| 摘要 |
PROBLEM TO BE SOLVED: To form fine storage contact holes and a storage node pattern with high accuracy. SOLUTION: On a semiconductor substrate 1 on which an interlayer insulating film 6, a bit contact and bit lines 7-b are formed on transistors, an oxide film 8 and a BPSG film 9 are formed and flattened, and a mask pattern 10 composed of a nitride film is formed on the film 9. Then, another BPSG film 12 is formed on the mask pattern 10 and, after the film 12 is flattened and a resist pattern is formed on the film 12, the film 12 is etched by using the resist pattern as a mask. After the film 12 is etched, the BPSG film 9, oxide film 8, and insulating layer 6 are successively etched. Then, after a polycrystalline silicon film 15 and an oxide film 16 are formed on the entire surface, the films 15 and 16 are subjected to a CMP(chemical mechanical polishing) treatment until the BPSG film 12 is exposed. Thereafter, the films 12 and 16 are removed and dielectric films are formed on storage node electrodes 15. In addition, cell plate electrodes are formed on the dielectric films. |
