Robust latchup-immune CMOS structure

摘要

A method is disclosed to provide for more robust latchup-immune CMOS transistors by increasing the breakover voltage VBO, or trigger point, of the parasitic npn and pnp transistors present in CMOS structures. These goals have been achieved by adding a barrier layer to both the n-well and p-well of a twin-well CMOS structure, thus increasing the energy gap for electrons and holes of the parasitic npn and pnp transistor, respectively.