New Insights on “Capacitorless” Floating-Body DRAM Cells

The notion of a "potential well" for charge storage in the floating body of the "capacitorless" DRAM cell is shown to be inadequate and misleading. The basic operation of the floating-body MOSFET cell (FBC) is physically overviewed, with supportive numerical device simulations and analytical modeling. New insights are revealed, including identification of the intrinsic dynamic capacitors that actually store the body charge. Multiple roles of an accumulation layer that is needed in fully depleted FBCs are physically defined for the first time. Optimal FBC designs are implied