The production manner null of DRAM which possesses the case die condenser which has the wrinkle on

摘要

PROBLEM TO BE SOLVED: To provide a stack capacitor of high capacitance value and a stack DRAM in high packing density. SOLUTION: In process, an alternate complex layer structures on both sides of a memory cell contact are etched to form two grooves, and then, irregularities are made on the inner surface of this groove, and the third dielectric layer is etched to partially expose the first polysilicon 18, and the second polysilicon is made, and the above groove is made fully in this second polysilicon, and the etch back is performed to the second polysilicon, and the second polysilicon above the alternate complex layer structure is removed, and the second polysilicon stud 42A is made in the groove. The alternate complex layer structure in the capacitor region, the third dielectric layer, and the first polysilicon 18 are etched to remove the alternate complex layer structure having irregularities on the surface, and the residual third dielectric layer is removed to expose the second polysilicon stud 42A and the first polysilicon 18, thus making the lower electrode of the capacitor.