JP2007128433A - Rf powder and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide RF powder characterized so as to be used as powder (powdery material) constituted of large amounts of particles in collective configurations, wherein each of the large amounts of particles consisting of powder is used as an element which is more compact in size than a current IC tag, and which is provided with a function substantially equivalent to that of the IC tag chip, and as its use mode, it is used not as any individual element but as powder, and its dealing is made simple, and manufacturing costs are made extremely inexpensive in respect of the unit price of each particle, and its practicality is made extremely high and to provide a manufacturing method thereof. <P>SOLUTION: RF powder 11 is used in the mode of powder, and each particle 11a of powder is configured of an integrated circuit 13 formed on a substrate 12, an insulating layer 14 formed on the integrated circuit and an antenna element 15 formed on the insulating layer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to RF powder and a method for producing the same, and more particularly to an RF powder that can be used as powder, contained in paper, etc., and capable of reading information by a high-frequency electromagnetic field (wireless) applied from the outside, and a method for producing the same.

  At present, IC tags are considered as products at the entrance of the ubiquitous era. As RF-ID (ultra-small wireless recognition), name tags, watermelon cards, FeRAM cards and the like have been developed for some time. Many people expect that the market for IC tags will surely grow larger in the future. However, the market is still not growing as expected. This is because there are issues other than technology that must be solved socially, such as cost, security, and confidentiality issues.

  The cost of the IC tag can be reduced by reducing the size of the IC tag chip. This is because if the size of the IC tag chip is reduced, the number of IC tag chips obtained from one wafer can be increased. At present, a 0.4 mm square IC tag chip has been developed. This IC tag chip can read 128-bit memory data in the chip with a microwave of 2.45 GHz (see, for example, Non-Patent Document 1).

  However, when manufacturing an ultra-small IC tag chip from a single wafer, the conventional manufacturing method has the following problems.

  A conventional IC tag chip manufacturing method is described, for example, in the section of the prior art in Patent Document 1. According to this manufacturing method, a back grinding process is performed on a wafer having an IC formed on the front surface, and the back surface of the wafer is polished to reduce the thickness of the wafer. Thereafter, a dicing process is performed on the wafer to separate a large number of IC tag chips having a predetermined shape. In this dicing process, the wafer is cut by a dicing saw and separated into a number of IC tag chips. In the separation method in which a wafer is cut along a dicing line with a dicing saw, the wafer portion such as a substantial area area used for cutting and an area area affected by the cutting process may be used for manufacturing an IC tag chip. Can not. Further, as the IC tag chip becomes smaller, the number of dicing lines further increases. As a result, the ratio of the unusable area to the entire area of the wafer increases, and the wafer cannot be used effectively. That is, the number of IC tag chips that can be cut from one wafer is reduced.

Therefore, Patent Document 1 proposes a new semiconductor element isolation method to solve the above problem. According to the semiconductor element separation method of Patent Document 1, a half cut is formed by etching a separation position for separating a semiconductor element from the surface side of the wafer on which a circuit is formed, and a tape material is pasted on the surface side of the wafer. After that, the back side of the wafer is mechanically polished by a predetermined thickness so that it does not communicate with the half-cut on the front side, and etching or chemical mechanical polishing is performed from the back side of the wafer, and the wafer is separated into individual semiconductors. Separate into elements. As described above, since the half cut is formed by etching, the width of the half cut can be narrowed and the portion to be scraped off can be reduced, and the number of semiconductor elements that can be taken from one wafer can be increased.
JP 2003-179005 A Mitsuo Usami, “Ultra-miniature wireless IC tag chip“ Muchip ””, Applied Physics, Vol. 73, no. 9, 2004, p. 1179-p. 1183

  The IC tag chip disclosed in Non-Patent Document 1 is inherently a semiconductor element handled individually. However, since the IC tag chip is typically an ultra-small semiconductor element of about 0.4 mm, it is not easy to handle each one individually in actual handling. Furthermore, it is not so cheap in terms of cost.

  Further, according to the semiconductor element isolation method proposed by Patent Document 1, when manufacturing RF powder composed of a large amount of ultra-small semiconductor elements of 0.4 mm square or less, a wafer is separated to produce a large amount of semiconductor elements. After that, it is very difficult to uniformly apply a protective film to each of extremely fine semiconductor elements that are particles.

  The “RF powder” means that a large amount of particles forming a powder (powder or powder) are transmitted with a signal (information) from an external reader / writer device via radio (high frequency electromagnetic field). ) Means an electric circuit element that performs transmission and reception, and is used as a powder whose normal usage is a collective form.

  In view of the above problems, the object of the present invention is to be used as a powder (powder) consisting of a large amount of particles and taking a collective form, and each of the large amount of particles constituting the powder is a current IC. Compared to tag chips, it is smaller in size and used as an element having substantially the same function as an IC tag chip, and its usage is used as a powder rather than as an individual element, making it easy to handle Therefore, an object of the present invention is to provide an RF powder having a very low production cost in terms of the unit price of each particle and having a very high practicality, and a manufacturing method thereof.

  In order to achieve the above object, the RF powder and the manufacturing method thereof according to the present invention are configured as follows.

  The first RF powder (corresponding to claim 1) is used in the form of powder, and each particle of the powder is an integrated circuit formed on the substrate, an insulating layer formed on the integrated circuit, and an insulating layer on the insulating layer. The antenna element is formed.

  The above RF powder is not handled by the concept of an individual IC chip, but is always used and managed as a powder (powdered body), and a plurality of particles are used at the same time. Each of the plurality of particles includes an integrated circuit element and has a function of transmitting / receiving required information to / from an external reader / writer via a high-frequency electromagnetic field.

  The second RF powder (corresponding to claim 2) is used in the form of a powder, and each particle of the powder is formed on a substrate and configured to have a resonator that is sensitive to an external electromagnetic field. In this configuration, each particle of the RF powder does not have an integrated circuit element, and has a function of transmitting and receiving required information by a resonator that is sensitive to a high-frequency electromagnetic field from the outside.

  A third RF powder (corresponding to claim 3) is characterized in that, in the above structure, the resonator is an antenna element formed on a substrate or an antenna element formed on an insulating layer on the substrate. To do.

  A fourth RF powder (corresponding to claim 4) is characterized in that, in the above RF powder, each particle of the powder is mixed and used in a medium without inspection.

  Further, a fifth RF powder (corresponding to claim 5) is characterized in that, in the RF powder, each particle of the powder is stored and managed in a container in a powder state.

  In the sixth RF powder (corresponding to claim 5), in each of the RF powders described above, preferably, the size of the rectangular plane including the longest side of the particle is 0.30 mm square or less and 0.05 mm square or more. Features.

  The seventh RF powder (corresponding to claim 7) is preferably characterized in that, in the third RF powder, the size of the rectangular plane including the longest side of the particle is 0.15 mm square.

  A first RF powder manufacturing method (corresponding to claim 8) includes an integrated circuit in which one particle is formed on a substrate, an insulating layer formed on the integrated circuit, and an antenna formed on the insulating layer. A process for producing a large amount of integrated circuit elements with antennas to be particles on a wafer by using parallel light or X-ray exposure. A gas dicing step of forming a kerf at a position for separating the integrated circuit element with the antenna on the surface of the wafer on which the antenna element is formed, and a protective film that covers the periphery of the integrated circuit element with the antenna with a protective film Forming step, reinforcing step of attaching a reinforcing plate with an adhesive to the front surface side of the wafer on which the protective film is formed, polishing step of polishing the back surface of the wafer to the kerf, and removing the adhesive A method and a separation step of separating the antenna with the integrated circuit device to remove the plate.

  In the second RF powder manufacturing method (corresponding to claim 9), one particle has a resonance circuit that is formed on a substrate and is sensitive to an external electromagnetic field, and the RF powder is composed of a large amount of the particle. Manufacturing a large number of circuit elements to be particles on the wafer using parallel light or X-ray exposure, and forming circuit elements on the surface of the wafer on the side where the resonance circuit is formed. Gas dicing process for forming a kerf at a position for separation, protective film forming process for covering the periphery of the circuit element with a protective film, and strengthening by attaching a reinforcing plate with an adhesive to the surface side of the wafer on which the protective film is formed And a separation step of separating the circuit element by removing the adhesive and removing the reinforcing plate.

  The third RF powder manufacturing method (corresponding to claim 10) is preferably characterized in that, in each of the above manufacturing methods, the adhesive is a material that is soluble in an organic solvent. This adhesive has an adhesive function and a solidifying function. Examples of the material soluble in the organic solvent include paraffin, wax, wax and the like.

  The fourth RF powder manufacturing method (corresponding to claim 11) is preferably characterized in that, in each of the above manufacturing methods, the reinforcing plate is a ceramic plate.

  According to the present invention, since it is not used as one individual IC tag chip or the like but as RF powder, it is easy to handle and can be manufactured at low cost. Further, according to the present invention, the protective film forming step of covering the periphery of the particles with the protective film is provided before the particles are separated, so that the protective film can be uniformly applied to each particle.

  In order to separate each particle of RF powder from the wafer, when polishing the backside of the wafer as a pre-treatment, the inside of the separation groove formed on the wafer surface is coated with a ceramic plate by applying paraffin or the like to the wafer surface. Since paraffin or the like is filled in and solidified, polishing can be performed by mechanical polishing until the bottom of the kerf is reached without causing cracks or cracks. For this reason, the whole manufacturing process of RF powder is simplified and manufacturing cost can be reduced.

  DESCRIPTION OF EMBODIMENTS Preferred embodiments (examples) of the present invention will be described below with reference to the accompanying drawings.

  1 to 6 show a first embodiment of the RF powder according to the present invention. FIG. 1 shows the manner in which RF powder is used, stored and managed. FIG. 1 shows a state in which RF powder 11 is contained in a container 1 such as a bottle. The RF powder 11 according to the present invention is always in the form of being used as a powder (powder or powder).

  FIG. 2 is a diagram showing a plurality of particles 11a extracted from the container 1 and placed on a sheet-like member 2 such as rectangular paper, and an enlarged view of each particle 11a. In FIG. 2, the size of each particle 11a forming the RF powder 11 is exaggerated. The thickness of the sheet-like member 2 is not shown exaggerated. Hereinafter, the “particles 11a” will be referred to as “powder particles 11a”.

  FIG. 3 shows a longitudinal section of a main part of one of the plurality of powder particles 11a shown in FIG. In FIG. 3, the powder particles 11a of the RF powder 11 are shown with an exaggerated thickness. Regarding the plurality of rectangular planes on the outer surface, the powder particle 11a has a rectangular plane including the longest side having a size of 0.30 mm square or less and 0.05 mm square or more, more preferably 0.15 mm square. It has a three-dimensional shape. In the powder particle 11a of this embodiment, the front side L in FIG. 3 is 0.15 mm (150 μm).

  Each of a large number of powder particles 11 a forming the RF powder 11 is formed on an integrated circuit (IC) 13 having a memory function such as FeRAM formed on a substrate 12 such as silicon and the integrated circuit 13. In addition, an insulating layer 14 having a thickness of about 30 μm and an antenna element 15 sensitive to an electromagnetic field of a specific frequency (for example, 2.45 GHz) formed on the insulating layer 14 are provided. In FIG. 3, as an example of an electric circuit element, transistors 16 and 17 constituting the integrated circuit 13, wiring 18 connected to the transistors 16 and 17, and wiring 19 connecting the antenna element 15 and the integrated circuit 13 are shown. . The wiring 19 is embedded in the insulator 14.

  FIG. 4 shows an example of the circuit configuration of the integrated circuit 13 provided in each powder particle 11 a of the RF powder 11. The integrated circuit 13 includes, for example, a rectifier circuit 20, a voltage suppressor 21, an initial setting circuit 22, a clock circuit 23, a control register 24, a decoder 25, and a memory 26. These circuit elements have the following functions.

  The rectifier circuit 20 has a function of rectifying high-frequency electromagnetic waves coming from the outside into a DC power supply voltage. For example, an electromagnetic wave of 2.45 GHz introduced through the antenna 15 and the antenna terminal 27 is converted by the rectifier circuit 20 into a voltage for operating an internal analog circuit or digital circuit. When the powder particle 11a of the RF powder 11 approaches the reader / writer 32 (see FIG. 5) and receives excessive electromagnetic energy from the reader / writer 32, the voltage suppressor 21 generates an excessive voltage. This voltage is suppressed and the semiconductor element in the integrated circuit 13 is prevented from being destroyed. The initial setting circuit 22 controls the start and end of the circuit operation, and the clock circuit 23 demodulates the clock waveform. The memory 26 is, for example, an FeRAM that stores an identification number. The contents of the memory 26 are selected by the control register 24 and the decoder 25 and transmitted to the reader / writer 32.

  Next, an actual usage example of the RF powder 11 according to the first embodiment will be described with reference to FIGS. 5 and 6.

  A considerable number of powder particles 11a in the RF powder 11 are included in the sheet member 30 which is a medium such as paper. In FIG. 5, the thickness of the sheet member 30 is exaggerated and enlarged. When it is included in the sheet member 30 such as a banknote, for example, an aqueous solution (ink, paint, etc.) containing an adhesive fixing agent including the RF powder 11 is soaked into the sheet member 30 with a dropper or the like. Accordingly, the RF powder 11 can be attached to the surface of the sheet member 30 or can be soaked into the sheet member 30. At this time, each powder particle 11a is impregnated with no inspection. That is, it is not necessary to specifically test whether each powder particle 11a is normal or abnormal. FIG. 5 shows a state in which a plurality of powder particles 11 a of the RF powder 11 are soaked and arranged inside the sheet member 30. When the powder particles 11a are mixed into a medium such as paper, the powder particles 11a may be mixed at the stage of manufacturing the medium such as paper.

  The sheet member 30 containing the plurality of powder particles 11a of the RF powder 11 is scanned by a reader / writer 32 connected to a computer 31 to read information contained in each of the plurality of powder particles 11a. The computer 31 includes a display device 31a, a main body 31b, a keyboard 31c, and the like.

  The reader / writer 32 has a reading terminal 33 (see FIG. 6), and is provided from each powder particle 11a by using the high frequency electromagnetic wave (RF) in a specific frequency band including 2.45 GHz. Read information. The frequencies used in each of the plurality of powder particles 11a are different, for example, 1.9 GHz, 2 GHz, 2.50 GHz, and 2.54 GHz. Accordingly, the reader / writer 32 is configured to read electromagnetic waves in a frequency band of, for example, 1.9 to 2.54 GHz as the specific frequency band at an appropriate timing. Since the reader / writer 32 reads information from each of the plurality of powder particles 11a in the sheet member 30 via the reading terminal 33, the reader / writer 32 scans in a certain direction along the surface of the sheet member 30 and transmits and receives the information. The frequency is changed within a specific frequency band for the frequency to be used.

  FIG. 6 shows a state in which a signal (information) is transmitted and received based on a high-frequency electromagnetic wave given from the reader / writer 32 at a place where one certain powder particle 11 a included in the RF powder 11 is present. It is assumed that the reading terminal 33 provided on the lower surface of the reader / writer 32 performs scanning operation and is positioned above the powder particles 11 a of the RF powder 11. In this case, the reading terminal 33 radiates high frequency electromagnetic waves of several different frequencies, and when the electromagnetic waves of the frequency to which the powder particles 11a are sensitive are emitted (indicated by arrows 34 in FIG. 6), the powder particles 11a are The high frequency electromagnetic wave is received, the integrated circuit 13 is operated based on the energy, information from the memory 26 is taken out and radiated as a high frequency electromagnetic wave (indicated by an arrow 35 in FIG. 6). The electromagnetic waves emitted from the powder particles 11 a are received by the reading terminal 33 of the reader / writer 32. The reading terminal 33 of the reader / writer 32 sends the information received from the powder particles 11a to the computer 31, and the information provided from the powder particles 11a is stored in the memory of the computer 31 where the powder particles 11a are present. Is done.

  When the reader / writer 32 scans the inside and the entire surface of the sheet member 30 shown in FIG. 5, the RF powder 11 (multiple powder particles 11 a) existing in the entire scanning region of the sheet member 30. The information written in each is read and stored in the memory of the computer 31. Information stored in the memory of the computer 31 is displayed on the display device 31a as necessary.

  By making the RF powder 11 into a banknote, for example, or by making the RF powder 11 into an important document such as an official document, a license, an insurance card, or another important card by the above method, the banknote The RF powder 11 can be used for forgery discrimination, authentication of important documents, and the like. At this time, it is not used as a single IC tag chip, but is used as a powder (powder) that collectively uses a plurality or a large number of powder particles 11a, so that handling is easy.

  Next, with reference to FIG. 7 and FIG. 8, the manufacturing method of the said RF powder 11 which concerns on 1st Embodiment is demonstrated.

  FIG. 7 shows an overall process for manufacturing the RF powder 11, and FIG. 8 shows a longitudinal sectional structure of a wafer or powder particles 11a corresponding to each process.

  The manufacturing method of the RF powder 11 includes an element forming process (step S11), a resist pattern forming process (step S12), a gas dicing process (step S13), a protective film forming process (step S14), and a ceramic plate attaching process. (Step S15), a polishing step (Step S16), and a separation step (Step S17).

  Each of said process S11-S17 is outlined. The element formation step S11 is a step for manufacturing an extremely large number (large amount) of integrated circuit elements with antennas (39) on a wafer. The resist pattern forming step S12 is a step for forming a resist pattern on the wafer surface on which a large number of antenna integrated circuit elements are formed. The gas dicing step S13 is a step for forming a kerf using gas. The protective film forming step S14 is a step for forming a protective film for each integrated circuit element with an antenna. The ceramic sticking step S15 is a step for sticking a reinforcing plate such as a ceramic plate to the front side of the wafer with an adhesive that is soluble in an organic solvent such as paraffin, wax, or wax. The polishing step S16 is a step of polishing the back surface of the wafer until the bottom of the kerf is reached. The separation step S17 is a step for dissolving the integrated circuit element with an antenna, that is, the powder particles 11a, by dissolving an adhesive such as paraffin and making a large amount of powder particles 11a. Below, each said process is demonstrated in more detail.

  In the element formation step S11 described above, a very large number (large amount) of integrated circuits are formed on the surface of a wafer made of silicon or the like using a surface area excluding dicing lines, and the wafer on which the integrated circuits are formed. An insulating film (oxide film or the like) is formed on the surface with a thickness of about 30 μm, and an antenna element made of an inductor or the like is further formed on the insulating film. The antenna element is formed corresponding to each integrated circuit, and the corresponding integrated circuit and the antenna element are electrically connected by a buried wiring formed inside the insulator. The above-described integrated circuit element with an antenna is a semiconductor device composed of a set of integrated circuits, a set of corresponding antenna elements, wiring, and the like. In FIG. 8, an integrated circuit element with an antenna is indicated by reference numeral 39. As an exposure technique used to make a large number of ultra-small integrated circuits on the surface of a wafer and to make an antenna element on an insulator having a thickness of 30 μm deposited on the wafer surface, generally, A parallel light exposure technique, more preferably an X-ray exposure technique is used. When the insulating film is formed with a thickness of 30 μm, the surface of the insulating film is uneven, and transfer is impossible with a normal reduced projection light exposure technique having a focal depth, but an exposure technique for parallel rays (X-rays). By using this, it becomes possible to accurately transfer the mask pattern for forming the antenna element to the resist. Thereby, an antenna element can be made accurately. The antenna element is made of a copper material (copper plating). Further, the embedded wiring formed inside the insulator is also made of a copper material.

  The number of integrated circuits with antennas 39 formed on the wafer is, for example, 3 million for a 300 mm wafer and 1.4 million for a 200 mm wafer.

  Next, a resist mask pattern forming step S12 is performed (FIG. 8A). In the region near the surface of the wafer 40 shown in FIG. 8A, a large number of the integrated circuits are formed by the element formation step S11. Further, on the insulating film on the surface of the wafer 40, each integrated circuit is formed. Corresponding antenna elements are formed. A dicing line having a width of less than 50 μm, preferably in the range of about 10 μm to about 30 μm, is formed by lithography on the wafer 40 on which a large number of integrated circuits and antenna elements are formed by the element forming step S11. A resist mask pattern 42 from which 41 is removed is formed. In FIG. 8A, each of the plurality of resist mask patterns 42 corresponds to a set of integrated circuits, that is, the integrated circuit element 39 with an antenna described above.

  FIG. 8B shows a result of the gas dicing step S13 performed on the wafer 40. FIG. According to the gas dicing step S13, a portion of the dicing line 41 set based on the resist mask pattern 42 is deeply etched at a depth of 50 to 100 μm by plasma etching or the like on the surface of the wafer 40. The gas dicing step S13 is not performed for cutting / separating the wafer 40 but for forming the groove 40a to a depth of, for example, about twice or more of the long side of the integrated circuit element 39 with the antenna. This groove 40a will be referred to as a “cut groove”. As shown in FIG. 8B, the gas dicing step S13 forms a large number of cut grooves 40a for separating the integrated circuit element 39 with the antenna in a later step on the wafer 40 in a rectangular mesh shape. Become.

  In the subsequent protective film formation step S14, a protective film 43 such as a silicon nitride film (SiN) is formed with a required thickness on the surface side portion of the wafer 40 from which the resist mask pattern 42 has been removed, for example, by plasma CVD. ((C) of FIG. 8). The protective film 43 is formed up to the inner surface of the kerf 40a. In FIG. 8, the step of removing the resist pattern 42 located in the previous stage of the protective film forming step S14 is omitted.

  Further, in the subsequent ceramic plate pasting step S15, for example, paraffin 44 that acts as an adhesive / solidifying agent is applied to the wafer surface (FIG. 8D), and the wafer 40 is pasted on the ceramic plate 45 having the required strength. It is attached ((e) of FIG. 8). As a desirable state, the paraffin 44 is filled in the entire inside of the kerf 40a, and the paraffin 44 is embedded in all the kerfs 40a. The paraffin 44 solidifies after cooling. In place of the paraffin 44, an adhesive / solidifying material that can be dissolved in an organic solvent can be used.

  In the next polishing step S16, the back surface 46 side of the wafer 40 is polished. In this polishing step S16, the back surface 46 of the wafer 40 reaches the bottom 47 of the kerf 40a formed on the front surface and is polished until the paraffin 44 in the bottom 47 is exposed (FIG. 8). (F)). In this backside polishing, mechanical polishing is usually used. The polishing process can be completed simply by performing mechanical polishing. The reason is that even if the bottom of the kerf 40a is polished, the solidified paraffin 44 is embedded in the kerf 40a, so that problems such as cracks and cracks do not occur. The backside polishing is not limited to mechanical polishing, and other etching, chemical mechanical polishing, and the like can be used, and it is needless to say that these various types of polishing can be combined.

  In the final separation step S17, the temperature of the paraffin 44 is increased to dissolve the chemical. When the paraffin 44 is dissolved, the ceramic plate 45 is removed, and the portion of the wafer 40 where the integrated circuit element 39 with the antenna is formed is separated into the powder particles 11a described above ((g) in FIG. 8). In this way, a large amount of powder particles 11a is produced from one wafer 40. Each powder particle 11 a has an integrated circuit element 39 with an antenna composed of an integrated circuit and an antenna element, and this integrated circuit element 39 with an antenna is protected by a protective film 43.

  As described above, the RF powder 11 according to the first embodiment described with reference to FIGS. 1 to 6 can be manufactured. According to this manufacturing method, since the protective film forming step S14 for covering the periphery of the integrated circuit element with antenna 39 in the powder particles 11a with the protective film 43 is provided before the powder particles 11a are separated, the powder particles 11a are provided. The protective film 43 can be uniformly applied to the integrated circuit element 39 with antenna. In this embodiment, the mask pattern forming method using resist is exemplified, but the same effect can be obtained by a mask pattern forming method using photosensitive polyimide or the like.

  Next, a second embodiment of the RF powder according to the present invention will be described with reference to FIGS.

  9 to 11, the same elements as those described in the first embodiment are denoted by the same reference numerals.

  FIG. 9 is an external perspective view showing a part of one powder particle 50 in cross section. The powder particles 50 are stored and managed in the container 1 as shown in FIG. 1 and are used in the usage mode shown in FIG. The size of the powder particles 50 is the same as that of the aforementioned powder particles 11a. The powder particle 50 has a resonator 52 formed on a substrate 51 such as silicon. The resonator 52 is formed of a capacitive element and an inductive element using an antenna and an insulator. Reference numeral 51a in the figure is a protective film such as SiN. The resonator 52 has a function sensitive to a high frequency electromagnetic field of a specific frequency, for example, 2.45 GHz. When the reader / writer is formed of an inductance element, the sensitive frequency changes due to mutual inductance depending on the degree of proximity. The reader / writer is designed with this in mind. When the sensitive frequency is fixed to a specific value, it can be designed to be actively fixed by an integrated circuit.

  An actual usage example of the RF powder according to the second embodiment will be described with reference to FIGS. 10 and 11. FIG. 10 is a view similar to FIG. 5 described above, and FIG. 11 is a view similar to FIG. 6 described above. A large number of powder particles 50 of the RF powder according to the present embodiment are attached to the surface of the sheet member 30 or embedded therein as in the first embodiment described above.

  A sheet member 30 including a large number of powder particles 50 is read by a reader / writer 53 connected to a computer 31. The reader / writer 53 has an electromagnetic wave radiation part 53a and an electromagnetic wave detection part 53b. The electromagnetic wave radiation portion 53 a is disposed on the upper side of the sheet member 30, and the electromagnetic wave detection portion 53 b is disposed on the lower side of the sheet member 30. The electromagnetic wave radiation part 53a and the electromagnetic wave detection part 53b are located at the same position in the vertical direction with the sheet member 30 interposed therebetween, and are moved in a predetermined direction with the same positional relation. In the reader / writer 53, the electromagnetic wave radiation unit 53a further includes an electromagnetic wave radiation terminal 54a, and the electromagnetic wave detection unit 53b includes an electromagnetic wave detection terminal 54b. The electromagnetic wave radiation terminal 54 a of the electromagnetic wave radiation part 53 a and the electromagnetic wave detection terminal 54 b of the electromagnetic wave detection part 53 b move in synchronization along the front and back surfaces of the sheet member 30 to scan the sheet member 30. The reader / writer 53 performs a detection operation using the frequencies included in the specific frequency band described above at each scanning position.

  FIG. 11 shows the coupling relationship of the high-frequency electromagnetic field with the reader / writer 53 at the location where a certain powder particle 50 included in the RF powder according to this embodiment is present. When the electromagnetic wave radiation terminal 54a of the electromagnetic wave radiation part 53a performs a scanning operation and reaches the upper position of the powder particle 50, the frequency is changed to radiate a high frequency electromagnetic field, and an electromagnetic field having a frequency to which the powder particle 50 is sensitive is radiated. When this is done, the resonator 52 resonates in the powder particles 50, and the electromagnetic energy (arrow 55) is absorbed by the powder particles 50. Further, in the powder particle 50, the electromagnetic wave (arrow 56) whose intensity is reduced by the electromagnetic wave absorbing action is detected by the electromagnetic wave detection terminal 54b of the electromagnetic wave detection unit 53b. Information related to the detection value detected by the electromagnetic wave detection unit 53b is sent to the computer 31, and the electromagnetic wave absorption data at the scanning position is stored in the memory.

  The reader / writer 53 scans over the entire sheet member 30 shown in FIG. 10, whereby data relating to the amount of electromagnetic absorption by the RF powder (a large number of powder particles 50) in the entire area of the sheet member 30 is obtained by the computer 31. Is remembered. Information stored in the memory of the computer 31 is displayed on the display device 31a as necessary.

  According to the RF powder according to the second embodiment, it can be used for counterfeit discrimination of banknotes, authentication of important documents, and the like, similarly to the RF powder according to the first embodiment described above. In this case, it is easy to handle because it is used as a powder.

  The RF powder manufacturing method according to the second embodiment is different only in that a resonator is manufactured instead of manufacturing an integrated circuit element in the element formation step S11 in the RF powder 11 manufacturing method according to the first embodiment described above. The other steps are the same as those in the above-described embodiment, and thus description thereof is omitted.

  The configurations, shapes, sizes, and arrangement relationships described in the above embodiments are merely shown to the extent that the present invention can be understood and implemented, and the numerical values and the compositions (materials) of the respective configurations are as follows. It is only an example. Therefore, the present invention is not limited to the described embodiments, and can be variously modified without departing from the scope of the technical idea shown in the claims.

  The RF powder of the present invention is used as a powder element as an information recording medium or the like for use in document authentication or discrimination of counterfeit bills.

It is a figure which shows the aspect of use / management of RF powder which concerns on the 1st Embodiment of this invention. It is a figure which takes out some powder particles from RF powder concerning a 1st embodiment, exaggerates, and shows it expanded. It is a three-dimensional view showing a main part of one powder particle of the RF powder according to the first embodiment in cross section. It is a block diagram which shows the circuit structural example of the integrated circuit contained in one powder particle of RF powder which concerns on 1st Embodiment. It is an apparatus block diagram explaining the actual use application example of RF powder which concerns on 1st Embodiment. It is a figure which shows the transmission / reception relationship of the high frequency electromagnetic wave with the reader / writer in the presence location of one powder particle. It is a flowchart which shows the process of the manufacturing method of RF powder which concerns on 1st Embodiment of this invention. It is a structure sectional view of a wafer and powder particles corresponding to each process of a manufacturing method of RF powder concerning a 1st embodiment of the present invention. It is a perspective view which shows a part of one powder particle of RF powder concerning the 2nd Embodiment of this invention as a cross section. It is a figure explaining the actual use application example of RF powder concerning a 2nd embodiment. It is a figure which shows the transmission / reception relationship of the high frequency electromagnetic wave with the reader / writer in the location where one powder particle in 2nd Embodiment exists.

Explanation of symbols

1 Container 11 RF Powder 11a Powder Particle 12 Substrate 13 Integrated Circuit (IC)
DESCRIPTION OF SYMBOLS 14 Insulating layer 15 Antenna element 16, 17 Transistor 18, 19 Wiring 30 Sheet member 32 Reader / writer 39 Integrated circuit element with antenna 40 Substrate 40a Cut groove 43 Protective film 44 Paraffin 45 Ceramic plate

Claims (11)

  Each powder particle has an integrated circuit formed on a substrate, an insulating layer formed on the integrated circuit, and an antenna element formed on the insulating layer. RF powder.   An RF powder, wherein the powder is used in the form of a powder, and each particle of the powder has a resonator formed on a substrate and sensitive to an external electromagnetic field.   The RF powder according to claim 2, wherein the resonator is an antenna element formed on the substrate or an antenna element formed on an insulating layer on the substrate.   The RF powder according to any one of claims 1 to 3, wherein each particle of the powder is mixed and used in a medium without inspection.   The RF powder according to any one of claims 1 to 3, wherein each particle of the powder is stored and managed in a container in the state of the powder.   The RF powder according to claim 1 or 2, wherein a size of a rectangular plane including the longest side of the particles is 0.30 mm square or less and 0.05 mm square or more.   The RF powder according to claim 6, wherein the rectangular plane including the longest side of the particle has a size of 0.15 mm square. An integrated circuit in which one particle is formed on a substrate, an insulating layer formed on the integrated circuit, and an antenna element formed on the insulating layer, and manufacturing RF powder composed of a large amount of the particles A method,
Producing a large number of integrated circuit elements with antennas to be the particles on the wafer using exposure by parallel rays or X-rays;
A gas dicing step of forming a kerf at a position for separating the integrated circuit element with the antenna on the surface of the wafer on which the antenna element is formed;
A protective film forming step of covering the periphery of the integrated circuit element with the antenna with a protective film;
A reinforcing step of attaching a reinforcing plate with an adhesive to the surface side of the wafer on which the protective film is formed;
A polishing step of polishing the back surface of the wafer to the kerf;
A separation step of removing the adhesive and removing the reinforcing plate to separate the integrated circuit element with an antenna;
A method for producing RF powder, comprising: A method in which a single particle has a resonant circuit formed on a substrate and is sensitive to an external electromagnetic field, and manufacturing RF powder composed of a large amount of the particle,
Producing a large number of circuit elements to be the particles on a wafer using exposure by parallel rays or X-rays;
A gas dicing step of forming a kerf at a position for separating the circuit element on the surface of the wafer on which the resonance circuit is formed;
A protective film forming step of covering the periphery of the circuit element with a protective film;
A reinforcing step of attaching a reinforcing plate with an adhesive to the surface side of the wafer on which the protective film is formed;
A polishing step of polishing the back surface of the wafer to the kerf;
A separation step of separating the circuit element by removing the adhesive and removing the reinforcing plate;
A method for producing RF powder, comprising:   10. The method for producing RF powder according to claim 8, wherein the adhesive is a material that is soluble in an organic solvent. The RF powder manufacturing method according to claim 8, wherein the reinforcing plate is a ceramic plate.

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