Abstract: A lead on chip (LOC) semiconductor leadframe package provides notched lead-fingers to eliminate mechanical shear-stress at the peripheral edge of a semiconductor chip. Opposite rows of substantially flat cantilevered lead-fingers are attached by double-sided adhesive tape in thermal contact with the active face of a chip. The lead-fingers are routed in personalized paths over the face of the chip to cover a large surface area to aid heat dissipation. All wirebond connections between the lead-fingers and the chip are made at a centerline connection strip running down the center of the chip. Each of the cantilevered lead-fingers has a notched portion positioned directly over the vulnerable peripheral chip edge to reduce thermal, mechanical shear-stress. Additionally, since corrosion typically follows a lead path, the notch provides increasing path length to prevent corrosive ingress over the chip face.

Abstract: A lead on chip (LOC) semiconductor leadframe package provides notched lead-fingers to eliminate mechanical shear-stress at the peripheral edge of a semiconductor chip. Opposite rows of substantially flat cantilevered lead-fingers are attached by double-sided adhesive tape in thermal contact with the active face of a chip. The lead-fingers are routed in personalized paths over the face of the chip to cover a large surface area to aid heat dissipation. All wirebond connections between the lead-fingers and the chip are made at a centerline connection strip running down the center of the chip. Each of the cantilevered lead-fingers has a notched portion positioned directly over the vulnerable peripheral chip edge to reduce thermal, mechanical shear-stress. Additionally, since corrosion typically follows a lead path, the notch provides an increasing path length to prevent corrosive ingress over the chip face.

Abstract: A solar heat collection system is provided by utilizing a line-focusing device that is effectively a cylindrically curved concentrator within a protected environment formed by a transparent inflatable casing. A target, such as a fluid or gas carrying conduit is positioned within or near the casing containing the concentrator, at the line focus of the concentrator. The casing can be inflated at the site of use by a low pressure air supply to form a unitary light-weight structure. When deflated, the collector, including casing, concentrator and target, is readily transportable.A system constructed from a plurality of such line-focusing devices can be used either at ground level or on rooftops. A system may advantageously utilize a plurality of parallel aligned heat absorbing rigid conduits as targets, each conduit supporting an inflatable concentrator and casing.

Abstract: A tracking three-dimensional solar energy concentrator is provided by a stretched aluminized polymeric membrane supported by a hoop, the polymeric membrane being formed to a desired curvature by differential loading. The loading on the polymeric membrane determines its curvature. The loading can be varied by utilizing a plastic membrane that has a non-uniform radial distribution of thickness with uniform differential pressure or by applying a non-uniform differential pressure on a membrane having uniform thickness. Reflector membranes having a non-uniform radial distribution of thickness can be obtained by selective spraying of a dissolved plastic such as Krylon on the underside of the aluminized membrane. A non-uniform differential pressure is obtained by using a uniform differential pressure in combination with localized electrostatic or magnetic pressure.