Abstract: An ASIC type microcircuit package assembly has a die of at least about 20 millimeters square in size and utilizes as a die attach a polymeric adhesive incorporating a conductive filler. Such microcircuit package assemblies are produced by bonding the die to a substrate with the die attach, curing the die attach, and hermetically sealing the die bonded to the substrate. The microcircuit package assemblies thereby produced are characterized by stability at temperatures of up to about 360.degree. C. and under conditions of stress corresponding to a 12 pound pull following 1,000 temperature cycles between -65.degree. and 150.degree. C., and having a moisture level of less than about 5000 ppm.

Abstract: A light box having one or more fluorescent light source tubes provided with light diffusing and mixing members of tubular form for modifying the light emitted by the fluorescent light tubes to provide a substantially uniformly illuminated backlighted work surface for use in tracing, stripping art work, and viewing color slides, photo negatives, and X-rays. The light box includes internal coated reflective surfaces on bottom and side walls. The light diffusing and mixing member includes light reflective interior and exterior coatings, shaped end portions and in one example perforations providing light transmitting openings. A light diffusing and mixing member of selected light translucent material having shaped end portions and arranged in accordance with the intensity of light emanating from the tubular fluorescent light source.