The present disclosure relates to semiconductor structures and, more particularly, to vertically stacked diode-trigger silicon controlled rectifiers and methods of manufacture. The structure includes: a silicon controlled rectifier in a trap rich region of a semiconductor substrate; and at least one diode built in polysilicon (gate material) and isolated by a gate-dielectric.

A 3D semiconductor device including: a first level including a first single crystal layer and first transistors, which each include a single crystal channel; a first metal layer with an overlaying second metal layer; a second level including second transistors, overlaying the first level; a third level including third transistors, overlaying the second level; a fourth level including fourth transistors, overlaying the third level, where the second level includes first memory cells, where each of the first memory cells includes at least one of the second transistors, where the fourth level includes second memory cells, where each of the second memory cells includes at least one of the fourth transistors, where the first level includes memory control circuits, where second memory cells include at least four memory arrays, each of the four memory arrays are independently controlled, and at least one of the second transistors includes a metal gate.

A field-effect transistor includes a substrate, a channel on the substrate including a stem including silicon extending in a vertical direction from the substrate and a number of prongs including silicon extending in a horizontal direction from the stem and spaced apart from each other along the vertical direction, an interfacial layer surrounding the stem and the prongs of the channel, a dielectric layer on the interfacial layer and surrounding the stem and the prongs of the channel, and a metal gate on the dielectric layer and surrounding the stem and the prongs of the channel.

A transient voltage suppressing (TVS) device formed in an epitaxial layer of a first conductivity type supported on a semiconductor substrate. The TVS device further comprises a plurality of contact trenches opened and extended to a lower part of the epitaxial layer filled with a doped polysilicon layer of a second conductivity type wherein the trenches are further surrounded by a heavy dopant region of the second conductivity type. The TVS device further includes a metal contact layer disposed on a top surface of the epitaxial layer electrically connected to a Vcc electrode wherein the metal contact layer further directly contacting the doped polysilicon layer and the heavy dopant region of the second conductivity type.

A transient-voltage suppressing (TVS) device disposed on a semiconductor substrate including a low-side steering diode, a high-side steering diode integrated with a main Zener diode for suppressing a transient voltage. The low-side steering diode and the high-side steering diode integrated with the Zener diode are disposed in the semiconductor substrate and each constituting a vertical PN junction as vertical diodes in the semiconductor substrate whereby reducing a lateral area occupied by the TVS device. In an exemplary embodiment, the high-side steering diode and the Zener diode are vertically overlapped with each other for further reducing lateral areas occupied by the TVS device.

The present application teaches, inter alia, methods and circuits for operating a B-TRAN (double-base bidirectional bipolar junction transistor). Exemplary base drive circuits provide high-impedance drive to the base contact region on the side of the device instantaneously operating as the collector. (The B TRAN is controlled by applied voltage rather than applied current.) Current signals operate preferred implementations of drive circuits to provide diode-mode turn-on and pre-turnoff operation, as well as a hard ON state with low voltage drop (the transistor-ON state). In some preferred embodiments, self-synchronizing rectifier circuits provide adjustable low voltage for gate drive circuits. In some preferred embodiments, the base drive voltage used to drive the c-base region (on the collector side) is varied while base current at that terminal is monitored, so no more base current than necessary is applied. This solves the difficult challenge of optimizing base drive in a B-TRAN.

A transient-voltage suppressing (TVS) device disposed on a semiconductor substrate including a low-side steering diode, a high-side steering diode integrated with a main Zener diode for suppressing a transient voltage. The low-side steering diode and the high-side steering diode integrated with the Zener diode are disposed in the semiconductor substrate and each constituting a vertical PN junction as vertical diodes in the semiconductor substrate whereby reducing a lateral area occupied by the TVS device. In an exemplary embodiment, the high-side steering diode and the Zener diode are vertically overlapped with each other for further reducing lateral areas occupied by the TVS device.

Provided is an electrostatic protection circuit that has little leakage current under normal operation and allows a trigger voltage to be set comparatively freely, without requiring a special process step. This electrostatic protection circuit is provided with a series circuit including a transistor, a predetermined number of diodes and an impedance element that are connected in series between the first node and the second node, and a discharge circuit configured to send current from the first node to the second node following an increase in a potential difference that occurs between both ends of the impedance element, when the first node reaches a higher potential than the second node and current flows through the series circuit. The predetermined number of diodes are connected between the source and the back gate of the transistor.

A bidirectional power switch includes first and second thyristors connected in antiparallel between first and second conduction terminals of the switch. The first thyristor is of an anode-gate thyristor, and the second thyristor is of a cathode-gate thyristor. The gates of the first and second thyristors are coupled to a same control terminal of the switch by respective dipole circuits. At least one of the dipole circuits is formed by at least one diode or at least one resistor.

The present application teaches, inter alia, methods and circuits for operating B-TRANs (double-base bidirectional bipolar junction transistors). Base drive circuits provide high-impedance drive to the base contact region on whichever side of the device is (instantaneously) operating as the collector. (B-TRANs, unlike other bipolar junction transistors, are controlled by applied voltage, not applied current.) Control signals operate preferred drive circuits, providing diode-mode turn-on and pre-turnoff operation, and a hard ON state with a low voltage drop (the transistor-ON state). In some (not necessarily all) preferred embodiments, a self-synchronizing rectifier circuit provides an adjustable low voltage for the gate drive circuit. Also, in some preferred embodiments, the base drive voltage used to drive the c-base region (on the collector side) is varied while monitoring the base current at that terminal, so that no more base current than necessary is applied. This solves the difficult challenge of optimizing base drive in B-TRANs.