Abstract: The invention provides a new transferred electron device, including a substrate, a metal layer forming the cathode contact, an N doped semiconductor input layer and a periodic structure formed of elementary cells; each cell includes a short ballistic doped region defined on each side by a very thin layer, respectively P+ and N+, and followed by a transit region of an homogeneous N doped material. In the short ballistic regions, the electrons acquire the energy necessary for the transfer from the band .GAMMA. to the band L in a time less than the collision time, then the transit regions allow the thermalization of the electrons which arrive at the following ballistic region with a mean energy still equal. A metal contact anode is provided on this last transit region.

Abstract: An electronic control device using a field effect transistor (f.e.t.) of a particular design and capable of causing in a h.f. circuit a phase shift appreciable at a frequency of the order of several Gc/s. To this effect, in a f.e.t. formed by an active layer of a thickness a deposited onto a semiconductor substrate of high resistivity, the gate of the f.e.t. is longer than the thickness a for instance the length of the gate measured along the path of the charge carriers in the conductive channel is of 10 microns, giving an appreciable phase shift at an operating frequency of 10 Gc/s.

Abstract: An apparatus for thermal treatment of the human body, using electromagnetic waves (200 to 2500 Mc/s) and radiometric receivers for monitoring and possibly controlling the temperature reached by the living tissues. A generator at ultra high frequency delivers a power of about one Watt into a coaxial cable terminated by a probe emitting electromagnetic waves in the organ to be heated by dielectric losses in the medium. A multichannel receiver, switched at intervals, analyzes the radiation reemitted by the living tissues through the probe, then utilized as a receiving antenna. The temperature reached in a region surrounding the probe is deduced therefrom and can be utilized for controlling the power emitted through a servocontrol system.

Abstract: A semiconductor structure comprising two conventional electrodes of an avalanche diode and furthermore a supplementary electrode. In a preferred embodiment the conventional and supplementary electrodes form two combs of which the teeth are intermingled and separated from one another by intervals of the same order of magnitude as the thickness of the active layer wherein the avalanche rises. There are two functioning cases. In a first case the biassing voltage applied to the supplementary electrode is lower than the breakdown voltage and the operating conditions of the avalanche diode is optimised or controlled as in a modulator or a frequency shifter. In a second case the biassing voltage applied to the supplementary electrode is higher than the breakdown voltage and the power and/or efficiency of an amplifier or oscillator using such a structure is increased.

Abstract: A circuit capable of providing the negative resistance heart of oscillators or amplifiers in the 5-20 Gc/s frequency band, comprising a central resonant cavity and one or several peripheral exciting chambers, each containing a push-pull arrangement of two diodes for example three pairs of diodes in chambers arranged at 120.degree. from one another on a circle concentric to the central cavity. The diodes are located at the bottoms of cylindrical exciting chambers communicating with the central chamber through holes situated at the center of each push-pull arrangement. Each pair of diodes is maintained and polarized by a metallic bar which plays, with the walls of the exciting chamber, the role of an impedance transformer between the diodes and the central cavity. The metallic bar is maintained by a polarization rod penetrating the chamber through an insulating passage.

Abstract: A circuit for microwave oscillators or amplifiers, yielding the maximum microwave power from negative resistance diodes feeding into one and the same waveguide section. Diodes are arranged in pairs symmetrically at the level of one and the same right section of the waveguide but outside the waveguide cavity. In the case where two diodes are used, these are screwed into clamps arranged in chambers opening into the cavity. Cylinders effect impedance matching between waveguides and diodes and are supported mechanically by a shaft which supplies the direct voltage for the circuit.