The influence of a silicon dioxide-filled trench isolation structure and implanted sub-collector on latchup robustness

This paper demonstrates the effect of a new low-cost oxide filled trench isolation structure, and implanted sub-collectors, on the latchup robustness. With scaling and focus on low-cost wireless technology, new technologies are being developed utilizing a shallower oxide-filled trench structure and low-doped implanted sub-collectors. In this paper, the first latchup measurements and corresponding new discoveries are shown, utilizing this new isolation structure and its integration with implanted sub-collectors. This paper compares latchup measurements with the base CMOS technology (e.g. standard dual well p-substrate base technology) to quantify the net improvement. The results are shown with trench isolation only, sub-collector only, and the combined effect of the trench isolation and sub-collector.