Abstract: The invention relates to an encapsulating box for a semiconductor operating in the range 2 to 20 GHz.At these frequencies, existing boxes have a metal base, an insulating frame and a cover. Two input - output connections pass through the frame. A leak line forms between the input and output by stray capacitive coupling of the connections with the welding metal bands of the cover. The invention opposes this input - output coupling by metallization of the box, with reserves for resists around the connection passages. The metal film joining the welding metal films to the electrical earth of the base reflects the power taken by capacitive coupling on the connections.Insulation obtained: -30 db at 15 GHz. Application to ultra-high frequency components.

Abstract: The invention relates to an ultra-high frequency oscillator operating in the X band. The oscillator circuit comprises a common gate-connected field effect transistor. The source connected tuning circuit comprises a variable capacitor of the varactor type controlled by a voltage and a choke in parallel. The control voltage is decoupled from earth by a capacitor. According to the invention, the transistor, the varactor and the capacitor are integrated into the same box or case in the form of a micromodule. The capacitor acts as a base for the transistor and the varactor, which are welded in juxtaposed manner. The length of the connection between the varactor and the source of the transistor has a minimum value, which makes it possible to broaden the linear frequency band as a function of the control voltage.