An electrostatic protection element including: a first impurity layer of second conductivity type formed on a semiconductor substrate of first conductivity type; a second impurity layer of the first conductivity type formed within the first impurity layer; a first contact layer of the first conductivity type formed in a region within the first impurity layer other than at the second impurity layer; a second and a third contact layer both of the second conductivity type and formed within the second impurity layer; and multilayer wiring connected through a stack structure to the first, the second, and the third contact layer, wherein the stack structure includes at least a first layer wiring connected to each of the first, the second, and the third contact layer, and a second layer wiring connected to the first layer wiring directly above each of the first, the second, and the third contact layer.

An ESD protection semiconductor device includes a substrate, a buried layer buried in the substrate, a first well formed in the substrate, a first doped region formed in the first well, a second doped region formed in the first well and adjacent to the first doped region, a second well formed in the first well, and a third doped region formed in the second well. The buried layer, the first well, the first doped region, and the third doped region include a first conductivity type while the second doped region and the second well include a second conductivity type complementary to the first conductivity type. The second well is spaced apart from the first doped region and the second doped region by the first well.

A first silicon controlled rectifier has a breakdown voltage in a first direction and a breakdown voltage in a second direction. A second silicon controlled rectifier has a breakdown voltage with a higher magnitude than the first silicon controlled rectifier in the first direction, and a breakdown voltage with a lower magnitude than the first silicon controlled rectifier in the second direction. A bidirectional electrostatic discharge (ESD) structure utilizes both the first silicon controlled rectifier and the second silicon controlled rectifier to provide bidirectional protection.

An electrostatic protection includes a buried layer having an outer region and an inner region which are heavily doped regions of a first conductivity type. The inner region is surrounded by an undoped or lightly doped ring region. The ring region is surrounded by the outer region. The device further includes a semiconductor region over the buried layer, a first well of the first conductivity type in the semiconductor region, a first transistor in the semiconductor region, and a second transistor in the semiconductor region. The first well forms a collector of the first transistor and a collector of the second transistor.

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 semiconductor device is provided which comprises an ESD protection device. The structure of the semiconductor device comprises a p-doped isolated region in which a structure is manufactured which operates as a Silicon Controlled Rectifier which is coupled between an I/O pad and a reference voltage or ground voltage. The semiconductor device also comprises a pnp transistor which is coupled parallel to the Silicon Controlled Rectifier. The base of the transistor is coupled to the gate of the Silicon Controlled Rectifier. In an optional embodiment, the base and gate are also coupled to the I/O pad.

A semiconductor device comprising a substrate is disclosed. The substrate comprises: a well of type one; a first doped region of type two, provided in the well of type one; a well of type two, adjacent to the well of type one; a first doped region of type one, doped in the well of type two; and a second doped region of type two, provided in the well of type one and the well of type two, not touching the first doped region of type two. The substrate comprises no isolating material provided in a current path formed by the first doped region of type two, the well of type one, the well of type two and the first doped region of type one.

A high-voltage bipolar semiconductor controlled rectifier (SCR) includes an emitter region having a first polarity and overlying a base region having a second polarity different from the first polarity; a collector region having the first polarity and lying under the base region; an anode region having the second polarity; a first sinker region having the first polarity and contacting the collector region, wherein the anode region is between the first sinker region and the base region; and a second sinker region having the first polarity and contacting the collector region, the second sinker region lying between the anode region and the base region, wherein an extension of the anode region extends under a portion of the second sinker region.

An MTP (Many Times Programmable) memory cell for integrated circuit memory arrays is described. The cell includes an MTP device and a thyristor interconnected so that the MTP device triggers the thyristor to turn on during a Read or Verify operation. The difference in threshold voltages between a data memory cell and a reference memory cell is used to determine the information in the data memory cell. Different memory cell structures may be constructed for different memory array requirements.

A protection device for protecting an IC against electrostatic discharge includes a buried insulant layer having a thickness that is no greater than fifty nanometers with bipolar transistors arranged thereon, one of which is NPN and the other of which is PNP. A base of one merges with a collector of the other. The transistors selectively conduct a discharge current between electrodes. A first semiconductor ground plane under the buried insulant layer is capable of being electrically biased and extends underneath the base of the first bipolar transistor. The ground plane and a base of one transistor have the same doping. However, its dopant density is at least tenfold greater than that of the base.