US 11,658,480 B2
Ultra-low leakage electrostatic discharge device with controllable trigger voltage
Anindya Nath, Essex Junction, VT (US); Zhiqing Li, Halfmoon, NY (US); Souvick Mitra, Essex Junction, VT (US); Alain Loiseau, Williston, VT (US); and Wei Liang, South Burlington, VT (US)
Assigned to GlobalFoundries U.S. Inc., Santa Clara, CA (US)
Filed by GLOBALFOUNDRIES U.S. Inc., Santa Clara, CA (US)
Filed on Oct. 13, 2020, as Appl. No. 17/68,967.
Prior Publication US 2022/0115864 A1, Apr. 14, 2022
Int. Cl. H02H 9/04 (2006.01); H01L 27/02 (2006.01)
CPC H02H 9/046 (2013.01) [H01L 27/0248 (2013.01); H01L 27/0262 (2013.01); H01L 27/0266 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A electrostatic discharge (ESD) device, comprising:
an input pad;
an underlapped field effect transistor (UL-FET) with a trigger voltage Vt, including:
an underlapped drain region coupled to the input pad;
a source region coupled to ground; and
a gate structure coupled to a first terminal of a capacitor and a second terminal of the capacitor coupled to the input pad;
a blocking layer separating the underlapped drain region from the gate structure of the UL-FET by an underlap distance;
a voltage divider for setting a gate voltage Vg applied to the gate structure of the UL-FET; and
a silicon-controlled-rectifier (SCR) device laterally adjacent the UL-FET, the SCR device including a P-N-P-N configuration, the P-N-P-N configuration including a first portion coupled to the input pad and a second portion coupled to ground.