An electro-static discharge (ESD) protection device includes a first PN diode, a second PN diode and a silicon controlled rectifier (SCR). The first PN diode and the second PN diode are coupled in series between a pad and a ground voltage to provide a first discharge current path. The SCR is coupled between the pad and the ground voltage to provide a second discharge current path. The SCR has a PNPN structure.

A silicon-controlled rectifier (SCR) includes a first-type field, a second-type first field and a second-type second field disconnectedly formed in a first-type well; an entire first-type doped region formed within the first-type field; a segmented second-type doped region formed within the second-type first field; and a segmented first-type doped region formed within the second-type second field.

An electro-static discharge (ESD) protection device includes a first PN diode, a second PN diode and a silicon controlled rectifier (SCR). The first PN diode and the second PN diode are coupled in series between a pad and a ground voltage to provide a first discharge current path. The SCR is coupled between the pad and the ground voltage to provide a second discharge current path. The SCR has a PNPN structure.

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.

An electrostatic discharge protection device includes: a substrate of a second conductivity type, the substrate including a well of a first conductivity type; a cathode electrode connected to the substrate; a first diffusion region of the second conductivity type and a second diffusion region of the first conductivity type, formed in the substrate and connected to the cathode electrode; an anode electrode connected to the substrate; a third diffusion region of the second conductivity type and a fourth diffusion region of the first conductivity type, formed in the well and connected to the anode electrode; a fifth diffusion region of the first conductivity type, formed on a border of the substrate and the well; and a sixth diffusion region of the first conductivity type, formed in the substrate between the first and second diffusion regions and the fifth diffusion region and configured to receive a bias voltage from outside.

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.

Methods to forming trigger-voltage tunable cascode transistors for an ESD protection circuit in FinFET IC devices and resulting devices. Embodiments include providing a substrate including adjacent first-type well areas, over the substrate, each pair of first-type well areas separated by a second-type well area; providing one or more junction areas in each first and second type well area, each junction area being a first type or a second type; forming fins, spaced from each other, perpendicular to and over the first and second type junction areas; and forming junction-type devices by forming electrical connections between the first and second type junction areas in the first-type well areas and the substrate, wherein a first-stage junction-type device in a first-type well area includes stacked first and second type junction areas, and wherein the first-stage junction-type device is adjacent a second-type well area including first and second type junction areas.

A silicon-controlled rectifier (SCR) includes a first-type field, a second-type first field and a second-type second field disconnectedly formed in a first-type well; an entire first-type doped region formed within the first-type field; a segmented second-type doped region formed within the second-type first field; and a segmented first-type doped region formed within the second-type second field.

A combined semiconductor controlled circuit (CSCC) includes a semiconductor controlled switch (SCS). The SCS includes anode, cathode, anode gate and cathode gate terminals connected to P.sub.1 anode, N.sub.2 cathode, N.sub.1 anode gate and P.sub.2 cathode gate layers. The SCS also includes P-N junctions between P.sub.1 anode and N.sub.1 anode gate layers, N.sub.1 anode gate and P.sub.2 cathode gate layers and P.sub.2 cathode gate and N.sub.2 cathode layers. The CSCC also includes a Zener diode having a current path flowing from the cathode terminal to the anode gate terminal, a feedback resistor connecting cathode and cathode gate terminals and a substrate. A solid-state spark chamber includes a CSCC, a DC bias voltage source and an RC load having a parallel-connected load resistor and capacitor. The solid-state spark chamber also includes a plurality of measurement terminals and a ground. A method of making a solid-state spark chamber includes connecting the above components.

An electrostatic discharge protection circuit is disclosed. A method of manufacturing a semiconductor structure includes forming a semiconductor controlled rectifier including a first plurality of fingers between an n-well body contact and an anode in an n-well, and a second plurality of fingers between a p-well body contact and a cathode in a p-well.