阅读说明：本技术 粒子射束装置和复合射束装置 (Particle beam device and composite beam device ) 是由 永原幸儿 间所祐一 于 2021-03-16 设计创作，主要内容包括：本发明提供粒子射束装置和复合射束装置,该粒子射束装置能够选择性地且适当地切换带电粒子射束和中性粒子射束。粒子射束镜筒(19)具备离子源(41)、聚光镜(52)、电荷交换栅极(55)和物镜(56)。离子源(41)产生离子。聚光镜(52)通过切换离子射束的聚焦而切换离子射束和中性的射束作为照射至试样(S)的粒子射束。电荷交换栅极(55)通过将离子射束的至少一部分中性化而转换成中性粒子射束。物镜(56)配置于电荷交换栅极(55)的下游侧。在对试样(S)照射中性粒子射束作为粒子射束的情况下,物镜(56)减少朝向试样(S)的离子射束。(The invention provides a particle beam device and a composite beam device, which can selectively and appropriately switch a charged particle beam and a neutral particle beam. A particle beam column (19) is provided with an ion source (41), a condenser lens (52), a charge exchange grid (55), and an objective lens (56). An ion source (41) generates ions. The condenser lens (52) switches the ion beam and the neutral beam as the particle beam to be irradiated to the sample (S) by switching the focus of the ion beam. The charge exchange grid (55) converts at least a portion of the ion beam into a neutral particle beam by neutralizing the beam. The objective lens (56) is disposed downstream of the charge exchange grid (55). When a neutral particle beam is irradiated as a particle beam on a sample (S), an objective lens (56) reduces the ion beam directed toward the sample (S).)

1. A particle beam apparatus, comprising:

a particle beam column that irradiates a sample with a particle beam;

a charged particle source that generates charged particles within the particle beam column;

a conversion unit that neutralizes at least a part of the beam of charged particles generated from the charged particle source in the particle beam column, and converts the neutralized beam into a beam of neutral particles;

a switching unit that switches the beam of the charged particles and the beam of the neutral particles as the particle beam in the particle beam column; and

a reducing section that reduces the beam of the charged particles toward the sample on a downstream side of the converting section.

2. The particle beam apparatus of claim 1,

the switching unit includes an electrostatic lens that switches the beam of charged particles and the beam of neutral particles as the particle beam by a change in lens intensity associated with a degree of focusing of the beam of charged particles.

3. The particle beam apparatus of claim 1 or 2,

the switching unit includes at least one deflector that switches the charged particle beam and the neutral particle beam as the particle beam by deflecting the charged particle beam.

4. The particle beam apparatus of claim 3,

the at least one deflector includes an upstream deflector that deflects the beam of charged particles at a position upstream of the converter, thereby guiding or deflecting the beam of charged particles to or from the converter.

5. The particle beam apparatus of any of claims 1-4,

the reducing unit includes an objective lens to which a voltage is applied so as to decelerate and shield the beam of the charged particles at a position downstream of the converting unit.

6. A particle beam apparatus as claimed in any one of claims 1 to 5,

the particle beam device includes a shielding unit that shields the beam of the charged particles at a position upstream of the conversion unit in the particle beam column.

7. The particle beam apparatus of any of claims 1 to 6,

the particle beam apparatus includes an accelerating electrode for accelerating the beam of the charged particle in the particle beam column.

8. A composite beam device, characterized in that,

the composite beam apparatus includes the particle beam apparatus according to any one of claims 1 to 7 and a detector for detecting secondary charged particles generated from the sample by irradiation of the beam of charged particles.

9. The composite beam apparatus of claim 8,

the composite beam device includes an electron beam column for irradiating the sample with an electron beam.

10. The composite beam apparatus of claim 8 or 9,

the composite beam apparatus includes a focused ion beam column for irradiating the sample with a focused ion beam.

Technical Field

The invention relates to a particle beam device and a composite beam device.

Background

Conventionally, local processing on a micrometer level has been performed using a Focused Ion Beam (FIB) apparatus for, for example, a failure analysis of a semiconductor. For example, a charged particle beam apparatus including an FIB apparatus and a Scanning Electron Microscope (SEM) can perform observation using a secondary Electron image of an irradiation target such as a sample and sputtering using a high-energy ion beam.

However, the high-energy ions damage the surface of the sample, which may hinder observation. In order to solve such a problem, a dedicated processing apparatus or the like for removing surface damage by an ion beam of a rare gas having low energy is known as an FIB apparatus capable of operating at a low acceleration voltage. In the case of a low-energy ion beam, the beam is less focused than a high-energy ion beam, and thus it is difficult to observe the state of a processed region by a secondary electron image in the middle. Therefore, for example, if a process of gradually optimizing the finish state of the sample by repeating the exchange of the sample between the processing apparatus using the ion beam and the electron microscope is required, there arises a problem that the number of complicated processes increases.

Conventionally, a method of processing a nanodevice that suppresses generation of surface defects by using a neutral particle beam is known (for example, see non-patent document 1).

Conventionally, there is known a composite beam apparatus including a focused ion beam column, an Electron beam column, and a neutral particle beam column, in which a sample is processed by a focused ion beam, and then a surface of the sample is finished by the neutral particle beam while observing an sem (scanning Electron microscope) image obtained by the Electron beam (see, for example, patent document 1).

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2018-45811

Non-patent document

Non-patent document 1: hanchuan Chengni's second book, "atomic layer level surface defect suppression and surface chemical reaction control based on neutral particle beam process", applied physics, Vol.83, No. 11, 2014, pp894-899

Disclosure of Invention

Problems to be solved by the invention

However, the neutral particle beam column of the composite beam apparatus generates a neutral particle beam from an ion beam by a neutralization mechanism provided downstream of an objective lens for focusing the ion beam on a sample. However, in the case of the neutralization mechanism provided downstream of the objective lens, in a mode of irradiating the neutral particle beam to the sample, there is a possibility that the ion beam not converted into the neutral particle beam is irradiated to the sample.

The invention aims to provide a particle beam device and a composite beam device capable of selectively and appropriately switching a charged particle beam and a neutral particle beam.

Means for solving the problems

In order to solve the above problem, a particle beam apparatus according to the present invention includes: a particle beam column that irradiates a sample with a particle beam; a charged particle source that generates charged particles in the particle beam column; a conversion unit that converts the charged particle beam generated from the charged particle source in the particle beam column into a neutral particle beam by neutralizing at least a part of the neutral particle beam; a switching unit that switches the beam of the charged particles and the beam of the neutral particles as the particle beam in the particle beam column; and a reducing unit that reduces the beam of the charged particles toward the sample on a downstream side of the converting unit.

In the above configuration, the switching unit may include an electrostatic lens that switches the beam of charged particles and the beam of neutral particles as the particle beam by a change in lens intensity associated with a degree of focusing of the beam of charged particles.

In the above configuration, the switching unit may include at least one deflector that switches the beam of charged particles and the beam of neutral particles as the particle beam by deflecting the beam of charged particles.

In the above configuration, the at least one deflector may include an upstream deflector that deflects the beam of charged particles at a position upstream of the converting unit, thereby guiding or deflecting the beam of charged particles to or from the converting unit.

In the above configuration, the reducing unit may include an objective lens to which a voltage is applied so as to decelerate and shield the beam of the charged particles at a position downstream of the converting unit.

In the above configuration, the particle beam column may include a shielding portion that shields the beam of the charged particles at a position upstream of the conversion portion in the particle beam column.

In the above configuration, the particle beam column may include an acceleration electrode for accelerating the beam of the charged particles.

A composite beam device according to the present invention includes the particle beam device described above and a detector that detects secondary charged particles generated from the sample by irradiation of the beam of charged particles.

In the above configuration, an electron beam column for irradiating the sample with an electron beam may be provided.

In the above configuration, the ion source may be a focused ion beam column that irradiates the sample with a focused ion beam.

Effects of the invention

According to the present invention, by providing the reducing unit that reduces the beam of the charged particles on the downstream side of the converting unit that converts the beam of the charged particles into the beam of the neutral particles, it is possible to suppress irradiation of the sample with the beam of the charged particles that is not neutralized when the sample is irradiated with the beam of the neutral particles, and it is possible to selectively and appropriately switch between the beam of the charged particles and the beam of the neutral particles.

Drawings

Fig. 1 is a diagram showing a configuration of a composite beam device according to an embodiment of the present invention.

Fig. 2 is a diagram schematically showing the configuration of a particle beam apparatus according to an embodiment of the present invention.

Fig. 3 is a diagram schematically showing the configuration of a charge exchange gate of a particle beam apparatus according to an embodiment of the present invention.

Fig. 4 is a diagram schematically showing an example of a processing process by the composite beam apparatus according to the embodiment of the present invention.

Fig. 5 is a diagram schematically showing another example of a processing process by the composite beam apparatus according to the embodiment of the present invention.

Fig. 6 is a diagram schematically showing the configuration of the charge exchange gate in modification 1 of the embodiment of the present invention.

Fig. 7 is a diagram schematically showing the configuration of the charge exchange gate in modification 2 of the embodiment of the present invention.

Fig. 8 is a diagram schematically showing the configuration of a particle beam apparatus according to modification 3 of the embodiment of the present invention.

Fig. 9 is a diagram schematically showing the configuration of a particle beam apparatus according to variation 4 of the embodiment of the present invention.

Fig. 10 is a diagram schematically showing a configuration of an electron confining electrode of a particle beam apparatus according to variation 4 of the embodiment of the present invention.

Fig. 11 is a diagram schematically showing a configuration of an electron confining electrode of a particle beam apparatus according to variation 5 of the embodiment of the present invention.

Fig. 12 is a diagram schematically showing the configuration of a particle beam apparatus according to variation 6 of the embodiment of the present invention.

Fig. 13 is a diagram schematically showing the configuration of the charge exchange gate of the particle beam apparatus according to variation 6 of the embodiment of the present invention.

Fig. 14 is a diagram schematically showing the configuration of a particle beam apparatus according to modification 7 of the embodiment of the present invention.

Detailed Description

Hereinafter, a composite beam apparatus 10 including the particle beam apparatus 1 according to the embodiment of the present invention will be described with reference to the drawings.

(Compound beam device)

Fig. 1 is a diagram showing a configuration of a composite beam apparatus 10 according to an embodiment.

The composite beam apparatus 10 includes a sample chamber 11, a sample holder 12, a sample stage 13, an electron beam column 15, a focused ion beam column 17, and a particle beam column 19, which are fixed to the sample chamber 11.

The composite beam apparatus 10 includes, for example, a secondary charged particle detector 21 as a detector fixed to the sample chamber 11. The composite beam apparatus 10 includes a gas supply unit 23 that supplies gas to the surface of the sample S. The composite beam apparatus 10 includes a control device 25 that collectively controls the operation of the composite beam apparatus 10 outside the sample chamber 11, and an input device 27 and a display device 29 that are connected to the control device 25.

Note that, hereinafter, each axial direction of the X axis, the Y axis, and the Z axis orthogonal to each other in the 3-dimensional space is a direction parallel to each axis. For example, the Z-axis is parallel to the vertical direction (e.g., vertical direction) of the composite beam device 10. The X-axis direction and the Y-axis direction are parallel to a reference plane (e.g., a horizontal plane) orthogonal to the up-down direction of the composite beam apparatus 10.

The sample chamber 11 is formed of a pressure-resistant case having an airtight structure capable of maintaining a desired reduced pressure state. The sample chamber 11 can be evacuated by an evacuation device (not shown) until the inside is brought into a desired reduced pressure state.

The sample holder 12 holds the sample S.

The sample stage 13 is disposed inside the sample chamber 11. Sample stage 13 includes a stage 31 that supports sample holder 12, and a stage drive mechanism 33 that three-dimensionally translates and rotates stage 31 integrally with sample holder 12.

The stage drive mechanism 33 translates the stage 31 along each of the X, Y, and Z axes, for example. The stage drive mechanism 33 rotates the stage 31 at an appropriate angle around each of a predetermined rotation axis and a tilt axis, for example. The rotation axis is set to be opposed to the stage 31, for example, and when the stage 31 is at a predetermined reference position around the axis of the tilt axis (T axis), the rotation axis is parallel to the vertical direction of the composite beam device 10. The tilt axis is, for example, parallel to a direction orthogonal to the up-down direction of the composite beam device 10. The stage drive mechanism 33 rotates the stage 31 eccentrically (eutric) around each of the rotation axis and the tilt axis, for example. Stage drive mechanism 33 is controlled by a control signal output from control device 25 in accordance with the operation mode of composite beam device 10 and the like.

The electron beam column 15 irradiates an irradiation target within a predetermined irradiation region inside the sample chamber 11 with an Electron Beam (EB). The electron beam column 15 faces the stage 31 in, for example, the 1 st tilt direction in which the emission end 15a of the electron beam is tilted by a predetermined angle with respect to the vertical direction of the composite beam device 10. The electron beam column 15 is fixed to the sample chamber 11 such that the optical axis of the electron beam is parallel to the 1 st tilt direction.

The electron beam column 15 includes an electron source that generates electrons and an electron optical system that focuses and deflects the electrons emitted from the electron source. The electron optical system includes, for example, an electromagnetic lens, a deflector, and the like. The electron source and the electron optical system are controlled by a control signal output from the control device 25 in accordance with the irradiation position and irradiation condition of the electron beam.

The focused ion beam column 17 irradiates a Focused Ion Beam (FIB) to be irradiated in a predetermined irradiation region inside the sample chamber 11. The focused ion beam column 17 is configured to face an emission end 17a of a focused ion beam with respect to the stage 31 in the vertical direction of the composite beam apparatus 10, for example. The focused ion beam column 17 is fixed to the sample chamber 11 such that the optical axis of the focused ion beam is parallel to the vertical direction.

The focused ion beam column 17 includes an ion source that generates ions, and an ion optical system that focuses and deflects ions extracted from the ion source. The ion optical system includes, for example, a1 st electrostatic lens such as a condenser lens, a2 nd electrostatic lens such as an electrostatic deflector and an objective lens, and the like. The ion source and the ion optical system are controlled by a control signal output from the control device 25 in accordance with the irradiation position, the irradiation condition, and the like of the focused ion beam. The ion source is, for example, a liquid metal ion source using liquid gallium or the like, a plasma type ion source, a gas electric field ionization type ion source, or the like.

The particle beam column 19 irradiates an irradiation target in a predetermined irradiation region inside the sample chamber 11 with a Particle Beam (PB) of an ion beam or a neutral particle beam. The particle beam column 19 faces the stage 31 in, for example, a2 nd inclination direction (an inclination direction different from the electron beam column 15) in which the emission end 19a of each beam is inclined by a predetermined angle with respect to the vertical direction of the composite beam device 10. The particle beam column 19 is fixed to the sample chamber 11 such that the optical axis of each beam is parallel to the 2 nd inclination direction.

The particle beam device 1 including the particle beam column 19 according to the embodiment will be described below.

The respective optical axes of the electron beam column 15, the focused ion beam column 17, and the particle beam column 19 intersect at a predetermined position P above the sample stage 13, for example.

The mutual arrangement of the electron beam column 15, the focused ion beam column 17, and the particle beam column 19 may be replaced as appropriate. For example, the electron beam column 15 or the particle beam column 19 may be arranged in the vertical direction, and the focused ion beam column 17 may be arranged in an inclined direction inclined with respect to the vertical direction.

The composite beam apparatus 10 can perform imaging of an irradiated portion, various processing (excavation, trimming, and the like) by sputtering, formation of a deposited film, and the like by irradiating a focused ion beam or particle beam onto the surface of an irradiation target while scanning the surface. The composite beam apparatus 10 can perform processing for forming a sample piece (for example, a sheet sample, a needle sample, or the like) for transmission observation by a transmission electron microscope, an analysis sample piece for analysis by an electron beam, or the like from the sample S. The composite beam apparatus 10 can perform processing for making the specimen transferred to the specimen holder a thin film having a desired thickness suitable for transmission observation by a transmission electron microscope. The composite beam apparatus 10 can observe the surface of an irradiation target such as a sample S, a sample piece, and a needle by irradiating a focused ion beam, a particle beam, or an electron beam while scanning the surface of the irradiation target.

The secondary charged particle detector 21 detects secondary charged particles (secondary electrons and secondary ions) generated from an irradiation target by irradiation of a focused ion beam, a particle beam, an electron beam, or the like. The secondary charged particle detector 21 is connected to the control device 25, and a detection signal output from the secondary charged particle detector 21 is transmitted to the control device 25.

The composite beam apparatus 10 may be provided with other detectors, and is not limited to the secondary charged particle detector 21. Other detectors are, for example, EDS (Energy Dispersive X-ray Spectrometer) detectors, reflected Electron detectors and EBSD (Electron Back-Scattering Diffraction) detectors, etc. The EDS detector detects X-rays generated from an irradiation object by irradiation of an electron beam. The reflected electron detector detects reflected electrons reflected from an irradiation object by irradiation of the electron beam. The EBSD detector detects an electron ray backscatter diffraction pattern generated from an irradiation object by irradiation of an electron beam. In the secondary charged particle detector 21, a secondary electron detector for detecting secondary electrons and a reflected electron detector may be housed in a housing of the electron beam column 15.

The gas supply unit 23 is fixed to the sample chamber 11. The gas supply unit 23 includes a gas ejection unit (nozzle) disposed to face the stage 31. The gas supply unit 23 supplies an etching gas, a deposition gas, and the like to an irradiation target. The etching gas selectively promotes etching of the irradiation target by the focused ion beam depending on the material of the irradiation target. The deposition gas forms a deposition film based on deposits such as metal and insulator on the surface of the irradiation target.

The gas supply unit 23 is controlled by a control signal output from the control device 25 in accordance with the operation mode of the composite beam device 10 and the like.

The control device 25 collectively controls the operation of the composite beam device 10 based on, for example, a signal output from the input device 27 or a signal generated by a preset automatic operation control process.

The control device 25 is a software function Unit that functions by executing a predetermined program by a processor such as a CPU (Central Processing Unit). The software function Unit is an ECU (Electronic Control Unit) having a processor such as a CPU, a ROM (Read Only Memory) for storing a program, a RAM (Random Access Memory) for temporarily storing data, and an Electronic circuit such as a timer. At least a part of the control device 25 may be an integrated circuit such as an LSI (Large Scale Integration).

The input device 27 is, for example, a mouse, a keyboard, or the like that outputs a signal corresponding to an input operation by an operator.

The display device 29 displays various information of the composite beam device 10, image data generated from a signal output from the secondary charged particle detector 21, a screen for performing operations such as enlargement, reduction, movement, and rotation of the image data, and the like.

(particle beam device)

Fig. 2 is a diagram showing a configuration of the particle beam apparatus 1 including the particle beam column 19 according to the embodiment.

The particle beam apparatus 1 is, for example, a gas ion beam apparatus. The particle beam column 19 is fixed to the sample chamber 11. The particle beam column 19 includes an ion source 41 and an ion optical system 42. The ion source 41 and the ion optical system 42 are controlled by a control signal output from the control device 25 in accordance with the irradiation position, the irradiation condition, and the like of the particle beam.

The ion source 41 generates ions. The ion source 41 is, for example, a PIG (pencil Ionization Gauge) type ion source or the like, and generates ions of a rare gas such as argon (Ar) or other gas such as oxygen.

The ion source 41 can operate, for example, at an acceleration voltage in the range of 200V to 5 kV. When the acceleration voltage is 1kV, a particle flux corresponding to 20nA as an ion beam and a particle flux corresponding to 5nA as a neutral particle beam can be generated in the sample S. The image resolution of the secondary electron image based on an ion beam with an acceleration voltage of 1kV is about 50 microns.

The ion optical system 42 focuses, deflects, and neutralizes ions extracted from the ion source 41. The ion optical system 42 includes, for example, an extraction electrode 51, a condenser 52, a blanker 53, a blanking diaphragm 54, a charge exchange grid 55, an objective lens 56, and a deflector 57, which are arranged in this order from the ion source 41 side toward the emission end portion 19a side of the particle beam column 19 (i.e., the sample S side).

The extraction electrode 51 extracts ions from the ion source 41 by an electric field generated between the ion source 41 and the extraction electrode. The voltage applied to the extraction electrode 51 is controlled, for example, in accordance with the acceleration voltage of the ion beam.

The condenser lens 52 is, for example, an electrostatic lens including three electrodes arranged along the optical axis. The condenser lens 52 focuses the ion beam extracted from the ion source 41 through the extraction electrode 51. The condenser lens 52 changes the lens strength according to the degree of focusing of the ion beam in accordance with the mode in which the particle beam column 19 irradiates the ion beam as the particle beam to the sample S and the mode in which the neutral particle beam irradiates the sample S as the particle beam. For example, in a mode in which the particle beam column 19 irradiates the sample S with the neutral particle beam as a particle beam, the condenser lens 52 adjusts the applied voltage so that the ion beam is expanded further in a charge exchange grid 55 described later than in a mode in which the ion beam is irradiated to the sample S.

The blanker 53 includes, for example, a pair of electrodes (blanking electrodes) disposed to face each other with the optical axis sandwiched between both sides in a direction intersecting the traveling direction of the ion beam. The blanker 53 switches the shielding of the ion beam. For example, the blanker 53 performs shielding by deflecting the ion beam to collide with the blanking diaphragm 54, and releases shielding by not deflecting the ion beam.

Fig. 3 is a diagram schematically showing the configuration of the charge exchange gate 55 of the particle beam apparatus 1 according to the embodiment.

The charge exchange gate 55 is formed of a metal or the like having a predetermined shape such that at least a part of the ion beam collides with the metal or the like at one time without shielding the ion beam. The outer shape of the charge exchange grid 55 is, for example, a cylindrical shape having a central axis coaxial with the optical axis of the ion beam. The charge exchange gate 55 has a concave curved inner peripheral surface 55c whose inner diameter gradually decreases from the axial both end portions 55a toward the axial center portion 55 b.

The charge exchange gate 55 causes a part of the ions incident on the inner peripheral surface 55c at a shallow angle to absorb electrons, thereby exchanging charges and changing the ions into neutral particles. In the example shown in fig. 3, of the ion beams IB incident on the inside of the charge exchange grid 55, the neutral particle beam NB neutralized by charge exchange is emitted from the inside of the charge exchange grid 55 toward the objective lens 56 together with the ion beam IB not subjected to charge exchange.

As shown in fig. 2, the objective lens 56 is, for example, an electrostatic lens including three electrodes arranged along the optical axis. The objective lens 56 includes, for example, a deceleration electrode as a center electrode to which a voltage for forming an electric field for decelerating the ion beam is applied.

In the case of the mode in which the particle beam column 19 irradiates the ion beam as a particle beam to the sample S, the objective lens 56 focuses the ion beam to the sample S. In the mode in which the particle beam column 19 irradiates the neutral particle beam as a particle beam onto the sample S, the objective lens 56 applies a voltage equal to or higher than the kinetic energy of the ions to the deceleration electrode, thereby suppressing the passage of the ion beam. That is, the objective lens 56 is energized to decelerate and shield the ion beam.

The deflector 57 includes, for example, 2 or more electrodes arranged in a cylindrical shape so as to surround the optical axis of the ion beam. The deflector 57 scans the irradiation position of the ion beam with respect to the sample S. The deflector 57 performs raster scanning of a rectangular region on the surface of the sample S by applying a deflection voltage for two-dimensional scanning, for example.

(processing technology)

Fig. 4 is a diagram schematically illustrating an example of a processing process by the composite beam apparatus 10 according to the embodiment.

For example, in processing a sample S of an insulating material, first, an ion beam is irradiated from the particle beam column 19 to the sample S, and a processing point a2 as an object in a scanning range a1 is searched for from a scanning electron image of secondary electrons detected by the secondary charged particle detector 21. Next, the sample S is irradiated with the neutral particle beam from the particle beam column 19, and the machining point a2 is machined.

For example, when machining point a2 with an ion beam, there is a possibility that machining point A3 or the like having a shape other than a desired shape may be obtained by deforming the ion beam due to charging caused by long-time machining, the action of an electromagnetic field, or the like. In contrast, the machining using the neutral particle beam can perform the machining with high accuracy at the target machining point a 2.

Fig. 5 is a diagram schematically showing another example of a machining process by the particle beam apparatus according to the embodiment.

For example, in processing a sample S using both the electron beam column 15 and the particle beam column 19, first, the sample S is irradiated with an electron beam from the electron beam column 15, and a processing point a2 as an object in a scanning range a1 is searched for from a scanning electron image of secondary electrons detected by the secondary charged particle detector 21. Next, the sample S is irradiated with the neutral particle beam from the particle beam column 19, and the machining point a2 is machined. It should be noted that observation of the machining point a2 by the scanning electron image and machining of the machining point a2 by the neutral particle beam can be performed simultaneously. According to the processing of the neutral particle beam, the processing can be performed with high accuracy without being affected by the electromagnetic field generated in the electron beam column 15.

As described above, the composite beam apparatus 10 of the embodiment includes the objective lens 56 that reduces the ion beam on the downstream side of the charge exchange grid 55, and thereby can suppress irradiation of the sample S with the ion beam that is not neutralized when the sample S is irradiated with the neutral particle beam. Thereby, the ion beam and the neutral particle beam can be selectively and appropriately switched.

When the ion beam and the neutral particle beam are switched as the particle beam to be irradiated to the sample S, the condensing lens 52 for switching the focus of the ion beam by the change in the lens strength according to the degree of the focus of the ion beam is provided, whereby the neutralization efficiency of the ion beam in the charge exchange grid 55 can be appropriately switched.

By providing the blanker 53 and the blanking diaphragm 54 for shielding the ion beam on the upstream side of the charge exchange gate 55, when the sample S is irradiated with either the ion beam or the neutral particle beam as the particle beam, the irradiation can be easily stopped.

The particle beam column 19 can perform any one of position detection of a secondary electron scan image by the ion beam and processing by the neutral particle beam by selectively using the ion beam and the neutral particle beam.

By neutralizing the charge exchange by the charge exchange gate 55 in the particle beam column 19, it is possible to use reactive ions such as oxygen, for example, and to form a smaller optical system as compared with the gas charge exchange, for example.

(modification example)

A modified example of the embodiment will be described below. The same portions as those in the above embodiments are denoted by the same reference numerals, and the description thereof is omitted or simplified.

In the above embodiment, the outer shape of the charge exchange gate 55 is a cylindrical shape having the concave inner peripheral surface 55c, but the present invention is not limited thereto, and other shapes are possible. The surface of the charge exchange gate 55, which is charged by the collision with the ions, may have a shape necessary for obtaining a desired neutral particle beam shape, neutral particle density, or the like.

Fig. 6 is a diagram schematically showing the configuration of the charge exchange gate 55A in modification 1 of the embodiment.

The outer shape of the charge exchange gate 55A in modification 1 is, for example, a multiple cylindrical shape based on 2 or more cylindrical bodies 61 of different sizes having a central axis coaxial with the optical axis of the ion beam. The 2 or more cylindrical bodies 61 are, for example, a1 st cylindrical body 61(1), a2 nd cylindrical body 61(2), a3 rd cylindrical body 61(3), and a 4 th cylindrical body 61 (4).

The charge exchange gate 55A in modification 1 causes part of the ions incident on the inner circumferential surface of each tubular body 61 at a shallow angle to absorb electrons, thereby performing charge exchange and changing the ions into neutral particles. In the example shown in fig. 6, of the ion beams IB incident on the inside of the charge-exchange grid 55A, the neutral particle beam NB neutralized by the charge exchange on the inner peripheral surface of each cylindrical body 61 is emitted from the inside of the charge-exchange grid 55A toward the objective lens 56 together with the ion beam IB not subjected to the charge exchange.

According to modification 1, the neutralization efficiency can be improved by increasing the number of the tubular bodies 61 that collide with the ion beam.

Fig. 7 is a diagram schematically showing the configuration of the charge exchange gate 55B in modification 2 of the embodiment.

The charge exchange gate 55B in modification 2 is, for example, a tube having a central axis coaxial with the optical axis of the ion beam. The charge exchange gate 55B has a tapered concave inner peripheral surface 62c whose inner diameter gradually decreases from the entrance-side end 62a toward the exit-side end 62B in the axial direction of the center shaft.

The charge exchange gate 55B in modification 2 absorbs electrons in a part of ions incident on the inner circumferential surface 62c at a shallow angle, thereby exchanging charges and changing the ions into neutral particles. In the example shown in fig. 7, of the ion beams IB incident on the inside of the charge exchange grid 55B, the neutral particle beam NB neutralized by the multiple charge exchanges at the inner peripheral surface 62c is emitted from the inside of the charge exchange grid 55B toward the objective lens 56 together with the ion beam IB not subjected to the charge exchanges.

According to the modification 2, the neutralization efficiency can be improved by increasing the number of collisions with the ion beam in accordance with the shape of the charge exchange gate 55B.

In the above embodiment, the particle beam column 19 may include an acceleration electrode or the like for accelerating the ion beam.

Fig. 8 is a diagram schematically showing the configuration of the particle beam apparatus 1A according to modification 3 of the embodiment.

The particle beam barrel 19A of the particle beam apparatus 1A according to modification 3 includes an ion source 41 and an ion optical system 42A. The ion optical system 42A further includes an accelerating electrode 63 in addition to the ion optical system 42 of the above embodiment, for example.

The acceleration electrode 63 is disposed between the condenser lens 52 and the objective lens 56, for example, and is disposed so as to surround the blanker 53, the blanking diaphragm 54, and the charge exchange grid 55. The acceleration electrode 63 increases the motion energy of the ion beam, thereby reducing the respective aberrations of the ion beam and the neutral particle beam.

According to the modification 3, by providing the accelerating electrode 63 for accelerating the ion beam, it is possible to reduce the aberration between the ion beam and the neutral particle beam, and to improve the accuracy of processing and observation of the sample S.

In the above embodiment, the particle beam column 19 may include an electron confinement electrode, an electron generation device, and the like for increasing the neutralization efficiency of the charge exchange gate 55.

Fig. 9 is a diagram schematically showing the configuration of a particle beam apparatus 1B according to a 4 th modification of the embodiment. Fig. 10 is a diagram schematically showing the structure of the electron confining electrode 64 in the 4 th modification of the embodiment.

As shown in fig. 9, the particle beam column 19B of the particle beam device 1B according to modification 4 includes an ion source 41 and an ion optical system 42B. The ion optical system 42B includes, for example, the ion optical system 42 of the above embodiment, an electron confining electrode 64 and an electron generating device 65.

As shown in fig. 10, the electron confining electrode 64 is configured not to shield the ion beam but to cover the charge exchange gate 55. The electron confining electrode 64 generates an electric field that confines the secondary electrons generated in the charge exchange gate 55 and the primary electrons generated in the electron generating device 65 to the inside of the charge exchange gate 55 by applying a voltage. In the example shown in fig. 10, the orbitals EO of the secondary electrons generated in the charge exchange gate 55 stay inside the charge exchange gate 55.

The electron confining electrode 64 promotes neutralization of the ion beam-based charge exchange by confining each electron inside the charge exchange gate 55.

As shown in fig. 9, the electron generating device 65 supplies primary electrons to the inside of the charge exchange gate 55. The electron generating device 65 is, for example, a thermionic source or the like including a filament or the like that releases thermal electrons by heating. The electron generator 65 is disposed between the charge exchange grid 55 and the objective lens 56, for example.

According to the 4 th modification, the efficiency of neutralization of the charge exchange gate 55 can be improved by providing the electron confining electrode 64 and the electron generating device 65.

In the above-described modification 4, the electron generating device 65 is disposed outside the electron confining electrode 64, but the present invention is not limited thereto, and the electron generating device 65 may be disposed inside the electron confining electrode 64.

Fig. 11 is a diagram schematically showing the structure of the electron confining electrode 64 in the 5 th modification of the embodiment.

The electron generating device 65 in the modification 5 is disposed inside the electron confining electrode 64. In the example shown in fig. 11, orbitals EO of secondary electrons generated in the charge exchange gate 55 and primary electrons generated in the electron generating device 65 stay inside the charge exchange gate 55 by an equipotential line EL formed between the electron confining electrode 64 and the charge exchange gate 55.

According to the modification 5, the efficiency of neutralization of the charge exchange gate 55 can be improved by providing the electron generating device 65 disposed inside the electron confining electrode 64.

In the above-described 4 th and 5 th modifications, the electron-confining electrode 64 and the electron generator 65 are provided, but the present invention is not limited thereto, and only either may be provided. In addition, in the case where the electron confining electrode 64 is omitted, an electric field that confines the secondary electrons generated in the charge exchange gate 55 and the primary electrons generated in the electron generating device 65 inside the charge exchange gate 55 can be formed by directly applying a voltage to the charge exchange gate 55.

In the above embodiment, the central axis of the charge exchange grid 55 is coaxial with the optical axis of the ion beam, but the present invention is not limited thereto, and the central axis of the charge exchange grid 55 may be arranged to be offset from the optical axis of the ion beam.

Fig. 12 is a diagram schematically showing the configuration of a particle beam apparatus 1C according to modification 6 of the embodiment. Fig. 13 is a diagram schematically showing the configuration of the charge exchange gate 55C of the particle beam apparatus 1C according to modification 6 of the embodiment.

As shown in fig. 12, the particle beam column 19C of the particle beam device 1C according to modification 6 includes an ion source 41 and an ion optical system 42C. The ion optical system 42C includes, for example, a charge exchange gate 55C instead of the charge exchange gate 55 in the ion optical system 42 of the above embodiment, and further includes an upper deflector 66.

The charge exchange gate 55C of the 6 th modification is disposed so as to be shifted from the optical axis of the ion beam so as not to be incident thereon in the case of the mode in which the particle beam column 19C irradiates the sample S with the ion beam as the particle beam.

As shown in fig. 13, the outer shape of the charge exchange gate 55C in the 6 th modification is, for example, an aggregate of 2 or more flat plates 67 parallel to the optical axis of the ion beam. The 2 or more flat plates 67 are, for example, a1 st flat plate 67(1), a2 nd flat plate 67(2), a3 rd flat plate 67(3), and a 4 th flat plate 67(4) which are arranged in parallel in this order at a predetermined interval in the thickness direction.

The charge exchange gate 55C in modification 6 causes a part of ions incident on the surface of each flat plate 67 at a shallow angle to absorb electrons, thereby exchanging charges and changing the ions into neutral particles. In the example shown in fig. 13, of the ion beams IB incident on the charge exchange grid 55C, the neutral particle beam NB neutralized by charge exchange on the surface of each plate 67 is reflected from the charge exchange grid 55C toward the objective lens 56.

As shown in fig. 12, the upper deflector 66 includes, for example, 2 or more electrodes arranged in a cylindrical shape so as to surround the optical axis of the ion beam. The upper deflector 66 is disposed upstream of the charge exchange grid 55C, for example, between the blanking aperture 54 and the charge exchange grid 55C. When the particle beam column 19C irradiates the sample S with the ion beam as a mode of the particle beam, the upper deflector 66 guides the ion beam to the outside of the charge exchange grid 55C without deflecting the ion beam by, for example, not applying a deflection voltage. When the particle beam column 19C irradiates the sample S with a neutral particle beam as a mode of a particle beam, a deflection voltage is applied to the upper deflector 66, for example, to deflect the ion beam and guide the ion beam toward the charge exchange grid 55C.

The upper deflector 66 can change, for example, a desired neutralization efficiency of the charge exchange grid 55C, a desired irradiation position of the neutral particle beam on the sample S, and the like by adjusting the amount of deflection of the ion beam in accordance with the applied deflection voltage.

In modification 6, the ion beam and the neutral particle beam may not be switched by the condenser lens 52 when the ion beam and the neutral particle beam are switched as the particle beam.

According to the 6 th modification, by providing the upper deflector 66 for switching the deflection of the ion beam when switching the ion beam and the neutral particle beam as the particle beam irradiated to the sample S, the neutralization efficiency of the ion beam in the charge exchange grid 55 can be appropriately switched.

In the above embodiment, the ion beam is made incident on the charge exchange gate 55 even when the particle beam column 19 irradiates the sample S with the ion beam as the mode of the particle beam, but the present invention is not limited to this, and the ion beam may be guided to the outside of the charge exchange gate 55.

Fig. 14 is a diagram schematically showing the configuration of a particle beam apparatus 1D according to modification 7 of the embodiment.

The particle beam barrel 19D of the particle beam device 1D according to modification 7 includes an ion source 41 and an ion optical system 42D. The ion optical system 42D includes, for example, the ion optical system 42 of the above embodiment, and further includes an upper deflector 66 and an intermediate deflector 68.

The upper deflector 66 and the intermediate deflector 68 each include, for example, 2 or more electrodes and the like arranged in a cylindrical shape so as to surround the optical axis of the ion beam. The upper deflector 66 and the middle deflector 68 are disposed, for example, between the blanking diaphragm 54 and the charge exchange gate 55C. The upper deflector 66 and the intermediate deflector 68 are arranged in this order from the ion source 41 side toward the emission end 19a side of the particle beam column 19D (i.e., the sample S side).

When the particle beam column 19D irradiates the sample S with an ion beam as a mode of the particle beam, for example, by applying a deflection voltage, the upper deflector 66 and the intermediate deflector 68 deflect the ion beam and guide the ion beam to the outside of the charge exchange grid 55. When the particle beam column 19C irradiates the sample S with the neutral particle beam as a mode of the particle beam, the upper deflector 66 and the intermediate deflector 68 guide the ion beam toward the charge exchange grid 55 without deflecting the ion beam by, for example, not applying the deflection voltage.

According to the 7 th modification, by providing the upper deflector 66 and the middle deflector 68 that switch the deflection of the ion beam when switching the ion beam and the neutral particle beam as the particle beam irradiated to the sample S, the neutralization efficiency of the ion beam in the charge exchange grid 55 can be appropriately switched.

The particle beam column 19 may include a mechanism for adjusting the position of the particle beam so that the irradiation point of the composite beam apparatus 10 on the sample S is the same. For example, the particle beam column 19 may include a deflector arranged upstream of the charge exchange grid 55 to finely adjust the incident angle of the ion beam, or may include a mechanism for mechanically moving the entire particle beam column 19. For example, the deflector disposed on the upstream side of the charge exchange gate 55 is a deflector for adjusting the horizontal direction and the vertical direction on the sample S, and may be used in common with the upper deflector 66 in the above-described 6 th modification and 7 th modification, or may be disposed separately from the upper deflector 66.

In the above embodiment, the composite beam device 10 includes the electron beam column 15, the focused ion beam column 17, and the particle beam column 19, but is not limited thereto. For example, the composite beam device 10 may be a composite beam device based on a combination of the electron beam column 15 and the particle beam column 19.

The embodiments of the present invention are presented as examples and are not intended to limit the scope of the invention. These embodiments may be implemented in other various manners, and various omissions, substitutions, and changes may be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.

Description of the symbols

1, 1A, 1B, 1C, 1D … particle beam apparatus, 10 … composite beam apparatus, 11 … sample chamber, 12 … sample holder, 13 … sample stage, 15 … electron beam column, 17 … focused ion beam column, 19A, 19B, 19C, 19D … particle beam column, 21 … secondary charged particle detector (detector), 23 … gas supply, 25 … control, 27 … input device, 29 … display device, 41 … ion source (charged particle source), 42A, 42B, 42C, 42D … ion optical system, 51 … extraction electrode, 52 … condenser (switch, electrostatic lens), 53 … blanker (shield), 54 … blanking (shield), 55A, 55B, 55C … charge exchange grid (switch), 56 … objective (reduction 63), 57 acceleration deflector, … acceleration electrode, 64 … electron confinement electrodes, 65 … electron generation devices, 66 … upper deflectors (switching unit, deflector, upstream deflector), 68 … middle deflectors (switching unit, deflector), S … sample, PB … particle beam, IB … ion beam, NB … neutral particle beam.