JP5020483B2 - Charged particle beam equipment - Google Patents

Description

  The present invention relates to a charged particle beam apparatus, a processing / analysis method, and a method for manufacturing an electronic component / MEMS component, such as a semiconductor wafer (hereinafter referred to as “wafer”).

  In the semiconductor manufacturing process, it is required to produce non-defective products with a high yield and in large quantities. On the other hand, the number of semiconductor manufacturing processes reaches about 100, and if the manufacturing process is advanced without knowing the occurrence of defects in a certain process, a large number of defective products will be generated, resulting in a huge loss. . In order to prevent this, careful inspection is performed for each process, and defects have been discovered, causes have been investigated, and countermeasures have been taken as early as possible.

  In such inspection, measurement of circuit pattern dimensions, inspection of circuit pattern defects, analysis of foreign matters, and the like are performed. Various means for that purpose are prepared and used. For example, as an inspection means, a critical dimension scanning electron microscope (hereinafter referred to as CDSEM) that measures the dimensions of a manufactured circuit pattern, an optical inspection apparatus that uses light for inspection of foreign matter and defects An SEM type inspection device using an electron beam, a nano prober inspection device for inspecting electrical defects such as circuit breaks and short circuits, and the like are used.

  In particular, when a defective part exists in the product, a focused ion beam (hereinafter referred to as “FIB”) device and a scanning electron microscope (hereinafter referred to as “SEM”) are used. .) A microfabrication observation apparatus combined with an apparatus is used. In this microfabrication observation apparatus, a micron-order minute region (hereinafter referred to as “microsample”) including a defective portion is cut out by FIB, and the microsample is extracted and held by a manipulator including a needle-like probe. A method of observing and analyzing the sample by adjusting the position and orientation of the sample and performing additional processing to the optimum shape has been devised and used. This method is described in Patent Document 1 below.

JP 2002-150990 A

  However, since the above-mentioned microfabrication observation apparatus cannot handle both wafers and microsamples with one apparatus, the above-mentioned series of wafers, microsample processing, high resolution analysis, etc. cannot be performed with one apparatus. There is. Further, since a plurality of devices are required, there is a problem that the device becomes complicated or the device becomes large.

  An object of the present invention is to enable a single apparatus to perform sampling from a wafer to high-resolution observation and analysis. Another object of the present invention is to perform high-performance and high-performance processing and analysis on each of the wafer and the minute sample.

As shown in FIG. 1 and FIG. 2, a single apparatus can handle both wafers and micro samples, and a series of wafers, micro samples, and other processes using the above-mentioned FIB, SEM, STEM, etc. Make it possible with the device. Furthermore, by handling the wafer and the micro sample at different positions, it can be configured with an optical system, lens shape, and sample holding mechanism suitable for each sample, enabling high-precision processing and high-resolution observation images. It is possible to provide a single device with high functionality and high performance.
For this purpose, the following means are used.

According to one aspect of the present invention, an electron source that generates an electron beam, a first optical system including the electron source, an ion source provided at a position that generates an ion beam that intersects the electron beam, and the ion A second optical system having a source; first sample mounting means for arranging a micro sample at a first position which is a position where the electron beam and the ion beam intersect or a position in the vicinity thereof; A second sample mounting means for disposing a sample at a second position that is opposite to at least one of the ion source and the electron source from the position; and the first sample mounting means. A first moving means for moving the micro sample from one position to a position that does not prevent passage of the electron beam or the ion beam; and the electron beam or the ion beam to the micro sample arranged at the first position. But A first charged particle detector for detecting reflected electrons or secondary electrons obtained by being irradiated, and either the electron beam or the ion beam from the first position in series with the first beam. A second optical system for detecting reflected electrons or secondary electrons obtained by irradiating the sample placed at the second position with the electron beam or the ion beam; A charged particle detector; and a deflector for guiding the other beam different from the one beam to the third optical system when the micro sample is moved from the first position by the first moving means. , have a, the first optical system comprises a first focusing the electron beam generated from said electron source to said micro-sample that is disposed on a first position of the first sample mounting means An objective lens, 2 of the optical system, characterized by comprising a second objective lens for focusing the ion beam generated from the ion source to the micro-sample that is disposed on a first position of the first sample mounting means A charged particle beam device is provided.

  According to the charged particle beam apparatus, processing, observation, and analysis can be performed using the ion beam and the electron beam at the first position and the second position, respectively. The third optical system can be shared by the electron beam and the ion beam.

  According to the present invention, there is an advantage that a single apparatus can perform from sampling from a wafer to observation and analysis with high resolution. Further, by adopting a configuration suitable for each of the wafer and the minute sample, it is possible to perform high-performance and high-performance processing and analysis on both samples. Therefore, it is possible to save the space for installing the apparatus and improve the economy.

  In the charged particle beam apparatus according to the present invention, a side entry holder is disposed at an intersection in the middle of the optical axis of an ion beam and an electron beam, and a micro sample is mounted on the side entry holder. Here, thin film processing is performed by irradiating an ion beam, and the thin film processing position and progress are confirmed by irradiating an electron beam and observing the shape.

Furthermore, an STEM detector was placed on the opposite side of the sample as viewed from the electron beam source on the extended line of the electron beam axis, the electron beam was irradiated to the thin sample that was made into a thin film, and it was transmitted and emitted to the opposite side of the sample. more to capture the charged particles, it performs STEM analysis of high resolution. Further, EDX analysis is performed by detecting X-rays with an energy dispersive X-ray spectroscopy (hereinafter referred to as “EDX”) detector.

  By shifting the micro sample from the optical axes of the ion beam and the electron beam, each beam passes through the micro sample mounting position. The electron beam is deflected by a deflector and is irradiated on the wafer in a coaxial orbit with the ion beam. Wafer drilling and sampling of small samples are performed by ion beam irradiated to the wafer, and the wafer stage is positioned so that the position of the wafer is aligned and processed by the electron beam, and the incident angle of the electron beam on the wafer changes. Is tilted, and the above-described cross section drilled with an ion beam is observed.

  Hereinafter, a charged particle device according to an embodiment of the present invention will be described with reference to the drawings. First, a charged particle device according to a first embodiment of the present invention will be described. FIG. 1 is a diagram illustrating a configuration example of a charged particle device according to the present embodiment. The ion beam 3 generated from the ion gun 1 is incident on the ion beam converging lens 11 to be converged finely, scanned and deflected by the ion beam deflector 12, and focused on the minute sample 5 by the ion beam objective lens 13. The ion beam 3 is deflected by the ion beam deflector 12 or a separately provided deflector and irradiated to a desired minute region on the minute sample 5.

  The portion irradiated with the ion beam on the micro sample 5 is removed by sputtering. By this etching processing, the sample can be drilled or cut, or thinned.

  On the other hand, the electron beam 4 generated from the electron gun 2 is incident on the electron beam converging lens 14 to be converged finely, scanned and deflected by the electron beam deflector 15, and focused on the minute sample 5 by the electron beam objective lens 16. The electron beam 4 is deflected by the electron beam deflector 15 or a deflector provided separately, and is irradiated onto a desired minute region on the minute sample 5. The micro sample 5 is mounted and held on a micro sample holder 7. The ion beam or electron beam applied to the micro sample 5 mounted on the micro sample holder 7 is applied to the micro sample 10 mounted on the wafer 6 or the wafer holder 9 on which the wafer 6 is mounted. In addition, since the working distance (WD) that is the distance between the objective lens that is the final lens of the charged particle optical system and the sample can be shortened, it is possible to converge more finely. Therefore, there is an advantage that processing, observation, and analysis can be performed with higher resolution.

  A GAE gas nozzle 41, an EDX detector 26, and a charged particle detector (1) 27 are arranged near the micro sample 5. It sprays on the ion beam irradiation part of the micro sample 5 from the GAE gas nozzle 41. FIG. Thus, the ion beam 3 is irradiated while spraying a component gas that promotes etching, whereby the etching processing speed can be increased.

  The minute sample 5 is irradiated with the ion beam 3, charged particles such as secondary electrons generated from the vicinity of the surface are detected by the charged particle detector (1) 27, and detected in synchronization with the scanning deflection of the ion beam deflector 12. By displaying the intensity of the signal on a CRT monitor or the like, it is possible to perform an enlarged observation with a scanning ion microscope (hereinafter referred to as “SIM”) image reflecting the shape of a minute region irradiated with the beam.

  The minute sample 5 is irradiated with the electron beam 4, and charged particles such as secondary electrons and reflected electrons generated from the vicinity of the surface are detected by the charged particle detector (1) 27 and synchronized with the scanning deflection of the electron beam deflector 15. Then, by displaying the intensity of the detected signal on a CRT monitor or the like, it is possible to perform an enlarged observation with an SEM image reflecting the shape of the minute region irradiated with the beam.

  The micro sample 5 is irradiated with the electron beam 4, the X-ray generated from the vicinity of the surface is detected by the EDX detector 26, and the intensity of the detected signal is synchronized with the scanning deflection of the electron beam deflector 15 by a CRT monitor or the like. By displaying the above, it is possible to analyze the EDX image reflecting the composition information of the minute region irradiated with the beam. A STEM detector 30 is disposed on the opposite side of the micro sample 5 when viewed from the electron gun 2 on the extended line of the electron beam axis. The thin sample 5 is irradiated with the electron beam 4, the charged particles emitted to the opposite side of the sample are detected by the STEM detector 30, and the detected signal intensity is synchronized with the scanning deflection of the electron beam deflector 15. Is displayed on a CRT monitor or the like, so that high-resolution STEM analysis reflecting composition information of a minute region irradiated with the beam can be performed.

  When the minute sample holder 7 is removed by operating the minute sample holder 7, the ion beam 3 and the electron beam 4 can pass through the minute sample mounting position. Also, by making the sample holder 7 movable and operating it to shift the micro sample 5 from the axes of the ion beam 3 and the electron beam 4, each beam can pass through the micro sample mounting position. It becomes like this.

  The ion beam 3 that has passed through the minute sample mounting position is incident on the converging lens 17 to be converged finely, scanned and deflected by the deflector 18, and focused on the wafer 6 by the objective lens 19. The ion beam 3 is deflected by the deflector 18 or a separately provided deflector, and is irradiated onto a desired minute region on the wafer. A portion irradiated with the ion beam on the wafer 6 is removed by sputtering. By this etching process, the wafer 6 can be drilled or cut.

  The electron beam 4 that has passed through the minute sample mounting position is deflected by the deflector (1) 21 and the deflector (2) 22 so as to be substantially coaxial with the ion beam 3, and is incident on the converging lens 17 to be converged finely. Then, scanning deflection is performed by the deflector 18 and the wafer 6 is focused by the objective lens 19. The ion beam 3 is deflected by the deflector 18 or a separately provided deflector, and is irradiated onto a desired minute region on the wafer 6.

  The deflector (1) 21 and the deflector (2) 22 apply a positive voltage to one of the electrodes arranged on both sides of the electron beam 4 and apply a negative voltage to the other, thereby moving the electron beam in the traveling direction. The direction of the electron beam 4 is changed by generating a transverse electric field and bending the negatively charged electron beam 4 toward the positive voltage electrode. (See JP-A-56-136446, SURFACE AND INTERFACE ANALYSIS, VOL. 16,105-108 (1990), John Wiley & Sons, Ltd. A New SIMS Instrument for Submicron Microarea Analysis.)

  The converging lens 17, the deflector 18, and the objective lens 19 are commonly used for the case of irradiating the ion beam 3 and the case of irradiating the electron beam 4. (Refer to Japanese Patent No. 2714009.)

  Near the beam irradiation position of the wafer 6, a charged particle detector (2) 29, a micro sampling probe 35, a GAE gas nozzle 42, and a GAD gas nozzle 43, which will be described later (see FIG. 7), are arranged.

  As in the case of the micro sample 5, the wafer 6 is irradiated with the ion beam 3, charged particles such as secondary electrons generated from the vicinity of the surface are detected by the charged particle detector (2) 29, and the deflector 18 In synchronization with the scanning deflection, the intensity of the detected signal is displayed on a CRT monitor or the like, so that a magnified observation with a SIM image reflecting the shape of a minute region irradiated with the ion beam 3 can be performed.

  As in the case of the micro sample 5, the wafer 6 is irradiated with the electron beam 4, and charged particles such as secondary electrons and reflected electrons generated from the vicinity of the surface are detected by the charged particle detector (2) 29 and deflected. By displaying the detected signal intensity on a CRT monitor or the like in synchronization with the scanning deflection of the device 18, it is possible to perform an enlarged observation with an SEM image reflecting the shape of the minute region irradiated with the electron beam 4. Similarly to the above micro sample, the ion beam 3 is irradiated to the wafer 6 while the gas of the component that accelerates the etching is blown from the GAE gas nozzle 42, thereby speeding up the etching process. By irradiating the ion beam 3 to the ion beam irradiation part of the wafer 6 from the GAD gas nozzle 43 while irradiating the ion beam 3 while spraying the gas, it is possible to form a film in a desired region, fill a hole, Adhesion to the extracted sample is possible.

  The micro sample 10 of the wafer 6 is cut out by the ion beam 3 irradiated to the wafer 6, the cut sample 10 is adhered to the micro sampling probe 35 by the GAD, extracted, transported to the micro sample holder 9, and cut out. The micro sample 10 is cut out by GAD and mounted on the micro sample holder 9, and the micro sampling probe 35 is cut by the ion beam 3. By taking out the micro sample 10 with the cut micro sample holder 9 out of the apparatus, the micro site of the wafer 6 can be sampled. Thereafter, the extracted microsample 10 can be analyzed with a high-resolution SEM, or after thin film processing with FIB, high-resolution analysis can be performed with STEM, TEM, or the like.

  For an example of a method for sampling a minute part from the wafer 6, reference can be made to the republished patents WO99-05506 and JP2002-150990 (hereinafter referred to as “microsampling function”). The wafer 6 is held by a wafer drive stage 8, and the irradiation position and the incident angle of the beams 3 and 4 are selected by moving and tilting relative to the beams 3 and 4 by the wafer drive stage 8. Can do.

  FIG. 2 is a diagram illustrating an example of an analysis method according to the present embodiment. In FIG. 2, the optical system shown in FIG. 1 is simplified as a FIB ion optical system 201, an SEM electron optical system 202, and an ion beam / electron beam shared optical system 205. Here, a wafer stage on which the wafer 6 is mounted and a holder 7 for a minute sample are provided. In the micro sample mounting portion 7a of the micro sample holder 7, the micro sample 5 can be thinned by an ion beam, SEM observation by electron beam, and STEM observation. Either or both of the ion beam and the electron beam are deflected so that the sample positions of both the wafer 6 and the minute sample 5 can be irradiated. Here, the micro sample 5 is irradiated with a beam so that the micro sample 5 can be arranged in the middle of the beam axis (position ahead of the arrow AR3). On the other hand, when the minute sample 5 is shifted from the beam axis, the beam passes and can be irradiated onto the wafer 6 (the original position of the arrow AR1). As shown by the arrow AR1, the minute sample 6 is cut out from the wafer 6, mounted on the minute sample mounting portion 7a of the holder 7 for minute samples (arrow AR2), and the position where the beam can be irradiated to the minute sample 5 in the middle of the beam axis. The minute sample 5 can be moved to the position (the position ahead of the arrow AR3). It is possible to control the operation condition of the optical system to be switched in accordance with the operation mode of each combination of FIB and SEM, and a small sample and a wafer.

  FIG. 3 is a chart showing the beam path. The beam path in each of the combination of the beam based on FIB, SEM, STEM, etc., the mode of the detector, the sample is a micro sample, a wafer, and a cut micro sample. FIG. Where appropriate, reference is also made to FIG.

  3A is a diagram showing an example in which FIB is used for a minute sample. As shown in FIG. 3, when FIB is used in minute sample 5, ion gun 1 and FIG. The ion beam converging lens 11, the ion beam deflector 12, and the ion beam objective lens 13 shown in FIG. The electron beam 4 stops the operation of the electron gun 2 or largely deflects the electron beam 4 with the electron beam deflector 15 shown in FIG. 1 or another deflector provided so as not to reach the sample (dashed line) reference).

  As shown in (b) and (c), when an SEM or STEM is used for a small sample, the electron gun 2, the electron beam converging lens 14, the electron beam deflector 15, the electron beam objective shown in FIG. The lens 16 is operated to irradiate the minute sample 5 with the electron beam 4. The ion beam 3 stops the operation of the ion gun 1 so as not to reach the sample. When irradiating the wafer 6 with a beam, the minute sample 5 is removed or shifted from the beam axis so that the beam passes through the minute sample mounting position.

  (D) and (f) are intended for wafers and cut-out microsamples. When the FIB is used for the wafer 6 or the cut out small sample 10 (d), the ion gun 1, the ion beam converging lens 11, the converging lens 17, the deflector 18, and the objective lens 19 shown in FIG. The beam 3 is irradiated onto the wafer 6 or the cut out micro sample 10. At this time, the operation of the ion beam deflector 12 and the ion beam objective lens 13 is stopped so that the ion beam is not scanned and deflected in the vicinity of the minute sample mounting position.

  The electron beam 4 stops the operation of the electron gun 2 or largely deflects the electron beam by the electron beam deflector 15 or a separately provided deflector so as not to reach the sample.

  As shown in (e), when the SEM is used with the wafer 6 or the cut out small sample 10, the electron gun 2, the electron beam converging lens 14 shown in FIG. 1, the deflector (1) 21, and the deflector (2) 22 are used. Then, the converging lens 17, the deflector 18 and the objective lens 19 are operated to irradiate the wafer 6 or the cut out minute sample 10 with the electron beam 4.

  At this time, the operation of the electron beam deflector 15 and the electron beam objective lens 16 is stopped so that the electron beam is not deflected or focused in the vicinity of the minute sample mounting position. The ion beam 3 stops the operation of the ion gun 1 so as not to reach the sample.

  Next, a procedure for analyzing the inside of the vicinity of the wafer surface by the charged particle beam apparatus according to the present embodiment will be described. In a semiconductor manufacturing process, a portion where the inside of a wafer is desired to be analyzed is often a position pointed out by a defect inspection apparatus that a defect may exist. Information on the position where the detected defect may exist is output from the defect inspection apparatus. The analysis position is searched based on this position information. At this time, the analysis position is searched using SEM image information reflecting the shape of the surface obtained by irradiating the wafer surface with the electron beam together with the dimension position information. Of course, the analysis position may be searched without using the position information provided from the defect inspection apparatus or the like.

  FIG. 4 is a diagram related to hole processing and cross-sectional observation on the wafer 6 surface. In order to analyze the inside of the vicinity of the surface of the wafer 6, two methods can be mainly used. In the first method, as shown in FIG. 4, drilling is performed with the ion beam 3 at a position adjacent to the portion to be analyzed of the wafer 6 in FIG. 4 (a), and the portion to be analyzed is exposed on the hole wall portion. Then (in the figure, processing is performed into a triangular prism shape up to the broken line portion), and as shown in FIG. 4B, the processed wall surface is irradiated with the electron beam 4 and analyzed using an SEM image or the like.

  In the charged particle beam apparatus according to the present embodiment, since the incident angles of the ion beam 3 and the electron beam 4 on the wafer are the same, a position where the electron beam 4 can be irradiated onto the hole wall as shown in FIG. Tilt the wafer up to.

  The second method will be described with reference to FIGS. As shown in FIG. 5 and FIG. 6, a portion to be analyzed is cut out as a micro sample, and high resolution analysis is performed with the micro sample analysis function. Cutting out as a micro sample can be performed by the above-mentioned “micro sampling function”.

  First, as shown in FIG. 5A, a sample 10 is cut out using a microsampling probe 35 at a position adjacent to a portion of the wafer 6 to be analyzed. As shown in FIG. 5 (b), the cut out micro sample 10 is mounted on the cut out micro sample holder 9.

  As shown in FIG. 6, the cut out micro sample 10 is attached to the tip of the above described micro sample holder 7 which is different from the cut out micro sample holder 9, and placed at the micro sample mounting position (see FIG. 1) (FIG. 2). reference). With regard to the cut out micro sample 10, the micro sample 5 will be referred to as the micro sample 5 when it is arranged at the micro sample mounting position, and the following description will be given. As shown in FIGS. 6A and 6B, the thin film is processed by irradiating the ion beam so that the cross section to be analyzed is aligned in parallel with the optical axis of the ion beam 3. At this time, accurate processing can be performed by processing while confirming the processing position and the progress of the processing with an SEM.

  Next, by operating the micro sample holder 7 as shown in FIG. 6C, the cross section of the thin micro sample 5 is directed in the axial direction of the electron beam 4 to irradiate the electron beam 4 to obtain a high-resolution STEM. Perform analysis, EDX analysis, etc.

The advantages of the charged particle beam apparatus according to this embodiment are listed below.
1) By crossing the optical axis of the ion beam and the optical axis of the electron beam and mounting a small sample near the intersection, thin film processing and STEM analysis are performed at the same mounting position by simply changing the direction of the sample. be able to. Therefore, as compared with the case where thin film processing and STEM analysis are performed with different apparatuses, there is no need to transfer the sample to another mounting position after the thin film processing and before STEM analysis is performed. Sexuality is improved.

  2) By crossing the optical axis of the ion beam and the optical axis of the electron beam and mounting a micro sample near the intersection, the beam is irradiated to the micro sample mounted on the wafer or wafer holder. The working distance (WD) can be shortened. Therefore, processing, observation, and analysis with higher accuracy can be performed.

  3) By using a dedicated holder for small samples, the vibration resistance performance of the small samples is improved and high-precision processing, observation, and analysis can be performed compared to mounting a small sample on the wafer stage. There are advantages.

  In addition, by placing the optical axis of the ion beam incident on the micro sample mounting position and the optical axis of the electron beam at an acute angle, the orientation of the sample can be changed from the state of thin film processing compared to the case where the optical axis is coaxial or nearly vertical. Both the upper surface and the cross section of the sample can be observed simultaneously by SEM without changing the above. Therefore, the thickness of the remaining film and the shape of the cross section can be confirmed at the same time, and the operation of changing the direction of the sample is not required between the thin film processing and the processing status confirmation processing, thereby improving the operability.

  4) By separating the optical axis of the ion beam incident on the minute sample mounting position and the optical axis of the electron beam, the ions that have passed through the STEM detector through the minute sample mounting position compared to the case where they are arranged coaxially. There is no need to place them on the trajectory of the beam and electron beam. Therefore, there is no need to arrange the STEM detector on the electron beam trajectory or shift from the trajectory every time the STEM observation is performed, and there is an advantage that a device with good operability can be provided.

  In addition, by arranging the STEM detector in a fixed manner, it is possible to save the trouble of providing a mechanism for operating the STEM detector close to a minute sample every time STEM observation is performed.

  Further, the structural design is facilitated by arranging the STEM detector in a place having a relatively large space compared to a narrow place such as the lower part of the sample chamber or on the beam trajectory of the electron optical system. Further, by disposing the STEM detector in a place having a relatively large space, a mechanism for changing the distance between the minute sample and the STEM detector during STEM analysis can be easily made.

  5) A small and economical apparatus can be provided by providing a shared portion in which the optical axis of the ion beam incident on the wafer and the optical axis of the electron beam are arranged coaxially. Particularly in a clean room, it is more important in terms of capital investment cost to reduce the size in the horizontal direction, that is, the occupied floor area, than the size in the height direction of the apparatus. Therefore, the apparatus is larger in the height direction than a general FIB-SEM, but it is not larger in the lateral direction, so that the size can be reduced.

  6) By arranging the optical axis of the ion beam incident on the wafer and the optical axis of the electron beam coaxially, the incident angles of the ion beam and the electron beam to the wafer become the same, so that compared to the case where they are arranged individually. Thus, observation and processing can be performed at the same viewing angle, and a portion that cannot be seen due to a difference in viewing angle or an uneven portion is not generated, and an apparatus with good operability can be provided. Further, since the wafer can be brought close to the objective lens, the WD can be shortened, so that high-resolution observation and processing can be performed.

  7) Since the FIB and SEM functions for wafers and the FIB, SEM and STEM functions for small samples are equipped, a single device can be used for sample extraction from wafers, thin film processing with FIB, and high resolution analysis with STEM. Can be done in a space-saving and economical.

  8) With a configuration suitable for each of the wafer and the minute sample, it becomes possible to perform high-performance and high-performance processing and analysis on both samples. For the wafer, since the WD can be shortened by sharing the electron beam and ion beam objective lenses, high-precision observation, processing, and analysis can be performed. By using a small sample holder for a small sample, the WD can be shortened for the minute sample, and high-precision observation, processing, and analysis can be performed because the earthquake resistance is improved.

  9) In a manufacturing process in which a sample is processed to form an electronic component or a MEMS component, the results of inspection and analysis of the sample by the observation and processing method of the present invention are used to suppress the occurrence of defects and defects. Yield can be improved by adjusting factors that control machining.

  In the manufacturing process, after an optional step, the sample is inspected and analyzed by the observation and processing method of the present invention, and then the sample is returned to an optional step or the step subsequent to the optional step to continue the manufacturing process. Thus, the sample can be used for evaluation without being wasted. In addition, by applying this observation and processing method to inspection and analysis of manufacturing electronic parts and the like, it is possible to realize a new economical inspection and analysis method and manufacturing method of fine parts such as electronic parts and MEMS parts. it can.

  Below, the modification of the 1st Embodiment of this invention is demonstrated, referring drawings. The modifications shown below relate to the arrangement of the optical system. A modification will be described while comparing with the first embodiment. In the following drawings, for the sake of simplicity, the optical systems 11, 12, and 13 in FIG. 1 are denoted by reference symbol A, the optical systems 14, 15, and 16 are denoted by reference symbol B, and the optical systems 17, 18, and 19 are denoted by reference symbol A. This is indicated by symbol C. The description will be given with reference to FIG.

(1) In the charged particle beam apparatus according to the first embodiment, the position after the electron beam 4 passes through the intersection of the electron beam 4 and the ion beam 3 through the deflectors 21 and 22 that change the trajectory of the electron beam 4. However, in the charged particle beam apparatus according to the first modification, the positions of the deflectors 21 and 22 are set near or at the intersection of the electron beam 4 and the ion beam 3 as shown in FIG. It is characterized in that it is arranged before passing through. It is possible to use only one stage (21) of deflectors. In this case, since it is difficult to mount in space, it is preferable to use a small deflector.

(2) In the charged particle beam apparatus according to the first embodiment, the optical axes of the electron beam 4 and the ion beam 3 that irradiate the minute sample 5 are arranged so as to have an acute angle on the beam source side. In the charged particle beam apparatus according to the second modified example, the optical axes of the electron beam 4 and the ion beam 3 are arranged so as to be substantially orthogonal as shown in FIG. By arranging in this way, vertical SEM and STEM analysis of the cross section can be performed without tilting the micro sample 5 after processing with the ion beam 3. In this method, since only the upper surface can be observed when confirming the processing state with the SEM, the remaining thickness of the processing cannot be confirmed by observing the upper surface of the sample without tilting the sample. The left figure shows how the minute sample 5 is processed by the ion beam 3, and the right figure shows how the minute sample is observed by the electron beam.

(3) In the charged particle beam apparatus according to the first embodiment, the optical systems of the electron beam 4 and the ion beam 3 that irradiate the minute sample 5 are arranged separately. As shown in FIG. 10 (3), the third modification is characterized in that an optical system other than the electron gun or an optical system including the electron gun is shared and made coaxial. In this way, the optical system components can be further reduced. The left figure is an example in which the ion beam and electron beam light sources are at the same position, and the right figure is an example in which the ion beam and electron beam light sources are at different positions.

  However, since the STEM detector 30 is arranged on the optical axis, an additional work of arranging the STEM detector 30 on the orbit of the electron beam or shifting from the orbit every time the STEM observation is performed. In order to avoid this, a deflector that can be switched so as to be deflected only at the time of STEM observation is arranged after the micro sample 5, and the trajectory of the charged particle beam transmitted and emitted from the micro sample is bent and detected by the STEM detector. It is good also as arrangement to do.

(4) In the charged particle beam apparatus according to the first embodiment, as shown in FIG. 1, the electron beam 4 and the ion beam 3 are arranged so as to enter the wafer 6 perpendicularly. ) If the entire optical system is arranged so as to be inclined with respect to the wafer 6, the sample can be cut out from the wafer 6 without tilting the wafer 6 if the beam is arranged obliquely. There is an advantage of becoming.

(5) In the charged particle beam apparatus according to the first embodiment described above, the beams 3 and 4 immediately before irradiating the wafer 6 are coaxial, but this is shown, for example, as shown in FIG. By disposing the optical system separately so as not to be coaxial, SEM observation of the hole processing cross section can be performed without tilting the wafer 6. However, there is a problem that the number of components and parts of the optical system increases and the apparatus becomes larger. 11 (5) is an example in which the ion beam light source 1 is provided in the normal direction with respect to the beam irradiation position on the surface of the wafer 6, and the right diagram in FIG. 11 (5) is an ion diagram. In the example, both the beam light source 1 and the electron beam light source 3 are provided at positions deviating from the normal direction of the beam irradiation position. In the latter case, a deflector is required for both beams.

(6) In the charged particle beam apparatus according to the first embodiment, an example in which only the electron beam 4 is deflected is shown, but both the electron beam 4 and the ion beam 3 are placed in front of the micro sample 5 (on the light source side). By arranging a deflector (not shown) so that it can be deflected at the position of, the beam trajectory is switched by the deflectors 21a and 21b without the micro sample 5 being removed or shifted from the beam irradiation position. It can be switched to irradiate beams 3 and 4.

(7) In the charged particle beam apparatus according to the first embodiment described above, the electron beam 4 and the ion beam 3 are arranged so that both the electron beam 4 and the ion beam 3 can be applied to the mounting position of the micro sample 5. Is arranged so as to irradiate only the wafer 6 without irradiating the mounting position of the wafer, thin film processing is performed by the cut sample holder 10 next to the wafer 8, and only the SEM optical system detects the minute sample 5 and STEM in the middle of the beam. It is also possible to mount the device 30. With such a configuration, there is an advantage that any beam optical axis need not be deflected and a deflector becomes unnecessary.

(8) In the charged particle beam apparatus according to the first embodiment, both the electron beam 4 and the ion beam 3 are used. Incidentally, as shown in FIG. 12 (8), even in an apparatus that uses only the electron beam 4, a micro sample 5, a STEM detector 30, and a deflector (not shown) are arranged in the middle of the electron beam 4. . By doing so, there is a convenience that both the wafer 6 and the minute sample 5 can be observed and analyzed.

(9) In the charged particle beam apparatus according to the first embodiment, the electron beam 4 and the ion beam 3 incident on the wafer 6 after passing through the mounting position of the micro sample 5 are focused as main optical system components. A lens, deflector, and objective lens are used. In this modified example, the converging lens is deleted from the configuration of FIG. 1 and only the deflector and the objective lens are used (the left diagram), or the converging lens and deflector are deleted from the configuration of FIG. If only this is used (right figure), the optical system components can be further reduced, so that the configuration can be simplified, the apparatus can be downsized, and the cost can be reduced.

(10) Compared to the charged particle beam apparatus according to the first embodiment, as shown in FIG. 13 (10), the electron beam objective lenses E1 and E2 of the minute sample portions 5 and 7 are By arranging the objective lens magnetic pole on the electron gun side and the opposite side of the sample in the axial direction, and shortening the WD, it becomes a so-called in-lens type objective lens that can converge the electron beam applied to the sample more finely. Higher SEM and STEM observation and analysis can be performed. When the magnetic pole of the objective lens is in-lens type and interferes with the objective lens of the ion beam, it is preferable that the electron beam and the ion beam are arranged close to a right angle as in the example described above. (See the upper and middle figures in FIG. 13 (10)).

(11) In the charged particle beam apparatus according to the first embodiment, the electron beam 4 and the ion beam 3 intersect at the position where the wafer 6 or the minute sample 5 is irradiated. However, the wafer 6 or the minute sample 5 may be moved by the distance between the electron beam 4 and the ion beam 3 to align the processing, observation, and analysis locations. .

  Next, a charged particle beam device according to a second embodiment of the present invention will be described with reference to the drawings. The charged particle beam apparatus according to the present embodiment has a configuration capable of analyzing a wafer and a micro sample in an apparatus arranged in one casing.

  As shown in FIG. 7A, the ion beam source 202, the electron beam source 201, and the microsampling probe 35 are arranged at a position close to the wafer 6. A wafer stage having a plurality of drive tables and a drive mechanism 702 is housed in a housing 701, and a cut-out micro sample holder 703 for mounting a micro sample 10 cut out from the wafer 6 is mounted next to the wafer 6 placed thereon. It is arranged. In the micro sample holder 703, thin film processing and STEM analysis are performed. Further, the STEM detector 30 is disposed on the bottom of the sample chamber 701 below the stage.

  In FIG. 7B, in the stage coordinates using the STEM, a space through which the sample transmission electron Y can pass is formed between the cut out micro sample 10 and the STEM detector 30.

  In the configuration shown in FIG. 7, the apparatus can be compactly formed, and the beam emitted from the SEM column and the FIB column is irradiated to the minute sample mounted on the wafer drive stage, and the STEM detector is provided below the sample. Therefore, there is an advantage that it is not necessary to replace the minute sample on the minute sample holder for STEM observation.

  Next, a charged particle beam device according to a third embodiment of the present invention will be described with reference to the drawings. The apparatus shown in FIG. 8 is characterized in that it has the SEM / FIB shared column 205 in the configuration shown in FIG. As shown in FIGS. 8A and 8B, the drive table and the drive mechanism 702 are attached to a curved stand 705. As shown in FIG. 7B, in the stage coordinates using the STEM, a space through which the sample transmission electron Y ′ can pass is formed between the cut out micro sample 10 and the STEM detector 30.

  According to the charged particle apparatus of the present embodiment, STEM observation is possible on the wafer stage, and high-resolution processing and analysis are possible by using a common column. In addition, the apparatus can be made compact.

  Next, a charged particle beam device according to a modification of the third embodiment of the present invention will be described with reference to the drawings.

The apparatus shown in FIG. 9 is characterized in that, in the apparatus shown in FIG. 8, the STEM detector 30 is reduced in size and is incorporated in a stage on which the wafer 6 is placed in the housing 701. In this case, as shown in FIG. 9 (b), by the beam to the micro sample 10 moves the stage 702 c to the position to be irradiated, STEM observed by STEM detector 30 provided below the micro sample 10 Is possible. Even in this case, the structure is simplified. When the distance between the micro sample and the STEM detector is short, the STEM detector can be mounted on the lower stage table.

In addition, the description of the abbreviation used in this specification is shown below.
FIB: Focused Ion Beam Focused ion beam system
SEM: Scanning Electron Microscope
TEM: Transmission Electron Microscope
STEM: Scanning Transmission Electron Microscope
SIM: Scanning Ion Microscope
EDX: Energy Dispersive X-ray Spectroscopy
MEMS: Micro Electro Mechanical Systems Micromachine

  The present invention can be used for a charged particle beam apparatus for processing and observing a semiconductor integrated circuit or the like. In addition, in the field of fine structure use such as magnetic recording / reproducing heads, magneto-optical recording / reproducing heads, MEMS, etc., the present invention can be applied to inspection, analysis, production of multilayer thin film structures and fine structures on the order of nm to micrometer, and apparatuses used therefor.

It is a figure which shows the example of 1 structure of the charged particle apparatus by the 1st Embodiment of this invention. It is a figure which shows an example of the analysis method by this Embodiment. FIG. 5 is a chart showing beam paths, illustrating a beam path when each of a combination of a beam based on FIB, SEM, STEM, etc., a detector mode, and a sample is a micro sample, a wafer, or a cut micro sample; It is. It is a figure regarding the hole processing to a wafer part, and cross-sectional observation. It is a figure which shows the micro sample cutting-out process from a wafer. It is a figure which shows the thin film processing of a micro sample, SEM, and a STEM analysis process. It is a figure which shows the example which mounts a STEM detector in a sample chamber. It is a figure which replaces with the structure shown in FIG. 7, and has a SEM / FIB shared column. FIG. 9 is a diagram showing a configuration in which the STEM detector is made small in size and built in a stage on a wafer on which a wafer is placed in the apparatus shown in FIG. 8. FIGS. 10 (1) to (4) are diagrams showing a modification of the first embodiment. FIGS. 11 (5) to (7) are diagrams showing a modification of the first embodiment. FIGS. 12 (8) and 12 (9) are diagrams showing a modification of the first embodiment. (10) is a diagram showing a modification of the first embodiment.

Explanation of symbols

1 ion gun, 2 electron gun, 3 ion beam, 4 electron beam, 5 micro sample, 6 wafer, 7 micro sample holder, 8 wafer drive stage, 9 cut micro sample holder, 10 cut micro sample, 11 ion beam focusing lens, 12 ion beam deflector, 13 ion beam objective lens, 14 electron beam converging lens, 15 electron beam deflector, 16 electron beam objective lens, 17 converging lens, 18 deflector, 19 objective lens, 21 deflector 1, 22 deflector 2, 23 EXB filter, 26 EDX detector, 27 Charged particle detector 1, 28 Charged particle detector 2, 29 Charged particle detector 3, 30 STEM detector, 35 Microsampling probe, 41 GAE gas nozzle, 42 GAE gas nozzle, 43 GAD gas nozzle, 201 FIB ion optics, 202 SEM electron optics, 203 FIB dedicated ion optics, 204 STEM only Electron optical system, 205 Ion beam / electron beam shared optical system, 701 Sample chamber, 702 Wafer drive stage, 703 Cut out small sample holder

Claims (7)

An electron source for generating an electron beam and a first optical system having the electron source;
An ion source provided at a position where an ion beam intersecting the electron beam is generated and a second optical system having the ion source;
First sample mounting means for arranging a micro sample at a first position which is a position where the electron beam and the ion beam intersect or a position in the vicinity thereof;
Second sample mounting means for disposing a sample at a second position that is opposite to at least one of the ion source and the electron source from the first position;
First moving means for moving the first sample mounting means from the first position to a position where the micro sample does not hinder the passage of the electron beam or the ion beam;
A first charged particle detector that detects reflected electrons or secondary electrons obtained by irradiating the electron beam or the ion beam to a micro sample disposed at the first position;
A third optical system for guiding either the electron beam or the ion beam from the first position to the second position in series;
A second charged particle detector for detecting reflected electrons or secondary electrons obtained by irradiating the sample arranged at the second position with the electron beam or the ion beam;
A deflector for guiding the other beam different from the one beam to the third optical system when the micro sample is moved from the first position by the first moving means;
Have
The first optical system includes a first objective lens that focuses the electron beam generated from the electron source on the minute sample disposed at the first position of the first sample mounting unit,
The second optical system includes a second objective lens that focuses the ion beam generated from the ion source onto the minute sample disposed at the first position of the first sample mounting unit. Charged particle beam device characterized by the above.   The charged particle beam apparatus according to claim 1, further comprising a STEM detector disposed at a position where the electron beam passes through the minute sample.   The charged particle beam apparatus according to claim 1, wherein an SEM image or a SIM image can be obtained by the first charged particle detector.   4. The apparatus according to claim 1, further comprising a second moving unit that moves the first sample mounting unit between the first position and the second position. 5. The charged particle beam apparatus described.   The charged particle beam apparatus according to any one of claims 1 to 4, wherein the first sample mounting means includes a minute sample tilt stage. The charged particle beam apparatus according to any one of claims 1 to 5, wherein the micro sample is a sample formed by processing the sample with the ion beam. An electron source for generating an electron beam;
An ion source provided at a position for generating an ion beam crossing the electron beam;
First sample mounting means for arranging a micro sample at a first position which is a position where the electron beam and the ion beam intersect or a position in the vicinity thereof;
Second sample mounting means for disposing a sample at a second position that is opposite to at least one of the ion source and the electron source from the first position;
First moving means for moving the first sample mounting means from the first position to a position where the micro sample does not hinder the passage of the electron beam or the ion beam;
A first charged particle detector disposed at a beam reflection position from the first position;
A second charged particle detector disposed at a beam reflection position from the second position;
A deflector for guiding one of the electron beam and the ion beam to the second position when the micro sample is moved from the first position by the first moving means;
Have
The first optical system including the electron source has a first objective for focusing the electron beam generated from the electron source on the micro sample arranged at the first position of the first sample mounting means. With a lens,
The second optical system including the ion source has a second objective for focusing the ion beam generated from the ion source on the micro sample arranged at the first position of the first sample mounting means. A charged particle beam apparatus comprising a lens.

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