Multiple wide bandgap semiconductor wafers, each having active circuitry and an epitaxially formed backside drain contact layer, may be constructed from a single bulk semiconductor substrate by: forming foundational layers on the top of the bulk substrate via epitaxy; forming active circuitry atop the foundational layers; laser treating the backside of the bulk substrate to create a cleave line in one of the foundational layers; and exfoliating a semiconductor wafer from the bulk substrate, where the exfoliated semiconductor wafer contains the active circuits and at least a portion of the foundational layers. Wafers containing the foundational layers without complete active devices may be produced in a similar manner. The foundational layers may comprise a drain contact layer and a drift layer, and may additionally include a buffer layer between the drain contact layer and the drift layer.

An electronics assembly includes a semiconductor device having a first device surface and at least one device conductive layer disposed directly thereon. A cooling structure coupled to the semiconductor device includes a manifold layer, a microchannel layer bonded to the manifold layer, at least one planar side cooling structure, and one or more cooling structure conductive layers. The manifold layer includes a fluid inlet and a fluid outlet and defines a first cooling structure surface. The microchannel layer comprises at least one microchannel fluidly coupled to the fluid inlet and the fluid outlet and defines a second cooling structure surface opposite from the first cooling structure surface. The planar side cooling structure surface is transverse to the first and the second cooling structure surfaces. The cooling structure conductive layers are disposed directly on the first cooling structure surface, the second cooling structure surface, and the planar side cooling structure surface.

Multiple wide bandgap semiconductor wafers, each having active circuitry and an epitaxially formed backside drain contact layer, may be constructed from a single bulk semiconductor substrate by: forming foundational layers on the top of the bulk substrate via epitaxy; forming active circuitry atop the foundational layers; laser treating the backside of the bulk substrate to create a cleave line in one of the foundational layers; and exfoliating a semiconductor wafer from the bulk substrate, where the exfoliated semiconductor wafer contains the active circuits and at least a portion of the foundational layers. Wafers containing the foundational layers without complete active devices may be produced in a similar manner. The foundational layers may comprise a drain contact layer and a drift layer, and may additionally include a buffer layer between the drain contact layer and the drift layer.

An electronics assembly comprises a semiconductor device having a first device surface and at least one device conductive layer disposed on the first device surface. A cooling structure is coupled to the semiconductor device. The cooling structure comprises a first cooling structure surface and a second cooling structure surface. The second cooling structure surface is opposite from the first cooling structure surface and the first cooling structure surface is coupled to the semiconductor device. One side cooling structure surface is transverse to the respective first and second cooling structure surface. The one side electrode is disposed on the at least one side cooling structure surface in which the at least one side electrode is electrically coupled to the at least one device conductive layer. The cooling structure includes a fluid inlet for receiving a cooling fluid and a fluid outlet for removing the cooling fluid from the cooling structure.

A multilayer composite bonding material for transient liquid phase bonding a semiconductor device to a metal substrate includes thermal stress compensation layers sandwiched between a pair of bonding layers. The thermal stress compensation layers may include a core layer with a first stiffness sandwiched between a pair of outer layers with a second stiffness that is different than the first stiffness such that a graded stiffness extends across a thickness of the thermal stress compensation layers. The thermal stress compensation layers have a melting point above a sintering temperature and the bonding layers have a melting point below the sintering temperature. The graded stiffness across the thickness of the thermal stress compensation layers compensates for thermal contraction mismatch between the semiconductor device and the metal substrate during cooling from the sintering temperature to ambient temperature.

A multilayer composite bonding material for transient liquid phase bonding a semiconductor device to a metal substrate includes thermal stress compensation layers sandwiched between a pair of bonding layers. The thermal stress compensation layers may include a core layer with a first stiffness sandwiched between a pair of outer layers with a second stiffness that is different than the first stiffness such that a graded stiffness extends across a thickness of the thermal stress compensation layers. The thermal stress compensation layers have a melting point above a sintering temperature and the bonding layers have a melting point below the sintering temperature. The graded stiffness across the thickness of the thermal stress compensation layers compensates for thermal contraction mismatch between the semiconductor device and the metal substrate during cooling from the sintering temperature to ambient temperature.

A transient liquid phase (TLP) composition includes a plurality of first high melting temperature (HMT) particles, a plurality of second HMT particles, and a plurality of low melting temperature (LMT) particles. Each of the plurality of first HMT particles have a core-shell structure with a core formed from a first high HMT material and a shell formed from a second HMT material that is different than the first HMT material. The plurality of second HMT particles are formed from a third HMT material that is different than the second HMT material and the plurality of LMT particles are formed from a LMT material. The LMT particles have a melting temperature less than a TLP sintering temperature of the TLP composition and the first, second, and third HMT materials have a melting point greater than the TLP sintering temperature.

A power electronics assembly includes a semiconductor device stack having a wide bandgap semiconductor device, a semiconductor cooling chip thermally coupled to the wide bandgap semiconductor device, and a first electrode electrically coupled to the wide bandgap semiconductor device and positioned between the wide bandgap semiconductor device and the semiconductor cooling chip. The semiconductor cooling chip is positioned between a substrate layer and the wide bandgap semiconductor device. The substrate layer includes a substrate inlet port and a substrate outlet port. An integrated fluid channel system extends between the substrate inlet port and the substrate outlet port and includes a substrate fluid inlet channel extending from the substrate inlet port into the substrate layer, a substrate fluid outlet channel extending from the substrate outlet port into the substrate layer, and one or more cooling chip fluid channels extending into the semiconductor cooling chip.

A power electronics assembly includes a semiconductor device stack having a wide bandgap semiconductor device, a semiconductor cooling chip thermally coupled to the wide bandgap semiconductor device, and a first electrode electrically coupled to the wide bandgap semiconductor device and positioned between the wide bandgap semiconductor device and the semiconductor cooling chip. The semiconductor cooling chip is positioned between a substrate layer and the wide bandgap semiconductor device. The substrate layer includes a substrate inlet port and a substrate outlet port. An integrated fluid channel system extends between the substrate inlet port and the substrate outlet port and includes a substrate fluid inlet channel extending from the substrate inlet port into the substrate layer, a substrate fluid outlet channel extending from the substrate outlet port into the substrate layer, and one or more cooling chip fluid channels extending into the semiconductor cooling chip.

A multilayer composite bonding material for transient liquid phase bonding a semiconductor device to a metal substrate includes thermal stress compensation layers sandwiched between a pair of bonding layers. The thermal stress compensation layers may include a core layer with a first stiffness sandwiched between a pair of outer layers with a second stiffness that is different than the first stiffness such that a graded stiffness extends across a thickness of the thermal stress compensation layers. The thermal stress compensation layers have a melting point above a sintering temperature and the bonding layers have a melting point below the sintering temperature. The graded stiffness across the thickness of the thermal stress compensation layers compensates for thermal contraction mismatch between the semiconductor device and the metal substrate during cooling from the sintering temperature to ambient temperature.