| 摘要 |
PROBLEM TO BE SOLVED: To increase the surface area of a capacitor electrode and hence drastically increase capacitance more than before, by forming a first projecting part on the capacitor electrode and a second projecting part with a particle diameter smaller than the fist projecting part on the surface of the first projecting part. SOLUTION: In a first step, an HSG grain with a particle diameter of approximately 0.1 μm is formed on the surface of a capacitor electrode. Then, in a second step, an HSG grain 10 with a finer particle diameter of 0.03 μm is formed on the surface of an HSG grain 7. More specifically, be forming a finer HSG grain 10 on the surface of the HSG grain 7, a surface area increase rate can be increased and a capacitance can be increased. For example, an application to a DRAM is considered, the HSG grains 7 and 10 are formed on the surface of the capacitor electrode, a silicon nitride film is deposited on it as a capacitor insulation layer, and then a silicon film containing an impurity is deposited, thus forming a cell plate electrode and hence a capacitor. |
