Capacitor for semiconductor device and manufacturing method of capacitor for semiconductor device

摘要

Disclosed are a capacitor for a semiconductor device and a manufacturing method thereof. The capacitor includes a second oxide layer filling a first trench in a semiconductor substrate; second and third trenches in an active region at opposing sides of the second oxide layer in the first trench; a third oxide layer on the semiconductor substrate and on inner surfaces of the second and third trenches; and a polysilicon layer on the third oxide layer to fill the second and third trenches.