Abstract: In sonic examples, a method includes pre-stressing a flange, heating the flange to a die-attach temperature, and attaching a die to the flange at the die-attach temperature using a die-attach material. In some examples, the flange includes a metal material, the die-attach temperature may be at least two hundred degrees Celsius, and the die-attach material may include solder and/or an adhesive. In some examples, the method includes cooling the semiconductor die and metal flange to a room temperature after attaching the semiconductor die to the metal flange at the die-attach temperature using a die-attach material.

Abstract: A High Mobility Electron Transistor (HEMT) and a capacitor co-formed on an integrated circuit (IC) share at least one structural feature, thereby tightly integrating the two components. In one embodiment, the shared feature may be a 2DEG channel of the HEMT, which also functions in lieu of a base metal layer of a conventional capacitor. In another embodiment, a dialectic layer of the capacitor may be formed in a passivation step of forming the HEMT. In another embodiment, a metal contact of the HEMT (e.g., source, gate, or drain contact) comprises a metal layer or contact of the capacitor. In these embodiments, one or more processing steps required to form a conventional capacitor are obviated by exploiting one or more processing steps already performed in fabrication of the HEMT.

Abstract: An electronic package houses one or more RF amplifier circuits. At least one of an input or output impedance matching network integrated on the package and electrically coupled to the gate or drain bias voltage connection, respectively, of an amplifier circuit, includes a multi-stage decoupling network. Each multi-stage decoupling network includes two or more decoupling stages. Each decoupling stage of the multi-stage decoupling network includes a resistance, inductance, and capacitance, and is configured to reduce impedance seen by the amplifier circuit at a different frequency below an operating band of the amplifier circuit. Bias voltage connections to the impedance matching circuits may be shared, and may be connected anywhere along the multi-stage decoupling network.

Abstract: In an asymmetric Doherty amplifier circuit, one or more shunt reactive components are added to at least one side of an impedance inverter connecting the amplifier outputs, to reduce a capacitance imbalance between the two amplifiers caused by their different parasitic capacitances. This enables the (adjusted) parasitic capacitances to be incorporated into a quarter-wavelength transmission line, having a 90-degree phase shift, for the impedance inverter. In one embodiment, a shunt inductance is connected between the impedance inverter, on the side of the larger amplifier, and RF signal ground. The inductance is sized to resonate away substantially the excess parasitic capacitance of the larger amplifier. In another embodiment, a shunt capacitor is connected on the side of the smaller amplifier, thus raising its total capacitance to substantially equal the parasitic capacitance of the larger amplifier.

Abstract: Power switching devices include a semiconductor layer structure that has an active region and an inactive region. The active region includes a plurality of unit cells and the inactive region includes a field insulating layer on the semiconductor layer structure and a gate bond pad on the field insulating layer opposite the semiconductor layer structure. A gate insulating pattern is provided on the semiconductor layer structure between the active region and the field insulating layer, and at least one source/drain contact is provided on the semiconductor layer structure between the gate insulating pattern and the field insulating layer.

Abstract: A process and system for testing includes: arranging devices in a temperature-controlled environment; applying a negative gate bias voltage (Vgs) to the devices; applying a drain voltage (Vds) to the devices; measuring currents and/or voltages of the devices to generate device test data; determining a failure of one or more of the devices based on the device test data generated from the device currents and/or the voltages to generate failure data; and outputting the failure data for the of devices.

Abstract: The present disclosure relates to a power module that has a housing with an interior chamber and a plurality of switch modules interconnected to facilitate switching power to a load. Each of the plurality of switch modules comprises at least one transistor and at least one diode mounted within the interior chamber and both the at least one transistor and the at least one diode are majority carrier devices, are formed of a wide bandgap material system, or both. The switching modules may be arranged in virtually any fashion depending on the application. For example, the switching modules may be arranged in a six-pack, full H-bridge, half H-bridge, single switch or the like.

Abstract: A transistor semiconductor die includes a drift layer, a first dielectric layer, a first metallization layer, a second dielectric layer, a second metallization layer, a first plurality of electrodes, and a second plurality of electrodes. The first dielectric layer is over the drift layer. The first metallization layer is over the first dielectric layer such that at least a portion of the first metallization layer provides a first contact pad. The second dielectric layer is over the first metallization layer. The second metallization layer is over the second dielectric layer such that at least a portion of the second metallization layer provides a second contact pad and the second metallization layer at least partially overlaps the first metallization layer. The transistor semiconductor die is configured to selectively conduct current between the first contact pad and a third contact pad based on signals provided at the second contact pad.

Abstract: A power MOSFET includes a silicon carbide drift region having a first conductivity type, first and second well regions located in upper portions of the silicon carbide drift region that are doped with second conductivity dopants, and a channel region in a side portion of the first well region, an upper portion of the channel region having the first conductivity type, wherein a depth of the first well region is at least 1.5 microns and the depth of the first well region exceeds a distance between the first and second well regions.

Abstract: A semiconductor device package includes a package substrate having a die attach region, a silicon carbide (SiC) substrate having a first surface including a semiconductor device layer thereon and a second surface that is opposite the first surface, and a die attach metal stack. The die attach metal stack includes a sputtered die attach material layer that attaches the second surface of the SiC substrate to the die attach region of the package substrate, where the sputtered die attach material layer comprises a void percent of about 15% or less. The sputtered die attach material layer may be formed using a sputter gas including at least one of krypton (Kr), xenon (Xe), or radon (Rn). The die attach metal stack may further include a metal interlayer that prevent contacts with a first barrier metal layer during a phase transition of the die attach material layer.

Abstract: Support circuitry for a power transistor includes a feedback switching element and switching control circuitry. The feedback switching element is coupled between a Kelvin connection node and a second power switching node. The switching control circuitry is configured to cause the feedback switching element to couple the Kelvin connection node to the second power switching node after the power transistor is switched from a blocking mode of operation to a conduction mode of operation and cause the feedback switching element to isolate the Kelvin connection node from the second power switching node before the power transistor is switched from the conduction mode of operation to the blocking mode of operation.

Abstract: A process for manufacturing an electronic component having attaches includes providing a first component having a first attach, forming trenches on a portion of the first attach with a laser to form a solder stop, and providing a second component comprising a second attach. The process further includes providing solder between the first attach and the second attach to form a connection between the first component and the second component, where the trenches contain the solder to a usable area. A device produced by the process is disclosed as well.

Abstract: In a transistor formed on a semiconductor die mounted on a substrate, where the transistor output is connected to a circuit on the substrate, a bond pad electrically connected to a transistor drain finger manifold extends less than the full length of the manifold. By controlling the length of the bond pad, the parasitic capacitance it contributes may be controlled. In applications such as a Doherty amplifier, this parasitic capacitance forms part of the quarter-wave transmission line of an impedance inverter, and hence directly impacts amplifier performance. In particular, by reducing the parasitic capacitance contribution from transistor output bond pads, the bandwidth of a Doherty amplifier circuit may be improved. At GHz frequencies and with state of the art transistor device feature sizes, concerns about phase mismatch between drain finger outputs are largely moot.

Abstract: In a Doherty amplifier, outputs of first (main) and second (peak) transistors are connected by a combined impedance inverter and harmonic termination circuit. The harmonic termination circuit incorporates a predetermined part of the impedance inverter, and provides a harmonic load impedance at a targeted harmonic frequency (e.g., the second harmonic). Control of the amplitude and phase of the harmonic load impedance facilitates shaping of the drain current and voltage waveforms to maximize gain and efficiency, while maintaining a good load modulation at a fundamental frequency. Particularly for Group III nitride semiconductors, such as GaN, both harmonic control and output impedance matching circuits may be eliminated from the outputs of each transistor. The combined impedance inverter and harmonic termination circuit reduces the amplifier circuit footprint, for high integration and low power consumption.

Abstract: A metal-oxide-semiconductor field-effect transistor includes a wide bandgap substrate, a wide bandgap drift layer over the substrate, a number of junction implants in the drift layer, and a JFET region between the junction implants. The JFET region is defined by a JFET gap, which is the distance between adjacent ones of the junction implants. The JFET gap is not uniform throughout the MOSFET device. The JFET region is separated into a first JFET sub-region and a second JFET sub-region, such that a doping concentration in the first JFET sub-region is different from a doping concentration in the second JFET sub-region.

Abstract: Semiconductor devices include a silicon carbide drift region having an upper portion and a lower portion. A first contact is on the upper portion of the drift region and a second contact is on the lower portion of the drift region. The drift region includes a superjunction structure that includes a p-n junction that is formed at an angle of between 10° and 30° from a plane that is normal to a top surface of the drift region. The p-n junction extends within +/?1.5° of a crystallographic axis of the silicon carbide material forming the drift region.

Abstract: A transistor includes a semiconductor layer structure, a source electrode and a drain electrode on the semiconductor layer structure, a gate on a surface of the semiconductor layer structure between the source electrode and the drain electrode, and a field plate. The field plate includes a first portion adjacent the gate and a second portion adjacent the source or drain electrode. The second portion of the field plate is farther from the surface of the semiconductor layer structure than the first portion of the field plate, and is closer to the surface of the semiconductor layer structure than an extended portion of the gate. Related devices and fabrication methods are also discussed.

Abstract: A multi-cell transistor includes a semiconductor structure, a plurality of unit cell transistors that are electrically connected in parallel, each unit cell transistor extending in a first direction in the semiconductor structure, wherein the unit cell transistors are spaced apart from each other along a second direction, and an isolation structure that is positioned between a first group of the unit cell transistors and a second group of the unit cell transistors and that extends above the semiconductor structure.

Abstract: A power module includes a plurality of power semiconductor devices. The plurality of power semiconductor devices includes an insulated gate bipolar transistor (IGBT) and a metal-oxide-semiconductor field-effect transistor (MOSFET) coupled in parallel between a first power switching terminal and a second power switching terminal. The IGBT and the MOSFET are silicon carbide devices. By providing the IGBT and the MOSFET together, a tradeoff between forward conduction current and reverse conduction current of the power module, the efficiency, and the specific current rating of the power module may be improved. Further, providing the IGBT and the MOSFET as silicon carbide devices may significantly improve the performance of the power module.

Abstract: Silicon carbide (SiC) wafers and related methods are disclosed that include intentional or imposed wafer shapes that are configured to reduce manufacturing problems associated with deformation, bowing, or sagging of such wafers due to gravitational forces or from preexisting crystal stress. Intentional or imposed wafer shapes may comprise SiC wafers with a relaxed positive bow from silicon faces thereof. In this manner, effects associated with deformation, bowing, or sagging for SiC wafers, and in particular for large area SiC wafers, may be reduced. Related methods for providing SiC wafers with relaxed positive bow are disclosed that provide reduced kerf losses of bulk crystalline material. Such methods may include laser-assisted separation of SiC wafers from bulk crystalline material.