Abstract: A collector-up heterojunction bipolar transistor including, stacked on a substrate, an emitter layer, a base layer, and a collector layer. In this transistor the surface area of the base-emitter junction is of smaller dimensions than the surface area of the base-collector junction. Further, the material of the base layer exhibits a sensitivity of the electrical conductivity to ion implantation that is lower than the sensitivity of the electrical conductivity of the material of the emitter layer to the same ion implantation.

Abstract: A thermal capacitor component which includes, on a substrate, a stack of different layers defined in the form of a mesa terminating at its upper part in an electrical contact layer, which layer is coated with an electrically and thermally conducting layer surmounted by a heat sink element in contact with the conducting layer. The heat sink element has a plane shape. In addition, the component has at least one pad including another stack of layers which is also coated with an electrically and thermally conducting layer. The heat sink element is also in contact with the conducting layer of this stack so as to conduct the heat from the heat sink element into the substrate. Such a thermal capacitor may find application in the cooling of semiconductor components.

Abstract: The invention concerns a bipolar transistor with upper heterojunction comprising in particular stacked on a substrate: an emitter layer (EM); a base layer (BA), a collector layer (CO). In said transistor, the base-emitter junction surface is of smaller dimension than the base-collector junction surface and the material of the base layer has a lower electric conducting sensitivity to ion implantation than the electric conducting sensitivity of the material of the emitter layer to the same ion implant.

Abstract: A semiconductor component of the heterojunction bipolar transistor type comprises, on a substrate, a collector, a base and a mesa-shaped emitter resting on the base. The bipolar transistor furthermore comprises electrically insulating elements in contact with the base and the flanks of the emitter mesa, said elements having a width of the same magnitude as the width of the mesa and providing the component with greater stability. Furthermore, a method for the manufacture of a component of this kind comprises in particular a step for the ion implantation of insulating ions through the constituent layer of the emitter mesa so as to define the electrically insulating elements.

Abstract: A semiconductor component of the heterojunction bipolar transistor type comprises, on a substrate, a collector, a base and a mesa-shaped emitter resting on the base. The bipolar transistor furthermore comprises electrically insulating elements in contact with the base and the flanks of the emitter mesa, said elements having a width of the same magnitude as the width of the mesa and providing the component with greater stability. Furthermore, a method for the manufacture of a component of this kind comprises in particular a step for the ion implantation of insulating ions through the constituent layer of the emitter mesa so as to define the electrically insulating elements.

Abstract: A semiconductor component of the heterojunction bipolar transistor type comprises, on a substrate, a collector, a base and a mesa-shaped emitter resting on the base. The bipolar transistor furthermore comprises electrically insulating elements in contact with the base and the flanks of the emitter mesa, said elements having a width of the same magnitude as the width of the mesa and providing the component with greater stability. Furthermore, a method for the manufacture of a component of this kind comprises in particular a step for the ion implantation of insulating ions through the constituent layer of the emitter mesa so as to define the electrically insulating elements.

Abstract: A semiconductor component that could be a power transistor type of component comprises mesa-structured elementary bipolar transistors. This component has a thick, metal heat sink of which a part (PI) takes the form of a bridge and a part is in contact with the substrate. The legs of the bridge lie on the entire unit constituted by the mesas. The heat sink made on the front face of the substrate may be connected to the rear face of the substrate comprising a ground plate. The discharging of the heat is thus appreciably fostered.

Abstract: Disclosed is a method for the etching of at least two layers of semiconductor materials having different natures, with a view to making a mesa for the self-alignment of the metallizations of a transistor. The heterojunction must comprise a first layer of a material containing As, which is etched by reactive ion etching, and a second layer of a material containing P which is etched chemically. Application to the making of HBT type vertical heterojunction transistors.