A vertical transistor and a manufacturing method thereof are provided herein. The manufacturing method includes forming a first patterned conductive layer on a substrate; forming a patterned metal oxide layer on the first patterned conductive layer, in which the patterned metal oxide layer includes a first patterned insulator layer, a second patterned insulator layer, and a second patterned conductive layer; forming a semiconductor layer; and forming a third patterned conductive layer. The first patterned insulator layer, the second patterned insulator layer, and the second patterned conductive layer are made by using a single metal oxide material. The oxygen concentration of the second patterned conductive layer is different from the oxygen concentrations of the first patterned insulator layer and the second patterned insulator layer.

In a general aspect, a power semiconductor device can include a collector region disposed on a substrate, the collector region can include n-type silicon carbide (SiC). The power semiconductor device can also include a base region disposed on the collector region. The base region can include p-type SiC doped with gallium. The power semiconductor device can include an emitter region disposed on the base region. The emitter region can include n-type SiC carbide.

The disclosure provides bipolar transistor structures with a cavity below an extrinsic base, and methods to form the same. A structure of the disclosure provides a bipolar transistor structure including an extrinsic base protruding from an intrinsic base of a bipolar transistor. The extrinsic base extends over a cavity. An insulator is horizontally adjacent the cavity and below a portion of the extrinsic base. A collector extension region of the bipolar transistor structure extends laterally below the insulator and the cavity.

Bipolar junction transistor (BJT) structures are provided. A BJT structure includes a semiconductor substrate, a collector region formed in the semiconductor substrate, a plurality of base regions formed over the collector region, a plurality of emitter regions formed over the collector region, a ring-shaped shallow trench isolation (STI) region formed in the collector region, a plurality of base conductive layers formed over the collector region and on opposite sides of the base regions, a plurality of sidewall dielectric layers formed on top surfaces of the base conductive layers and disposed vertically between the base conductive layers and upper portions of the emitter regions, and a plurality of base contacts formed on the base conductive layers. The base contacts are divided into a first group of base contacts disposed between the base regions and a second group of base contacts disposed between the base regions and the STI region.

A method of manufacturing a structure in a semiconductor body comprises forming a first mask above a first surface of the semiconductor body. The first mask comprises an opening surrounding a first portion of the first mask, thereby separating the first portion and a second portion of the first mask. The semiconductor body is processed through the opening at the first surface. The opening is increased by removing at least part of the first mask in the first portion while maintaining the first mask in the second portion. The semiconductor body is further processed through the opening at the first surface.

The current disclosure describes techniques for forming gate-all-around (GAA) devices from stacks of separately formed nanowire semiconductor strips. The separately formed nanowire semiconductor strips are tailored for the respective GAA devices. A trench is formed in a first stack of epitaxy layers to define a space for forming a second stack of epitaxy layers. The trench bottom is modified to have determined or known parameters in the shapes or crystalline facet orientations. The known parameters of the trench bottom are used to select suitable processes to fill the trench bottom with a relatively flat base surface.

A bipolar nanocomposite semiconductor (BNS) material in which electrons and holes are separately transported throughout the BNS volume via an interpenetrating plurality of networks, where some of the networks have one conductivity type and others have the opposite conductivity type. The interpenetrating networks can include one or more multiple nanocrystalline structures, metal and dielectric networks and are intimately connected to enable band-like transport of both electrons and holes throughout the material.

A 3D semiconductor device, the device including: a first level including a first single crystal layer and including first transistors each of which includes a single crystal channel; a first metal layer; a second metal layer overlaying the first metal layer; a second level including second transistors and overlaying the second metal layer, each of first memory cells include at least one second transistor; a third level including third transistors and overlaying the second level; a fourth level including fourth transistors and overlaying the third level, each of second memory cells include at least one fourth transistor, where at least one of the second transistors includes a metal gate, where the first level includes memory control circuits which control writing to the second memory cells, and at least one of the second transistors includes a hafnium oxide gate dielectric.

A method for forming a bipolar junction transistor includes forming a collector intrinsic region, an emitter intrinsic region and an intrinsic base region between the collector intrinsic region and the emitter intrinsic region. A collector extrinsic contact region is formed in direct contact with the collector intrinsic region; an emitter extrinsic contact region is formed on the emitter intrinsic region and a base extrinsic contact region is formed in direct contact with the intrinsic base region. Carbon is introduced into at least one of the collector extrinsic contact region, the emitter extrinsic contact region and the base extrinsic contact region to suppress diffusion of dopants into the junction region.

Device structures for a bipolar junction transistor and methods of fabricating a device structure for a bipolar junction transistor. A first semiconductor layer is formed on a substrate, and a second semiconductor layer is formed on the first semiconductor layer. The first semiconductor layer, the second semiconductor layer, and the substrate are etched to define first and second emitter fingers from the second semiconductor layer and trenches in the substrate that are laterally positioned between the first and second emitter fingers. The first semiconductor layer may function as a base layer in the device structure.