SOI PROTECTION FOR BURIED PLATE IMPLANT AND DT BOTTLE ETCH

摘要

An SOI layer has an initial trench extending therethrough, prior to deep trench etch. An oxidation step, such as thermal oxidation is performed to form a band of oxide on an inner periphery of the SOI layer to protect it during a subsequent RIE step for forming a deep trench. The initial trench may stop on BOX underlying the SOI. The band of oxide may also protect the SOI during buried plate implant or gas phase doping.