Miniaturization degree of dynamic MOS RAM cells with readout signal gain

The possible degree of miniaturization is compared for Dynamically Switched Buried Channel (DSC) cells, Taper Isolated Dynamic Gain (TIDG) RAM cells, and DMOS cells. In this comparison, the permitted number of leakage electrons (or holes) N
e
in storage charges is of prime importance. These cells have a readout signal-gain effect, and the signal amount is mostly unaffected by cell miniaturization. However the cells also require charge-storage portions, as well as the conventional single transistor cell. Therefore, cell size depends strongly upon the degree of charge-storage-area miniaturization, which is restricted by N
e
. The N
e
for DSC cells, TIDG cells, and DMOS cells was derived. It was concluded that the N
e
value for the DSC cell is more than twice that for other cells, and this DSC cell size can be reduced the most.