Abstract: A high breakdown voltage diode of the present embodiment includes a first conductive semiconductor substrate, a drift layer formed on the first conductive semiconductor substrate and formed of a first conductive semiconductor, a buffer layer formed on the drift layer and formed of a second conductive semiconductor, a second conductive high concentration semiconductor region formed at an upper portion of the buffer layer, a mesa termination unit formed on an end region of a semiconductor apparatus to relax an electric field of the end region when reverse bias is applied between the semiconductor substrate and the buffer layer, and an electric field relaxation region formed at the mesa termination unit and formed of a second conductive semiconductor. A breakdown voltage of a high breakdown voltage diode, in which a pn junction is provided to a semiconductor layer, is increased, and a process yield is improved.

Abstract: A semiconductor rectifier device using an SiC semiconductor at least includes: an anode electrode; an anode area that adjoins the anode electrode and is made of a second conductivity type semiconductor; a drift layer that adjoins the anode area and is made of a first conductivity type semiconductor having a low concentration; a minority carrier absorption layer that adjoins the drift layer and is made of a first conductivity type semiconductor having a higher concentration than that of the drift layer; a high-resistance semiconductor area that adjoins the minority carrier absorption layer, has less thickness than the drift layer and is made of a first conductivity type semiconductor having a concentration lower than that of the minority carrier absorption layer; a cathode contact layer that adjoins the semiconductor area; and a cathode electrode.

Abstract: A gate drive circuit capable of operating at high speed and with low loss without erroneously operating the switching element is provided with a small number of components and a simple and easy circuit configuration. A primary side of a transformer is connected to an output terminal of a low-side gate drive circuit, and a secondary side of the transformer is connected to a gate input side of a high-side switching element. As a positive gate drive voltage is output from the low-side drive circuit, a negative voltage is applied between the gate and source of a high-side switching element, and a gate voltage is suppressed to be equal to or lower than a threshold value. Therefore, the high-side switching element maintains a turn-off state when the low-side switching element is turned on.

Abstract: A semiconductor rectifying device of an embodiment includes a first-conductive-type semiconductor substrate made of a wide bandgap semiconductor, a first-conductive-type semiconductor layer formed on an upper surface of the semiconductor substrate and made of the wide bandgap semiconductor having an impurity concentration lower than that of the semiconductor substrate, a first-conductive-type first semiconductor region formed at a surface of the semiconductor layer and made of the wide bandgap semiconductor, a second-conductive-type second semiconductor region formed around the first semiconductor region and made of the wide bandgap semiconductor, a second-conductive-type third semiconductor region formed around the first semiconductor region and made of the wide bandgap semiconductor having a junction depth deeper than a junction depth of the second semiconductor region, a first electrode that is formed on the first, second, and third semiconductor regions, and a second electrode formed on a lower surface of

Abstract: To realize power supply to each gate drive circuit without using an individual dedicated power supply for each gate drive circuit. A power conversion apparatus includes an individual drive unit that does not require a dedicated power supply, and includes gate drivers connected to switches and interface circuits and a power converter gate drive configured with a common power supply for supplying power to the gate drive unit. Power is supplied from main circuits or a number of common power supplies fewer than that of the number of the switches through one or more power supply terminals included in the interface circuit. Also, the signal can be transmitted by isolation from a signal source to the gate drivers.

Abstract: A power conversion apparatus includes a main circuit with switches, and performs power conversion to generate power to a three-phase AC load from a three- or single-phase AC power supply. Some of the switches are configured, using a bidirectional switch including a normally-on device that is turned OFF when a gate circuit is provided with a positive or negative voltage, and a normally-off device that is turned ON when the gate circuit is provided with a positive or negative voltage, to provide only a specific unidirectional current flow when the gate circuit is not activated, and when the gate circuit is activated, provide and control a bidirectional current flow to direct only in an arbitrary unidirectional way. By providing the power conversion apparatus with a capability of directing back, to a load (motor), any power coming therefrom, the conversion apparatus requires no direct-current link capacitor and a diode clamping circuit.

Abstract: A gate drive circuit capable of operating at high speed and with low loss without erroneously operating the switching element is provided with a small number of components and a simple and easy circuit configuration. A primary side of a transformer is connected to an output terminal of a low-side gate drive circuit, and a secondary side of the transformer is connected to a gate input side of a high-side switching element. As a positive gate drive voltage is output from the low-side drive circuit, a negative voltage is applied between the gate and source of a high-side switching element, and a gate voltage is suppressed to be equal to or lower than a threshold value. Therefore, the high-side switching element maintains a turn-off state when the low-side switching element is turned on.

Abstract: A semiconductor rectifier device using an SiC semiconductor at least includes: an anode electrode; an anode area that adjoins the anode electrode and is made of a second conductivity type semiconductor; a drift layer that adjoins the anode area and is made of a first conductivity type semiconductor having a low concentration; a minority carrier absorption layer that adjoins the drift layer and is made of a first conductivity type semiconductor having a higher concentration than that of the drift layer; a high-resistance semiconductor area that adjoins the minority carrier absorption layer, has less thickness than the drift layer and is made of a first conductivity type semiconductor having a concentration lower than that of the minority carrier absorption layer; a cathode contact layer that adjoins the semiconductor area; and a cathode electrode.

Abstract: A high breakdown voltage diode of the present embodiment includes a first conductive semiconductor substrate, a drift layer formed on the first conductive semiconductor substrate and formed of a first conductive semiconductor, a buffer layer formed on the drift layer and formed of a second conductive semiconductor, a second conductive high concentration semiconductor region formed at an upper portion of the buffer layer, a mesa termination unit formed on an end region of a semiconductor apparatus to relax an electric field of the end region when reverse bias is applied between the semiconductor substrate and the buffer layer, and an electric field relaxation region formed at the mesa termination unit and formed of a second conductive semiconductor. A breakdown voltage of a high breakdown voltage diode, in which a pn junction is provided to a semiconductor layer, is increased, and a process yield is improved.

Abstract: A semiconductor rectifying device of an embodiment includes a first-conductive-type semiconductor substrate made of a wide bandgap semiconductor, a first-conductive-type semiconductor layer formed on an upper surface of the semiconductor substrate and made of the wide bandgap semiconductor having an impurity concentration lower than that of the semiconductor substrate, a first-conductive-type first semiconductor region formed at a surface of the semiconductor layer and made of the wide bandgap semiconductor, a second-conductive-type second semiconductor region formed around the first semiconductor region and made of the wide bandgap semiconductor, a second-conductive-type third semiconductor region formed around the first semiconductor region and made of the wide bandgap semiconductor having a junction depth deeper than a junction depth of the second semiconductor region, a first electrode that is formed on the first, second, and third semiconductor regions, and a second electrode formed on a lower surface of

Abstract: Provided is a power conversion apparatus in which a main circuit is provided with a plurality of switches, and power conversion is performed to generate power for supply to a three-phase AC load from a three- or single-phase AC power supply. At least some of the plurality of switches are configured, using a bidirectional switch including a normally-on device that is turned OFF when a gate circuit is provided with either a positive or negative voltage, and a normally-off device that is turned ON when the gate circuit is provided with either a positive or negative voltage, to provide only a specific unidirectional current flow when the gate circuit is not activated, and when the gate circuit is activated, provide a bidirectional current flow and control the current flow to direct only in an arbitrary unidirectional way.

Abstract: To realize power supply to each gate drive circuit without using an individual dedicated power supply for each gate drive circuit. A power conversion apparatus includes an individual drive unit that does not require a dedicated power supply, and includes gate drivers connected to switches and interface circuits and a power converter gate drive configured with a common power supply for supplying power to the gate drive unit. Power is supplied from main circuits or a number of common power supplies fewer than that of the number of the switches through one or more power supply terminals included in the interface circuit. Also, the signal can be transmitted by isolation from a signal source to the gate drivers.