Abstract: A lift-off process for removing a portion of a metal layer (4). The metal layer is formed on a dielectric polymer substrate with interposition of a corresponding portion of an intermediate layer (2). This process comprises the steps of selecting the material of the intermediate layer so that its interface with the metal has a low adhesivity; applying to the structure a mechanical stress causing detachment of the metal at the interface; and chemically removing the intermediate layer.

Abstract: This invention relates to a process for surface treatment of a substrate carried by an electrode and immersed in a sealed engraving or deposition chamber equipped with plasma generating means, of the type involving the application to the electrodes, of a variable voltage, produced by a generator that is independent of the plasma generating means, wherein said process comprises the steps of:maintaining within said chamber a continuous plasma that is free of electromagnetic fields;supplying said electrode via a low impedance capacitor using a signal comprised of rectangular voltage pulses having:a variable pulse repetition rate to control the energy distribution function of the positive ionic charges bombarding the substrate,a variable mark-to-space ratio for each pulse to control the time distribution of the negative electron charges and the positive ionic charges bombarding the substrate, anda variable pulse amplitude to control the energy of the positive ionic charges bombarding the substrate.

Abstract: Process for the anisotropic etching of a III-V material and application to surface treatment for epitaxial growth.This process includes the step of etching a III-V material (2) by reactive ionic etching using a gaseous mixture containing by volume 20 to 30% of at least one gaseous hydrocarbon, 30 to 50% of at least one inert gas and 20 to 50% of hydrogen.Said etching can be performed locally with the aid of a Si.sub.3 N.sub.4 etching mask (4a).

Abstract: According to the invention, the control messages are constituted by a general addressing message (GCM), followed by shared addressing messages (SACM). The message (GCM) contains all the information common to all the user groups and a confirmation data item of the group of users and the messages (SACM) a shared address. Thus, the group is defined in a manner inherent in the control messages and can undergo reconfiguration at any time.Application to more particularly satellite broadcasting of television programmes.

Abstract: One chip microprocessor, which is more particularly designed to execute culation algorithms of a public code encoding system formed by a public function and a secret inverse function of the type comprising at least one programmable read-only memory, a processing unit and an input/output device, wherein it comprises a memory, in which is recorded at least one algorithm corresponding to the performance of said secret function, and wherein the programmable read-only memory contains the secret parameters constituting the secret code and recorded in an area of the read-only memory which is inaccesible from the outside, the processing unit including the multiplying circuits necessary for the execution of the algorithm.

Abstract: An active matrix display screen which does not include a spurious transistor. The screen includes a matrix of pixels with addressing columns and rows. The addressing rows consist of a stack of semiconductive material, insulating material and conductive material. Where the addressing rows cover conductive segments, a matrix of transistors is formed.

Abstract: The invention relates to a novel oxide for tunable lasers. These oxides comply with the formula:(A.sub.1-x X.sub.x).sub.n (B.sub.1-y Y.sub.y).sub.m O.sub.4in whichA represents one or more elements chosen from the group Mg, Mn and Zn;X represents one or more optically active divalent cations chosen from among V, Ni and Co;B represents one or more elements of the same valence chosen in the group comprising Si, Ge, P, Te, W, Al, In, Ga and Mo;Y represents one or more optically active trivalent cations chosen from among Cr, V and Ni;x is such that 0.ltoreq.x.ltoreq.0.15;y is such that 0.ltoreq.y.ltoreq.0.15; andm and n are integers such that 2n+vm=8 with v representing the valence of B, provided that y=0 when B represents one or more elements chosen from among Si, Ge, P, Te, W and Mo and x and y are not both equal to 0.As an example of such oxides, reference is made to Mg.sub.0.99 Ni.sub.0.01 Al.sub.2 O.sub.