| 摘要 |
PURPOSE: A method for forming a charge storage electrode of a capacitor is provided to improve capacitance of the capacitor by realizing uniform-sized grains on both inner and outer walls of the storage electrode. CONSTITUTION: After a semiconductor substrate(10) is provided with an insulating layer(20), a polysilicon layer(30) and a core oxide layer are stacked on the insulating layer(20) and then etched to form a charge storage electrode. Next, a phosphorus-doped amorphous silicon layer(50) is formed thereon and then etched to expose the top of the core oxide layer. The core oxide layer exposed upwardly is then removed, so that a cylinder-shaped storage electrode(A) is formed. Thereafter, inner and outer walls of the storage electrode(A) are simultaneously etched by using etchant to silicon, so that phosphorus at the inner and outer walls keeps the substantially same concentration. After that, silicon atoms are applied to a surface of the storage electrode(A), and a plurality of grains(60) are grown on the surface of the storage electrode(A) under an annealing process.
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