MOS transistor structure for electro-static discharge protection circuitry

摘要

A MOS transistor structure for an electro-static discharge (ESD) protection circuit of an integrated circuit device. The ESD protection transistor has a structure that comprises a drain diffusion region formed in the silicon substrate of the integrated circuit device, a source diffusion region formed in the silicon substrate, a gate formed in the silicon substrate, and a number of isolated islands evenly distributed throughout the drain diffusion region. The isolated islands provide substantially uniform diffusion resistance between the drain contacts and the gate while increasing the diffusion resistance of the drain region to a level suitable for ESD current protection. The disclosed MOS transistor structure may be fabricated by a salicide technology-based fabrication procedure that is completely compatible with the salicide technology used for the making of the circuitry for the IC device.