Abstract: An isolation trench formed in a semiconductor substrate has side walls and a bottom wall. Spacers are on the side walls and face each other for forming a narrow channel therebetween. The bottom wall and the spacers are coated with an electrically insulating material for delimiting a closed empty cavity in the channel. The isolation trench is applicable to the manufacture of integrated circuits.

Abstract: Deep isolation trenches having sides and a bottom are formed in a semiconductor substrate. The sides and the bottom are coated with an electrically insulating material that delimits an empty cavity, and forms a plug to close the cavity. The sides of the trench are configured with a neck that determines the depth of the plug, and a first portion that tapers outwards from the neck as the distance from the bottom increases. Deep isolation trenches may be applied, in particular, to bipole and BiCMOS circuits.

Abstract: A method for manufacturing buried connections in an integrated circuit, including the steps of: providing a structure formed of a first support wafer glued at the rear surface of a thin semiconductor wafer, one or several elements of the integrated circuit being possibly formed in and above the thin wafer; gluing a second support wafer on the structure on the front surface side of the thin wafer; removing the first support wafer; forming connections between different areas of the rear surface of the thin wafer; gluing a third support wafer on the connections; and removing the second support wafer.

Abstract: An integrated circuit including a buried layer of determined conductivity type in a plane substantially parallel to the plane of a main circuit surface, in which the median portion of this buried layer is filled with a metal-type material.

Abstract: The vertical bipolar transistor includes an SiGe heterojunction base formed by a stack of layers of silicon and silicon-germanium resting on an initial layer of silicon nitride extending over a side insulation region surrounding the upper part of the intrinsic collector. The stack of layers also extends on the surface of the intrinsic collector which lies inside a window formed in the initial layer of silicon nitride.

Abstract: A vertical bipolar transistor includes a semiconductor substrate, an extrinsic collector layer in the semiconductor substrate, an intrinsic collector on the extrinsic collector, a lateral isolating region surrounding an upper part of the intrinsic collector, an offset extrinsic collector well, a base including a semiconductor region above the intrinsic collector and above the lateral isolating region including at least one silicon layer, and a doped emitter surrounded by the base. The doped emitter may include first and second parts. The first part may be formed from single-crystal silicon and in direct contact with the upper surface of the semiconductor region in a predetermined window in the upper surface above the intrinsic collector. The second part may be formed from polycrystalline silicon. The two parts of the emitter may be separated by a separating oxide layer spaced apart from the emitter-base junction of the transistor.

Abstract: Prior fabricating the transistors, a phase of forming a deep insulative trench in the substrate is followed by a phase of forming a shallow insulative trench in the substrate and extending the deep trench. The phase of forming the deep trench includes coating the inside walls of the deep trench with an initial oxide layer and filling the deep trench with silicon inside an envelope formed from an insulative material. The phase of forming the shallow trench includes coating the inside walls of the shallow trench with an initial oxide layer and filling the shallow trench with an insulative material.

Abstract: A capacitor formed in a substrate including a recess dug into a substrate; a first layer of a dielectric material covering the walls, the bottom and the edges of the recess; a second layer of a conductive material covering the first layer; a third layer of a conductive or insulating material filling the recess; trenches crossing the third layer; a fourth layer of a conductive material covering the walls, the bottoms as well as the intervals between these trenches and the edges thereof; a fifth layer of a dielectric material covering the fourth layer; and a sixth layer of a conductive material covering the fifth layer.

Abstract: A method of manufacturing a bipolar transistor in a single-crystal silicon substrate of a first conductivity type, including a step of carbon implantation at the substrate surface followed by an anneal step, before forming, by epitaxy, the transistor base in the form of a single-crystal semiconductor multilayer including at least a lower layer, a heavily-doped median layer of the second conductivity type, and an upper layer that contacts a heavily-doped emitter of the first conductivity type.

Abstract: Production of an insulated-gate field-effect transistor is begun and interrupted at an uncompleted point. Then, a bipolar transistor is almost completely produced. At that point, a return is made to the production of the insulated-gate field-effect transistor. Lastly, a finishing step common to both transistors and including common thermal annealing and common siliciding is performed.

Abstract: The fabrication process comprises a phase of producing a base region having an extrinsic base and an intrinsic base, and a phase of producing an emitter region comprising an emitter block having a narrower lower part located in an emitter window provided above the intrinsic base. Production of the extrinsic base comprises implantation of dopants, carried out after the emitter window has been defined, on either side of and at a predetermined distance dp from the lateral boundaries of the emitter window so as to be self-aligned with respect to this emitter window, and before the emitter block is formed.

Abstract: An isolation trench formed in a semiconductor substrate has side walls and a bottom wall. Spacers are on the side walls and face each other for forming a narrow channel therebetween. The bottom wall and the spacers are coated with an electrically insulating material for delimiting a closed empty cavity in the channel. The isolation trench is applicable to the manufacture of integrated circuits.

Abstract: The fabrication process comprises a phase of producing a base region having an extrinsic base and an intrinsic base, and a phase of producing an emitter region comprising an emitter block having a narrower lower part located in an emitter window provided above the intrinsic base. Production of the extrinsic base comprises implantation of dopants, carried out after the emitter window has been defined, on either side of and at a predetermined distance dp from the lateral boundaries of the emitter window, so as to be self-aligned with respect to this emitter window, and before the emitter block is formed.

Abstract: A transistor manufacturing process includes the formation, on a layer (15) that will form the base of the transistor, of a stack of an SiGe alloy layer (16), a silicon oxide layer (17) and a silicon nitride layer (18), so as to form in this layer, a false emitter (20), to form, in the layer (15) that will form the base, an extrinsic base region (22) and to siliconize the surface of this extrinsic base region, to cover the extrinsic base region (22) and the false emitter (20) with a silicon dioxide layer (24) which is chemically and mechanically polished down to the level of the false emitter (20), to etch the false emitter (20) in order to form a window (25) and to form, in the window (25) and on the silicon dioxide layer (24), a polysilicon emitter (27). This process has particular application to manufacturing heterojunction bipolar transistors.

Abstract: The process includes successively forming, over a base region of a semiconductor substrate, a poly-Ge or poly-SiGe layer, an etch-stop layer over a selected zone of the Ge or SiGe layer, a layer of poly-Si of the same conductivity type as the base region, then an outer layer of dielectric material. Etching the layers includes stopping at the stop layer to form an emitter window preform, removing the stop film and selectively removing the Ge or SiGe layer in the emitter window preform to form an emitter window and to form an emitter made of poly-Si of conductivity type the opposite of the base region in the window.

Abstract: A process for fabricating a metal-metal capacitor within an integrated circuit comprises the steps of: producing a first metal electrode, a second metal electrode, and a dielectric layer on top of a lower insulating layer; and depositing an upper insulating layer on top of the two metal electrodes and the dielectric layer. The integrated circuit comprises the insulating layer, a first metal layer which is on top of the lower insulating layer, and the upper insulating layer which is on top of the first metal layer. The capacitor comprises the first metal electrode, the second metal electrode, and the dielectric layer wherein each of the two metal electrodes is in contact with one side of the dielectric layer. The electrodes and the dielectric layer lie between the lower insulating layer, which supports a level of metallization (M1), and the upper insulating layer which covers this level of metallization.

Abstract: A method of manufacturing a bipolar transistor in a single-crystal silicon substrate of a first conductivity type, including a step of carbon implantation at the substrate surface followed by an anneal step, before forming, by epitaxy, the transistor base in the form of a single-crystal semiconductor multilayer including at least a lower layer, a heavily-doped median layer of the second conductivity type, and an upper layer that contacts a heavily-doped emitter of the first conductivity type.

Abstract: Prior fabricating the transistors, a phase of forming a deep insulative trench in the substrate is followed by a phase of forming a shallow insulative trench in the substrate and extending the deep trench. The phase of forming the deep trench includes coating the inside walls of the deep trench with an initial oxide layer and filling the deep trench with silicon inside an envelope formed from an insulative material. The phase of forming the shallow trench includes coating the inside walls of the shallow trench with an initial oxide layer and filling the shallow trench with an insulative material.

Abstract: The vertical bipolar transistor includes an SiGe heterojunction base formed by a stack of layers of silicon and silicon-germanium resting on an initial layer of silicon nitride extending over a side insulation region surrounding the upper part of the intrinsic collector. The stack of layers also extends on the surface of the intrinsic collector which lies inside a window formed in the initial layer of silicon nitride.

Abstract: The process includes successively forming, over a base region of a semiconductor substrate, a poly-Ge or poly-SiGe layer, an etch-stop layer over a selected zone of the Ge or SiGe layer, a layer of poly-Si of the same conductivity type as the base region, then an outer layer of dielectric material. Etching the layers includes stopping at the stop layer to form an emitter window preform, removing the stop film and selectively removing the Ge or SiGe layer in the emitter window preform to form an emitter window and to form an emitter made of poly-Si of conductivity type the opposite of the base region in the window.