A Darlington pair sensor is disclosed. The Darlington pair sensor has an amplifying/horizontal bipolar junction transistor (BJT) and a sensing/vertical BJT and can be used as a biosensor.

The amplifying bipolar junction transistor (BJT) is horizontally disposed on a substrate. The amplifying BJT has a horizontal emitter, a horizontal base, a horizontal collector, and a common extrinsic base/collector. The common extrinsic base/collector is an extrinsic base for the amplifying BJT.

The sensing BJT has a vertical orientation with respect to the amplifying BJT. The sensing BJT has a vertical emitter, a vertical base, an extrinsic vertical base, and the common extrinsic base/collector (in common with the amplifying BJT). The common extrinsic base/collector acts as the sensing BJT collector. The extrinsic vertical base is separated into a left extrinsic vertical base and a right extrinsic vertical base giving the sensing BJT has two separated (dual) bases, a sensing base and a control base.

The Darlington pair sensor has high in-situ signal amplification with low noise and uses substrate space effectively.

Methods of according to the present disclosure can include: providing a substrate including: a first semiconductor region, a second semiconductor region, and a trench isolation (TI) laterally between the first and second semiconductor regions; forming a seed layer on the TI and the second semiconductor region of the substrate, leaving the first semiconductor region of the substrate exposed; forming an epitaxial layer on the substrate and the seed layer, wherein the epitaxial layer includes: a first semiconductor base material positioned above the first semiconductor region of the substrate, and an extrinsic base region positioned above the seed layer; forming an opening within the extrinsic base material and the seed layer to expose an upper surface of the second semiconductor region; and forming a second semiconductor base material in the opening.

A vertical fin field effect transistor including a doped region in a substrate, wherein the doped region has the same crystal orientation as the substrate, a first portion of a vertical fin on the doped region, wherein the first portion of the vertical fin has the same crystal orientation as the substrate and a first portion width, a second portion of the vertical fin on the first portion of the vertical fin, wherein the second portion of the vertical fin has the same crystal orientation as the first portion of the vertical fin, and the second portion of the vertical fin has a second portion width less than the first portion width, a gate structure on the second portion of the vertical fin, and a source/drain region on the top of the second portion of the vertical fin.

The present disclosure relates to a semiconductor device with multiple heterojunction bipolar transistors (HBTs) that have different emitter ballast resistances. The disclosed semiconductor device includes a substrate, a first HBT and a second HBT formed over the substrate. The first HBT includes a first collector, a first base over the first collector, a first emitter over the first base, and a first cap structure over the first emitter. The second HBT includes a second collector, a second base over the second collector, a second emitter over the second base, and a second cap structure over the second emitter. Herein, the first cap structure is different from the second cap structure, such that a first emitter ballast resistance from the first cap structure is at least 1.5 times greater than a second emitter ballast resistance from the second cap structure.

The present disclosure relates to semiconductor structures and, more particularly, to airgap structures in a doped region under one or more transistors and methods of manufacture. The structure includes: a semiconductor material comprising a doped region; one or more sealed airgap structures breaking up the doped region of the semiconductor material; and a field effect transistor over the one or more sealed airgap structures and the semiconductor material.

A semiconductor device of the present invention includes a semiconductor layer including a main IGBT cell and a sense IGBT cell connected in parallel to each other, a first resistance portion having a first resistance value formed using a gate wiring portion of the sense IGBT cell and a second resistance portion having a second resistance value higher than the first resistance value, a gate wiring electrically connected through mutually different channels to the first resistance portion and the second resistance portion, a first diode provided between the gate wiring and the first resistance portion, a second diode provided between the gate wiring and the second resistance portion in a manner oriented reversely to the first diode, an emitter electrode disposed on the semiconductor layer, electrically connected to an emitter of the main IGBT cell, and a sense emitter electrode disposed on the semiconductor layer, electrically connected to an emitter of the sense IGBT cell.

A bipolar transistor includes a collector region having a first doped portion located in a substrate and a second doped portion covering and in contact with an area of the first doped portion. The collector region has a doping profile having a peak in the first portion and a decrease from this peak up to in the second portion.

A method of subdividing a semiconductor wafer is described with trenches in order to provide separate, electrically isolated regions that can be used to hold components that operate at different voltages. There is also described a masking and etching process of forming collector and emitter regions of a lateral bipolar transistor, from a layer of polysilicon deposited on a patterned later of silicon dioxide.

A bipolar transistor includes a collector region having a first doped portion located in a substrate and a second doped portion covering and in contact with an area of the first doped portion. The collector region has a doping profile having a peak in the first portion and a decrease from this peak up to in the second portion.

A semiconductor device includes a semiconductor layer having first and second surfaces, a first electrode and a first gate electrode along the first surface, and a second electrode and a second gate electrode along the second surface. The layer includes a first type first region, a second type second region between the first region and the first surface and facing the first gate electrode, a first type third region between the second region and the first surface and contacting the first electrode, a second type fourth region between the first region and the second surface, facing the second gate electrode, and contacting the second electrode, and a first type fifth region between the fourth region and the second surface and contacting the second electrode. Transistors including the first and second gate electrodes have different threshold voltages that are both positive or negative.