JP2007064812A - Probe for inspection device, and method for manufacturing same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cantilever capable of solving a noise in an image caused by buckling and bending of a carbon nanotube, that is a problem in observation of a sample surface by an atomic force microscope (AMF) or the like using the cantilever with the carbon nanotube, so as to acquire a stable AFM image, and the AFM of high resolution using the same. <P>SOLUTION: The present invention provides the cantilever with the carbon nanotube with a metal layer deposited on the carbon nanotube from at least opposed two directions in the vicinity of a tip of the cantilever, and a manufacturing method therefor. Resultingly, an exposed length of a carbon nanotube probe is controlled to prevent the carbon nanotube from being buckled when contacting with a sample. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a probe for an inspection apparatus using a carbon nanotube as a probe and a method for manufacturing the probe.

An atomic force microscope (AFM) is a type of scanning probe microscope. An example of an AFM is a device that measures a surface state by mounting a cantilever with a sharp tip, bringing the sample into contact with the cantilever probe, and scanning the sample. It has a feedback mechanism that raises and lowers the cantilever or the sample so that the state at the time of contact is constant. As a result, the surface state (for example, unevenness) of the sample can be measured from the control signal. Other,
The SPM includes a scanning tunnel microscope and a scanning near-field optical microscope.

  A cantilever using a carbon nanotube as a probe is being adopted for AFM and SPM including AFM. Carbon nanotubes have a high aspect ratio cylindrical structure with a constant diameter, and the diameter of the tip of the probe that contacts the sample and the angle with the sample surface do not change due to wear and damage of the probe tip in use This is because it has an advantage (fine bundle) that a high spatial resolution can be maintained.

Conventional cantilevers with carbon nanotubes irradiate hydrocarbon-based impurities existing inside a scanning electron microscope with an electron beam as shown in Japanese Patent No. 3441396 (Patent Document 1) and Japanese Patent No. 3441397 (Patent Document 2). Thus, a method of manufacturing a cantilever with a carbon nanotube has been used by depositing in the vicinity of the carbon nanotube and fixing the carbon nanotube to a base material. Also, JP 2002-162337 A
According to (Patent Document 3), the carbon nanotube is fixed to the cantilever by disposing the carbon nanotube on the cantilever and further irradiating the hydrocarbon existing inside the scanning electron microscope with an electron beam. It has a stacked structure. Further, according to the cited document 3, focused ion beam processing is used for fixing the carbon nanotube probe fixed to the cantilever. In another method, Japanese Patent Application Laid-Open No. 2003-90788 (Patent Document 4) forms a catalytic metal film on a cantilever and uses a catalytic action to form carbon nanotubes on the cantilever. In this method, since the catalyst metal becomes a supersaturated solid solution of carbon, the catalyst metal is changed to a carbide, so that the conductive characteristics required for the metal cannot be expected. In Japanese Patent Application Laid-Open No. 2005-62007 (Patent Document 5), a carbon nanotube is formed by immersing a cantilever pyramid-shaped holder in an organic solvent. In JP-A-2005-63802 (Patent Document 6), low resistance is realized by metal bonding of carbon nanotubes after removing a high-resistance surface layer such as a natural oxide film generated on the surface of the holder portion.

Japanese Patent No. 3441396 Japanese Patent No. 3441397 JP 2002-162337 A JP 2003-90788 A JP 2005-62007 A JP-A-2005-63802

  The AFM operation method detects the surface condition of the sample by moving the cantilever or the sample up and down so that the probe and the sample surface come into contact with each other with a set fixed approach load and discontinuously contacting the probe with the sample surface. Method (step-in mode), a method of detecting the surface state of the sample by contacting the probe surface with the sample surface and tracing continuously or discontinuously (contact mode), forcing the cantilever to vibrate and tapping the sample surface There are various methods such as a method (dynamic mode) for detecting the surface state of the sample from changes in amplitude, phase, vibration frequency, etc., which are selected and used depending on the sample and the surface state of the sample. In these operation modes, when carbon nanotubes are used for the probe, buckling or bending of the carbon nanotubes becomes a problem. The bending of the carbon nanotube means that the carbon nanotube bends when a lateral force acts on the carbon nanotube, and the buckling means that a constant buckling occurs when a vertical approach load acts on the carbon nanotube. It means that sudden lateral bending occurs at the moment when the bending load is reached.

  The approach load is generally detected by detecting the deflection amount of the cantilever by a method called an optical lever method. For this purpose, the spring constant of the cantilever is selected so that the amount of deflection can be sufficiently detected.

  In each mode, if the setting of the approach load of the carbon nanotube probe is not appropriate and excessive, bending or buckling occurs when the carbon nanotube contacts the sample. Therefore, the surface state of the sample cannot be accurately detected, and an image representing the surface state of the sample obtained as a result of the measurement can be obtained as an image having a shape different from the original surface shape of the sample, or the carbon nanotube can be searched. Problems such as the needle peeling off from the cantilever and being unable to continue the measurement occur.

  In order to eliminate buckling, the approach load of the cantilever needs to be set smaller than the load at which buckling of the carbon nanotube occurs (buckling load). On the other hand, the spring constant of the cantilever is as described above. It is necessary to be able to be sufficiently bent by the load. Considering the strength of the entire cantilever and its material, it is difficult to make the spring constant of the cantilever lower than the current level. Particularly in the dynamic mode, if the spring constant is lowered in order to vibrate the cantilever at a high frequency, the measurement accuracy may be lowered. Therefore, it is necessary to increase the buckling load of the carbon nanotube portion.

  In order to eliminate the bending, it is necessary to set the cantilever approach load small so that the lateral force acting on the carbon nanotubes does not affect the measurement accuracy, while the cantilever spring constant is As described above, it is necessary to be sufficiently bent by the approach load. Considering the strength of the entire cantilever and its material, it is difficult to make the spring constant of the cantilever lower than the current level. For this reason, it is necessary to increase the strength against bending of the carbon nanotube portion.

  An object of the present invention is to provide a cantilever having a carbon nanotube probe which is not easily buckled and has high strength against bending, and a probe for an inspection apparatus, AFM, and broadly an SPM using the cantilever.

  A feature of the present invention that solves the above problems is that the tip of the cantilever and the carbon nanotube are fixed at least in two directions using a metal layer, and the metal layer is deposited in an arbitrary range on the carbon nanotube. That is. By depositing metal from two directions, the exposure range of the carbon nanotube can be adjusted, and buckling and bending can be prevented.

  Therefore, another feature of the present invention resides in a manufacturing method in which a metal layer is laminated from at least two directions on a fixed portion at an end of the cantilever to which the carbon nanotube probe is fixed.

  The metal layer is for depositing a product by decomposing a metal compound gas by electron beam irradiation. Specifically, the metal layer can be formed of W, Pt, Au, Al, Cu, Mo or the like. In particular, a tungsten bonding layer is preferable. This is because by using a metal layer, particularly tungsten, the bonding strength is improved as compared with the hydrocarbon adhesive. In addition, since the conductivity between the carbon nanotube and the cantilever can be ensured by joining the metal layers, it is possible to prevent the joint from being broken due to charging. The metal layer is preferably higher in purity, but can be sufficiently fixed if the content is 70% or more.

The above-mentioned joining is for introducing a cantilever and a sample chamber under vacuum or reduced pressure into which carbon nanotubes are put, and gaseous W (CO) ₆ or WF ₂ that is heated and vaporized as a raw material for the metal layer into the sample chamber. This can be achieved by an apparatus for producing a cantilever with a carbon nanotube, comprising a gas introduction device and an electron beam irradiation device that irradiates an electron beam that decomposes the gas.

Another feature of the present invention resides in a scanning probe microscope to which the cantilever is applied. The scanning probe microscope can be used as an inspection device such as a semiconductor inspection device, a DVD pit inspection device, a non-aberration lens inspection device for a CCD camera, a roughness meter, a bio-observation, or a polymer non-destructive observation device. The present invention also resides in an LSI manufacturing apparatus that employs the above-described scanning probe microscope as an inspection apparatus section. Scanning probe microscopes include manipulators and CD-
It can be used with different names such as AFM.

  An LSI is a circuit in which many transistors are integrated. In particular, a circuit is constructed by repeating the three steps of (1) chemical vapor deposition, (2) etching, and (3) surface inspection. The surface state of the LSI being formed can be inspected in detail using the inspection apparatus after the etching.

  According to the cantilever with a carbon nanotube of the present invention and the manufacturing method thereof, the measurement defect caused by the bending and buckling of the carbon nanotube, which has been a problem in the measurement by the AFM using the cantilever with the carbon nanotube, for example, the result of the measurement As a result, an image having a shape different from the original surface shape of the sample can be obtained, the destruction of the carbon nanotube junction caused by charging, image failure, and the like can be solved, and stable AFM measurement can be performed.

  Therefore, an atomic force microscope that enables high-accuracy and high-resolution measurement can be achieved by taking advantage of the tightness of the carbon nanotubes.

  Furthermore, since the cantilever can be extended in life, high accuracy, high resolution, and stable measurement over a long period of time are realized, and high-precision shape measurement (inspection process) is required in the manufacturing process like LSI. The production of the product to be made possible.

  Hereinafter, the cantilever of the present invention will be described in detail.

  A probe for an inspection apparatus such as an AFM has a base fixed to the AFM main body, a cantilever protruding from the base and deflecting in accordance with an approach load, and a probe fixed to the tip of the cantilever. The probe of the present invention used carbon nanotubes. You may provide the holder used as the foundation for fixing a probe suitably in the front-end | tip part of a cantilever. As a result, it is possible to easily set the rough direction of the cantilever and the probe.

  As described above, a feature of the present invention is that a metal layer is deposited from at least two directions, and a carbon nanotube is fixed to the tip of the cantilever or holder that faces the sample during measurement. The above-mentioned two directions need to be directions that can hold the carbon nanotube at the tip in any direction, and are preferably opposite directions. The opposite direction is, for example, the case where two metal layers are provided in the direction of about 180 degrees at the base part (cantilever end part or holder end part) of the carbon nanotube, or the case where three metal layers are provided in the 120 degree direction. Can be considered.

  Examples of the holder include a pyramid-shaped polygonal cone, a cone, and a columnar shape. Further, the tip of the holder may be cut and thinned into a needle shape for use. In particular, in the case of the weight shape, the carbon nanotube can be fixed by depositing a metal layer from an arbitrary direction at the top of the holder and fixing it so that the next metal layer is deposited at least on the back side of the carbon nanotube (opposite 180 °). It is preferable for easy fixation and position maintenance of the carbon nanotube. In order to achieve the “two opposing directions”, the metal layer can be deposited by turning the cantilever about 180 ° and then depositing the metal layer. Since the metal layer is deposited from a plurality of directions, for example, when the carbon nanotube is bent during the deposition of the first metal, the bent tip can be adjusted by the deposition of the second layer of metal. It is easy to fix by adjusting the angle of the probe. The same applies to the case where the tip of the cantilever is processed into a shape similar to the holder shape.

  Hereinafter, the above two directions will be described in detail.

  The plane formed by the sample support and the probe must be at an arbitrary angle, for example, an arbitrary angle determined by the vertical or measurement target. Therefore, it is necessary to refract the probe according to the shape of the fixed portion or to keep the probe linear. When the carbon nanotube is refracted at the tip of the cantilever (or the apex portion of the holder tip), the carbon nanotube has a major angle greater than 180 degrees and an obtuse angle smaller than 180 degrees. The two directions described in the present invention mean at least the obtuse angle side and the dominant angle side of the refracted portion of the carbon nanotube. In the case where the refraction is not performed, the carbon nanotube side and the cantilever side when the carbon nanotube and the cantilever tip are brought into contact are referred to.

  The obtuse angle metal layer (support joint) is a support layer for fixing the carbon nanotubes, and is a metal layer necessary for improving the bond strength of the carbon nanotubes to the cantilever.

  The metal layer (press bonding portion) on the dominant angle side has a function of pressing the carbon nanotube against the cantilever and maintaining the direction of the probe. Also, depositing the metal layer on the dominant angle side after the obtuse angle side means that the probe tilted from a desired fixed angle can be deposited on the metal layer on the dominant angle side by the holding force of the metal layer deposition on the angle side. This is desirable because it can be adjusted by pressing. Furthermore, it can be adjusted with high accuracy to an angle suitable for the measurement object and / or measurement mode.

  Further, by selecting an appropriate deposition condition of the metal layer, it is possible to wrap around the metal layer not only in the electron beam irradiation direction but also in a portion reaching the opposite side. That is, the metal layer on the dominant angle side and the obtuse angle side is deposited from any one direction so that the cross-sectional shape of the pencil has the probe as the core and the outer skin part as the metal layer. A deposited structure can be formed. By appropriately selecting the deposition conditions, it is possible to provide a probe with high yield and easy manufacture.

  The carbon nanotube is fixed on the ridge line or the side surface if the end of the cantilever or the holder to be fixed is a polygonal pyramid. For example, when fixing a carbon nanotube to a pyramid-shaped holder, the end of the carbon nanotube opposite to the side in contact with the sample is fixed on the ridgeline or the side surface, and fixed to the holder tip at several locations along the ridgeline or side surface. The holder tip is bent at an arbitrary angle with respect to the plane formed by the sample support of the measurement apparatus main body. The closer the angle between the probe angle and the sample table plane is to be vertical, the more the bottom can be measured even with deep irregularities. For measurement of a deep uneven surface, it is preferable that the inclination is vertical or within 3 degrees from the vertical direction.

  In addition, the boundary between the bottom of the groove or hole formed on the sample and the side wall is fixed by inclining and fixing at a certain angle of 90 degrees or less from the direction perpendicular to the sample table plane according to the sample shape, for example, 30 degrees. The vicinity of the part and the side wall can be measured. The direction of tilting is adjusted according to the surface shape of the sample in the front-rear and left-right directions in the direction of travel of the probe on the sample. By tilting the probe back and forth and / or right and left in the traveling direction, the boundary portion and the side wall portion facing the tilted direction can be clarified. Furthermore, for a sample having a shape (overhang) portion in which the upper portion of the side wall protrudes, the overhang portion can be measured by tilting and fixing the probe and appropriately setting the approach direction of the cantilever.

The metal layer is formed by depositing the various metal compounds described above. In the case of tungsten, the carbon nanotube and the cantilever are brought into contact, and a gas obtained by heating and vaporizing W (CO) ₆ or WF ₂ is introduced into the sample chamber of the operation electron microscope having a high degree of vacuum, and the W (CO) ₆ or WF ₂ gas is discharged near the contact portion using a nozzle, the atmosphere of the gas is formed near the contact portion, and the contact portion is irradiated with an electron beam to decompose the gas. Then, it can be achieved by depositing the deposited tungsten on the contact portion which is an irradiation region.

  By setting the intensity of the electron beam for decomposing the gas within a certain range, a metal layer that wraps around to the back side of the carbon nanotube can be deposited, which is preferable for improving the strength.

  The electron beam intensity is adjusted by the acceleration voltage and the total current of the electron beam to be irradiated. As the acceleration voltage is increased, the deposition of the metal layer is biased toward the electron beam irradiation side, and the wraparound to the opposite side of the carbon nanotube is reduced. Therefore, the acceleration voltage is desirably 15 kV or less. Also, as the total current increases, anything tends to be deposited. Therefore, it is desirable that the total current be 20 μA or less in order to reduce the deposition amount of contaminants and provide a deposition layer having a sufficient strength with a metal component content of 70% or more.

  The thickness of the metal layer is made thick enough for fixation, but it is desirable for the metal layer to be present at least twice the thickness of the carbon nanotube in order to prevent buckling. For example, when the radius of the carbon nanotube is 5 nm, the metal layer is preferably 10 nm or more. As a result, the metal layer surrounds the carbon nanotube having a diameter of 10 nm, and the entire outer diameter is preferably set to 3 times the diameter (30 nm) or more. The height of the metal layer needs to be deposited so that the range of exposed carbon nanotubes is reduced. The metal layer is preferably deposited so that the carbon nanotubes are held substantially in the center. This is because if the carbon nanotube is eccentric in position, there is a high possibility that the metal layer is broken from a portion where the metal layer of the carbon nanotube is thin.

  Next, a method for using the probe in the measuring apparatus will be described. The probe is fixed at a position where the sample stage for fixing the sample to the measuring apparatus main body and the probe are opposed to each other, and the measuring apparatus has a driving mechanism for moving the sample stage and / or the cantilever toward or away from both. .

  In a measuring apparatus such as an AFM, the cantilever is brought close to the sample up to a load that pushes the cantilever against the sample (approach load). Even if the probe and sample contact, the cantilever is pressed against the sample, and as the approach load increases, the cantilever deflects as a leaf spring, and the amount of deflection and displacement of the base are detected by a detector. When the value is equal to the set condition (the state when the set approach load condition is applied), the cantilever pressing is stopped by the signal fed back from the detector.

  A measuring device using a probe obtains information in the height direction, for example. If the carbon nanotube buckles or bends differently from time to time, the carbon nanotube fixed side (free end side) of the cantilever sinks more than necessary, so the height of the carbon nanotube fixed side (free end side) of the cantilever relative to the sample surface Change. Therefore, an error occurs in the detected information in the height direction. As a result, the reliability of the acquired information is hindered.

  For accurate measurement, carbon nanotubes need to remain constant at a set approach load. For example, when the carbon nanotube is pressed against the sample a plurality of times, an accurate surface state can be detected by setting a constant state (curved state, linear state, etc.) for each contact.

  When the lower end of the carbon nanotube is in contact with the sample, an approach load is applied to the carbon nanotube from the base through the cantilever, and compressive stress is generated. When the approach load reaches the buckling load of the carbon nanotubes, the carbon nanotubes cannot maintain a constant state and suddenly buckle and buckle. The buckling of carbon nanotubes is caused by excessive lateral bending stress when slippage occurs on the sample surface that is in contact with the tip of the probe, causing the carbon nanotube root part (the part fixed to the cantilever) to Most of the cases are buckling and bending, and no slipping and intermediate part buckling.

  As described above, since the approach load of the cantilever needs to be a certain value or more, it is necessary to increase the strength against buckling resistance and bending. Since the strength against buckling resistance and bending is proportional to the fourth power of the thickness, prevention of buckling and bending can be prevented by increasing the diameter of the carbon nanotube. However, increasing the thickness of the carbon nanotube itself is contrary to the purpose of improving the spatial resolution by utilizing the thinness of the carbon nanotube. Since buckling resistance and strength against bending are inversely proportional to the square of the length (the strength against buckling load and bending decreases as the length of the carbon nanotube increases), buckling can be achieved by shortening the length of the carbon nanotube. And avoid bending.

  In the above-described cantilever of the present invention, the exposed portion of the carbon nanotube as the probe is shortened by the deposition of the metal layer. In the manufacture of probes, the process of cutting carbon nanotubes to a desired length (pulse voltage application, cutting by energization, etc.) is known, but it is difficult to excise with accuracy, and the desired buckling limit is accidentally caused. Therefore, the yield is poor because a material having a stress lower than that is selected. If the range fixed with a metal layer is heightened as mentioned above, since an exposed part will be shortened, probe length can be adjusted.

  In this embodiment, an example in which one carbon nanotube probe 11 is fixed by a metal layer at the tip of the holder 15 is shown. FIG. 1 is a perspective view of a probe portion of a probe according to the present invention. FIG. 2 shows an overall view of the probe including the cantilever probe portion described in FIG. As shown in FIG. 2, the probe has a portion (tip) composed of the carbon nanotube probe tip 11, the tip joining layer 12, the intermediate joining layer 13, the end joining layer 14, and the holder 15 on one of the cantilevers 16 (free end). ) And the base 18 is disposed on the other (fixed end). The metal layers of the intermediate bonding layer 13 and the terminal bonding layer 14 act as a fixing layer for fixing the probe to the holder 15.

  FIG. 3 is a cross-sectional view of FIG. As shown in FIG. 3, the tip bonding layer 12 is classified into a support bonding layer 19 on the obtuse angle side and a pressure bonding layer 20 on the dominant angle side by its action. The support bonding layer 19 has the function of fixing the probe to the holder in the same manner as the bonding layers 13 and 14. The pressure bonding layer 20 has a function of pushing back a restoring force for the carbon nanotubes to return to a straight line. The carbon nanotube probe 11 is fixed substantially perpendicular to the plane 17 formed by the sample support.

  If the probe is not parallel to the pressing direction or if the tip of the probe slips, the carbon nanotube will bend according to the approach load without buckling resistance. Since the linear extension direction of the carbon nanotube probe 11 is substantially perpendicular to the plane 17 formed by the sample support base, slipping is particularly reduced.

When tilting the probe while obtaining the effect of preventing slipping, it is appropriate that the angle is within 5 degrees from the vertical direction. Especially within 2.5 degrees is desirable. The friction resistance between the carbon nanotube probe and the sample surface is often 1 nN or more. The load in the sliding direction applied to the carbon nanotube probe needle is 0.03622 (sin 2.5 °) times the approach load at 2.5 degrees, and 0.08716 (sin 5 degrees) times at 5 degrees, and there is a difference of about twice. . For example, for an approach load of 20 nN, the lateral sliding loads are 0.8724 nN and 1.7432 nN, and if the friction resistance of the carbon nanotube probe is 1.0 nN, it will not slip at 2.5 ° and 5 °. Then slip occurs. If the probe angle is 5 ° or less, it seems possible to produce a cantilever that can be used with reduced slip in most devices.

  As described above, since the load in the sliding direction depends on the approach load and the inclination of the probe, it is desirable that the approach load be set to a load that does not cause slipping. However, it is necessary not to reduce the approach load beyond the limit of load detection accuracy peculiar to the measuring device.

  The carbon nanotubes 11 were fixed along the ridge line of the holder 15 in the order of the end bonding layer 14, then the intermediate bonding layer 13, and finally the tip bonding layer 12. As the tip bonding layer, a metal layer was deposited from two directions. In the present embodiment, the carbon nanotube probe 11 is fixed along the holder 15 at three points by the dotted metal layer, but can be appropriately changed depending on the length of the carbon nanotube and the size of the metal layer. A plurality of carbon nanotubes may be used as a bundle.

  In this example, tungsten was used as the metal layer.

The introduced tungsten compound gas is W (CO) ₆ , and the irradiated electron beam has an acceleration voltage of 10 V and an emission current of 12 μA. The electron beam irradiation time is about 15 seconds. The holder was made of silicon (Si) and was processed into a pyramid shape. The metal layer thickness can be adjusted by the electron beam irradiation time, and sufficient fixing strength can be achieved in 10 to 30 seconds.

  FIG. 4 shows the result of component analysis of the metal layer. As a result, 90% or more of tungsten was contained. The bonding strength was measured and found to be sufficient for use. The W of the metal layer was detected with a scanning Auger electron spectrometer (PH1700 manufactured by ULVAC-PHI) and mapped to confirm the metal layer.

(Comparative Example 1)
An apparatus similar to the probe shown in Example 1 was prepared by changing the metal layer from only one direction.

  As described above, the metal layer was tungsten and the carbon nanotubes were fixed by the same method, but the tip joining layer was only in one direction.

  The tip of the carbon nanotube probe was cut by applying a pulse voltage.

The scanning electron microscope (Scanning) in which the probe of Comparative Example 1 was used for deposition of a metal layer.
Electron Microscope). As a sample, an Au wire having strong corrosion resistance and excellent conductivity was used as an observation sample. The Au wire was used by cutting the tip with a nipper. The cross-sectional shape of the cut portion was wedged by cutting, and the flat portion of the wedge-shaped side surface was used as the sample plane. A part other than the sample plane of the Au wire was partially bent in the right angle direction so that the sample plane and the probe faced each other.

  In order to observe the measurement state, the probe was rotated 90 degrees with the cantilever kept horizontal, and the operation was performed at a position where an image similar to the projection view of FIG.

Without moving the probe, the sample support was moved to bring the smooth surface of the Au wire closer to the probe.
Even after the Au wire contacted the probe, the wire was moved until the load corresponding to the force corresponding to the actual approach load was reached. As a result, buckling of the carbon nanotube was observed during the measurement.

(Comparative Example 2)
A device similar to the probe shown in Example 1 was joined by replacing the metal layer with a conventional carbide layer (contamination). As a result, the carbon nanotube probe 11 was peeled off during use. FIG. 5 shows a situation explanatory diagram when the probe of this comparative example is operated with an actual machine. Au wire was used as a sample.
(A) shows a process in which the probe approaches. The carbon nanotube probe tip 11 approaches the Au surface, but has not yet contacted the Au surface.
(B) shows a process in which the carbon nanotube probe 11 comes into contact with the Au surface and is pushed to the initial approach load.
(C) shows the process of detaching the probe after reaching the approach load. Unlike the approach, the tip of the carbon nanotube probe 11 was adsorbed to the sample while pulling the cantilever with a force that seems to be adsorbed by static electricity.
(D) shows the moment when the carbon nanotube probe 11 is separated from the Au surface. Since the cantilever 16 was pulled by the suction, a restoring force was applied to the cantilever 16 at the moment of separation, and vibrated vigorously. According to SEM observation, the image of the probe was not clear due to vibration. Further, the carbon nanotube probe needle 11 dropped off due to vibration at the time of separation. When each joint layer portion after dropping was observed, it was in a ruptured state.

  When the metal layer (tungsten) was deposited, the adsorption of the carbon nanotubes did not occur.

  Therefore, the above phenomenon seems to be due to electrification, and the detachment of the carbon nanotubes seems to be the result of an electrostatic discharge phenomenon. In the carbon nanotube of the present invention, it is considered that the carbon nanotube probe 11 was not charged due to the fixation by metal, and such adsorption and breakage could be avoided. Therefore, the durability of the product can be improved and the service life can be extended. Furthermore, high accuracy of measurement can be expected.

The perspective view of the structure of the probe of the cantilever end part of the probe concerning this invention. The whole figure of the probe concerning the present invention. Sectional drawing of the cantilever end part of FIG. Elemental analysis results of components contained in tungsten metal layer. FIG. 5 is a continuous view of a sample contact during AFM image acquisition of a probe in which a tungsten metal layer is changed to fixation by a carbide layer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Carbon nanotube probe, 12 ... Tip joining layer, 13 ... Intermediate joining layer, 14 ... End joining layer, 15 ... Holder, 16 ... Cantilever, 17 ... Sample support stand, 18 ... Base, 19 ... Support joining layer, 20 ... Pressing bonding layer.

Claims (12)

A probe for an inspection apparatus having a base fixed to the inspection apparatus, a cantilever formed to protrude from the base, and a probe fixed to the tip of the cantilever,
The probe for an inspection apparatus, wherein the probe is a carbon nanotube, and the probe is fixed by a metal layer from at least two directions in a state of protruding in a direction in which a sample is fixed.   2. The probe for an inspection apparatus according to claim 1, wherein the metal layer contains tungsten hexacarbonyl or a decomposition product of tungsten fluoride as a main component, and the content of tungsten is 70% or more.   The probe for an inspection apparatus according to claim 1, further comprising a holder fixed in the vicinity of a protruding tip portion of the cantilever, and a probe fixed on the holder.   4. The inspection apparatus probe according to claim 3, wherein the holder has a conical shape, a polygonal pyramid shape, a columnar shape, or a shape in which the tip of any one of the shapes is a needle shape.   5. The cantilever according to claim 1, wherein the probe is fixed perpendicularly to a sample table plane for fixing a sample or inclined at an angle of 5 degrees or less with respect to a vertical direction. A probe for an inspection apparatus, characterized by comprising:   A method of manufacturing a probe for an inspection apparatus having a polygonal pyramid-shaped tip with carbon nanotubes, wherein the carbon nanotube is brought close to the polygonal pyramid-shaped tip, and the carbon nanotube and the tip on the tip in the approached state. A method for producing a probe for an inspection apparatus, comprising: depositing a metal layer in at least two directions and shortening an exposed length of a carbon nanotube.   The method for manufacturing a probe for an inspection apparatus according to claim 6, wherein the tip of the polygonal pyramid is formed by processing a cantilever end or fixing a polygonal pyramid shaped holder to the cantilever. A method for manufacturing a probe for an inspection apparatus, comprising:   8. The method of manufacturing a probe for an inspection apparatus according to claim 6 or 7, wherein the metal layer is installed after tungsten hexacarbonyl or tungsten fluoride gas is decomposed by electron beam irradiation to obtain metal tungsten. A method for manufacturing a probe for an inspection apparatus, wherein the probe is installed by preferentially depositing tungsten on the electron beam irradiated portion.   The method for manufacturing a probe for an inspection apparatus according to claim 6 or 7, wherein the metal layer is at least on one end of the carbon nanotube and on a ridge line of the polygonal tip, and the carbon nanotube. The other end of the carbon fiber is deposited in the vicinity of the apex when pulled to the apex of the tip and the direction near the apex in the direction other than the ridge line direction when the carbon nanotube is bent and held thereafter. A method for producing a probe for an inspection apparatus.   The method for manufacturing a probe for an inspection apparatus according to claim 6 or 7, wherein the metal layer is formed on at least one end of the carbon nanotube and on a side slope of the polygonal pyramid tip, and the carbon. The vicinity of the apex when the other end of the nanotube is held and pulled to the apex of the tip, and the direction near the apex in a direction other than the inclined direction when the end of the carbon nanotube is bent and held thereafter The manufacturing method of the probe for test | inspection apparatuses characterized by performing to these.   6. A scanning probe microscope having a probe for an inspection apparatus having a carbon nanotube probe and detecting a surface state of the sample, wherein the inspection apparatus probe is the inspection apparatus according to any one of claims 1 to 5. A scanning probe microscope characterized by being a probe for use. A lamination step of laminating a semiconductor, a metal conductive layer, or an oxide and a nitride insulating layer on a substrate by chemical vapor deposition, an etching step of etching a part of the laminate to expose a cross section, and the etching A method of manufacturing an LSI having a surface inspection step for inspecting a surface shape after processing, and performing the laminating step and the etching step a plurality of times,
12. The LSI manufacturing method, wherein the surface inspection step is a step using the scanning probe microscope of claim 11.

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