Production of an active region over a deep trench capacitor comprises forming a capacitor in a semiconductor substrate, structuring and etching to form the active region, and wet etching the capacitor and the active region

摘要

Production of an active region over a deep trench capacitor comprises forming a capacitor in a semiconductor substrate; structuring and etching the substrate to form the active region so that a part of the active region overlaps with the capacitor; and wet etching the capacitor and the active region. Preferred Features: Wet etching is carried out using ethylene glycol, NH4OH or an etchant having a high selectivity between doped polysilicon and the substrate. Wet etching is carried out for 5-20 minutes. The capacitor is produced by forming a trench in the substrate and forming a stacked capacitor in the trench.