BULK SEMICONDUCTOR STRUCTURE WITH A MULTI-LEVEL POLYCRYSTALLINE SEMICONDUCTOR REGION AND METHOD

Disclosed is a bulk semiconductor structure that includes a semiconductor substrate with a multi-level polycrystalline semiconductor region that includes one or more first-level portions (i.e., buried portions) and one or more second-level portions (i.e., non-buried portions). Each first-level portion can be within the semiconductor substrate some distance below the top surface (i.e., buried), can be aligned below a monocrystalline semiconductor region and/or a trench isolation region, and can have a first maximum depth. Each second-level portion can be within the semiconductor substrate at the top surface, can be positioned laterally adjacent to a trench isolation region, and can have a second maximum depth that is less than the first maximum depth. Also disclosed herein are method embodiments for forming the bulk semiconductor structure wherein the first-level and second-level portions of the multi-level polycrystalline semiconductor region are concurrently formed (e.g., using a single module).