Abstract: A method in the fabrication of a monolithically integrated vertical device on an SOI substrate comprises the steps of providing an SOI substrate including, from bottom to top, a silicon bulk material, an insulating layer, and an monocrystalline silicon layer; forming an opening in the substrate, which extends into the bulk-material, forming silicon oxide on exposed silicon surfaces in the opening and subsequently removing the formed oxide, whereby steps in the opening are formed; forming a region of epitaxial silicon in the opening; and forming a deep trench in an area around the opening, whereby the steps in the opening are removed.

Abstract: A method in the fabrication of an I2L circuit comprises (i) forming a common base of a lateral bipolar transistor and emitter of a vertical bipolar multicollector transistor, a common collector of the lateral transistor and base of the vertical multicollector transistor, and an emitter of the lateral transistor in a substrate; (ii) forming, from a first deposited polycrystalline layer, a contact region for the common collector/base and a contact region for the emitter of the lateral transistor; (iii) forming an isolation structure for electric isolation of the polycrystalline contact region for the common collector/base; and (iv) forming, from a second deposited polycrystalline layer, a contact region for the common base/emitter and multiple collectors of the vertical multicollector transistor.

Abstract: A method in the fabrication of a monolithically integrated vertical device on an SOI substrate comprises the steps of providing an SOI substrate including, from bottom to top, a silicon bulk material, an insulating layer, and an monocrystalline silicon layer; forming an opening in the substrate, which extends into the bulk-material, forming silicon oxide on exposed silicon surfaces in the opening and subsequently removing the formed oxide, whereby steps in the opening are formed; forming a region of epitaxial silicon in the opening; and forming a deep trench in an area around the opening, whereby the steps in the opening are removed.

Abstract: A method in the fabrication of an I2L circuit comprises (i) forming a common base of a lateral bipolar transistor and emitter of a vertical bipolar multicollector transistor, a common collector of the lateral transistor and base of the vertical multicollector transistor, and an emitter of the lateral transistor in a substrate; (ii) forming, from a first deposited polycrystalline layer, a contact region for the common collector/base and a contact region for the emitter of the lateral transistor; (iii) forming an isolation structure for electric isolation of the polycrystalline contact region for the common collector/base; and (iv) forming, from a second deposited polycrystalline layer, a contact region for the common base/emitter and multiple collectors of the vertical multicollector transistor.

Abstract: A method for producing vertical bipolar transistors having different voltage breakdown and high-frequency performance characteristics on a single die comprises forming, for each of the vertical bipolar transistors, a buried collector region, and base and emitter regions above the buried collector region. The lateral extensions and locations of the base and emitter regions and of the buried collector region are, for each of the vertical bipolar transistors, selected to create an overlap between the base and emitter regions, and the buried collector region, as seen from above, wherein at least some of the overlaps are selected to be different.