corresponding gas amount supplied per unit time, that is, the gas volume flow rate at the incident position 11422 of the electron beam 11415 on the sample 11405. The control valves 11452, 11462 and 11472 are controlled and monitored by the control unit 11425. By this device, the partial pressure conditions of one or more gases supplied at the processing position 11422 can be set to adjust the partial pressure of the gas during operation (see Figure 7 : Box 6010) performs EBID and / or EBIE processing within a wide range.

[0172] In addition, Fig.11 In the exemplary SEM 11410, each supply container 11450, 11460 and 11470 has its own gas feed line system 11454, 11464 and 11474, which ends at a nozzle 11456, 11466 and 11476 located near the incident point of the electron beam 11415 on the sample 11405 (i.e., the processing position 11422).

[0173] The supply containers 11450, 11460 and 11470 may have their own temperature setting elements and / or control elements, which allow cooling and heating of the corresponding supply containers 11450, 11460 and 11470. This makes it possible to store and in particular provide the precursor gases of the deposition gas and / or etching gas at the respective optimal temperature ( Fig.11 1440 and 11470. The control unit 11425 may control the temperature setting elements and the temperature control elements of the supply containers 11450, 11460, and 11470. During the EBID and EBIE processes, the temperature setting elements of the supply containers 11450, 11460, and 11470 may further be used to set the vapor pressure of the process gas stored therein by selecting an appropriate temperature.

[0174] The apparatus 11400 may include more than one supply container 740 to store two or more precursor gases of deposition gases. Furthermore, the apparatus 400 may include more than one supply container 11460 to store two or more precursor gases of etching gases.

[0175] Fig.11 The scanning electron microscope 11410 illustrated in the figure can be operated under ambient conditions or in a vacuum chamber 11442. A negative pressure relative to the ambient pressure in the vacuum chamber 11442 is required to implement EBID and EBIE processing. For this purpose, Fig.11 The SEM 11410 in the embodiment includes a pump system 11444 for generating and maintaining the required negative pressure in the vacuum chamber 11442. By closing the control valves 11452, 11462 and 11472, a vacuum pressure of <10 -4 The residual gas pressure of Pa. The pump system 11444 may include a separate pump system ( Fig.11 11442) for the upper half of the vacuum chamber 11442, for providing the electron beam 11415 of the SEM 11410; and for the lower half or reaction chamber 11448. A pressure sensor may be provided to monitor the pressure inside and outside the vacuum chamber 11442. In this way, the pressure difference can be monitored.

[0176] Fig.11 The SEM 11410 presented in the repair device 11120 in FIG. 1 has a single electron beam 11415. However, the SEM 11410 may also have a second particle beam source. The second particle beam may include a photon beam and / or an ion beam ( Fig.11 Furthermore, the SEM 11410 may have two or more electron beams 11415 to be able to perform two or more particle beam induced treatment processes, or two or more analysis processes of two or more defects in parallel.

[0177] Additionally, Fig.11The exemplary repair device 11120 illustrated in FIG. 1 includes a scanning probe microscope 11480, which is implemented in the repair device 11120 in the form of a scanning force microscope (SFM) 11480 or an atomic force microscope (AFM) 11480. The scanning probe microscope 11480 can be used to scan one or more defects 11160 of the sample 11405 or the photomask 11110. Furthermore, the scanning probe microscope 11480 can be used to repair defects of excess material. For this purpose, the scanning probe microscope 11480 can include a first measurement tip for analyzing the sample 11405, and a second measurement tip for processing the one or more defects.

[0178] Only the measuring head 11485 of the scanning probe microscope 11480 is Fig.11 The repair device 11120 is shown. Fig.11 In the example of, the measuring head 11485 includes a holding device 11487. The measuring head 11485 is provided with the holding device 11487 ( Fig.11 The piezoelectric actuator 11490 is fixed to the frame of the repair device 11120 (not shown). The free end of the piezoelectric actuator 11490 can move in three spatial directions ( Fig.11 A piezoelectric actuator (not shown) is attached to a holding device 11487 of a measuring head 11485. A probe 11492 containing a cantilever 11494 or a lever arm 11494 and a measuring tip 11495 is fixed to the free end of the piezoelectric actuator 11490. The free end of the cantilever 11494 of the probe 11492 has a measuring tip 11495.

[0179] Next, combine Fig.12 and Fig.13 , will reveal options for positioning sensor 800, which can be used to measure disturbances in physical quantities, each of which affects the beam deviation of beam 11415 of repair device 11120. If compared to Fig.11 and Fig.12 and Fig.13 , repair device 11120 is only schematically illustrated at a higher level of abstraction. Fig.11 In addition to what is revealed in Fig.12 and Fig.13 Also disclosed are a beam blanker 11801 that can be used to blank the beam 11415, as well as an aperture 11802 and electrical coils 11803 and 11804 for deflecting the beam (ie, the optical device that forms the beam deflection unit 112).

[0180] exist Fig.12 In the case of, the sensor 800 is arranged outside the vacuum chamber 11442 of the repair device 11120. Fig.13In the case of, the sensor 800 is arranged inside the vacuum chamber 11442 of the repair device 11120. Combinations are possible, that is, some sensors may be arranged inside the vacuum chamber, while other sensors may be arranged outside the vacuum chamber.

[0181] Fig.14 and Fig.15 The high-precision mask repair operation that can be achieved by using the repair device 11120 of the aforementioned diagram is illustrated. Fig.14 In the first step shown, a mask defect 1471.1 in an absorber line 1453 on a substrate layer 1451 of a mask is determined with high precision. Using an inspection mode, an accurate determination of the extension of the defect 1471.1 is determined, including at least the tilt angle 1473.1 of the defect 1471.1. The position, the deviation from a target range 1475 of an edge position, and the extension of the defect can be determined with an accuracy of less than 1 nm, preferably even less than 0.5 nm. The missing amount of material to be deposited in a repair operation can be determined with high precision. In a repair step (manipulation mode), the defect 1471.1 is filled with, for example, chromium, using, for example, low-energy electron beam-assisted deposition of material from a precursor gas provided by a gas supply device to form a repaired defect 1477. This is done in Fig.15 . The performance of the repair operation is then verified by the device in inspection mode. In this way, the edge position of the resulting line 1453 and the tilt angle 1473.2 of the line edge can be obtained with high precision. It can thus be considered that the repair operation is performed very well within the specification requirements of the mask, including the strict requirements for EUV masks with edge positions below 0.5nm or even smaller. The steps of repair and verification can also be performed iteratively. This operation is not limited to missing material in the mask layer, but can also be similarly applied to remove excess material in the mask layer. In addition, the manipulation is not limited to mask repair, and also includes circuit editing operations at the processed wafer. In both instances, the layer material is removed by electron beam induced etching, or the layer material is deposited by electron beam induced deposition, and the endpoints need to be processed with high precision.

[0182] Fig.16 An exemplary embodiment of a charged particle beam device such as the charged particle beam device 100 described above is schematically illustrated.

[0183] Fig.16The charged particle device 161001 in the embodiment is a low energy corrected electron microscope with reduced aberrations, as described in German patent application DE 10 2019 214 936 filed on September 27, 2019, which is incorporated herein by reference. Typically, a low energy corrected electron microscope comprises correction means for chromatic aberration (CC), spherical aberration (CS) and selective field curvature (FC). The low energy corrected single beam charged particle microscope 161001 comprises a beamlet generator 161301 for generating a single primary charged particle beamlet 161003, an object illumination unit 161100 for irradiating an image subfield on a surface of a sample 11110 (e.g. a photolithography mask or a semiconductor wafer comprising semiconductor structures) arranged in an object plane 16101, thereby generating during use a secondary electron beamlet 161009 emitted from a focus 161605 of the primary beamlet 161003 within the image subfield. The subfields typically have a lateral extension of at least 5 μm, preferably 8 μm, 12 μm or more. The object illumination unit 161100 further comprises first to third electrostatic or magnetic lenses 161403, 161405 and 161407 and an objective lens 161102. The charged particle microscope 161001 further comprises a detection unit 161200 for acquiring a digital image of the image subfields on the sample surface during use. The detection unit 161200 comprises an electronic sensor 161207 and an optional electrostatic or electromagnetic deflection element 161205. The charged particle microscope 161001 further comprises an electromagnetic beam splitting system 161400 for guiding the primary beamlet 161003 along the primary beam path (solid line 161013) and guiding the secondary beamlet 161009 along the secondary beam path (dashed line 161011). The secondary beamlet 161009 focused by the objective lens 161102 propagates relative to the primary beamlet 161003 and is thus separated from the primary beamlet 161003 by the magnetic beam splitting system 161400. The charged particle microscope 161001 further comprises a long-stroke grating scanner 161110. The grating scanner 161110 (forming a beam deflection unit) comprises at least one first set of deflection electrodes 161111. The charged particle microscope 161001 further comprises a control unit 16800 (implementing the control unit 119 or the control unit 130). The charged particle microscope 161001 further comprises at least one first corrector 161601 for correcting the primary charged particle beamlet 161003. The charged particle system 161001 further comprises a correction system 161052 having a second optical axis 161050 forming a certain angle with the optical axis 16105. The beam splitter system 161400 directs the primary beamlet in the direction of the second optical axis 161050 to the correction system 161052. The correction system comprises an electrostatic mirror 161414, which reflects the primary beamlet back to the beam splitter system 161400.In one example, the second corrector 161602 is configured in the correction system 161052 and has a correction electrode 161612. The single beam charged particle microscope 161001 with low energy correction can perform electron imaging with kinetic energy below 400eV, preferably below 300eV, even more preferably below 200eV, or even more preferably below 150eV, and achieves high resolution below 2nm, preferably below 1.5nm, and even more preferably below 1nm by using primary electrons with low impact energy and a correction device for a low energy electron microscope.

[0184] The charged particle beam is again placed in a vacuum chamber ( Fig.16 The sensor may be arranged inside and / or outside the vacuum chamber, as previously described in conjunction with Fig.14 and Fig.15 discussed.

[0185] In summary, a technique has been disclosed that helps compensate for multiple disturbances caused by multiple physical quantities, which affect the beam offset of the beam of a charged particle beam device. This compensation is performed during an imaging mode or a manipulation mode, for example, for mask repair or adding circuits. In particular, this compensation is possible when the disturbance / beam offset is within a predetermined range. In addition, if the disturbance cannot be compensated, the imaging mode or the manipulation mode is stopped, for example, by blanking the beam and / or by closing a precursor gas supply valve, according to an example. A warning is output according to an example. Once the disturbance is resolved, the operation is restarted at the processing point where the stop occurs. Using the technology disclosed herein, the quality improvement of an imaging task or a manipulation task is achieved. The risk of damaging an expensive lithography mask or a semiconductor device subjected to manipulation can be reduced.

[0186] In addition, a technique has been disclosed that helps use sensor outputs of multiple sensors to predict the future behavior of a charged particle beam device. For example, the sensor outputs can be stored in a data repository, and multiple time series can be associated with each other. In this way, correlations can be found and repeated finger-shaped ripples can be identified. This can be used to predict the future behavior of a charged particle beam device. In this way, predictive maintenance information can be obtained, for example, by using a microphone to obtain an acoustic spectrum and / or acoustic noise pressure, for example, a continuously increasing noise level at certain frequencies in the acoustic spectrum can be detected, which can indicate a fault in one or more components of the charged particle beam device, such as a pump.

[0187] In various examples, a machine learning algorithm such as a deep neural network is used to analyze the sensor output. The training can be repeated from time to time based on the training data obtained during the calibration mode. In this way, the accuracy can be continuously improved. In addition, site-specific training can be performed based on site-specific calibration.

[0188] In summary, at least examples defined by the following terms are disclosed.

[0189] Item 1: A charged particle beam device, comprising a beam source, a beam deflection unit and a sample stage, wherein the beam deflection unit is configured to deflect a charged particle beam originating from the beam source to position the beam on the sample stage, the charged particle beam device comprising:

[0190] - one or more sensors configured to measure one or more disturbances of one or more physical quantities, each physical quantity affecting the beam deviation of the beam on the sample stage,

[0191] - at least one control unit configured to determine one or more compensation signals based on the sensor output of the one or more sensors to counteract the beam deviation,

[0192] Wherein the at least one control unit is configured to provide the one or more compensation signals to at least one of the beam source, the beam deflection unit, the sample stage or one or more compensator modules.

[0193] Clause 2: A charged particle beam device as described in clause 1,

[0194] Wherein the at least one control unit is configured to determine a predicted component of the beam offset based on sensor outputs of the one or more sensors, and to determine the one or more compensation signals based on the predicted component of the beam offset.

[0195] Clause 3: A charged particle beam device as described in clause 2,

[0196] wherein the sensor output of at least one of the one or more sensors comprises respective time series data,

[0197] Wherein the at least one control unit is configured to determine the prediction component based on an analysis of the time series data of the sensor output of at least one of the one or more sensors.

[0198] Clause 4: A charged particle beam device as described in clause 3,

[0199] The analysis of the time series data includes finding finger-like ripples of one or more predetermined disturbance events in the time series data, and / or applying a recurrent neural network, such as a long short-term memory network.

[0200] Clause 5: A charged particle beam device as described in clause 4,

[0201] wherein the at least one control unit is configured to selectively initiate a calibration phase,

[0202] Wherein, when operating in the calibration phase, the at least one control unit is configured to fill a repository with the finger ripples of the one or more disturbance events, or to obtain user input data indicating a corresponding one of the one or more disturbance events, for example based on identifying at least one of the corresponding repetitions of the finger ripples in the time series.

[0203] Clause 6: A charged particle beam device as described in clause 4 or 5,

[0204] wherein the at least one control unit is configured to selectively initiate a calibration phase,

[0205] Wherein, when operating in the calibration phase, the at least one control unit is configured to train a prediction model based on the time series data measured during the calibration phase to find the finger ripples and thereby enable the prediction model to determine the prediction component.

[0206] Clause 7: A charged particle beam device as described in any of the preceding clauses,

[0207] The at least one control unit is further configured to predict an operating accuracy of the charged particle beam device during a prediction duration based on at least one of the sensor output or the one or more compensation signals.

[0208] Clause 8: A charged particle beam device as described in clause 7,

[0209] The at least one control unit is further configured to selectively suspend operation of the charged particle beam device based on accuracy of operation, such as by blanking the beam.

[0210] Clause 9: A charged particle beam device as described in any of the preceding clauses,

[0211] wherein the one or more disturbances comprises a plurality of disturbances,

[0212] The at least one control unit is configured to determine the one or more compensation signals based on mutual dependencies between the plurality of disturbances.

[0213] Clause 10: A charged particle beam device as described in clause 9,

[0214] The at least one control unit is configured to determine the one or more compensation signals based on a mutual dependency between the temperature-induced disturbance and the pressure-induced disturbance.

[0215] Clause 11: A charged particle beam device as described in any of the preceding clauses,

[0216] Wherein the at least one control unit is configured to determine the one or more compensation signals based on a pre-trained algorithm.

[0217] Clause 12: A charged particle beam device as described in clause 11,

[0218] The pre-training algorithm includes a deep neural network, such as a convolutional neural network.

[0219] Clause 13: A charged particle beam device as described in clause 11,

[0220] The pre-training algorithm includes a machine learning algorithm.

[0221] Clause 14: A charged particle beam device as described in any of the preceding clauses,

[0222] Wherein the at least one control unit is configured to determine the one or more compensation signals based on pre-parameterized functional dependencies.

[0223] Clause 15: A charged particle beam device as described in any of the preceding clauses,

[0224] Wherein the at least one control unit is configured to determine the one or more compensation signals using a lookup table linking the sensor output with the one or more compensation signals.

[0225] Clause 16: A charged particle beam device as described in clause 15,

[0226] Wherein the lookup table is retrieved from a device specific repository associated with the charged particle beam device.

[0227] Clause 17: A charged particle beam device as described in clause 15,

[0228] The lookup table is retrieved from a cloud storage repository associated with a plurality of charged particle beam devices.

[0229] Clause 18: A charged particle beam device as described in any of the preceding clauses,

[0230] The multiple physical quantities are selected from the group consisting of: acoustic vibration, vibration, pressure, humidity, temperature, laminar airflow, turbulent airflow, differential quantity, rate of change of physical quantity, vector, and scalar.

[0231] Clause 19: A charged particle beam device as described in any of the preceding clauses,

[0232] The one or more sensors include at least one sensor for measuring the temperature or pressure of the coolant.

[0233] Clause 20: A charged particle beam device as described in any of the preceding clauses,

[0234] At least one of the one or more sensors is disposed within a vacuum chamber of the charged particle beam repair device.

[0235] Clause 21: A charged particle beam device as described in any of the preceding clauses,

[0236] At least one of the one or more sensors is configured outside the vacuum chamber of the charged particle beam repair device.

[0237] Clause 22: A charged particle beam device as described in any of the preceding clauses,

[0238] The one or more sensors include at least one sensor for measuring a pressure difference or a temperature difference between two or more parts of the charged particle beam repair device.

[0239] Clause 23: A charged particle beam device as described in any of the preceding clauses,

[0240] The one or more perturbations are selected from the group consisting of: direct perturbations that affect the beam deflection by deflecting the beam; indirect perturbations that affect the beam deflection by impacting one or more parts of the charged particle beam device.

[0241] Clause 24: A charged particle beam device as described in any of the preceding clauses,

[0242] The beam offset includes at least one of a placement offset or a focus offset of the beam.

[0243] Clause 25: A charged particle beam device as described in any of the preceding clauses,

[0244] Wherein the at least one control unit is configured to monitor the sensor output of at least one of the one or more sensors or another sensor output of at least one other sensor and selectively blank the beam based on the monitoring.

[0245] Clause 26: A charged particle beam device as described in clause 25,

[0246] Wherein the at least one control unit is configured to selectively blank the beam with a lower delay than said determining the one or more compensation signals.

[0247] Clause 27: A charged particle beam device as described in any of the preceding clauses,

[0248] Wherein the at least one control unit is configured to provide the one or more compensation signals by operating the charged particle beam device in a manipulation mode, such as an electron beam induced etching or deposition mode, the manipulation mode comprising repairing or editing a semiconductor device on a wafer mounted on the sample stage.

[0249] Clause 28: A charged particle beam device as described in any of the preceding clauses,

[0250] The charged particle beam device is a charged particle beam repair device.

[0251] Clause 29: A charged particle beam device as described in any of the preceding clauses,

[0252] The charged particles are electrons or ions, such as helium ions or neon ions.

[0253] Clause 30: A charged particle beam device as described in any of the preceding clauses,

[0254] The charged particle beam device is a combined focused ion beam and electron microscope cross beam device.

[0255] Clause 31: A charged particle beam device as described in any of the preceding clauses,

[0256] The charged particle beam device is a charged particle beam repair device,

[0257] The charged particle beam repair device further comprises a precursor gas source,

[0258] wherein the at least one control unit is configured to provide control signals to the beam source, the beam deflection unit and the precursor gas source to implement electron beam induced manipulation of a sample mounted to the sample stage,

[0259] Wherein the at least one control unit is configured to provide the one or more compensation signals during the electron beam induced manipulation.

[0260] Clause 32: A charged particle beam device as described in any of the preceding clauses,

[0261] The at least one control unit is configured to provide the one or more compensation signals when the charged particle beam apparatus is operated in an imaging mode, the imaging mode comprising imaging a structure of the sample mounted to the sample stage.

[0262] Clause 33: A charged particle beam device as described in any of the preceding clauses,

[0263] The at least one control unit determines the one or more compensation signals according to a linear or non-linear dependency of the one or more compensation signals on the sensor output.

[0264] Clause 34: A charged particle beam device as described in any of the preceding clauses,

[0265] wherein the one or more disturbances comprises a plurality of disturbances,

[0266] The one or more physical quantities include multiple physical quantities.

[0267] Clause 35: A charged particle beam device as described in any of the preceding clauses,

[0268] The one or more compensator modules are selected from the group consisting of: external (i.e., outside the vacuum chamber or housing of the charged particle beam device) coils for applying a magnetic field; external electric field plates for applying an electric field; multiple Helmholtz coil pairs; active cooling or heating elements; active damping elements; pressure control elements, such as pumps.

[0269] Clause 36: A charged particle beam apparatus comprising a beam source, a beam deflection unit and a sample stage, the beam deflection unit being configured to deflect a beam originating from the beam source to position the beam on the sample stage, the charged particle beam apparatus comprising:

[0270] - one or more sensors configured to measure one or more disturbances of one or more physical quantities, each physical quantity affecting the beam deviation of the beam on the sample stage; and

[0271] - at least one control unit configured to determine metadata indicative of one or more compensation operations based on the sensor output of the one or more sensors to counteract beam deviation in image data acquired by the charged particle beam device operating in an imaging mode, and to store the metadata in association with the image data.

[0272] Clause 37: A charged particle beam device as described in clause 36,

[0273] The one or more compensation operations are selected from the group consisting of: imaging shift; rotation; tilt; contrast enhancement; blur reduction.

[0274] Clause 38: A method comprising:

[0275] - monitoring of physical quantities causing disturbances in the beam of a charged particle beam device,

[0276] - Based on the monitoring, compensating for the disturbance.

[0277] Clause 39: A method as described in Clause 38,

[0278] Wherein the compensation of the disturbance comprises applying a voltage or a current to an electron-optical device of a beam deflection unit of the charged particle beam apparatus to move the beam in a direction opposite to the beam deviation caused by the disturbance.

[0279] Clause 40: A method as described in clause 38 or 39,

[0280] Wherein the compensating or reducing the disturbance comprises moving a sample stage of the charged particle beam apparatus in a direction of the beam deviation caused by the disturbance.

[0281] Clause 41: A method as described in any one of clauses 38 to 40,

[0282] Wherein the time delay between the monitoring and the compensation or reduction is less than 50 milliseconds, optionally less than 500 milliseconds, further optionally less than 5 seconds.

[0283] Clause 42: A method as described in any one of clauses 38 to 41,

[0284] Wherein the compensating or reducing is performed when the charged particle beam device is operated in a steering mode comprising electron beam induced etching of material from a wafer mask or deposition of material on a wafer mask.

[0285] Clause 43: A method as described in any one of clauses 38 to 42, further comprising:

[0286] - Based on the monitoring, selectively suspending operation of the charged particle beam device.

[0287] Clause 44: A method as described in Clause 43,

[0288] Wherein the selectively suspending operation of the charged particle beam device comprises blanking the beam.

[0289] Clause 45: The method as described in Clause 43 or 44, further comprising:

[0290] - Based on the monitoring, selecting between performing the disturbance compensation and performing the abort operation.

[0291] Clause 46: A method of manipulating or imaging a sample mounted to a sample stage of a charged particle beam apparatus, the charged particle beam apparatus comprising a beam source, a beam deflection unit and the sample stage, the beam deflection unit being configured to deflect a beam of charged particles originating from the beam source to position the beam on the sample stage,

[0292] The method includes:

[0293] - obtaining a sensor output of one or more sensors of the charged particle beam device, the one or more sensors measuring one or more disturbances of one or more physical quantities, each physical quantity affecting a beam deviation of the beam on the sample stage,

[0294] - determining one or more compensation signals based on the sensor output of the one or more sensors to counteract the beam deviation,

[0295] - providing the one or more compensation signals to at least one of the beam source, the beam deflection unit, the sample stage or one or more compensator modules.

[0296] Clause 47: The method of clause 46, wherein the method is performed by a control unit of the charged particle beam apparatus of clause 1.

[0297] Item 48: A method for post-processing image data acquired by a charged particle beam apparatus, the charged particle beam apparatus comprising a beam source, a beam deflection unit and a sample stage, the beam deflection unit being configured to deflect a beam of charged particles originating from the beam source to position the beam on the sample stage,

[0298] The method includes:

[0299] - obtaining a sensor output from one or more sensors of the charged particle beam device, the one or more sensors measuring one or more perturbations of one or more physical quantities, each physical quantity affecting a beam deviation of the beam on the sample stage,

[0300] - determining metadata indicative of one or more compensation operations to counteract beam drift in image data acquired by the charged particle beam apparatus operating in an imaging mode based on the sensor output of the one or more sensors; and

[0301] - post-processing the image data based on the metadata and in accordance with the one or more compensation operations.

[0302] Clause 49: The method of clause 48, wherein the method is at least partially performed by a control unit of the charged particle beam apparatus of clause 36.

[0303] Although the invention has been shown and described with respect to certain preferred specific embodiments, equivalents and modifications will occur to those skilled in the art upon reading and understanding this specification. The invention includes all such equivalents and modifications and is limited only by the scope of the appended claims.

[0304] For illustration, the various examples described above have been disclosed in the context of a charged particle beam repair device that uses electron beam induced sample manipulation (i.e., EBID and / or EBIE) to perform repair tasks. Typically, repair tasks can also be accomplished by using the physical action of ions, i.e., FIB etching. In addition, the techniques disclosed herein are not limited to charged particle beam repair devices, but can also be used to compensate for disturbances during circuit editing operations at a semiconductor wafer, or during inspection or measurement tasks during operation in an imaging mode of a corresponding charged particle beam device.

[0305] For illustration, the various examples above have been disclosed in the context of charged particle beam devices that employ charged particles such as electrons or ions. Similarly, the techniques disclosed herein can be applied to uncharged particle beam devices, such as for photon-based microscopes. Herein, disturbances can be caused by physical quantities such as earthquake changes, sound, pressure changes, wind speed changes, humidity changes, temperature, etc. The corresponding beam device can be, for example, a laser, an X-ray survey tool, etc. Compensation can be achieved by moving the sample stage to offset the beam offset, such as in combination with Figures 1 to 5 Explained.

[0306] In addition, techniques for actively compensating beam deviations caused by physical quantity disturbances have been disclosed. Such techniques can be applied together with passive shielding. For example, acoustic vibrations, thermal drift, laminar or turbulent airflow can be reduced by encapsulating beam-related components of a charged particle beam device in a housing. Noise absorbing materials can be attached to the housing. Passive or active vibration reduction systems can be used to support the housing on the floor.

Claims

1. A charged particle beam repair device (100, 11120, 11410, 161001), comprising a beam source (111, 11412), a beam deflection unit (112, 11417), a precursor gas source (11456, 11466, 11476, 11450, 11460, 11470, 11452, 11462, 11472) and a sample stage (114, 11412). 402), the beam deflection unit (112, 11417) is configured to deflect the beam (90, 91, 92, 93, 94, 95, 11415, 161003, 161009) of charged particles originating from the beam source to position the beam on the sample stage (113, 11402), and the charged particle beam repair device (100, 11120, 11410, 161001) comprises: - a plurality of sensors (121, 122, 800) configured to measure a plurality of disturbances of a plurality of physical quantities, wherein each physical quantity affects a beam deviation (71, 72, 81) of the beam (90, 91, 92, 93, 94, 95) on the sample stage (114, 11402), - at least one control unit (119, 130, 11425, 16800) configured to determine one or more compensation signals (165) to counteract the beam deviation (71, 72, 81) based on the sensor outputs (161, 162) of the plurality of sensors (121, 122, 800), wherein the at least one control unit (119, 130, 11425, 16800) is configured to provide control signals to the beam source (111, 11412), the beam deflection unit (112, 11417) and the precursor gas source (11456, 11466, 11476, 11450, 11460, 11470, 11452, 11462, 11472) to implement electron beam induced manipulation of a sample (11110) mounted on the sample stage (113, 11402), The at least one control unit (119, 130, 11425, 16800) is configured to provide the one or more compensation signals (165) to at least one of the beam source (111, 11412), the beam deflection unit (112, 11417), the sample stage (114, 11402) or one or more compensator modules during the electron beam induced manipulation.

2. The charged particle beam repair device (100, 11120, 11410, 161001) according to claim 1, Wherein the at least one control unit (119, 130, 11425, 16800) is configured to determine a predicted component of the beam offset (71, 72, 81) based on the sensor output (161, 162) of the plurality of sensors (121, 122, 800), and to determine the one or more compensation signals (165) based on the predicted component of the beam offset (71, 72, 81).

3. The charged particle beam repair device (100, 11120, 11410, 161001) according to claim 2, wherein the sensor output (161, 162) of at least one of the plurality of sensors (121, 122, 800) comprises respective time series data (310), The at least one control unit (119, 130, 11425, 16800) is configured to determine the prediction component based on an analysis of the time series data (310) of the sensor output (161, 162) of at least one of the plurality of sensors (121, 122, 800).

4. The charged particle beam repair device (100, 11120, 11410, 161001) according to claim 3, The analysis of the time series data (310) includes searching for finger-shaped ripples (312) of one or more predetermined disturbance events (311) within the time series data (310).

5. The charged particle beam repair device (100, 11120, 11410, 161001) according to claim 4, wherein the at least one control unit (119, 130, 11425, 16800) is configured to selectively initiate a calibration phase (6005), in, When operating in the calibration phase (6005), the at least one control unit (119, 130, 11425, 16800) is configured to populate a repository with the finger ripples (312) of the one or more disturbance events (311) based on identifying corresponding repetitions of the finger ripples (312) in the time series data or obtaining at least one of the user input data indicating a corresponding one of the one or more disturbance events (311).

6. The charged particle beam repair device (100, 11120, 11410, 161001) according to claim 4 or 5, wherein the at least one control unit (119, 130, 11425, 16800) is configured to selectively initiate a calibration phase (6005), in, When operating in the calibration phase (6005), the at least one control unit (119, 130, 11425, 16800) is configured to train a prediction model based on the time series data (310) measured during the calibration phase (6005) to find the finger ripples (312) and thereby enable the prediction model to determine the prediction component.

7. A charged particle beam repair device (100, 11120, 11410, 161001) as claimed in any one of the preceding claims, Wherein the at least one control unit (119, 130, 11425, 16800) is further configured to predict the operating accuracy of the charged particle beam repair device (100, 11120, 11410, 161001) during a predicted duration based on the sensor output (161, 162) or at least one of the one or more compensation signals (165).

8. A charged particle beam repair device (100, 11120, 11410, 161001) as claimed in any one of the preceding claims, The at least one control unit (119, 130, 11425, 16800) is configured to determine the one or more compensation signals (165) based on the mutual dependencies between the plurality of disturbances.

9. A charged particle beam repair device (100, 11120, 11410, 161001) as claimed in any one of the preceding claims, Wherein the at least one control unit (119, 130, 11425, 16800) is configured to determine the one or more compensation signals (165) based on a pre-trained algorithm.

10. The charged particle beam repair device (100, 11120, 11410, 161001) according to any one of the preceding claims, Wherein the at least one control unit (119, 130, 11425, 16800) is configured to determine the one or more compensation signals based on pre-parameterized functional dependencies.

11. A charged particle beam repair device (100, 11120, 11410, 161001) as claimed in any one of the preceding claims, Wherein the at least one control unit (119, 130, 11425, 16800) is configured to determine the one or more compensation signals using a lookup table linking the sensor output (161, 162) with the one or more compensation signals (165).

12. A charged particle beam repair device (100, 11120, 11410, 161001) as claimed in any one of the preceding claims, The multiple physical quantities are selected from the group consisting of: acoustic vibration, vibration, pressure, humidity, temperature, laminar airflow, turbulent airflow, differential quantity, rate of change of physical quantity, vector, and scalar.

13. A charged particle beam repair device (100, 11120, 11410, 161001) as claimed in any one of the preceding claims, The plurality of sensors (121, 122, 800) include at least one sensor for measuring the temperature or pressure of the cooling fluid.

14. A charged particle beam repair device (100, 11120, 11410, 161001) as claimed in any one of the preceding claims, At least one of the multiple sensors (121, 122, 800) is configured in the vacuum chamber (110) of the charged particle beam repair device (100, 11120, 11410, 161001).

15. The charged particle beam repair device (100, 11120, 11410, 161001) as claimed in any one of the preceding claims, The plurality of sensors (121, 122, 800) include at least one sensor for measuring a pressure difference or a temperature difference between two or more parts of the charged particle beam repair device (100, 11120, 11410, 161001).

16. A charged particle beam repair device (100, 11120, 11410, 161001) as claimed in any one of the preceding claims, The multiple disturbances are selected from a group comprising: direct disturbances that affect the beam deviation (71, 72, 81) by deflecting the beam; indirect disturbances that affect the beam deviation (71, 72, 81) by impacting one or more parts of the charged particle beam repair device (100, 11120, 11410, 161001).

17. A charged particle beam repair device (100, 11120, 11410, 161001) as claimed in any one of the preceding claims, The beam offset (71, 72, 81) includes at least one of a placement offset (71, 72, 81) or a focus offset (71, 72) of the beam.

18. The charged particle beam repair device (100, 11120, 11410, 161001) according to any one of the preceding claims, The at least one control unit (119, 130, 11425, 16800) is configured to monitor the sensor output (161, 162) of at least one of the plurality of sensors (121, 122, 800) or another sensor output (161, 162) of at least one other sensor, and to selectively blank the beam based on the monitoring.

19. The charged particle beam repair device (100, 11120, 11410, 161001) according to any one of the preceding claims, Wherein the at least one control unit (119, 130, 11425, 16800) is configured to provide the one or more compensation signals (165) while the charged particle beam repair device (100, 11120, 11410, 161001) operates in a manipulation mode, which comprises repairing or editing a semiconductor device on a chip mounted on the sample stage (114, 11402).

20. A charged particle beam device (100, 11120, 11410, 161001), comprising a beam source, a beam deflection unit (112, 11417) and a sample stage (114, 11402), wherein the beam deflection unit (112, 11417) is configured to deflect a beam originating from the beam source so as to position the beam on the sample stage (114, 11402), the charged particle beam device (100, 11120, 11410, 161001) comprising: - a plurality of sensors (121, 122, 800) configured to measure a plurality of disturbances of a plurality of physical quantities, wherein each physical quantity affects a beam deviation (71, 72, 81) of the beam (90, 91, 92, 93, 94, 95) on the sample stage (114, 11402); and - at least one control unit (119, 130, 11425, 16800) configured to determine metadata indicating one or more compensation operations based on sensor outputs (161, 162) of the plurality of sensors (121, 122, 800) to offset the beam offset (71, 72, 81) in imaging data acquired by the charged particle beam device operating in imaging mode, and to store the metadata associated with the image data.

21. A method for manipulating a sample (11110) mounted on a sample stage of a charged particle beam repair device (100, 11120, 11410, 161001), the charged particle beam repair device comprising a beam source, a beam deflection unit, a precursor gas source and the sample stage, the beam deflection unit being configured to deflect a charged particle beam originating from the beam source to position the beam on the sample stage, The method includes: - obtaining sensor outputs of a plurality of sensors of the charged particle beam repair device, the plurality of sensors measuring a plurality of disturbances of a plurality of physical quantities, each physical quantity affecting a beam deviation of the beam on the sample stage, - determining one or more compensation signals to counteract the beam deviation based on the sensor outputs of the plurality of sensors, - providing control signals to the beam source, the beam deflection unit and the precursor gas source to perform electron beam induced manipulation of the sample, - providing the one or more compensation signals to at least one of the beam source, the beam deflection unit, the sample stage or one or more compensator modules during the electron beam induced steering.

22. The method of claim 21, wherein the method is executed by a control unit of the charged particle beam repairing device of claim 1.

23. A method for post-processing image data acquired by a charged particle beam device, the charged particle beam device comprising a beam source, a beam deflection unit and a sample stage, the beam deflection unit being configured to deflect a charged particle beam originating from the beam source to position the beam on the sample stage, The method includes: - obtaining sensor outputs from a plurality of sensors of the charged particle beam device, the plurality of sensors measuring a plurality of perturbations of a plurality of physical quantities, each physical quantity affecting a beam deviation of the beam on the sample stage, - determining metadata indicative of one or more compensation operations to counteract beam drift in imaging data acquired by the charged particle beam apparatus operating in an imaging mode based on the sensor outputs of the plurality of sensors; and - post-processing the image data based on the metadata and in accordance with the one or more compensation operations.

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