Trench isolation at 300 nm active pitch using x-ray lithography

A nanofabrication technology providing device isolation at an active pitch of 300 nm has been developed using x-ray lithography for pattern definition. The isolation scheme uses oxide filled trenches etched into the silicon substrate, which are 300-350 nm deep and have a 150 nm minimum width. Chemical mechanical polishing is utilized to achieve global planarization. The superior diode leakage and gate oxide (t(OX)=55 Angstrom) performance, excellent metal-oxide-semiconductor field effect transistor characteristics, and robust latch-up behavior demonstrated by this trench isolation technology, present it as a key enabler for continued scaling of semiconductor technologies. The experimental data presented predicts that with careful attention to process integration, trench isolation can be scaled well into the sub-0.25 mu m size scale. (C) 1996 American Vacuum Society.