Abstract: A service life diagnostic device includes a Vce amplifier, a Vee amplifier, and a service life diagnostic unit. The Vce amplifier measures a voltage between a collector main terminal connected to a collector electrode of a semiconductor element mounted on a semiconductor device, and an emitter main terminal connected to an emitter electrode of the semiconductor element. The Vee amplifier measures a voltage Vee between the emitter main terminal and an emitter reference terminal connected to the emitter electrode. The service life diagnostic unit diagnoses a service life of the semiconductor device using a correlation value between a temporal change of the voltage Vce and a temporal change of the voltage Vee.

Abstract: A semiconductor device is subjected to ON/OFF control by controlling a gate voltage according to a drive control signal (Ssw). In a turn-on operation for charging a gate in response to transition of drive control signal (Ssw) from a first level (0) to a second level (1), a drive signal (Sdr) is set to first level (0) to discharge the gate at a first time (t1) after end of a Miller period (200) of a gate voltage (Vg), thereby providing a voltage drop period (210) in which gate voltage (Vg) temporarily drops. At a second time (t2), drive signal (Sdr) is again set to second level (1) to start charging the gate.

Abstract: A deteriorated section identifying unit refers to correspondence information that defines a deteriorated section of a plurality of bonding sections to the emitter electrode surface to which the first bonding wires are connected, for a combination of temporal change of a first voltage that is a difference between a potential at a collector main terminal and a potential at the emitter main terminal and temporal change of a second voltage that is a difference between a potential at the emitter reference terminal and a potential at the emitter main terminal, and identifies the deteriorated section corresponding to a combination of temporal change of the first voltage measured by a first voltage measuring circuit and temporal change of the second voltage measured by a second voltage measuring circuit.

Abstract: A direct-current power supply applies a DC voltage to test semiconductor devices. A current detection unit detects a leakage current of a test circuit in which test semiconductor devices are included. A measuring instrument records a pulse waveform of the leakage current. An analyzer analyzes reliability of test semiconductor devices included in the test circuit based on the recorded pulse waveform.

Abstract: In this semiconductor device, an emitter electrode of a power semiconductor element includes a first sub-electrode provided in a region including a central portion of a front surface of a semiconductor substrate and a second sub-electrode provided in a region not including the central portion of the front surface of the semiconductor substrate. A first bonding wire connects the first sub-electrode and an emitter terminal. A second bonding wire connects the second sub-electrode and the emitter terminal. First and second voltage detectors detect voltages between the emitter terminal and the first and second sub-electrodes, respectively. It is possible to separately detect degradation of both the first bonding wire that degrades in an early period and the second bonding wire that degrades in a terminal period.

Abstract: A deteriorated section identifying unit refers to correspondence information that defines a deteriorated section of a plurality of bonding sections to the emitter electrode surface to which the first bonding wires are connected, for a combination of temporal change of a first voltage that is a difference between a potential at a collector main terminal and a potential at the emitter main terminal and temporal change of a second voltage that is a difference between a potential at the emitter reference terminal and a potential at the emitter main terminal, and identifies the deteriorated section corresponding to a combination of temporal change of the first voltage measured by a first voltage measuring circuit and temporal change of the second voltage measured by a second voltage measuring circuit.

Abstract: In a short circuit protection circuit, a first gate resistor is connected between a first output node of a gate driver and a first gate terminal. A first real-time control circuit operates to decrease a potential of the first gate terminal when the first real-time control circuit detects that a short circuit current passes through a first semiconductor switching element. The operation monitoring circuit includes a differential voltage circuit configured to output a potential difference between a potential proportional to a potential difference across the first gate resistor and the potential of a first power supply. The operation monitoring circuit monitors, based on an output of the differential voltage circuit, whether the first real-time control circuit is in operation.

Abstract: A direct-current power supply applies a DC voltage to test semiconductor devices. A current detection unit detects a leakage current of a test circuit in which test semiconductor devices are included. A measuring instrument records a pulse waveform of the leakage current. An analyzer analyzes reliability of test semiconductor devices included in the test circuit based on the recorded pulse waveform.

Abstract: In a short circuit protection circuit, a first gate resistor is connected between a first output node of a gate driver and a first gate terminal. A first real-time control circuit operates to decrease a potential of the first gate terminal when the first real-time control circuit detects that a short circuit current passes through a first semiconductor switching element. The operation monitoring circuit includes a differential voltage circuit configured to output a potential difference between a potential proportional to a potential difference across the first gate resistor and the potential of a first power supply. The operation monitoring circuit monitors, based on an output of the differential voltage circuit, whether the first real-time control circuit is in operation.

Abstract: Turn-on and turn-off of a semiconductor device are controlled through control of a gate voltage in accordance with a driving control signal. At a first time after a start of a Miller period of a gate voltage in driving a gate of the semiconductor device in accordance with the driving control signal, a driving signal is changed from “1” to “0” to thereby make a gate driving ability temporarily lower than the gate driving ability during a period from a starting time of the turn-on operation to the first time. Further, at a second time corresponding to an end of the Miller period, the driving signal is changed from “0” to “1” to thereby increase the gate driving ability.

Abstract: A power switching apparatus includes a plurality of semiconductor switching devices connected in parallel with each other and a plurality of balance resistor units. The plurality of balance resistor units each have one end connected to a control electrode of an associated semiconductor switching device and the other end to which a common control signal is input. Each balance resistor unit is configured to have a resistance value switched between different values depending on whether the plurality of semiconductor switching devices are turned on or turned off in accordance with the control signal.

Abstract: Turn-on and turn-off of a semiconductor device are controlled through control of a gate voltage in accordance with a driving control signal. At a first time after a start of a Miller period of a gate voltage in driving a gate of the semiconductor device in accordance with the driving control signal, a driving signal is changed from “1” to “0” to thereby make a gate driving ability temporarily lower than the gate driving ability during a period from a starting time of the turn-on operation to the first time. Further, at a second time corresponding to an end of the Miller period, the driving signal is changed from “0” to “1” to thereby increase the gate driving ability.

Abstract: A power switching apparatus includes a plurality of semiconductor switching devices connected in parallel with each other and a plurality of balance resistor units. The plurality of balance resistor units each have one end connected to a control electrode of an associated semiconductor switching device and the other end to which a common control signal is input. Each balance resistor unit is configured to have a resistance value switched between different values depending on whether the plurality of semiconductor switching devices are turned on or turned off in accordance with the control signal.

Abstract: A thin film forming apparatus using laser includes a chamber (1), a target (5) placed therein, a laser light source (10) for emitting laser beam to target (5), and a substrate holder (3). When target (5) is irradiated with laser beam (16), a plume (15) is generated, and materials included in plume (15) are deposited on the surface of a substrate (2) held by substrate holder (3). The laser beam emitted from laser light source (10) has its cross section shaped to a desired shape when passed through a shielding plate (4804), for example, so that the surface of the target (5) is irradiated with the beam having uniform light intensity distribution. Therefore, a plume (15) having uniform density distribution of active particles is generated, and therefore a thin film of high quality can be formed over a wide area with uniform film quality, without damaging the substrate.

Abstract: A thin film forming apparatus using laser includes a chamber (1), a target (5) placed therein, a laser light source (10) for emitting laser beam to target (5), and a substrate holder (3). When target (5) is irradiated with laser beam (16), a plume (15) is generated, and materials included in plume (15) are deposited on the surface of a substrate (2) held by substrate holder (3). The laser beam emitted from laser light source (10) has its cross section shaped to a desired shape when passed through a shielding plate (4804), for example, so that the surface of the target (5) is irradiated with the beam having uniform light intensity distribution. Therefore, a plume (15) having uniform density distribution of active particles is generated, and therefore a thin film of high quality can be formed over a wide area with uniform film quality, without damaging the substrate.

Abstract: A thin film forming apparatus using laser includes a chamber (1), a target (5) placed therein, a laser light source (10) for emitting laser beam to target (5), and a substrate holder (3). When target (5) is irradiated with laser beam (16), a plume (15) is generated, and materials included in plume (15) are deposited on the surface of a substrate (2) held by substrate holder (3). The laser beam emitted from laser light source (10) has its cross section shaped to a desired shape when passed through a shielding plate (4804), for example, so that the surface of the target (5) is irradiated with the beam having uniform light intensity distribution. Therefore, a plume (15) having uniform density distribution of active particles is generated, and therefore a thin film of high quality can be formed over a wide area with uniform film quality, without damaging the substrate.

Abstract: A heat and oxidation resistive high strength material utilized in structural body parts subject to bleaching in high temperature/oxidative atmosphere, the body structure of a space vehicle, a combustor, the combustor for a gas turbine, a turbine blade, and a turbine nozzle, is presented. A method for producing this heat and oxidation resistive high strength material is also explained.

Abstract: A novel circuit board in which circuit portions including pad portions, through-hole portions and conductors are formed, at least at the pad portions and the through-hole portions of the circuit, in the vacant portions defined by a cured photopolymeric resin composition and the vacant portions are plated with electroless copper. When only the pad portions and through-hole portions are plated with electroless copper, the conductors are all covered with the resin composition, thereby enabling fears of mechanical and chemical damages to be eliminated. When all the circuit portions are plated with electroless copper, the amount of copper required can be considerably reduced.