JP2009171333A - Signal transmission integrated circuit device and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve noise resistance against external noise while attaining improvement in high-speed response performance. <P>SOLUTION: A magnetic coupling circuit Z is configured by layering in order a soft magnetic substance 3, a coil 4, an insulator 5, a coil 6 and a soft magnetic substance 8 via an insulating film 2 on a silicon substrate 1. A receiving circuit 15 is electrically connected to the coil 4, and a transmitting circuit 16 is electrically connected to the coil 6. The magnetic coupling circuit Z is integrated in one package together with the transmitting circuit 16 and the receiving circuit 15 and formed into input/output insulated type. The soft magnetic substances 3, 8 are configured to cover the surroundings of the coils 4, 6 and insulators 5, 7. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a signal transmission integrated circuit device for transmitting a signal while maintaining electrical insulation between input and output, and a method for manufacturing the same.

A photocoupler is generally known as this type of signal transmission integrated circuit device. This photocoupler is configured by arranging a light emitting element and a light receiving element so as to face each other. When an input signal is supplied to the light emitting element, the light emitting element emits light, and the light receiving element receives the emitted light to amplify the light receiving signal. The primary side input signal is transmitted to the secondary side. Besides the photocoupler, a configuration is known in which a coil is magnetically coupled to transmit a digital signal (see, for example, Patent Documents 1 and 2).
JP-T-2001-513276 JP-T-2001-521160

  In the recent information society, further improvement in information processing capability is required, and improvement in high-speed response performance and improvement in signal transmission reliability against disturbance are required. However, even if an existing photocoupler is applied to realize a circuit with good high-speed response performance, it leads to an increase in cost and is not practical. Moreover, even if the technical ideas described in Patent Documents 1 and 2 are applied, if external noise occurs, it is affected by the external noise, so that signal transmission reliability is lacking.

  An object of the present invention is to provide an input / output insulation type signal transmission integrated circuit device and a method for manufacturing the same, which can improve noise resistance against external noise while improving high-speed response performance.

  According to a first aspect of the present invention, there is provided a signal transmission integrated circuit device comprising: a first soft magnetic body portion formed on a support substrate; a coil-shaped first conductor formed on the first soft magnetic body portion; An insulator formed on one conductor, a coiled second conductor formed on the insulator and disposed opposite to the coiled first conductor, and formed on the second conductor An insulated transmission circuit having a second soft magnetic body portion, a transmission circuit electrically connected to one of the coiled first and second conductors, and a coil shape to which the transmission circuit is connected A receiving circuit electrically connected to the other of the two conductors, and the insulating transmission circuit, the transmitting circuit, and the receiving circuit are formed in an input / output insulation type by a circuit integrated in one package It is characterized by being.

  The invention according to claim 11 is a method of manufacturing an insulated transmission circuit of the signal transmission integrated circuit device according to claim 1, wherein a step of forming a first soft magnetic body portion on a support substrate, and the first soft magnetic circuit portion are formed. Forming a coiled first conductor on the magnetic body, forming a first insulator on the first conductor, and forming the coiled first conductor on the first insulator; And a step of forming a coil-shaped second conductor so as to be opposed to each other, and a step of forming a second soft magnetic body portion on the second conductor.

  According to the present invention, by applying a circuit using magnetic coupling and applying a soft magnetic material, the magnetic coupling rate can be improved and high-speed response performance can be improved, and noise resistance against external noise can be improved. It can be improved.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. In addition, the reference drawings shown below are shown schematically, and the thickness, width, length dimension, ratio, and the like of the components in each drawing are different from the actual structure. FIG. 2 is a plan view of a signal transmission integrated circuit device for insulating digital input / output processing to which a magnetic coupling circuit using a micro electro mechanical systems (MEMS) coil is applied. FIG. The structural cross section along line -A is shown. FIG. 3 is a cross-sectional perspective view of the magnetic coupling circuit.

  As shown in FIG. 1, a soft magnetic body 3, a coil 4, an insulator 5, a coil 6, an insulator 7, and a soft magnetic body 8 are sequentially arranged on a silicon substrate 1 as a support substrate via an insulating film 2. A stacked magnetic coupling circuit Z is configured. The soft magnetic body 3 constitutes a first soft magnetic body portion, and the soft magnetic body 8 constitutes second to fourth soft magnetic body portions. In addition, although embodiment which applied the silicon substrate 1 is shown, support substrates, such as an organic substrate which uses glass or a ceramic inorganic board | substrate, an epoxy etc. as a base material, can be applied as needed.

  The insulating film 2 is made of, for example, a silicon oxide film (SiO). The soft magnetic body 3 formed on the upper surface of the insulating film 2 is made of, for example, ferrite. The soft magnetic body 3 is formed into a donut disk shape with a film thickness (for example, several tens of μm to several hundreds of μm) that does not cause a magnetic saturation phenomenon when magnetic flux passes.

  On the upper surface of the soft magnetic body 3, the coil 4 is formed in a plane spiral shape from several turns to several tens of turns using a conductive material such as copper, aluminum, or gold. The insulator 5 is formed so as to cover the upper surface and side surfaces of the coil 4 with a material such as polyimide, for example. The insulator 5 is formed along the inner periphery of the spiral coil 4 in a plan view and along the outer periphery of the coil 4.

  The coil 6 is formed on a top surface of the insulator 5 by a conductive material such as copper, aluminum, or gold, and is formed in several planes to several tens of turns in a plane spiral shape. The coil 6 has a predetermined distance gap. Oppositely arranged in the vertical direction across the insulator 5. The coils 4 and 6 are formed in the same shape. The insulator 7 is formed so as to cover the upper surface and side surfaces of the coil 6 with a material such as polyimide, for example.

  The insulator 7 is formed along the inner periphery of the spiral coil 6 in plan and along the outer periphery of the coil 6. The soft magnetic body 8 is formed of ferrite, for example, along the outer periphery and the inner periphery of the insulators 5 and 7, and the upper surface of the insulator 7, and the outer shape thereof is formed into a donut disk shape. A portion where the soft magnetic body 8 is formed so as to surround the outer periphery of the insulators 5 and 7 is defined as a third soft magnetic body portion, and a portion formed so as to surround the inner periphery of the insulators 5 and 7 is defined as the third soft magnetic body portion. A portion formed along the upper surface of the insulator 7 is a second soft magnetic body portion.

  The soft magnetic body 3 is formed along the lower surface of the coil 4 and the lower surface of the insulator 5, and the soft magnetic body 8 is formed along the side surfaces of the insulators 5 and 7 and the upper surface of the insulator 7. The soft magnetic bodies 3 and 8 are configured to surround the coils 4 and 6 and the insulators 5 and 7.

  As shown in FIGS. 1 and 2, relay conductive layers 9 and 10 are formed in the soft magnetic material 3 on the upper surface of the insulator 2 so as to be separated from each other in the surface direction of the silicon substrate 1. These relay conductive layers 9 and 10 are each configured as a lead line by a material such as copper, aluminum, or gold. The insulating films 11 and 12 are formed of, for example, a silicon oxide film (SiOx) so as to cover the relay conductive layers 9 and 10, respectively. In this way, the magnetic coupling circuit Z is configured to include the layers 3 to 8 on the silicon substrate 1 with the insulating film 2 interposed therebetween.

  One end of each of the through electrodes 13 and 14 is made of the same material as that of the coil 4 on the upper surfaces of the relay conductive layers 9 and 10. The through electrode 13 is structurally and electrically connected to the inner end side of the coil 4 whose other end is a spiral shape. The through electrode 14 is structurally and electrically connected to the outer end side of the coil 4 whose other end is a spiral shape.

  On the surface layer of the silicon substrate 1, the electrical configurations of the receiving circuit 15 and the transmitting circuit 16 are configured. The reception circuit 15 and the transmission circuit 16 are configured to be separated from each other with the magnetic coupling circuit Z interposed in the surface direction of the silicon substrate 1. Since the receiving circuit 15 and the transmitting circuit 16 are not particularly related to the features of the present embodiment, the electrical structure on the silicon substrate 1 and in the substrate 1 in FIG. 1 is omitted.

  As shown in FIG. 2, a bonding wire 17 is structurally and electrically connected as a leader line on the upper surface of the relay conductive layer 9. The bonding wire 17 is configured to connect structurally and electrically between the relay conductive layer 9 and the receiving circuit 15. A bonding wire 18 is structurally and electrically connected as a lead line on the upper surface of the relay conductive layer 10. The bonding wire 18 is configured to connect structurally and electrically between the relay conductive layer 10 and the receiving circuit 15.

  As shown in FIG. 1, penetrating electrodes 19 and 20 are formed on the upper portion of the coil 6. The through electrode 19 is structurally and electrically connected to the inner end of the spiral coil 6. The through electrode 20 is structurally and electrically connected to the outer end of the spiral coil 6. The through electrode 19 is configured to contact the upper surface of the coil 6 and penetrate the insulator 7 and the soft magnetic body 8 upward from the contact surface.

  The bonding wire 21 is configured to connect structurally and electrically between the through electrode 19 penetrating on the upper surface of the soft magnetic body 8 and the transmission circuit 16. The bonding wire 22 is configured to connect structurally and electrically between the through electrode 20 penetrating on the upper surface of the soft magnetic body 8 and the transmission circuit 16. Such a configuration is accommodated in a resin package (not shown), and is connected from the receiving circuit 15 and the transmitting circuit 16 to various terminals through wiring (not shown). In this manner, the signal transmission integrated circuit device A is configured.

  A manufacturing method of the above structure will be described with reference to FIGS. Note that the configurations of the receiving circuit 15 and the transmitting circuit 16 are not related to the features of the present embodiment, and thus description thereof is omitted.

After the electrical structures of the receiving circuit 15 and the transmitting circuit 16 are formed on a single crystal silicon substrate 1 having a thickness of about several hundred μm by a desired semiconductor process (not shown in FIGS. 4 to 7), FIG. As shown in FIG. 4A, an insulating film 2 such as a silicon oxide film (SiO ₂ ) is formed on the silicon substrate 1. The thickness of the insulating film 2 may be a thickness that can ensure electrical insulation between the magnetic coupling circuit Z and the silicon substrate 1, and is preferably about 500 nm to several μm, for example. In place of the silicon substrate 1, an inorganic substrate made of glass or ceramic, an organic substrate based on epoxy or the like may be used as a support substrate as needed. In this case, it is not necessary to form the insulating film 2. In addition, when the silicon substrate 1 is applied, at least a part or all of the electrical components of the reception circuit 15 and the transmission circuit 16 can be mounted inside by a desired semiconductor process, so that the size can be reduced.

  Next, as shown in FIG. 4B, the relay conductive layers 9 and 10 are formed on the insulating film 2 of the silicon substrate 1 by sputtering, vapor deposition, or plating using a conductive material such as copper, aluminum, or gold. Form along the top surface.

  Next, as shown in FIG. 4C, a silicon oxide film (SiO) or silicon nitride film (SiO 2) is formed on the relay conductive layers 9 and 10 by using a method such as sputtering or CVD (Chemical Vapor Deposition). The insulating films 11 and 12 made of an inorganic film such as SiN) are patterned with a predetermined film thickness of, for example, about 100 to 200 nm so as to cover the relay conductive layers 9 and 10, respectively. The insulating films 11 and 12 may be formed of an organic film such as polyimide by spin coating or vapor deposition instead of the above-described inorganic film. At this time, a hole 11 a penetrating through the upper surface of the relay conductive layer 9 is formed in the insulating film 11, and a hole 12 a penetrating through the upper surface of the relay conductive layer 10 is formed in the insulating film 12. These holes 11a and 12a are provided for embedding the through electrode 14 that contacts the inner end and the outer end of the spiral coil 4 on the receiving circuit 15 side.

  Next, as shown in FIG. 4D, the soft magnetic body 3 is molded, for example, by ferrite so that the outer shape thereof becomes a donut disk shape. In addition, you may form in a disc shape instead of a donut disc shape. As the soft magnetic body 3, instead of ferrite, iron silicon (Fe-Si), iron silicon aluminum alloy (Sendust), nickel iron alloy (permalloy), or amorphous by iron (Fe) group and cobalt (Co) group An alloy may be applied. In this case, it is formed by sputtering, vapor deposition or plating. The soft magnetic body 3 is preferably formed to a thickness that does not cause magnetic saturation when magnetic flux passes (for example, a thickness of about several tens of μm to several hundreds of nm). In order to improve the adhesion between the supporting substrate such as the silicon substrate 1 and the insulating film 2 and the soft magnetic body 3 and to prevent the soft magnetic body 3 from diffusing, titanium ( An adhesion film (not shown) such as Ti) may be formed as a barrier film on the order of several tens of nm. At this time, the through hole 3a penetrating the hole 11a is formed in the soft magnetic body 3, and the through hole 3b penetrating the hole 12a is formed.

  Next, as shown in FIG. 5E, a spiral coil 4 is formed on the upper surface of the soft magnetic body 3 by using a conductive material such as copper, aluminum or gold by sputtering, vapor deposition or plating. Form. Simultaneously with the formation of the coil 4, the through electrodes 13 are embedded in the holes 3a and 11a, and the through electrodes 14 are embedded in the holes 3b and 12a with the same material.

  The coil 4 is wound with, for example, a thickness of several tens of nanometers to several μm and a number of turns of several turns to several tens of turns, and the coil inner diameter portion where the inner end (base end) of the coil is located It is configured to be located at a predetermined ratio (for example, approximately ½) with respect to the (terminal) diameter. Note that the coil 4 only needs to be able to pass magnetic flux between the opposing coils 6 and generate an induced voltage of a predetermined voltage (for example, about several volts) in the coil 4 on the receiving side. It may be formed in the combined shape.

  Next, as shown in FIG. 5F, the coil 4 is formed on the coil 4 so as to cover the coil 4 by using, for example, a silicon oxide film (SiOx) or a silicon nitride film (SiN) as an insulator 5 by sputtering or CVD. Film. When the thickness of the insulator 5 is increased, the withstand voltage is improved. FIG. 5G shows a plan view corresponding to FIG. As shown in FIG. 5G, the outer shape of the insulator 5 is formed into a donut disk shape.

  Next, as shown in FIG. 6H, the spiral coil 6 is formed on the upper surface of the insulator 5 by using, for example, a sputtering method, a vapor deposition method or a plating method using a conductive material such as copper, aluminum or gold. Form. The coil 6 is formed so as to face the coil 4 with the same film thickness as the coil 4 and the same shape. FIG. 6 (j) shows a plan view at the time of forming the coil 6.

  Next, as shown in FIG. 6 (i), an insulator 7 made of an inorganic film such as a silicon oxide film (SiO) or silicon nitride film (SiN) or an organic film such as polyimide is formed on the upper surface and side surfaces of the coil 6. Form along. For example, if the soft magnetic body 8 enters the irregularities between the lines of the coil 6, the magnetic coupling characteristics between the coils 4 and 6 deteriorate, so that the insulator 7 has the irregularities between the lines of the spiral coil 6. This is provided to prevent the coil 4 and 6 from entering, so that the magnetic coupling characteristics between the coils 4 and 6 can be improved. The method for forming the insulator 7 can be the same as the method for forming the insulator 5. At this time, the insulator 7 is formed with a hole 7 a penetrating the inner end upper surface of the spiral coil 6 on the transmission circuit 16 side and a hole 7 b penetrating the outer end upper surface of the coil 6.

  Next, as shown in FIG. 7 (k), the soft magnetic body 8 is formed along the upper and outer surfaces of the insulator 7 and the inner and outer surfaces of the insulator 5. The soft magnetic material 8 is formed by the same method as the soft magnetic material 3 is formed. At this time, a hole 8a penetrating the hole 7a is formed in the soft magnetic body 8, and a hole 8b penetrating the hole 7b is formed.

  Next, as shown in FIG. 7L, a conductive material such as copper, aluminum, or gold is applied, and the through electrodes 19 and 20 are formed by sputtering, vapor deposition, or plating. The through electrodes 19 and 20 are provided to take out the electrodes for electrical connection at the proximal end and the distal end of the transmitting coil 6 to the outside.

  Next, as shown in FIG. 1, a bonding wire 21 is formed between the through electrode 19 and the transmission circuit 16, and a bonding wire 22 is formed between the through electrode 20 and the transmission circuit 16. Further, as shown in FIG. 2, a bonding wire 17 is formed between the relay conductive layer 9 and the receiving circuit 15, and a bonding wire 18 is formed between the relay conductive layer 10 and the receiving circuit 15. Thereafter, the integrated circuit device A can be formed by injection molding with an exterior material such as epoxy resin and packaging so as to cover the whole, but detailed description thereof is omitted.

Next, the electrical configuration will be described with reference to FIG.
FIG. 8 schematically shows an example of the electrical configuration. As shown in FIG. 8, a transmission circuit 16 is configured on the transmission side, and this transmission circuit 16 operates by receiving supply of applied power supply Vdd−Vss. The transmission circuit 16 includes a plurality of buffers 31 to 33 configured in series and a plurality of buffers 34 to 37 connected in parallel to the subsequent stage. When a digital signal is input to the input terminal IN, the buffers 31 to 33 stabilize the rise / fall voltage change of the digital signal. The buffers 34 to 37 are configured to pass a sufficient drive current to the coil 6.

  On the other hand, a receiving circuit 15 is configured on the receiving side, and operates by receiving the supply of the applied power supply Vcc-GND. The receiving circuit 15 shapes the input signal of the coil 4 connected to the input side and outputs a digital signal to the output terminal OUT. As a specific example, the receiving circuit 15 is configured by combining a plurality of resistors R1 to R3 and buffers 38 to 39. The resistor R1 is connected in parallel to the coil 4, and the resistance value is adjusted in advance according to the magnitude of the input signal. Resistors R2 and R3 are connected in series between nodes of power supply Vcc-GND.

  One of the common connection points of the coil 4 and the resistor R 1 is connected to the common connection point between the resistors R 2 and R 3, and the other is connected to the input of the buffer 38. The buffer 38 has a hysteresis characteristic, for example, and its output is connected to the input of the buffer 39. The buffer 39 is configured to output a digital signal to the output terminal OUT.

  FIG. 9 schematically shows a voltage / current waveform by a timing chart, and the operation will be described together with FIG. As shown in FIGS. 8 and 9, when a rectangular wave voltage is applied to the input terminal IN, a positive induced voltage is generated in the coil 4 due to the magnetic coupling action when the input voltage Vin rises. To rise. A predetermined DC voltage (for example, Vcc / 2) divided by the resistors R2 and R3 is superimposed and input to the buffer 38. Since the current flowing through the coil 6 is delayed with respect to the phase of the applied voltage, the current flows with a change having a predetermined degree of increase. This current is determined by the resistance component of the coil 6. For example, a current value can be appropriately maintained by providing a resistance in series with the coil 6.

  The buffer 38 outputs “H” to the output terminal OUT through the buffer 39 at a timing equal to or higher than a predetermined first threshold voltage Vref1 (> the divided voltage Vcc / 2 by the resistors R2 and R3) (shown in FIG. 8). Timing (1)). Thereafter, the induced voltage of the coil 4 gradually decreases according to the inductance component of the coil 4 and returns to the divided voltage, but does not decrease below the divided voltage by the resistors R2 and R3. The “H” state is retained.

  On the other hand, when the input voltage Vin falls, a negative induced voltage is generated in the coil 4 due to the magnetic coupling action, and the input voltage of the buffer 38 drops rapidly. The buffer 38 outputs “L” to the output terminal OUT via the buffer 39 at a timing when this voltage becomes equal to or lower than a predetermined second threshold voltage Vref2 (<the divided voltage by the resistors R2 and R3) (shown in FIG. 8). Timing (2)). Since the current flowing through the coil 6 is delayed with respect to the phase of the applied voltage, it flows with a predetermined decrease.

  Thereafter, the induced voltage of the coil 4 gradually increases and recovers according to the inductance component of the coil 4, but does not reach a voltage exceeding the divided voltage by the resistors R2 and R3. State is maintained.

  Such a signal propagation characteristic of the magnetic coupling circuit Z has a very fast response to a sudden voltage rise / fall at the rising / falling of the input voltage Vin, so that, for example, a signal of a low-speed photocoupler used conventionally is used. Compared with the propagation characteristics, the input / output propagation characteristics can be improved particularly at high frequencies (up to about several hundred MHz). Therefore, the photocoupler can be configured at low cost by the magnetic coupling circuit Z without configuring it with an expensive device having good high-speed response performance.

  FIG. 10 shows a cross-sectional structure of a magnetic coupling circuit that replaces FIG. 1, and FIG. 11 shows a cross-sectional perspective view of the magnetic coupling circuit that replaces FIG. That is, FIG. 10 and FIG. 11 show a modification of the first embodiment. In addition, about the same kind material which has the same function in the component requirement in description of 1st Embodiment, the same code | symbol is attached | subjected, the function description is abbreviate | omitted, and it demonstrates below centering on a different part.

  As shown in FIG. 10, the signal transmission integrated circuit device A2 that replaces the signal transmission integrated circuit device A includes a magnetic coupling circuit Z2 that replaces the magnetic coupling circuit Z. In this modification, the soft magnetic body 8 is not formed along the inner and outer surfaces of the insulators 5 and 7, and the soft magnetic body 8 is not formed on the sides of the coils 4 and 6. Therefore, as shown in FIG. 11, the soft magnetic body 8 is molded into a donut disk shape like the soft magnetic body 3. The other structures are the same as those in FIG.

FIG. 12 shows a magnetic field distribution diagram analyzed by the inventors.
FIG. 12A shows a magnetic field distribution when a soft magnetic material is not provided as a comparison target. FIG. 12B shows the magnetic field distribution in the case where donut disk-type soft magnetic bodies are provided above and below the coil, as shown in FIGS. FIG. 12C shows the magnetic field distribution when the soft magnetic body is provided so as to surround the coil as shown in FIGS.

  When the soft magnetic material is not provided, as shown in the characteristic diagram of FIG. 12A, when the leakage magnetic flux is large and the soft magnetic material 8 is provided only along the upper surface of the insulator 7. As shown in the characteristic diagram of FIG. 12B, the leakage magnetic flux is smaller than the characteristic when the soft magnetic body 8 is not provided. Moreover, as shown in FIG.12 (c), when the soft-magnetic body 8 is provided in cyclic | annular form, it turns out that almost no leakage magnetic flux has generate | occur | produced. That is, by providing the soft magnetic material 8, the magnetic field generated in the coil 6 is efficiently linked to the coil 4 and the magnetic coupling characteristics can be enhanced. In this case, the noise performance can be improved.

FIG. 13 is a characteristic diagram of the magnetic coupling rate analyzed by the inventors.
This FIG. 13 shows the magnetic coupling rate when ferrite is applied as the soft magnetic bodies 3 and 8, and the magnetic coupling rate characteristics can be improved more by providing the ferrite above and below the coils 4 and 6. Furthermore, it has been confirmed that the characteristics of the magnetic coupling rate can be further improved by configuring the coils 4 and 6 to be surrounded by ferrite. In this case, the magnetic coupling rate can be improved regardless of the distance between the coils 4 and 6, and the effect becomes more remarkable as the distance between the coils 4 and 6 is longer.

  As described above, according to the present embodiment, the magnetic coupling circuit Z (Z2) is formed on the silicon substrate 1 with the insulating film 2 interposed between the soft magnetic body 3, the coil 4, the insulator 5, the coil 6, and the soft magnetic circuit. A receiving circuit 15 is electrically connected to the coil 4, a transmitting circuit 16 is electrically connected to the coil 6, and the magnetic coupling circuit Z (Z 2) is a transmitting circuit. 16 and the receiving circuit 15 are integrated in one package and formed in an input / output insulation type. For example, the anti-noise property against external noise is improved while improving the high-speed response performance compared with a circuit using a photocoupler. Can be improved. Moreover, it can be configured practically.

  According to this embodiment, the soft magnetic body 8 is located on the opposite side (upper side) of the coil 6 from the opposite side of the coils 4 and 6, and is disposed along the upper surface of the coil 6. The soft magnetic body 3 is located on the opposite side (lower side) of the coil 4 from the opposite side of the coils 4 and 6 and is disposed along the lower surface of the coil 4. Thereby, the magnetic coupling rate can be increased. Therefore, even if the input current is low, it can be operated with high reliability, and power saving can be achieved.

  In the magnetic coupling circuit Z (Z2), since the insulator 7 is interposed between the coil 6 and the soft magnetic body 8, the material of the soft magnetic body 8 can be prevented from entering between the lines of the coil 6. The magnetic coupling rate between 4 and 6 can be improved.

  In the magnetic coupling circuit Z, since the soft magnetic bodies 3 and 8 are formed so as to surround the inner and outer peripheries of the coils 4 and 6 and the insulators 5 and 7, the magnetic coupling ratio is further increased as compared with the magnetic coupling circuit Z2. Can be improved. In addition, it has a shielding effect against external noise from the outside, and can improve the noise resistance. In addition, although the embodiment in which the soft magnetic body 8 encloses both the inner and outer peripheries of the insulators 5 and 7 is shown, even if it is formed so as to enclose either the inner periphery or the outer periphery. It goes without saying that the effect of can be obtained.

Since the insulator 5 is made of polyimide, it can be easily made thicker than an inorganic film such as a silicon oxide film.
When the magnetic coupling circuits Z and Z2 are formed, the soft magnetic body 3 is formed on the silicon substrate 1 through the insulating film 2, for example, the coil 4 is formed on the soft magnetic body 3, and the insulator 5 is formed on the coil 4. And the coil 6 is formed on the insulator 5 so as to be opposed to the coil 4, and the soft magnetic body 8 is formed on the coil 6 via the insulator 7, for example. , 8 can improve the magnetic coupling rate.

  When the magnetic coupling circuit Z is formed, when the soft magnetic body 8 is formed, since the periphery of the coils 4 and 6 is covered with the soft magnetic body 3 together with the soft magnetic body 3, the magnetic coupling rate can be improved. .

Since the insulator 7 is formed on the coil 6 after forming the coil 6 and before forming the soft magnetic body 8, the soft magnetic body 8 can be prevented from entering between the lines of the coil 6, The magnetic coupling rate between the coils 4 and 6 can be improved.
When the soft magnetic body 8 is formed, since the insulators 5 and 7 are interposed between the soft magnetic body 8 and the coils 4 and 6, the soft magnetic body 8 is interposed between the lines of the coils 4 and 6. Intrusion can be prevented, and the magnetic coupling rate between the coils 4 and 6 can be improved.

(Second Embodiment)
FIG. 14 and FIG. 15 show a second embodiment of the present invention. The difference from the previous embodiment is that the mounting area of the transmission circuit and the reception circuit is changed. Portions having the same functions as those of the above-described embodiment are denoted by the same reference numerals and description thereof is omitted. Hereinafter, different portions will be mainly described.

  FIG. 14 shows an example of the arrangement of receiving circuits. In the integrated circuit device A3 shown in FIG. 14, the mounting area of the receiving circuit 15 is changed as compared with the above-described embodiment. As shown in FIG. 14, the receiving circuit 15 is configured so as to be planarly included in the mounting area of the magnetic coupling circuit Z. Specifically, the receiving circuit 15 is located directly below the coils 4 and 6. For example, the coil 4 and the receiving circuit 15 are electrically connected by through electrodes 41 and 42 extending vertically.

  Then, compared with the above-described embodiment, the mounting area of the integrated circuit device A3 can be reduced in a plane, and the utilization efficiency of the mounting space of the elements can be improved. Further, the length of the electrically conductive layer for connecting the coil 4 and the receiving circuit 15 can be shortened.

  FIG. 15 shows an example of the arrangement form of the transmission circuit. In the integrated circuit device A4 shown in FIG. 15, the mounting area of the transmission circuit 16 is changed as compared with the structure of FIG. As shown in FIG. 15, the transmission circuit 16 is configured so as to be planarly included in the mounting area of the magnetic coupling circuit Z. Specifically, the transmission circuit 16 is located directly above the coils 4 and 6. It is comprised on the upper surface of the soft magnetic body 8 via an insulator 43. Similarly in this case, the mounting area of the integrated circuit device A4 can be reduced in a plane as compared with the above-described embodiment, and the utilization efficiency of the element mounting space can be improved.

  Note that the present invention can be similarly applied to the case where only the transmission circuit 16 is formed so as to be positioned immediately above the coils 4 and 6, and the reception circuit 15 is configured beside the coils 4 and 6. In FIG. 15, the transmission circuit 16 and the reception circuit 15 may be switched and applied.

  As described above, according to the present embodiment, the mounting area of the transmission circuit 16 and / or the receiving circuit 15 is configured to be included in the mounting area of the magnetic coupling circuit Z in a plan view. Thereby, the utilization efficiency of the mounting space of an element improves.

1 is a longitudinal sectional view showing a main part of a signal transmission integrated circuit device according to a first embodiment of the present invention. A plan view showing a main part of a signal transmission integrated circuit device The perspective view which shows the structure of the principal part of an insulated transmission circuit (A)-(d) is process drawing which shows the longitudinal cross-section of the principal part in each manufacturing stage (the 1-the 4) (E)-(f) is process drawing (the 5-the 6) which shows the longitudinal cross-section of the principal part in each manufacturing stage, (g) is a top view shown corresponding to (f) (H)-(i) is process drawing (the 7th-the 8) which shows the longitudinal cross-section of the principal part in each manufacturing stage, (j) is a top view shown corresponding to (h) (K)-(l) is process drawing which shows the longitudinal cross-section of the principal part in each manufacturing stage (the 8-the 10) Electrical configuration diagram of signal transmission integrated circuit device Timing chart FIG. 1 equivalent view showing a modification FIG. 3 equivalent diagram showing a modified example Diagram showing leakage flux Diagram showing correlation between magnetic coupling rate and distance between coils FIG. 1 equivalent view showing a second embodiment of the present invention (part 1) Figure 1 equivalent (part 2)

Explanation of symbols

  In the drawings, A, A2 to A4 are signal transmission integrated circuit devices, Z and Z2 are magnetic coupling circuits, 1 is a silicon substrate (support substrate), 2 is an insulating film, 3 and 8 are soft magnetic materials, and 4 and 6 are coils. 5 and 7 are insulators, 15 is a receiving circuit, and 16 is a transmitting circuit.

Claims (14)

A first soft magnetic body portion formed on a support substrate, a coil-shaped first conductor formed on the first soft magnetic body portion, an insulator formed on the first conductor, and the insulator An insulated transmission circuit comprising a coiled second conductor formed on and opposed to the coiled first conductor, and a second soft magnetic body formed on the second conductor;
A transmission circuit electrically connected to any one of the coiled first and second conductors;
A receiving circuit electrically connected to the other conductor of the conductor to which the transmitting circuit is connected;
A signal transmission integrated circuit device, wherein the insulation transmission circuit, the transmission circuit, and the reception circuit are formed in an input / output insulation type by a circuit integrated in one package.   2. The signal transmission integrated circuit device according to claim 1, wherein the first and second soft magnetic parts are made of ferrite.   At least one of the first and second soft magnetic parts is iron silicon (Fe—Si), iron silicon aluminum (Fe—Si—Al) alloy, nickel iron (Ni—Fe) alloy, iron ( 2. The signal transmission integrated circuit device according to claim 1, wherein the signal transmission integrated circuit device is formed of an Fe) -based or cobalt (Co) -based amorphous alloy.   The said 1st and 2nd soft-magnetic-material part is arrange | positioned on the opposite side to the opposing side between the said 1st and 2nd conductors, The Claim 1 thru | or 3 characterized by the above-mentioned. Signal transmission integrated circuit device.   5. The signal transmission integrated circuit device according to claim 4, further comprising a third soft magnetic body portion formed so as to surround an outer periphery of the coiled first and second conductors.   6. The signal transmission integrated circuit device according to claim 4, further comprising a fourth soft magnetic body portion formed so as to surround the inner peripheries of the coil-shaped first and second conductors.   The signal transmission integrated circuit device according to claim 1, wherein the insulator is made of polyimide.   8. The signal transmission integrated circuit device according to claim 1, wherein at least one of the transmission circuit and the reception circuit is provided in a region immediately below the first conductor. 9.   One of the transmission circuit and the reception circuit is provided in a region immediately below the first conductor, and the other is provided immediately above the second conductor. 2. A signal transmission integrated circuit device according to 1.   10. The signal transmission integrated circuit device according to claim 1, wherein the second soft magnetic body portion is formed with an insulator between the second conductor and the second conductor. 11. A method for manufacturing an insulated transmission circuit of a signal transmission integrated circuit device according to claim 1, comprising:
Forming a first soft magnetic body on a support substrate;
Forming a coiled first conductor on the first soft magnetic part;
Forming a first insulator on the first conductor;
Forming a coiled second conductor on the first insulator so as to be opposed to the coiled first conductor;
Forming a second soft magnetic body portion on the second conductor. A method of manufacturing a signal transmission integrated circuit device, comprising:   The step of forming the second soft magnetic body portion includes forming the first soft magnetic body portion and the first and second conductors so as to cover the periphery of the first and second conductors with the soft magnetic body. 11. A method for manufacturing a signal transmission integrated circuit device according to 11.   12. The method of forming a second insulator on the second conductor before forming the second soft magnetic body after forming the second conductor. Or a method of manufacturing a signal transmission integrated circuit device according to item 12.   12. The step of forming the second soft magnetic body portion includes forming an insulator between the second soft magnetic body portion and the first and second conductors. 14. A method for manufacturing a signal transmission integrated circuit device according to any one of items 13 to 13.

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