JP2023006385A - Semiconductor device - Google Patents

Abstract

To provide a semiconductor device that can be easily miniaturized and that can selectively provide a noise elimination function associated with the oscillation of semiconductor devices.SOLUTION: In a semiconductor device that encapsulates at least a switching element and a gate driver of the switching element in an enclosure, at least one of a plurality of magnetic sheets that constitute part of an electric circuit connecting the switching element and the gate driver is configured to be mountable outside the enclosure.SELECTED DRAWING: Figure 1

Description

The present invention relates to a semiconductor device equipped with switching elements. In particular, the present invention relates to a semiconductor device that can be easily miniaturized and that can effectively and selectively provide a function of removing noise accompanying oscillation of a semiconductor element.

2. Description of the Related Art A so-called electronic component built-in module technology is known, which three-dimensionally mounts a semiconductor device with high density by stacking circuit boards on which semiconductor elements are mounted. In particular, when modularizing switching elements such as IGBTs (Insulated Gate Bipolar Transistors) and MOSFETs (Metal-Oxide-Semiconductor Field Effect Transistors), high-frequency switching As control becomes necessary, the noise current that rides on the output current and disturbs the signal waveform in the circuit cannot be ignored, and it is necessary to take necessary measures against the noise current. Noise currents are mainly generated from devices such as driver circuits (ICs) for switching elements, and adversely affect semiconductor elements and the like through electric circuits.

As a countermeasure against such noise currents, for example, a countermeasure is known in which a part of the lead wires forming the electric circuit is covered with a magnetic sheet (for example, a ferrite sheet or the like). Also known is a configuration in which magnetic sheets are laminated and a coil pattern is inserted into the chip to form a chip. More specifically, a ferrite bead is used that is capable of removing disturbance in a signal waveform and adjusting the waveform by passing through a portion of a signal line (for example, a lead wire) of an electric circuit. Ferrite beads eliminate low-frequency noise by reflecting the noise current through the inductor component of the ferrite bead, and high-frequency noise by converting the noise current into heat through the resistance component of the ferrite bead. Remove. Thus, ferrite beads exhibit their functions over a wide frequency band.

Also, it is known that a ferrite bead is composed of a laminate of a plurality of ferrite sheets. Adjacent ones of these multiple ferrite sheets are electrically connected one after another to form a coil with a spiral structure as a whole. A magnetic flux is generated in the ferrite bead when a current flows through it. Since the ferrite bead works as an inductor, the noise current transmitted from the lead wire is removed as heat from the ferrite bead. By increasing the number of ferrite sheets, the coil capacity can be increased, the impedance of the ferrite beads can be easily improved, and the noise removal characteristics can be enhanced.

In addition, since ferrite beads are easy to handle, static electricity and unnecessary radiation noise are removed by arranging ferrite beads 44 on the lands of the internal conductor layers of the multilayer substrate 25, as disclosed in Patent Document 1, for example. configurations are known.

JP 2005-260182 A

In the above-described electronic component built-in module technology, when the inductance is reduced by embedding both the switching element and the gate driver that controls the switching element in the multilayer substrate, noise caused by the gate driver is transmitted to the semiconductor element. Need to minimize impact. However, due to the characteristics of the ferrite bead, the larger the coil capacitance, the better the noise elimination characteristics. Therefore, it is difficult to reduce the size while enhancing the noise elimination characteristics. Therefore, as the miniaturization of the electronic component built-in module progresses, it becomes difficult to install it in an electric circuit. In addition, since ferrite beads always generate heat when noise is removed, the effect on the gate driver cannot be ignored especially in the case of modules with built-in electronic components. Therefore, in the electronic component built-in module, there has been a demand for a structure capable of suppressing noise interference between the gate driver and the switching element while achieving miniaturization while reducing inductance.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a semiconductor device capable of selectively providing a noise removal function while reducing the size of the semiconductor device.

The present inventors have found that the semiconductor device described below can solve the conventional problems described above.
A semiconductor device according to an embodiment of the present invention is a semiconductor device in which at least a switching element and a gate driver for the switching element are included in a housing, and constitutes part of an electric circuit that connects the switching element and the gate driver. The semiconductor device is characterized in that at least one of a plurality of magnetic sheets is configured to be attachable to the outside of the housing.

According to the embodiment of the present invention configured as described above, at least one of the plurality of magnetic sheets constituting a part of the electric circuit connecting the switching element and the gate driver can be attached to the outside of the housing. A plurality of magnetic sheets do not occupy space in the housing, and heat dissipation is facilitated. Furthermore, if noise removal is not required, attachment of the magnetic sheet can be omitted or replaced. Therefore, it becomes possible to easily reduce the size of the semiconductor device, and to effectively and selectively impart a noise removal function including a switching function.

1 is a cross-sectional view of a semiconductor device according to a first embodiment of the present invention; FIG. 3 is an enlarged cross-sectional view around a ferrite bead according to the first embodiment of the present invention; FIG. 1 is a partial circuit diagram of a semiconductor device according to a first embodiment of the invention; FIG. FIG. 4 is a cross-sectional view of a semiconductor device according to a second embodiment of the invention; FIG. 8 is an enlarged cross-sectional view of the periphery of a ferrite bead in a semiconductor device according to a second embodiment of the present invention; 1 is a block configuration diagram showing an example of a control system employing a semiconductor device according to an embodiment of the invention; FIG. 1 is a circuit diagram showing an example of a control system employing a semiconductor device according to an embodiment of the invention; FIG. FIG. 3 is a block configuration diagram showing another example of a control system employing the semiconductor device according to the embodiment of the invention; FIG. 10 is a circuit diagram showing another example of a control system employing the semiconductor device according to the embodiment of the invention;

Several embodiments of the present invention will be described below with reference to the drawings. In addition, the overlapping description is abbreviate|omitted by attaching|subjecting the same code|symbol to the same component.

FIG. 1 is a cross-sectional view showing a first embodiment of a semiconductor device according to the present invention. As shown in FIG. 1 , semiconductor device 110 has first and second semiconductor elements 2 and 3 and gate driver 4 arranged on circuit board 1 , and ferrite bead connecting portion 15 . In this embodiment, the first semiconductor element 2 is an IGBT (Insulated Gate Bipolar Transistor), a MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor), or the like. The second semiconductor element (another semiconductor element) 3, which is a switching element, is an SBD (Schottky Barrier Diode) or a PiN diode, which is a semiconductor component, but is not limited to this. Examples of the second semiconductor element 3 include diodes such as the above-described SBD and PiN diodes. The gate driver 4 is composed of an IC incorporating a drive circuit for controlling the switching operation of the gate electrodes provided in the first semiconductor element 2 . Although not shown, the gate electrode of the first semiconductor element 2 is formed on the upper surface of the first semiconductor element 2 in FIG. The ferrite beads (magnetic sheet) 16 are arranged on the same side as the gate electrode with respect to the thickness direction of the first semiconductor element 2 . Furthermore, the ferrite bead 16 is positioned between the first semiconductor element 2 and the gate driver 4 in plan view. Although not shown, the semiconductor device 110 normally has input/output terminals for power supplied to the gate driver 4 .

The first semiconductor element 2 and the gate driver 4 may be directly connected by the circuit board 1, but in the embodiment of the present invention, the first semiconductor element 2 and the gate driver 4 are separated by the separation portion 5 is formed for a predetermined length. The spacing portion 5 is formed, for example, by partially perforating the circuit board 1 .

The upper surfaces of the first and second semiconductor elements 2 and 3 are connected to the upper wiring layer 8 via vias 7 . The lower surfaces of the first and second semiconductor elements 2 and 3 are connected to a lower wiring layer 10 through vias 9 and further connected to a lower wiring layer 12 through vias 11 . In this specification, the side on which the upper wiring layer 8 is positioned is defined as "upper" with reference to the semiconductor element 2 in FIG. stipulate. Furthermore, the upper wiring layer 8 and the lower wiring layer 12 are connected via a through hole 13 .

Here, the vias 6, 7, 9, 11, the upper wiring layer 8, and the lower wiring layers 10, 12 are mainly made of a material having excellent electrical conductivity and thermal conductivity, such as copper (Cu). . 1, including the spacing portion 5, is filled with an electrically insulating material such as epoxy resin or prepreg. Specifically, after filling the interior of the semiconductor device 110 with an electrical insulating material, a plurality of holes are formed by laser processing or drilling, and the surfaces of these holes are plated with copper to form vias. or molding through holes. By repeating this process, multiple stages of wiring layers and vias are sequentially formed. A housing wall 14 made of a material having excellent thermal conductivity such as copper is provided on the uppermost portion of the semiconductor device 110, and heat dissipation means such as a heat sink is provided on the housing wall 14 as necessary. In the embodiment of the present invention, the housing is defined by the housing wall 14 and the lower wiring layer 12 and has a thickness of about 200 μm to 500 μm, but the present invention is not limited to this dimension.

An electric circuit connecting the first semiconductor element 2 and the gate driver 4 is provided at the height of the housing wall 14 spaced apart above the circuit board 1 in the thickness direction via vias 6a and 6b. It extends to the ferrite bead connecting portion 15 . As shown in the partially enlarged view of FIG. 2, the ferrite bead connecting portion 15 is provided in a state in which the ferrite bead 16 can be electrically connected at both terminals 16a and 16b. That is, the ferrite bead connecting portion 15 is provided so that the electric circuit connecting the first semiconductor element 2 and the gate driver 4 passes through the ferrite bead 16 . In other words, the ferrite bead connecting portion 15 allows the ferrite bead 16 to be attached so as to constitute a part of the electric circuit. The ferrite bead connecting portion 15 is provided at a position exposed from the housing, so that the ferrite bead 16 can be easily connected from the outside of the housing.

As shown in FIG. 1, in the semiconductor device of the present invention, at least a part of the electric circuit between the gate driver 4 and the second semiconductor element 2 is formed outside the housing as a ferrite bead connection portion 15. It has a structure located in With such a structure, the magnetic sheet (ferrite bead) can be attached to the outside of the housing. Note that "at least one of the plurality of magnetic sheets is configured to be attachable to the outside of the housing" means, for example, the gate driver 4 and the second semiconductor element 2, as shown in FIG. A structure in which the terminals of the electric circuit between are positioned outside the housing can be mentioned. The present invention is not limited to the structure shown in FIG. It may be a structure with

Further, in the present invention, the plurality of magnetic sheets preferably form a laminated body, and more preferably form a laminated body having a coil pattern inside. The semiconductor device of FIG. 1 is an example using a so-called ferrite bead, which is a layered body having a coil pattern inside, but the magnetic sheet is not limited to such a ferrite bead. In the semiconductor device shown in FIG. 1, the magnetic sheet constitutes a laminated body (for example, chip ferrite beads) containing a coil pattern inside, so that the noise suppressing effect can be further reduced. Furthermore, since the laminate can be attached to the outside of the housing, it is possible to reduce the adverse effects of the heat generated by the magnetic sheets on the switching elements, etc., without hindering the miniaturization of the semiconductor device, and furthermore, the noise suppression effect described above can be achieved. can play. The above-described effects relating to miniaturization and heat become more pronounced when the magnetic sheets constitute the laminate, that is, when the volume and number of layers of the magnetic sheets are large.

Terminals 16a and 16b of ferrite bead 16 and ferrite bead connection portion 15 can be connected by a known connection method such as soldering. Alternatively, for example, a ferrite bead containing a predetermined number of ferrite sheets may be removed from the ferrite bead connecting portion 15 by melting solder, and instead a ferrite bead containing a larger number of ferrite sheets may be connected. It is also possible to strengthen the function of noise removal. Of course, it is possible to arbitrarily select the noise suppression characteristics of the ferrite beads (material and number of ferrite sheets to be built in). It is also possible to replace it with a ferrite bead with a built-in sheet.

FIG. 3 shows the circuit configuration of the semiconductor device 110 according to this embodiment. FIG. 3 extracts the components shown in FIG. 2, that is, the first semiconductor element 2, the second semiconductor element 3, the gate driver 4, and the ferrite bead 16. Here, a MOSFET is exemplified as the semiconductor element 2, and switching control of the MOSFET 2 is performed by supplying a control signal from the gate driver 4 to the gate electrode G of the MOSFET. The second semiconductor element 3 is an SBD, and functions as a freewheeling diode (FWD) for returning the current of the source electrode S of the MOSFET to the drain electrode D. As the gate resistor (R1) 17a provided between the gate driver 4 and the MOSFET 2, one having an appropriate resistance value is selected in order to achieve a switching speed of the MOSFET 2 suitable for the controlled object (not shown). The resistor (R2) 17b is provided to set the voltage between the gate electrode G and the source electrode S to 0 V when the input signal to the gate electrode G is open.

In the embodiment of the present invention, a ferrite bead 16 can be arranged between the gate driver 4 and the MOSFET 2, more specifically just before the gate electrode G. FIG. That is, the ferrite bead 16 removes the noise current that enters the MOSFET 2 from the gate electrode G, so that the MOSFET 2 is driven with a current that is almost unaffected by noise.

The ferrite bead 16 is composed of a capacitor C, an inductor L, and a resistor R, where C is the parasitic capacitance, L is the inductor of the ferrite bead, and R is the AC resistance (AC core loss) dependent on the ferrite bead. Equivalent to.

In addition, the ferrite bead 16 according to the embodiment of the present invention is formed of one or more ferrite sheets, and the ferrite sheet is wound in a cylindrical shape, or a plurality of ferrite sheets are electrically sequentially wound. They are connected to form a coil having a helical structure as a whole. It is possible to arbitrarily set the values of the capacitor C, the inductor L, and the resistor R by appropriately selecting the material and the number of ferrite sheets. By connecting at least one ferrite sheet onto the ferrite bead connection portion 15, the noise component of the current passing through the ferrite bead 16 is effectively removed. As a result, noise removal for MOSFET2 is performed.

Next, the operation of this embodiment configured as described above will be described in detail.

The embodiment of the present invention adopts a configuration in which the ferrite bead can be connected to the semiconductor device while being exposed from the housing. After fabricating a semiconductor device by housing MOSFETs and gate drivers in a housing in advance, ferrite beads are electrically connected from the outside of the housing, so that the ferrite sheets that constitute the ferrite beads are connected to the MOSFET and the gate driver. It is possible to cover a part of the electric circuit connecting the Therefore, by appropriately selecting and connecting the number of ferrite sheets, materials, and the like that constitute the ferrite bead, the coil structure formed by the ferrite sheets can be set in a desired state. A desired switching operation can be maintained by removing (absorbing) noise that adversely affects the MOSFET and suppressing deterioration of the switching characteristics. From among several ferrite beads with different numbers and materials of built-in ferrite sheets, select the ferrite beads closest to the required switching control of the MOSFET, or change the switching control By appropriately replacing the ferrite beads according to the modification, it is possible to reproduce optimum noise removal characteristics according to the application of the semiconductor device. As a result, even when one module is controlled with different switching characteristics depending on the object to be controlled, the switching characteristics of the MOSFET can be maximized, thereby greatly increasing the versatility of the module. A common module can be applied to all controlled objects, and stable operation can be maintained.

In addition, the heat generated by the noise removal operation of the ferrite bead may adversely affect the gate driver that drives and controls the gate electrode of the MOSFET. On the other hand, as noted above, due to the nature of electrical circuits, the ferrite bead is most preferably placed between the gate driver and the MOSFET. In the embodiment of the present invention, since the ferrite beads can be arranged outside the housing, they can be arranged at any position between the gate driver and the MOSFET on the electric circuit. Intrusion into the interior is avoided as much as possible. That is, while the ferrite beads are arranged physically and electrically close to the MOSFET and the gate driver, the electrical influence on the MOSFET and the thermal influence on the gate driver are suppressed. Therefore, even if the module is miniaturized, it is possible to maintain the performance and reliability of the MOSFET for a long period of time.

The position of the ferrite bead connecting portion 15 is not limited to the position shown in FIG. 1, and can be set at any height outside (upper) or inside (lower) the housing. That is, the entire ferrite bead 16 may be exposed above the housing wall 14 or may be exposed below the housing wall 14 . As long as the ferrite bead 16 can be connected to the ferrite bead connecting portion 15 from the outside of the housing, it is included in the embodiments of the present invention. The position of the ferrite bead connection portion 15 is arbitrarily determined according to the size of the ferrite bead 16, the amount of heat generated, and the like.

Further, in addition to the ferrite bead 16, the gate resistor 17a may also be exposed and mounted above the housing wall 14 in the same manner. As a result, the heat generated from the gate resistor 17a can also be dissipated to the outside of the housing while reducing the influence on the MOSFET.

FIG. 4 is a cross-sectional view of a semiconductor device according to a second embodiment of the invention. As shown in FIG. 4, in the semiconductor device 120, a space (air layer) 18 is provided in a part of the electrically insulating material that fills the space 5 between the first semiconductor element 2 and the gate driver 4. . The space 18 is preferably a space filled with air (dry air), but may be filled with other gases or fluids with low thermal conductivity. Further, the space 18 may be either an open space or a closed space, and in the case of an open space, it may have a conduit leading to the outside of the housing. The space 18 preferably extends in the depth direction of the paper surface of FIG. Especially preferred. Furthermore, the space portion 18 may extend upward toward the resistance connection portion 15 and open toward the outside of the housing.

When manufacturing the space portion 18, the electrical insulating material filled in the space portion 5 is partially removed by etching or the like, or the upper portion of the housing is formed without the ferrite bead 16 attached to the ferrite bead connection portion 15. A known technique such as forming by punching a hole can be used as appropriate.

By providing such a space 18, as indicated by an arrow in FIG. 18 to dissipate to the outside of the housing. Therefore, it is possible to suppress the influence of heat from the first semiconductor element 2 in addition to the influence of heat from the ferrite beads 16 , thereby ensuring a more stable operation of the gate driver 4 .

FIG. 5 is a partially enlarged view schematically showing part of a semiconductor device according to a third embodiment of the invention. In this embodiment, a via 6a is provided directly below the ferrite bead connecting portion 15, and the via 6a is electrically connected to the gate electrode (not shown) of the MOSFET2. That is, the gate electrode of the MOSFET 2, the via 6a, the ferrite bead connecting portion 15, and the terminal 16b of the ferrite bead 16 are arranged substantially linearly in the vertical direction of the paper surface of FIG. That is, in the semiconductor device of FIG. 5, the magnetic sheet (ferrite bead) 16 and the gate electrode overlap each other in plan view.

According to this embodiment having such a configuration, the ferrite bead 16 is arranged immediately before the gate electrode of the MOSFET 2, that is, the electrode to which the control signal from the gate driver 4 is input. Therefore, a clear signal from which noise has been removed by the ferrite beads 16 can be input to the MOSFET 2 at the shortest distance. In particular, by connecting the terminal 16b of the ferrite bead 16 and the gate electrode substantially only with the via 6a, the length of the electric circuit connecting the terminal 16b of the ferrite bead 16 and the gate electrode can be set extremely short. . Thus, a semiconductor device is provided in which the ferrite bead 16 is exposed from the housing and the influence of noise is extremely small.

If the number of wiring layers built into the module is large, a plurality of stages of vias are provided to connect these wiring layers. Even in the case of a multi-level wiring layer in which a plurality of levels of vias are provided, as long as the vias are connected substantially in series, it is included in the embodiment of the present invention. That is, as long as the ferrite bead 16 and the gate electrode of the MOSFET 2 are connected substantially linearly, the circuit length is the shortest regardless of the number of wiring layers and vias in the module. An effect equivalent to that of this embodiment can be obtained.

Each of the semiconductor devices shown in FIGS. 1, 4 and 5 has a configuration in which the ferrite bead 16 is electrically connected to the ferrite bead connecting portions 15a and 15b, but the present invention is not limited to this configuration. For example, the ferrite bead connection portions 15a and 15b may be prepared in a state of being connected by a lead wire, and at least one ferrite sheet may be attached so as to cover the lead wire. That is, the semiconductor devices 100 and 110 in which an electric circuit is formed by lead wires are prepared, and at least one (single-layer) ferrite sheet is wound around the lead wires, which are part of the electric circuit, and attached. As a result, the lead wires are substantially covered with multiple layers of ferrite sheets, and the same effects as in the previous embodiment can be expected. Of course, the lead wires may be covered by winding a ferrite sheet composed of multiple layers around the lead wires. The effect of the present invention can be expected by making it possible to attach at least one of the plurality of ferrite sheets covering part of the electric circuit connecting the semiconductor element and the gate driver to the outside of the housing. In addition, a state in which the ferrite bead connection portions 15a and 15b are connected with lead wires and a ferrite sheet is attached to a part of the lead wires is prepared in advance, and at least one ferrite sheet is attached to the lead wires later. By attaching the ferrite sheet and covering the lead wires, the noise elimination effect may be generated by these ferrite sheets.

A semiconductor device according to an embodiment of the present invention includes a semiconductor element using silicon carbide (SiC), gallium nitride (GaN), gallium oxide (Ga ₂ O ₃ ), etc., which are widely known as semiconductor materials for power semiconductors. Useful if you include In particular, it is extremely useful when including a semiconductor device using corundum-structured gallium oxide (α-Ga ₂ O ₃ ) or β-gallium-structured gallium oxide (β-Ga ₂ O ₃ ) with a high bandgap, It contributes not only to higher density of semiconductor devices but also to improved reliability.

It is of course possible to combine multiple embodiments according to the present invention described above, or to apply some of the constituent elements to other embodiments, and such things also belong to the embodiments of the present invention.

In addition to the first semiconductor element 2 and the second semiconductor element 3, other semiconductor elements may be incorporated in the embodiment of the present invention. Also, other passive components (for example, capacitors, coils, resistors, etc.) may be further incorporated in the semiconductor device. In the embodiment of the present invention, the semiconductor device described above may be used as a submodule, and a plurality of these submodules may be combined to form a module for use.

The semiconductor device according to the embodiment of the present invention described above can be applied to power converters such as inverters and converters in order to exhibit the functions described above. FIG. 6 is a block configuration diagram showing an example of a control system using a semiconductor device according to an embodiment of the present invention, and FIG. 7 is a circuit diagram of the same control system, which is particularly suitable for mounting on an electric vehicle. control system.

As shown in FIG. 6, the control system 500 has a battery (power source) 501, a step-up converter 502, a step-down converter 503, an inverter 504, a motor (to be driven) 505, and a drive control section 506, which are mounted on an electric vehicle. It becomes The battery 501 is composed of a storage battery such as a nickel-metal hydride battery or a lithium-ion battery, and stores electric power by charging at a power supply station or regenerative energy during deceleration, and is necessary for the operation of the running system and electrical system of the electric vehicle. DC voltage can be output. The boost converter 502 is a voltage conversion device equipped with a chopper circuit, for example, and boosts the DC voltage of, for example, 200 V supplied from the battery 501 to, for example, 650 V by switching operation of the chopper circuit, and outputs it to a running system such as a motor. be able to. The step-down converter 503 is also a voltage conversion device equipped with a chopper circuit. It can be output to the electrical system including

Inverter 504 converts the DC voltage supplied from boost converter 502 into a three-phase AC voltage by switching operation, and outputs the three-phase AC voltage to motor 505 . The motor 505 is a three-phase AC motor that constitutes the running system of the electric vehicle, and is rotationally driven by the three-phase AC voltage output from the inverter 504. The rotational driving force is transmitted to the wheels of the electric vehicle via a transmission or the like (not shown). to

On the other hand, various sensors (not shown) are used to measure actual values such as the number of revolutions and torque of the wheels and the amount of depression of the accelerator pedal (acceleration amount) from the running electric vehicle. is entered. At the same time, the output voltage value of inverter 504 is also input to drive control section 506 . The drive control unit 506 has the function of a controller that includes an arithmetic unit such as a CPU (Central Processing Unit) and a data storage unit such as a memory. By outputting it as a feedback signal, the switching operation of the switching element is controlled. As a result, the AC voltage applied to the motor 505 by the inverter 504 is corrected instantaneously, so that the operation control of the electric vehicle can be accurately executed, and safe and comfortable operation of the electric vehicle is realized. It is also possible to control the output voltage to inverter 504 by giving the feedback signal from drive control section 506 to boost converter 502 .

FIG. 7 shows a circuit configuration excluding the step-down converter 503 in FIG. As shown in the figure, the semiconductor device according to the embodiment of the present invention is employed as a Schottky barrier diode in boost converter 502 and inverter 504 for switching control. Boost converter 502 is incorporated in a chopper circuit to perform chopper control, and inverter 504 is incorporated in a switching circuit including IGBTs to perform switching control. By interposing an inductor (such as a coil) in the output of the battery 501, the current is stabilized. It is stabilizing the voltage.

Further, as indicated by the dotted line in FIG. 7, the drive control unit 506 is provided with an operation unit 507 made up of a CPU (Central Processing Unit) and a storage unit 508 made up of a non-volatile memory. The signal input to the drive control unit 506 is supplied to the calculation unit 507, and programmed calculation is performed as necessary to generate a feedback signal for each semiconductor element. Further, the storage unit 508 temporarily holds the calculation result by the calculation unit 507, accumulates physical constants and functions required for drive control in the form of a table, and outputs them to the calculation unit 507 as appropriate. The calculation unit 507 and the storage unit 508 can employ known configurations, and their processing capabilities can be arbitrarily selected.

As shown in FIGS. 6 and 7, in the control system 500, diodes and switching elements such as thyristors, power transistors, IGBTs, MOSFETs, and the like are used for switching operations of the boost converter 502, the step-down converter 503, and the inverter 504. . By using gallium oxide (Ga ₂ O ₃ ), especially corundum-type gallium oxide (α-Ga ₂ O ₃ ), as the material for these semiconductor elements, the switching characteristics are greatly improved. Furthermore, by applying the semiconductor device according to the embodiment of the present invention, extremely good switching characteristics can be expected, and further miniaturization and cost reduction of the control system 500 can be realized. That is, each of the boost converter 502, the step-down converter 503, and the inverter 504 can expect the effect of the present invention. The effect of the present invention can be expected in any of the above.

Note that the above-described control system 500 can apply not only the semiconductor device according to the embodiment of the present invention to the control system of an electric vehicle, but also various devices such as stepping up and stepping down power from a DC power supply and converting power from DC to AC. It can be applied to the control system of the application. It is also possible to use a power source such as a solar cell as the battery.

FIG. 8 is a block configuration diagram showing another example of the control system employing the semiconductor device according to the embodiment of the present invention, and FIG. 9 is a circuit diagram of the same control system, showing infrastructure equipment that operates on power from an AC power supply. This control system is suitable for installation in home appliances, etc.

As shown in FIG. 8, the control system 600 receives power supplied from an external, for example, three-phase AC power source (power source) 601, and includes an AC/DC converter 602, an inverter 604, a motor (to be driven) 605, It has a drive control unit 606, which can be mounted on various devices (described later). The three-phase AC power supply 601 is, for example, a power generation facility of an electric power company (a thermal power plant, a hydroelectric power plant, a geothermal power plant, a nuclear power plant, etc.), and its output is stepped down via a substation and supplied as an AC voltage. be. In addition, for example, in the form of a private power generator or the like, it is installed in a building or in a nearby facility and supplied by a power cable. AC/DC converter 602 is a voltage conversion device that converts AC voltage to DC voltage, and converts AC voltage of 100V or 200V supplied from three-phase AC power supply 601 to a predetermined DC voltage. Specifically, the voltage is converted into a generally used desired DC voltage such as 3.3V, 5V, or 12V. If the object to be driven is a motor, conversion to 12V is performed. A single-phase AC power supply can be used instead of the three-phase AC power supply. In that case, the same system configuration can be achieved by using a single-phase input AC/DC converter.

Inverter 604 converts the DC voltage supplied from AC/DC converter 602 into a three-phase AC voltage by switching operation, and outputs the three-phase AC voltage to motor 605 . The form of the motor 604 differs depending on the object to be controlled, but if the object to be controlled is a train, it drives the wheels; if it is factory equipment, it drives pumps and various power sources; It is a three-phase AC motor, and is rotationally driven by a three-phase AC voltage output from inverter 604, and transmits its rotational driving force to a drive target (not shown).

For example, in home appliances, there are many driven objects that can be directly supplied with the DC voltage output from the AC/DC converter 602 (for example, personal computers, LED lighting equipment, video equipment, audio equipment, etc.). The control system 600 does not require the inverter 604, and as shown in FIG. 8, the DC voltage is supplied from the AC/DC converter 602 to the driven object. In this case, for example, a personal computer is supplied with a DC voltage of 3.3V, and an LED lighting device is supplied with a DC voltage of 5V.

On the other hand, various sensors (not shown) are used to measure actual values such as the rotational speed and torque of the object to be driven, or the temperature and flow rate of the surrounding environment of the object to be driven. At the same time, the output voltage value of inverter 604 is also input to drive control section 606 . Based on these measurement signals, drive control section 606 gives a feedback signal to inverter 604 to control the switching operation of the switching element. As a result, the AC voltage applied to the motor 605 by the inverter 604 is corrected instantaneously, so that the operation control of the object to be driven can be accurately executed, and stable operation of the object to be driven is realized. Further, as described above, when the object to be driven can be driven with a DC voltage, it is possible to feedback-control AC/DC converter 602 instead of feedback to the inverter.

FIG. 9 shows the circuit configuration of FIG. As shown in the figure, the semiconductor device according to the embodiment of the present invention is employed as a Schottky barrier diode in an AC/DC converter 602 and an inverter 604 for switching control. The AC/DC converter 602 uses, for example, a Schottky barrier diode circuit configured in a bridge shape, and performs DC conversion by converting and rectifying the negative voltage component of the input voltage into a positive voltage. Also, the inverter 604 is incorporated in the switching circuit in the IGBT and performs switching control. A capacitor (such as an electrolytic capacitor) is interposed between the AC/DC converter 602 and the inverter 604 to stabilize the voltage.

Further, as indicated by a dotted line in FIG. 9, the drive control unit 606 is provided with an operation unit 607 made up of a CPU and a storage unit 608 made up of a non-volatile memory. The signal input to the drive control unit 606 is supplied to the calculation unit 607, and programmed calculation is performed as necessary to generate a feedback signal for each semiconductor element. Further, the storage unit 608 temporarily holds the result of calculation by the calculation unit 607, accumulates physical constants and functions required for drive control in the form of a table, and outputs them to the calculation unit 607 as appropriate. The calculation unit 607 and the storage unit 608 can employ known configurations, and their processing capabilities can be arbitrarily selected.

In such a control system 600, as in the control system 500 shown in FIGS. 6 and 7, the rectifying operation and switching operation of the AC/DC converter 602 and the inverter 604 are performed by diodes, switching elements such as thyristors and power transistors. , IGBT, MOSFET, etc. are used. Switching characteristics are improved by using gallium oxide (Ga ₂ O ₃ ), particularly corundum type gallium oxide (α-Ga ₂ O ₃ ), as the material for these semiconductor elements. Furthermore, by applying the semiconductor device according to the embodiment of the present invention, extremely good switching characteristics can be expected, and further miniaturization and cost reduction of the control system 600 can be realized. That is, AC/DC converter 602 and inverter 604 can each be expected to have the effect of the present invention. can be expected.

8 and 9 illustrate the motor 605 as an object to be driven, but the object to be driven is not necessarily limited to mechanically operating devices, and can be applied to many devices that require AC voltage. In the control system 600, as long as the drive object is driven by inputting power from an AC power supply, it can be applied to infrastructure equipment (for example, power equipment such as buildings and factories, communication equipment, traffic control equipment, water and sewage treatment). Equipment, system equipment, labor-saving equipment, trains, etc.) and home appliances (e.g., refrigerators, washing machines, personal computers, LED lighting equipment, video equipment, audio equipment, etc.). can.

1 circuit board
2 Semiconductor device (switching device)
3 Semiconductor device
4 gate drivers
5 Separation part
6a, 6b, 7, 9, 11 Via
13 through hole
15 Ferrite bead connection
16 Ferrite beads (magnetic sheet)
18 Space (air layer)
110, 120 Semiconductor equipment
500 control system
501 battery (power supply)
502 Boost Converter
503 Buck Converter
504 Inverter
505 motor (driven)
506 drive controller
507 Calculator
508 Memory
600 control system
601 Three-phase AC power supply (power supply)
602 AC/DC converter
604 Inverter
605 motor (driven)
606 drive controller
607 Calculator
608 memory

Claims (13)

In a semiconductor device containing at least a switching element and a gate driver for the switching element in a housing, at least one of a plurality of magnetic sheets forming a part of an electric circuit connecting the switching element and the gate driver is provided in the housing. A semiconductor device, characterized in that it is configured to be mountable on the outside of a device. A part of an electric circuit that connects the gate driver and the switching element is provided in a state exposed from the housing, and the at least one magnetic sheet is configured to be attachable to the exposed electric circuit. The semiconductor device according to claim 1, characterized by: A hole is provided in the housing, a part of an electric circuit connecting the at least one magnetic sheet and the switching element is exposed from the hole, and the at least one magnetic sheet can be attached to the exposed electric circuit. 2. The semiconductor device according to claim 1, wherein the semiconductor device is 2. The semiconductor device according to claim 1, wherein said switching element and said gate driver are arranged with a separation portion interposed therebetween, and said separation portion is filled with an electrical insulating material. 2. The semiconductor device according to claim 1, wherein said switching element and said gate driver are arranged with a separation portion therebetween, and said separation portion has an air layer. 2. The semiconductor device according to claim 1, further comprising a substrate on which said switching element and said gate driver are mounted, wherein said at least one magnetic sheet can be arranged at positions separated from each other in the thickness direction of said substrate. 2. The semiconductor according to claim 1, wherein said switching element includes at least a gate electrode, and said at least one magnetic sheet can be arranged on the same side as said gate electrode in the thickness direction of said switching element. Device. 2. The semiconductor device according to claim 1, wherein said at least one magnetic sheet can be arranged between said switching element and said gate driver in plan view. 2. The semiconductor device according to claim 1, wherein said at least one magnetic sheet can be arranged at a position at least partially overlapping said switching element in plan view. The plurality of magnetic sheets form a laminate including a coil pattern inside, and the electric circuit is electrically connected by mounting the laminate on the outside of the housing. Item 2. The semiconductor device according to item 1. 11. The semiconductor device according to claim 10, wherein said laminate is detachably attached to the outside of said housing. A power converter using the semiconductor device according to claim 1 . A control system using the semiconductor device according to claim 1 .

Images