Method for forming a cylinder capacitor in the dram process
 A method for fabricating a cylindrical capacitor is described. Semiconductor device structures, including a capacitor node contact region, are formed on a semiconductor substrate. A first insulating layer is deposited over the device structures and planarized. A silicon nitride layer and then a second insulating layer are deposited over the first insulating layer. A contact opening having a first width is etched through the insulating layers and the silicon nitride layer to the capacitor node contact region. A photoresist mask is formed over the second insulating layer having a mask opening over the contact opening wherein the mask opening has a second width wider than the first width and wherein photoresist residue remains at the bottom of the contact opening. A second opening is etched in the second insulating layer corresponding to the mask opening wherein the photoresist residue protects the semiconductor substrate within the contact opening during etching. The photoresist mask and residue are removed. A first layer of polysilicon is deposited to fill the contact opening. The first polysilicon layer overlying the second insulating layer is polished away to form the bottom electrode of the capacitor. The second insulating layer is removed. A capacitor dielectric layer is deposited over the silicon nitride layer and the first polysilicon layer. A second polysilicon layer is deposited overlying the capacitor dielectric layer to form the top electrode of the capacitor. 
Taiwan Semiconductor Manufacturing Company, Ltd.
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H01L H01L
inventional inventional
Yu-Hua Jenn Ming
Lee Huang