An ESD device and method using parasitic bipolar transistors that are
silicided. The first embodiment is a parasitic Bipolar Junction
Transistor comprised of n+/n-/p-/n-/n+ regions. The emitter is formed of
the second N+ region and the second N- well. The parasitic base is formed
by the p- substrate or well. The collector is formed of the first well
and the first n+ region. The benefit of the first embodiment is the
trigger voltage is lower because the junction between the n- well
(emitter) and P- substrate (base) and the junction between P- substrate
(base) and the n- well have lower cross over concentrations. The second
embodiment is similar to the first embodiment with the addition of the
first gate. The first gate is preferably connected to the first n+ region
and the Vpad. The third embodiment contains the same elements as the
second embodiment with the addition of a third n+ region. The third n+
region is preferably shorted (or connected) to the first p+ region and
the second n+ region. The third embodiment forms a second NPN parasitic
bipolar using the third N+ region as an emitter. The forth embodiment
contains the same elements as the third embodiment with the addition of a
second gate over the first isolation region. The second gate is
preferably connected to the third n+ region to the first p+ region and
the second n+ region. The gate changes the electrical characteristics of
the first parasitic bipolar transistor.