Dynamic RAM capacitor mfg. method

The production method of capacitor includes the following steps: including multiple material, sandwiching nitride layer between oxide layers, opening storage node contact window in multiple material of alternative oxide layer and nitride layer and stopping to contact pad, along side wall of the contact window removing partial nitride layer, and forming conformal first immediate doped polycrystalline silicon layer on top oxide layer and its contact window, forming a layer of photoresist layer in contact window, removing the first immediate doped polycrystalline silicon layer and removing the photoresist layer, forming conformal thin dielectric layer on top oxide layer and in its contact window, and on the thin dielectric layer forming second immediate doped polycrystalline silicon layer and filling up its contact window.