A color image was taken with a CMOS image sensor without any infrared cut-off filter, using red, green and blue metal/dielectric filters arranged in Bayer pattern with 1.75 µm pixel pitch. The three colors were obtained by a thickness variation of only two layers in the 7-layer stack, with a technological process including four photolithography levels. The thickness of the filter stack was only half of the traditional color resists, potentially enabling a reduction of optical crosstalk for smaller pixels. Both color errors and signal to noise ratio derived from optimized spectral responses are expected to be similar to color resists associated with infrared filter.

To improve the crack propagation resistance of disk alloys, a study of the influence of the different heat treament parameters, which control the grain boundary geometry, was performed on Astroloy fabricated by a powder metallurgy process. Grain boundary serrations, associated with the precipitation of adjacent coarse y ' precipitates, were obtained by heat treating above the solvus for the alloy followed by slow cooling. The size of these coarse y ' precipitates can be controlled by the heat treatment parameters which include: homogenizing temperature, cooling rate and cooling range.The presence of grain boundary precipitates creates serrations by discontinuous precipitation of the y ' phase in the grain boundary region. The precipitates responsible for serrations were uniformly distributed on both sides of the boundaries. The amplitude of the serrations increase with the misorientation between grains. Tensile tests at 750°C showed no real difference between the microstructures, with and without serrations; however the creep fatigue crack growth rate in the alloy with serrated boundaries was found to be significantly slower than that observed in the unserrated material.

A robust 0.25pm double-poly SiGe HBT structure using non selective epitaxy has been developed. The device features 70/90GHz fT/fmx with pure SiGe base in 0.25pm BiCMOS technology. Performances up to 120/100GHz fT/fmax are demonstrated for SiGe:C base transistors.

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The roles of the subsolvus solutioning temperature and of the ageing temperature on the microstructure and on tensile and creep properties were evaluated on a new PM superalloy, designated NR3. A single-stage ageing treatment was applied instead of the usual double-stage ageing treatment. The principal objective was to improve the creep resistance of this superalloy while keeping a high tensile strength by using a simplified heat treatment.The solution treatment essentially affected the respective proportions of primary and secondary y ' precipitates and the grain size. On the other hand, the major influence of the increase of the ageing temperature was to coarsen the tertiary y ' particles. These microstructural effects were successfully combined to obtained a significant increase of the creep strength associated with a slight rise of the tensile properties.