NOVELTY - The apparatus comprises a heat removing layer for planar mounting to a semiconductor electrical device, where the heat removing layer is a dielectric material, dielectric relief structures that are formed in the dielectric material on a back side facing away from the semiconductor device, protrude into fluid flow and are largely non-planar to a plane of the semiconductor device, a layer mounted on the back of the dielectric material, and voids located within the dielectric material or between the semiconductor electrical device and the dielectric material.    USE - The apparatus such as a structured relief dielectric heat sink is useful for planar photovoltaic cells and semiconductor devices.    ADVANTAGE - The apparatus such as the structured relief dielectric heat sink increases structural strength or strength to weight ratio of the cells, and enables economical heat transfer from the back and/or front of the photovoltaic cells to the surrounding air and surfaces, while mitigating differential thermal stress or optimizes convective heat transfer and radiant heat transfer with respect to cost thus increasing performance and enhancing longevity of the cells.    DETAILED DESCRIPTION - The apparatus comprises a heat removing layer for planar mounting to a semiconductor electrical device, where the heat removing layer is a dielectric material, dielectric relief structures that are formed in the dielectric material on a back side facing away from the semiconductor device, protrude into fluid flow and are largely non-planar to a plane of the semiconductor device, a layer mounted on the back of the dielectric material, and voids located within the dielectric material, between the semiconductor electrical device and the dielectric material or between the dielectric material and the layer formed on the back of the dielectric material. The dielectric material is largely planar to the plane of the semiconductor device on a front side of the dielectric material facing the semiconductor device, and has a similar coefficient of thermal expansion to that of the semiconductor electrical devices. The dielectric relief structures taper away in thickness as the dielectric relief structures protrude into fluid flow. The layer mounted on the back of the dielectric material is: a thermal conductive layer provided on the dielectric relief structures; and a radiant emissive coating applied on the thermal conductive layer on the dielectric relief structures. The thermal conductive layer has: a dissimilar coefficient of thermal expansion to that of the dielectric material; and bends and voids at bases of the relief structures to relieve differential thermal expansion stress. The voids are further located between the thermal conductive layer and the dielectric material layer and located in proximity to the back side of each relief structure to relieve differential thermal expansion stress. The semiconductor electrical device is a photovoltaic cell, a thermoelectric cell, a light emitting diode, an electrical switching diode, a transistor or an integrated circuit. The relief structure is formed by extruding, rolling, stamping, laminating, molding a suspension or powder, painting, printing, bonding and gluing the dielectric material. The dielectric material forms a relief structure with voids by partially extruding into cavities or forming bubbles into the dielectric material into the thermal conductive layer. The thermal conductive layer further comprises metal structures formed by painting, welding, bonding, gluing, electroplating, bending, plasma spraying, laminating or attaching metal structures, or other thermally conductive structures of plates, foils, films, granules, hairs, fins, polymorphic structures or rods. The relief structures in the dielectric material have shapes of bumps, lenses, rods, cones, rectangles, pyramids, ridges, segmented ridges, segmented patterns, hairs, pedestals, networks of ridges, fins, curved fins, asymmetric features, polymorphic structures, crescents, ellipses, barchans and sand-dune like shapes. The relief structures act to create vortex flow in flow passing across surfaces of the relief structures. The radiant emissive coating is formed with a deposit, paint or surface modification, and has a high emissivity in infrared and low absorption in visible light spectrum. The thermal conductive and/or radiant emissive coating has discontinuities or periodic surface folds, and is reflective and/or transparent to visible light. The dielectric material is thicker near a perimeter of the layer to have structural strength, is transparent to visible light, and is a conduit of light to photovoltaic cells.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic view of a relief structured dielectric with expansion gaps.    Fin of first array of fins (60)    Air flow gap between fins (62)    Fins (63)    Gap between heat sink panels (64)    Phase change material or voids in radiant emissive layer. (66)