JP2009037910A - Composite charged particle beam apparatus and processing observation method - Google Patents

Abstract

A composite charged particle beam apparatus capable of observing a sample while processing it without contamination is provided.
The composite charged particle beam apparatus of the present invention includes an ion beam irradiation system 20 having a gas field ion source, and an irradiation axis thereof is 90 degrees or narrower than 90 degrees with respect to the irradiation axis of the ion beam irradiation system 20. An electron beam irradiation system 50 arranged at an angle, and a sample stage that supports the sample at the intersection of the ion beam 20A emitted from the ion beam irradiation system 20 and the electron beam 50A emitted from the electron beam irradiation system 50 14 and a gas gun 11 for supplying a functional gas for deposition or etching to a beam irradiation position on the sample.
[Selection] Figure 1

Description

  The present invention relates to a composite charged particle beam apparatus and a processing observation method.

2. Description of the Related Art Conventionally, as a processing observation apparatus used for evaluation of a semiconductor process, an apparatus including a processing ion beam irradiation system and an observation electron beam irradiation system is known (see Patent Documents 1 to 4). In addition, a method of forming a fine three-dimensional structure by deposition using a focused ion beam and a gas gun is known (see Patent Document 5).
Japanese Patent Laid-Open No. 2-123749 JP-A-6-231720 JP-A-7-169429 JP 2005-310757 A International Publication No. 02/044079 Pamphlet

  In the techniques described in the patent documents listed above, since a gallium ion beam is used for processing a sample, ion implantation into the sample by processing is inevitable. In particular, when processing and observation of a sample (wafer) extracted from the semiconductor manufacturing process is performed, contamination with gallium ions makes it impossible to return to the process.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a composite charged particle beam apparatus that can be observed while processing a sample without contaminating it. In particular, it is intended to realize ultrafine processing and observation with an ultrafine beam obtained from a gas field ion source.

In order to solve the above problems, a composite charged particle beam apparatus according to the present invention includes an ion beam irradiation system including a gas field ion source and an irradiation axis of 90 degrees or 90 degrees with respect to the irradiation axis of the ion beam irradiation system. An electron beam irradiation system disposed at a narrower angle, a sample stage that supports the sample at the intersection of the ion beam emitted from the ion beam irradiation system and the electron beam emitted from the electron beam irradiation system, And a gas gun for supplying a functional gas for deposition or etching to a beam irradiation position on the sample.
According to this configuration, since the ion beam irradiation system and the gas gun are provided, it is possible to quickly and easily perform formation of a structure by gas assist deposition, processing of a sample by gas assist etching, and the like. In particular, an ion beam irradiation system equipped with a gas field ion source can perform processing with high precision because the beam diameter can be reduced to 1 nm or less.
Furthermore, since the electron beam irradiation system is provided, it is possible to perform sample observation using the electron beam irradiation system while performing sample processing using the ion beam irradiation system. Therefore, for example, in the case of processing applications, it is possible to perform processing with an ion beam while confirming the finishing degree of processing.
Further, since the ion beam irradiation system uses a gas ion source, the sample is not contaminated by the ion beam irradiation. Therefore, even after processing and observing the sample extracted from the manufacturing process of the semiconductor device with the composite charged particle beam apparatus of the present invention, the sample can be returned to the process, and the product is not wasted.

It is preferable that the ion beam irradiation system is disposed above the sample stage in the vertical direction, while the electron beam irradiation system is disposed so as to be inclined with respect to the vertical direction.
By arranging the ion beam irradiation system vertically above the sample stage in this way, it becomes easier to perform processing observation using an ion beam irradiation system that requires a highly precise position control with a small beam diameter.

It is preferable that the gas field ion source includes an emitter, an extraction electrode having an opening facing the tip of the emitter, and a gas supply unit that supplies a gas to be the ions.
With such a gas field ion source, an ion beam having a small beam diameter can be stably formed.

The ions are preferably helium ions.
With this configuration, a composite charged particle beam apparatus including an ion beam irradiation system that can obtain a sample image with almost no sputtering of the sample is obtained.

A detection device for detecting at least one of secondary charged particles generated from the sample by irradiation of the ion beam or the electron beam and charged particles transmitted through the sample, and displaying an image of the sample based on the output of the detection device It is preferable to include an image display device.
With this configuration, the sample image can be observed by ion beam irradiation or electron beam.

  It is preferable that the detection device includes at least one of an electron detector, an ion detector, and a transmitted charged particle detector. That is, it is preferable to provide a device that can detect any of secondary electrons, secondary ions, and transmitted charged particles generated from a sample by ion beam irradiation or electron beam irradiation.

The processing observation method of the present invention includes a step of processing the sample by irradiating the sample with an ion beam from an ion beam irradiation system including a gas field ion source and supplying a gas to the ion beam irradiation position of the sample. And observing the sample by irradiating the sample with an electron beam.
According to this processing observation method, the sample can be processed quickly and efficiently by gas assist deposition or gas assist etching by ion beam irradiation while supplying gas. Moreover, it can observe, avoiding damage of a sample by electron beam irradiation. In addition, since metal ions are not irradiated, it is possible to perform the process while avoiding contamination of the sample.
In particular, in the present invention, since an ion beam irradiation system having a beam diameter that can be reduced is used, fine and high-precision processing can be easily performed, and higher-level processing observation can be performed. it can.
In addition, although gas assist processing by ion beam irradiation has been described above, gas assist processing by electron beam irradiation can also be performed.
Furthermore, it is also possible to irradiate a reversely charged electron or ion beam to prevent charging during observation of the insulator processing.

It is preferable to irradiate the sample with the electron beam from a direction intersecting the ion beam at an acute angle or approximately 90 degrees.
According to this processing observation method, after processing with an ion beam, it is possible to perform observation using an electron beam continuously without almost adjusting the position of the sample, and quick observation is possible.

According to the composite charged particle beam apparatus of the present invention, formation of a structure by gas-assisted deposition, processing of a sample by gas-assisted etching, and the like can be performed quickly and easily. In particular, an ion beam irradiation system equipped with a gas field ion source can perform processing with high precision because the beam diameter can be reduced to 1 nm or less.
Further, according to the processing observation method of the present invention, the sample can be processed quickly and efficiently by gas assist deposition or gas assist etching by ion beam irradiation while supplying gas. Moreover, it can observe, avoiding damage of a sample by electron beam irradiation. In addition, since metal ions are not irradiated, it is possible to perform the process while avoiding contamination of the sample.

Hereinafter, embodiments of the composite charged particle beam apparatus of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic perspective view of the composite charged particle beam apparatus of the present embodiment. FIG. 2 is a schematic sectional view of the composite charged particle beam apparatus 100.

  As shown in FIGS. 1 and 2, the composite charged particle beam apparatus 100 of the present embodiment includes a vacuum chamber 13, an ion beam irradiation system 20, an electron beam irradiation system 50, a sample stage 16, a manipulator 17, A secondary charged particle detector 18, a transmitted charged particle detector 19, and a gas gun 11 are provided. The inside of the vacuum chamber 13 can be depressurized to a predetermined degree of vacuum, and a part or all of the above-described components are arranged in the vacuum chamber 13.

  In this embodiment, an ion beam (focused ions) is applied to a sample (processing object or observation object) on a sample stage 16 disposed in a vacuum chamber 13 from an ion beam irradiation system 20 having a focused ion beam column. Beam) 20A is irradiated. The electron beam irradiation system 50 irradiates the sample at the same position as the ion beam 20A with the electron beam 50A emitted from the electron beam column.

As shown in FIG. 2, the electron beam irradiation system 50 includes an electron source 54 that emits electrons and an electron optical system 55 that shapes and scans the electrons emitted from the electron source 54 into a beam. A known configuration can be adopted as the electron beam irradiation system 50.
Secondary electrons generated by irradiating the sample Wa with the electron beam emitted from the electron beam irradiation system 50 are detected by the secondary charged particle detector 18 to obtain an SEM (scanning electron microscope) image of the sample Wa. To do. In addition, a TEM (transmission electron microscope) image or a STEM (scanning transmission electron microscope) image can be obtained by detecting the electrons that have passed through the sample with the transmission charged particle detector 19.

  The ion beam irradiation system 20 forms a focused ion beam (ion beam 20A) by irradiating the sample Wa or the sample Wb with a gas field ion source 21 that generates and flows out ions, and ions that flow out from the gas field ion source 21. The ion optical system 25 is provided.

  The ion optical system 25 includes, for example, a condenser lens that focuses the ion beam, an aperture that narrows the ion beam, an aligner that adjusts the optical axis of the ion beam, an objective lens that focuses the ion beam on the sample, And a deflector for scanning the ion beam.

Here, FIG. 3 is a schematic sectional view showing the gas field ion source 21.
As shown in FIG. 3, the gas field ion source 21 includes an ion generation chamber 21 a, an emitter 22, an extraction electrode 23, and a cooling device 24. A cooling device 24 is disposed on the wall of the ion generation chamber 21a, and a needle-like emitter 22 is mounted on the surface of the cooling device 24 facing the ion generation chamber 21a. The cooling device 24 cools the emitter 22 with a refrigerant such as liquid nitrogen accommodated therein. In the vicinity of the opening end of the ion generation chamber 21a, an extraction electrode 23 having an opening 23a is disposed at a position facing the tip 22a of the emitter 22.

The inside of the ion generation chamber 21a is maintained in a desired high vacuum state using an exhaust device (not shown). A gas supply source 26 is connected to the ion generation chamber 21a via a gas introduction pipe 26a, and a small amount of gas (for example, helium gas) is supplied into the ion generation chamber 21a.
Note that the gas supplied from the gas supply source 26 in the gas field ion source 21 is not limited to helium, and may be a gas such as neon, argon, or xenon. Further, a plurality of types of gases may be supplied from the gas supply source 26 so that the gas types can be switched according to the use of the ion beam irradiation system 20.

  The emitter 22 is a member formed by coating a noble metal such as platinum, palladium, iridium, rhodium, and gold on a needle-like base material made of tungsten or molybdenum, and its tip 22a is a pyramid sharpened at the atomic level. It is in the shape. The emitter 22 is kept at a low temperature of about 78K or less by the cooling device 24 when the ion source is operated. A voltage is applied between the emitter 22 and the extraction electrode 23 by a power source 27.

  When a voltage is applied between the emitter 22 and the extraction electrode 23, a very large electric field is formed at the sharply pointed tip 22a, and helium atoms 26m that are polarized and attracted to the emitter 22 pass through the tip 22a. Among them, electrons are lost by tunneling at a position where the electric field is high to become helium ions (field ionization). The helium ions repel the emitter 22 held at a positive potential and jump out to the extraction electrode 23 side, and the helium ions emitted from the opening 23a of the extraction electrode 23 to the ion optical system 25 constitute an ion beam. .

  The tip 22a of the emitter 22 has a very sharp shape, and helium ions jump out of the tip 22a. Therefore, the energy distribution width of the ion beam emitted from the gas field ion source 21 is extremely narrow, and the plasma type gas ion source 34 and liquid Compared with a metal ion source, an ion beam having a small beam diameter and high brightness can be obtained.

If the voltage applied to the emitter 22 is too large, the constituent elements (tungsten and platinum) of the emitter 22 are scattered along with the helium ions to the extraction electrode 23 side, so that it is applied to the emitter 22 during operation (during ion beam emission). The voltage is maintained at such a level that the constituent elements of the emitter 22 itself do not jump out.
On the other hand, the shape of the tip 22a can be adjusted using the fact that the constituent elements of the emitter 22 can be manipulated in this way. For example, the ion beam diameter can be increased by intentionally removing the element located at the forefront of the tip 22a to widen the region for ionizing the gas.
Further, since the emitter 22 can be rearranged by heating without causing the noble metal element on the surface to jump out, the sharpened shape of the tip 22a dulled by use can be recovered.

  1 and 2, the sample stage 16 supports the sample stage 14 and the sample holder 15 so as to be movable. A sample Wa (for example, a semiconductor wafer) is placed on the sample stage 14, and a minute sample Wb produced from the sample Wa is placed on the sample holder 15. And the sample stage 16 can displace the sample stand 14 and the sample holder 15 by 5 axes. That is, an XYZ moving mechanism 16b that moves the sample stage 14 along an X axis and a Y axis that are parallel to the horizontal plane and orthogonal to each other, and a Z axis that is orthogonal to the X axis and the Y axis, and the sample stage 14 And a rotation mechanism 16c that rotates the sample table 14 around the Z axis, and a tilt mechanism 16a that rotates the sample stage 14 around the X axis (or Y axis). The sample stage 16 is configured to move a specific position of the sample Wa (sample Wb) to a position where the ion beam is irradiated by displacing the sample stage 14 about five axes.

The inside of the vacuum chamber 13 can be depressurized to a predetermined degree of vacuum. In the vacuum chamber 13, a manipulator 17, a secondary charged particle detector 18, a transmitted charged particle detector 19, a gas gun 11, Is provided.
The manipulator 17 supports the sample Wb produced from the sample Wa, and moves the manipulator 17 and the sample holder 15 relative to each other while the sample Wb is instructed, so that the sample stage 14 moves to the sample holder 15. The sample Wb is transported. When transporting, the sample stage 16 may be driven with the manipulator 17 fixed to move the sample holder 15 to a position where the sample Wb is supported, or the sample Wb may be transported by moving the manipulator 17. Good.

  The secondary charged particle detector 18 is a secondary particle emitted from the sample Wa or the sample Wb when the sample Wa or the sample Wb is irradiated with the focused ion beam or the electron beam from the ion beam irradiation system 20 or the electron beam irradiation system 50. Detect electrons and secondary ions. The transmitted charged particle detector 19 also detects ions or electrons transmitted through the sample Wa or the sample Wb when the focused ion beam or the electron beam is irradiated from the ion beam irradiation system 20 or the electron beam irradiation system to the sample Wa or the sample Wb. To detect.

  The gas gun 11 emits a predetermined gas such as an etching gas or a deposition gas to the samples Wa and Wb. By irradiating the samples Wa and Wb with the ion beam 20A while supplying the etching gas from the gas gun 11, the etching rate of the sample by the ion beam can be increased. On the other hand, if the samples Wa and Wb are irradiated with an ion beam while supplying the deposition gas from the gas gun 11, a deposit of metal or insulator can be formed on the samples Wa and Wb.

  Moreover, the composite charged particle beam apparatus 100 is provided with the control apparatus 30 which controls each part which comprises the said apparatus. The control device 30 is connected to the ion beam irradiation system 20, the electron beam irradiation system 50, the secondary charged particle detector 18, the transmitted charged particle detector 19, and the sample stage 16. Further, a display device 38 that displays the sample Wa and the sample Wb as an image based on the output from the secondary charged particle detector 18 or the transmitted charged particle detector 19 is provided.

  The control device 30 comprehensively controls the composite charged particle beam device 100 and converts secondary charged particles or transmitted charged particles detected by the secondary charged particle detector 18 or the transmitted charged particle detector 19 into a luminance signal. Then, image data is generated, and this image data is output to the display device 38. Thereby, the display device 38 can display the sample image as described above.

  Further, the control device 30 drives the sample stage 16 based on a software command or an operator input, and adjusts the position or posture of the sample Wa or the sample Wb. Thereby, the irradiation position and irradiation angle of the ion beam on the sample surface can be adjusted. For example, the sample stage 16 can be driven in conjunction with a switching operation between the ion beam irradiation system 20 and the electron beam irradiation system 50 to move or tilt the sample Wa or the sample Wb.

  In the composite charged particle beam apparatus 100 of the present embodiment having the above-described configuration, the ion beam irradiation system 20 including the field emission ion source 21 can have a source size of 1 nm or less and an ion beam energy spread of 1 eV or less. The beam diameter can be reduced to 1 nm or less. By providing the ion beam irradiation system 20 that can narrow the beam diameter in this way, it is possible to perform fine processing (etching, deposition) on the sample.

  If the ion beam 20A is composed of helium ions, the sample is hardly etched if the sample is simply irradiated with the ion beam. However, the sample is irradiated with the ion beam 20A while supplying an etching assist gas from the gas gun 11. Thus, the sample can be processed at a practical speed. Further, if the ion beam 20A is composed of neon ions or argon ions having a mass larger than that of helium ions, the processing efficiency can be improved.

  And in the composite charged particle beam apparatus 100 of this embodiment, since the electron beam irradiation system 50 is provided with the ion beam irradiation system 20, while processing the sample Wa or the sample Wb using the ion beam irradiation system 20, Observation of the sample Wa or the sample Wb using the electron beam irradiation system 50 is possible. That is, SEM and STEM observations using the electron beam irradiation system 50 are possible during processing using the ion beam irradiation system 20. Therefore, according to the composite charged particle beam apparatus 100 of the present embodiment, it is possible to perform processing by the ion beam irradiation system 20 while confirming the finish, and it is possible to finish in an accurate position and size.

Furthermore, in the composite charged particle beam apparatus 100 of the present embodiment, sample observation using the ion beam irradiation system 20 can also be performed. In the ion beam 20A, since the interaction volume in the sample extends in the depth direction from the surface and the spread in the surface direction on the sample surface becomes small, the sample image accurately reflects the information of the position irradiated with the ion beam. And charge up of the sample can be suppressed. Furthermore, since the momentum of helium ions is very large relative to the momentum of electrons, more secondary electrons are emitted from the sample surface.
Thus, a sample image with high resolution and high contrast can be obtained by irradiating the sample with the ion beam 20A and observing the secondary charged particle image.

  In addition, since the composite charged particle beam apparatus 100 includes the ion beam irradiation system 20 and the electron beam irradiation system 50, for example, in processing observation of an insulator, charging by one beam irradiation can be performed with a reverse charge by the other beam irradiation. Can be neutralized by feeding.

  Further, the composite charged particle beam apparatus 100 of the present embodiment does not use a liquid metal ion source for the ion beam irradiation system 20. Therefore, the sample subjected to the processing in the composite charged particle beam apparatus 100 is not contaminated with metal ions (gallium ions or the like). For example, after inspecting the sample extracted from the manufacturing process of the semiconductor device, the sample is again used. It becomes possible to return to the process. Thereby, the sample used in the sampling inspection is not wasted.

  In the present embodiment, as shown in FIG. 2, the ion beam irradiation system 20 is disposed vertically above the sample stage 16, and the sample Wa or the sample Wb is irradiated with the ion beam 20A in the vertical direction. On the other hand, the electron beam irradiation system 50 is arranged to be inclined with respect to the vertical direction, and irradiates the electron beam 50A in an oblique direction to the sample Wa or the sample Wb. As described above, if the ion beam 20A made of helium ions is emitted along the vertical direction, high-precision stage control is facilitated during processing by the ion beam 20A, and desired accuracy is easily obtained.

  In the present embodiment, the intersection angle between the ion beam 20A and the electron beam 50A is preferably 20 ° or more and 70 ° or less. By setting it as such a range, the electron beam 50A can be irradiated to the site | part processed with the ion beam 20A at a suitable angle. Therefore, the processing position of the sample Wa or the sample Wb can be accurately observed from an angle different from that of the ion beam 20A without moving the sample stage 14.

  The arrangement of the ion beam irradiation system 20 and the electron beam irradiation system 50 is not limited to that shown in FIG. 2, and various arrangement forms can be employed. For example, in FIG. 2, the ion beam irradiation system 20 is disposed obliquely with respect to the vertical direction of the sample Wa, and is disposed so as to irradiate the ion beam 20A obliquely with respect to the horizontally disposed sample Wa or Wb. Also good.

[Processing observation method and processing method]
Next, a processing observation method using the composite charged particle beam apparatus 100 of the previous embodiment will be described with reference to the drawings. The composite charged particle beam apparatus 100 can be suitably used for sample processing observation such as cross-section processing observation of a sample, preparation of a TEM (transmission electron microscope) sample, and observation.

<Section processing observation>
FIG. 4 is a diagram illustrating a method for observing a cross section of a sample by the composite charged particle beam apparatus 100. In FIG. 4, only a part of the sample is shown for easy viewing of the drawing.
In the processing observation method of this example, the ion beam irradiation system 20 is used for processing the sample Wa, and the electron beam irradiation system 50 is used for observation of the processed sample Wa.

First, as shown in FIG. 4A, the surface portion of the sample Wa is partially removed by irradiating the surface of the sample Wa while scanning the ion beam 20A, thereby forming a recess Wr having a rectangular cross section. At this time, the concave portion Wr can be rapidly formed by irradiating the ion beam 20A while supplying the assisting etching gas from the gas gun 11.
Then, as shown in FIG. 4B, the secondary electrons generated by the electron beam 50 </ b> A are irradiated with the secondary charged particle detector 18 by irradiating the surface Ws exposed as the inner wall of the formed recess Wr. The sample image can be displayed on the display device 38 based on the detection result.

According to the processing observation method of this example, since the electron beam irradiation system 50 is disposed obliquely with respect to the ion beam irradiation system 20, the surface Ws is not tilted again after processing by the ion beam 20A. Can be observed, and rapid processing observation is possible.
Further, since the sample Wa is not irradiated with metal ions, the sample Wa is not contaminated by the metal ion implantation, and the processing and observation can be performed without changing the state of the sample Wa.

  Furthermore, in the processing observation method of this example, cross-section processing observation in which the cross-section processing by the ion beam irradiation system 20 and the cross-section observation by the electron beam irradiation system 50 are continuously performed alternately is also possible. That is, after the cross section observation by the electron beam irradiation system 50 shown in FIG. 4B, the portion including the surface Ws is selectively removed by irradiating the ion beam 20A in the vicinity of the surface Ws. Observation is performed by irradiating the electron beam 50A to the newly exposed cross section by this processing. Then, as shown in FIG. 4C, the sample Wa can be three-dimensionally processed and observed by observing the cross sections that are sequentially exposed by the processing.

  In the processing observation method of this example, sample observation (SIM observation) using the ion beam irradiation system 20 is also possible. That is, secondary electrons and secondary ions generated by irradiating the sample with a helium ion beam emitted from the ion beam irradiation system 20 are detected by the secondary charged particle detector 18, whereby the electron beam irradiation system 50 is changed. It is possible to obtain a sample image having a contrast different from that used.

<Formation of fine structure>
FIG. 5 is a view showing a fine structure forming method (processing method) on a sample by the composite charged particle beam apparatus 100. In the processing method of this example, the ion beam irradiation system 20 and the gas gun 11 are used for forming a fine structure on the sample substrate Wc.

  First, as shown in FIG. 5A, the first structure 110 made of, for example, carbon or metal is irradiated by irradiating the ion beam 20A while blowing the deposition gas from the gas gun 11 onto the sample substrate Wc. Form. Next, as illustrated in FIG. 5B, the ion beam 20 </ b> A is irradiated onto the first structure 110 while the deposition gas is blown from the gas gun 11 onto the first structure 110, and the second structure 110 is exposed to the second structure 110. The structure 111 is formed.

  Thereafter, similarly, by forming a structure on the second structure 111, a fine structure having an arbitrary three-dimensional shape can be formed on the sample substrate Wc. For example, a minute coil 113 having a diameter of several nanometers to several hundreds of nanometers as shown in FIG. 5C, a micro drill 114 having a diameter of several nanometers to several hundreds of nanometers as shown in FIG. Can be formed.

According to the processing method using the composite charged particle beam apparatus 100 of the present embodiment, the fine structure can be formed by the deposition using the ion beam 20A capable of reducing the beam diameter to a small size, and the structure having a minute size can be formed. Objects can be formed easily and accurately.
Further, the formed structure can be observed by irradiating the electron beam irradiation system 50 with the electron beam 50A. With such a processing method, since fine processing can be performed while confirming the finish of the structure, a fine structure can be formed with high yield. This processing method can be suitably used, for example, for manufacturing (etching) an atom probe that requires a very sharp tip shape.
When forming an axially symmetric structure such as the coil 113 or the drill 114, it is preferable to use a sample stage 16 that rotates the sample stage 14 or the sample holder 15 in a horizontal plane. Thereby, a fine structure can be formed easily and with high accuracy.

(Second Embodiment)
FIG. 6 is a view showing a composite charged particle beam apparatus 200 in which the arrangement of the ion beam irradiation system 20 and the electron beam irradiation system 50 is changed. In the composite charged particle beam apparatus 200 shown in FIG. 6, the ion beam irradiation system 20 is disposed vertically above the sample Wa, and the electron beam irradiation system 50 is disposed on the side of the sample Wa. The ion beam 20A and the electron beam 50A are emitted so as to be substantially orthogonal to each other. The transmitted charged particle detector 19 is disposed on the extension of the electron beam 50A. In the present embodiment, it is preferable to use a sample stage 16 that can tilt at least one of the sample stage 14 and the sample holder 15 in the range of 0 ° to 90 °.

  As shown in FIG. 6, since the ion beam 20A and the electron beam 50A are arranged so as to be substantially orthogonal to each other, the electron beam 50A is incident perpendicularly to the processed surface of the sample processed by the ion beam irradiation system 20. Can be made. Therefore, according to the composite charged particle beam apparatus 200 shown in FIG. 6, fabrication of a TEM (transmission electron microscope) sample and nano-order size processing such as an atom probe can be completed by observation using the electron beam irradiation system 50. It can be carried out efficiently while checking.

  Further, the arrangement shown in FIG. 6 makes it difficult for the lens barrel of the ion beam irradiation system 20 and the lens barrel of the electron beam irradiation system 50 to interfere with each other, so that the electron beam irradiation system 50 approaches the sample Wa or the sample Wb. WD (Working Distance) can be reduced. As a result, the beam diameter of the electron beam 50A can be reduced, and high-resolution observation becomes possible.

  In the composite charged particle beam apparatus 200, the ion beam irradiation system 20 and the electron beam irradiation system 50 may be replaced with each other. In this case, the same function and effect can be obtained.

<TEM sample preparation and observation>
FIG. 7 is a diagram showing a method for processing a TEM sample by the composite charged particle beam apparatus 200.
In the processing method of this example, the sample Wa is processed using the ion beam irradiation system 20 to obtain the sample Wb which is a TEM sample, and this is observed using the electron beam irradiation system 50.

First, as shown in FIG. 7 (a), the surface of the sample Wa is partially removed by irradiating the ion beam 20A while scanning, and the bottom surface is sloped on both sides of the portion to be the sample Wb which is a TEM sample. The concave portions Wr and Wr are formed. Further, as shown in FIG. 7B, processing is performed with the ion beam 20A until the portion that becomes the observation region of the sample Wb becomes a thin film having a desired thickness.
At this time, it is preferable to perform gas assist etching or gas assist deposition using the gas gun 11 together. By using the gas gun 11 in combination, the etching and deposition processing speed can be improved, and the sample Wb can be produced efficiently.
Then, the sample Wb as a TEM sample is obtained by taking out the sample Wb from the sample Wa using the manipulator 17.

  Furthermore, in the composite charged particle beam apparatus 100 of the present invention, the produced sample Wb can be observed. That is, as shown in FIG. 7C, the sample Wb taken out is moved to the sample holder 15 by the manipulator 17. The sample Wb is irradiated with the electron beam 50A, and the transmitted electrons are detected by the transmitted charged particle detector 19. Further, when additional processing of the sample Wb is necessary, the additional processing can be performed on the sample holder 15 by the ion beam 20A. In this way, the sample image can be displayed on the display device 38 based on the detection result of the transmitted charged particle detector 19.

  According to this processing method, when the TEM sample is manufactured, the processing is performed using the ion beam irradiation system 20 capable of reducing the beam diameter, so that a sample Wb in which the thin film portion to be observed is finished with high accuracy can be obtained. it can. In addition, since the samples Wa and Wb are not irradiated with metal ions, it is possible to avoid adverse effects on the sample due to the implantation of metal ions.

  In particular, if the sample stage 16 includes a sample stage 14 or a sample holder 15 that can be freely tilted in the range of 0 ° to 90 ° with respect to the horizontal direction, the beam is incident upon processing and observation. A large degree of freedom is obtained at the corners. Therefore, observation in various forms can be easily performed. Further, when the microstructure is formed using the composite charged particle beam apparatus 200 of the present embodiment, the same action can be obtained and the microstructure can be easily formed.

1 is a schematic configuration diagram of a composite charged particle beam apparatus according to a first embodiment. 1 is a schematic cross-sectional view of a composite charged particle beam apparatus according to a first embodiment. Sectional drawing of a field emission type ion source. The figure which shows the cross-section processing observation method which is one form of a processing observation method. The figure which shows the fine structure formation method which is one form of a processing method. The schematic block diagram of the composite charged particle beam apparatus which concerns on 2nd Embodiment. The figure which shows the TEM sample preparation and observation method which are one form of a process observation method.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 Gas gun, 13 Vacuum chamber, 14 Sample stand, 15 Sample holder, 16 Sample stage, 17 Manipulator, 18 Secondary charged particle detector, 19 Transmission charged particle detector, 20 Ion beam irradiation system, 20A Ion beam, 21 Gas Field ion source, 21a ion generation chamber, 22 emitter, 22a tip, 23 extraction electrode, 23a opening, 24 cooling device, 25 ion optical system, 26 gas supply source, 26a gas introduction tube, 26m helium atom, 27 power source, 30 Control device, 38 display device, 50 electron beam irradiation system, 50A electron beam, Wa sample, Wb sample, 100,200 composite charged particle beam device

Claims (8)

An ion beam irradiation system including a gas field ion source, and an electron beam irradiation system whose irradiation axis is disposed at an angle of 90 degrees or narrower than 90 degrees with respect to the irradiation axis of the ion beam irradiation system;
A sample stage for supporting the sample at the intersection of the ion beam emitted from the ion beam irradiation system and the electron beam emitted from the electron beam irradiation system;
A gas gun for supplying a functional gas for deposition or etching to a beam irradiation position on the sample;
A composite charged particle beam apparatus comprising:   2. The composite according to claim 1, wherein the ion beam irradiation system is disposed above a vertical direction of the sample stage, and the electron beam irradiation system is disposed to be inclined with respect to the vertical direction. Charged particle beam device.   2. The gas field ion source includes an emitter, an extraction electrode having an opening facing a tip portion of the emitter, and a gas supply unit that supplies a gas to be the ion. Or the composite charged particle beam apparatus of Claim 2.   The composite charged particle beam apparatus according to any one of claims 1 to 3, wherein the ions are helium ions.   A detection device for detecting at least one of secondary charged particles generated from the sample by irradiation of the ion beam or the electron beam and charged particles transmitted through the sample, and displaying an image of the sample based on the output of the detection device 5. The composite charged particle beam apparatus according to claim 1, further comprising:   The composite charged particle beam device according to claim 5, wherein the detection device includes at least one of an electron detector, an ion detector, and a transmission charged particle detector. Irradiating the sample with an ion beam from an ion beam irradiation system including a gas field ion source and processing the sample by supplying a gas to an ion beam irradiation position of the sample;
And observing the sample by irradiating the sample with an electron beam.   The processing observation method according to claim 7, wherein the sample is irradiated with the electron beam from a direction intersecting the ion beam at an acute angle or approximately 90 degrees.

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