JP2010114082A - Gas electric field ion source of dual mode - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ion beam device of a single column which enables observation and processing of a sample. <P>SOLUTION: This focusing ion beam device focuses the ion beam drawn out from a gas electric field ion source and irradiates it to a sample 24, and processes and observes the sample. The ion source is equipped with an emitter chip 13 which forms an ion, a heating means 15 that heats the ion, gas introduction ports 110, 112 that introduce the first gas and at least one of the second gases, and a controller 172 that switches a first emitter chip temperature and a second emitter chip temperature in order to form the ion beam of either gas. The first gas is a light gas and used for an observation mode, and the second gas of at least one is a heavy gas (inert gas, reactive gas) and used for a sputtering mode (in case of the inert gas) or a reaction mode (in case of reactive gas). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  [0001] The present invention relates to charged particle beam devices and methods of operating charged particle beam devices. In particular, the present invention relates to a focused ion beam device having a gas field ion source, particularly for sample imaging, inspection and structuring. The invention further relates to a gas field ion source column for dual mode operation, as well as a method for operating a gas field ion source having various modes of operation. More specifically, the present invention relates to a focused ion beam device and a method of operating a focused ion beam device.

  [0002] Technologies such as microelectronics, micromechanics, and biotechnology are creating great demand for structuring and exploring samples on the nanometer scale. Micrometer and nanometer scale process control, inspection, or structuring is often performed by charged particle beams. The investigation or structuring is often performed by a charged particle beam that is generated and focused in a charged particle beam device. Examples of charged particle beam devices are electron microscopes, electron beam pattern generators, ion microscopes, and ion beam pattern generators. Charged particle beams, especially ion beams, provide shorter spatial resolution than photon beams because of their shorter wavelengths at comparable particle energies.

  [0003] In manufacturing a semiconductor device or the like, usually, a plurality of observation steps and a sample modification step are performed. A typical system comprises an electron beam column for sample observation, imaging, testing or inspection, and an ion beam column for sample patterning or material modification. These “dual beam” systems are highly complex and therefore expensive.

  In light of the above, the present invention provides a focused ion beam device according to independent claim 1, a method of operating a focused ion beam device according to independent claim 10, and a focused ion beam device according to independent claim 15. And a focused ion beam device according to independent claim 17.

  [0005] According to one embodiment, a focused ion beam device is provided. The focused ion beam device includes an ion beam column configured to accommodate a gas field ion source emitter having an emitter tip and an emitter region for generating ions, and a heating configured to heat the emitter tip. Means, one or more gas inlets configured to introduce a first gas and at least one second gas into the emitter region, an ion beam of ions of the first gas, or the at least A controller configured to switch between a first emitter tip temperature and at least a second emitter tip temperature to generate an ion beam of ions of one second gas.

  [0006] According to another embodiment, a method of operating a focused ion beam device is provided. The method includes extracting an ion beam of at least one of a first gas and at least one second gas to an emitter having an emitter tip in an emitter region where ions are generated. Biasing a potential to supply a voltage; heating to a first emitter tip temperature; emitting an ion beam of the first gas; and at least one second emitter tip temperature. Heating and emitting at least one ion beam of the at least one second gas.

  [0007] According to a further embodiment, an ion beam column containing an emitter having an emitter tip and an emitter region for generating ions of a first gas and at least one second gas; Means for switching between an emitter tip temperature and at least one second emitter tip temperature, wherein the first gas is selected from the group consisting of hydrogen and helium, A focused ion beam device is provided in which at least one second gas has an atomic weight of 10 g / mol or more.

  [0008] According to yet further embodiments, a method of operating a focused ion beam device, wherein at least two different ion beams of a first gas and at least one second gas are at least one of the gases. A continuously generated method is provided by switching between at least two different emitter tip temperatures, each resulting in one ionization.

  [0009] Further advantages, features, aspects and details that can be combined with the embodiments described herein are apparent from the dependent claims, the description and the drawings.

  [0010] Some embodiments also relate to an apparatus for performing the methods disclosed herein, comprising an apparatus portion for performing the steps of the methods described herein. . The steps of these methods can be performed in hardware components, a computer programmed with appropriate software, any combination of the two, or any other manner. Furthermore, embodiments according to the invention also relate to a method of operating the apparatus described herein. Each step of the method for performing each function of the device is also encompassed.

FIG. 2 shows a schematic diagram of each part of a charged particle beam device in the form of a focused ion beam device having a first gas inlet, a second gas inlet, and a heater according to embodiments described herein. FIG. 2 shows a schematic diagram of each part of a charged particle beam device in the form of a focused ion beam device having a first gas inlet, a second gas inlet, and a heater according to embodiments described herein. FIG. 2 shows a schematic diagram of an emitter tip of a gas field ion source and the principle of operation of an emitter tip according to embodiments described herein. FIG. 2 shows a schematic diagram of parts of a charged particle beam device in the form of a focused ion beam device having a first gas inlet and a second gas inlet according to embodiments described herein. FIG. 6 shows a schematic diagram of each part of a charged particle beam device in the form of a focused ion beam device having a first gas inlet, a second gas inlet, and a common gas inlet according to embodiments described herein. Yes. 1 shows a schematic diagram of an emitter tip of a gas field ion source and the principle of operation of the emitter tip in a first mode of operation according to embodiments described herein. FIG. FIG. 2 shows a schematic diagram of an emitter tip of a gas field ion source and the principle of operation of the emitter tip in a second mode of operation according to embodiments described herein. 1 shows a schematic diagram of each part of a charged particle beam device in the form of a focused ion beam device having a first gas inlet, a second gas inlet, and a third gas inlet according to embodiments described herein. FIG. ing. FIG. 2 shows a schematic view of parts of a charged particle beam device in the form of a focused ion beam device having a gas inlet and a valve according to embodiments described herein. FIG. 2 shows a schematic view of parts of a charged particle beam device in the form of a focused ion beam device having a gas inlet and a valve according to embodiments described herein. FIG. 2 shows a schematic diagram of parts of a charged particle beam device in the form of a focused ion beam device having a gas inlet, a valve, and a vacuum vessel according to embodiments described herein. FIG. 2 shows a schematic diagram of parts of a charged particle beam device in the form of a focused ion beam device having a gas inlet, a valve, and a vacuum vessel according to embodiments described herein.

  [0011] In a manner that allows the above features of the present invention to be more fully understood, the present invention, briefly outlined above, may be more fully described by reference to embodiments. The accompanying drawings relate to embodiments of the present invention and are described as follows.

  [0012] Reference will now be made in detail to various embodiments of the invention, one or more examples of which are illustrated in the figures. Each embodiment is presented for purposes of illustrating the invention and is not intended to limit the invention. For example, features illustrated and described as part of one embodiment can be used in another embodiment or in conjunction with another embodiment to yield further embodiments. The present invention encompasses such variations and variants.

  [0013] Without limiting the scope of protection of the present application, in the following, the charged particle beam device or components thereof will be described as an example charged particle beam device including detection of secondary electrons. Nonetheless, the present invention provides an apparatus and component for detecting particulates such as secondary and / or backscattered charged particles in the form of electrons or ions, photons, X-rays, or other signals to obtain an image of the sample. It is applicable to.

  [0014] Generally speaking, a microparticle is understood as an optical signal if the microparticle is a photon, and a particle if the microparticle is an ion, atom, electron, or other particle.

  [0015] In the following description of the drawings, the same reference numbers refer to the same components. In general, only the differences with respect to the individual embodiments are described.

  [0016] As used herein, "sample" includes, but is not limited to, semiconductor wafers, semiconductor workpieces, and other workpieces such as memory disks. Embodiments of the present invention can be applied to any workpiece on which material is deposited or structured. The sample comprises a surface to be structured or a surface on which a layer is deposited, an edge, and typically a chamfer.

  [0017] According to embodiments described herein, a single column charged particle beam device is provided that enables high resolution imaging and sample modification. Therefore, it is possible to provide a simplified single column operation. Furthermore, in light of the fact that one column can be omitted, a cost reduction can be achieved.

[0018] In general, a focused ion beam device can be based on, for example, a liquid metal ion source or a gas ion source. Ions in a gas ion source can be generated by bombarding electrons, atoms, or ions with gas atoms or molecules, or by exposing gas atoms or molecules to a strong electric field or irradiation. Thus, it has been found that noble gas ion sources are potential candidates for focused ion beam FIB applications. An ion source based on a field ionization process is known as a gas field ion source (GFIS). The ionization process is performed with a high electric field or extraction voltage, each greater than 10 ¹⁰ V / m. For example, an electric field can be applied between an emitter tip provided in a gun chamber that can include a housing in which, in one embodiment, an emitter tip is provided, and a biased extraction opening.

[0019] The emitter tip is biased to a positive potential with respect to the downstream extraction opening, thereby generating an electric field strong enough to ionize the gas atoms near the tip of the emitter unit. The region near the emitter that provides the desired electric field or, more generally, where ions are generated can be referred to as the emitter region. A gas pressure of 10 ⁻⁶ mbar to 10 ⁻² mbar is desirable near the tip of the emitter unit. This allows a sufficient amount of gas atoms or molecules to be supplied to the emitter region on the one hand, and on the other hand, emitted ions can be hindered by gas molecules supplied into the gun chamber, as described in more detail below. A gas gradient is typically used so that there is no.

  [0020] FIGS. 1A and 1B show a first gas inlet 110 and a second gas inlet 112. FIG. According to the embodiments described herein, various modes of operation can be provided. According to one mode of operation, a light gas such as hydrogen or helium, for example a gas with an atomic weight of less than 10 g / mol, is introduced into the chamber / housing 14 through one of the first and second gas inlets. And an ion beam of ionized light gas can be generated. Light gas ions can be used for viewing or imaging without damaging the sample.

  [0021] According to another mode of operation, a heavier gas, for example another gas such as argon, neon, xenon, or krypton, passes through one of the first or second gas inlets 110 or 112. Introduced into chamber / housing 14. The ionized heavy gas ion beam generated in the gun chamber, i.e., housing 14, is similar to the ion beam of a standard focused ion beam column for sputtering materials. Thus, this heavy gas beam can be used to modify the material, create a cut or groove in the sample, or obtain depth information.

  [0022] In the embodiments described herein, the housing 14 in which the emitter 12 with the emitter tip 13 is provided may be part of an ion beam column. Alternatively, it may be a separate chamber included in the ion beam column. Further, the housing 14 can correspond to an emitter region. Furthermore, the ion beam column itself can provide a housing in which the emitter is located and into which the gas is introduced.

  [0023] Light gas ions do not sputter specimen material and can be used for imaging, testing, observation, and the like. Therefore, light gas ions can have a better resolution than the electron beam because the wavelength of the ion beam is shorter than that of the electron beam.

  [0024] In general, as shown in FIGS. 1A and 1B, the focused ion beam device 100 is schematically described as follows. A housing 14 with a biased gas field ion source emitter tip 13 is provided. In addition, a first (light) gas inlet 110 and a second (heavy) gas inlet 112 are provided. As a result, the first gas and the second gas are supplied to the casing 14 toward the emitter tip 13 toward the emitter region near the emitter. Desired excitation conditions are prepared in the vicinity of the emitter tip. According to various embodiments that can be combined with other embodiments described herein, two gas inlets can be provided in the form of two nozzles, gas channels, or other gas introduction means. It is. According to another embodiment, the two gas inlets supply two gases in the form of a common nozzle, gas channel or other gas introduction means.

  [0025] As shown in FIGS. 1A and 1B, a gas outlet 120 is provided. The gas outlet 120 can be connected to a vacuum pump, an additional vacuum chamber, or other means that assists in evacuating the housing 14 and / or controlling the pressure. Thereby, process parameters for generating the ion beam can be controlled.

  [0026] Typically, a gas pressure gradient can be applied to the gun chamber. Thereby, the gas pressure is higher in the vicinity of the emitter and the emitter tip and decreases toward the extraction electrode. As a result, a sufficient amount of gas can be supplied to the emitter tip and the amount of gas that can hinder ion emission is reduced. According to various examples that can be combined with any of the embodiments described herein, the gas pressure gradient can reach 1e-5 mbar to 5e-3 mbar, typically 1e-4 mbar to 1e-. Can reach 3mbar. Behind the drawer, the gas pressure is further reduced.

  [0027] As shown in FIGS. 1A and 1B, according to some embodiments described herein, a controller 130 may be provided. The controller 130 controls the supply of light gas to the housing 14 and the supply of heavy gas to the housing 14. Further, in embodiments with a separate gas outlet 120, the controller can control the gas outlet, the vacuum system, the vacuum pump, or a corresponding valve. According to further embodiments, controllers 111, 113, and 121 may be provided. These controllers are controllers for individual inlets, outlets, valves, pumps, etc. As indicated by the dashed lines, these controllers can be omitted because they are redundant if the controller 130 can directly control the components.

  [0028] The ion beam is focused by the lens 20 onto the sample 24. According to one embodiment, the lens 20 is an electrostatic lens. Depending on the application, one or more optical elements such as lenses, deflectors, Wien filters, concentrators, alignment units, collimators, acceleration or deceleration units, apertures, etc. are additionally placed in the focused ion beam device. Can do.

  [0029] Generally, the ion beam is deflected by a scanning deflector 26 to raster scan the ion beam over the sample 24 or to position the ion beam at the sample location. Secondary and / or backscattered particles, such as secondary and / or secondary electrons, are detected by the detector 22, particularly when the focused ion beam device is operated in observation mode.

  [0030] According to a further embodiment, a controller 140 may be provided, as shown in FIGS. 1A and 1B. The controller 140 controls the scanning deflector 26 and the detector 22. During the observation mode of the focused ion beam device 100, the device operates in the same manner as a scanning electron microscope. An ion beam having a diameter of several nanometers or less (for example, 1 nm or less) is scanned on the sample 24, for example, raster-scanned in a pattern, vector-scanned, or interlaced scanned on the sample 24. Secondary and / or backscattered electrons or other particulates can be detected with a detector. A time-resolved signal is generated and the controller 140 can correlate the signal at a given time point with a corresponding deflection value. This allows the raster pattern to be assembled into an image by correlating the signal with respect to position on the sample 24.

  [0031] A dual mode gas ion column, on the one hand, supplies the housing 14 with different gases, for example light and heavy gases, and supplies different gases for each mode of operation between the two modes of operation. It can be brought about by switching. According to embodiments described herein that can be individually combined with the details of individual examples, instead of supplying different gas species by switching between different gas supplies, a gas field ion gun May contain a mixture of gases as required. According to the example of the embodiment, it is possible to select various ion species based on different chip temperatures. Furthermore, according to some examples of embodiments, the selection of various ionic species can be performed based on different ionization energies.

  [0032] In light of the above, according to an embodiment that can be combined with any other embodiment disclosed herein, a heater 15 for heating the emitter tip 13 is provided as a heating means.

  [0033] As shown in FIG. 1A, a heater 15 may be connected to the emitter tip 13 for heating. In one example of an embodiment that can be combined with any other example or embodiment disclosed herein, the emitter tip 13 is provided on a filament of a support comprising a filament and a filament base. In this case, the heater 15 can be configured to heat at least one element selected from the group consisting of an emitter tip, a filament, and a filament base. For example, the heater 15 may be a resistance heater. In one embodiment, the heater 15 comprises a heating current source, for example about 10V, having one port connected to one end of the filament and a second port connected to the other end of the filament. it can. In another embodiment, a heater 15 can be connected to the filament base and the emitter tip can be heated via the filament base and filament. As a result, the front part of the emitter tip support, i.e. the part adjacent to the emitter chip, is heated to heat the emitter chip, while the rear part of the emitter tip support, i.e. the front part and the cooling unit (not shown). Cooling is continued for the portion in between. The cooling unit will be described later.

  [0034] In another example of an embodiment that can be combined with any other example or embodiment disclosed herein, the heater 15 is positioned adjacent to the emitter tip. In this case, the heater 15 may not be connected to the emitter chip. For example, the heater 15 can be disposed in the emitter tip region adjacent to the emitter tip, for example, within the housing 14 as shown in FIG. 1B. In such a case, the heater 15 may be at least one element selected from the group consisting of, for example, an electromagnetic heater, an induction heater, a radiation heater, an IR heater, a particle source such as an electron source, and a laser. . As a result, the emitter tip can be heated while continuing to cool the front and / or rear of the emitter tip support.

  [0035] Thus, according to the embodiments described herein, it is possible to achieve a rapid switch between emitter tip cooling and emitter tip heating operations.

  [0036] Further, according to some embodiments described herein, an adjustable power supply 72 is provided to provide an extraction voltage between the emitter tip 13 and the electrode 18. The extraction voltage can be controlled by the controller 172 as described in more detail below. Further, the controller may optionally control the controller 130 to control the partial pressure of the gas.

  FIG. 2 shows the emitter tip 13 and the extraction electrode 18. A voltage source 72 for generating a high electric field is provided between the emitter tip and the extraction electrode. Typically, the emitter tip 13 includes a shank 210 and a tip 212, and in one embodiment may include a super tip. According to various embodiments, the tip 212 provided in the shank 210 may be a tip that includes one, two, three, four, or five or more atoms. The operating principle of ion generation in a gas field ion source is described for one species. As shown in FIG. 2, for example, helium atoms 52 are supplied and ionized to generate helium ions 53.

  [0038] The emitter tip 13 can typically be in communication with a cooling unit (not shown). According to various embodiments that can be combined with any of the embodiments described herein, the cooling unit can include any of the following systems. That is, the cooling unit is a cryogenic cooler, EG, open or closed cycle cooler, open or closed cycle helium cooler, open or closed cycle nitrotin cooler, or combinations thereof, or other coolers. Also good. Particular embodiments may be a pulse tube cooler or a GM cooler (Gifford McMahon cooler).

[0039] When helium gas is supplied to the emitter tip along the direction from the top to the bottom of FIG. 2, helium atoms 52 condense in the shank 210 of the emitter 13. Thus, it is typically desirable to have a shank 210 that provides a sufficiently large surface for the condensation of helium atoms. Surface may typically be in the range of 0.2μm ² ~5μm ^2.

  [0040] As shown by arrow 62, the atoms diffuse toward the tip 212. That is, the movement based on the diffusion caused by the difference in the helium concentration of the shank 210 relative to the chip 212 and the movement based on the drift caused by the electric field can cause the movement of the helium atoms 52 toward the chip 212. As an example, helium typically requires an electric field of about 44 V / nm for ionization. The voltage between the emitter tip 13 and the extraction electrode 18 is selected so that the electric field at the tip 212 provides at least the ionization energy of the species to be ionized. Therefore, it should be considered that the electric field at the tip is higher than any other point on the emitter due to the small size of the tip. Accordingly, helium atoms 52 are ionized at the chip 212 and emitted as helium ions 53.

  [0041] FIGS. 3A and 3B show further embodiments of portions of focused ion beam columns 300a and 300b, respectively. Here, the gun chamber 17 is provided in the upper part of the column 16. An emitter 12 is attached to the emitter holder 10. The cooling unit 30 is provided so as to have heat conduction between the cooling unit 30 and the emitter chip 13 via the emitter holder 10. The extraction electrode 18 is provided for the voltage between the emitter tip 13 and the extraction electrode. The connection from the emitter to the extraction electrode is connected via a voltage source 72 that can supply various voltages. In addition, as shown in FIG. 3A, the first gas inlet 110 and the second gas inlet 112 provide a first gas and a second gas, respectively, such that a gas mixture is brought to the emitter. To the housing. According to some embodiments described herein, an emitter 12 including an emitter tip 13 can be provided in a housing 14, the housing 14 being a condensation surface that is large enough for a shank of the emitter tip. Can be configured such that gas is supplied to the emitter 13 from above to below. A gas outlet 120 can be provided for exhaust and / or control of the pressure in the housing 14. Ions generated in the vicinity of the emitter tip 13 are accelerated toward the extraction electrode and guided along the optical access 102.

  [0042] As shown in FIG. 3B, according to some embodiments, the first gas inlet and the second gas inlet are common gas inlets that supply a gas mixture to the emitter region. It is possible to supply gas to the mouth 310. According to embodiments described herein, having two separate gas inlets, having two separate gas inlets that route each gas to a common gas inlet, or a gas mixture The gas mixture can be supplied to the vicinity of the emitter tip by either supplying through only one gas inlet.

  [0043] According to yet further embodiments, more than two gases, ie more than two gas inlets, may be provided to route gas to a common gas inlet. Furthermore, it is possible to send more than two gases, for example a mixture of three or four gases, directly to the emitter region.

  [0044] The dual-mode or multi-mode operation provided in accordance with the embodiments described herein may be better understood with respect to FIGS. As an example, mention may be made of helium as a light (first) gas and argon as a second (heavy) gas. It should be understood that according to other embodiments, any combination of gases described herein may be used.

  [0045] As described above, according to some examples of embodiments, the selection of various ionic species can be based on different ionization energies. Thus, one possibility for switching between gases is to switch the extraction voltage of the emitter tip 13.

  In FIG. 4, a voltage is supplied between emitter 13 and extraction electrode 18 by voltage source 72. The voltage source can be controlled by the controller 172. According to some embodiments, the controller 172 can communicate with a controller 130 (not shown in FIG. 4) for supply of the first and second gas inlets. The emitter comprises a shank 210 and a tip 212. In the embodiment shown in FIG. 4, a mixture of helium atoms 52 and argon atoms 54 shown in different shapes is supplied so that it can be condensed or deposited on the shank 210 of the emitter tip 13. Typically, helium requires an electric field of about 44 V / nm for ionization, while argon requires an electric field of about 22 V / nm for ionization. For example, if a helium ion beam of helium ions 53 is to be formed, the voltage source 72 provides an extraction voltage that results in an electric field of at least about 44 V / nm or slightly higher on at least a portion of the surface of the chip. Adjust to add to position 212. As shown in FIG. 4, helium atoms 52 condense or deposit on the shank 210 and move toward the tip 212 by diffusion or drift, where the helium atoms are ionized. As shown in FIG. 4, at the voltage applied between the emitter tip and the extraction electrode, helium atoms 52 are ionized in the vicinity of the tip in view of the higher electric field due to the small radius of the tip. Since the ionization energy of argon is significantly lower than the ionization energy of helium, the argon atoms 54 are ionized into argon ions 55 before reaching the tip 212. Thus, argon ions are generated in the shank 210 and are ionized early while diffusing along the emitter shank, and therefore do not reach the emitter tip. In view of the positive potential of the shank 210, the argon ions are pushed back by the shank and do not form a collimated beam at the tip. Since argon ions are emitted from a much larger range than helium ions, argon does not form a collimated beam under the conditions of the voltage source shown in FIG.

  [0047] According to some embodiments that can be combined with other embodiments described herein, a magnetic deflection when multiple argon ions are believed to travel along the optical access and reach the sample. It is contemplated that a mass separator 742 (eg, see FIGS. 1A and 1B) may be provided, such as a filter or a Wien filter.

  [0048] In the second mode of operation shown in FIG. 5, the voltage source 72 is such that the extracted voltage provides an electric field on at least a portion of the surface of the chip of about 22 V / nm or slightly above this value. Adjusted to apply voltage. As a result, the maximum electric field is much lower than that required for helium ionization. Therefore, only argon is ionized and argon ions 55 are generated in the vicinity of the chip 212. As described above, the argon atoms condense in the shank 210 of the emitter 13 and diffuse and / or drift toward the tip due to the concentration gradient and / or electric field along the shank 210. Since the electric field strength shown in FIG. 5 is too low for helium ionization, an argon beam is formed and guided along the optical access through the extraction electrode 18 toward the sample.

  [0049] As shown in FIG. 5, helium atoms 52 condense or deposit on the shank 210 of the emitter 13. Since helium is not emitted from the emitter tip, it may accumulate on the tip. Depending on operating conditions, the accumulated helium can reduce the supply of argon along the shank 210. If the supply of argon along the shank to the tip 212 decreases to an unacceptable amount, high field strength is emitted to radiate helium atoms and reduce the amount of helium atoms that condense on the emitter tip 13. A short pulse with can be applied. According to a further or alternative embodiment, the emitter tip can be heated, for example by a short current pulse through a support wire, in order to evaporate the absorbed gas. As a result, similar effects or further effects can be produced.

  [0050] According to some embodiments that can be provided in combination with other embodiments described herein, the ratio between "light" gas and heavy gas is adjusted according to requirements. be able to. Since the heavy species are used for etching or the like to be performed at high speed, the concentration of the heavy species may be higher than the concentration of He.

  [0051] Switching the potential difference between the emitter tip 13 and the extraction electrode 18, or other adjustments to change the electric field at the tip 212, can produce different modes of operation with different ion beam emissions.

According to embodiments described [0052] herein, the gas mixture ^can be supplied in a range of 10 -4 mbar~10 ^-2 mbar.

  [0053] According to embodiments described herein that can be combined with other embodiments described herein, at least two different voltages are provided by power supply 72. According to the first operation mode, a voltage corresponding to a high electric field at the position of the tip of the emitter tip 13 where the electric field is strongest is supplied. As a result, the emitter tip provides three different regions for the first low electric field and the second higher electric field. At the uppermost end of the shank 210, the electric field is lower than the first and second electric fields. In the middle portion of the shank 210, the electric field is equal to the first lower electric field so that the first species can be ionized. Furthermore, in the vicinity of the tip having the smallest curvature, an electric field equal to the second higher electric field or at least a second electric field is provided. As a result, according to this mode of operation, the two species are ionized. However, only one of them forms a storage beam at the tip of the emitter tip 13.

  [0054] In the second mode of operation, the electric field is lower than the first lower electric field in most of the emitter tip 13. The first lower electric field is reached only in the part of the emitter tip with the smallest curvature or in the vicinity of this position. Thus, only one species is ionized.

  [0055] As described above, the selection of various ionic species can be made by selecting the temperature of the emitter tip. Therefore, another possibility for switching between gases is to switch the temperature of the emitter tip 13.

  [0056] According to an example of embodiment, the ionic current of the first gas can be maximized at the first chip temperature while providing a constant electric field by establishing a constant extraction voltage, while The ion current of the second gas can be maximized at the second chip temperature. A constant extraction voltage may be, for example, an extraction voltage having sufficient emission current at a cooling temperature at which one of the gases is commonly used, and sufficient emission at a cooling temperature at which the other of the gases is generally used. The extraction voltage may be selected from a range between the extraction voltage having a current. For example, when an extraction voltage is applied to the emitter tip 13 that results in an electric field in the range of about 20 V / nm to about 50 V / nm on at least a portion of the tip surface, the argon ion current is maximized at a tip temperature of about 80K. While He has a maximum of release at about 20K. Therefore, the preferentially emitted gas is selected by switching the temperature of the chip.

  [0057] For example, when a closed cycle He cryocooler is used to cool the emitter tip, such as a pulse tube cooler, Gifford McMahon cooler, Stirling cooler, etc. Can always be achieved by operating at a lower temperature than required for helium. For example, when a higher temperature is required for argon emission, the heater 15 such as a resistance heater located near the emitter tip can be turned on to increase the temperature. When changing the temperature of the chip, the cooler itself having a large heat capacity remains at the same temperature, so that a quick switching of the temperature is achieved in this way.

  In the embodiment described with reference to FIG. 4, a constant voltage can be supplied between emitter 13 and extraction electrode 18 by voltage source 72. The heater 15 connected to the emitter chip 212 is controlled by a controller 172 that can also control the voltage source 72. In order to control the chip temperature, a temperature sensor (not shown) connected to the controller 172 can be provided, for example, on the emitter chip support. As a cooling unit, for example, a closed cycle He cryogenic cooler (not shown) is connected to the emitter tip support and is used to cool the emitter tip 13. According to some embodiments, the controller 172 can communicate with the controller 130 for the supply of the first and second gas inlets. The emitter comprises a shank 210 and a tip 212 (eg, a tip containing a very sharp tip or supertip). In the embodiment shown in FIG. 4, a mixture of helium atoms 52 and argon atoms 54, represented by separate shapes, is supplied so that it can be condensed or deposited on the shank 210 of the emitter tip 13. Helium requires an electric field of about 44 V / nm for ionization, while argon requires an electric field of about 22 V / nm for ionization. For example, the voltage source 72 is adjusted to apply an extraction voltage at the location of the chip 212 that results in an electric field on at least a portion of the surface of the chip, for example, about 44 V / nm or slightly higher. Furthermore, the heater 15 is not operated so that the emitter tip 13 is brought to a temperature of, for example, about 20K. As shown in FIG. 4, helium atoms 52 and argon atoms 54 condense or deposit on the shank 210 and move toward the tip 212 by diffusion or drift. Since the tip temperature matches the temperature at which helium emission is maximized (also referred to herein as the maximum emission temperature), helium atoms are ionized. As shown in FIG. 4, at the voltage supplied between the emitter tip and the extraction electrode, helium atoms 52 are ionized in the vicinity of the tip. Since the maximum discharge temperature of argon (80K) is significantly higher than the maximum discharge temperature of helium (20K), a large amount of helium atoms 52 is ionized, while the argon atoms 54 are hardly ionized. Thus, a parallel beam of helium ions 53 is generated under the voltage and temperature conditions described with respect to FIG. Therefore, in order to ionize a large amount of argon atoms 54, the heater 15 is turned on. This situation is illustrated in FIG. As a result, the ionization efficiency of the argon atoms 54 is maximized while the helium atoms 52 are hardly ionized. Thus, a parallel beam of argon ions 55 is generated at the tip 212 under the temperature and voltage source conditions provided in the situation shown in FIG.

  [0059] Of course, this principle can also be applied to combinations of other gases having different optimum release temperatures.

  [0060] Further, other suitable extraction voltages may be applied to provide a constant electric field in this example of the embodiment. For example, the extraction voltage can be selected to be at or near the extraction voltage that results in an electric field in which one of the gases has a maximum emission current at commonly used cooling temperatures. In another example, the extraction voltage is sufficient at a cooling temperature at which one of the gases is typically used and at a cooling temperature at which one of the gases is generally used, and at a cooling temperature at which the other is commonly used. A range between the extraction voltage with the emission current can be selected. Typically, while cooling at a commonly used cooling temperature, for example, an extraction voltage that provides an electric field to ionize one of the two gases (which has higher ionization energy). You can choose. In another exemplary embodiment, an electric field is provided to ionize one of the two gases (which has less ionization energy) while cooling at a commonly used cooling temperature. The extraction voltage to be selected can be selected. In any case, for example, ionization of the other of the two gases can be initiated by heating the emitter tip.

  [0061] In a further embodiment, the principles of chip temperature switching and extraction voltage switching can be combined for maximum efficiency. In some embodiments, more than two gases can be supplied, more than two chip temperatures can be provided, and optionally more than two extraction voltages can be provided, and / or optionally more gases. By adjusting the partial pressure of the gas, the preferentially emitted gas is selected. Thus, in some embodiments, switching between three or more different emitter tip temperatures, optionally switching between three or more different extraction voltages, and / or optionally between three or more different gases. It is possible to generate more than two different ion beams by switching.

  [0062] Thus, in one embodiment, a method of operating a focused ion beam device, wherein at least two different ion beams of a first gas and at least one second gas are at least two different emitter tips. A continuously generated method is provided by switching between temperatures and optionally switching between at least two different extraction voltages and / or between at least two of the first gas and at least the second gas. Is done. Each of the emitter tip temperature and extraction voltage results in ionization for at least one of the gases. In some embodiments, each of the emitter tip temperature and / or extraction voltage results in optimal (eg, maximum) ionization efficiency for at least one of the gases.

  For example, according to one example of an embodiment, referring to FIG. 4, a voltage may be supplied by a voltage source 72 between the emitter 13 and the extraction electrode 18. The heater 15 adjacent to the emitter tip 212 is controlled by a controller 172 that can also control the voltage source 72. In order to control the chip temperature, a temperature sensor (not shown) connected to the controller 172 can be provided, for example, on the emitter chip support. As a cooling unit, for example, a closed cycle He cryogenic cooler (not shown) is connected to the emitter tip support and is used to cool the emitter tip 13. According to some embodiments, the controller 172 can communicate with the controller 130 for the supply of the first and second gas inlets. The emitter comprises a shank 210 and a tip 212. In the embodiment shown in FIG. 4, a mixture of helium atoms 52 and argon atoms 54 represented by separate shapes can be supplied and adsorbed or deposited on the shank 210 of the emitter tip 13. As noted above, typically helium requires an electric field of about 44 V / nm for ionization, while argon requires an electric field of about 22 V / nm for ionization. For example, if a helium ion beam of helium ions 53 is to be formed, the voltage source 72 may apply an extraction voltage that provides an electric field, eg, about 44 V / nm or slightly higher, at least a portion of the surface of the chip. Adjust to add to position 212. Furthermore, the heater 15 is not operated so that a temperature of about 20 K, for example, is applied to the emitter tip 13. As shown in FIG. 4, helium atoms 52 and argon atoms 54 condense or deposit on the shank 210 and move toward the tip 212 by diffusion or drift. Since the temperature of the tip and the electric field at the emitter tip 13 coincide with the temperature and electric field at which helium emission is maximized, helium atoms are ionized while argon atoms 54 are hardly ionized. Thus, a parallel beam of helium ions 53 is generated under the voltage and temperature conditions described with respect to FIG. If a large amount of argon atoms 54 is to be ionized, the heater 15 is turned on to heat the emitter tip, for example to about 80K. In addition, the voltage source 72 is adjusted to apply an extraction voltage at the location of the chip 212 that results in an electric field on at least a portion of the surface of the chip, for example about 22 V / nm or slightly higher. The switching of the temperature of the emitter chip and the extraction voltage of the emitter chip can be performed substantially simultaneously. In this embodiment, when the temperature of the emitter tip and the extraction voltage of the emitter tip are switched, the ionization efficiency of the argon atoms 54 is maximized while the helium atoms 52 are hardly ionized. This situation is illustrated in FIG. Thus, a parallel beam of argon ions 55 is generated at the tip 212 under the temperature and voltage source conditions provided in the situation described with respect to FIG.

  [0064] FIG. 6 shows an embodiment of a further focused ion beam device 600 that can be combined with any other embodiments disclosed herein. The charged particle beam device comprises an emitter 12 having an emitter region, an optional housing / gun chamber 14, and an ion beam column 16. The electric field is supplied between the emitter tip of the emitter 12 and the extraction electrode 18. Gas ions present in the housing 14 are generated by a high electric field near the small curvature of the tip portion of the emitter tip (eg, a tip with a very sharp tip or supertip).

  [0065] According to one embodiment, a first gas inlet 110, a second gas inlet 112, and a third gas inlet 613 are provided. It is therefore possible to supply three different gases and / or mixtures of gases to the housing. For example, a light gas such as hydrogen or helium can be introduced by the first gas inlet 110 to observe the sample without damaging the sample. In another mode of operation, a second gas, such as argon, neon, xenon, or krypton, can be introduced through the second gas inlet 112 for sputtering of the sample. In yet another mode of operation, a third gas having different properties with respect to sputtering or sample modification can be used.

  [0066] According to further embodiments, hydrogen may be used for still further modes of operation when etching materials such as photoresist. The reducibility of hydrogen can be used for etching oxygen-containing materials. Nevertheless, it is also possible to use hydrogen in an imaging mode for multiple materials such as silicon and metal.

  [0067] According to still further embodiments, a fourth gas inlet can be provided. As a result, the fourth operation mode can be executed by introducing a conditioning gas such as oxygen around the emitter chip in the housing. According to this embodiment, oxygen can be used for conditioning the chip. In this further conditioning mode of operation, the emitter tip is shaped or reshaped, which can be aided by the introduction of oxygen. According to a still further embodiment, it is also possible to use a fourth or fifth gas for the operating mode of imaging and / or sample modification.

  [0068] Generally, in the embodiments described herein, at least two different gases (also referred to herein as ion beam generating gases) for generating one or more ion beams are contained in a housing. Can be introduced. According to the embodiments described herein, at least two different ion beam generating gases are introduced into the housing as a gas mixture, and the generated ion beam guided through the column of the focused ion beam device is emitted from the emitter. Select by changing the temperature of the tip and optionally changing the voltage between the emitter tip 13 and the extraction electrode or another electrode provided to adjust the electric field at the tip of the emitter tip It is possible.

  [0069] As noted above, light and heavy gases can be used as the ionogenic gas. According to a further embodiment, at least one further ionogenic gas can be introduced into the housing. As a result, an ion generating gas for etching, or an ion generating gas for a second sputtering option (eg, a first sputtering option with argon and a second sputtering option with neon or xenon) is introduced. Is possible. According to some embodiments, at least a third gas inlet is provided or a mixture of three gases is supplied. If two or more ion beam generating gases for sputtering or two or more ion beam generating gases for etching are used, a fourth, fifth, etc. gas inlet can be provided, or four Alternatively, a mixture of five or more gases can be supplied.

  [0070] Further, according to a further embodiment, it is possible to introduce a process gas in the form of the above-mentioned emitter tip conditioning gas (oxygen), carrier gas, purge gas, etc. Process gas is not used to generate an ion beam, but should be understood as a gas used to support the process.

  [0071] According to another embodiment that can be combined with any other embodiment described with respect to FIG. 6 and disclosed herein, a gas outlet 620 can further be provided. The gas outlet 620 can be connected to a vacuum system including a vacuum pump and / or a vacuum vessel. The exhaust of the housing 14 can be used to control the pressure in the housing to control process parameters for ion generation. Typically, the partial pressure of the gas to be ionized is controlled to be in the range of 10-6 to 10-2 mbar in the emitter region. According to another embodiment, the exhaust of the housing 14 can be used when switching between a first mode of operation and a further (second or third) mode of operation. Thereby, the gas used for the first mode of operation can be removed faster from the region of ion generation. As a result, switching between one operation mode and another operation mode can be performed faster, for example, within 5 seconds.

  [0072] In some embodiments that can be combined with other implementations, it is possible to provide a gas pressure gradient to the gun chamber. Thereby, the gas pressure is higher in the vicinity of the emitter and the emitter tip and becomes lower toward the extraction electrode. Therefore, a sufficient amount of gas can be supplied to the emitter tip, and the amount of gas that may hinder ion emission is reduced. According to various examples that can be combined with any of the embodiments described herein, the gas pressure gradient may reach 5e-3 mbar to 10e-6 mbar, typically 10e-3 mbar to It may reach 10e-4mbar.

  [0073] In FIG. 7A, a charged particle beam device 700 is shown. The charged particle beam device includes an emitter 12, a housing / gun chamber 14, and an ion beam column 16. The ions of the gas present in the housing 14 are generated by the high electric field of the biased emitter 12.

  [0074] According to one embodiment, a first gas inlet 110 and a second gas inlet 112 are provided. Further, a valve 718 is provided at the first gas inlet 110. Further, a valve 179 is provided at the second gas inlet 112. The valve is controlled by a controller configured to switch between the introduction of the first gas into the housing 14 and the introduction of the second gas into the housing.

[0075] According to one embodiment, valves 718 and 719 are located near the outlet opening of the gas inlet. As a result, for the second or third mode of operation, the amount of gas remaining from the previous mode of operation that must be removed is reduced. When one of the valves is closed, the volume in which the gas in the previous mode of operation is still present is minimized if the valve is located near the outlet opening of the gas inlet. The wasteful volume of the gas inlet can be set within a range of 1 cm ³ or less, for example. Typically, microvalves can be used to reduce wasted volume. As used herein, wasted volume can be defined as a portion of a passageway where a substance or gas that can contaminate subsequent fluids may remain. During the switch, the previous gas can contaminate the subsequent gas.

  [0076] According to other embodiments mentioned with respect to FIG. 7A, a gas outlet 620 may further be provided. The gas outlet 620 can be connected to a vacuum system including a vacuum pump or vacuum vessel. As described above, the exhaust of the housing 14 can be used to control the pressure in the housing. It is also possible to use the exhaust of the housing 14 to exhaust the housing when switching between the first operating mode and a further (second or third) operating mode. Thereby, the gas used for the first operation mode can be more quickly removed from the ion generation region.

  In FIG. 7B, the charged particle beam device comprises an emitter 12, a housing / gun chamber 14, and an ion beam column 16. The ions of the gas present in the housing 14 are generated by the high electric field of the biased emitter 12. The gas can be introduced into the housing according to any embodiment described herein.

  [0078] According to another embodiment, a valve 728 is provided at the gas outlet 620, for example as described with respect to FIG. 7B. The gas outlet valve 728 can be closed to provide a low pressure on the opposite side of the valve housing 14. As a result, when switching between the first operating mode and the further operating mode, the valve is opened in order to more quickly remove the gas in the housing that must be removed in switching between the operating modes, It is possible to use a low pressure on the opposite side.

  [0079] According to yet another embodiment, this aspect can be combined with a vacuum vessel 822 as shown in the focused ion beam device 800 of FIG. In FIG. 8, a charged particle beam device 800 is illustrated. The charged particle beam device includes an emitter 12, a housing / gun chamber 14, and an ion beam column 16. The ions of the gas present in the housing 14 are generated by the high electric field of the biased emitter 12. Further, a valve 718 is provided at the first gas inlet 110. Further, a valve 719 is provided at the second gas inlet 112. The valve is controlled by a controller configured to switch between the introduction of the first gas into the housing 14 and the introduction of the second gas into the housing. When one valve is closed, the volume in which there is still gas in the previous operating mode that needs to be removed for switching to another operating mode is located near the outlet opening of the gas inlet. If so, it can be minimized.

  [0080] In FIG. 8, the conduit of the gas outlet 620 is connected to a vacuum pump. A vacuum pump evacuates the vacuum vessel 822. As a result, the volume of low pressure becomes larger. As a result of the additional volume of the container 822, the volume of the housing 14 can be evacuated faster when the valve 728 is opened. The reduction in time for evacuation of the housing allows for a quicker switch between the two operating modes.

  [0081] FIG. 9 shows a focused ion beam device 900. FIG. The charged particle beam device 900 includes an emitter 12, a housing / gun chamber 14, and an ion beam column 16. The ions of the gas present in the housing 14 are generated by the high electric field of the biased emitter 12.

  [0082] According to one embodiment, a first gas inlet 110 having a conduit and a second gas inlet 112 having a conduit are provided. Further, the valve 818 is provided at the first gas inlet 110. Further, the valve 819 is provided at the second gas inlet 112. The valve is controlled by a controller configured to switch between the introduction of the first gas into the housing 14 and the introduction of the second gas into the housing. According to one embodiment, valves 818 and 819 are located near the outlet opening of the gas inlet. As a result, because of the second or third mode of operation, the amount of gas remaining from the previous mode of operation that must be removed is reduced.

  [0083] In FIG. 9, valves 818 and 819 are two-way valves. Further connections of these valves are connected to vacuum vessels 822 and 823, respectively. The vacuum containers 822 and 823 are exhausted by a vacuum pump or the like. As a result, the switching behavior between the first operation mode and the further operation mode can be improved. For example, when the valve 818 is closed, on the other hand, the supply of the first gas introduced by the first gas inlet 110 is stopped. On the other hand, the vacuum vessel 822 is connected to the outlet opening portion of the gas inlet. As a result, the gas remaining in the exit opening portion of the gas introduction port is removed from the exit opening portion, and the housing 14 is exhausted. At the same time or after the event, the valve 819 of the second gas inlet 112 can be opened, and the gas introduced through the second gas inlet can be supplied to the housing 14.

  [0084] According to another embodiment, valves 818 and 819 may be connected to a common vacuum vessel by respective conduits.

  [0085] According to one embodiment, a further gas outlet 620 comprising a valve 728 is provided, as shown in FIG. The gas outlet valve 728 can be closed to provide a low pressure on the opposite side of the valve housing 14. As a result, when switching between the first operating mode and the further operating mode, the valve is opened to more quickly remove the gas in the housing that needs to be removed for switching between the operating modes. Thus, it is possible to use a low pressure.

  [0086] According to another embodiment, the gas outlet 620 can be omitted. In that case, the housing 14 can be evacuated through one of the valves 818 and 819. As a result, when one valve is in a position to introduce gas into the emitter 12 region, the other valve is in a position to evacuate the housing 14 via a vacuum vessel connected to the corresponding valve. is there. In general, the use of a two-way valve to shut off the gas flow closes the connection between the gas and the emitter chamber, ie the housing, and opens the connection between the emitter chamber and the vacuum vessel or vacuum pump. It is. As a result, a rapid drop in gas pressure within the emitter is provided.

  [0087] In addition to the modes of operation described above, a heavy gas ion beam can be used for material analysis. As a result, a detector suitable for the secondary ion mass spectrometer SIMS 722 (see, eg, FIGS. 1A and 1B) is provided. A detector detects and analyzes the ions of the sample produced by sputtering. During sputtering, the sample emits particles, some of which are ions themselves. These secondary ions are measured using a mass spectrometer to determine the quantitative elemental or isotopic composition of the surface.

  [0088] According to one embodiment, sputtering is achieved by an ion beam emitted by emitter 12, as illustrated in the previous figures. According to another embodiment, an additional flood electron source 732 (see, eg, FIGS. 1A and 1B) can be provided. As a result, the number of ionized secondary particles emitted from the sample when the ion beam collides from the emitter 12 can be increased. Increasing the number of ionized secondary particles improves the detection sensitivity of the detector.

  [0089] As described above, a single column charged particle beam device in the form of a focused ion beam device that enables high resolution imaging and sample modification can be provided. Thus, cost savings can be achieved in view of the fact that only one column is used.

  [0090] According to one embodiment, which can be combined with any other embodiment disclosed herein, to accommodate a gas field ion source emitter having an emitter tip and an emitter region for generating ions. An ion beam column configured; heating means configured to heat the emitter tip; and one or more gas inlets configured to introduce a first gas and at least a second gas into the emitter region. Switching between a first emitter tip temperature and at least a second emitter tip temperature to produce an ion beam of ions of a first gas ion or of at least a second gas ion And a controller configured to provide a focused ion beam device.

  [0091] According to one embodiment that can be combined with any other embodiment disclosed herein, the heating means comprises a resistance heater, an electromagnetic heater, an induction heater, a radiant heater, an IR heater, a particle source, and At least one element selected from the group consisting of lasers.

  [0092] According to one embodiment that can be combined with any other embodiment disclosed herein, the heating means is disposed adjacent to the emitter tip.

  [0093] According to one embodiment that can be combined with any other embodiment disclosed herein, the emitter tip is provided on a support comprising a filament and a filament base, and the heating means comprises an emitter tip, It is configured to heat at least one element selected from the group consisting of a filament and a filament base.

  [0094] One embodiment that can be combined with any other embodiment disclosed herein includes an electrode configured to extract ions from a gas field ion source emitter, and the electrode and the gas field ion source emitter. And a voltage source configured to supply a voltage therebetween.

  [0095] According to one embodiment, which can be combined with any other embodiment disclosed herein, the controller comprises an ion beam of ions of a first gas or ions of at least one second gas. It is further configured to switch between a first voltage of the voltage source and at least one second voltage to generate the ion beam.

  [0096] According to one embodiment that can be combined with any other embodiment disclosed herein, the first gas is composed of a gas having an atomic weight of less than 10 g / mol, hydrogen, and helium. And at least one second gas is at least one selected from the group consisting of a heavy gas having an atomic weight of 10 g / mol or more and a reactive gas. Is one gas.

[0097] According to one embodiment that can be combined with any other embodiment disclosed herein, the heavy gas is selected from the group consisting of physical sputtering gas, argon, neon, and krypton. At least one gas, and the reactive gas is at least one gas selected from the group consisting of oxygen, hydrogen, and CO ₂ .

  [0098] One embodiment that can be combined with any other embodiment disclosed herein further comprises a gas outlet connected to a vacuum system configured to evacuate at least the emitter region.

  [0099] One embodiment that can be combined with any other embodiment disclosed herein is a first valve provided at a first gas inlet of a gas inlet, and a gas inlet. At least one second valve provided at at least one second gas inlet, the first valve and at least one second valve comprising the first gas and at least one Controlled to adjust the partial pressure of the two second gases.

  [0100] In one embodiment that can be combined with any other embodiment disclosed herein, a method of operating a focused ion beam device comprising an emitter tip in an emitter region where ions are generated. Biasing a potential to provide an extraction voltage for emitting an ion beam of at least one of the first gas and the at least one second gas to the emitter, wherein: Heating to an emitter tip temperature and emitting an ion beam of a first gas; heating to at least one second emitter tip temperature and at least one ion beam of at least one second gas; Irradiating the method.

  [0101] According to one embodiment that can be combined with any other embodiment disclosed herein, the emitter is a potential for providing an extraction voltage for emitting an ion beam of a first gas. Biased towards.

  [0102] One embodiment that can be combined with any other embodiment disclosed herein is a first that provides an extraction voltage for a first gas in the step of heating to a first emitter tip temperature. Biasing to a potential of.

  [0103] One embodiment that can be combined with any other embodiment disclosed herein is a first that provides an extraction voltage of a first gas in the step of heating to a first emitter tip temperature. Biasing to at least one second potential for supplying at least one second gas extraction voltage in the step of biasing to a potential of at least one second emitter tip and heating to at least one second emitter tip temperature. Performing.

  [0104] One embodiment that can be combined with any other embodiment disclosed herein is the extraction of at least one second gas in the step of heating to at least one second emitter tip temperature. Biasing to at least one second potential to supply a voltage.

  [0105] In one embodiment that can be combined with any other embodiment disclosed herein, the first gas is a light gas and the at least one second gas is a heavy inert gas. And an ion beam of the first gas is generated for the observation mode, and an ion beam of the heavy inert gas is generated for the sputtering mode. The ion beam of the reactive gas is generated for the reaction mode.

  [0106] One embodiment, which can be combined with any other embodiment disclosed herein, is to scan an ion beam generated from a first gas over a sample in an observation mode to observe the sample. For this purpose, the method includes a step of detecting fine particles emitted from the sample when the ion beam generated from the first gas collides.

  [0107] One embodiment, which can be combined with any other embodiment disclosed herein, is to modify the sample when at least one second gas is introduced into the emitter region in a modified mode. Reforming.

  [0108] According to one embodiment that can be combined with any other embodiment disclosed herein, the modifying step comprises at least one step selected from the group consisting of sputtering and etching. Including.

  [0109] According to one embodiment that can be combined with any other embodiment disclosed herein, the first gas is a light gas, a gas having an atomic weight of less than 10 g / mol, hydrogen, and helium. At least one gas selected from the group consisting of:

[0110] According to one embodiment that can be combined with any other embodiment disclosed herein, the at least one second gas comprises a heavy gas, a physical sputtering gas, an atomic weight of 10 g / mol or more. Or at least one gas selected from the group consisting of argon, neon, krypton, reaction gas, process gas, oxygen, hydrogen, and CO ₂ .

  [0111] One embodiment that can be combined with any other embodiment disclosed herein introduces a process gas, which may be oxygen, into the emitter region, optionally with further heating to the tip temperature. Introducing a further heavy gas having an atomic weight of 10 g / mol or more into the emitter region, optionally heating to a further tip temperature, and introducing hydrogen into the emitter region in an etching mode of operation, optionally further Heating to the tip temperature further comprises at least one step selected from the group consisting of, and separating the ions of the first gas from the ions of the at least one second gas.

  [0112] According to further embodiments that can be combined with any other embodiments disclosed herein, the process gas is oxygen.

  [0113] According to further embodiments that can be combined with any other embodiments disclosed herein, an emitter tip and an emitter for generating ions of a first gas and at least one second gas An ion beam column comprising a housing for containing an emitter having a region, and means for switching between a first emitter tip temperature and at least one second emitter tip temperature, The focused ion beam device is provided in which one gas is selected from the group consisting of hydrogen and helium, and at least one second gas has an atomic weight of 10 g / mol or more.

  [0114] According to one embodiment that can be combined with any other embodiment disclosed herein, the first valve comprises a first gas supply conduit to a gas source of the first gas, A first gas introduction conduit for introducing a first gas into the chamber, and a first exhaust conduit for connection to at least one vacuum vessel, the second valve comprising: A second gas supply conduit to a gas source of gas, a second gas introduction conduit for introducing a second gas into the chamber, and a second exhaust conduit for connection to at least one vacuum vessel Have.

  [0115] According to one embodiment that can be combined with any other embodiment disclosed herein, the first gas inlet and the second gas inlet are for supply to the housing. Supply gas to a common gas inlet.

  [0116] According to one embodiment that can be combined with any other embodiment disclosed herein, a vacuum system includes a vacuum vessel.

  [0117] One embodiment that can be combined with any other embodiment disclosed herein is an ion beam column, a scanning deflector configured to scan an ion beam over a sample, an ion A detector provided in the beam column and configured to detect time-resolved particles emitted from the sample upon collision of the ion beam, and a controller connected to the scanning deflector and the detector are further provided.

  [0118] According to one embodiment that can be combined with any other embodiment disclosed herein, the time-resolved measurement is configured for a time resolution of 2 μs or less than 2 μs.

  [0119] According to one embodiment that can be combined with any other embodiment disclosed herein, a housing is provided in the gun chamber of the ion beam column.

[0120] According to one embodiment that can be combined with any other embodiment disclosed herein, the housing has a volume of 5 cm ³ or less.

  [0121] One embodiment that can be combined with any other embodiment disclosed herein further comprises a mass spectrometer for identifying ions or ionized particles emitted from the sample.

  [0122] One embodiment that can be combined with any other embodiment disclosed herein further comprises a flood electron gun provided in a region adjacent to the sample region.

  [0123] One embodiment that can be combined with any other embodiment disclosed herein further comprises a third gas inlet for introducing at least a third gas into the housing.

  [0124] One embodiment that can be combined with any other embodiment disclosed herein further comprises at least a third valve provided at least in the third gas inlet and controlled by a controller.

  [0125] According to one embodiment that can be combined with any other embodiment disclosed herein, the first gas is a light gas selected from the group consisting of hydrogen and helium; The second gas is a heavy gas selected from the group consisting of argon, neon, krypton, and combinations thereof.

  [0126] One embodiment that can be combined with any other embodiment disclosed herein further comprises a mass separator for separating ions from a first gas from ions from a second gas. Prepare.

  [0127] One embodiment that can be combined with any other embodiment disclosed herein is a first extraction for emitting a light gas ion beam to the emitter of the emitter region where ions are generated. Biasing a first potential for supplying a voltage, and a second for supplying a second extraction voltage for emitting a heavy gas ion beam to the emitter of the emitter region where the ions are generated. Biasing the potential, wherein the light gas is selected from the group consisting of hydrogen and helium, and the heavy gas has an atomic weight of 10 g / mol or more.

  [0128] One embodiment that can be combined with any other embodiment disclosed herein further comprises evacuating the enclosure surrounding the emitter region.

  [0129] According to one embodiment that can be combined with any other embodiment disclosed herein, the switching includes controlling the power supply of the extraction voltage.

  [0130] One embodiment, which can be combined with any other embodiment disclosed herein, scans a sample with an ion beam generated from a light ion beam generating gas in an observation mode and observes the sample. For detecting particulates emitted from the sample upon impact of the ion beam from the light ion beam generating gas, and in the modification mode, when the heavy ion beam generating gas is introduced into the emitter region, Further comprising the step of modifying.

  [0131] One embodiment that can be combined with any other embodiment disclosed herein provides for mass detection of ionized particles emitted from a sample when a heavy ion beam generating gas is introduced into the emitter region. The method further includes performing.

  [0132] One embodiment that can be combined with any other embodiment disclosed herein includes ionizing particles emitted from a sample when a heavy ion beam generating gas is introduced into the emitter region. In addition.

  [0133] In one embodiment that can be combined with any other embodiment disclosed herein, a method of operating a focused ion beam device, comprising: a first gas and at least one second gas; The at least two different ion beams switch between at least two different emitter tip temperatures, optionally with respect to an emitter tip temperature and an extraction voltage, each resulting in ionization of at least one of the gases, and optionally at least two different extraction A continuously generated method is provided by switching between voltages and / or switching between at least two of the first gas and at least the second gas.

  [0134] In a further embodiment that can be combined with any other embodiment disclosed herein, a method of operating a focused ion beam device comprising a first gas and at least one second gas A method is provided in which the at least two different ion beams are successively generated by switching between at least two different emitter tip temperatures, each resulting in ionization of at least one of the gases.

  [0135] In one embodiment that can be combined with any other embodiment disclosed herein, at least two different ion beams of a first gas and at least one second gas are included in the gas. Further switching between at least two different extraction voltages and / or between at least two of the first gas and at least the second gas, with respect to the emitter tip temperature and the extraction voltage that respectively cause at least one ionization of Are continuously generated.

  [0136] The description herein uses examples to disclose the invention, such examples including the best mode, and further to enable any person skilled in the art to make and use the invention. Is possible. While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims. Will. In particular, features that are not mutually exclusive of the above-described embodiments can be combined with each other. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other embodiments are also within the scope of the appended claims.

  [0137] While the above is directed to some embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope of the invention. The technical scope of the present invention is defined by the following claims.

DESCRIPTION OF SYMBOLS 10 ... Emitter holder, 12 ... Emitter, 13 ... Emitter tip, 14 ... Housing / chamber, 15 ... Heater, 16 ... Ion beam column, 17 ... Gun chamber, 18 ... Extraction electrode, 20 ... Lens, 22 ... Detector, 24 ... Sample, 26 ... Scanning deflector, 30 ... Cooling unit, 52 ... Helium atom, 53 ... Helium ion, 54 ... Argon atom, 55 ... Argon ion, 72 ... Power source, 100, 600, 800, 900 ... Focused ion beam Apparatus, 102 ... Optical access, 110 ... First gas inlet, 111, 113, 121, 130, 140, 172, 472 ... Controller, 112 ... Second gas inlet, 120 ... Gas outlet, 210 ... Shank , 212 ... chip, 300a, 300b ... focused ion beam column, 310 ... common gas inlet, 613 ... first Gas inlet, 620 ... gas outlet, 700 ... charged particle beam device, 718, 719, 728 ... valve, 722 ... mass spectrometer, 732 ... electron source, 742 ... mass separator, 822, 922, 923 ... vacuum container.

Claims (16)

An ion beam column configured to accommodate an emitter tip (13) for generating ions and a gas field ion source emitter having an emitter region;
Heating means (15) configured to heat the emitter tip (13);
One or more gas inlets (110, 112; 613) configured to introduce a first gas and at least one second gas into the emitter region;
Between a first emitter tip temperature and at least one second emitter tip temperature to generate an ion beam of ions of the first gas or an ion beam of ions of the at least one second gas. A controller (172) configured to perform the switching;
A focused ion beam apparatus.   The emitter tip is provided on a support portion including a filament and a filament base, and the heating means (15) includes at least one element selected from the group consisting of the emitter tip, the filament, and the filament base. The focused ion beam device according to claim 1, which is configured to be heated. An electrode (18) configured to extract ions from the gas field ion source emitter;
A voltage source (72) configured to supply a voltage between the electrode and the gas field ion source emitter;
And / or the controller (172) is configured to generate an ion beam of ions of the first gas or an ion beam of ions of the at least one second gas. The focused ion beam device according to claim 1 or 2, further configured to switch between a voltage and at least one second voltage. The first gas is a light gas that is at least one gas selected from the group consisting of a gas having an atomic weight of less than 10 g / mol, hydrogen, and helium;
The at least one second gas is at least one gas selected from the group consisting of a heavy gas having an atomic weight of 10 g / mol or more and a reactive gas. Focused ion beam device. The heavy gas is at least one gas selected from the group consisting of physical sputtering gas, argon, neon, and krypton, and / or the reaction gas is composed of oxygen, hydrogen, and CO ₂ . The focused ion beam device according to claim 1, wherein the focused ion beam device is at least one gas selected from a group.   Objective lens (20) configured to focus the ion beam generated from the first gas or the at least one second gas, and a vacuum system configured to evacuate at least the emitter region The focused ion beam device according to any one of claims 1 to 5, further comprising at least one component selected from the group consisting of a gas outlet (120; 620) connected to the gas outlet. The first valve (718) provided in the first gas inlet (110) of the gas inlets and the second gas inlet (112) of at least one of the gas inlets. And at least one second valve (719) provided,
7. The first valve and the at least one second valve are controlled to regulate partial pressures of the first gas and the at least one second gas, respectively. The focused ion beam apparatus according to Item. A method of operating a focused ion beam device comprising:
Extraction voltage for emitting an ion beam of at least one of a first gas and at least one second gas to an emitter having an emitter tip (13) in the emitter region where ions are generated Biasing a potential to supply
Heating to a first emitter tip temperature and emitting an ion beam of the first gas;
Heating to at least one second emitter tip temperature and emitting at least one ion beam of said at least one second gas;
A method comprising: In the step of heating to the first emitter tip temperature, biasing a first potential for supplying an extraction voltage of the first gas, and / or to the at least one second emitter tip temperature In the step of heating, biasing at least one second potential for supplying an extraction voltage of the at least one second gas;
A method of operating a focused ion beam device according to claim 8. The first gas is a light gas and the at least one second gas is at least one gas selected from the group consisting of a heavy inert gas and a reactive gas;
The ion beam of the first gas is generated for an observation mode;
The ion beam of heavy inert gas is generated for sputtering mode,
The method of operating a focused ion beam apparatus according to claim 8 or 9, wherein an ion beam of the reaction gas is generated for a reaction mode. In the observation mode, an ion beam generated from the first gas is scanned on the sample (24), and the sample is collided with the ion beam generated from the first gas for observation of the sample. Detecting particles released from the
Modifying the sample when the at least one second gas is introduced into the emitter region in a modification mode;
A method of operating a focused ion beam device according to claim 8 or 10 further comprising: The modifying step includes at least one process selected from the group consisting of sputtering, reaction, and etching, and / or the first gas has a light gas and an atomic weight of less than 10 g / mol. At least one gas selected from the group consisting of gas, hydrogen, and helium, and / or the at least one second gas has a heavy gas, a physical sputtering gas, an atomic weight of 10 g / mol or more gas, argon, neon, krypton, reactive gas, process gas, oxygen, hydrogen, and focusing as claimed in any one of claims 8 to 11 is at least one gas selected from the group consisting of CO ₂ A method of operating an ion beam device. Introducing a process gas, which may be oxygen, into the emitter region and optionally heating to a further emitter tip temperature;
Introducing a further heavy gas having an atomic weight of 10 g / mol or more into the emitter region and optionally heating to a further emitter tip temperature;
Introducing hydrogen into the emitter region in an etching mode of operation, optionally heating to a further emitter tip temperature;
At least one step selected from the group consisting of:
Separating the ions of the first gas from the ions of the at least one second gas;
A method of operating a focused ion beam device according to claim 8, further comprising: A method of operating a focused ion beam device comprising:
The at least two different ion beams of the first gas and the at least one second gas are continuous by switching between at least two different emitter tip temperatures, each resulting in ionization of at least one of the gases. Generated method.   The at least two different ion beams of the first gas and the at least one second gas are at least two different extraction voltages with respect to an emitter tip temperature and extraction voltage that respectively result in ionization of at least one of the gases. 15. The method of claim 14, wherein the method is continuously generated by further switching between and / or between at least two of the first gas and the at least second gas. An emitter tip (13) for generating ions of a first gas and at least one second gas, an ion beam column (16) containing an emitter having an emitter region, and a first emitter tip temperature; Means for switching between at least one second emitter tip temperature;
The focused ion beam device, wherein the first gas is selected from the group consisting of hydrogen and helium, and the at least one second gas has an atomic weight of 10 g / mol or more.

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