An ESD protection semiconductor device includes a substrate, a gate set formed on the substrate, a source region and a drain region formed in the substrate respectively at two sides of the gate set, at least a first doped region formed in the source region, and at least a second doped region formed in the drain region. The source region, the drain region and the second doped region include a first conductivity type, and the first doped region includes a second conductivity type. The first conductivity type and the second conductivity type are complementary to each other. The second doped region is electrically connected to the first doped region. The gate set includes at least a first gate structure, a second gate structure, and a third gate structure.

An ESD protection device and a method of forming the same, the ESD device includes a substrate, a first doped well, a second doped well, a source and drain regions and a guard ring. The first doped well with a first conductive type is disposed in the substrate. The source and drain regions with the second conductive type are disposed in the first doped well. The guard ring with the first conductive type is also disposed in the first doped well and has a first portion extending along a first direction and a second portion extending along a second direction different from the first direction. The second doped well with the second conductive type is also disposed in the first doped well between the drain region and the second portion of the guard ring to in contact with the drain region in the first direction.

A semiconductor device includes a plurality of gate electrodes, and a plurality of stripe contacts, each formed alternately with each of the gate electrodes along a length direction of the gate electrodes. A conductive transistor with a reference potential applied to one of the stripe contacts forming one of a source and a drain is formed. One of the gate electrodes adjacent to one of the stripe contacts forming the other of the source and the drain is used as a first dummy gate electrode. The semiconductor device further includes a metal extending over the first dummy gate electrode to electrically connect together the stripe contacts formed on opposing sides of the first dummy gate electrode, and a pad connected to one of the stripe contacts formed on opposing sides of the first dummy gate electrode, which is provided across the first dummy gate electrode from the conductive transistor.

In a circuit portion, a p.sup.+-type diffusion region penetrates, in the depth direction, an n.sup.-type base region on the front side of a base substrate and surrounds a MOSFET. In a protective element portion on the same substrate, a p.sup.++-type contact region, an n.sup.+-type diffusion region, and a p.sup.+-type diffusion region are selectively provided in a p.sup.+-type diffusion region on the front side of the base substrate. The p.sup.+-type diffusion region penetrates the p.sup.-type diffusion region in the depth direction, on the outer periphery of the p.sup.-type diffusion region. An n.sup.+-type source region, the p.sup.+-type diffusion region, the p.sup.++-type contact region, and the n.sup.+-type diffusion region are connected to a GND terminal. The rear surface of the substrate is connected to a VCC terminal. A snapback start voltage of a parasitic bipolar element of the protective element portion is lower than that of the circuit portion.

An electrostatic discharge (ESD) protection circuit includes a field oxide device in a substrate, wherein the field oxide device is coupled between an input/output (I/O) pad and a first terminal. The field oxide device includes a drain end and a source end having a first type of dopant. The field oxide device includes a field oxide structure between the drain end and the source end. The field oxide structure has a top surface co-planar with a top surface of a substrate. A first doped region having a second type of dopant is adjacent to the drain end. A second doped region having the second type of dopant is adjacent to the source end. The field oxide structure is in a well and the source end and the drain end are separate from the well. The substrate has the second type of dopant and is around the field oxide structure.

A semiconductor device includes a plurality of gate electrodes, and a plurality of stripe contacts, each formed alternately with each of the gate electrodes along a length direction of the gate electrodes. A conductive transistor with a reference potential applied to one of the stripe contacts forming one of a source and a drain is formed. One of the gate electrodes adjacent to one of the stripe contacts forming the other of the source and the drain is used as a first dummy gate electrode. The semiconductor device further includes a metal extending over the first dummy gate electrode to electrically connect together the stripe contacts formed on opposing sides of the first dummy gate electrode, and a pad connected to one of the stripe contacts formed on opposing sides of the first dummy gate electrode, which is provided across the first dummy gate electrode from the conductive transistor.

An ESD protection semiconductor device includes a substrate, a gate set formed on the substrate, a source region and a drain region formed in the substrate respectively at two sides of the gate set, at least a first doped region formed in the source region, and at least a second doped region formed in the drain region. The source region, the drain region and the second doped region include a first conductivity type, and the first doped region includes a second conductivity type. The first conductivity type and the second conductivity type are complementary to each other. The second doped region is electrically connected to the first doped region.

An electrostatic discharge protection device and a method of making the same. The device includes a device area located on a semiconductor substrate. The device also includes an array of coextensive, laterally spaced fingers located within the device area. Each finger includes an elongate source and an elongate drain separated by an elongate gate. The fingers are electrically connected in parallel for conducting an electrostatic discharge current during an electrostatic discharge event. The device further includes a plurality of body contact regions. A layout of the body contact regions is graded such that a greater number of the body contact regions, larger body contact regions, or both are located towards a periphery of the device area than towards a central part of the device area. The layout of the body contact regions may encourage triggering of the electrostatic discharge protection device within the central part of the device area.

A method of fabricating an electrostatic discharge protection structure includes the following steps. Firstly, a semiconductor substrate is provided. Plural isolation structures, a well region, a first conductive region and a second conductive region are formed in the semiconductor substrate. The well region contains first type conducting carriers. The first conductive region and the second conductive region contain second type conducting carriers. Then, a mask layer is formed on the surface of the semiconductor substrate, wherein a part of the first conductive region is exposed. Then, a first implantation process is performed to implant the second type conducting carriers into the well region by using the mask layer as an implantation mask, so that a portion of the first type conducting carriers of the well region is electrically neutralized and a first doped region is formed under the exposed part of the first conductive region.

A device includes a transistor configured for operating in a hybrid mode, an element configured for generating and injecting a current into the substrate of the transistor in the presence of an ESD pulse, and a thyristor triggerable at least by the element.