Reduction of bipolar disturb of floating-body cell (FBC) by silicide and thin silicon film formed at source and drain regions

The cell-to-cell leakage caused by bipolar disturb of the floating-body cell (FBC) has been investigated. In the case of FBC without silicide at the source and drain regions, the change of data "0" to data "1" has been observed in the writing operation to the adjacent cell. However, this leakage can be reduced when the silicide is formed on the thin silicon film at the source and drain regions. It has been clarified that the diffusion of holes inside the n⁺ region is restricted by the capture of holes at the silicide/silicon interface when silicon thickness reduces. Based on these experimental results, 6F² layout of FBC can be realized with the conventional logic device process platform.