FLOATING-BASE BJT TYPE ESD DEVICE FOR RFID CHIP

Abstract

N-WELL floating base is sandwiched between P+ emitter and P-WELL collector in the proposed floating base vertical PNP electro-static discharge (ESD) protection device. Floating base bipolar junction transistor (BJT) ESD protection device increases the current performance of the parasitic BJT in the ESD mode. During the negative voltage phase of RF antenna signal, the negative voltage range of RF antenna signal is extended to around -10 V at the high RF power field without latch-up failure. The minimum P+ anode layout area of the floating base type BJT ESD device is 400 m2 for the target ESD voltage of 2000 V in human body model (HBM) mode. The parasitic capacitance of the floating base type BJT ESD protection device is about 0.4 pF. The layout area of the proposed floating base type BJT ESD protection device is 50% smaller that of the conventional NMOS diode type ESD protection device for the target ESD voltage of 2000 V in HBM mode. The rewards of the floating base type BJT ESD device will come in the form of improved yields, higher reliability, and substantially lower costs of RFID chip manufacturing.