A method for growing polycrystalline diamond films having engineered grain growth and microstructure. Grain growth of a polycrystalline diamond film on a substrate is manipulated by growing the diamond on a nanopatterned substrate having features on the order of the initial grain size of the diamond film. By growing the diamond on such nanopatterned substrates, the crystal texture of a polycrystalline diamond film can be engineered to favor the preferred <110> orientation texture, which in turn enhances the thermal conductivity of the diamond film.

A method of manufacturing a chip assembly comprises joining an in-process unit to a printed circuit board; reflowing a bonding material disposed between and electrically connecting the in-process unit with the printed circuit board, the bonding material having a first reflow temperature; and then joining a heat distribution device to the plurality of semiconductor chips using a thermal interface material (“TIM”) having a second reflow temperature that is lower than the first reflow temperature. The in-process unit further comprises a substrate having an active surface, a passive surface, and contacts exposed at the active surface; an interposer electrically connected to the substrate; a plurality of semiconductor chips overlying the substrate and electrically connected to the substrate through the interposer, and a stiffener overlying the substrate and having an aperture extending therethrough, the plurality of semiconductor chips being positioned within the aperture.

Methods for obtaining a free-standing thick (>5 μm) epitaxial material layer or heterostructure stack and for transferring the thick epitaxial layer or stack to an arbitrary substrate. A thick epitaxial layer or heterostructure stack is formed on an engineered substrate, with a sacrificial layer disposed between the epitaxial layer and the engineered substrate. When the sacrificial layer is removed, the epitaxial layer becomes a thick freestanding layer that can be transferred to an arbitrary substrate, with the remaining engineered substrate being reusable for subsequent material layer growth. In an exemplary case, the material layer is a GaN layer and can be selectively bonded to an arbitrary substrate to selectively produce a Ga-polar or an N-polar GaN layer.

A package substrate includes a multilayer circuit structure, a gas-permeable structure, a heat conducting component, a first circuit layer, a second circuit layer and a build-up circuit structure. The gas-permeable structure and the heat conducting component are respectively disposed in a first and a second through holes of the multilayer circuit structure. The first and the second circuit layers are respectively disposed on an upper and a lower surfaces of the multilayer circuit structure and expose a first and a second sides of the gas-permeable structure. The build-up circuit structure is disposed on the first circuit layer and includes at least one patterned photo-imageable dielectric layer and at least one patterned circuit layer alternately stacked. The patterned circuit layer is electrically connected to the first circuit layer by at least one opening. The build-up circuit structure and the first circuit layer exposed by a receiving opening form a recess.

Aspects of diamond growth on semiconductors are described. Some aspects include direct growth of synthetic diamond on wide-bandgap semiconductors without the use of nucleating layers or protective layers. Some aspects include generating synthetic diamond over a gallium nitride surface of a layered structure in accordance with a set of growth parameters that are generated based at least in part on an interface property of an interface generated between the gallium nitride surface and the synthetic diamond. In some aspects, the interface is a single interface between the synthetic diamond and the gallium nitride surface. In some aspects, the synthetic diamond is in contact with the gallium nitride surface. Some aspects include synthetic diamond growth on wide-bandgap semiconductor structures to achieve thermal extraction without introducing electrically conductive regions in the semiconductor structure. Such aspects may include generating less than optimal quality synthetic diamond.

Processing forms an integrated circuit structure having first and second layers on opposite sides of an insulator, and an interconnect structure extending through the insulator between the first layer and the second layer. The interconnect structure is formed in an opening extending through the insulator between the first layer and the second layer and has an electrical conductor in the opening extending between the first layer and the second layer and a thermally conductive electrical insulator liner along sidewalls of the opening extending between the first layer and the second layer. The electrical conductor is positioned to conduct electrical signals between the first layer and the second layer, and the thermally conductive electrical insulator liner is positioned to transfer heat between the first layer and the second layer.

Provided is a heat dissipating substrate including a diamond substrate, wherein an upper portion of the diamond substrate has a concave-convex structure including recessed regions that are spaced apart from each other, and insulation patterns that fill the recessed regions. The insulation patterns include at least one of silicon carbide, silicon nitride, silicon oxide, aluminum nitride, and aluminum oxide.

A structure includes: a β silicon nitride crystal phase; and a Y.sub.2MgSi.sub.2O.sub.5N crystal phase. The structure gives a X-ray diffraction pattern by a θ-2θ method, the pattern having a ratio of a peak intensity of a (22-1) plane of the Y.sub.2MgSi.sub.2O.sub.5N crystal phase to a peak intensity of a (200) plane of the β silicon nitride crystal phase, the peak intensity of the (200) plane being determined at a position of 2θ=27.0±1°, the peak intensity of the (22-1) plane being determined at a position of 2θ=30.3±1°, and the ratio being 0.001 or more and 0.01 or less.

An intermediate structure for forming a semiconductor device and method of making is provided. The intermediate device includes (i) a substrate comprising a Ga-based layer, and (ii) optionally, a metal layer on the substrate; wherein at least one of the Ga-based layer and, if present, the metal layer comprises at least a surface region having an isoelectric point of less than 7, usually at most 6.

A semiconductor device includes a source electrode and a drain electrode located over a surface of a semiconductor layer including an electron transit layer and an electron supply layer. A gate electrode is located between the source electrode and the drain electrode. A first diamond layer is located between the source electrode and the drain electrode over the surface with an insulating film therebetween. A second diamond layer is located directly on the surface between the gate electrode and the drain electrode. Of heat generated by the semiconductor layer of the semiconductor device in operation, heat on the side of the electrode on which a relatively strong electric field is applied is efficiently transferred to the second diamond layer. The semiconductor device achieves an excellent heat dissipation property from the semiconductor layer and effectively suppresses overheating and a failure and degradation of the characteristics due to the overheating.