Freescale Semiconductor,inc.

Le Centre National De La Recherche Scientifique (cnrs)

Nicolas Nolhier

Patrice Besse

Michel Zecri

Philippe Renaud

Amaury Gendron

Luca Bertolini

Maryse Bafleur

An ESD protection device, which is arranged to be active at a triggering voltage (Vt) for providing ESD protection, comprises a first region of the first conductivity type formed in a semiconductor layer of the first conductivity type, the first region extending from a surface of the semiconductor layer and being coupled to a first current electrode (C) of the semiconductor device, a well region of a second conductivity type formed in the semiconductor layer extending from the surface of the semiconductor layer, and a second region of the second conductivity type formed in the well region, the second region being coupled to a second current electrode (B). The ESD protection device further comprises a floating region of the second conductivity type formed in the semiconductor layer between the first current electrode (C) and the well region and extending from the surface of the semiconductor layer a predetermined depth. The floating region is separated from the well region by a predetermined distance, a value of which is selected such that the floating region is located within a depletion region of a PN junction between the well region and the semiconductor layer when the ESD protection device is active. The floating region has a doping concentration selected such that the floating region is not fully depleted when the ESD protection device is active and the predetermined depth is selected such that the floating region modifies a space charge region near the PN junction. An ESD protection device according to a second embodiment is also disclosed.

ESD protection device and method of forming an ESD protection device

A semiconductor switch arrangement comprises a bipolar transistor and a semiconductor power switch having an input node, an output node and a control node for allowing a current path to be formed between the input node and the output node. The bipolar transistor is coupled between the input node and the control node such that upon receiving an electro-static discharge pulse the bipolar transistor allows a current to flow from the input node to the control node upon a predetermined voltage being exceeded at the input node to allow the control node to cause a current to flow from the input node to the output node. Thus, the bipolar transistor device protects the semiconductor switch device, such as an LDMOS device, against ESD, namely protection against power surges of, say, several amperes in less than 1 usec.

Semiconductor switch arrangement and an electronic device

An arrangement () and method for scalable ESD protection of a semiconductor structure (), a protection structure () providing a discharge transistor () path from an input/output node () to ground or another node if a threshold voltage is reached, wherein the discharge transistor is a self-triggered transistor having collector/drain () and emitter/source () regions, and a base/bulk region () having one or more floating regions () between the collector/drain () and emitter/source () regions. The floating region (N or P) modulates the threshold voltage Vtl for ESD protection. Vtl can be adjusted by shifting the floating region location. Splitting of the electric field into two parts reduces the maximum of the electric field. Vtcan be adjusted volt-by-volt to suit application needs. ESD capability is increased by better current distribution in the silicon. This provides the advantages of reduced die size, faster time-to-market, less redesign cost, and better ESD performance.

Arrangement and method for ESD protection

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Espanes, France

Nicolas Nolhier