Semiconductor device, e.g. flash memory device, has parasitic transistor formed close to deep trench isolation structure, where doped polysilicon material fills cover section of structure to increase threshold voltage of transistor

摘要

The device has a deep trench isolation structure (216) formed between two troughs within a workpiece, where the structure includes a cover section and a base section. A parasitic transistor is formed in the workpiece close to the structure, and a thin insulating coating coats the structure. A semiconductor material (212) e.g. doped polysilicon material, fills the cover section, to increase the threshold voltage of the transistor. An independent claim is also included for the production of a semiconductor device.