The present invention discloses a method of manufacturing a capacitor, which includes the steps of forming a capacitor recess in a sacrificial layer, wherein the sidewall of capacitor recess has a wave profile, forming a bottom electrode layer on the sidewall of capacitor recess, filling up the capacitor recess with a supporting layer, removing the sacrificial layer to forma capacitor pillar made up by the bottom electrode layer and the supporting layer, forming a capacitor dielectric layer on the capacitor pillar, and forming a top electrode layer on the capacitor dielectric layer.