Device and method for examining and / or processing a sample

Abstract

The present invention relates to an apparatus (2400, 2600) for inspecting and / or processing a sample (400, 2010), the apparatus comprising: (a) a scanning particle microscope (2410) for providing a charged particle beam (840) that can be directed onto the surface of the sample (400, 2010); (b) a scanning probe microscope (2470) having a deflectable probe (200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670, 2600); (c) wherein a detection structure (230, 530, 1030, 1130, 1330, 1530, 1630, 1690, 2630) is attached to the deflectable probe (200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670, 2600).

Description

[0001] This patent application claims the benefit of German Patent Application DE 10 2018 210 098.5, filed on June 21, 2018, entitled "Vorrichtung und Verfahren zum Untersuchen und / oder zum Bearbeiten einer Probe", which is assigned to its assignee and is hereby incorporated by reference in its entirety. 1. Field of the Invention

[0002] The present invention relates to an apparatus and a method for examining and / or processing a sample. In particular, the present invention relates to an apparatus and a method for moving particles of a sample. 2. Background of the Invention

[0003] Due to the increasing integration density in the semiconductor industry, lithography masks have to image increasingly smaller structures on wafers. In lithography, the trend of increasing integration density can be addressed by shifting the exposure wavelength of the lithography system to an even shorter wavelength. Currently, an ArF (argon fluoride) excimer laser emitting a wavelength of approximately 193 nm is frequently used as a light source in lithography systems or lithography technology systems.

[0004] Particles from the surrounding environment may deposit on a lithography mask, a photomask, or a simple mask and impair the imaging function of the mask. As a standard, during mask manufacturing and during the operation of the mask, particles are removed from the surface of the mask by a cleaning step. Generally, particles may appear on a sample and have a negative impact on the function of the sample.

[0005] The reduced structure size of the lithography mask increases the difficulty of the cleaning process. In addition, due to the reduced exposure wavelength, even smaller foreign matter or dirt particles adsorbed on the surface of the mask become visible during the exposure process on the wafer.

[0006] Some documents that mention the examination of the movement of nanoparticles by means of a nano - manipulator or a micro - manipulator (e.g., the measuring tip of a scanning probe microscope) are mentioned in an exemplary manner below: H.H. Pieper: Thesis of the University of Osnabrück in 2012, "Morphology and electric potential of pristine and gold covered surfaces with fluorite structure"; S. Darwich et al.: Beilstein J. Nanotechnol. Vol. 2, pp. 85 - 98 in 2011, "Manipulation of gold colloidal nanoparticles with atomic force microscopy in dynamic mode: influence of particle - substrate chemistry and morphology, and operating conditions"; H.H. Pieper et al.: Phys. Chemistry Chemical Physics, Vol. 14, pp. 15361ff in 2013, "Morphology and nanostructure of CeO2(111) surfaces of single crystals and Si(111) supported ceria films"; E. Gallagher et al.: BACUS, Vol. 3, No. 3, pp. 1 - 8 in 2013, "EUVL mask repair: expanding options with nanomachining"; M. Martin et al.: Appl. Phys. Lett., Vol. 72, No. 11, pp. 1505 - 1507 in September 1998, "Manipulation of Ag nanoparticles utilizing non - contact atomic force microscopy"; P.J.Durston et al., "Manipulation of passivated gold clusters on graphite with the scanning tunneling microscope," Appl. Phys. Lett., vol. 72, no. 2, pp. 176 - 178, January 1998; R. Requicha, "Nanomanipulation with the atomic force microscope," Nanotechnology Online, ISBN: 9783527628155; C. Baur et al., "Nanoparticle manipulation by mechanical pushing: underlying phenomena and real-time monitoring," Nanotechnology, vol. 9, pp. 360 - 364, 1998; J.D. Beard et al., "An atomic force microscope nanoscalpel for nanolithography and biological applications," Nanotechnology, vol. 20, no. 445302, pp. 1 - 10, 2009; US 6812460 B1; and US 8696818 B2.

[0007] The documents specified in an exemplary manner below relate to the manufacture of TEM samples by means of an in-situ lifting method: J. Mayer et al.: "TEM sample preparation and FIB-induced damage" in MRS Bulletin, Vol. 32, pp. 400-407, May 2007; B. Myers: "TEM Sample Preparation with the FIB / SEM" from the Nuance Center of Northwestern University - Evanston in 2009; M. Schaffer et al.: "Sample preparation for atomic STEM at low voltages by FIB" in Ultramicroscopy, Vol. 114, pp. 62-71, 2012; and US2017 / 0 256 380A1.

[0008] In the literature "A novel AFM / STM / SEM system" in Rev. Sci. Instrum, Vol. 65, No. 9, pp. 2853-2954, September 1994, the authors A.V. Ermakov and E.L. Garfunkel described the use of an electron beam to detect the vibration of the cantilever of an AFM.

[0009] U.S. Patent Document US 4,440,475 describes a combination of a scanning electron microscope and an optical microscope, where some optical beams are guided in the column of the scanning electron microscope when the optical microscope is operated in an operation mode with higher resolution.

[0010] US 7,395,727 B2 describes a nanomanipulator that allows detecting the landing of its tip on the sample surface.

[0011] The combination of a scanning particle microscope and a scanning probe microscope in one instrument requires separating the spaces of the two microscopes for space reasons, so the switching between the operations of the two microscopes becomes complicated and slow. If the two microscopes are arranged closely adjacent to each other, a compromise must be found in the performance of the two microscopes.

[0012] Accordingly, the present invention solves the problem of specifying devices and methods that facilitate the improvement of the inspection and / or processing of samples. 3. Summary of the Invention

[0013] According to an exemplary embodiment of the present invention, this problem is solved by a device as described below and by a method as described below. In a first embodiment, a device for inspecting and / or processing a sample comprises: (a) a scanning particle microscope for providing a charged particle beam, which can be directed onto the surface of the sample; (b) a scanning probe microscope having a deflectable probe; (c) wherein a detection structure is attached to the deflectable probe.

[0014] The device according to the present invention can have a compact construction because, in a manner similar to a conventional optical pointer system for determining the probe deflection of a scanning probe microscope, the charged particle beam of the scanning particle microscope is used in combination with the detection structure attached to the probe of the scanning probe microscope. The interaction region of the probe of the scanning probe microscope with the charged particle beam of the scanning particle microscope can overlap without having to make a compromise regarding the capabilities of the two microscopes. In addition, it is possible to switch very quickly between the scanning particle microscope operation mode and the scanning probe microscope operation mode. In particular, the charged particle beam of the scanning particle microscope can be used to monitor the approach of the probe of the scanning probe microscope to the sample and / or the processing of the sample using the probe.

[0015] The scanning particle microscope can be configured to perform at least one of the following elements: directing the charged particle beam onto the detection structure, performing a linear scan of the charged particle beam over the detection structure, and scanning the charged particle beam over the detection structure.

[0016] The material composition of the detection structure can be different from the material composition of the deflectable probe. The different material compositions of the detection structure and the probe result in a change in the secondary electron yield or a change in the backscattering coefficient of the backscattered electrons, which facilitates the detection of the deflection of the probe of the scanning probe microscope.

[0017] The detection structure can have a cylindrical, conical, rod-shaped or n-sided structure, where n≥3.

[0018] The detection structure can be attached to the front side of the probe, and the measuring tip can be attached to the back side of the probe.

[0019] The detection structure can include at least two separate adjacent materials having different atomic numbers.

[0020] At least two separate adjacent materials of the detection structure can be separated along the longitudinal axis of the deflectable probe.

[0021] The detection structure can be configured to optimize the emission of charged secondary electrons and / or backscattered electrons.

[0022] The detection structure can include a detection region configured to optimize the emission of charged secondary electrons and / or backscattered electrons.

[0023] In the case of an undeflected probe, the detection area can be aligned such that it is at an angle of ± undeflected with respect to the charged particle beam.

[0024] The detection area can be implemented to decouple the measurement signal generated by the detection area from the incident surface of the charged particle beam on the detection area at a distance that is at least 10, preferably at least 50, more preferably at least 100, and most preferably at least 500 beam diameters of the charged particle beam.

[0025] The detection area fulfills at least two functions. First, it optimizes the measurement signal of the detection area caused by the charged particle beam. Second, the detection area simplifies the adjustment of the charged particle beam on the probe. On the one hand, this is achieved by deliberately defocusing the charged particle beam with respect to the detection area, and on the other hand, by adjusting the tolerance of the charged particle beam with respect to the longitudinal axis of the probe. In the first exemplary embodiment described herein, the charged particle beam is preferably directed as a fixed beam onto the detection area of the probe.

[0026] The beam diameter of the charged particle beam is defined as the width at which the intensity has dropped to half of the maximum intensity, i.e., the full width at half maximum (FWHM) width of the intensity distribution.

[0027] The detection area can comprise 90%, preferably 50%, more preferably 30%, and most preferably 10% of the width of the probe.

[0028] Like the focused beam of an optical pointer system, the charged particle beam in the first exemplary embodiment described uses a relatively large percentage of the detection.

[0029] The size of the detection area can facilitate the use of the deflection of a beam detection probe, the cross-sectional area of which is greater than 10 nm 2 preferably 50 nm 2 more preferably 100 nm 2 and most preferably greater than 500 nm 2 .

[0030] The cross-sectional area of the charged particle beam refers to the full width at half maximum (FWHM) of its intensity profile.

[0031] This embodiment facilitates the deliberate defocusing of the charged particle beam with respect to the detection area of the probe. Thus, the spatial dependence of the measurement signal induced by the detection area due to the charged particle beam can be reduced.

[0032] The detection area can have a rectangular embodiment. Additionally, the detection area can be arranged at an angular range of 60° to 90°, preferably 70° to 90°, more preferably 80° to 90°, and most preferably 85° to 90° with respect to the surface of the probe.

[0033] Due to this embodiment of the detection region, an optical pointer system of a conventional scanning probe microscope can be approximately reproduced by means of a charged particle beam and a correspondingly arranged detector.

[0034] The detection structure and the probe can be manufactured in one piece. However, the probe and the detection structure can also be manufactured separately and the detection structure can be applied to the probe, for example, by bonding, in a second step. In addition, a notch can be provided in the probe into which the detection structure can be inserted.

[0035] The surfaces of the charged particle beam and the probe can include an angular range of 60 to 120 grains, preferably 70 to 110, more preferably 80 to 100, and most preferably 85 to 95.

[0036] Since the probe is arranged substantially horizontally, the sample can likewise be arranged horizontally. Thus, large samples, such as wafers or lithography masks, can be easily fixed and precisely positioned relative to the probe of a scanning probe microscope and / or the charged particle beam of a scanning particle microscope.

[0037] Here and elsewhere in this application, the expression "substantially" means an indication of a measurement variable within its error tolerance when measured using a measuring instrument according to the prior art.

[0038] The detection structure can have a material composition optimized for the emission of secondary electrons. For this purpose, materials with a high atomic number, such as gold, are advantageous, for example.

[0039] The detection region can have a curvature. The curvature of the detection region can be implemented to linearize the measurement signal of the deflection of the probe.

[0040] The deflection of the probe typically results in a strong, especially non-linear, change in the measurement signal of the detection region. By appropriately designing the closed-loop control of the vibration of the probe, this non-linearity can be compensated. However, it is also possible to select the surface form or curvature of the detection region such that there is actually a linear relationship between the deflection of the probe and the measurement signal generated by the detection region arranged on the probe. In this exemplary embodiment, the translational invariance of the charged particle beam above the detection region is abandoned.

[0041] The scanning particle microscope can be implemented to direct a fixed charged particle beam onto the detection region.

[0042] The detection structure can include at least one planar element, and the normal vector of the planar element can be directed substantially parallel or anti-parallel to the longitudinal axis of the deflectable probe.

[0043] At least one planar element may include a rectangular structure that extends over a majority of the width of the probe. The majority of the width of the probe represents a width portion of the probe that is greater than 50% of the width of the probe.

[0044] The detection structure may be attached to the dorsal side of the deflectable probe. The measurement tip may be attached to the detection structure.

[0045] The detection structure may include at least two planar elements that are arranged along the longitudinal axis of the deflectable probe. The at least two planar elements may be arranged parallel to each other. The at least two planar elements may have different heights. The at least two planar elements may include a rectangular structure.

[0046] The scanning particle microscope may be implemented to scan a charged particle beam along the longitudinal axis of the deflectable probe.

[0047] The detection structure and the measurement tip may be attached to the same side of the deflectable probe. The detection structure and the measurement tip may be attached to the dorsal side of the deflectable probe. The measurement tip may be attached to the detection structure.

[0048] The detection structure may include at least one marker.

[0049] At least one marker may be implemented to cause a change in position in the image of the scanning particle microscope in the case of probe deflection, the change in position allowing the deflection of the probe to be determined.

[0050] In the above first exemplary embodiment of the detection structure in the form of a detection area, an out-of-focus charged particle beam is typically fixedly positioned on the detection area. In a second exemplary embodiment, a focused electron beam is scanned over the area of the probe on which at least one marker is arranged. The deflection of the probe is detected by a lateral shift of at least one marker in the marker image. The advantage of this exemplary embodiment of the detection structure is that a detector (i.e., a detector in the lens) within the column of the scanning particle microscope can be used to detect the deflection of the probe. This promotes a compact embodiment of the above device. The scanning particle microscope operates in a scanning mode for the purpose of analyzing the sample and / or the probe or the deflection of the probe. This means that the settings of the scanning particle microscope only need to be slightly changed between scanning the sample or the lithographic element and scanning the probe. This promotes a quick switch between scanning the element and scanning the probe.

[0051] The at least one marker may be implemented as a tip and may be arranged on the surface of the probe on which the charged particle beam is incident. The at least one marker may include a material different from the material of the probe. In particular, the marker may include a material that optimizes the material contrast between the probe and the at least one marker.

[0052] Thus, when imaging a region of a marker or a probe including the marker, the imaging of the marker produces material contrast in addition to topological contrast.

[0053] The detection structure may include at least two markers having different heights from each other. The at least two markers may be arranged on a line extending substantially perpendicular to the longitudinal axis of the probe.

[0054] Two markers having different heights arranged on the probe facilitate the determination of the lateral offset of the probe in the case of probe deflection by differential measurement, which allows an increase in accuracy with which the deflection of the probe can be determined. In particular, in the case of a detection structure implemented in the form of two markers, a reference measurement can be avoided.

[0055] The device according to the invention may also have an optical light pointer system, and the detection structure may include a reflective structure which is implemented to reflect the optical radiation of the optical light pointer system, and which may be arranged at an angle other than zero with respect to the front side of the deflectable probe.

[0056] This embodiment facilitates the use of a charged particle beam and the probe of a scanning probe microscope to simultaneously or sequentially inspect and / or process a sample in a common or at least partially overlapping interaction region of the scanning particle microscope and the scanning probe microscope with the sample. In addition, this embodiment allows a first tool to process the sample and allows a second tool to inspect or monitor the processing process.

[0057] The reflective structure may include a mirror. The reflective structure may include a metal or a metal tempering layer. The angle between the reflective structure and the front side of the probe may be in the range of 70 to 100, preferably 75 to 95, more preferably 80 to 90, and most preferably 83 to 87. The reflective structure may include an imaging function.

[0058] The interaction region of the scanning probe microscope and the interaction region of the scanning particle microscope may at least partially overlap.

[0059] The imaging of the marker using the scanning particle microscope may be achieved by scanning the charged particle beam at a first frequency, where the first frequency is at least 5 times higher, preferably 10 times higher, more preferably 30 times higher, and most preferably 100 times higher than the vibration frequency of the probe. However, the first frequency may also be lower than the vibration frequency of the probe.

[0060] In addition, the device according to the invention may include a signal processing unit configured to use the stroboscopic effect to graphically capture even the high vibration frequency of the probe.

[0061] The probe may have an opening which is implemented such that a charged particle beam can pass through the opening and be directed onto the sample. Additionally, the opening of the probe may be implemented such that a charged particle beam can pass through the opening to scan the sample for imaging purposes.

[0062] The size of the opening is selected such that on the one hand, the scanning area of the charged particle beam does not have to be restricted. On the other hand, the width of the opening extending perpendicular to the longitudinal axis of the probe is specifically selected such that there is no risk to the mechanical stability of the probe.

[0063] The opening can have any form. Preferably, it is a symmetric opening, such as a circular, triangular, rectangular or square opening.

[0064] This configuration promotes a very good overlap between the interaction region of the probe with the sample and the interaction region of the charged particle beam with the sample. In particular, this configuration allows, for example, determining the position of particles present on the sample relative to the interaction region of the probe with the particles. This has great advantages when manipulating particles with the probe. Additionally, in this embodiment of the probe, it is possible to very quickly and simply switch between examining the sample and examining the probe by scanning the charged particle beam of a scanning particle microscope.

[0065] The probe may have a conductive embodiment for the purpose of shielding and / or compensating for the electrostatic charge of the sample.

[0066] If an electrically insulating sample (e.g., a lithography mask) is examined and / or processed using a charged particle beam, the sample can become electrostatically charged. Usually, a shielding device in the form of a closely meshed grid is applied to the output of the particle optical unit of a scanning particle microscope to shield the electrostatic charge of the sample, such as a lithography mask. If the probe of a scanning probe microscope is placed below the exit of a scanning particle microscope, there is no space for the shielding device of the scanning particle microscope. By means of the said probe of the scanning probe microscope having a conductive embodiment, the probe can at least partly additionally assume the function of a shielding element. In particular, this applies if the probe has an opening for the passage of a charged particle beam.

[0067] If it is determined that the sample has an electrostatic charge when the probe approaches the sample surface, the electrostatic charge of the sample can be compensated by applying a voltage to the conductive probe, such that a risk-free examination of the sample surface by the probe becomes possible even if the sample has an electrostatic charge.

[0068] The probe can be connected to a piezoelectric quad-morph piezoelectric actuator which is configured to deflect the probe.

[0069] Tubular piezoelectric actuators are typically used to position the probe of a scanning probe microscope on the surface of a sample. However, this embodiment of the piezoelectric actuator is disadvantageous for the scanning probe microscope of the device according to the invention, since in an optimal scenario, the exit of the charged particle beam of the scanning particle microscope is typically at a distance of a few millimeters from the surface of the sample. A piezoelectric actuator implemented in the form of a four-phase actuator element optimally utilizes the available limited space between the exit of the charged particle beam and the sample, without having to resort to mechanically unstable alternative solutions.

[0070] The device according to the invention may include a control unit configured to perform a coordinate transformation between the coordinate system of a lithography element and the coordinate system of the probe within a time interval < 50 μs, preferably < 10 μs, more preferably < 1 μs, and most preferably < 0.1 μs.

[0071] Scanning probe microscopes are typically constructed such that the coordinate system of the piezoelectric actuator is aligned with respect to the coordinate system of the sample or the sample stage on which the sample is disposed. However, this is generally not possible in the case of a combination of a scanning particle microscope and a scanning probe microscope, in the case of an in-situ configuration of the two microscopes, due to the aforementioned spatial limitations. The control unit of the device according to the invention is capable of performing the coordinate transformation in virtually real time (i.e., with minimal latency). This capability facilitates a rapid response of the device to deflections of the detected probe. Limitations in the throughput of the device according to the invention due to the device configuration can be largely avoided. The rapid coordinate transformation can be implemented in a control unit, such as in the form of an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit).

[0072] In addition, the control unit may be configured to perform the method steps of the method according to the invention.

[0073] In a second embodiment, a device for inspecting and / or processing a sample includes: (a) a scanning particle microscope for providing a charged particle beam that can be directed onto the surface of the sample; (b) a scanning probe microscope having a deflectable probe and an optical pointer system for detecting the deflection of the probe; (c) wherein the optical pointer system is at least partially guided in the column of the scanning particle microscope.

[0074] This embodiment of the device according to the invention allows for a very compact implementation of a combination of a scanning particle microscope and a scanning probe microscope, the interaction regions of which with the sample or the lithography element overlap. Despite the compact structure of the device according to the invention, the deflection of the probe of the scanning probe microscope can be detected by an optical pointer system that has proven its worth.

[0075] The scanning particle microscope can have at least one lens for the optical pointer system at the exit of its charged particle beam, the lens having an opening for the passage of the charged particle beam. The lens for the optical pointer system can be implemented as an annular lens.

[0076] The scanning particle microscope can include a window of the optical pointer system and a deflection mirror. The deflection mirror can deflect the optical radiation of the optical pointer system by substantially 90°. The deflection mirror can have an opening for the passage of the charged particle beam.

[0077] This allows a light source (which can be implemented by a laser, for example) and a photodetector (which can be implemented in the form of a quadrant photodiode, for example) to be arranged outside the scanning particle microscope.

[0078] The optical elements of the optical pointer system arranged in the scanning particle microscope can have a substantially optically transparent and conductive coating. The optically transparent and conductive coating can include an indium tin oxide (ITO) layer.

[0079] The conductive coating of the optical elements (i.e., the lenses and mirrors in the scanning particle microscope) can substantially prevent the electrostatic charging of the optical components due to scattered electrons.

[0080] The device according to the invention can include a light source, which is arranged outside the scanning particle microscope and implemented as a deflection probe, wherein the optical intensity of the light source is partially guided in the scanning particle microscope. The light source for the deflection probe can use the optical elements of the optical pointer system in the scanning particle microscope. The light source can include a laser system. The light source can use a wavelength range different from that of the light source of the optical pointer system.

[0081] The device according to the invention can have a compact structure, since the excitation of the deflection and the detection of the deflection use the same optical elements within the scanning particle microscope.

[0082] Furthermore, the device according to the invention can include at least one first container for storing at least one precursor gas and at least one second container for storing at least one etching gas. Furthermore, the device according to the invention can include at least one third container for storing additional gas. If necessary, the additional gas can be mixed with the precursor gas or the etching gas in order to assist the local deposition reaction on the sample and / or the probe, or in order to assist the local etching reaction on the sample and / or the probe.

[0083] In the case of the device according to the invention, the gases stored in the containers allow not only the inspection of the sample (such as a lithography mask and / or a wafer), but also the processing of the sample.

[0084] The device according to the invention can be configured to deposit a sacrificial tip on the probe of a scanning probe microscope. The sacrificial tip can be deposited on the probe of the scanning probe microscope by means of a charged particle beam of a scanning particle microscope and one or more precursor gases stored in a first container.

[0085] The charged particle beam can pass through the probe for the purpose of depositing the sacrificial tip. The scanning probe microscope can also be implemented to rotate the probe about its longitudinal axis.

[0086] The above device can also be implemented to attach the particles present on the sample to the probe. The particles can be attached to the probe by a deposition process induced by the charged particle beam on the precursor gas, by depositing material on the probe and / or the particles.

[0087] The charged particle beam can pass through the probe for the purpose of depositing the attachment material. In addition, the charged particle beam can be guided through an opening of the probe for the purpose of depositing the attachment material.

[0088] In addition, the device according to the invention can be implemented to separate the particles attached to the probe from the probe. The particles can be separated from the probe by performing a local EBIE (electron beam induced etching) process.

[0089] Even from points on the sample that are difficult to access, the particles can be reliably removed by attaching the particles to the probe of a scanning probe microscope. The cleaning process of the sample usually cannot reach the particles at points that are difficult to access.

[0090] The attachment material can form a connection between the probe and the particle, which connection is detachable or non-detachable to a limited extent.

[0091] If the attachment material forms a connection to a certain extent detachable between the probe or the sacrificial tip of the probe and the particle, this is advantageous. In this case, the probe can be used to continuously remove many particles. However, the attachment material can also achieve a non-detachable connection between the probe and the particle. In this case, a new probe is used to replace the probe loaded with particles.

[0092] The precursor gas for depositing the attachment material on the probe and / or the particles can include at least one element from the following group: ethylene (C2H4), styrene (C8H8), pyrene (C 16 H 10 ), hexadecane (C 16 H 34 ), liquid paraffin, formic acid (CH2O2), propionic acid (C3H6O2), and methyl methacrylate (C5H8O2).

[0093] It is advantageous if the connecting material has a large carbon component. The large carbon component of the connecting material promotes the simple separation of the particles to be removed from the sample from the probe of the scanning probe microscope. In addition, during the separation of the connection between the probe and the particle during the EBIE process, the connecting material mainly or at least partially comprising carbon forms volatile compounds which can be easily removed from the reaction zone of the local process.

[0094] The material for connecting the probe and the particle can be conductive. The precursor gas for depositing the conductive connecting material can include metal carbonyls. The metal carbonyls can include at least one element from the following group: chromium hexacarbonyl (Cr(CO)6), molybdenum hexacarbonyl (Mo(CO)6), tungsten hexacarbonyl (W(CO)6), dicobalt octacarbonyl (Co2(CO)8), dodecacarbonyltriruthenium (Ru3(CO) 12 ) and iron pentacarbonyl (Fe(CO)5).

[0095] The etching gas can include water vapor, hydrogen peroxide, xenon difluoride (XeF2), xenon dichloride (XeCl2), xenon tetrachloride (XeCl4), XNO, XNO2, XONO2, X2O, XO2, X2O2, X2O4 and X2O6 (where X is a halogen) and nitrosyl chloride (NOCl).

[0096] The probe can include a measurement tip for inspecting the sample. The device according to the invention can be implemented to deposit a sacrificial tip on the probe. In addition, the described device can be implemented to deposit a sacrificial tip on the measurement tip of the probe.

[0097] For the purpose of depositing a sacrificial tip on the probe, it is advantageous if the tip of the sacrificial tip and the charged particle beam are collinear. Therefore, it is advantageous if the probe is implemented to be rotatable about its longitudinal axis. Typically, the parameters of the charged particle beam must be adjusted for the purpose of depositing the sacrificial tip.

[0098] The length of the sacrificial tip can range from 50 nm to 10 μm, preferably from 100 nm to 5 μm, more preferably from 200 nm to 2 μm, and most preferably from 500 nm to 1 μm. The sacrificial tip can have a cylindrical form, the diameter of which ranges from 5 nm to 1000 nm, preferably from 10 nm to 500 nm, more preferably from 15 nm to 200 nm, and most preferably from 20 nm to 100 nm.

[0099] The sacrificial tip of the probe can be carbon-based. The precursor gas for depositing the sacrificial tip includes at least one element from the following: ethylene (C2H4), styrene (C8H8), pyrene (C 16 H 10 )、hexadecane (C 16 H34 ) Paraffin liquid, formic acid (CH2O2), propionic acid (C3H6O2) and methyl methacrylate (C5H8O2).

[0100] The sacrificial tip can be conductive. The precursor gas for depositing the conductive sacrificial tip can include metal carbonyls. The metal carbonyls can include at least one element from the following group: chromium hexacarbonyl (Cr(CO)6), molybdenum hexacarbonyl (Mo(CO)6), tungsten hexacarbonyl (W(CO)6), dicobalt octacarbonyl (Co2(CO)8), dodecacarbonyltriruthenium (Ru3(CO) 12 ) and iron pentacarbonyl (Fe(CO)5).

[0101] The probe can include a cantilever with a measurement tip and a fixed area, and the fixed area is attached to the end of the cantilever opposite to the measurement tip. The probe can be connected to the piezoelectric actuator of the scanning probe microscope through its fixed area.

[0102] The charged particle beam can include at least one element from the following group: electron beam and ion beam.

[0103] The electron beam for inspecting the sample substantially does not damage the sample, such as a lithography element. In addition, the advantages of the electron beam induced deposition process for depositing the sacrificial tip and / or for connecting the sacrificial tip to the particle are that the deposition reaction can be precisely positioned. In addition, by using the EBIE process to remove particles from the probe or from the sacrificial tip, low damage to the probe or the sacrificial tip can be maintained.

[0104] The diameter of the particle can be 5 nm to 10 μm, preferably 10 nm to 5 μm, more preferably 15 nm to 20 μm, and most preferably 20 nm to 1 μm.

[0105] The distance between the sacrificial tip of the probe positioned to receive the particle and the particle to be removed can be 0 nm to 2000 nm, preferably 0 nm to 500 nm, more preferably 0 nm to 100 nm and most preferably 0 nm to 50 nm.

[0106] The sample can include a lithography element. The lithography element can include at least one element from the following group: a lithography mask, a template for nanoimprint lithography, and a wafer. The lithography mask can include a reflective or transmissive mask. In addition, the lithography mask can include any mask type.

[0107] The device can include one or more displacement elements, which are implemented to perform relative movement between the probe and the sample in three spatial directions.

[0108] The device according to the present invention can include a modified scanning electron microscope and at least one atomic force microscope.

[0109] The device according to the invention may further comprise a detector for detecting X-ray radiation.

[0110] Particles can only be inspected to a very limited extent on a sample (e.g., a photomask). First, particles are usually located at points on the sample that are difficult to access. Second, in-situ analysis options are very limited because, of course, on the one hand, the analysis of the particles should not modify the surrounding area of the sample. On the other hand, the analysis of the particles should not falsify the sample around the particles. If the particles are removed from the sample by means of a cleaning process, the particles are usually lost in the analysis of the material composition of the particles.

[0111] In combination with a charged particle beam that excites the particles removed from the sample, the detector can be used to determine the material composition of the particles.

[0112] In one embodiment, a method of moving a particle on a sample comprises the steps of: (a) positioning a probe movable relative to a lithography element near the particle to be moved; (b) using a charged particle beam of a scanning particle microscope, an optical pointer system at least partially guided in the scanning particle microscope, or an optical pointer system comprising a reflective structure arranged on the probe, the reflective structure being arranged at an angle other than zero on the surface of the probe, for the purpose of determining the deflection of the probe during positioning; (c) moving the particle by moving the probe relative to the sample.

[0113] The charged particle beam of a scanning particle microscope can be used to inspect a sample. Then the probe of a scanning probe microscope should be used to move the particle identified by the charged particle beam. By moving, the particle should be detached from its anchoring or locking on the sample so that the particle can be removed from the sample during a cleaning process. By moving the probe, the particle can also be transported to a position on the sample where the particle does not impair the function of the sample (e.g., a lithography element). In the case of a photomask, this can be, for example, an inactive area of the photomask or an absorption pattern element.

[0114] The probe must be positioned on or near the particle in order to move the identified particle. Approaching the probe of a scanning probe microscope to the sample surface is a dangerous process because the sample and / or the probe may be damaged during this process. Therefore, this process must be monitored. Since a charged particle beam of a scanning particle microscope that discovers the particle is used here, an optical pointer system that at least partially guides optical radiation in the scanning particle microscope is used, or an optical pointer system having a reflective structure on the probe of a scanning probe microscope, the angle of the reflective structure relative to the probe surface is not zero, the method according to the invention requires, on the one hand, a minimum cost for aligning the probe relative to the identified particle and, on the other hand, facilitates the risk-free approach of the probe to the sample or particle to be moved. In addition, the use of the optical pointer system facilitates the determination of the force applied to the probe and thus the control of the probe.

[0115] The positioning of the probe relative to the sample may include determining the force acting between the probe and the sample.

[0116] By measuring the interaction between the probe and the sample, damage to the probe and / or the sample can be avoided when the probe approaches the surface of the sample.

[0117] The method according to the invention may also include the step of imaging the sample and / or the particles using a particle beam of a scanning particle microscope.

[0118] The described method may also include the step of switching between determining the deflection of the probe and imaging the sample.

[0119] A significant advantage of the described method is that the combination of a scanning particle microscope and a scanning probe microscope (whose interaction regions with the sample overlap) facilitates a rapid switch between the operating modes of the individual microscopes. Thus, in addition to the process of approaching the sample by the probe, the movement of the particles on the surface of the sample can be monitored. Therefore, the nature of the trial-and-error process can be at least partially removed from the movement of the particles on the sample.

[0120] The method according to the invention may also include the step of connecting the probe to the particle. Connecting the probe to the particle may include the step of depositing a material on the probe and / or the particle.

[0121] In addition to moving the particle by means of the probe of the scanning probe microscope, the particle can also be connected to the probe by depositing a material on or between the two elements. After a stable mechanical connection is created between the probe and the particle, the particle can be moved in a defined manner by effecting a relative movement between the probe and the sample. In particular, the particle can be removed from the sample.

[0122] The method according to the invention may also include the step of analyzing the particle by means of a charged particle beam and an energy dispersive detector for electromagnetic radiation. The charged particle beam can excite the particle, and the X-ray radiation originating from the particle can be analyzed by an energy dispersive X-ray radiation detector.

[0123] The advantage of connecting the probe to the particle is that the particle coupled to the probe can be supplied to examine its material composition, without being affected by the environment around the sample. Therefore, the origin(s) of the particle(s) can be determined at least in part. Thus, particle analysis represents an important step for removing the source(s) of the particle(s).

[0124] The described method may also include the step of removing the particle from the probe. Removing the particle from the probe may also include effecting a local etching process induced by a charged particle beam.

[0125] By removing particles from the probe, the particle-loaded probe does not need to be replaced but can be used to move or remove other particles.

[0126] Determining the deflection of the probe can include: positioning a charged particle beam on a detection area attached to the probe.

[0127] The described method may also include the step of setting the cross-sectional area of the charged particle beam such that the cross-sectional area of the beam is greater than 10 nm 2 and preferably 20 nm 2 and more preferably 50 nm 2 and most preferably greater than 100 nm 2 .

[0128] As already explained above, in a first exemplary embodiment of the method according to the invention, the charged particle beam is deliberately defocused with respect to the detection area attached to the probe, such that the spatial dependence of the charged particle beam-induced measurement signal of the probe is reduced. Furthermore, in this exemplary embodiment, the charged particle beam is not scanned over the probe; instead, it is set at a fixed position within the planar interaction area of the probe.

[0129] Determining the deflection of the probe can include: scanning a charged particle beam over the probe. In particular, determining the deflection of the probe can include: scanning a charged particle beam over an area of the probe having at least one marker.

[0130] The method according to the invention may also include the step of synchronizing the scanning of the charged particle beam over the probe with the vibration of the probe.

[0131] The described method may also include the step of performing a coordinate transformation between the coordinate system of the probe and the coordinate system of the sample within a time interval, the time interval being < 50 μs, preferably < 10 μs, more preferably < 1 μs, and most preferably < 0.1 μs.

[0132] The method according to the invention may also include the step of using an energy-dispersive X-ray radiation detector to detect X-ray radiation originating from the particles.

[0133] Finally, a computer program may include instructions that, when executed by a computer system, cause the device according to the above-described method steps to be performed according to the above-described method. 4. Description of the Drawings

[0134] Referring to the accompanying drawings, the following detailed description describes the presently preferred exemplary embodiments of the invention, in which:

[0135] Figure 1 A probe having a cantilever, a measurement tip, and a fixed area is schematically shown;

[0136] Figure 2 Schematically reproduces a cross-section of a first exemplary embodiment through a probe including a detection region and a detection structure;

[0137] Figure 3 Illustrates the secondary electron yield as a function of the angle between the excitation electron beam and the detector;

[0138] Figure 4 Illustrates a schematic cross-sectional view of a probe vibrating above a sample surface, where the probe in the upper part image has a detection region (diagram 450), and illustrates the extreme positions of the detection region during vibration of the probe in the upper part image and the associated secondary electron signal in the lower part image (diagram 490);

[0139] Figure 5 Reproduces the upper part image in the upper part image (diagram 550) Figure 4 of the upper part image, where the probe includes a second exemplary embodiment of a detection structure, and represents the extreme positions of the detection structure during vibration of the probe in the upper part image and the associated backscattered electrons in the lower part image (diagram 590);

[0140] Figure 6 Reproduces the secondary electron yield δ and the backscattering coefficient η as a function of the atomic number;

[0141] Figure 7 Schematically presents the time profile of the approach of the probe to the sample surface and the associated secondary electron signal;

[0142] Figure 8 Illustrates a schematic cross-sectional view of a probe passing over a sample, where the cantilever of the probe has a detection region and an opening for the passage of a charged particle beam;

[0143] Figure 9 Presents a schematic cross-sectional view of a probe passing over a sample, where the cantilever of the probe has a second embodiment of a detection structure and an opening for the passage of a charged particle beam;

[0144] Figure 10 Reproduces a schematic cross-sectional view of a probe with a curved detection region;

[0145] Figure 11 In the left part image, a schematic cross-sectional view of a probe is illustrated, the probe having another exemplary embodiment of a detection structure in the form of a marker, and in the right partial image, the lateral offset of the marker in the image of the probe in the case of probe deflection is illustrated;

[0146] Figure 12 Reproduces Figure 11, wherein the detection structure is implemented in the form of two markers having different heights;

[0147] Figure 13 Other exemplary embodiments of the detection structure in the form of two planar elements are specified in the lower part image, the two planar structures being arranged transversely with respect to the longitudinal axis at a distance from each other along the longitudinal axis of the probe, and a measurement signal in the case of a line scan of a charged particle beam above the two planar elements along the longitudinal axis of the probe is presented in the upper part image;

[0148] Figure 14 Reproduced when the measurement tip of the probe touches the surface of the probe Figure 13 ;

[0149] Figure 15 Side views and front views schematically illustrating various exemplary embodiments of the detection structure in the form of rectangular elements;

[0150] Figure 16 Side views and front views schematically illustrating other exemplary embodiments of the detection structure combined with various measurement tips of the probe;

[0151] Figure 17 A cross-sectional view illustrating a signal processing unit for a scanning particle microscope and its connection to a probe driver of a scanning probe microscope and its connection to a generator of a scanning signal of a charged particle beam of a scanning particle microscope;

[0152] Figure 18 Schematically illustrates a nanomanipulator, the coordinate system of which is rotated relative to the coordinate system of the sample stage;

[0153] Figure 19 Schematically illustrates the use of a quad-morph piezo-actuator for positioning and deflecting a probe between the exit of a coil of a scanning electron microscope and a sample;

[0154] Figure 20 Is a schematic cross-sectional view of a sacrificial tip, the sacrificial tip being attached to the measurement tip of the probe and positioned below the exit of the column of a scanning electron microscope near a particle present on a photomask;

[0155] Figure 21 Schematically illustrates the manner of connecting Figure 20 particles to the sacrificial tip by performing a local deposition process;

[0156] Figure 22 Schematically illustrates the process of removing particles connected to the sacrificial tip from a photomask;

[0157] Figure 23Schematically reproduces the manner in which particles are separated from a sacrificial tip by implementing a local etching process;

[0158] Figure 24 Illustrates a cross-sectional view of a combination of a scanning electron microscope and an atomic force microscope;

[0159] Figure 25 Shows a cross-sectional view through a combination of a scanning electron microscope and an atomic force microscope, in which radiation of an optical pointer system for detecting the deflection of a probe of the atomic force microscope is partially guided in the column of the scanning electron microscope;

[0160] Figure 26 Presents a schematic cross-sectional view through a combination of a scanning particle microscope, a scanning probe microscope, and an optical pointer system, wherein the optical pointer system has a reflective structure arranged on the probe, and the reflective structure is arranged on the probe of the scanning probe microscope at an angle different from zero;

[0161] Figure 27 Presents a cross-sectional view through a combination of a scanning electron microscope and a nanomanipulator, which is arranged in the column of the scanning electron microscope in a manner rotated with respect to the sample normal;

[0162] Figure 28 Reproduces the use of Figures 24 to 26 a flowchart of the processing process of a sample in one of the devices; and

[0163] Figure 29 Illustrates a flowchart of a method according to the invention; 5. DETAILED DESCRIPTION

[0164] The currently preferred embodiments of the device according to the invention and the method according to the invention for inspecting and / or processing a sample are explained in more detail below using the example of a lithography mask. However, the use of the device according to the invention and the method according to the invention is not limited to the examples discussed below. Rather, these can generally be used for inspecting and / or processing lithography elements. In particular, the devices and methods described in this application can be used for analyzing and / or modifying highly sensitive samples having structures in the nanometer range. As an example, the device according to the invention and the method according to the invention can be used for inspecting and / or modifying biological samples.

[0165] Figure 1Schematically presents an example of a probe 100 for a scanning probe microscope. The exemplary probe 100 includes a bent beam 110 or a lever arm 110. Hereafter, the bent beam 110 - as is customary in the art - is referred to as a cantilever 110. The cantilever 110 of the probe 100 has a measurement tip 120 at one end (the free end). The measurement tip 120 is applied to the dorsal side 125 of the cantilever 110 of the probe 100. Below, the side opposite to the measurement tip 120 is referred to as the front side 115 or the top side 115 of the probe 100. In Figure 1 the example, the measurement tip 120 includes an elongated thin tip with a small radius of curvature, which is implemented to analyze the surface of a sample, such as a mask or a wafer. At the opposite end or the free end to the measurement tip 120, the cantilever 110 of the probe 100 has a fixed region 130. By means of the fixed region 130, the probe 100 can be connected to a piezoelectric actuator, which is incorporated into the measurement head of a scanning probe microscope ( Figure 1 not shown in the figure).

[0166] The cantilever 110 of the probe 100 can be moved by the movement of the fixed region 130. In particular, the cantilever 110 can be excited to vibrate. For this purpose, as already described above, the fixed region 130 of the probe 100 can be connected to a piezoelectric actuator, which can excite the cantilever 110 to vibrate, for example, at the resonance frequency of the probe 100 (not reproduced in Figure 1 the figure) or near the resonance frequency. The vibration mode of the cantilever 110 can be used during the approach of the measurement tip 120 to the surface of the sample and / or for sensing the sample in the area of the particle.

[0167] Below, the term "sample" includes an element having structural elements with dimensions in the micrometer and / or nanometer range on at least one of its surfaces. The structural elements include the intended structures and the structural elements that should not be present on the sample, such as particles. In particular, the sample can include a lithographic element. The lithographic element includes a template for a lithographic mask, a wafer, and / or nanoimprint technology.

[0168] The cantilever 110 can have a bimorphic structure, i.e., include two interconnected layers stacked on top of each other, and the layers exhibit different thermal expansion properties ( Figure 1 not shown in the figure). Depending on the embodiment, due to the deposition of energy into the cantilever, the cantilever 110 can bend towards or away from the surface of the sample. As an example, energy can be locally introduced into the cantilever 110 by using the radiation of a laser beam. In addition, a resistor can also be attached to the cantilever 110 in order to bend the latter towards or away from the surface of the sample by local heating ( Figure 1 not shown in the figure).

[0169] As already explained above, the probe 100 can be connected through the fixed region 130 (inFigure 1 is connected to an actuator, for example in the form of a piezoelectric actuator. The piezoelectric actuator can deflect the cantilever 110 of the probe 100. In particular, the piezoelectric actuator can move the measurement tip 120 in the direction of the sample surface. In addition, the piezoelectric actuator can excite the cantilever 110 of the probe 100 to vibrate. Preferably, the piezoelectric actuator excites the cantilever 110 at or near the resonance frequency of the probe 100. The cantilever 110 can include a resistive element for bending the cantilever 110 towards or away from the surface of the mask. In addition, an additional light source for deflecting the probe 100 can be used, and the light beam of the light source is partially guided in the scanning particle microscope.

[0170] In addition, the cantilever 110 can be deflected due to electrostatic forces and / or based on the inverse piezoelectric effect. In addition, a magnetic field (magnetostriction) can be used to move the cantilever 110 towards or away from the sample surface.

[0171] The surface of the cantilever 110 of the probe 100 opposite to the measurement tip 120 can be provided with a thin metal reflection layer in order to increase the reflectivity of the surface of the cantilever 110 for the light beam used as an optical pointer ( Figure 1 not shown in the figure).

[0172] In the upper partial image, Figure 2 a schematic cross-sectional view through a probe 200 having a cantilever 110 and a measurement tip 220 is shown, and the measurement tip 220 has been tilted relative to the measurement tip 120 of the probe 100. The charged particle beam can sense the tip 225 of the measurement tip 220 through this arrangement of the measurement tip 220. In particular, the charged particle beam can determine the contact between the measurement tip 220 and the sample surface and / or the distance from the particles present on the sample surface.

[0173] A detection structure 230 in the form of a detection area 230 is attached to the front side 115 of the probe 200, which is opposite to the back side 125 on which the measurement tip 120 is arranged. In Figure 2 the illustrated example, the angle of the detection area 230 relative to the front side surface 115 of the probe 200 is approximately 40°, and the front side is opposite to the back side surface 125 of the probe 200 having the measurement tip 120. In an alternative exemplary embodiment, the angle range of the detection area 230 relative to the front side surface 115 of the probe 200 is 80° to 88°.

[0174] The probe 200 and the detection area 230 can have a complete embodiment. However, it is advantageous to manufacture the detection area 230 from a material whose emission ability is optimized for secondary charged particles in the forward direction. Suitable for this purpose are materials whose atoms have a high atomic number, such as tungsten, osmium, indium, platinum or gold.

[0175] Figure 2 Diagram 250 shows, in an enlarged manner, the incidence of the charged particle beam 240 on the detection region 230 of the probe 200. The charged particle beam 240 may include an electron beam and / or an ion beam. Without loss of generality, for the sake of simplicity, in the following observations, the charged particle beam 240 is restricted to the electron beam 240, and the secondary charged particles 260 are restricted to the secondary electrons 260. For an ion beam incident on the detection region 230, the following observations can be made similarly.

[0176] The electron beam 240 generates secondary electrons due to the interaction with the material of the detection region 230. The secondary electrons include scattered or backscattered electrons and secondary electrons (SE). The generated secondary electrons have a broad energy spectrum. Generally, the spectrum of the secondary electrons has peaks in the region of several electron volts (eV), followed by a broad background. Due to energy conservation, the maximum energy of the secondary electrons is limited by the kinetic energy of the electron beam 240 incident on the detection region 230.

[0177] Secondary electrons refer to all secondary electrons with a kinetic energy < 50 eV after leaving the detection region. Their most probable energy lies in the energy range of 2 to 5 eV. Due to their low kinetic energy and thus low range in the material of the detection region 230, SEs originate from a thin surface layer of the detection region 230, the thickness of which is 5 nm to 50 nm. SEs are generated by the inelastic interaction of the electron beam 240 with the atomic shells of the material of the detection region 230.

[0178] The generated secondary electrons with a greater kinetic energy are called backscattered secondary electrons (BSE) or simply backscattered electrons (BE). The broad spectrum of BSEs is related to the electrons of the electron beam 240, which have lost some of their kinetic energy due to many scattering processes in the material of the detection region 230. The diameter of the exit surface from the detection region 230 and the penetration depth of the BSEs depend on the material of the detection region 230 and the energy of the electron beam 240. The order of magnitude of both is in the micrometer range.

[0179] The following considerations are related to SEs, i.e., secondary electrons with a kinetic energy < 50 eV. As Figure 2 illustrated by diagram 250, SEs can be emitted by the detection region 230 in the forward direction and the backward direction. If the SE 260 is emitted from the surface of the detection region 230 on which the main charged particle beam 240 is incident, the SE 260 leaves the detection region 230 in the forward direction. Conversely, if the SE 270 is emitted from the surface of the detection region 230 opposite to the incident region of the main charged particle beam 240, the SE 270 leaves the detection region 230 in the backward direction.

[0180] The material composition of the detection region 230 is selected such that the emission rate of secondary electrons (SE) 260 emitted in the forward direction is maximized and the emission rate of secondary electrons 270 emitted in the backward direction is minimized. To this end, it is advantageous to select a material with a high atomic number for the detection region 230.

[0181] The secondary electron yield or SE yield δ is defined as the quotient of the number of secondary electrons emitted and the number of primary electrons of the electron beam 240. The dependence of the SE yield on the angle of incidence on the detection region is approximately described by the following formula (see A.G. Libinson: "Tilt dependence of the secondary electron emission at low excitation", Scanning, Vol. 21, pp. 23 - 26, 1998):

[0182]

[0183] where δ SE (0) represents the SE yield of an electron beam incident perpendicularly on the sample, θ represents the rotation angle of the sample relative to the horizontal orientation, i.e., θ = 90° describes the grazing incidence of the electron beam on the sample, and η represents the coefficient of dependence on material and energy, which typically ranges from 0.8 to 1.2.

[0184] With the aid of the specified formula, the material composition, material strength or material thickness, and the orientation of the detection region 230 relative to the incident electron beam 240 can be optimized such that for a predetermined electron energy of the charged particle beam 240, a low-noise and low-distortion SE signal of the SE 260 emitted in the forward direction is obtained from the detection region 230. Figure 2 The upper diagram in schematically illustrates the trajectory of the SE 260 emitted by the detection region 230 in the forward direction. The SE 260 is incident on the incident opening 280 of the detection system 290 or the detector 290, which is designed to detect secondary electrons 270. As an example, the detector 290 can be a combination of a scintillation counter and a photomultiplier, for example, in the form of an Everhart-Thornley detector.

[0185] In Figure 2 The configuration of the electron beam 240, detector, SE 260, and detector schematically illustrated in includes the SE detector 290. Two or more SE detectors 290 can also be used to detect the SE 260.

[0186] Figure 3 The diagram 300 in shows the SE signal intensity as a function of the angle between the incident electron beam 240 and the detection region 230. As withFigure 2 As shown differently, in this exemplary embodiment, the detection region 230 is substantially perpendicular to the plane of the probe 200 or the beam axis of the incident electron beam 240, and the detection region has only a small angle of less than 10°. Since the suction voltage is applied to the detection system 290, almost all secondary electrons are recorded by the detection system 290. In Figure 3 the example shown, the grazing incidence of the electron beam 240 is selected to optimize the angular dependence of the SE yield. As is evident from the formula specified above, as expected, within the specified small angle range, the SE yield δ increases slightly more strongly than linearly.

[0187] Figure 4 The upper part image or diagram 450 of Figure 2 shows the probe 200 that vibrates above the sample 400 (e.g., the lithography element 400). The vibration of the probe 200 is represented by the bidirectional arrow 410. The probe 200 vibrates about an axis perpendicular to the plane of the paper. Figure 4 A snapshot of the diagram 450 in Figure 1 shows the probe 200 or its measurement tip 220 when it is closest to the sample 400. In

[0188] Figure 4 the lower part image or diagram 490 in Figure 2 clarifies the orientation of the detection region 230 of the probe 200 at two extreme points (i.e., the reverse points of the moving direction of the measurement tip 220 of the probe 200). In the arrangement of the detection region 230 represented by the bidirectional arrow 460, the detection region 230 has substantially the same alignment as the Figure 4 probe 200 in

[0189] Due to the angular dependence of the SE yield, the SE yield is high in this configuration. As specified by the diagram 490 in Figure 4 the SE signal of the SE detector 290 has a maximum value.

[0189] In the arrangement shown above the bidirectional arrow 470, due to the deflection of the probe 200, the detection region 230 has been substantially rotated to the horizontal direction. Due to the angular dependence of the SE yield, the SE yield is low at this position of the detection region 230. Therefore, the number of secondary electrons recorded by the detection system is much lower than the number of secondary electrons in the configuration explained above.

[0190] Figure 5 The diagram 550 in the upper part image of Figure 4 schematically presents a second exemplary embodiment of the probe 500 with the detection structure 530. As in Figure 4 the probe 500 vibrates above the sample 400. This is again clarified by the bidirectional arrow 410. In Figure 5In the illustrated example, the detection structure 530 includes a rectangular structure 530 having two layers, the materials of which have different numbers of atoms.

[0191] First, Figure 6 the secondary electron yield δ as a function of the number of atoms or the number of protons is presented. The measured data of the SE yield δ are from D.B. Wittry: page 185 of "Optique des rayons X et microanalyse" (edited by R. Castaing, P. Deschamps, J. Philibert) published by Hermann in Paris in 1966. Second, Figure 6 the backscattering coefficient η of the backscattered electrons as a function of the number of atoms is reproduced. The measured data of the backscattering coefficient η have been taken from the following literature: "X-Ray Optics and Microanalysis" by K.F.J. Heinrich on page 1509 of the "Proceedings of the 4th International Congress on X-Ray Optics and Microanalysis (Proc. 4th Internat. Congress on X-Ray Optics and Microanalysis)" (edited by R. Castaing, P. Deschamps, and J. Philibert) held in Paris by Hermann in 1966. The SE yield δ and the coefficient of the backscattered electrons (BSE) vary as a function of the number of atoms. Preferably, materials with as different numbers of atoms as possible are used for the detection structure 530 for the purpose of determining the deflection of the probe 500. As an example, the quotient of the backscattering coefficients is significantly greater than five for the combination of the detection structure 530 made of carbon (Z = 6) with one of the following metals: tantalum (Z = 73), tungsten (Z = 74), rhenium (Z = 75), osmium (Z = 76), indium (Z = 77), platinum (Z = 78), and gold (Z = 79).

[0192] Return to reference Figure 5 In the diagram 500 of, the electron beam 240 is directed onto the layer of the detection structure 530. The electrons of the electron beam 240 emitted by the detection structure 530 are illustrated by the arrow 560. In Figure 5 the snapshot illustrated in, the probe 500 or its measurement tip 220 is closest to the sample 400. The electron beam 240 is directed onto the layer 533 of the detection structure 530 having a low number of atoms or protons. Within the range of one vibration period, the electron beam 240 passes twice over the detection structure 530 and is directed onto the layer 536 of the detection structure 530 having a high number of atoms at the reversal point when the distance between the probe 500 and the sample 400 is maximum.

[0193] Figure 5The lower part of the image or diagram 590 therein shows the incidence of the electron beam on the detection structure 530 of the probe 500 at two extreme points (i.e., the reverse points of the moving direction of the measurement tip 220 of the probe 500). In the configuration between the electron beam 240 and the detection structure 530 represented by the double-headed arrow 560, the electron beam 240 is incident on the layer 536 with a high atomic number of the detection structure 530, and the BSE signal caused by the emitted electrons 560 of the electron beam 240 has a maximum value. As explained in the context of the diagram 550 in Figure 5 at this time, the measurement tip 120 of the probe 500 has the maximum distance from the sample 400.

[0194] When illustrated by the double-headed arrow 570, the electron beam 240 is directed onto the layer 533 of the detection structure 530, and the material of this layer 533 has a low atomic number. The backscattering coefficient η of the electrons 560 of the electron beam emitted by the layer 533 is small, and the BSE detector only registers a low signal. At this time, the distance between the measurement tip 220 of the probe 500 and the sample 400 is the smallest.

[0195] Figure 7 The diagram 700 in Figure 2 schematically shows the process of the probes 200, 500 approaching the sample 400, and this approach is monitored by: irradiating the detection area 230 or the detection structure 530 with the electron beam 240 and detecting the secondary electrons 260 using the detector 290 (as explained in the context of Figure 7 ), or by detecting the backscattered or emitted electrons 560. For clarity, the detection area 230 or the detection structure 530 and the electron beam 240 have been suppressed in the diagrams 720, 740, and 760 of

[0196] The diagram 720 represents the free oscillation of the probes 200, 500. The unobstructed vibration of the probes 200, 500 is represented by the double-headed arrow 710 in the diagram 720. The solid line 770 presents the time curve of the average distance of the measurement tip 220 of the probes 200, 500 from the surface of the sample 400. The curve or vibration 780 shows the SE signal 480 of the detector 290 or the BSE signal 580 of the backscattered electrons 560 as a function of time. Generally, the frequency of the unobstructed vibration of the probes 200, 500 is in the range of 10 Hz to 10 MHz. In the example illustrated in Figure 7 the vibration frequency is 45 kHz. Typically, the free vibration amplitude of the probe is in the range of 5 nm to 5 μm. In the example of Figure 7 the vibration amplitude is approximately 200 nm.

[0197] Figure 7The diagram 740 therein presents a configuration in which the average distance between the measurement tip 120 and the sample 400 decreases linearly, i.e., the probes 200, 500 descend onto the sample 400. During each vibration cycle, as long as the vibration amplitude of the probes 200, 500 becomes smaller than the average distance 770 by a factor of two, the probes 200, 500 start to land on the surface of the sample 400. The time portion during the vibration cycle when the measurement tip 220 is in contact with the sample 400 increases as the average distance between the measurement tip 220 of the probes 200, 500 and the surface of the sample 400 vanishes. As long as the measurement tip 120 is in contact with the sample 400 during vibration, the amplitude of the curve 780 starts to decrease. If the measurement tip 220 of the probes 200, 500 no longer lifts from the surface of the sample 400, the SE signal 480 or the BSE signal 580 vanishes because the angular dependence of the SE yield no longer substantially changes and thus the secondary electrons 260 detected per unit time no longer change.

[0198] Finally, Figure 7 the diagram 760 therein illustrates the state where the measurement tip 120 of the probes 200, 500 no longer lifts from the surface of the sample 400.

[0199] Figure 8 A cross-sectional view through a probe 800 having a cantilever 810 and a measurement tip 220 is schematically shown, as in Figure 2 , 4 , 5, and 7, the measurement tip is inclined away from the fixed region 130 of the probe 800 and points. The cantilever 810 of the probe 800 has a detection region 230. In addition, the cantilever 810 of the probe 800 has an opening 820 through which the electron beam 840 can pass to scan or service the surface 830 of the sample 400 in the region of the tip 650 of the measurement tip 120. Different from that described in the previous exemplary embodiments, a focused electron beam 840 is used to scan the sample surface 830. For detecting the SE 260 and backscattered electrons (BSE) 560 emitted by the sample 400, a detector 290 or a second detector ( Figure 8 not shown in

[0200] The sample 400 (e.g., a photolithography mask 400) can be electrically insulating or at least include electrically insulating regions. The electrically insulating regions can be electrostatically charged during irradiation with a charged particle beam (e.g., an electron beam 840). As a result, image distortion is generated by the electron beam 840. Since the measurement tip 220 of the probe 800 and the detection region 230 are not applied to the free end of the cantilever 810, but instead the cantilever 810 has an opening 820 in the region of the tip 830 of the measurement tip 220, the cantilever 810 of the probe 800 can largely shield the electrostatic charging of the sample surface 830 and thus avoid imaging distortion of the sample 400. In order for the probe 800 to be able to function as an electrical shielding element, the cantilever 810 of the probe 800 must have a conductive embodiment.

[0201] If the cantilever 810 is additionally designed such that a voltage can be applied to it, this can be used to inspect the electrostatically charged sample 400 using the probe 800 of a scanning probe microscope. By applying a voltage to the cantilever 810 of the probe 800, the electrostatic charging of the sample 400 can be largely compensated. This promotes risk-free sensing of the sample 500 by the probe 800. Without compensating for the electrostatic charging of the sample 400, an arc may occur between the tip 830 of the measurement tip 120 and the sample 400, and thus the measurement tip 120 and / or the sample 400 may be damaged or even irreparably damaged.

[0202] Figure 9 is reproduced Figure 8 , where the only difference is that the probe 900 has a detection structure 530 instead of a detection region 230. The functions of the probes 800 and 900 are coupled to their positioning and that of the measurement tip 220, and are independent of the detection structures 230, 530 used to detect the deflection of the probes 800 and 900. Thus, the explanation regarding Figure 8 also applies to Figure 9 .

[0203] Figure 10 The probe 1000 is reproduced, which has a third exemplary embodiment of a detection structure in the form of a curved detection region 1030. As represented by equation (1), the SE yield δ(θ) strongly nonlinearly depends on the angle θ at which the electron beam 240 is incident on the detection region 230 of the probe 200. Although the signal of the secondary electrons 260 is nonlinear, the movement of the probe 200 can be adjusted in the z direction (i.e., in the vertical direction) in a closed control loop.

[0204] To simplify the closed-loop control of the z movement of the probe 200, the detection structure can be bent such that although the probe 200 deflects or vibrates, the electron beam 1040 always impinges on the bent detection region 1030 at the same angle or at an approximately same angle. This means that the curvature of the detection region 1030 reproduces the trajectory of the deflection of the probe 1000 in the incident region of the electron beam 240. Thus, since the angular dependence of the SE yield is largely compensated, a practically linear relationship is created between the deflection of the probe 1000 and the SE signal measured by the detector 290. However, due to the detection structure implemented in the form of the bent detection region 1030, the translational invariance of the incident electron beam 1040 above the bent detection region 1030 in the longitudinal direction of the probe 1000 must be abandoned.

[0205] Figure 11 Illustrates another exemplary embodiment of a detection structure that enables the detection of the deflection of a probe 1100 of a scanning probe microscope by means of an electron beam 1140, typically by means of a charged particle beam 1140. In Figure 11 the illustrated example, the detection structure 1130 has a marker 1130 in the form of a tip that is applied to a surface opposite the measurement tip 120 of the cantilever 110 of the probe 1100. In Figure 11 the example, the marker 1130 is fixed from the free end 1160 of the cantilever 110 of the probe 1100 at substantially the same distance as the measurement tip 120. However, this is not a prerequisite for the function of the marker 1130. However, it is advantageous to attach the marker 1130 near the free end 1160 of the cantilever 110 because this maximizes the change in the detected marker 1130 when deflecting the cantilever 110 of the probe 1100. To maximize the contrast of the image of the marker 1130 generated by the electron beam 1140, it is advantageous if the material used for the marker 1130 is different from the material of the cantilever 110 of the probe 1100.

[0206] Figure 11 The right partial image in shows schematically the lateral displacement 1150 of the marker 1130 of the probe 1100 due to the deflection of the probe 1100. During imaging using the electron beam 1140, the deflection of the probe 1100 can be determined from the lateral displacement 1150 of the marker 1130. Different from using the detection regions 230, 1030 to determine the deflection, the electron beam 1140 is preferably guided in a focused manner over the region of the probe 1100 having the marker 1130 for the purpose of imaging the marker 1130 by a scanning electron microscope.

[0207] Figure 12Shows a probe 1200 having a detection structure 1230 in the form of two markers 1240 and 1260. The two markers 1240 and 1260 are again implemented in the form of tips, but the tips have different heights. In Figure 12 In the example of, the markers 1240 and 1260 are attached along a line on the probe 1200, the line being perpendicular to the longitudinal axis of the probe 1200. Although this arrangement is not a prerequisite for the functionality of the markers 1240 and 1260, it simplifies the evaluation of the measurement of the signal in the case of lateral displacement of the markers 1240 and 1260 caused by deflection of the probe 1200 during imaging by the electron beam 1140.

[0208] Figure 12 The right partial image of reproduces the lateral displacement 1250 of the two markers 1240 and 1260 of different heights. Compared with Figure 11 the exemplary embodiment in which there is only one marker 1130, the probe 1200 having two markers 1240 and 1260 allows different measurements to be carried out for the purpose of determining the deflection of the probe 1200 in the images of the two markers 1240 and 1260. Compared with Figure 11 the probe 1100 in, this improves the measurement accuracy of determining the deflection of the probe 1200.

[0209] Figure 13 Reproduces another exemplary embodiment of a detection structure 1330 which enables the deflection of a probe 1300 of a scanning probe microscope to be detected by means of an electron beam, generally by means of a charged particle beam. Just like the subsequent Figure 14 As, Figure 13 the electron beam is not shown. In Figure 13 the example specified in, the detection structure 1330 has two rectangular elements 1340 and 1360 which are applied to the surface 115 or the top side 115 opposite the measurement tip 220 of the cantilever 110 of the probe 1300. The rectangular elements 1340, 1360 extend over a major part of the width of the probe 1300. The surface normals of the rectangular elements 1340, 1360 are substantially parallel to the longitudinal axis of the probe 1300 or the cantilever 110. In Figure 13 the example of, the two rectangular elements 1340, 1360 have different heights. However, this property is not essential for their function as the detection structure 1330. In addition, elements 1340 and 1360 having any thin or lamellar structure can be used to produce the detection structure 1330.

[0210] Preferably, the material composition of the generally rectangular and sheet-like elements 1340, 1360 is different from that of the cantilever 110 or its surface. Thus, in addition to the topological contrast, the electrons of the electron beam additionally generate a material contrast. Materials with a high atomic number are preferably used for the rectangular or sheet-like elements 1340, 1360. This applies if backscattered electrons are used to detect the detection structure 1330 in the form of the elements 1340 and 1360. However, the rectangular or sheet-like elements 1340, 1360 can also be maximally generated by depositing carbon. In this embodiment, secondary electrons can be used to detect the detection structure 1330 in the form of the elements 1340 and 1360. A line scan of the electron beam or charged particle beam in the direction of the longitudinal axis of the probe 1300 is sufficient to detect both elements 1340 and 1360.

[0211] Figure 13 The upper part of the image in shows the measurement signal in the case of a line scan over the two elements 1340, 1360 of the detection structure 1330. As already explained above, secondary electrons 260 and / or backscattered electrons 560 can be used to detect the detection structure 1330. The curve 1380 of the measurement signal shows peaks in each case when the electron beam senses the elements 1340 and 1360 of the detection structure 1330 during the line scan. In Figure 13 the upper part of the image in, the two peaks have substantially the same height because the material compositions of the rectangular or sheet-like elements 1340 and 1360 are substantially the same. However, this is not a prerequisite for the function of the detection structure 1330. Instead, the two elements 1340 and 1360 of the detection structure 1330 can be made of different materials.

[0212] Figure 13 The lower part of the image in shows a snapshot of the vibrating probe 1300 during its zero crossing. Figure 14 reproduces the situation when the measurement tip 120 of the probe 1300 is closest to the sample 400 Figure 13 . In most operating modes of the scanning probe microscope, at this time, the measurement tip 120 is in mechanical contact with the surface 650 of the probe 400. Due to the curvature of the probe 1300 or its cantilever 110, the apparent spacing between the two elements 1340 and 1360 detected by a line scan of the electron beam in the longitudinal direction of the cantilever 110 is less than Figure 13 the situation in. Thus, the detection structure 1330 allows the detection of the deflection of the probe 1300 and thus allows the inspection and / or processing of the sample 400 using the probe 1300 of the scanning probe microscope. The advantage of the detection structure 1330 is that no reference measurement is required due to the two rectangular or sheet-like elements 1340 and 1360.

[0213] Figure 15The two lower left part images 1505 therein show side views of the probes 500 and 1300 that have been discussed. The two lower right part images 1555 reproduce front views of the probes 500 and 1300. In addition, the upper left part image 1505 presents a side view of the probe 1500, while the upper right part image 1555 presents a front view of the probe 1500 with the detection structure 1530 on the front side surface 115 of the probe 1500. The detection structure 1530 has a rectangular element that extends over most of the width of the probe 1500. The rectangular element of the detection structure 1530 tapers gradually towards the top. As has been Figure 13 explained in the context of, it is advantageous if there is a difference in the material composition of the detection structure 1530 of the probe 1500 and the material composition of the cantilever 110 of the probe 1500. Different from Figure 13 the detection structure 1330 in, Figure 15 the detection structure 1530 in the form of a single rectangular element in requires a reference measurement in order to detect the deflection of the probe 1500 from the displacement of the peak of the measurement signal of the SE and / or BSE electrons caused by the detection structure 1530.

[0214] Figure 16 illustrates other exemplary embodiments of the detection structures 1630 and 1690. Similar to Figure 15 that, the left part image 1605 presents a side view, and the right part image 1655 provides front views of the probes 1600, 1640, and 1670. In the case of the probe 1600 in the upper part image, different from the measurement tip 220, the measurement tip 150 points to the holding plate 130 of the probe 1600. The rectangular detection structure 1630 is applied to the same surface 125 as the measurement tip 150. Compared with the previously discussed embodiments of the probes 200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, this configuration simplifies the manufacture of the probe 1600. Since the detection structure 1630 is placed at an angle, a line scan in the longitudinal direction of the probe 1600 produces a wide maximum of the measurement signal of the secondary electrons and / or backscattered electrons. The width of the measurement signal varies periodically with the vibration frequency of the probe 1600.

[0215] In the configurations reproduced in the central portion images 1605 and 1655, the detection structure 1630 reproduced in the upper portion image is deposited on the cantilever 110 of the probe 1640. Then, the measurement tip 170 for the probe 1640 is deposited on the detection structure 1630. Different from the measurement tips 220 and 150, the measurement tip 170 stands substantially vertically on the dorsal surface 125 of the cantilever 110 of the probe 1640. Similar to the probe 1600, the measurement tip 170 and the detection structure 1630 are attached to the lower side 125 of the cantilever 110 of the probe 1640 for the probe 1640, thus simplifying the manufacture of the probe 1640. In addition, the configuration of the probe 1640 is advantageous because the lower side 125 of the cantilever 110 has a larger distance from the surface 650 of the sample 400.

[0216] Figure 16 The lower portion images 1605 and 1655 in again present an exemplary embodiment of the probe 1670, where the measurement tip 120 is attached to the dorsal side 125 of the cantilever 110 of the probe 1670. The cantilever 110 of the probe 1670 has a rod-shaped detection structure 1690 on the front side 115. Instead of the rod-shaped detection structure 1690, the probe 1670 can have a detection structure implemented in other forms. As an example, the detection structure 1690 can be implemented in the form of a cylinder or in the form of a cone ( Figure 16 not shown in). In addition, the detection structure 1690 can be implemented with any profile. Different from the detection structure 1630, the detection structure 1690 is imaged above the front side 115 of the cantilever 110 of the probe 1670 by planar scanning.

[0217] Figure 17 The diagram 1700 in schematically shows a cross-sectional view through a device that can be used to measure the excitation of the vibrations of the probes 800, 900, 1670 during the scanning process. The core of the device is the signal processing unit 1750. Via the connection 1765, the latter receives the measurement data of the scanning electron microscope 1710. The signal processing unit 1750 slows down the measurement data of the scanning electron microscope 1710 by means of equivalent time sampling (ETS). This means that the measurement signals of the probes 800, 900, 1670 are recorded at a much lower frequency than the vibration frequencies of the probes 800, 900, 1670. For this purpose, the signal processing unit 1750 has a gated integrator and / or a boxcar averager.

[0218] The probe driver 1720 excites the probes 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670 to vibrate via the connection 1715. In Figure 17In the example illustrated in the figure, this is the probe 1200. The probe driver 1720 forwards the excitation frequency via the connection 1725 to the delay unit 1730. The delay unit 1730 forwards the trigger signal via the connection 1735 to the deflection generator 1740, which controls the scanning 1780 of the electron beam 1140 over the markers 1240, 1260 in the detection structure 1230 via the connection 1745.

[0219] Typically, a scanning probe microscope is constructed such that the coordinate system of the piezoelectric actuator and the coordinate system of the sample stage 1110 are aligned with respect to each other. However, due to the spatial limitations when a scanning particle microscope is combined with a scanning probe microscope or a nano-manipulator, this is typically not possible. Figure 18 The illustration 1800 in shows a sample stage 1810 having a support 1820 for holding the sample 400. The coordinate system of the sample stage 1810 is denoted by the reference numeral 1830. The sample 400 is processed by the tip 1850 of the processing head 1860 of the nano-manipulator 1840. Due to Figure 18 the space restricted by a scanning particle microscope not illustrated in, the coordinate system 1870 of the nano-manipulator 1840 is rotated with respect to the coordinate system 1830 of the sample stage 1810. To perform a fast coordinate transformation between the two coordinate systems 1830 and 1870, the control unit of the nano-manipulator 1840 can be equipped with an ASIC (application-specific integrated circuit), for example, which can perform the coordinate transformation between the coordinate systems 1830 and 1870 in less than 10 μs. In an alternative embodiment, the coordinate transformation between the coordinate systems 1830 and 1870 can be performed by analog electronics. In both embodiments, the transformation time for the coordinate transformation is short enough so as not to delay or substantially not delay the control signal of the probe operating in a closed control loop.

[0220] Figure 19 shows other options for utilizing the limited amount of space in the case where a scanning particle microscope and a scanning probe microscope are combined to the maximum possible extent. Typically, the probes 100, 200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670 of a scanning probe microscope are positioned by means of a tubular piezoelectric actuator. As an example, Figure 18 the processing head 1860 of the nano-manipulator 1840 in also has a tubular piezoelectric actuator. However, if these instruments are combined with a scanning probe microscope, the shape of the tube is disadvantageous for use in the nano-manipulator 1840 or the scanning probe microscope. As Figure 19As illustrated, the column 1920 of the scanning particle microscope limits the space between the sample 400 and the outlet 1930 of the column to a few millimeters. If a four-phase piezoelectric actuator 1910 is used instead of a tubular piezoelectric actuator, the space between the sample 400 and the column 1920 can be utilized optimally.

[0221] Figure 20 Illustrated are the processing of a sample under the harsh space conditions of a device that combines a scanning particle microscope and a scanning probe microscope or a nano-manipulator 1840, under additional conditions of overlapping the interaction regions of the two microscopes on the sample. In Figure 20 In the diagram 2000 of, the sample is a lithography mask 2010, which includes a substrate 2020 and an absorption pattern element 2030. Particles 2050 that impair the imaging properties of the mask 2010 are present on the substrate 2020 of the mask 2010. The outlet 1930 of the column 1920 of the scanning particle microscope is schematically illustrated above the mask 2010.

[0222] In Figure 20 In the illustrated example, a sacrificial tip 2040 has been deposited ( Figure 20 not shown in) on the measurement tips 120, 150, 170, 220 of the probes 100, 200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670, or on the tip 1850 of the nano-manipulator 1840. The sacrificial tip 2040 can be deposited by means of a charged particle beam (such as an electron beam) under the condition of providing a precursor gas on the measurement tips 120, 150, 170, 220 or the tip 1850. A carbon-containing precursor gas or a metal carbonyl can be used as the precursor gas.

[0223] Figure 21 Repeated is Figure 20 the configuration after the sacrificial tip 2040 has been positioned near or on the particle 2050. For clarity, the column 1920 has been omitted from Figure 21 After the positioning process of the sacrificial tip 2040 has been completed, a precursor gas 2150 is provided in the region of the particle 2050. This is illustrated by the dashed arrow in Figure 21 In addition, an electron beam 2140 is provided in the region of the particle 2050, and the electron beam triggers the local deposition process of the material 2160 on the particle 2050 and the tip of the sacrificial tip 2040.

[0224] After the particle 2050 has been connected to the tip of the measurement tip 2040, the particle 2050 can be removed from the substrate 2020 of the mask 2010 by moving the probe 100, 200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670 or the nanomanipulator 1840. Figure 22 Figure 2200 in

[0225] The advantage that the sacrificial tip 2040 has been deposited on the measurement tip 120, 150, 170, 220 or the tip 1850 is that the particle 2050 removed from the mask 2010 can be removed from the sacrificial tip 2040 during the EBIE (electron beam induced etching) process. Figure 23 Illustrates the removal of the particle 2050 from the sacrificial tip 2040 by the electron beam 2340 and the etching gas 2350 (represented by the dashed arrow).

[0226] After the EBIE process is completed, only the slightly modified sacrificial tip 2040 can be used to remove other particles. Before removing the particle 2050 from the sacrificial tip 2040, the material composition of the particle 2050 can be determined by using the radiation of the electron beam 2340 and the analysis of the X-ray radiation emitted by the particle 2050 in the energy dispersive detector.

[0227] Figure 24 Shows a schematic cross-sectional view of some important components of the device 2400, through which the sample 400 or the lithography element 2010 can be inspected and / or processed. Probes 200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670 with detection structures 230, 530, 1030, 1130, 1230, 1330, 1530, 1630, 1690 can be installed and used in the device 2400. The device 2400 includes a modified scanning particle microscope 2410 in the form of a scanning electron microscope (SEM) 2410 and a scanning probe microscope 2470 in the form of an atomic force microscope (AFM) 2470.

[0228] In Figure 24 In the SEM 2410 of Figure 24(not shown in the figure) is directed to position 2420 on sample 2422, which may include sample 400 or mask 2010. Sample 2422 is disposed on sample stage 2525 (or stage). In addition, the imaging element of column 2417 of SEM 2410 can scan electron beam 160 over sample 2422. Sample 2422 can be inspected using electron beam 2415 of SEM 2410. In addition, electron beam 2415 can be used to induce a particle beam-induced deposition process and / or an EBIE process. Additionally, electron beam 2415 of SEM2410 can be used to analyze particle 2050. Further, electron beam 2415 can be used to sense probes 200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670 of scanning probe microscope 2470.

[0229] Detector 2427 registers electrons backscattered from electron beam 2415 by sample 2422 and secondary electrons generated by electron beam 2415 in sample 2422. In addition, when scanning (one or more) markers 1030, 1240, 1260, 1690 applied to probes 1100, 1200, 1670, detector 2427 identifies the secondary electrons generated. Detector 2427 disposed in electron column 2417 is referred to as an "in-lens detector". In various embodiments, detector 2427 can be mounted in column 2417. Detector 2427 can also be used to detect electrons backscattered from sample 2422 or probes 100, 200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670 or detection structures 230, 530, 1030, 1130, 1230, 1330, 1530, 1630, 1690 applied to probes 200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670. Detector 2427 is controlled by control device 2430 of device 2400. In addition, device 2400 includes Figure 2 detection system 290. Detection system 290 is also controlled by control device 2430.

[0230] Device 2400 includes a third detector 2435. Third detector 2435 is designed to detect electromagnetic radiation, particularly electromagnetic radiation in the X-ray region. Thus, detector 2435 facilitates the analysis of particle 2050 excited by electron beam 2415 to determine the material composition of the particle. During the analysis of particle 2050, sample stage 2425 is lowered and / or sample 2422 is removed from the beam direction of electron beam 2415. Detector 2435 is also controlled by control device 2430.

[0231] The control device 2430 and / or the computer system 2440 can set parameters of the electron beam 2415 for an induced deposition process or an EBIE process and for analyzing particles 2050. In addition, the control device 2430 of the device 2400 receives measurement data from the detector 2427. The control device 2430 can generate an image from the measurement data, which is presented on the monitor 2437. In addition, the control device 2430 can receive measurement data from the secondary electrons 260 of the detection system 290 and display the measurement data on the monitor 2437 of the computer system 2440. In addition, the control device 2430 can include an ASIC, which can perform a fast (<10 μs) coordinate transformation between the coordinate system of the sample stage 2425 and the coordinate systems of the probes 100, 200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670. In addition, the computer system 2440 or the control unit can include a signal processing unit 1750, which matches the excitation of the vibrations of the probes 100, 200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670 with the scanning of the electron beam 2415.

[0232] As already explained above, the electron beam 2415 of the modified SEM 2410 can be used for an electron beam induced deposition process and an EBIE process. Figure 24 The exemplary scanning electron microscope 2410 has three different supply containers 2445, 2450 and 2455 for the purpose of performing these processes.

[0233] The first supply container 2445 stores a first precursor gas, such as metal carbonyl (e.g., chromium hexacarbonyl (Cr(CO)6)) or a carbon-containing precursor gas (such as pyrene). Other carbon-containing precursor gases are also specified above. With the precursor gas stored in the first supply container 2445, the sacrificial tip 2040 or the connection material 2160 can be deposited on the sacrificial tip 2040 or the particles 2050 in a local chemical reaction, while the electron beam 2415 of the SEM 2410 acts as an energy provider to decompose the precursor gas stored in the first supply container 2445 at the location where the material should be deposited. This means that the combination of the electron beam 2415 and the precursor gas 2150 results in an EBID (electron beam induced deposition) process for the local deposition of the sacrificial tip 2014 and / or the connection material 2150. The modified SEM 2410 forms a deposition device in combination with the first supply container 2445.

[0234] The electron beam 2415 can be focused to a spot diameter of a few nanometers. Thus, the EBID process allows for local deposition of the connecting material 2150 with a spatial resolution in the nanometer range of the lower double digits.

[0235] In Figure 24 the device 2400 illustrated in, the second supply container 2450 stores an etching gas, which makes it possible to perform an electron beam induced etching (EBIE) process. By means of the electron beam induced etching process, particles 2050 can be removed from the sacrificial tip 2040. The etching gas 2350 can 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). Thus, the modified SEM 2410 and the second supply container 2450 together form a separate device.

[0236] Additional gases can be stored in the third supply container 2455, and the additional gases can be added, if necessary, to the etching gas 2350 kept available in the second supply container 2450 or to the precursor gas 2150 stored in the first supply container 2445. Alternatively, the third supply container 2455 can store a second precursor gas or a second etching gas.

[0237] In Figure 24 the scanning electron microscope 2410, each of the supply containers 2445, 2450, and 2455 has its own control valve 2446, 2451, and 2456 to facilitate monitoring or controlling the amount of the corresponding gas supplied per unit time, i.e., the gas volume flow rate at the position 2420 where the electron beam 2415 impinges on the sample 2422. The control valves 2446, 2451, and 2456 are controlled and monitored by the control device 2430. Using this, the partial pressure conditions of the gas supplied at the processing position 2420 can be set for performing EBID and / or EBIE processes in a wide range.

[0238] Furthermore, in Figure 24 the exemplary SEM 2410, each of the supply containers 2445, 2450, and 2455 has its own gas feed line system 2447, 2452, and 2457, which terminate with nozzles 2448, 2453, and 2458 in the vicinity of the impingement point 2420 of the electron beam 2415 on the sample 2422.

[0239] The supply containers 2445, 2450, and 2455 may have their own temperature setting elements and / or control elements, which allows for both cooling and heating of the corresponding supply containers 2445, 2450, and 2455. This enables storage at the respective optimal temperatures and in particular the provision of precursor gas and / or etch gas 2350 (not shown in Figure 24 shown).

[0240] The control device 2430 can control the temperature setting elements and temperature control elements of the supply containers 2445, 2450, 2455. During the EBID and / or EBIE process, the temperature setting elements of the supply containers 2445, 2450, 2455 can also be used to set the vapor pressure of the stored precursor gas(es) 2150 by selecting an appropriate temperature.

[0241] The device 2400 can include more than one supply container 2445 in order to store two or more precursor gases 2150. In addition, the device 2400 can include more than one supply container 2450 in order to store two or more etch gases 1650.

[0242] It can be operated under ambient conditions or in the vacuum chamber 2460 Figure 24 of the scanning electron microscope 2410 illustrated therein. A negative pressure relative to the ambient pressure in the vacuum chamber 2460 is required to implement the EBID and EBIE processes. For this purpose, Figure 24 the SEM 2410 in -40 includes a pump system 2462 that generates and maintains the negative pressure required for the vacuum chamber 2460. In the case of the closed control valves 2446, 2451, and 2456, a residual gas pressure of <10 Figure 24 Pa is achieved in the vacuum chamber 1460. The pump system 2462 can include separate pump systems for: the upper part of the vacuum chamber 2460 that provides the electron beam 2415 of the SEM 2410, and the lower part 2465 or reaction chamber 2465 ( Figure 24 not shown).

[0243] Additionally, Figure 24 the exemplary device 2400 illustrated in

[0244] In Figure 24The measuring head 2475 of the scanning probe microscope 2470 is illustrated in the device 2400. The measuring head 2475 includes a holding device 2480. The measuring head 2475 is fixed to the frame of the device 2400 by the holding device 2480 ( Figure 24 not shown in). A piezoelectric actuator in the form of a four-phase piezoelectric actuator 1910 is attached to the holding device 2480 of the measuring head 2475, and the piezoelectric actuator 1910 promotes the movement of the free end of the piezoelectric actuator 1910 in three spatial directions ( Figure 24 not shown in). The probe 200 is fixed to the free end of the piezoelectric actuator 1910. However, the four-phase piezoelectric actuator 1910 can also receive the probes 100, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670 ( Figure 24 not shown in). The free end of the cantilever 110 of the probe 200 has a detection structure 230 in the form of a measurement tip 220 and a detection area 230.

[0245] As Figure 24 indicated by the arrow, the sample stage 2425 can be moved in three spatial directions relative to the measuring head 2475 of the AFM 2470 and / or the incident point 2420 of the electron beam 2415 by the positioning system 2427. In Figure 24 the example of, the positioning system 2427 is implemented in the form of a plurality of micromanipulators or displacement elements. The movement of the sample stage 2425 in the sample plane (i.e., the xy plane, which is perpendicular to the beam direction of the electron beam 2415) can be controlled by two interferometers ( Figure 24 not shown in). In an alternative embodiment, the positioning system 2427 can additionally include a piezoelectric actuator ( Figure 24 not shown in). The positioning system 2427 is controlled by the signal of the control device 2430. In an alternative embodiment, the control device 2430 does not move the sample stage 2425, but moves the holding device 2480 of the measuring head 2475 of the AFM2470. In addition, it is possible that the control device 2430 performs rough positioning of the sample 2422 or the mask 2010 in the height (z direction), and the piezoelectric actuator 1910 of the measuring head 2480 performs precise height setting of the AFM 2470. The control device 2430 can be part of the computer system 2440 of the device 2400.

[0246] The AFM 2470 can be used to position the probes 100, 200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670 relative to the particle 2050. Additionally, the AFM 2470 can be used to remove the probes 200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670 carrying the particles 2050 from the lithography mask 2010 by moving.

[0247] Figure 25 A cross-section of the device 2500 is shown, which can also be used to inspect and / or process lithography elements. Different from the device 2400, the device 2500 operates without changing the probe 100 of the scanning probe microscope 2470. Instead of Figure 24 the electron beam 2415 in, the device 2500 uses an optical pointer system 2550 to detect the deflection of the probe 100 of the scanning probe microscope 2470. The electron source 2412 (or more generally a particle source) generates the electron beam 2415 or a charged particle beam. Two parts 2505 and 2515 of the beam optical unit focus the electron beam 2415 onto the exit 2590 of the lens 2510. The detector 2427, explained in the context of Figure 24 , is located in the column 1920 of the device 2500.

[0248] The modifications taken on the scanning electron microscope 2410 are described below in order to partially guide the optical pointer system 2550 inside the column 1920 of the scanning electron microscope. The column 1920 of the scanning electron microscope includes a window 2580 to couple or decouple the optical radiation of the optical pointer system 2550 from the vacuum environment inside the column 1920. The lens 2510 is attached to the exit 1930 of the column 1920, which decouples the radiation guided inside the column 1920 from the column 1920 or couples the light reflected by the probe 100 into the column 1920.

[0249] Figure 25 The exemplary optical pointer system 2550 in uses a laser system 2520 (such as a semiconductor laser) to direct the light 2560 through the window 2580 via the deflection mirror 2530 and the lens 2510 onto the cantilever 110 of the probe 100. The light 2570 reflected by the probe 100 or the top side 115 of the cantilever 110 of the probe 100 is collected by the lens 2510 and directed via the deflection mirror 2530 and the window 2580 onto the light detector 2540. As an example, the photodetector 2540 can be implemented as a quadrant photodiode. To prevent electrostatic charging caused by electrons scattered inside the column 1920, the optical window 2580, the deflection mirror 2530, and the lens 2510 can be coated with an optically transparent and conductive layer, such as an indium tin oxide layer.

[0250] Figure 26 The diagram 2605 in shows a cross-sectional view of some components of a second exemplary embodiment of an optical light pointer system 2650, which allows a combination of a scanning particle microscope 2410 and a scanning probe microscope 2770 to have an overlapping interaction region 2660 without negatively affecting the capabilities of the two tools 2410 and 2470. The scanning particle microscope is illustrated by the lower part 2515 of the beam optical unit of the scanning electron microscope 2410. An electron beam 2415 exits the scanning particle microscope 2410 at the output 1930 of the beam optical unit 2515 or column 1920, and the electron beam is incident on a sample 400 in the interaction region 2660.

[0251] The probe 2600 of the scanning probe microscope 2470 is positioned below the column 1920, and the measurement tip 120 of the probe also interacts with the sample 400 in the interaction region 2660. A reflection element 2630 is attached to the probe 2600 on the front side 115 of the probe 2600 at an angle other than zero with respect to the surface of the cantilever 110. The light pointer system 2650 Figure 26 A light source (not shown in ) radiates light or optical radiation 2610 onto the reflection element 2630 via a lens 2670. The reflection element 2630 reflects the optical radiation 2620 through the lens 2670 of the light pointer system 2650 to a detection system (also suppressed in ) of the light pointer system 2650. Figure 26 The reflection element 2630 may include a mirror. However, the reflection element 2630 may also have a curved form, and thus, in addition to reflecting the optical radiation 2610, the reflected radiation 2620 is additionally imaged.

[0252] The reflection element 2630 may be arranged at an angular range of 50° to 85° with respect to the surface 115 of the cantilever 110 of the probe 2600. In Figure 26 the example presented, the angle of the reflection element 2630 is approximately 75°. The reflection element 2630 may include a metal coating, such as a gold, silver, or aluminum coating.

[0253] Figure 27 A schematic cross-sectional view of a device 2700 is shown, which combines a scanning electron microscope 1710, 2410, a nanomanipulator 1840, and an energy-dispersive detector 2435 for X-ray radiation. The columns 1920 of the scanning electron microscopes 1710, 2410 are inclined with respect to the sample normal in the device 2700 to provide more space for processing the sample 400 using the nanomanipulator 1840. In Figure 17 and 24 the components of the device 2700 have been explained in the context of the discussion.

[0254] Figure 28 The flow chart 2800 in Figure 28 provides an overview of the processing procedure that can be implemented on the sample 400 by any one of the devices 2400 and 2700. In step 2805, the method begins. In the first step 2810, the scanning electron microscope 2410 is switched to the force measurement mode; that is, the electron beams 240, 1040 are positioned on the detection regions 230, 530 of the probes 200, 500, 1000, or the electron beam 1140 scans over the (one or more) markers 1130, 1240, 1460 or the detection structures 1130, 1230, 1690 of the probes 1100, 1200, 1670. The electron beam can also be scanned in a line scan over the detection structures 1330, 1530, 1630, 1670 of the probes 1300, 1500, 1600, 1640.

[0255] Therefore, in step 2820, the measurement tips 120, 150, 170, 220 of the probes 100, 200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670 are brought close to the sample 400; during this process, the deflection of the probes 100, 200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670 is monitored by means of the electron beams 240, 1140. Once the approaching process has been completed, in step 2825 the electron beam of the scanning electron microscope 2410 is focused on the sample 400, and an image of the surroundings of the measurement tips 120, 150, 170, 220 is recorded by scanning the sample 400.

[0256] The decision made in the decision box 2830 is whether the processing procedure of the sample 400 is force-controlled (i.e., the electron beam 240 is directed to the detection regions 230, 1030 of the probes 200, 800, 1000 or the markers 1130, 1240, 1260 of the probes 1100, 1200) or image-controlled (i.e., the electron beam 840 scans over the sample 400 during the process).

[0257] If the force control mode is used, then in step 2835 the scanning electron microscope 2410 is switched back to the force measurement mode. In step 2840, the sample 400 is processed by the measurement tips 220 of the probes 200, 800, 900, 1000. During the processing 2840 of the sample 400, for example, the particle 2050 can be displaced on the sample 400, and / or a particle can be removed from the sample 400, as in Figures 20 to 22as explained in the context of. In step 2845, the sample 400 is rescanned by the electron beam 840 in order to verify whether the processing process has been successful. In step 2860, the resulting SEM image is displayed on the monitors 2437 of the devices 2400, 2500, 2700.

[0258] If a decision is made in decision box 2830 to monitor the processing process in an image-controlled manner, then in step 2850 the scanning electron microscope is switched to the imaging mode, i.e., the electron beam 840 scans over the sample 400 during the processing process. In step 2855, the processing of the sample 400 is carried out, and in step 2860 the image of the sample 400 recorded after the processing process has been completed is displayed on the monitor 2437 of the device 2400, 2500 or 2700. In box 2865, the processing process ends.

[0259] Finally, Figure 29 Flowchart 2900 in shows schematically the basic steps of the process of moving particles 2050 from the lithography element 400, 2010. In step 2910, the method starts. In step 2920, a probe 100, 200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670 that is movable relative to the sample 400 or the lithography element 2010 is positioned in the vicinity of the particle 2050 to be moved. In the next step 2930, using a charged particle beam 240, 1140 of the scanning particle microscope 2410, a light pointer system 2550, 2650 that is at least partially guided in the scanning particle microscope 2410, or a light pointer system 2650 including a reflective structure 2630 arranged on the probe 2600, the reflective structure being arranged at a non-zero angle on the front side 115 of the probe 2600, for the purpose of determining the deflection of the probe 100, 200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670 during the positioning. Then, in step 2940, the particle 2050 is moved by moving the probe 100, 200, 500, 800, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1640, 1670 relative to the sample 400, 2010. Finally, in step 2950, the method ends.

Claims

1. An apparatus for inspecting and / or processing a sample, the apparatus comprising: a. A scanning particle microscope for providing a charged particle beam, the charged particle beam being capable of being directed onto the surface of the sample; and b. A scanning probe microscope having a deflectable probe; c. wherein a detection structure is attached to the deflectable probe, d. wherein, the apparatus is adapted to determine the deflection of the deflectable probe by positioning the charged particle beam on the detection structure and detecting the emission of at least one of the charged secondary electrons and the backscattered electrons from the detection structure.

2. The device according to claim 1, wherein The scanning particle microscope is configured to perform: scanning the charged particle beam over the detection structure.

3. The device according to claim 2, wherein The scanning particle microscope is configured to perform: performing a line scan of the charged particle beam over the detection structure.

4. The device according to any one of the preceding claims, wherein, The material composition of the detection structure is different from the material composition of the deflectable probe.

5. The device according to claim 1 or 2, wherein The detection structure has a cylindrical, conical, rod-shaped or n-sided structure, where n≥3.

6. The device according to claim 1 or 2, wherein, The detection structure includes at least two separate adjacent materials having different atomic numbers.

7. The device according to claim 1 or 2, wherein, The detection structure includes a detection region configured to optimize the emission of charged secondary electrons and / or backscattered electrons.

8. The device according to claim 1 or 2, wherein The detection structure includes at least one planar element, and wherein the normal vector of the planar element is directed substantially parallel to the longitudinal axis of the deflectable probe.

9. The device according to claim 8, wherein, The detection structure includes at least two planar elements arranged along the longitudinal axis of the deflectable probe.

10. The device according to claim 1 or 2, wherein, The detection structure includes at least one marker.

11. The device according to claim 1, further comprising an optical light pointer system, wherein, The detection structure includes a reflection structure configured to reflect the optical radiation of the optical light pointer system, and wherein the reflection structure is arranged at an angle other than zero with respect to the front side of the deflectable probe.

12. The device according to claim 1 or 2, wherein The deflectable probe has an opening implemented such that the charged particle beam can be directed through the opening onto the sample.

13. The device according to claim 1 or 2, wherein, The deflectable probe is conductive for the purpose of shielding and / or compensating the electrostatic charge of the sample.

14. The apparatus according to claim 1 or 2, further comprising a detector for detecting X-ray radiation.

15. A method for moving particles on a lithography sample, comprising the steps of: Positioning a deflectable probe near the particles to be moved, the deflectable probe having a detection structure attached thereto and being movable relative to the lithography sample; Using the charged particle beam of a scanning particle microscope for the purpose of determining the deflection of the deflectable probe during the positioning by positioning the charged particle beam on the detection structure and detecting the emission of at least one of the charged secondary electrons and the backscattered electrons from the detection structure; and Moving the particles by moving the deflectable probe relative to the lithography sample.

16. The method according to claim 15 further comprises the following steps: Imaging the lithography sample and / or the particles using the charged particle beam of the scanning particle microscope.

17. The method according to claim 15 or 16 further comprises the following steps: Connecting the deflectable probe to the particles.

18. A computer program product comprising instructions which, when executed by a computer system, cause the apparatus according to any one of claims 1 to 14 to carry out the method steps according to any one of claims 15 to 17.

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