Integrated lateral structure for esd protection in cmos/bicmos

Abstract

One embodiment of the instant invention is an electrostatic discharge protection device (10) which includes a field-effect transistor, the field-effect transistor comprising: a substrate (12) of a first conductivity type and having a surface and a backside; a gate structure (18) insulatively disposed on the substrate; a blocking region (30) disposed on the substrate and adjacent to the gate structure; a lightly-doped region (32) of a second conductivity type opposite the first conductivity type and disposed within the substrate and beneath the blocking region; a channel region (14) disposed within the substrate, under the gate structure, and adjacent the lightly-doped region; a first doped region (38) of the second conductivity type and disposed within the substrate and adjacent to the lightly doped region, the first doped region spaced away from the channel region by the lightly-doped region; and a second doped region (22) of the second conductivity type and disposed within the substrate, the second doped region spaced away from the first doped region by the channel region. Preferably, a first bipolar transistor (210) is integrated into the electrostatic discharge device and is formed by the substrate, the lightly-doped region and the second doped region and a second bipolar transistor (212) is integrated into the electrostatic discharge device and is formed by the substrate, the first doped region and the second doped region, the first bipolar transistor becoming conductive at a lower voltage during an ESD event than the second bipolar transistor but the second bipolar transistor able to carry more current during the ESD event.