JP4420273B2 - Integrated electronic device and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an integrated electronic device wherein the system is constructed by integrating a micron-rule or submicron-rule functional device structure on a system substrate, and to provide a method for manufacturing the same. <P>SOLUTION: A functional device manufactured on a substrate in a first process and having a plurality of input/output electrodes comprises a functional structure 21 formed separate from the substrate, a region 13 for mounting a functional structure 21; a substrate structure 10 manufactured in a second process and having a plurality of input/out electrodes to be connected to another plurality of input/output electrodes; and wires deposited by beam excited reaction for connecting the plurality of input/output electrodes of the substrate structure 10 and the plurality of corresponding input/output electrodes of the functional structure 21. The functional structure 21 is so designed that step formation is suppressed along the routes of the wires. <P>COPYRIGHT: (C)2005,JPO&amp;NCIPI

Description

  The present invention relates to an integrated electronic device that uses a very fine device structure in an integrated manner and a method for manufacturing the same.

  Miniaturization of electronic devices represented by Si-LSI is progressing year by year, and a fine electronic device having a size of 100 nm or less is about to be realized. In addition, a finer mechanical device represented by a micromachine is about to be manufactured.

  Currently, the size of LSI chips or micromachines realized by microfabrication technology based on lithography ranges from the wafer level (several tens of centimeters) to as small as about 100 microns. The larger one is determined by the wafer size, and the smaller one is determined by the handling limit. The constraints that determine this limit have not changed.

  On the other hand, LSI chips or micromachine component devices are rapidly miniaturized with the advancement of lithography. For this reason, the size of the assembly of devices necessary for realizing a certain function is reduced corresponding to miniaturization. For example, a functional device that has been integrated into a 10 mm square by a 1 micrometer-class microfabrication technology is expected to be realized after 2010, for example, if a 20 nm microfabrication technology is used, a 20 micron square It is possible to integrate in this area. Further, if the current processing technique of 100 nm class is used, it is possible to integrate 10,000 or more transistors in a 100 micrometer square, and it is possible to realize a functional device having a sufficiently high capacity.

  At present, even when a necessary functional device can be accommodated in a 100 micrometer square, it is necessary to use a chip of about 1 mm square or more because of restrictions on terminals for external connection and handling. This means that an unnecessary wiring having a length of 1 mm or more is required, which is a great burden (parasitic effect) for a fine device. Further, when a system in which a plurality of such functional devices are mounted is constructed, such a parasitic effect causes a large performance degradation.

  The advancement of device functions has created a demand for producing a single functional device by combining functional devices that have conventionally been produced in different chips by different processes. For example, a system that requires generation and transmission of a high voltage and a functional device group that operates at a low voltage may need to be integrated in the same chip. Although there is an aspect that is advantageous in terms of cost, there are many cases where it is desired to arrange them at high density due to a demand for higher speed. In this case, in order to realize devices manufactured by different processes on one wafer, a significant improvement of the process is required, and there is often no practical solution.

  As another example, it may be necessary to form a control or measurement circuit on a micromachine. In this case as well, it is necessary to integrate very different processes, which imposes great restrictions on each process, which is disadvantageous in terms of performance.

  As described above, in principle, with the miniaturization, there is a present situation where the merit cannot be used even though a highly functional device can be realized with a very small area. This is because there is a limit to the size that can be handled as a chip, and it is difficult to integrate the manufacturing processes of different devices.

  Integration of heterogeneous device manufacturing processes has many problems that are difficult to overcome. Therefore, another means different from the integration of the manufacturing process is desired. As one of the means, there is a means for lowering the limit of the size that can be handled as a chip and connecting the chips to construct a complex functional device system.

  First, let us consider a common overview of conventional technologies. Conventional compounding of different devices employs a technique in which components such as LSIs and resistors are appropriately arranged on a so-called board (substrate) and wired together. As shown in FIG. 14, even in the latest bare chip mounting, the functional device 101 cut out from the functional device substrate 100 which is a Si substrate is placed at a desired position on the printed circuit board 110, and the board pattern 111 and the functional device 101 are arranged. The connection terminals are connected by bonding wires 120 to perform wiring. In this case, due to the thickness and handling of the functional device substrate 100, the size that can be cut out from the Si substrate as the functional device 101 is about several hundred microns. Moreover, even if the electrodes for connection are small, there is a size of several tens of micrometers square per one, and this also limits the size that can be cut out.

  Advances in technology have made it possible to fabricate fairly sophisticated devices in the area of a few microns square. However, when such a functional device is assembled in the system, the area for connection to the system or the margin area for handling is larger than the size of the area of the functional device. In this case, a region other than the functional device acts as a parasitic effect on the functional device characteristics, and degrades the performance of the functional device.

  The same thing happens when testing fine functional devices. Since the structure used as the probe is too large for the functional device to be measured, a parasitic effect occurs, and accurate device performance measurement becomes difficult.

  In order to solve this, it is only necessary to cut out, handle, and connect a finer structure. Recently, in particular, a technique has been known in which a very fine structure can be easily cut out and handled by the development of a sample preparation method for a TEM (transmission electron microscope). For example, if a technique known as a microsampling technique (Patent Documents 1 and 2) is used, a structure of a micrometer order can be cut out, transferred, and placed at a desired position.

  In addition, as a connection method replacing the conventional wiring connection method such as wire bonding, a chemical vapor deposition method using a beam excitation reaction using FIB (focused ion beam) or SEM (scanning electron microscope). ) Can be used (Non-Patent Document 1). By utilizing these techniques, it becomes possible to handle a functional device on a fine structure of 100 μm or less and combine it with a base structure including other functional devices.

  However, a TEM sample preparation method represented by microsampling is a destructive inspection, and handling in a state where device performance is maintained is not considered. Further, the FIB wiring formation (defect correction) technique is a technique for forming a wiring at a place where wiring should already exist, and there has been no example of connecting different kinds of functional devices so far. For processing / handling (transfer) / wiring of functional devices, it is necessary to greatly improve and apply conventional microsampling or FIB wiring correction techniques.

  First, the sample preparation technique represented by the microsampling technique is in principle a destructive inspection. For this reason, there are some problems in applying the technology to the processing of functional devices. The most serious problem among them is beam damage. At the time of FIB processing at the time of sample preparation, a protective film is formed on the observation target in order to reduce beam damage. In general, the observation is not performed through the protective film, and the observation is performed from a direction perpendicular to the processed surface, so that the protective film does not hinder the observation. For this reason, after forming a sufficiently thick protective film on the observation target structure, the processing can be performed.

  However, such a protective film cannot be provided when a functional device, in particular, a micromachine device is manufactured. Further, even if the electronic device is already covered with a protective film such as a passivation film, direct irradiation of the beam has an influence on the device characteristics, so it is necessary to avoid it as much as possible. For this reason, when processing the functional device, it is necessary to devise such that the functional device region is not directly irradiated with the beam. Specifically, it is necessary to perform processing with the beam well squeezed. In particular, it is necessary to perform processing with a so-called flare beam having a beam intensity that is weak but is not negligible but that is as small as possible (mainly caused by aberrations in the extraction electrode system and the lens system). Even if the amount of flare is not a problem when preparing a TEM sample, there is a great problem when forming a microfabricated body. It is necessary to perform processing with an FIB apparatus and conditions that can reveal a situation where processing is possible without a protective film.

  In addition, special consideration is necessary for the wiring formation. Conventionally, in cutting out a chip from a wafer, a rectangular parallelepiped chip as shown in FIG. 14 has been cut out. When connecting the connection electrode on the structure and the electrode on the base structure, it is necessary to exceed a large step (structure film thickness). This is not a problem in the case of prior art wire bonding.

  However, in the metal deposition method using the beam excitation reaction by FIB, it is difficult to perform wiring formation beyond a large step. For this reason, it is necessary to be in a state where the step of the wiring connection portion can be ignored. Specifically, the step is made small so that exceeding the step is not a problem. That is, it is necessary to reduce the thickness of the processed body.

  Furthermore, when the electrodes are connected by wiring, it is necessary to clean the contact region in order to ensure the contact resistance of the connection portion.

Patent Document 1: International Publication Number WO99 / 05506 Patent Document 2: Japanese Patent Laid-Open No. 5-52721 Non-Patent Document 1: H. Langfischer, B. Basnar, H. Hutter and E. Bertagnolli, “Evolution of tungsten film deposition induced by focused ion beam,” J. Vac. Sci, Techonl. A 20 (4), Jul / Aug, pp.1408-1415, 2002.

  Miniaturization of functional devices will continue, and there is a possibility that the era of one device and one molecule will come in the future. In such an era, it is possible to realize a device having a high function even at about 1 micrometer square. In the field of device performance measurement, for example, as a probe for grasping the characteristics of a molecular device, it is sufficient that the tip diameter is 10 nm or less and the size is several hundred nm in total.

However, it is impossible to build a system by integrating such micron-level or sub-micron-level fine functional device structures on a system base to build a system. In order to solve this, a technique for solving the following three problems is mainly required.
(A) Cut out only the necessary parts of the micro functional device.
(Ii) A fine structure (several microns or less) including the cut out functional device is handled and installed on a base for constructing the system.
(Iii) Connect the electrode on the micro functional device and the electrode on the system board.

  The present invention solves the above-described problems and provides an integrated electronic device and a method for manufacturing the same, in which a micron-class or sub-micron-class fine functional device structure is integrated on a system base to construct a system. is there.

In order to solve the above-mentioned problem, the invention of claim 1 is characterized in that a functional device having a plurality of input / output electrodes manufactured on a substrate by a first process is formed by being separated from the substrate. A substrate structure having a region on which the functional structure is mounted and a plurality of input / output electrodes connected to the plurality of input / output electrodes, and manufactured by a second process; A wiring formed by beam excitation reaction deposition that connects the plurality of input / output electrodes and the corresponding plurality of input / output electrodes of the functional structure, and the functional structure includes a step in the path of the wiring There has been suppressed shape, the base structure is a cantilever of the scanning probe microscope probe, integrated electronic device according to claim Rukoto the functional structure to the tip of the cantilever portion is equipped with A.
According to a second aspect of the present invention, in the integrated electronic device according to the first aspect, the functional structure has a shape in which a side portion is inclined.
According to a third aspect of the present invention, there is provided the integrated electronic device according to the first aspect, wherein the functional structure has an inclined substrate surface on which the functional device and the input / output electrodes are formed, and has a wedge-shaped cross section. It is characterized by being.
According to a fourth aspect of the present invention, in the integrated electronic device according to the first aspect, the beam excitation reaction deposition is one of focused ion beam deposition and electron beam excitation deposition.
According to a fifth aspect of the present invention, in the integrated electronic device according to any one of the first to fourth aspects, the functional structure is a charge sensor.
A sixth aspect of the present invention is the integrated electronic device according to any one of the first to fifth aspects, wherein the functional structure is a single electronic device.
According to a seventh aspect of the present invention, there is provided a first step of cutting out a functional device having a plurality of input / output electrodes fabricated on a substrate by the first process from the substrate as a functional structure under a microscope; A second step of mounting the functional structure on a base structure having a plurality of input / output electrodes fabricated by a process; and fixing the functional structure to the base structure under a microscope; A third step of connecting the plurality of input / output electrodes of the body and the plurality of input / output electrodes of the functional structure by wires formed by beam excitation reaction deposition, and in the first step When the functional structure is separated from the base, the functional structure is separated from the base so that a step in the wiring path formed in the third step is suppressed. Which is a manufacturing method of an integrated electronic device for manufacturing the integrated electronic device according to any one of claims 1 to 6, wherein.
According to an eighth aspect of the present invention, in the method for manufacturing an integrated electronic device according to the seventh aspect , in the first step, the functional device is separated from the substrate in a shape in which a side portion is inclined.
According to a ninth aspect of the present invention, in the integrated electronic device manufacturing method according to the seventh aspect , in the first step, the cross-sectional shape is set so that the substrate surface on which the input / output electrodes of the functional device are formed is inclined. It is formed into a wedge shape and separated from the substrate.
The invention of claim 10 is the manufacturing method of the integrated electronic device according to any one of claims 7-9, in cut and disconnection of the functional devices in the first step, the focused ion beam It is characterized by using.
The invention of claim 11 is the method of manufacturing an integrated electronic device according to any one of claims 7 to 10 , wherein in the third step, either one of focused ion beam deposition and electron beam excitation deposition is used. The functional device is fixed or electrode-connected to the base structure using the deposited film formed by the above.

  In the present invention, the functional device manufactured on the substrate is transferred and fixed to the base structure manufactured by another process in the first to third steps. A system can be constructed by integrating functional device structures on a system board. In the present invention, when the functional device is separated from the substrate, the side portion of the functional structure is inclined, or the wiring connection portion of the functional structure is processed into a wedge shape so that there is no step with the base structure. Therefore, the functional device can be reliably provided on the base structure.

  According to the present invention, a microstructure including an ultrafine device having a plurality of electrodes is cut out using an arbitrary shape processing (etching / film deposition) function of the focused ion beam apparatus, and this is divided into the corresponding plurality of electrodes. By installing and wiring on the substrate structure having the above, it is possible to realize a high-performance composite electronic device that has never existed before. Its application range is wide, and it can be applied from electronic circuits to special measurement instruments such as measurement and scanning probe microscopes. Since the base structure and the fine structure are manufactured separately, there are no various restrictions in manufacturing, and high function integration is possible.

  Furthermore, in the present invention, the fine structure is processed into a wedge shape so that the side of the fine structure is inclined and the substrate surface is inclined so that there is no step between the wiring connection portion and the base structure. Therefore, the connection between the fine structure and the substrate structure can be ensured.

  Next, an embodiment of the present invention will be described. In the present embodiment, a focused ion beam processing machine is used as a method for solving the above three problems (a) to (u) for enabling system construction using a micro functional device.

  Conventionally, a focused ion beam (FIB) apparatus has been used for wiring correction of an integrated device, pattern correction of a photo master, processing of a cross-sectional TEM sample, and the like. Etching and film deposition by gas introduction can be performed by high-speed ion beam irradiation. In addition, by scanning the beam, it is possible to process and form an arbitrary shape.

  In recent years, the minimum processing dimension has been rapidly improved by improving the ion optical system and gas introduction method of the FIB apparatus. At present, both etching and film deposition are performed to a thickness of less than 100 nm, and the FIB apparatus is almost the only method that can directly process and form a micron-order structure. By using this FIB apparatus and the manufacturing method of the present invention, the above three problems (a) to (u) can be solved, and integration of the target functional devices can be realized.

  In this embodiment, first, only a necessary part of a micro functional device manufactured on a substrate using an existing technique is cut out using FIB. At present, it is possible to cut out an ultrafine structure having a minimum width of 100 nm, a length of several microns, a height of several microns, and a maximum of several tens of microns. If the structure is within the processing performance of the FIB, the cutout shape has a considerable degree of freedom.

  Furthermore, in this embodiment, when cutting out, in order to ensure the wiring to the electrode for connecting the micro functional device, the side of the ultrafine structure is inclined, and the substrate surface is inclined. The ultrafine structure was processed into a wedge shape so that there was no step between the wiring connection portion and the base structure. A wiring connection part is a wiring path | route with respect to the electrode of a micro structure. By such processing, the connection between the ultrafine structure and the substrate structure can be ensured.

  Next, the ultrafine structure including the micro functional device cut out by FIB processing is picked up by an appropriate probe, and moved to a predetermined position on the base for system construction and fixed. For fixing, a deposited film by FIB can be used. A connection electrode is prepared in advance on the base for system construction.

  Finally, the FIB deposited film connects the electrode on the ultrafine structure and the electrode on the system construction base. Since there is no step between the wiring connection portion of the ultrafine structure and the base structure when connecting the electrodes, a deposited film for wiring can be reliably formed.

  The system including the micro functional device can be configured by the above procedure. The major difference between this method and the prior art is not only that the FIB apparatus is used for processing and wiring, but also that the operation of integration is performed under a microscope because the target micro functional device is fine. Further, since there is no step between the wiring connection portion of the ultrafine structure and the base structure, a deposited film for wiring can be reliably formed.

  Using this system configuration technology, for example, a new type of pole that is difficult to integrate with a conventional CMOS process such as a single electron device or a carbon nanotube device, for example, with a part of functional blocks of a conventional CMOS-LSI. It can be replaced with a micro functional device. This technique can also be applied to device performance evaluation or failure analysis. For example, it is possible to evaluate the performance of a device with a high degree of accuracy by preparing a base that includes a circuit capable of measuring various performances of a micro functional device and then integrating the micro functional device to be measured on it. is there.

  Furthermore, this technology can be applied to fields other than electronic devices such as LSI. For example, a device for evaluating minute physical properties can be mounted on a probe of a scanning probe microscope. Alternatively, a measurement device can be installed in the microchannel on the quartz substrate.

  The background of the present invention is the rapid advancement of nanofabrication technology that allows the structures handled by FIB technology to operate as functional devices. With the advancement of both technologies, the application area of the present invention is expected to expand in the future.

Reference example 1

In this reference example, an Si single electronic device circuit on an LSI is taken as an example. First, as shown in FIG. 1, a CMOS-LSI 10 serving as a base structure is manufactured by a conventional technique. In the CMOS-LSI 10, functional circuit blocks 11 and electrodes 12 are formed. At the design stage, a mounting area 13 of about 10 μm square is provided for mounting the ultrafine functional device. Around the mounting region 13, a plurality of electrode structures for exchanging input / output electric signals between the CMOS-LSI and the ultrafine functional device are formed. This electrode structure is composed of a connection electrode 13A.

Furthermore, an ultrafine functional device is manufactured separately. In this reference example, as shown in FIG. 2, an ultrafine functional device 21 </ b> A that is a Si single electronic device is formed on the ultrafine functional device substrate 20. This device is described in the following reference 1.
Reference 1: Y. Takahashi, M. Nagase, H. Namatsu, K. Kurihara, K. Iwadate, Y. Nakajima, S. Horiguchi, K. Murase and M. Tabe: Electron. Lett. 31 (1995) 136.

  The Si single-electron device can be manufactured with the same equipment as a normal CMOS-LSI. However, since the structural parameters of the Si single electronic device are greatly different from those of the CMOS, it is difficult to mount the Si single electronic device on the same substrate as the CMOS device. In addition, one single-electron device has an extremely small portion of 10 nm square that is indispensable for operation, and has a unique characteristic that the current flowing through the device is periodically modulated by the gate voltage. In the configuration, a circuit configuration different from the conventional one is possible, and the same logic as the CMOS circuit can be realized with a small number of elements. Furthermore, since it is a low power consumption device in principle, a high density arrangement is possible. For this reason, a sufficiently high-functional device can be manufactured even with a size of about 10 μm square.

  Si single-electron devices have the above-mentioned advantages, but also have a disadvantage of low driving capability. Since the driving capability is small, it is difficult to use a single-electronic device as an output device. Even when a logic circuit is configured with a single electronic device, in order to perform an efficient circuit operation, the output circuit must be configured with a CMOS circuit or the like to amplify the output of the single electronic device.

Therefore, in this reference example, an example is shown in which an ultrafine device having an ultrafine functional device 21 </ b> A and an input / output terminal 21 </ b> B, which is a logic circuit composed of only a single electronic device, is configured as a part of the CMOS-LSI 10. As described above, a single-electron device logic circuit manufactured separately is mounted on a part of the CMOS-LSI 10 which is a base structure manufactured by the conventional technology. The single electronic device logic circuit portion formed up to the connection electrode is separated from the substrate by using the FIB to form the ultrafine structure 21.

  At this time, the single electronic device logic circuit portion is separated from the ultrafine functional device substrate 20 so that the side surface 21D of the ultrafine structure 21 extends from the substrate surface 21C on which the input / output terminal 21B is provided toward the bottom surface. That is, the side surface 21D of the ultrafine structure 21 is inclined. In order to incline the side surface 21D, it is only necessary to incline the ultrafine functional device substrate 20 at the time of separation. The well-focused focused ion beam used at this time is a Ga ion beam accelerated to about 30 kV and has a beam diameter of 5 to 30 nm. Further, the inclined side surface 21D becomes a part of the wiring path for the input / output terminal 21B.

  After that, as shown in FIG. 3, the ultrafine structure 21 is moved to the CMOS-LSI 10 which is the base structure, and is mounted at a predetermined position, that is, the mounting area 13 of the CMOS-LSI 11 as shown in FIG. Thereafter, the input / output terminal 21B, which is a connection electrode on the single electronic device circuit, and the connection electrode 13A on the corresponding base structure are wired using a tungsten film deposition function, which is a part of the FIB function. .

  As shown in FIG. 5, when connecting the input / output terminal 21 </ b> B and the connection electrode 13 </ b> A, the side surface 21 </ b> D of the ultrafine structure 21 is inclined when the metal wiring is formed by the tungsten film deposition function. That is, the inclined side surface 21D becomes a part of the wiring connection portion, and the step between the wiring connection portion and the CMOS-LSI 10 is eliminated, so that the film deposition for the metal wiring on the side surface 21D can be reliably performed.

  Thereby, the circuit on the base structure and the single electronic device circuit are electrically connected to operate as one functional device. The electrode wiring interconnecting the substrate structure and the ultrafine device used here is significantly smaller than the mounting electrode formed by the conventional method. For this reason, by connecting to the CMOS-LSI 10 via an appropriate input / output circuit, integration is possible without impairing the characteristics of a low power consumption device such as a single electronic device.

In the reference examples so far, an LSI having a relatively simple circuit configuration is exemplified as the base structure, but the present invention can also be applied to a more complicated and highly functional LSI system as shown in FIG. In FIG. 6, functional circuit blocks 31 to 33, an input / output circuit 34, and the like are formed in the CMOS-LSI 30. By appropriately designing the input / output circuit, not only the above-mentioned Si single-electron device circuit but also non-Si-based devices such as a carbon nanotube (CNT) device, a DNA device, a self-organizing device, etc. are brought onto the CMOS-LSI 30. As in FIGS. 1 to 5, the micro structure 35 can be mounted.

  In addition, as the base structure, it is apparent that the present invention can be applied to, for example, integration of an ultrafine device for measurement into a microchannel on a quartz substrate for biological information measurement. The point is that any combination is possible as long as a sufficiently high-functional fine structure is integrated on a base structure having a function that can be formed by a conventional technique to obtain a more effective function. Of course, it is also possible to integrate a plurality of ultrafine structure devices on one base structure.

In this reference example, tungsten (source gas W (CO) 6), which is the most widely used metal for electrode connection, is taken as an example. However, if a sufficiently low resistance value is obtained, other metals (for example, Pt or the like). In short, any conductive film can be used as long as it can be deposited in an arbitrary shape by a beam-induced reaction by FIB. Further, in this reference example, only metal wiring is mentioned. However, if an insulating structure for separation is required at the time of wiring, by using a gas species capable of depositing an insulating thin film, a beam-induced reaction by FIB is performed. Any shape of insulating structure can also be formed. If there is no restriction on the apparatus configuration, it is also possible to use a deposited film excited by an electron beam using an electron beam of an SEM (scanning electron microscope) for observation.

  When designating the position to perform processing (cutting / wiring), the SIM (secondary ion microscope) function that is standardly equipped in the FIB may be used. However, other microscopic techniques with less damage, for example, Needless to say, an SEM (scanning electron microscope) may be used in combination.

  The means for transferring the structure including the ultrafine device cut from the substrate onto the base structure is not particularly limited as long as the fine structure can be handled under a microscope (SIM or SEM). In general, a method of transferring using a needle-shaped movable rod having a sharp tip is known. When cutting the fine structure from the substrate, after fixing its one end to the tip of the movable rod, replace the substrate containing the fine structure and the base structure, and at a desired position on the base structure, It is only necessary to install the cut out fine structure, and the fine structure transfer rod can be transferred only by vertical movement. Of course, there is no problem even if movement in three dimensions is possible.

Reference example 2

In this reference example, the mounting of a Si single electronic device and a circuit on the measurement circuit board structure is taken as an example. As devices become smaller, it becomes difficult to measure the performance of a single test device. This is because various parasitic effects occur because the size of the measurement electrodes connected to the single device is larger than that of the target device.

In order to prevent parasitic effects, it is effective to connect a single device directly to a measurement circuit. There is no problem if the measurement circuit can be formed on the same process and the same substrate, but this is not possible, for example, in the case of a state-of-the-art device such as a single-electron device or a CNT device as mentioned in Reference Example 1. It is. For this reason, if a single device is cut out using FIB and installed and wired on a base structure in which a circuit for measurement is formed in advance, the characteristics can be measured.

  This technique can be applied to, for example, to extract a device at a specific failure location by FIB processing and measure it, and to elucidate the cause of the failure. If the size is within the range that can be handled by FIB processing, not only a single device but also a certain functional block unit can be measured. In short, it is only necessary that a desired location can be cut out, and this can be wired to the electrode on the substrate structure by the wiring function of the FIB.

7 and 8 show an example in which the present invention is applied to the characteristic analysis of the fine device. In this reference example, the measurement circuit block 41 and the external connection electrode 42 are formed in advance on the measurement circuit board structure 40. In the predetermined area 43 of the measurement circuit block 41, two sets of four connection electrodes are formed. That is, four connection electrodes 43A and four connection electrodes 43B are formed.

In this reference example, one Si single-electron device 51A is fabricated on an ultra-fine functional device substrate and wired to four connection electrodes 51B, and a single-electron device circuit 52A composed of a plurality of single-electron devices. The four connecting electrodes 52B are cut out by FIB processing.

The ultrafine structures 51 and 52 are cut out as follows. As shown in FIG. 9, FIB tilt processing (+60 degrees) is performed when a device created on the ultrafine functional device substrate 50 is cut out. That is, the ultrafine functional device substrate 50 is tilted with respect to the ion beam irradiation direction. Thus, by well focused ion beam from the A direction, the groove 50 ₁ is formed. The well-focused focused ion beam used at this time is a Ga ion beam accelerated to about 30 kV and has a beam diameter of 5 to 30 nm. Next, FIB tilt machining (−30 degrees) is performed. Thus, by well focused ion beam from the B direction, a groove 50 ₂ is formed. Furthermore, the fine structure is cut out from the substrate by performing FIB processing on both ends of the structure (the front side and the back side in FIG. 9). Immediately before the structure is completely separated from the substrate by processing, a part of the fine structure transfer mechanism is brought into contact with and fixed to a part of the structure. The Ga ion beam used in the FIB processing needs to be well focused so as not to damage the device on the ultrafine structure. In the case of general FIB processing, a protective film for preventing damage is deposited on the structure to be processed, so that some beam expansion is allowed, but in this reference example, ion beam damage affects device characteristics. Because there is a possibility, it is necessary to reduce as much as possible.

  Thereafter, the ultrafine structure 51 is mounted at a predetermined position, that is, the region 43 of the measurement circuit base structure 40. And the electrode on a base structure and the electrode of the single-electron device on the corresponding micro structure 51 are connected with the some metal wiring deposited using the beam excitation reaction of FIB.

  Further, similarly to the ultrafine structure 51, the ultrafine structure 52 including the single electronic device circuit is cut out by FIB processing, transferred to a predetermined position, that is, the region 43 of the measurement circuit base structure 40, and FIB wiring is formed. .

In this case, the cross-sectional shape of the way, very fine structure 51 shown in FIG. 10 is a wedge-shaped, are prepared the substrate surface 51 ₁ to the four connection electrodes 51B of ultrafine structures 51. The very fine structure 51 obtained by processing the wedge, measured by mounting the measuring circuit for base structure 40 in an inclined surface of the substrate 51 _1, as shown in FIG. 10, the electrode wiring connection portion of the microstructure 51 Since the step with the circuit board structure 40 is eliminated, when the FIB wiring 53A is formed using the tungsten film deposition function which is a part of the FIB function, the connection electrode 51B and the connection electrode 43A are not connected. An electrical connection can be made reliably. The same applies to the FIB wiring 53B between the connection electrode 52B and the connection electrode 43B.

In this reference example, an example in which a measurement circuit is formed on a base structure is described, but a base structure in which an appropriate electrode group that can be connected to an external measuring instrument is simply formed.

  The device to be measured need not have a metal electrode formed in advance as long as it can be electrically connected by an electrode formed of a metal that can be deposited by FIB. If, for example, the functions of the source, drain, and gate can be realized by the electrode formed in an arbitrary shape by the FIB deposited film, it is not necessary to prepare this in advance. Even in a situation where the wiring electrode to be measured is covered with an insulating film, there is no problem if the insulating film is removed by FIB processing and then the wiring is provided by the FIB deposited film to ensure electrical connection.

  In this embodiment, the case where the ultrafine device is a single electron device sensor on a probe for a scanning probe microscope (SPM) is taken as an example. A probe for a scanning probe microscope generally obtains various types of information by scanning the surface of an observation target with a single probe. If an ultrafine device having various measurement functions can be used in place of the single probe, the function is dramatically improved.

  FIG. 11 is a diagram showing an embodiment in which a separately prepared ultrafine device for measurement is mounted on the tip of the cantilever portion 61 of the probe 60 for SPM. The probe 60 is a four-wire SPM probe. Here, an example is shown in which a Si single-electron device is mounted as a highly sensitive charge sensor. An ultrafine structure 70 is provided at the tip of the probe 60.

The structure of the ultrafine structure 70 is shown in FIGS. FIG. 12 is a plan view showing the ultrafine structure of FIG. 13 is a cross-sectional view showing a partial cross section of FIG. 12, wherein (a) shows a cross section along line L1 in FIG. 12, and (b) shows a cross section along line L2 in FIG. A sensing Si single-electron device 71C is formed on an SOI substrate by an existing technology, and an appropriately patterned SOI-Si layer 71 ₁ that operates as a MOSFET on the SOI substrate (partly operates as a single-electron device). (Including the ultrafine wire structure) is thermally oxidized under appropriate conditions to form a single-electron device (see Reference 1 described above). In very fine structure 70, by patterning the SOI-Si layer 71 ₁ in a single electronic device part, it is a structure fitted with a sense for side gate 71D and the control side gate 71E.

  The sense Si single-electron device 71C, the sense side gate 71D, and the control side gate 71E are provided on the Si substrate 71A via the buried oxide film layer 71B. The sensing Si single-electron device 71C, the sensing side gate 71D, and the control side gate 71E are covered with a thermal oxide film 71F.

Since it is effective to use two types of gates for controlling the characteristics of the sensing single-electron device 71C, the substrate itself is used as a back gate through a buried oxide film using a substrate contact electrode. Therefore, in order to operate this device, a source electrode, a drain electrode, and two control gate electrodes (side gate and substrate contact) are required, and this electrode region is opposite to the sensing side gate probe electrode. It is formed on the side. The substrate including the Si single electronic device is processed by the same method as in Reference Example 2 to form the ultrafine structure 70. In this example, FIB tilt processing (+60 degrees) and FIB tilt processing (-45 degrees) are performed to form a wedge shape. Immediately before the separation from the substrate, after joining to the probe for movement, the substrate containing the single electron device is removed, and instead the probe 60 for the scanning probe microscope is introduced into the FIB apparatus.

In the cantilever portion 61 of the probe 60, four Al wirings 61A to 61D are formed in advance. After adjusting the position of the probe 60 for the scanning probe microscope and the single-electron device, the ultrafine structure 70 in which the single-electron device is formed is placed at a desired position at the tip of the cantilever 61. Thereafter, the silicon layer of the source / drain / side gate / substrate contact portion of the device is exposed by etching using FIB to form a contact region. Thus, the source electrode _{71 11,} and the drain electrode _{71 12,} a substrate contact _{71 13,} and the Si layer contact _{71 14} are formed.

Etching for contact formation for the source, drain, and side gate is sufficient if the thermal oxide film 71F on the Si layer can be removed. In the case of substrate contact formation, it is necessary to remove the buried oxide film 71B. After forming the contact region, that is, after forming the source electrode 71 ₁₁ , the drain electrode 71 ₁₂ , the substrate contact 71 ₁₃ , and the Si layer contact 71 ₁₄ , each electrode and the cantilever AI wirings 61A to 61D are deposited by FIB. Connect by 62A-62D.

  After attaching the probe prepared in this way to the scanning probe microscope, the device is operated by applying an appropriate voltage to the four electrodes. Various charge distributions can be measured.

  In this embodiment, as an example of the ultrafine device mounted on the probe tip, a single-electron device which is a kind of highly sensitive charge meter has been described. However, a device having other useful functions may be used. For example, various devices such as a four-probe probe capable of local resistance measurement or a plurality of ultrafine movable probes (nanomanipulators) can be mounted. By fabricating the scanning probe and the tip structure separately, the degree of freedom in the use of the tip structure that can be used is greatly increased, and various high-sensitivity functional devices can be used as sensors. It becomes.

  In addition, although a structure having only a simple wiring is cited as a probe that is a base structure, a cantilever part of a probe having a more complicated function such as a self-detection function (deflection can be detected by a piezoresistor) May be used.

  Further, the number of wirings arranged on the cantilever is not limited to four, and may be increased or decreased as necessary for the functional device mounted on the tip. In short, instead of a single simple probe that does not have a normal special function at the tip of the cantilever of a probe that can be realized with existing technology, a functional device having a plurality of separately manufactured electrodes is used in FIB processing technology. It only has to be mounted using.

  The present invention can be used in a field where very fine device structures are integrated, for example, in a fine semiconductor device. Further, it can be used in the field of inspecting a very fine device structure, for example, an inspection process of a fine semiconductor device. Furthermore, in the future, it can be used in the field where higher-performance devices can be realized by integrating ultrafine devices, for example, in the field of microelectronic machines such as scanning probe microscopes and microchannel application technology.

It is a perspective view which shows CMOS-LSI used for the reference example 1 of this invention. It is a perspective view explaining the ultrafine functional device used in Reference Example 1. It is a perspective view explaining mounting of the ultrafine structure by the reference example 1. FIG. It is a perspective view explaining mounting of the ultrafine structure by the reference example 1. FIG. It is a perspective view explaining the wiring formation by the reference example 1. FIG. 10 is a perspective view showing another CMOS-LSI according to Reference Example 1. FIG. 10 is a plan view for explaining characteristic analysis according to Reference Example 2. FIG. It is a perspective view which shows a mode that the part of the area | region of FIG. 7 was expanded. It is explanatory drawing explaining the cutting-out of the ultrafine structure by the reference example 2. FIG. It is explanatory drawing explaining the metal wiring by the reference example 2. FIG. It is a perspective view of a probe for a scanning probe microscope according to the embodiment. It is a top view which shows the ultrafine structure of FIG. FIGS. 13A and 12B are cross-sectional views showing a partial cross section of FIG. 12, in which FIG. 12A shows a cross section along line L1 in FIG. 12, and FIG. 13B shows a cross section along line L2 in FIG. It is explanatory drawing for demonstrating a prior art.

10, 30 CMOS-LSI
DESCRIPTION OF SYMBOLS 11, 31-33 Functional circuit block 12 Electrode 13 Mounting area | region 13A Connection electrode 20 Ultrafine functional device board | substrate 21, 35 Ultrafine structure 21A Ultrafine functional device 21B Input / output terminal 21C Substrate surface 21D Side 34 Input / output circuit 40 Measurement Circuit board structure 41 Measurement circuit block 42 External connection electrodes 43A, 43B Connection electrode 50 Ultrafine functional device substrate 50 ₁ groove 51, 52 Ultrafine structure 51 ₁ substrate surface 51A Si single electronic device 51B connection electrode 60 Probe 61 Cantilever part 61A-61D Al wiring 62A-62D W electrode 70 Extremely fine structure 71 ₁ SOI-Si layer 71 ₁₁ Source electrode 71 ₁₂ Drain electrode 71 ₁₃ Substrate contact 71 ₁₄ Si layer contact 71A Substrate 71B Embedded oxide layer 71C Si single electronic device 71 for sense Side gate 71F thermal oxide film for the sense for a side gate 71E control

Claims (11)

A functional device formed on a substrate by a first process and having a plurality of input / output electrodes separated from the substrate;
A substrate structure having a region on which the functional structure is mounted and a plurality of input / output electrodes connected to the plurality of input / output electrodes, and manufactured by a second process;
A wiring formed by beam-excited reaction deposition that connects the plurality of input / output electrodes of the base structure and the corresponding input / output electrodes of the functional structure;
The functional structure has a shape in which a step in the route of the wiring is suppressed,
The base structure is a cantilever of the scanning probe microscope probe, integrated electronic device according to claim that you have the functional structure to the tip of the cantilever portion is mounted.   The integrated electronic device according to claim 1, wherein the functional structure has a shape in which a side portion is inclined.   2. The integrated electronic device according to claim 1, wherein the functional structure has an inclined substrate surface on which the functional device and the input / output electrode are formed, and has a wedge-shaped cross section.   2. The integrated electronic device according to claim 1, wherein the beam excitation reactive deposition is one of focused ion beam deposition and electron beam excitation deposition. The integrated electronic device according to claim 1, wherein the functional structure is a charge sensor. Integrated electronic device according to any one of claims 1 to 5, characterized in that the functional structure is a single-electron device. A manufacturing method of an integrated electronic device for manufacturing the integrated electronic device according to any one of claims 1 to 6
A first step of cutting out a functional device having a plurality of input / output electrodes produced on a substrate by a first process from the substrate as a functional structure under a microscope;
A second step of mounting the functional structure on a base structure having a plurality of input / output electrodes fabricated by a second process;
The functional structure is fixed to the base structure under a microscope, and the input / output electrodes of the base structure and the input / output electrodes of the functional structure are formed by beam excitation reaction deposition. A third step of connecting by the connected wiring,
When the functional structure is separated from the base in the first step, the base is formed so that a step in the path of the wiring formed in the third step is suppressed. A method of manufacturing an integrated electronic device, characterized in that it is separated from the device. 8. The method of manufacturing an integrated electronic device according to claim 7 , wherein, in the first step, the functional device is separated from the substrate in a shape in which a side portion is inclined. 8. The integrated electron according to claim 7 , wherein, in the first step, the cross-sectional shape is wedge-shaped so that the substrate surface on which the input / output electrodes of the functional device are formed is inclined, and is separated from the substrate. Device manufacturing method. 10. The method for manufacturing an integrated electronic device according to claim 7 , wherein focused ion beam processing is used for cutting out and separating the functional device in the first step. 11. In the third step, the functional device is fixed or electrode-connected to the base structure using a deposited film formed by one of focused ion beam deposition and electron beam excitation deposition. The method for manufacturing an integrated electronic device according to claim 7 .

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