A semiconductor memory device including at least three of the following cell structures: an NVRAM cell structure, an FERAM cell structure, a DRAM cell structure, and an SRAM cell structure. The cell structures are disposed on the same substrate and preferably have gate surfaces which are substantially coplanar. An NVRAM cell structure. Processes for forming a memory structure that includes NVRAM, FERAM, DRAM, and/or SRAM memory structures on one substrate and processes for forming a new NVRAM cell structure.