Patent ID: 7666738
Filing Date: 2010-02-23
Classification: H01L

Abstract:
1. A method for fabricating a capacitor of a semiconductor device, the method comprising: forming an insulation layer having contact holes on an upper surface of a substrate; forming a plurality of plugs connected to the substrate by being filled into the contact holes; forming an isolation layer having holes exposing the plurality of the plugs on the insulation layer; forming a first amorphous silicon layer doped with a first doping concentration over the isolation layer and the plurality of plugs, wherein the first doping concentration suppresses dopants from locally agglomerating; forming a second amorphous silicon layer on the first amorphous silicon layer in an in-situ condition, wherein the second amorphous silicon layer is substantially undoped; patterning the first amorphous silicon layer and the second amorphous silicon layer to form a storage node; converting the second amorphous silicon layer to form a plurality of silicon grains on an inner wall of the fist amorphous silicon layer, wherein substantially all of the second amorphous silicon layer is converted to the silicon grains; doping the storage node and the silicon grains with dopants until a second doping concentration is reached, wherein the second doping concentration provides conductivity to the storage node; removing the isolation layer; additionally doping the storage node and the silicon grains with dopants to compensate a doping profile of the storage node; and forming sequentially a dielectric layer and a plate over the storage node.