JP2002148159A - Sample preparation method and device for it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sample preparation method and a device for it for separating or separatingly preparing a minute sample including a desired specific region from a sample such as a semiconductor wafer and an electronic part like a device without tilting a sample stage for the purpose of minute region analysis, observation, or measurement. SOLUTION: In this sample preparation method, an objective minute sample periphery is removed by irradiating the sample with a focused ion beam radiated to the sample surface at an angle of less than 90 degrees. Subsequently, the sample stage is turned around the vertical line to the sample surface, and the sample is irradiated while the focused ion beam irradiation angle to the sample surface is fixed. In this way, the minute sample is separated or separatingly prepared.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for separating or preparing a minute sample including a desired specific region from a sample such as an electronic component such as a semiconductor wafer or a device using a focused ion beam, and analyzing the minute region. The present invention relates to a sample preparation method and a sample preparation device for observation and measurement.

[0002]

2. Description of the Related Art In the production of semiconductor devices typified by dynamic random access memories, semiconductor devices such as microprocessors and semiconductor lasers, and electronic components such as magnetic heads, high yield production is required. That is, a decrease in the product yield due to the occurrence of a defect causes deterioration in profitability. Therefore, early detection and early countermeasures of defects, foreign matter, and processing defects that cause defects become major issues. For example, in semiconductor device manufacturing sites, efforts have been focused on finding defects through careful inspection and analyzing the causes of their occurrence. In an actual electronic component manufacturing process using a wafer, a wafer in the middle of the process is inspected, and a cause of an abnormal portion such as a defect of a circuit pattern or a foreign matter is investigated, and a countermeasure method is examined.

[0003] Usually, a high-resolution scanning electron microscope (hereinafter abbreviated as SEM) is used to observe the fine structure of a sample. However, with high integration of semiconductors, an object cannot be observed at the resolution of SEM. Therefore, a transmission electron microscope (hereinafter abbreviated as TEM) having higher observation resolution is used instead of the SEM.

[0004] Conventional TEM sample preparation involves cutting the sample into small pieces by cleaving or cutting. When the sample is a wafer, the wafer must be cut in most cases.

Recently, a sample is irradiated with an ion beam,
There is an example in which a processing method of a minute region using an action of emitting particles constituting the sample from the sample by a sputtering action, that is, a focused ion beam (hereinafter abbreviated as FIB) processing is used. First, a pellet such as a wafer is cut out from a sample such as a wafer into a sub-mm-thick strip-shaped pellet including a region to be observed. Next, a part of this strip-shaped pellet is processed into a thin wall shape by FIB to obtain a TEM sample. The feature of the TEM observation sample processed by FIB is that a part of the test piece is processed into a thin film having a thickness of about 100 nm for TEM observation. According to this method, a desired observation portion can be positioned and observed with a precision of a micrometer level, but the wafer must also be cut.

As described above, monitoring the result of a certain process during the manufacture of a semiconductor device or the like has a great advantage in terms of yield management. However, in the sample preparation as described above, the wafer is cut and the wafer is cut. The debris is discarded without proceeding to the next process. Especially in recent years, wafers
2. Description of the Related Art In order to reduce the manufacturing cost of a semiconductor device, the diameter of the semiconductor device is increasing. That is, the number of semiconductor devices that can be manufactured with one wafer is increased, and the unit price is reduced. However, on the contrary, the price of the wafer itself becomes expensive, the added value increases as the manufacturing process progresses, and the number of semiconductor devices lost by discarding the wafer also increases. Therefore, the conventional inspection method involving the division of the wafer is very uneconomical.

On the other hand, there is a method in which a sample can be manufactured without dividing a wafer. This method is disclosed in
No. 5,527,721, entitled "Sample Separation Method and Analysis Method of Separated Sample Obtained by This Separation Method" (Known Example 1). In this method, as shown in FIG. 2, first, the posture of the sample 2 is maintained such that the FIB 1 irradiates the surface of the sample 2 at right angles, and the FIB 1 is scanned on the sample in a rectangular shape. Is formed (FIG. 2A). Next, the sample 2 is inclined to form a bottom hole 8. The tilt angle of the sample 2 is changed by a sample stage (not shown) (FIG. 2B). Change the posture of sample 2 so that the surface of sample 2 is FIB1
Then, the sample 2 is set so as to be perpendicular to the above, and a notch groove 9 is formed (FIG. 2C). By driving a manipulator (not shown), the tip of the probe 3 at the tip of the manipulator is brought into contact with a portion for separating the sample 2 (FIG. 2).
(d)). The deposition gas 5 is supplied from the gas nozzle 10 and FI
A region including the tip of the probe 3 is locally irradiated with B1 to form an ion beam assisted deposition film (hereinafter abbreviated as a deposition film 4). The separated portion of the sample 2 in contact with the tip of the probe 3 is connected by a deposition film 4 (FIG. 2).
(e)). Cut out the remaining part with FIB1 (Fig. 2
(f)), micro sample 6 which is a sample separated from sample 2
Cut out. The separated sample 6 thus cut out is supported by the connected probe 3 (FIG. 2 (g)). The micro sample 6 is processed by the FIB 1 and a region to be observed is processed into a wall to be a TEM sample (not shown). This is a method of separating a minute micro sample including a desired analysis region from a sample such as a wafer by using FIB processing and a means for transporting the minute sample. The micro sample separated by this method can be analyzed by introducing it into various analyzers.

A similar sample preparation method is also disclosed in Japanese Patent Application Laid-Open No. 09-196213, entitled "Microsample preparation apparatus and method" (known example 2). In this method, first, as shown in FIG. 9, FIB1 is irradiated to form marks 403 and 404 for target position identification.
Thereafter, rectangular holes 401 and 402 are formed in the sample 2 on both outer sides thereof (FIG. 9A). Next, the rectangular groove 406 is formed by FIB1.
Is formed (FIG. 9B). Next, the sample stage is tilted to irradiate the sample surface with the FIB 1 obliquely, thereby forming an oblique groove 408, and forming an extracted sample 407 connected to the sample 4 only by a part of the support portion 405 (FIG. 9). (c)). The inclination of the sample stage is returned, and the probe 3 is controlled by the probe control device, and is brought into contact with a part of the extracted sample 407. The support portion 405 of the extirpated sample is to be cut by FIB later, but it is desirable to cut the support portion 405 in a short time when a probe drift or the like is taken into consideration. Therefore, it is necessary to reduce the volume of the support portion. For this reason, since the support part 405 may be broken by the contact of the probe 3, the contact is performed by using the above-described probe control method while minimizing damage. The contacted probe 7 and the extracted sample 407 are
(FIG. 9D). Next, the support portion 405 is cut by the FIB 1 (FIG. 9E). Thus, the extracted sample 407 is cut out, and the probe 3 is raised and extracted by the probe driving device (FIG. 9 (f)). Next, the cut out sample 407 is brought into contact with a groove 411 formed in the sample holder (FIG. 9 (g)). The contact at this time needs to be performed at a sufficiently low speed so that the extracted sample 407 is not broken or the extruded sample 407 is detached and disappears at the deposition film 409, and the above-described contact method is required. After such contact, both are fixed using the deposition film 412 (FIG. 9 (h)). After the fixation, the probe 3 is irradiated with FIB, sputtered, and the probe is separated from the extracted sample 407 (FIG. 9 (i)). When a TEM sample is used, the FIB 1 is irradiated again, and finally the observation region 410 is thinned to a thickness of about 100 nm or less (FIG. 9 (j)). When used for the preparation of other analysis and measurement samples, processing to thin the observation area (Fig. 9 (j))
Is not necessary.

The above is an example in which a method of taking out a micro sample by using a sample preparation apparatus is adopted. However, the shape of the micro sample is processed by the sample preparation apparatus, the substrate is taken out from the sample preparation apparatus, and the sample is separated in the air. There is also a method of taking out a micro sample by the mechanism described above. For example, Material Resea
From pages 19 to 27 of rch Society, Symposium Proceeding vol. 480, LA Giannuzzi et al., Focused Ion Beam
Milling and Micromanipulation Lift-Out for Site S
pecific Cross-Section TEM Specimen Preparation ''
This is described in a paper entitled (known example 3). Proceedings of the 22 nd International Symposiu
m for Testing and Failure Analysis, pages 199 to 205, LR Herlinger et al.'s TEM Sample Prepar
ation Using a Focused Ion Beam and a Probe Manipul
ator "(known example 4).

In this method, as shown in FIG. 3A, both sides of a target position on a wafer 208 are processed in a stepwise manner by FIB1 to produce a cross-sectional sample thin film 207, and then the sample stage is inclined. Thus, the angle between FIB1 and the sample surface is changed to irradiate the sample, and as shown in FIG. 3B, the periphery of the sample thin film is cut by FIB1, and the sample thin film 207 is separated from the wafer.
Then, the wafer is taken out from the FIB apparatus, the glass rod is brought close to the processing portion in the atmosphere, the sample thin film 207 is adsorbed on the glass rod by using static electricity, and is taken out from the wafer. And place it on the mesh so that it is electrostatically attracted or face the processed surface to the transparent adhesive. As described above, even if most of the outer shape of the micro sample is processed by the ion beam without removing the processed micro sample in the apparatus, the analysis can be performed by introducing the separated micro sample into the TEM.

With these techniques, it is possible to take out only a small sample or a thin sample for inspection from a sample without dividing the wafer, and return the taken-out wafer to the next process. Therefore, there is no semiconductor device lost due to the division of the wafer as in the related art, so that the manufacturing yield of the total semiconductor device can be increased and the manufacturing cost can be reduced.

[0012]

The above conventional methods have the following problems. That is, in order to form the bottom hole 8 in the above-mentioned known example 1, to form the oblique groove 408 in the known example 2, and to cut out the periphery of the sample thin film 207 in the known example 4, The attitude of the tilt angle is changed, which is performed by the sample stage. However, as the diameter of the wafer increases, the size of the sample stage also increases. It takes time to incline the large stage with high accuracy, and as a result, there is a problem that the sample preparation time becomes long. Also, because the sample stage itself is so heavy that the eccentricity is not maintained before and after tilting and the sample position moves relative to the FIB optical system, the focus of the FIB deviates relatively greatly from the sample surface, and the sample surface is observed. This causes a problem that the FIB optical system needs to be readjusted. Further, the tilt function of the sample stage causes the sample stage itself and the sample chamber containing the sample stage to be large. Recent trend is wafer diameter of 20
In the transition from 0 mm to 300 mm, an additional 400
mm, the stage will have to be enlarged,
It is inevitable to avoid the above-mentioned problem associated with the tilt of the sample stage. On the other hand, if the tilting function can be omitted from the sample stage of the device, the overall size of the device can be reduced and problems such as misalignment of the sample position caused by tilting the sample can be solved.
In the conventional method described above, a micro sample is separated or prepared for separation from the original sample (wafer), and micro area analysis, observation,
Preparation of a sample for measurement cannot be realized. In the first place, it was essential to change the attitude of the sample tilt angle, in order to separate or prepare for separation of the micro sample from the original sample.
This is because there was a stereotype that irradiation of the sample surface with ion beams at at least two different angles was indispensable. Here, the inclination of the stage means that the stage is rotated around a line segment included in the stage surface or a parallel line segment, and is hereinafter simply referred to as the inclination of the stage.

In view of the above-mentioned problems, a first object of the present invention is to break down conventional stereotypes without tilting the sample stage and obtain a desired sample from an original sample such as an electronic component such as a semiconductor wafer or a device. Separate or prepare a micro sample containing a specific area, and analyze or observe the micro area,
An object of the present invention is to provide a method for preparing a sample for measurement. A second object is to provide a sample preparation apparatus suitable for achieving the first object.

[0014]

The first aspect as described above.
Is achieved by the following.

The basic elements of the present invention for overcoming the conventional stereotype that the change of the inclination angle of the sample is indispensable are as follows: (1) The mounting surface of the sample and the ion beam on the sample An ion beam processing method is characterized in that the angle formed with the irradiation axis is fixed, and the sample is irradiated with the ion beam from a plurality of directions to separate or prepare a desired portion of the sample.

According to the ion beam processing method of this means,
An ion beam processing method for analyzing, observing, and measuring a micro area by separating or preparing a micro sample including a desired specific area from a sample of an electronic component such as a semiconductor wafer or a device without tilting the sample stage. Can be realized.

(2) The sample is irradiated with an ion beam by setting the angle between the ion beam irradiation axis on the sample and the sample surface to be more than 0 ° and at most less than 90 °. And fixing the angle between the sample and the sample surface, and separating or preparing to separate a desired portion of the sample by irradiation with an ion beam.

According to the sample preparation method of this means, a minute sample including a desired specific region is separated or prepared for separation from a sample such as an electronic component such as a semiconductor wafer or a device without tilting the sample stage. Area analysis and observation,
A sample preparation method for measurement can be realized. And (3) setting the angle between the ion beam irradiation axis on the sample and the sample surface to 30 to 75 degrees, irradiating the sample with the ion beam, and forming the angle between the ion beam irradiation axis on the sample and the sample surface. And fixing or preparing a desired portion of the sample by ion beam irradiation.

According to the sample preparation method of this means, a minute sample including a desired specific region is separated or prepared for separation from a sample such as an electronic component such as a semiconductor wafer or a device without tilting the sample stage. Area analysis and observation,
A sample preparation method for measurement can be realized. In particular, when the FIB irradiation angle is 30 to 75 degrees, observation of the sample surface is suitable, and the shape of the minute sample can be made suitable for production. (4) a focused ion beam irradiation optical system, secondary particle detection means for detecting secondary particles generated from the sample by the focused ion beam irradiation, and a sample stage on which the sample substrate is mounted. In a sample preparation method of separating or preparing to separate a micro sample from a sample using a sample preparation apparatus having at least the angle between the axis of irradiation of the focused ion beam to the sample and the surface of the sample, the angle exceeding 0 ° and at most 90 ° Irradiate the sample with a focused ion beam at less than degree, and then rotate the sample around the sample surface normal as the rotation axis, and irradiate the sample with the fixed angle between the focused ion beam irradiation axis on the sample and the sample surface The above object is also achieved by a sample preparation method characterized in that a micro sample is separated or prepared for separation.

That is, an element of the present invention for breaking down the conventional stereotype is to incorporate a rotating operation of the sample stage around the normal of the sample surface of the sample stage as a rotation axis into a sample preparation method suitable for the purpose. According to the sample preparation method of the present means, without tilting the sample stage, a minute sample including a desired specific region is separated or prepared for separation from a sample such as an electronic component such as a semiconductor wafer or a device, and a minute region analysis or A method for preparing a sample for observation and measurement can be realized.

Further, even in the case where the sample stage has a tilt function, the tilt time of the stage is not required, and the sample preparation time is relatively shortened. Further, the problem that the sample surface cannot be observed before and after the tilt of the sample stage is reduced.

(5) The method for preparing a sample according to the above (4), wherein a desired portion of the sample is supported by a probe.

According to the sample preparation method of this means, a minute sample including a desired specific region can be separated from a sample such as an electronic component such as a semiconductor wafer or a device without tilting the sample stage, and the minute region analysis and the like can be performed. A method for preparing a sample for observation and measurement can be realized. Further, by supporting the micro sample with the probe and extracting the micro sample from the sample substrate, the cross section of the micro sample can be observed in detail, and the processing position of the cross section can be controlled with high accuracy. Note that a method for supporting the micro sample may be any method that can indicate the micro sample, such as fixing with a deposition film or fixing with electrostatic force.

(6) A sample preparation method for observation, analysis or measurement, wherein the angle between the focused ion beam irradiation axis on the sample and the sample surface is greater than 0 ° and at most less than 90 °. Forming a square hole by irradiating the sample with a focused ion beam, rotating the sample around the sample surface normal as a rotation axis, and rotating the focused ion beam onto the surface of the sample substrate after the rotation. Forming a diagonal groove, forming a cantilever sample held by the support portion on the sample substrate, and bringing a desired portion of the cantilever sample into contact with a desired portion of the transfer means, and irradiating a deposition gas. A step of fixing the cantilever sample and a desired portion of the transfer means by irradiating a focused ion beam to a region including the contact portion to form a deposition film, and irradiating a focused ion beam. And cutting the support unit by a,
And a method for preparing a sample.

According to the sample preparation method of the present means, a minute sample including a desired specific region is separated or prepared for separation from a sample such as an electronic component such as a semiconductor wafer or a device without tilting the sample stage. Area analysis and observation,
A sample preparation method for measurement can be realized. Further, it becomes possible to observe the cross section of the minute sample in detail, and it is possible to control the processing position of the cross section with high accuracy.

(7) A sample preparation method for observation, analysis or measurement, wherein an angle formed between the axis of irradiation of the focused ion beam on the sample and the surface of the sample is more than 0 ° and at most less than 90 °. A step of forming a square hole by irradiating a focused ion beam to form a thin film, a step of rotating a sample around a sample surface normal line as a rotation axis, and separating the sample thin film by focused ion beam irradiation after rotation. Or a step of preparing for separation.

According to the sample preparation method of this means, a minute sample including a desired specific region is separated or prepared for separation from a sample such as an electronic component such as a semiconductor wafer or a device without tilting the sample stage. Area analysis and observation,
A sample preparation method for measurement can be realized. In addition, since a process such as an ion beam assisted deposition is not included, the time for preparing a sample can be reduced.

(8) The above (3), (4), (5),
(6) In the sample preparation method according to (7), a plurality of micro-sample preparation methods, wherein at least two or more micro-samples are separated or prepared for separation, the entire periphery of the micro-sample is ion beam-processed. A sample manufacturing method, wherein after processing to the middle of the step, and then rotating the sample, the processing around each of the minute samples is sequentially continued.

According to the sample preparation method of this means, a minute sample including a desired specific region is separated or prepared for separation from a sample such as an electronic component such as a semiconductor wafer or a device without tilting the sample stage. Area analysis and observation,
A sample preparation method for measurement can be realized. In particular, a plurality of samples can be manufactured with high throughput.

The second object is achieved by the following.

(9) A focused ion beam irradiation optical system,
And at least a sample stage on which the sample substrate is mounted,
In a focused ion beam apparatus that separates or prepares a small sample from a sample substrate, a structure in which the angle formed between the approximate center axis of a mechanical column including a focused ion beam irradiation optical system and the sample mounting surface of the sample stage is fixed. And a device for separating a desired portion of the sample, and a probe for supporting the separated sample.

According to the sample manufacturing apparatus of the present means, a minute sample including a desired specific region is separated or prepared for separation from a sample such as an electronic component such as a semiconductor wafer or a device without tilting the sample stage. Area analysis and observation,
A sample manufacturing apparatus for manufacturing a sample for measurement can be realized. Further, by supporting the micro sample with the probe and extracting the micro sample from the sample substrate, the cross section of the micro sample can be observed in detail, and a sample manufacturing apparatus capable of controlling the cross section processing position with high accuracy can be realized. Note that a method for supporting the micro sample may be any method that can indicate the micro sample, such as fixing with a deposition film or fixing with electrostatic force.

(10) An optical system for irradiating a focused ion beam, secondary particle detecting means for detecting secondary particles generated from a sample by the irradiation of the focused ion beam, and a sample stage on which a sample substrate is mounted are provided at least. In a sample preparation apparatus for separating or preparing a minute sample from a sample substrate, an angle between a focused ion beam irradiation axis on the sample and the sample surface is greater than 0 ° and less than 90 ° at most. The stage has a function of rotating the specimen surface normal as a rotation axis, and the irradiation position of the focused ion beam for separating or preparing the sample after the rotation is rotated by the focused ion beam irradiation or the separately provided electron beam irradiation system. Function to determine by using image display means to display the secondary particle image formed by secondary particles generated from the sample by the electron beam And sample manufacturing apparatus characterized by having.

According to the sample preparation apparatus of this means, a minute sample including a desired specific region is separated or prepared for separation from a sample such as an electronic component such as a semiconductor wafer or a device without tilting the sample stage. Area analysis and observation,
Automated operation of the device for preparing samples for measurement,
It is suitable from the viewpoint that the burden on the operator can be reduced, and it is possible to realize a sample manufacturing apparatus that can reduce the sample surface damage and can manufacture a sample in a short time.

(11) At least an optical system for irradiating the focused ion beam, secondary particle detecting means for detecting secondary particles generated from the sample by the irradiation of the focused ion beam, and a sample stage on which a sample substrate is mounted are provided. In a sample preparation apparatus that separates or prepares a micro sample from a sample substrate, an angle between a focused ion beam irradiation axis on the sample and the sample surface is greater than 0 ° and at most less than 90 °,
The sample stage has a function of rotating around the sample surface normal as a rotation axis, and the irradiation position of the focused ion beam for separating or preparing the sample after the rotation is adjusted by the focused ion beam or an electron beam from a separately provided electron beam irradiation system. A sample manufacturing apparatus is characterized by having a function of determining a secondary particle image formed by secondary particles generated from a sample by irradiation with a beam by using image processing results.

According to the sample preparation apparatus of this means, a minute sample including a desired specific region is separated or prepared for separation from a sample such as an electronic component such as a semiconductor wafer or a device without tilting the sample stage. Area analysis and observation,
Automated operation of the device for preparing samples for measurement,
It is suitable from the viewpoint that the burden on the operator can be reduced, and it is possible to realize a sample manufacturing apparatus that can reduce the sample surface damage and can manufacture a sample in a short time.

(12) At least a focused ion beam irradiation optical system, a secondary particle detecting means for detecting secondary particles generated from a sample by the focused ion beam irradiation, and a sample stage on which a sample substrate is placed In a sample preparation apparatus for separating or preparing to separate a micro sample from a sample substrate, an angle between an axis of irradiation of the focused ion beam on the sample and the sample surface is in a range of 30 to 75 degrees, and the sample stage is provided on the sample surface. Transfer means for transferring the extracted micro sample obtained by separating the desired portion of the sample substrate to another member, having a function of rotating the normal line as a rotation axis, and holding means for holding a sample holder for mounting the micro extracted sample And a sample preparation apparatus characterized by having the following.

According to the sample preparation apparatus of the present means, a small sample including a desired specific region is separated or prepared for separation from a sample such as an electronic component such as a semiconductor wafer or a device without tilting the sample stage. Area analysis and observation,
It is suitable for preparing samples for measurement, especially when the FIB irradiation angle is 30 to 75 degrees, so that the observation of the sample surface is suitable and the micro sample shape can be made into a shape suitable for manufacturing. it can. It is possible to realize a sample manufacturing apparatus that can manufacture a sample in a shorter time.

(13) At least a focused ion beam irradiation optical system, a secondary particle detecting means for detecting secondary particles generated from a sample by the focused ion beam irradiation, and a sample stage on which a sample substrate is mounted are provided. In a sample preparation apparatus for separating or preparing to separate a micro sample from a sample substrate, an angle formed between a focused ion beam irradiation axis on the sample and the sample surface is 45 degrees, and the sample stage rotates the sample surface normal with respect to the rotation axis. Having a function of rotating, a transfer means for transferring the extracted micro sample separated from the desired portion of the sample substrate to another member, and a sample holder holding means for mounting the micro extracted sample. It is a sample preparation device that is a feature.

According to the sample preparation apparatus of the present means, a minute sample including a desired specific region is separated or prepared for separation from a sample such as an electronic component such as a semiconductor wafer or a device without tilting the sample stage. Area analysis and observation,
Preparation of the sample for measurement, both the sample surface and the sample cross section,
When observing by FIB irradiation, the FIB irradiation angle is
It can be set to 45 degrees, both can be performed under similar conditions, and it is suitable for separating or preparing for sample separation.
Further, it is possible to realize a sample preparation apparatus which has less damage to the sample surface and can prepare a sample in a short time.

(14) The above (10), (11), (1)
2) and (13), the focused ion beam irradiation axis on the sample substantially coincides with the mechanical center axis of the substantially centrally symmetric objective lens which is a component of the focused ion beam irradiation optical system. And a sample preparation apparatus characterized by the above.

According to the sample preparation apparatus of this means, a minute sample including a desired specific region is separated or separated from a sample such as an electronic component such as a semiconductor wafer or a device without tilting the sample stage. Area analysis and observation,
In order to realize a sample preparation device that can prepare a sample for measurement, it is necessary to mechanically define the angle between the sample stage surface and the approximately centrally symmetric objective lens, which is a component of the focused ion beam irradiation optical system. Since it can be realized, the device design can be simplified.

(15) A focused ion beam irradiation optical system, a secondary particle detecting means for detecting secondary particles generated from a sample by the focused ion beam irradiation, and a sample stage on which a sample substrate is mounted. In order to separate or prepare the micro sample from the sample substrate at least, the sample substrate is irradiated with a focused ion beam around the micro sample from a plurality of incident directions to separate or separate the micro sample. The sample preparation apparatus to be prepared is characterized in that the focused ion beam irradiation optical system has a focused ion beam tilting function capable of changing a focused ion beam irradiation axis to the sample by at least 15 degrees.

According to the sample preparation apparatus of this means, a minute sample including a desired specific region is separated or prepared for separation from a sample such as an electronic component such as a semiconductor wafer or a device without tilting the sample stage. Area analysis and observation,
A sample preparation apparatus capable of preparing a sample for measurement can change the incident direction of the focused ion beam by at least 15 degrees,
This is realized by the focused ion beam tilt function. In particular, since a focused ion beam incident angle can be selected in sample preparation, various sample preparation methods and sample shapes can be realized.

(16) In the sample preparation apparatus according to the above (15), the focused ion beam irradiation function on the sample can be changed by at least 15 degrees, and the focused ion beam tilting function includes a focused ion beam irradiation optical system. A sample preparation apparatus characterized by being realized by a tilt angle variable mechanism for the sample stage.

According to the sample preparation apparatus of this means, a minute sample including a desired specific region is separated or prepared for separation from a sample such as an electronic component such as a semiconductor wafer or a device without tilting the sample stage. Area analysis and observation,
A sample preparation apparatus capable of preparing a sample for measurement is realized by a tilt angle variable mechanism with respect to a sample stage of a mechanical column including a focused ion beam irradiation system. In particular, since a focused ion beam incident angle can be selected in sample preparation, various sample preparation methods and sample shapes can be realized.

(17) In the sample preparation apparatus according to the above (15), a focused ion beam tilting function of changing a focused ion beam irradiation axis to the sample by at least 15 degrees is realized by an electric deflection mechanism. And a sample preparation apparatus.

According to the sample preparation apparatus of this means, a minute sample including a desired specific region is separated or prepared for separation from a sample such as an electronic component such as a semiconductor wafer or a device without tilting the sample stage. Area analysis and observation,
A sample manufacturing apparatus capable of manufacturing a sample for measurement is realized by an electric deflection mechanism. In particular, the mechanical device configuration is simplified, the manufacturing cost can be reduced, and the focused ion beam incident angle can be selected in the sample preparation, so that various sample preparation methods and sample shapes can be realized.

(18) The above (10), (11), (1)
2), (13), (14), (15), (16), and (17), wherein the sample stage is configured such that a line segment or a parallel line segment included in the stage plane is inclined with respect to the tilt axis. A sample preparation apparatus having a structure in which the inclination angle is fixed. And

According to the sample preparation apparatus of this means, since the sample stage does not have a tilting function, the size of the entire apparatus can be reduced, and a desired specific region can be formed from a sample such as an electronic component such as a semiconductor wafer or a device. A sample preparation apparatus capable of separating or preparing to separate microsamples and preparing samples for microregion analysis, observation, and measurement can be realized.

(19) The above (9), (10), (1)
1), (12), (13), (14), (15), (1
6) and the sample preparation apparatus according to (17), wherein the sample stage is constituted by a combination of a stage rotating at a specific fixed angle and a stage rotatable at an arbitrary angle. A manufacturing device.

According to the sample preparation apparatus of this means, since the sample stage does not have a tilting function, the entire apparatus can be reduced in size, and a desired specific region can be formed from a sample such as an electronic component such as a semiconductor wafer or a device. A sample preparation apparatus capable of separating or preparing to separate microsamples and preparing samples for microregion analysis, observation, and measurement can be realized. In particular,
This is suitable for saving the time required for alignment and increasing the throughput of sample preparation.

(20) The above (9), (10), (1)
1), (12), (13), (14), (15), (1
6) and the sample preparation apparatus according to (17),
A sample preparation apparatus characterized in that the sample stage is constituted by a combination of a stage rotating at at least one of a fixed angle of 90 degrees and 180 degrees and a stage rotatable at an arbitrary angle.

According to the sample preparation apparatus of this means, since the sample stage has no tilting function, the size of the entire apparatus can be reduced, and a desired specific region can be formed from a sample such as an electronic component such as a semiconductor wafer or a device. A sample preparation apparatus capable of separating or preparing to separate microsamples and preparing samples for microregion analysis, observation, and measurement can be realized. In particular,
This is suitable for saving the time required for alignment and increasing the throughput of sample preparation.

[0055]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a sample preparation apparatus according to the present invention is characterized in that an angle between a sample surface on a stage and a focused ion beam irradiation axis is greater than 0 ° and less than 90 ° at most. A focused ion beam irradiation optical system arranged so as to irradiate a beam, secondary particle detection means for detecting secondary particles generated from the sample by the irradiation of the focused ion beam, and a sample stage having no tilt mechanism. And at least one of them.

Hereinafter, specific examples of the embodiment will be described.

<Embodiment 1> A schematic configuration diagram of a sample preparation apparatus according to an embodiment of the present invention will be described with reference to FIG.

The sample preparation apparatus 17 has a vacuum vessel 41 in which an FIB comprising an ion source 32, a beam limiting aperture 33, an ion beam scanning electrode 34, an ion beam lens 31, and the like is provided. Irradiation optical system 3
5. Secondary particle detector 36 for detecting secondary electrons and secondary ions emitted from the sample by FIB irradiation, a deposition gas source 37 for supplying a source gas for forming a deposition film in an ion beam irradiation region, a manipulator 42, a probe 3 attached to the tip, a sample stage 39 on which a sample substrate 38 such as a semiconductor wafer or a semiconductor chip is mounted, and a sample holder 40 for fixing a small extracted sample obtained by extracting a part of the sample substrate.
And so on. Here, the FIB irradiation optical system 35
Is set with respect to the stage 39 so that the angle between the approximate center axis of the objective lens 44 and the sample surface is 45 degrees. Further, the sample stage has a function of rotating a vertical line segment with respect to the sample surface as a rotation axis. Further, as a device for controlling this device, a stage control device 61 mainly composed of an electric circuit and an arithmetic device, a manipulator control device 6
2. An amplifier 63 of the secondary electron detector, a deposit gas source control device 64, a FIB control device 65, and a calculation processing device 74 are arranged. The calculation processing device 74 has a function of recognizing a sample shape by performing image processing on a secondary electron image formed by secondary electrons generated from the sample by the irradiation of the FIB. Further, it has a function of irradiating the FIB 1 to a desired position of the sample shape by the FIB control device 65 based on the sample shape information.

Next, the operation of the sample preparation apparatus will be described. First, the sample substrate 38 is irradiated with ions emitted from the ion source 32 through the beam limiting aperture 33, the ion beam lens 31, and the objective lens 44. The FIB 1 is narrowed to a diameter of several nanometers to about 1 micrometer on a sample. When the FIB 1 is irradiated on the sample substrate 38, constituent atoms on the sample surface are released into a vacuum by a sputtering phenomenon. Therefore, by scanning the FIB 1 using the ion beam scanning electrode 34, processing on a micrometer to sub-micrometer level can be performed.
Also, while introducing the deposition gas into the sample chamber, the FIB
By irradiating 1 to the sample substrate 38, a deposition film can be formed. As described above, the sample substrate 38 can be processed by skillfully using the sputtering or the deposition by the FIB 1. The deposition film formed by the irradiation of the FIB 1 is used for connecting the sample to the contact portion at the tip of the probe 3 and for fixing the extracted sample to the sample holder 40. In addition, the FIB 1 is scanned, secondary electrons and secondary ions emitted from the sample are detected by the secondary particle detector 36, and the intensity is converted into the brightness of the image, so that the sample substrate 38, the probe 3, etc. Can be observed.

Next, a sample manufacturing method according to an embodiment of the present invention will be described with reference to FIG. Here, for the sake of understanding of FIG. 1, as a supplement, FIG. 8 shows a square hole 501 (a) in which the FIB irradiation axis is made normal to the sample surface, and the FIB irradiation axis is at 45 degrees with respect to the sample surface. The created square hole 502 (b) is shown for reference. For sample preparation, first, TE
A mark indicating the position of a thin film for M observation and a protective film are formed. Next, the FIB 1 is scanned on the sample substrate into a rectangle whose one side is the direction in which the irradiation axis of the FIB with respect to the substrate surface is projected onto the sample surface, and two square holes 101 (about 15 μm in depth inclined at a depth in the depth direction). As in FIG. A), a notch groove 102 (FIG. B) similarly inclined in the depth direction is formed. The FIB irradiation axis is at 45 degrees to the sample surface. Next, the sample is rotated about 180 degrees with the axis perpendicular to the sample surface as the rotation axis. Here, image processing is performed on a secondary electron image formed by secondary electrons generated from the sample by irradiation of the FIB 1, thereby recognizing the two square holes and the notch grooves formed so far. Then, the FIB control unit 65 controls the FIB irradiation position based on the sample shape information, and similarly forms a groove 103 inclined in the depth direction (FIG. C). Next, the tip of the probe 3 is brought into contact with the microsample 6 on the substrate by driving the probe control device. Next, a deposition gas is supplied from a gas nozzle, FIB 1 is locally irradiated to a region including the tip of the probe 3, a deposition film 105 is formed, and the separated portion of the substrate in contact with the probe 3 is connected. (Figure
d). By cutting off the support portion 104 with the FIB 1, the micro sample 6 is supported by the connected probe 3 (FIG. E). The microsample 6 can be extracted by moving the probe 3 upward (FIG. F). Subsequent steps are the same as the conventional one. That is, the sample stage is operated while the probe is stopped above the sample surface, and the micro sample is moved to the sample mesh. The micro sample is
Fix to sample mesh with depot membrane. Cut the probe with FIB and separate from the micro sample. Finally, the observation area in this micro sample is thinned with FIB to a thickness of about 100 nm,
The TEM sample is completed.

In this method, the sample is rotated by about 180 degrees to form a groove inclined in the depth direction in FIG. 3C, but the vertical axis with respect to the sample surface is used as the rotation axis. It may be formed by rotating 90 degrees. The micro sample shape in this case is as shown in FIG. 5A, and in the above example in which the sample is rotated by about 180 degrees, as shown in FIG. 5B. In addition, two square holes (Fig. A), a notch groove similarly inclined in the depth direction (Fig. B), and approximately 180
There is no particular limitation on the order of forming the grooves (FIG. C) formed by rotating by about or 90 degrees.

In this embodiment, the secondary electron image formed by the secondary electrons generated from the sample by the irradiation of the FIB is image-processed, so that the two square holes and the notch grooves formed so far are formed. Then, the FIB controller controlled the FIB irradiation position based on the sample shape information. This makes it possible to automate the operation and reduce the burden on the operator. However, it is not always necessary to use the image processing device, and the device operator may observe the secondary electron image on the image display device and control the FIB irradiation position.

When a plurality of micro samples are prepared, it is possible to prepare each sample according to the order. First, a sample having a depth of about 15 μm inclined in the depth direction is used.
One square hole 101 (FIG. A) and a notch groove 102 (FIG. B) similarly inclined in the depth direction are first formed in necessary places for a plurality of samples. Next, the sample is rotated about 180 degrees with the axis perpendicular to the sample surface as the rotation axis. next,
Subsequent to the alignment of each sample, a groove 103 inclined in the depth direction is formed for each sample (FIG. C). Next, the probe control device is driven, and a plurality of microsamples 6 are manufactured using the probe 3 in the order of the TEM samples. In this manner, since a relatively time-consuming rotation operation can be reduced, a plurality of samples can be manufactured with higher throughput than when each sample is manufactured in order.

In the embodiment described above, the angle between the FIB and the sample surface is not changed at 45 degrees in a series of steps for separating the micro sample from the sample substrate. That is,
It does not include the step of tilting the stage. Therefore, according to the present embodiment, even if the tilting function of the sample stage is omitted in order to reduce the size of the entire apparatus, a micro sample is separated or prepared for separation, and a sample for micro area analysis, observation, and measurement is prepared. Production becomes possible. Also, unlike the present embodiment,
The present invention is effective even in a case where the sample stage has a tilting function, the tilting time of the stage is not required, and the sample preparation time is relatively shortened. Further, the problem that the sample surface cannot be observed before and after the tilt of the sample stage is reduced. Further, in this embodiment, since the micro sample is extracted from the sample substrate during the processing of the TEM sample thin film, the micro sample cross section can be observed in detail, and the cross section processing position can be controlled with high accuracy.

Further, according to the present embodiment, it is possible to separate or prepare a minute sample from the sample and to prepare a sample for minute area analysis, observation, and measurement, thereby automating the operation of the apparatus and reducing the burden on the operator. In view of the above, a sample preparation apparatus suitable for the present invention is provided.

In this embodiment, the sample stage is
It consists of a stage that rotates at a specific fixed angle and a stage that can rotate at an arbitrary angle. The stage that rotates at a fixed angle is operated by the above-described 180-degree rotation or 90-degree rotation. The stage that rotates at an arbitrary angle is operated by adjusting the processing position on the sample. Generally, the accuracy of determining the rotation angle of an arbitrary angle rotation stage is at most 0.01 degree. As in the present embodiment, when minute alignment is required after rotation, accuracy is insufficient. However, in a stage having only a function of rotating at a specific fixed angle, it is possible to further increase the rotation accuracy. Therefore, in this embodiment, it is rotated by 180 degrees or 9
Operating the stage that rotates at a fixed angle to adjust the processing position after rotation by 0 degrees is suitable for saving the time required for alignment and increasing the throughput of sample preparation.

In the present embodiment, the FIB irradiation axis is set to 45 degrees with respect to the sample surface. However, when the FIB irradiation axis is set to 45 degrees, both the sample surface and the sample cross section are observed when FIB irradiation is performed. In each case, the FIB irradiation angle is 45 degrees, and both can be performed under the same conditions. Therefore, it is suitable for separating or preparing to separate a sample. However, the present invention is not necessarily limited to 45 degrees, and the effect of the present invention can be obtained if the angle is less than 90 degrees. However, the FIB irradiation axis is
If it is less than 0 degrees, the processing area for separating the micro sample is enlarged, and the sample surface is wasted. In addition, when the angle exceeds 75 degrees, the actual angle to the surface of the machined wall becomes close to 90 degrees, increasing the machining depth for separating minute samples, increasing the machining time, and making it impossible to separate minute samples. May be. Therefore, in order to separate a small sample, the angle between the sample irradiation axis of the beam and the sample surface is
A range from 30 degrees to 75 degrees is preferred.

In the present embodiment, the mechanical center axis of the objective lens of the focused ion beam irradiation system is set at 45 ° with respect to the sample substrate surface so that the FIB irradiation axis is at 45 degrees to the sample surface. Although the angle is set at an angle, the device design is simplified.However, even if the angle is set to other than 45 degrees, the FIB irradiation axis can be set at 45 degrees to the sample surface by ion beam deflection. .

In the above embodiment, a semiconductor wafer having a planar shape is taken as an example of a sample. However, the present invention is not limited to a planar sample but may be applied to a sample of an arbitrary shape. In the above description, the angle between the sample surface and the irradiation axis of the ion beam sample is described. However, in the case of a sample having an arbitrary shape, the sample may be manufactured by fixing the angle with the sample mounting surface of the sample stage. For example, the present invention is also applicable to so-called micromachining, in which a minute component is separated from a sample by the present invention and connected to another minute component to produce a certain minute mechanical structure or a minute device.

In other words, the sample preparation apparatus suitable for carrying out the present example has a fixed angle formed between the approximate center axis of the mechanical column including the focused ion beam irradiation optical system and the sample mounting surface of the sample stage. What is necessary is just to make the sample preparation apparatus characterized by having a means for separating a desired portion of the sample and a probe for supporting the separated sample.
In the case of a semiconductor wafer having a flat shape as a sample, the sample mounting surface and the sample surface are parallel surfaces, and the angle between the sample irradiation axis of the focused ion beam and the sample surface, and the sample irradiation axis of the focused ion beam It is needless to say that the angle between the sample stage and the mounting surface of the sample on the sample stage is synonymous.

In this embodiment, the focused ion beam is scanned on the sample. At this time, the angle of incidence of the focused ion beam on the sample slightly changes depending on the scanning position. The change in the angle of incidence of the ion beam due to such scanning depends on the sample irradiation axis of the focused ion beam and the sample surface. Is not included in the angle change. That is, even if the focused ion beam is scanned on the sample, the angle between the sample irradiation axis of the focused ion beam and the sample surface can be fixed. In addition, the sample irradiation axis of the focused ion beam refers to the center line of the ion beam when scanning is stopped and the ion beam is incident on the sample surface when there is no deflection by the scanning electrode.

<Embodiment 2> Next, another sample manufacturing method according to an embodiment of the present invention will be described with reference to FIG. The sample preparation device is the same as the device shown in FIG.

First, a mark indicating a position for forming a thin film for TEM observation and a protective film are formed on a sample substrate. The FIB 1 is scanned on the sample substrate into a rectangle whose side is the direction in which the irradiation axis of the FIB 1 with respect to the substrate surface is projected on the sample surface, and two square holes 301 having a depth of about 15 μm and inclined in the depth direction (FIG. A) To form Here, the target sample is a thin film between two square holes,
Its thickness is about 100 nm. Next, both ends 302 of the thin film portion are cut out. Next, the sample is rotated about 90 degrees with the vertical axis relative to the sample surface as the rotation axis. Where FIB1
By performing image processing on the secondary electron image formed by the secondary electrons generated from the sample by the irradiation, the two notch grooves 301 formed so far are recognized. Then, the FIB controller 65 uses the sample shape information to
The irradiation position is controlled, the bottom of the sample thin film is cut off by the FIB 1 as shown in FIG. C, and the sample thin film 303 is separated from the sample substrate. Alternatively, the processing is terminated without leaving an indicating portion that can be broken by a slight impact, in preparation for separation in a later step, even if it does not reach separation. After that, the sample substrate is taken out of the sample preparation apparatus, and the sample thin film 303 is moved from the sample substrate to the TEM sample holder using the static electricity of the glass rod 304 in the atmosphere. Here, when the sample thin film 303, which is a micro sample, is not completely separated, the glass rod 3
The sample thin film 303 is separated from the sample substrate by applying an impact to the minute sample indicating portion by 04, and then the sample thin film 303 is moved from the sample substrate to the TEM sample holder using the static electricity of the glass rod 304 in the same manner. As described above, the present invention also includes a sample manufacturing method and a sample manufacturing apparatus in which most of the external shape of a micro sample is processed by an ion beam without removing the sample thin film 303 as a micro sample in the apparatus.

In this method (FIG. B), at least one of the two sides of the sample slice is cut before the sample is rotated by about 90 degrees, but may be cut after the sample is rotated. The order of forming the two square holes, cutting both sides of the sample slice, cutting the bottom of the sample slice, and the like is not particularly limited.

Although the image processing is used in the present embodiment, the apparatus operator may control the FIB irradiation position by observing the secondary electron image as in the first embodiment. It is.

In the embodiment described above, the angle between the FIB and the sample surface is not changed at 45 degrees in a series of steps for separating or preparing the sample from the sample substrate.
That is, the step of tilting the stage is not included. Therefore, according to the present embodiment, even if the tilting function of the sample stage is omitted in order to reduce the size of the entire apparatus, a micro sample is separated or prepared for separation, and a sample for micro area analysis, observation, and measurement is prepared. Production becomes possible. Further, unlike the present embodiment, even in the case of an apparatus in which the sample stage has a tilting function, the stage is not required to be tilted, and the sample preparation time is relatively shortened. Further, the problem that the sample surface cannot be observed before and after the tilt of the sample stage is reduced. Further, in the present embodiment, since a minute sample exists in the sample substrate at the time of processing the thin film for the TEM sample,
Although the accuracy of the cross-section processing position is relatively low compared to,
Since a process such as an ion beam assisted deposition is not included for the operation of the probe or the bonding between the probe and the micro sample, the sample preparation time can be shortened.

Note that, similarly to Embodiment 1, the FIB irradiation angle is not necessarily limited to 45 degrees, and the effect of the present invention can be obtained if the angle is less than 90 degrees.

<Embodiment 3> Next, FIG. 7 shows a schematic configuration diagram of a sample manufacturing apparatus provided with an electron beam irradiation apparatus according to an embodiment of the present invention. The sample preparation apparatus 17 has a vacuum container 41. In the vacuum container, a FIB irradiation optical system 35, a secondary particle detector 36, a deposition gas source 37, a probe 3, a sample stage 39, etc. This is the same as the sample manufacturing apparatus of the second embodiment. Similarly, the FIB irradiation optical system 35 is installed with respect to the stage 39 so that the FIB irradiation axis is at 45 degrees with respect to the sample surface. Further, the sample stage has a function of rotating a vertical line segment with respect to the sample surface as a rotation axis. In this apparatus, a field emission type electron gun 81 for emitting an electron beam, an electron beam lens 8
2. An electron beam irradiation system including an electron beam scanning electrode 83 and the like is provided. In addition to the stage control device 61, the manipulator control device 62, the amplifier 63 of the secondary electron detector, the deposit gas source control device 64, the FIB control device 65, the electron gun control device 9
1, an electron optical system control device 92, an electron beam scanning control device 93, a calculation processing device 74, and the like. Further, the calculation processing device 74 has a function of recognizing the shape of the sample by performing image processing on a secondary electron image formed by secondary electrons generated from the sample by the irradiation of the FIB or the electron beam 84. The FIB control device 65 has a function of irradiating the FIB to a desired position of the sample shape with the sample shape information, and the electron beam control device 91 has a function of irradiating an electron beam 84 to a desired position of the sample shape.

The operation of the FIB irradiation optical system 35 is described in the second embodiment.
Is the same as Next, the electron beam irradiation operation will be described. The electron source of the electron beam irradiation device is a field emission type electron gun 81.
Thus, it is possible to aim at an arbitrary position of the substrate sample 38 by the electron beam scanning electrode 84. In addition, it becomes possible to scan and irradiate the processing area 42 irradiated with the FIB. To do this, prepare the following in advance.
The FIB 1 is focused into a spot and irradiated onto the sample. Next, the spot-shaped irradiation mark is scanned with the electron beam 84, secondary electrons are detected, and the spot-shaped irradiation mark is observed to clarify the relationship between the FIB1 irradiation position and the electron beam irradiation position. It is stored in the calculation processing device 74 in advance. Therefore, from the stored information, the processing position can be observed by automatically irradiating the FIB1 processing position with an electron beam. that's all,
These controls are integrally performed by the calculation processing device 74.

The sample preparation method is the same as the method described in the first and second embodiments. However, in the first and second embodiments, the FIB is used.
Although the image processing of the secondary electron image formed by the secondary electrons generated from the sample by the FIB irradiation was used for the irradiation position control of the FIB, in this device, the secondary electron formed by the secondary electrons generated from the sample by the electron beam irradiation was used. An electronic image can be used. Using sample observation by electron beam irradiation,
Compared to sample preparation by FIB irradiation alone, sample surface damage is far less and sample preparation can be performed in a shorter time.

Further, according to the present embodiment, similarly to Embodiments 1 and 2, a micro sample is separated or prepared for separation from a sample, and a sample for micro area analysis, observation, and measurement is prepared. Needless to say, a suitable sample preparation apparatus is provided from the viewpoint that the preparation can be automated in the operation of the apparatus and the burden on the operator can be reduced.

<Embodiment 4> A schematic configuration diagram of a sample manufacturing apparatus according to an embodiment of the present invention will be described with reference to FIG.

In the present embodiment, the focused ion beam tilt function of changing the incident direction of the focused ion beam by at least 15 degrees is realized by a tilt angle varying mechanism with respect to the sample stage of the mechanical column including the focused ion beam irradiation system.

The sample preparation apparatus 17 has a vacuum vessel 41 in which a FIB comprising an ion source 32, a beam limiting aperture 33, an ion beam scanning electrode 34, an ion beam lens 31, and the like is provided. Irradiation optical system 3
5. Secondary particle detector 36 for detecting secondary electrons and secondary ions emitted from the sample by FIB irradiation, a deposition gas source 37 for supplying a source gas for forming a deposition film in an ion beam irradiation region, a manipulator 42, a probe 3 attached to the tip, a sample stage 39 on which a sample substrate 38 such as a semiconductor wafer or a semiconductor chip is mounted, and a sample holder 40 for fixing a small extracted sample obtained by extracting a part of the sample substrate.
And so on. Here, the FIB irradiation optical system 35
Is configured such that the angle of the FIB irradiation axis with respect to the sample substrate surface can be set from 75 degrees to 90 degrees. In this embodiment, the FIB irradiation optical system 35 and the vacuum vessel 41 are connected by a bellows 45 to utilize the deformation of the bellows. FIG.
10A shows a state in which the angle of the FIB irradiation axis with respect to the sample substrate surface is 90 degrees, and FIG. 10B shows a state in which the angle is 75 degrees. Further, as a device for controlling this device, a stage control device 61 mainly composed of an electric circuit and an arithmetic device, a manipulator control device 6
2. An amplifier 63 of the secondary electron detector, a deposit gas source control device 64, a FIB control device 65, and a calculation processing device 74 are arranged.

Next, a method for fabricating a sample according to this embodiment is shown in FIG. That is, conventionally, by tilting the sample stage, F
The oblique groove 408 was formed by irradiating the sample surface with IB1 obliquely, but instead of tilting the sample stage,
The ion beam irradiation system 35 may be inclined as shown in FIG. 10 (b), and an oblique groove 408 may be formed as shown in FIG. 11 (c). Other steps are the same as those in the related art.

According to the sample preparation apparatus of this means, a minute sample including a desired specific region is separated or prepared for separation from a sample such as an electronic component such as a semiconductor wafer or a device without tilting the sample stage. Area analysis and observation,
A sample preparation apparatus capable of preparing a sample for measurement can change the incident direction of the focused ion beam by at least 15 degrees,
This is realized by the focused ion beam tilt function. In particular, in the present embodiment, since a focused ion beam incident angle can be selected in sample preparation, various sample preparation methods and sample shapes can be realized.

<Embodiment 5> A schematic configuration diagram of a sample manufacturing apparatus according to an embodiment of the present invention will be described with reference to FIG.

In the present embodiment, the focused ion beam tilt function of changing the incident direction of the focused ion beam by at least 15 degrees is realized by electrical deflection.

The sample preparation apparatus 17 has a vacuum container 41 in which a FIB irradiation optical system 35, a secondary particle detector 36, a deposition gas source 37, a probe 3, a sample stage 39, and a sample holder 40 are provided. This is the same as in the third embodiment. Here, an angle changing electrode 51 is further provided between the objective lens 44 and the sample stage 39. Then, the FIB irradiation axis can be set by changing the angle of the FIB irradiation axis with respect to the sample substrate surface from 75 degrees to 90 degrees by the ion beam deflecting action of the present electrode. Further, as devices for controlling the present device, a stage control device 61 mainly composed of an electric circuit and an arithmetic device, a manipulator control device 62, an amplifier 63 of a secondary electron detector, a deposition gas source control device 64, a FIB control device 65, and a calculation device A processing device 74 and the like are arranged.

Next, a method for fabricating a sample according to this embodiment is shown in FIG. That is, conventionally, by tilting the sample stage, F
The oblique groove 408 was formed by irradiating the sample surface with IB1 obliquely, but instead of tilting the sample stage,
The ion beam irradiation axis is tilted with respect to the sample by the angle changing electrode 51 as shown in FIG.
The oblique groove 408 may be formed as shown in FIG. Other steps are the same as those in the related art.

According to the sample preparation apparatus of this means, a small sample including a desired specific region is separated or separated from a sample such as an electronic component such as a semiconductor wafer or a device without tilting the sample stage. Area analysis and observation,
A sample preparation apparatus capable of preparing a sample for measurement can change the incident direction of the focused ion beam by at least 15 degrees,
This is realized by the electric deflection effect of the angle changing electrode. In particular, the mechanical device configuration is simplified, the device manufacturing cost can be reduced, and the focused ion beam incident angle can be selected in the sample preparation, so that various sample preparation methods and sample shapes can be realized.

[0092]

In the sample manufacturing method according to the present invention, the angle between the FIB and the sample surface is not changed in the series of steps for separating the micro sample from the sample substrate, and the step of tilting the stage is not included. Therefore, in the sample manufacturing method according to the present application, even if the tilting function of the sample stage is omitted to separate the sample, the sample for separation or preparation for minute area analysis, observation, and measurement is prepared even if the tilt function of the sample stage is omitted. Production becomes possible. In addition, even when the sample stage is an apparatus having a tilting function, the stage does not need to be tilted, and the sample preparation time is relatively shortened. Further, the problem that the sample surface cannot be observed before and after the tilt of the sample stage is reduced.

According to the sample preparation apparatus of the present invention,
Provided is a sample preparation apparatus suitable for separating or preparing a micro sample from a sample and preparing a sample for micro area analysis, observation, and measurement from the viewpoint that the operation of the apparatus can be automated and the burden on the operator can be reduced. You.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining an embodiment of a sample manufacturing method according to the present invention.

FIG. 2 is a view for explaining an example of a conventional method for producing a TEM sample, particularly using an FIB and a transporting means.

FIG. 3 is a view for explaining an example of a conventional method of manufacturing a TEM sample, in particular, an example of processing a thin film using a FIB in a sample substrate.

FIG. 4 is a configuration block diagram showing an embodiment of a sample preparation apparatus according to the present invention.

FIG. 5 is a diagram of a micro sample manufactured by the sample manufacturing method according to the present invention.

FIG. 6 is a view for explaining an embodiment of a sample manufacturing method according to the present invention.

FIG. 7 is a configuration block diagram showing one embodiment of a sample preparation apparatus according to the present invention.

FIG. 8 is a supplementary diagram for understanding FIG. 1;

FIG. 9 is a diagram for explaining an example of a conventional method for producing a TEM sample, particularly using an FIB and a transport means.

FIG. 10 is a configuration block diagram showing one embodiment of a sample preparation apparatus according to the present invention.

FIG. 11 is a configuration block diagram showing an embodiment of a sample preparation apparatus according to the present invention.

FIG. 12 is a view for explaining a procedure of manufacturing a sample according to the embodiment.

[Explanation of symbols]

1. FIB, 2. sample, 3. probe, 4. depot source, 5.
Deposited gas, 6 micro sample, 7 square hole, 8 bottom hole, 9 notch groove, 10 gas nozzle, 31 ion beam lens, 32 liquid metal ion source, 33 beam limiting aperture, 34 ion beam Scanning electrode, 35 ...
FIB irradiation optical system, 38: secondary particle detector, 37: deposit source, 38: sample substrate, 39: sample stage, 40: sample holder, 41: vacuum vessel, 42: manipulator, 44
... Objective lens, 45 ... Bellows, 51 ... Angle changing deflection electrode, 61 ... Stage control device, 62 ... Manipulator control device, 63 ... Amplifier, 64 ... Depot gas source control device
65: FIB control device, 74: calculation processing device, 76: sample holder, 77: holder cassette, 78: transfer means, 80
... Stage control device, 81 ... Field emission type electron gun, 82 ...
Electron beam lens, 83 ... Electron beam scanning electrode, 84 ...
Electron beam, 91: electron gun controller, 92: electron beam optical system controller, 93: electron beam scanning controller, 10
1 ... square hole, 102 ... notch groove, 103 ... notch groove,
104: Supporting part, 105: Deposition film, 207: Sample thin film, 208: Thin film, 209: TEM sample holder. 3
01 ... square hole, 302 ... both ends of thin film, 303 ... sample thin film, 3
04 ... Glass rod. 501: square hole, 502: square hole.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hidemi Koike 882 Ma, Hitachinaka-shi, Ibaraki Pref. Within the Measuring Instruments Group, Hitachi, Ltd. Inside the Central Research Laboratory (72) Inventor Eiichi Seya 1-280 Higashi Koigakubo, Kokubunji-shi, Tokyo Inside the Central Research Laboratory Hitachi, Ltd. (72) Mitsuo Tokuda 882 Ma, Hitachinaka City, Ibaraki Pref. Within the group (72) Inventor Satoshi Tomimatsu 1-280 Higashi Koikekubo, Kokubunji-shi, Tokyo Inside the Central Research Laboratory, Hitachi, Ltd. (Reference) 2G052 AA13 EC14 EC18 GA34 5C001 AA01 AA 06 CC07 5C034 AB01 AB04

Claims (10)

[Claims] 1. A step of mounting a sample on a sample stage, and a first processing step of processing the sample by irradiating the sample with an ion beam while tilting the sample relative to a sample mounting surface of the sample stage. A second processing step of rotating the sample on the sample mounting surface and irradiating the sample with an ion beam to perform processing; and a step of extracting a sample piece obtained in the second processing step. Sample preparation method. 2. A system for irradiating a focused ion beam, a secondary particle detector for detecting secondary particles generated from a sample by the irradiation of the focused ion beam, and a sample stage on which the sample substrate is mounted. In a sample preparation method of separating or preparing to separate a micro sample from a sample using a sample preparation apparatus having at least the angle between the focused ion beam irradiation axis on the sample and the sample surface, the angle exceeding 0 ° and at most 9
The sample is irradiated with a focused ion beam at less than 0 degree, and then the sample is rotated about the sample surface normal as a rotation axis. The angle between the focused ion beam irradiation axis on the sample and the sample surface is fixed, and the sample is applied to the sample. A sample preparation method, which comprises irradiating a micro sample to separate or prepare for separation. 3. A method for preparing a sample for observation, analysis, or measurement, wherein an angle between an axis of irradiation of the focused ion beam on the sample and the surface of the sample is set to an angle exceeding 0 ° and at most less than 90 °. Irradiating the sample with a focused ion beam to form a square hole; rotating the sample around the sample surface normal as a rotation axis; and rotating the focused ion beam to rotate the sample obliquely with respect to the surface of the sample substrate. The step of forming the groove, the step of forming a cantilever sample held by the support portion on the sample substrate, and contacting a desired portion of the cantilever sample with a desired portion of the transfer means, and irradiating a deposition gas Irradiating a focused ion beam to a region including the contact portion to form a deposition film, thereby fixing the cantilever sample and a desired portion of the transfer means;
Cutting the support by irradiating the sample. 4. A method for preparing a sample for observation, analysis or measurement, wherein the angle formed between the axis of irradiation of the focused ion beam on the sample and the surface of the sample is greater than 0 ° and at most less than 90 °. A step of forming a square hole by irradiating an ion beam to form a thin film, a step of rotating a sample around a sample surface normal line as a rotation axis, and separating the sample thin film by focused ion beam irradiation after rotation, Or a step of preparing for separation. 5. A focused ion beam irradiation apparatus for a focused ion beam apparatus having at least a focused ion beam irradiation optical system and a sample stage on which a sample substrate is mounted, wherein the focused ion beam apparatus separates or prepares a minute sample from the sample substrate. It has a structure in which the angle between the general center axis of the mechanical column including the optical system and the mounting surface of the sample on the sample stage is fixed, means for separating a desired portion of the sample, and a probe for supporting the separated sample. A sample preparation apparatus, comprising: 6. An optical system for irradiating a focused ion beam, at least a secondary particle detecting means for detecting secondary particles generated from a sample by the irradiation of the focused ion beam, and a sample stage for mounting a sample substrate. In a sample preparation apparatus for separating or preparing for separation of a micro sample from a sample substrate, an angle between a focused ion beam irradiation axis on the sample and the sample surface is in a range of 30 ° to 75 °, and the sample stage is a sample surface method. A transfer unit that has a function of rotating the line as a rotation axis, and transfers the extracted microsample obtained by separating the desired portion of the sample substrate to another member; and a sample holder holding unit that mounts the microsample. A sample preparation apparatus comprising: 7. An optical system for irradiating a focused ion beam, a secondary particle detecting means for detecting secondary particles generated from a sample by the irradiation of the focused ion beam, and a sample stage on which a sample substrate is mounted. In a sample preparation apparatus for separating or preparing a minute sample from a sample substrate, the angle between the focused ion beam irradiation axis on the sample and the sample surface is more than 0 ° and at most less than 90 °, and the sample stage is It has a function of rotating the sample surface normal as a rotation axis, and the irradiation position of the focused ion beam for separating or preparing the sample after rotation is adjusted by the focused ion beam or an electron beam irradiation system provided separately. Has the function of using the result of image processing of the secondary particle image formed by the secondary particles generated from the sample. Fee producing device. 8. An optical system for irradiating a focused ion beam, at least a secondary particle detecting means for detecting secondary particles generated from a sample by the irradiation of the focused ion beam, and a sample stage on which a sample substrate is mounted. In a sample preparation apparatus for separating or preparing to separate a micro sample from a sample substrate, an angle between an axis of irradiation of the focused ion beam to the sample and the sample surface is more than 0 degree and less than 90 degrees at most, and the sample stage Has a function of rotating the sample surface normal as a rotation axis, and the irradiation position of the focused ion beam for separating or preparing the sample after rotation is adjusted by the irradiation of the focused ion beam or the electron beam irradiation system provided separately. It has a function to determine by using image display means for displaying a secondary particle image formed by secondary particles generated from a sample by a beam. Sample Preparation and wherein the door. 9. An optical system for irradiating a focused ion beam, a secondary particle detecting means for detecting secondary particles generated from a sample by the irradiation of the focused ion beam, and a sample stage on which a sample substrate is mounted. In order to separate or prepare to separate a micro sample from a sample substrate, the sample substrate is irradiated with a focused ion beam from a plurality of incident directions around the micro sample to separate or prepare to separate the micro sample. A sample preparation apparatus, characterized in that the focused ion beam irradiation optical system has a focused ion beam tilting function capable of changing a focused ion beam irradiation axis on a sample by at least 15 degrees. 10. The sample preparation apparatus according to claim 9, wherein the focused ion beam tilting function of changing a focused ion beam irradiation axis on the sample by at least 15 degrees is realized by an electric deflection mechanism.