Abstract: An electrically written memory element utilizing the motion of protons within a dielectric layer surrounded by layers on either side to confine the protons within the dielectric layer with electrode means attached to the surrounding layers to change the spatial position of the protons within the dielectric layer. The device is preferably constructed as a silicon-silicon dioxide-silicon layered structure with the protons being introduced to the structure laterally through the exposed edges of the silicon dioxide layer during a high temperature anneal in an atmosphere containing hydrogen gas. The device operates at low power, is preferably nonvolatile, is radiation tolerant, and is compatible with convention silicon MOS processing for integration with other microelectronic elements on the same silicon substrate. With the addition of an optically active layer, the memory element becomes an electrically written, optically read optical memory element.

Abstract: A method for determining the complete elimination of a thin layer (3) deposited on a substrate (1) includes the steps of providing on an area of the substrate (1) an optical diffraction grating (2, 2'), the thin layer deposited on the substrate also covering this diffraction grating, and the etching of the thin layer being also carried out in the area of the diffraction grating; illuminating the grating (2, 2') with a monochromatic light beam; and observing the evolution of the diffracted light during the etching of the thin layer, in order to determine the moment when the material of the thin layer is entirely removed.

Abstract: A method for measuring the viscosity of a material consists in forming an array of parallel strips of material for constituting a diffraction grating; illuminating the array with a monochromatic light beam which produces a diffraction grating comprised of a main light spot (5) and of a plurality of adjacent diffraction spots, the envelope of which exhibits a major lobe (LO) including the main spot (5) and minor lobes (L1, L2); subjecting the array to a thermal process consisting in rapidly heating it at a predetermined temperature (T) and maintaining it at such temperature; selecting the brightest spot (6) among those of the first lobe (L1) and measuring the evolution of its light intensity (HL1) during the thermal process; determining the time interval elapsing until the first passage by a minimum intensity value (HL1b) of the spot (6); and deducting therefrom the value (.nu.) of the viscosity of the material constituting the array by the formula 1/.nu.=.alpha.d.

Abstract: An amplification device relating to the field of the amplification of ultra-wideband electrical signals from the dc to the microwave range, and more precisely from dc to microwaves of over 6 GHz, notably for the amplification of signals transmitted at very high bit rates on optic fibers, of the type including at least one ampification stage, the active amplification element of which is a field-effect transistor mounted as a common source, each of the amplification stages including means for the simultaneous maintaining of a positive dc voltage bias on the drain of the amplification transistor and a negative or zero dc bias on the gate of the transistor. This device may advantageously be made in monolithic integrated circuit form.