1. Field of the Invention
In this specification, a terminal structure including a conductor which penetrates an insulating film will be described. Further, an electronic device provided with a terminal having such a structure will be described.
2. Description of the Related Art
A resin layer formed by curing a prepreg is applied to a support, an insulating film, a protective material, or the like of a printed wiring board, an electronic device, or the like (for example, see Patent Documents 1 to 3).
Since a multilayer wiring is formed, an opening for penetrating a resin layer formed from a prepreg is formed in this layer in order to form an electrical connection portion with the outside. For example, Patent Document 1 discloses that an insulating layer of a printed wiring board is formed from a prepreg and an opening is formed in the insulating layer with laser treatment, drilling, or punching-out.
Patent Documents 2 and 3 disclose that an opening is formed in a cured prepreg by performing a step of laser beam irradiation or a photolithography step in order to form a connection terminal for an electronic device sealed with the cured prepreg.
As disclosed in Patent Document 1, an opening is formed in a resin film formed from a prepreg by drilling, punching-out, and laser beam treatment. For formation of an opening in a resin film with which an electronic element is sealed, drilling and punching-out are not suitable. Treatment with a laser beam is employed in order not to damage the electronic element.
However, a step of forming an opening with a laser beam takes much time. In addition, in the ease of employing the step of forming an opening with a laser beam, a mechanical impact on an electronic element is small as compared with drill treatment or punching-out; however, the possibility that performance of the electronic element is degraded by energy of a laser beam cannot be completely eliminated. In the study by inventors of the present invention, it is found that characteristics of an electronic element with a small size and a high-performance electronic element driven with low voltage are degraded due to laser beam irradiation in a step of forming an opening in a sealing layer in some cases.
In addition, an opening is formed with a laser beam in a sealing layer with which an electronic element is sealed, dust generated in this step adversely effects the electronic element in some cases.
By using a prepreg including a reinforcing material such as a glass fiber or a glass filler, an electronic element can be sealed with a resin film including the reinforcing material; therefore, the strength of the electronic element can be increased. Meanwhile, in the case where an opening is formed in the sealing film in order to expose an extraction terminal of an electronic element, the reinforcing material is also needed to be removed with the resin film. In the case where an opening is formed with a laser beam, judgment whether both the resin film and the reinforcing material are removed is difficult and needs a skill. Thus, depending on the skill of an operator, the resin film and/or the reinforcing material might be insufficiently removed and thus the areas of regions exposed in openings might vary. Accordingly, the values of connection resistance of two conductors electrically connected through an opening vary, which makes it difficult to manufacture an electric element having electric characteristics with a designed value.
A technical object in this specification is to improve the reliability of a terminal structure including a conductor which penetrates a cured prepreg.
Another technical object in this specification is to provide a method for manufacturing a terminal structure in which an influence of a laser beam is removed as much as possible.
A method for manufacturing a terminal structure and a method for manufacturing an electronic element according to one embodiment of the present invention include the steps of forming a first conductor over a first insulating film; disposing a prepreg having a plurality of openings over the first insulating film so that at least one of the openings overlaps with the first conductor; providing a conductive paste in at least one of the openings which overlaps with the first conductor; and curing the conductive paste and the prepreg by heat treatment, thereby forming a second conductor and a second insulating film.
A method for manufacturing a terminal structure and a method for manufacturing an electronic element according to one embodiment of the present invention include the steps of forming a first conductor over a first insulating film; providing a conductive paste on the first conductor; disposing a prepreg having a plurality of openings over the first insulating film so that at least one of the openings overlaps with the conductive paste; and curing the conductive paste and the prepreg by heat treatment, thereby forming a second conductor and a second insulating film.
A method for manufacturing a terminal structure and a method for manufacturing an electronic element according to one embodiment of the present invention include the steps of forming a first conductor over a first insulating film; providing a conductive paste in at least one of openings formed in a prepreg; disposing the prepreg over the first insulating film so that the at least one of the openings in which the conductive paste is provided overlaps with the first conductor; and curing the conductive paste and the prepreg by heat treatment, thereby forming a second conductor and a second insulating film.
A method for manufacturing a terminal structure and a method for manufacturing an electronic element according to one embodiment of the present invention include the steps of forming a first conductor over a first insulating film; forming one or more openings in a region of a prepreg, which overlaps with the first conductor when the prepreg is disposed over the first insulating film; disposing the prepreg having one or more openings over the first insulating film so that at least one of the openings overlaps with the first conductor; providing a conductive paste in at least one of the openings which overlaps with the first conductor; and curing the conductive paste and the prepreg by heat treatment, thereby forming a second conductor and a second insulating film.
A method for manufacturing a terminal structure and a method for manufacturing an electronic element according to one embodiment of the present invention include the steps of forming a first conductor over a first insulating film; providing a conductive paste on the first conductor; forming one or more openings in a region of a prepreg, which overlaps with the first conductor when the prepreg is disposed over the first insulating film; disposing the prepreg having one or more openings over the first insulating film so that at least one of the openings overlaps with the conductive paste; and curing the conductive paste and the prepreg by heat treatment, thereby forming a second conductor and a second insulating film.
A method for manufacturing a terminal structure and a method for manufacturing an electronic element according to one embodiment of the present invention include the steps of forming a first conductor over a first insulating film; forming one or more openings in a region of a prepreg, which overlaps with the first conductor when the prepreg is disposed over the first conductor; providing a conductive paste in at least one of the openings in the prepreg; disposing the prepreg over the first insulating film so that the at least one of the openings in which the conductive paste is provided overlaps with the first conductor; and curing the conductive paste and the prepreg by heat treatment, thereby forming a second conductor and a second insulating film.
A step of forming a third conductor which is electrically connected to the second conductor can be added to the method for manufacturing the terminal structure and the electronic element according to any one of the above six embodiments. As an example of such a step, a step of electrically connecting an antenna to the second conductor is given.
In the method for manufacturing an electronic device, according to any one of the above six embodiments, in the case where an electronic element is provided over a substrate which is used when the electronic element is formed, a step of separating the substrate from the electronic element can be performed.
In one embodiment of the methods for manufacturing the terminal structure and the electronic device described in this specification, it is not necessary to perform a step of forming an opening with a laser beam after a prepreg is cured. Thus, an adverse effect in the step of forming an opening, such as a defect due to dust or damage caused by a laser beam, can be prevented.
In the accompanying drawings:
Embodiments of the invention disclosed in this specification will be described below with reference to the accompanying drawings. Note that in the drawings referred to in this specification, components denoted by the same reference numerals in different drawings represent the same components. Therefore, the description regarding such components, which is repetitive, will be omitted in some cases.
In addition, it is easily understood by those skilled in the art that modes of the invention disclosed in this specification are not limited to the description in the embodiments and can be modified in various ways. That is, the invention disclosed in this specification should not be interpreted as being limited to the description of the embodiments.
In this embodiment, a terminal structure provided with a conductor which penetrates a resin film formed from a cured prepreg and a method for manufacturing the terminal structure will be described. Further, in this embodiment, an electronic device provided with a terminal having such a structure and a method for manufacturing the electronic device will be described.
A terminal structure of this embodiment, a structure of an electronic device of this embodiment, a method for manufacturing the terminal structure, and a method for manufacturing the electronic device will be described with reference to
As illustrated in
In
As the substrate 100, a substrate such as a semiconductor substrate, a glass substrate, a quartz substrate, a sapphire substrate, a ceramic substrate, a stainless steel substrate, or a metal substrate can be used. As a semiconductor substrate, a silicon wafer obtained by slicing an ingot, an SOI substrate in which a single crystal semiconductor layer is formed over a substrate with an insulating film provided therebetween, or the like can be used. Further, in the case where a silicon wafer obtained by slicing an ingot is used as the substrate 100, the electronic element 110 including a semiconductor region can be formed using the silicon wafer (the substrate 100).
Each of the insulating films 101 to 103 may have either a single-layer structure or a layered structure. Insulating films used as the insulating films 101 to 103 are selected in consideration of the conditions of a manufacturing process of the electronic element 110 and the functions of these films. For example, an insulating film containing silicon and/or germanium as its component, such as a silicon oxide film, a silicon nitride film, a silicon oxynitride film, a silicon nitride oxide film, a germanium oxide film, a germanium nitride film, a germanium oxynitride film, or a germanium nitride oxide film can be used. Further, the following may be used: an insulating film formed from oxide of metal, such as aluminum oxide, tantalum oxide, or hafnium oxide; an insulating film formed from nitride of metal, such as aluminum nitride; an insulating film formed from oxynitride of metal, such as aluminum oxynitride; or an insulating film formed from nitride oxide of metal, such as aluminum nitride oxide. Furthermore, a resin film formed from a resin material such as acrylic, polyimide, polyamide, polyimideamide, or benzocyclobutene may be used. Note that in this specification, oxynitride is a substance in which the content of oxygen is larger than that of nitrogen and nitride oxide is a substance in which the content of nitrogen is larger than that of oxygen.
There are the following typical examples of the method for forming these insulating films: a CVD method (chemical vapor deposition method) such as a PECVD (plasma-excited CVD) method or a thermal CVD method; a PVD method (physical vapor deposition method) such as a sputtering method or a vapor deposition method; an ALD method (atomic layer deposition method); a method for forming a film with a liquid or paste material, such as a spin-coating method, a droplet discharging method, or a dip-coating method; solid-phase oxidation treatment or solid-phase nitridation treatment with plasma or heat; and the like.
Further, each of the conductors 112 and 113 may have either a single-layer structure or a layered structure. Each of the conductors 112 and 113 can be formed using a metal film containing single metal such as tantalum, tungsten, titanium, molybdenum, aluminum, chromium, niobium, gold, silver, copper, or platinum, as its main component, an alloy film, a metal compound film, or the like. For example, as the metal film, a copper film, a pure aluminum film, and an aluminum film to which Si, Nb, or the like is added are given. As the alloy film, an aluminum-copper alloy film and an aluminum-neodymium alloy film are given. As the metal compound film, a metal nitride film such as a titanium nitride film or a tungsten nitride film, and a silicide film such as a nickel silicide film or a cobalt silicide film are given. These conductive films can be formed with a PVD method such as a sputtering method or a vapor deposition method; a method for forming a film with a liquid or paste material, such as a printing method, a droplet discharging method, or a dip-coating method; a soldering method; a plating method; or the like.
The electronic element 110 is manufactured, and then, the insulating film 104 is formed to cover the electronic element 110 as illustrated in
Then, as illustrated in
In this embodiment, the electronic element 110 is sealed with an insulating film (a resin film) formed using a prepreg.
As the uncured matrix resin 132 (hereinafter referred to as a “matrix resin 132”), a resin cured by heat treatment can be used. For example, a thermosetting resin such as an epoxy resin, an unsaturated polyester resin, a polyimide resin, a bismaleimide-triazine resin, or a cyanate resin can be used. Alternatively, a thermoplastic resin such as a polyphenylene oxide resin, a polyetherimide resin, or a fluorocarbon polymer can be used. For example, when the matrix resin 132 is formed using a polyimide resin, the matrix resin 132 is cured to form an insulating film folioed using a polyimide resin. Note that the number of resins used for the matrix resin 132 is not limited to one, and a plurality of resins may be used.
Note that in this specification, an uncured resin and an uncured prepreg refer to both a resin and a prepreg in an uncured state and a resin and a prepreg in an incompletely cured state. The incompletely cured state is also referred to as a semi-cured state.
As the reinforcing material 131 used for the prepreg 130, fiber, a sheet fibrous body (also referred to as a fibrous sheet), a filler, and the like are given. The sheet fibrous body is a sheet substance formed using fiber and for example, a woven fabric and a nonwoven fabric each correspond to the sheet fibrous body. The way of weaving a woven fabric used for the sheet fibrous body is not particularly limited and for example, a plain-woven fabric, a twilled fabric, a satin-woven fabric, or the like can be used as the sheet fibrous body.
High-strength fiber is preferably used as fiber used for the reinforcing material 131. The high-strength fiber is specifically fiber with a high modulus of elasticity in tension or fiber with a high Young's modulus. As the high-strength fiber, a polyvinyl alcohol fiber, a polyester fiber, a polyamide fiber, a polyethylene fiber, an aramid fiber, a polyparaphenylene benzobisoxazole fiber, a glass fiber, a carbon fiber, and the like are given. As the glass fiber, glass fiber using E glass, S glass, D glass, Q glass, or the like is given. For example, a woven fabric formed from glass fiber is called glass cloth.
There is no particular limitation on a yarn bundle (e.g., the cross-sectional shape or the processing method) used for the reinforcing material 131. The cross-sectional shape may be a circular shape, an elliptical shape, or a flat shape. A sheet fibrous body formed using a yarn bundle which has been subjected to fiber opening is preferably used for the reinforcing material 131 because the yarn bundle subjected to fiber opening has a large width, has a smaller number of single yarns in the thickness direction, and thus is easily flattened in cross section. Flattening the yarn bundle in cross section makes the thickness of the fibrous body small, which reduces the thickness of the reinforcing material 131. Accordingly, the uncured prepreg 130 can be thin.
In this embodiment, a sheet fibrous body is employed as the reinforcing material 131. In this case, the prepreg 130 can be formed as follows: a sheet fibrous body is impregnated with a composition obtained by dilution of the matrix resin 132 with an organic solvent; and then the organic solvent is volatilized by drying so that the matrix resin 132 is semi-cured.
Note that instead of the prepreg 130, a film formed using an uncured resin which does not include the reinforcing material 131 can be used. It is preferable to use the prepreg 130 including the reinforcing material 131 because the electronic device can be reinforced.
In this embodiment, a plurality of openings 133 (through holes) is formed in the uncured prepreg 130 in order to form a terminal portion of the electronic device.
Then, as illustrated in
The number, the size, the shape, the layout, and the like of the openings 133 are determined in consideration of characteristics (e.g., a resistance value) which are needed for a circuit layout and a circuit design. In a state in which the prepreg 130 is fixed to the insulating film 104, at least one of the openings 133 may overlap with the conductor 114. The description the opening 133 overlaps with the conductor 114″ includes the case where the whole of the opening 133 overlaps with the conductor 114 and the case where part of the opening 133 overlaps with the conductor 114.
In this embodiment, the openings 133 are formed in the whole area of the prepreg 130; thus, one or more openings 133 can overlap with the conductor 114 without particular positioning of the openings 133 and the conductor 114. That is, precise positioning of the openings 133 and the conductor 114 is not needed depending on the number, the size, the shape, the layout, and the like of the openings 133 formed in the prepreg 130.
In this embodiment, as illustrated in
In the case where the size of the opening 133 is small with respect to the conductor 114 as in
After the prepreg 130 in which the plurality of openings 133 is formed is attached to the insulating film 104, a conductive paste 140 is provided in the openings 133 which overlap with the conductor 114.
First, as illustrated in
A droplet discharge method (an inkjet method, a dispensing method, and the like are included), a printing method such as a screen printing method, or the like is employed in order to provide the conductive paste 140 in a desired region of the prepreg 130. As illustrated in
Depending on the kind of the solvent included in the conductive paste 140, the matrix resin 132 included in the prepreg 130 is dissolved and the conductive particles (or the conductive powder) included in the conductive paste 140 are dispersed into the dissolved matrix resin 132 in some cases.
The main role of the solvent included in the conductive paste 140 is, in curing treatment of the prepreg 130, to prevent the matrix resin 132 from flowing to fill the opening 133 in which the conductive paste 140 is provided.
Next, the prepreg 130 and the conductive paste 140 are heated while being pressed so as to be cured. In this curing step, it is preferable that the prepreg 130 and the conductive paste 140 be heated while being pressed, and the curing step can be performed with a vacuum heat press. As illustrated in
As the conductive paste 140, it is preferable to select a substance which is cured at a temperature lower than the temperature at which the matrix resin 132 starts to become fluid. Since the conductive paste 140 is cured at a temperature lower than the temperature at which the matrix resin 132 starts to become fluid, the conductive paste 140 provided in the opening 133 can be cured before the matrix resin 132 flows into the opening 133 in which the conductive paste 140 is provided. As a result, the connection resistance between the conductor 114 and the conductor 141 can be lowered. In the case where the solvent included in the conductive paste 140 dissolves the matrix resin 132, the conductive paste 140 provided in the opening 133 prevents the matrix resin 132 from flowing into the opening 133.
Next, as illustrated in
The insulating film 135 for covering the conductor 114 is a resin film obtained by curing the prepreg 130. Since the openings 133C in which the conductive paste 140 is not provided are formed in the prepreg 130 illustrated in
After the step illustrated in
As illustrated in
Before the substrate 100 is cut, the prepreg 130 including the reinforcing material 131 may be attached to the substrate 100 side. Then, the prepreg 130 is cured to form an insulating film 136 which covers the rear surface of the substrate 100 as illustrated in
As illustrated in
The structure of the electronic device 183 is similar to that of the electronic device 181 in
Note that a prepreg including a reinforcing material is used for forming a sealing film in this embodiment; however, an uncured resin film which does not include a reinforcing material can be used instead of the prepreg.
As described above, when this embodiment is applied to the manufacture of a terminal structure, it is not necessary to perform a step of forming an opening in an insulating film for covering an electronic element or a conductor with a laser beam. Therefore, damage to the terminal or the electronic element caused by a laser beam, defects of the terminal or the electronic element due to dust generated in the step of forming an opening, and the like can be prevented.
In addition, a conductor which penetrates an insulating film formed from a prepreg can be easily manufactured. As specific effects, positioning of the openings formed in the insulating film in order to penetrate the conductor is not necessary, the sizes of the openings can be easily made uniform, or the like are given. As a result, a terminal and an electronic device which have electronic characteristics with the designed value can be easily manufactured, and the reliability of the terminal and the electronic device can be increased.
This embodiment can be combined with any of the other embodiments as appropriate.
In Embodiment 2, a terminal structure provided with a conductor which penetrates a resin film formed from a cured prepreg and a method for manufacturing the terminal structure will be described. Further, in this embodiment, an electronic device provided with a terminal having such a structure and a method for manufacturing the electronic device will be described.
According to the method for manufacturing a terminal structure and an electronic device in Embodiment 1, the prepreg 130 is fixed to the insulating film 104, and then the conductive paste 140 is provided in the opening in the prepreg 130. In Embodiment 2, a method for manufacturing a terminal structure and an electronic device in which a conductive paste 150 is provided over the conductor 114 and then the prepreg 130 is fixed to the insulating film 104 will be described.
First, as illustrated in
Next, the prepreg 130 having the plurality of openings 133 illustrated in
In the case where a solvent included in the conductive paste 150 dissolves the matrix resin 132 included in the prepreg 130, the conductive paste 150 is spread by the prepreg 130; thus, the conductive particles (or the conductive powder) of the conductive paste 150 which has not been filled in the openings 133 are dispersed into the matrix resin 132.
Then, the prepreg 130 and the conductive paste 150 are heated while being pressed so as to be cured. This curing step can be performed in a manner similar to that in
The steps of
Next, as illustrated in
The steps following the step of
As in Embodiment 1, the insulating film 161 for covering the conductor 114 is a resin film obtained by curing the prepreg 130 having the plurality of openings 133 in this embodiment; thus, the insulating film 161 has a structure which is similar to that of the insulating film 135. That is, the insulating film 161 includes a sheet fibrous body in which the plurality of openings 133 is formed. Further, the insulating film 161 includes a portion where the reinforcing material 131 and the conductive particles or the conductive powder exist in a region which overlaps with the conductor 151 in some cases, depending on the kind of the solvent included in the conductive paste 150.
As described above, when this embodiment is applied to the manufacture of a terminal structure, it is not necessary to perform a step of forming an opening in an insulating film for covering an electronic element or a conductor with a laser beam. Therefore, damage to the electronic element or the terminal caused by a laser beam, defects of the electronic element or the terminal due to dust generated in the step of forming an opening, and the like can be prevented.
In addition, a conductor which penetrates an insulating film formed from a prepreg can be easily manufactured. As specific effects, for example, high-accuracy positioning for determining where the conductor is formed is not necessary, and the sizes of the openings can be easily made uniform. As a result, the reliability of the electronic device can be increased.
This embodiment can be combined with any of the other embodiments as appropriate.
In Embodiment 3, a terminal structure provided with a conductor which penetrates a resin film formed from a cured prepreg and a method for manufacturing the terminal structure will be described. Further, in this embodiment, an electronic device provided with a terminal having such a structure and a method for manufacturing the electronic device will be described.
According to the method for manufacturing a terminal structure and an electronic device in Embodiment 1, the prepreg 130 is fixed to the insulating film 104, and then the conductive paste 140 is provided in the opening in the prepreg 130. In Embodiment 3, a method for manufacturing a terminal structure and an electronic device in which a conductive paste 170 is provided over the prepreg 130, and then the prepreg 130 is fixed to the insulating film 104 will be described.
As illustrated in
As illustrated in
When the conductive paste 170 is provided over the prepreg 130, part of the conductive paste 170 fills the openings 133. Depending on the kind of the solvent included in the conductive paste 170, the matrix resin 132 included in the prepreg 130 is dissolved and the conductive particles (or the conductive powder) included in the conductive paste 170 are dispersed into the dissolved matrix resin 132 in some cases.
Next, the prepreg 130 provided with the conductive paste 170 is attached onto the insulating film 104. The positioning of the prepreg 130 is performed in order that the opening 133 provided with the conductive paste 170 overlaps with the conductor 114. The prepreg 130 is closely attached to the insulating film 104, so that the conductive paste 170 in the opening 133 is in contact with the conductor 114 as illustrated in
Then, the prepreg 130 and the conductive paste 170 are heated while being pressed so as to be cured. This curing step can be performed in a manner similar to that in
Next, as illustrated in
The steps following the step of
As in Embodiment 1, the insulating film 163 for covering the conductor 114 is a resin film obtained by curing the prepreg 130 having the plurality of openings 133 in this embodiment; thus, the insulating film 163 has a structure which is similar to that of the insulating film 135. That is, the insulating film 163 includes a sheet fibrous body in which the plurality of openings 133 is formed. Further, the insulating film 163 includes a portion where the reinforcing material 131 and the conductive particles or the conductive powder exist in a region which overlaps with the conductor 171 in some cases, depending on the kind of the solvent included in the conductive paste 170.
As described above, when this embodiment is applied to the manufacture of a terminal structure, it is not necessary to perform a step of forming an opening in an insulating film for covering an electronic element or a conductor with a laser beam. Therefore, damage to the electronic element or the terminal caused by a laser beam, defects of the terminal or the electronic element due to dust generated in the step of forming an opening, and the like can be prevented.
In addition, a conductor which penetrates an insulating film formed from a prepreg can be easily manufactured. As specific effects, for example, high-accuracy positioning for determining where the conductor is formed is not necessary, and the sizes of the openings through which the conductor penetrates the insulating film can be easily made uniform. As a result, the reliability of the electronic device can be increased.
This embodiment can be combined with any of the other embodiments as appropriate.
According to the method for manufacturing a terminal structure in Embodiment 1, the openings 133 are formed in the entire surface of the prepreg 130 as illustrated in
As illustrated in
As illustrated in
As illustrated in
The opening 201, the openings 202, and the openings 203 can be formed by laser beam treatment, punching treatment, drill treatment, or the like in a manner similar to that of the opening 133 (see
With the use of a prepreg having at least one opening as in
In Embodiment 5, a sheet fibrous body which can be applied to the reinforcing material of the prepreg will be described.
As illustrated in
There is no particular limitation on a yarn bundle (the warp yarn 261 and the weft yarn 262) (e.g., the cross-sectional shape or the processing method) used for the sheet fibrous body 251. The cross-sectional shape may be a circular shape, an elliptical shape, or a flat shape. A yarn bundle which has been subjected to fiber opening is preferably used for the warp yarn 261 and the weft yarn 262 because the yarn bundle subjected to fiber opening has a large width, has a smaller number of single yarns in the thickness direction, and thus is easily flattened in cross section. For example, as illustrated in
As a means to increase the strength of a cured prepreg, reduction in area of a basket hole is given.
A woven fabric used for a sheet fibrous body is not limited to a plain-woven fabric.
Further, to protect an electronic device with the use of a cured prepreg more effectively, the area of the basket hole 263 of each of the sheet fibrous bodies (251, 252, and 253) is preferably smaller than the area of a portion of the electronic device, which is locally pressed when the electronic device is used. For example, in the case where the electronic device is pressed with a tool having a sharp tip, like a writing implement such as a pen or a pencil, the shape of the basket hole 263 is preferably a quadrangle having sides each of which has a length of greater than or equal to 0.01 mm and less than or equal to 0.2 mm.
This embodiment can be combined with any of the other embodiments as appropriate.
In Embodiment 6, as an example, a structure of an electronic device which is capable of transmitting and receiving data through wireless communication and a method for manufacturing the electronic device will be described.
Carrier waves are a signal of alternating current waves which is also referred to as a carrier. In wireless communication, the frequency or amplitude of carrier waves is changed (modulated) in accordance with a signal representing data to generate modulated waves, and data is communicated through transmission and reception of the modulated waves. There are some kinds of methods for modulating carrier waves. A modulation method in which data is represented by the amplitude of carrier waves is called amplitude modulation. A modulation method in which data is represented by the frequency of carrier waves is called frequency modulation.
As a specific example of the electronic device 300, an IC chip (also referred to as a wireless chip) which can communicate data without contact is given. In addition, a radio frequency identification (RFID) tag with which individual identification without contact is performed is given. The RFID tag is also referred to as an RF tag, a wireless tag, an electronic tag, or an IC tag.
An example of a structure of the electronic device 300 which can be used for an IC chip or an RFID tag will be described with reference to
First, the structure of the electronic device 300 in
The power source portion 311 is a device for supplying power to the electronic device 300 and includes, for example, a rectifier circuit 321, a power storage portion 322, and a constant voltage circuit 323. The rectifier circuit 321 is a circuit to generate a direct-current voltage from a signal (carrier waves) received by the antenna 301. The power storage portion 322 is a circuit to store the direct-current voltage generated by the rectifier circuit 321 and thus includes, for example, a plurality of capacitors. The constant voltage circuit 323 is a circuit to make the voltage generated by the rectifier circuit 321 constant.
The logic circuit portion 312 has a function of extracting data from the signal (the carrier waves) received by the antenna 301, a function of generating carrier waves, which represents data transmitted from the antenna 301, and the like. For example, the logic circuit portion 312 includes a demodulation circuit 331, a clock generation/correction circuit 332, a code recognition/judgment circuit 333, a memory controller 334, a memory device 335, an encoding circuit 336, and a modulation circuit 337.
The demodulation circuit 331 is a circuit to demodulate the carrier waves received by the antenna 301. The clock generation/correction circuit 332 is a circuit to generate a clock signal based on the signal output from the demodulation circuit 331 and to correct the clock signal.
The code recognition/judgment circuit 333 recognizes a code included in the carrier waves received by the antenna 301 and makes a judgment. Further, the code recognition/judgment circuit 333 has a cyclic redundancy check (CRC) function, for discriminating a transmission error. As the code recognized by the code recognition/judgment circuit 333, an end-of-frame (EOF) signal, a start-of-frame (SOF) signal, a flag, a command code, a mask length, a mask value, and the like are given.
The memory controller 334 generates, on the basis of the code recognized by the code recognition/judgment circuit 333, a signal for reading out data from the memory device 335. The memory device 335 includes at least a read-only memory (ROM). Examples of the ROM include a mask ROM and a PROM. Further, the memory device 335 may include a memory circuit such as a random access memory (RAM), which is capable of rewriting data. As the memory circuit capable of rewriting data, for example, a DRAM, an SRAM, an FeRAM, an EEPROM, or a flash memory can be used.
The encoding circuit 336 encodes data which is to be transmitted from the electronic device 300, such as data read out from the memory device 335, or the like. The modulation circuit 337 modulates the signal based on the data which has been encoded in the encode circuit 336 to generate carrier waves which can be transmitted from the antenna 301.
Next, the structure of the electronic device 300 in
The analog circuit portion 341 includes a resonance circuit 351 having a resonant capacitor, a constant voltage circuit 352, a rectifier circuit 353, a demodulation circuit 354, a modulation circuit 355, a reset circuit 356, an oscillator circuit 357, and a power supply control circuit 358.
The digital circuit portion 342 includes an RF interface 361, a control register 362, a clock controller 363, a central processing unit (CPU) 364, a CPU interface 365, an RAM 366, and an ROM 367.
The operation of the electronic device 300 in
The reset circuit 356 generates a signal which resets and initializes the digital circuit portion 342. For example, the reset circuit 356 generates a signal which rises after increase in a power supply voltage with delay as a reset signal. The oscillator circuit 357 changes the frequency and the duty ratio of a clock signal in accordance with a control signal generated by the constant voltage circuit 352. The demodulation circuit 354 is a circuit which demodulates a received signal, and the modulation circuit 355 is a circuit which modulates a signal so that data to be transmitted is included in carrier waves.
For example, when a modulation method by which a signal is processed in the electronic device 300 is an amplitude shift keying (ASK) method, which is one of amplitude modulation methods, the demodulation circuit 354 is preferably formed using a low-pass filter. The demodulation circuit 354 binarizes the received signal based on variation in amplitude. On the other hand, the modulation circuit 355 changes the resonance point of the resonance circuit 351, thereby changing the amplitude of the signal.
The clock controller 363 generates a control signal for changing the frequency and the duty ratio of a clock signal in accordance with a power supply voltage or a current consumed in the CPU 364. The power supply voltage is monitored by the power supply control circuit 358.
The signal received by the antenna 301 is demodulated by the demodulation circuit 354. The demodulated signal is decomposed into a control command, data, and the like by the RF interface 361. The control command is stored in the control register 362. The control command includes an instruction to a circuit included in the digital circuit portion 342, such as an instruction for reading out data from the ROM 367, an instruction for writing data to the RAM 366, or an arithmetic instruction to the CPU 364.
The CPU 364 accesses the ROM 367, the RAM 366, and the control register 362 via the CPU interface 365. The CPU interface 365 generates an access signal which allows the CPU 364 to access any of the ROM 367, the RAM 366, and the control register 362 in accordance with an address requested by the CPU 364.
There are several arithmetic processing methods of the CPU 364, and a method in which processing is performed by software is one of the methods. In this method, for example, the ROM 367 stores an operating system (OS) and the CPU 364 reads out a program stored in the ROM 367 to execute. Another method is a method in which processing is conducted by a dedicated arithmetic circuit, that is, a method in which processing is conducted by hardware. Another method is a method in which hardware and software are used. In this method, part of arithmetic processing is conducted by a dedicated arithmetic circuit and the other part of the arithmetic processing is conducted by the CPU 364 with the use of a program.
Next, a method for manufacturing the electronic device 300 in this embodiment will be described. This manufacturing method includes a step of separation of a substrate which is used for manufacturing an electronic element included in the functional circuit 302.
For example, in the manufacturing method described in Embodiment 1, a separation film (e.g., a film including silicon) is formed between the substrate 100 and the insulating film 101 serving as a base and removed by etching, so that the electronic device can be separated from the substrate 100. Alternatively, the electronic device can be separated from the substrate 100 in such a manner that a separation film which includes metal as its main component is formed between the substrate 100 and the insulating film 101 serving as a base and physical force is applied to the separation film in order to cause separation along the separation film. An example of the method for manufacturing the electronic device 300, to which the latter method is applied, will be described below with reference to
First, as illustrated in
Before the separation film 402 is formed, a base film 403 is formed on and in close contact with the glass substrate 400. The base film 403 is a base film of the separation film 402 and is formed in order to improve adhesion between the separation film 402 and the glass substrate 400. The base film 403 can be formed using an insulating film with a single-layer structure or a layered structure. As the insulating film used to form the base film 403, a silicon oxide film, a silicon oxynitride film, a silicon nitride oxide film, a silicon nitride film, a metal oxide film, or the like can be used. Here, a silicon oxynitride film with a thickness of 100 nm is formed with a PECVD method.
Next, the separation film 402 is formed to be in contact with the base film 403. Here, as the separation film 402, a tungsten film with a thickness of 50 nm is formed with a sputtering method.
In this manufacturing method, separation is caused preferentially inside the separation film 402 and/or at the interface between the separation film 402 and the base insulating film 401 by applying mechanical force to the separation film 402 so that the functional circuit 302 is separated from the glass substrate 400. In order that such separation may be caused, the separation film 402 is formed using a tungsten film, a molybdenum film, an alloy film of tungsten and molybdenum, an oxide film of tungsten and/or molybdenum, an oxynitride film of tungsten and/or molybdenum, a nitride oxide film of tungsten and/or molybdenum, or a nitride film of tungsten and/or molybdenum, for example. Further, the separation film 402 can be formed using a stack of films selected from the above. These films can be formed with a sputtering method, a PECVD method, a droplet discharging method, or the like.
The separation film 402 may be formed in such a manner that a tungsten film, a molybdenum film, or an alloy film of tungsten and molybdenum is formed as a first layer and an oxide film, an oxynitride film, a nitride oxide film, or a nitride film of the first layer is formed as a second layer. Alternatively, the separation film 402 may be formed in such a manner that a tungsten film, a molybdenum film, or an alloy film of tungsten and molybdenum is formed over the base film 403 and the film is subjected to oxidation treatment. As the oxidation treatment, thermal oxidation treatment, plasma oxidation treatment with O2 or N2O plasma, surface treatment with a solution having strong oxidizing power, such as ozone water, or the like can be used.
Next, the base insulating film 401 with a single-layer structure or a stacked-layer structure is formed to be in contact with the separation film 402. An insulating film which can endure later steps of manufacturing the electronic device 300 is selected as the base insulating film 401 and can be formed in a manner similar to that of the insulating film 101 in
Next, the functional circuit 302 is manufactured over the base insulating film 401. A plurality of functional circuits 302 is simultaneously manufactured over the glass substrate 400 in the same process. A process of manufacturing two functional circuits 302 each including an n-channel transistor and a p-channel transistor is illustrated in drawings.
As illustrated in
Next, a resist mask is formed over the semiconductor film 405 and the semiconductor film 405 is etched to have a desired shape using the resist mask, so that semiconductor films 420 and semiconductor films 430 are formed over the base insulating film 401 as illustrated in
Next, as illustrated in
Next, as illustrated in
Next, as illustrated in
In order to form these regions, first, resist masks which cover the semiconductor films 430 are formed. An impurity element which imparts n-type conductivity is added to the semiconductor films 420 with the use of the conductors 441 as masks, so that the n-type low-concentration impurity regions 423 are formed in the semiconductor films 420. Regions in the semiconductor films 420, where the impurity element is not added in this step, become channel formation regions 421. Then, after the resist masks which cover the semiconductor films 430 are removed, resist masks which cover the semiconductor films 420 are formed. An impurity element which imparts p-type conductivity is added to the semiconductor films 430 with the use of the conductors 440 as masks, so that the p-type high-concentration impurity regions 432 are formed in the semiconductor films 430. Then, the resist masks are removed. Regions in the semiconductor films 430, where the impurity element is not added in the step of adding the impurity element, become channel formation regions 431.
As for the steps illustrated in
In this embodiment, phosphorus (P), arsenic (As), or the like can be used as the impurity element which imparts n-type conductivity, and boron (B), aluminum (Al), gallium (Ga), or the like can be used as the impurity element which imparts p-type conductivity.
Next, as illustrated in
Next, the insulating film 407 and the insulating film 406 are subjected to etching. This etching step is performed by anisotropic etching mainly in a perpendicular direction. By such anisotropic etching, sidewalls formed using the insulating film 407 can be formed on side surfaces of the conductors 441 and the conductors 442 as illustrated in
Next, as illustrated in
Next, an insulating film 408 is formed so as to cover the semiconductor films 420, the semiconductor films 430, the conductors 441, and the conductors 442. Then, conductors 443 to 445 are formed over the insulating film 408.
The insulating film 408 can be formed in a manner similar to that of the insulating film 103 in
Next, in order that the conductors 443 and the conductors 444 are electrically connected to the n-type high-concentration impurity regions 422 and the p-type high-concentration impurity regions 432, respectively, the insulating film 408 is etched so that openings are formed. Then, a conductive film to be the conductors 443 to 445 is formed over the insulating film 408. The conductive film can be formed in a manner similar to that of the conductor 113 in
The conductors 443 are electrically connected to the n-type high-concentration impurity regions 422 and each of them functions as a source electrode, a source wiring, a drain electrode, or a drain wiring of the n-channel transistor. The conductors 444 are electrically connected to the p-type high-concentration impurity regions 432 and each of them functions as a source electrode, a source wiring, a drain electrode, or a drain wiring of the p-channel transistor. Further, the conductor 445 forms a portion in which the functional circuit 302 and the antenna 301 are electrically connected to each other.
Through the above steps, electronic elements (n-channel transistors 491 and p-channel transistors 492) of the functional circuits 302 are completed. Next, an example of steps of forming a connection terminal of the functional circuit 302 and the antenna 301 is described with reference to
As illustrated in
Next, a conductor 446 which is electrically connected to the conductors 445 is formed over the insulating film 409. Here, a titanium film with a thickness of 100 nm to 300 nm is formed by a sputtering method and etched to have the predetermined shape so that the conductor 446 is formed.
A prepreg 460 which includes an uncured matrix resin 462 including a reinforcing material 461 is prepared. The matrix resin 462 is heated to be cured. A prepreg which is similar to the prepreg 130 in
The prepreg 460 has a plurality of openings 463 in a region which overlaps with the conductor 446, like the prepreg 212 illustrated in
Then, the prepreg 460 is attached to the insulating film 409 so that the openings 463 overlap with the conductor 446 as illustrated in
Next, as illustrated in
Next, the conductive paste 450 and the prepreg 460 are cured. With a vacuum heat press, the conductive paste 450 and the prepreg 460 are heated while the prepreg 460 is pressed so that the conductive paste 450 and the prepreg 460 are cured. As illustrated in
Trough the above steps, the terminal portion 455 of the functional circuit 302 is completed. The terminal portion 455 is a connection portion which is electrically connected to the antenna 301. The terminal portion 455 includes the conductor 445, the conductor 446, and the conductor 451.
In this embodiment, the functional circuit 302 is not damaged by a laser beam in the process of manufacturing the terminal portion 455, whereby miniaturization and high performance of the electronic elements of the functional circuit 302 are easily achieved. Thus, a high performance circuit such as the functional circuit 302 including the CPU 364 illustrated in
Next, a step of separating the functional circuits 302 from the glass substrate 400 is performed. This separation step can be performed as follows, for example.
First, irradiation with a UV laser beam is performed from an insulating film 410 side so that a groove (not illustrated) is formed in a stack over the glass substrate 400 so as to reach the separation film 402. By formation of the groove, separation is caused inside the separation film 402 and/or at the interface between the base insulating film 401 and the separation film 402. Accordingly, the plurality of functional circuits 302 can be separated from the glass substrate 400 with relatively weak force (force that can be applied by a hand). Next, as illustrated in
Then, as illustrated in
Next, in order to protect the portion which is exposed due to removal of the glass substrate 400, a protective film which is formed using a prepreg including a reinforcing material is formed. For formation of the protective film, the one which is similar to the prepreg 460 used for forming the insulating film 410 can be used. The prepreg 460 which has not been cured is attached to the base insulating film 401, and the prepreg 460 is cured by a vacuum heat press with the prepreg 460 closely attached to the base insulating film 401. As a result, as illustrated in
Next, the stack held by the film 470 is divided into the individual functional circuit 302. This step can be performed by dicing, scribing, or the like. Here, scribing with the use of a UV laser beam is performed. Irradiation with a UV laser beam is performed from the insulating film 411 side, so that a groove is formed in the stack held by the film 470. As illustrated in
Next, the antenna 301 is electrically connected to the functional circuit 302. Here, as the antenna 301, a film antenna including a film 500 formed using a resin such as polyester and a conductor 501 formed over the film 500 is used. As the film 500, a film which has flexibility and is formed using an insulating material is preferably used. Since the functional circuit 302 has a structure in which the electronic elements are sealed with the insulating film 410 and the insulating film 411 each of which is formed using a resin, the functional circuit 302 is flexible and bendable. Therefore, when the antenna 301 is formed using a film antenna which is bendable, the electronic device 300 can also be flexible.
For example, as the film 500, a resin film such as a polyester film, a polycarbonate film, an acrylic film, or a polyimide film can be used. The conductor 501 includes a portion forming a main body of the antenna and a terminal portion which is electrically connected to the functional circuit 302. A surface of the conductor 501 is covered with a layer formed using an insulating material such as a resin, except for the terminal portion.
As illustrated in
The conductor 501 may have a suitable structure (e.g., a shape, a size) in accordance with the frequency band of carrier waves transmitted and received by the electronic device 300, the communication distance, or the like. Three examples of the structure of the antenna 301 (the conductor 501) are described with reference to
For example, when the frequency band is from the 125 kHz band to the 135 kHz band or the 13.56 MHz band, a loop antenna, a coil antenna, or a spiral antenna may be used as the antenna 301.
In addition, the electronic device 300 of this embodiment may be embedded in paper or interposed between two plastic substrates, whereby an IC card can be manufactured. Further, the electronic device 300 in
Further, the electronic device 300 may be used by being fixed to a variety of goods and objects. As a method for fixing the electronic device 300 to the goods and objects, there are methods such as embedding the electronic device 300 in the goods and objects, and attaching the electronic device 300 to the surface of the goods and objects. Since the electronic device 300 of this embodiment has flexibility, the appearance of an object to which the electronic device 300 is attached is unlikely to be spoiled, and the electronic device 300 can be fixed to a curved surface. Further, as the goods and objects to which the electronic device 300 is fixed, for example, the following is given: packaging containers (such as wrapping paper and bottles), recording media (such as Blu-ray Discs, DVDs, and USB memories), clothing and accessories (such as bags, glasses, and clothing), foods, plants, animals (such as livestock and pets), commodities, and shipping tags and labels on products and baggage. When the electronic device 300 is fixed to these goods and objects, inspection, distribution management, historical management of the objects, and the like are easily systematized.
For example, when the electronic device 300 is fixed to a shipping tag or a price tag of a product and data stored in the electronic device 300 is read with a reader/writer which is provided beside a conveyor belt, data on a manufacturing process, a distribution process, a delivery destination, and the like is obtained and thus product inspection and stock management can be performed with high efficiency.
This embodiment can be combined with any of the other embodiments as appropriate.
This application is based on Japanese Patent Application serial no. 2009-241992 filed with Japan Patent Office on Oct. 21, 2009, the entire contents of which are hereby incorporated by reference.
Number | Date | Country | Kind |
---|---|---|---|
2009-241992 | Oct 2009 | JP | national |
Number | Name | Date | Kind |
---|---|---|---|
5075166 | Sikorski et al. | Dec 1991 | A |
5597631 | Furumoto et al. | Jan 1997 | A |
5770313 | Furumoto et al. | Jun 1998 | A |
5879502 | Gustafson | Mar 1999 | A |
5888609 | Karttunen et al. | Mar 1999 | A |
6224965 | Haas et al. | May 2001 | B1 |
6252176 | Kuramochi et al. | Jun 2001 | B1 |
6403221 | Nakamura et al. | Jun 2002 | B1 |
6476330 | Otsuka et al. | Nov 2002 | B2 |
6482495 | Kohama et al. | Nov 2002 | B1 |
6497991 | Ishiguro | Dec 2002 | B1 |
6530147 | Haas et al. | Mar 2003 | B1 |
6805958 | Nakamura et al. | Oct 2004 | B2 |
6926794 | Kohama et al. | Aug 2005 | B2 |
7049178 | Kim et al. | May 2006 | B2 |
7061083 | Usami et al. | Jun 2006 | B1 |
7067392 | Yamazaki et al. | Jun 2006 | B2 |
7193308 | Matsui | Mar 2007 | B2 |
7465674 | Tamura et al. | Dec 2008 | B2 |
7485489 | Björbell | Feb 2009 | B2 |
7504317 | Aoki et al. | Mar 2009 | B2 |
7510950 | Tsurume et al. | Mar 2009 | B2 |
7564121 | Sugimoto | Jul 2009 | B2 |
7583512 | Ryu et al. | Sep 2009 | B2 |
7667310 | Dozen et al. | Feb 2010 | B2 |
7786576 | Kodaira | Aug 2010 | B2 |
7880091 | Miyamoto et al. | Feb 2011 | B2 |
8143708 | Oikawa et al. | Mar 2012 | B2 |
8338931 | Dozen et al. | Dec 2012 | B2 |
20040016118 | Haas et al. | Jan 2004 | A1 |
20050233122 | Nishimura et al. | Oct 2005 | A1 |
20060029726 | Mok et al. | Feb 2006 | A1 |
20060105153 | Jang et al. | May 2006 | A1 |
20070004125 | Watanabe et al. | Jan 2007 | A1 |
20070020932 | Maruyama et al. | Jan 2007 | A1 |
20070069375 | Sugimoto | Mar 2007 | A1 |
20070171992 | Shameli et al. | Jul 2007 | A1 |
20070181875 | Yamazaki et al. | Aug 2007 | A1 |
20070235220 | Shin et al. | Oct 2007 | A1 |
20070278563 | Takano et al. | Dec 2007 | A1 |
20080012126 | Dozen et al. | Jan 2008 | A1 |
20080044940 | Watanabe et al. | Feb 2008 | A1 |
20080083954 | Tokunaga | Apr 2008 | A1 |
20080224940 | Sugiyama et al. | Sep 2008 | A1 |
20080224941 | Sugiyama et al. | Sep 2008 | A1 |
20080242005 | Dozen et al. | Oct 2008 | A1 |
20080303140 | Ohtani et al. | Dec 2008 | A1 |
20080311706 | Dozen et al. | Dec 2008 | A1 |
20090057875 | Aoki et al. | Mar 2009 | A1 |
20090085182 | Yamazaki et al. | Apr 2009 | A1 |
20090139761 | Echigo et al. | Jun 2009 | A1 |
20090289341 | Yamazaki et al. | Nov 2009 | A1 |
20090302455 | Chida et al. | Dec 2009 | A1 |
20090302457 | Chida et al. | Dec 2009 | A1 |
20090314527 | Hatano et al. | Dec 2009 | A1 |
20100171221 | Chida | Jul 2010 | A1 |
20110030212 | Hamatani et al. | Feb 2011 | A1 |
20110032679 | Baek et al. | Feb 2011 | A1 |
20110032684 | Hamatani et al. | Feb 2011 | A1 |
Number | Date | Country |
---|---|---|
1 092 739 | Apr 2001 | EP |
1 589 797 | Oct 2005 | EP |
05-190582 | Jul 1993 | JP |
05-286065 | Nov 1993 | JP |
07-007246 | Jan 1995 | JP |
10-092980 | Apr 1998 | JP |
2001-331120 | Nov 2001 | JP |
2002-198658 | Jul 2002 | JP |
2002-290006 | Oct 2002 | JP |
2003-049388 | Feb 2003 | JP |
2003-228695 | Aug 2003 | JP |
2004-362341 | Dec 2004 | JP |
2007-091822 | Apr 2007 | JP |
2008-257710 | Oct 2008 | JP |
2008-262547 | Oct 2008 | JP |
WO 9609158 | Mar 1996 | WO |
WO 0101740 | Jan 2001 | WO |
WO 2004001848 | Dec 2003 | WO |
WO 2008041716 | Apr 2008 | WO |
Number | Date | Country | |
---|---|---|---|
20110090656 A1 | Apr 2011 | US |