Patent ID: 7745865

Claim:
A semiconductor device, comprising: a contact plug formed in a contact opening through a first insulating layer; an etch stop layer on the first insulating layer; a second insulating layer directly on the etch stop layer; a capacitor landing on the contact plug with an overlay shift, comprising a bottom electrode on the top and sidewall of the contact plug, a capacitor dielectric on the bottom electrode, and a top electrode on the capacitor dielectric; wherein the second insulating layer defines the height of the capacitor bottom electrode; wherein one corner of the top surface of the contact plug is covered by the capacitor; wherein the etch stop layer extends to other three corners of the contact plug not covered by the capacitor; and wherein the total thickness Z of the bottom electrode and the capacitor dielectric satisfies at least one of the conditions: Z≧Y or Z≧½X where X is the distance of the overlay shift, and Y is the height of the sidewall of the contact plug covered by the bottom electrode.