A semiconductor device and method for electrostatic discharge protection. The semiconductor device includes a first semiconductor controlled rectifier and a second semiconductor controlled rectifier. The first semiconductor controlled rectifier includes a first semiconductor region and a second semiconductor region, and the second semiconductor controlled rectifier includes the first semiconductor region and the second semiconductor region. The first semiconductor region is associated with a first doping type, and the second semiconductor region is associated with a second doping type different from the first doping type. The second semiconductor region is located directly on an insulating layer.

An ESD device invention comprises first and second transistors formed in a substrate, each having a source, a drain and a gate, the source and drain of the first transaction being connected between ground and an I/O pin or input, the gate of the first transistor being connected to ground and the source and drain of the second transistor being connected between the substrate of the first transistor and the I/O pin or input; first and second capacitors connected in series between ground and the I/O pin or input; and at least a third transistor connected between ground and a node between the first and second capacitors to which the gate of the second transistor is also connected.

An integrated circuit is disclosed comprising at least one I/O pull-down device for protecting I/O logic circuits from electrostatic discharge (ESD). The turn-on voltage of the parasitic bipolar transistor in the I/O pull-down device is lowered by forming under a portion of the lightly doped drain (LDD) region of a first conductivity type of a conventional MOS transistor a second region of a second conductivity type. A P-N junction is formed between the second region and the source/drain regions. The turn-on voltage of the parasitic bipolar transistor in the I/O pull-down device can be reduced by at least 3 volts from that of a comparable device that does not practice the invention and can be varied by varying the concentration of the dopant. A method for forming the circuit including a process for recovering the current of the I/O pull-down device and its advantages are also disclosed.