Methods and apparatus for increased holding voltage in silicon controlled rectifiers for ESD protection

摘要

Methods and apparatus for increased holding voltage SCRs. A semiconductor device includes a semiconductor substrate of a first conductivity type; a first well of the first conductivity type; a second well of a second conductivity type adjacent to the first well, an intersection of the first well and the second well forming a p-n junction; a first diffused region of the first conductivity type formed at the first well and coupled to a ground terminal; a first diffused region of the second conductivity type formed at the first well; a second diffused region of the first conductivity type formed at the second well and coupled to a pad terminal; a second diffused region of the second conductivity type formed in the second well; and a Schottky junction formed adjacent to the first diffused region of the second conductivity type coupled to a ground terminal. Methods for forming devices are disclosed.

主权项

1. A semiconductor device comprising:
a p-n junction formed between a first well and a second well; each of the first well and the second well including, formed at a top surface thereof, a first diffused region of the same conductivity type as the well and a second diffused region of the opposite conductivity type as the well; the first well including, formed at the top surface, a Schottky junction laterally displaced from and electrically coupled to the first diffused region and the second diffused region of the first well; and a polysilicon gate extending over the p-n junction.