ESD Protection with Asymmetrical Bipolar-Based Device

摘要

An ESD protection device is fabricated in a semiconductor substrate that includes a semiconductor layer having a first conductivity type. A first well implantation procedure implants dopant of a second conductivity type in the semiconductor layer to form inner and outer sinker regions. The inner sinker region is configured to establish a common collector region of first and second bipolar transistor devices. A second well implantation procedure implants dopant of the first conductivity type in the semiconductor layer to form respective base regions of the first and second bipolar transistor devices. Conduction of the first bipolar transistor device is triggered by breakdown between the inner sinker region and the base region of the first bipolar transistor device. Conduction of the second bipolar transistor device is triggered by breakdown between the outer sinker region and the base region of the second bipolar transistor device.

主权项

1. A method of fabricating an electrostatic discharge (ESD) protection device in a semiconductor substrate, the semiconductor substrate comprising a semiconductor layer having a first conductivity type, the method comprising:
performing a first well implantation procedure to implant dopant of a second conductivity type in the semiconductor layer to form inner and outer sinker regions, wherein the inner sinker region is configured to establish a common collector region of first and second bipolar transistor devices of the ESD protection device; performing a second well implantation procedure to implant dopant of the first conductivity type in the semiconductor layer to form respective base regions of the first and second bipolar transistor devices; wherein the first and second well implantation procedures are configured such that conduction of the first bipolar transistor device is triggered by breakdown between the inner sinker region and the base region of the first bipolar transistor device and such that conduction of the second bipolar transistor device is triggered by breakdown between the outer sinker region and the base region of the second bipolar transistor device.