This letter investigates fin-width dependence on single-transistor latch (STL) for bipolar-junction-transistor (BJT)-based 1T-DRAM through experiments. The minimum drain voltage (V(latch)) for the activation of a parasitic lateral BJT in SOI FinFET was measured at various gate lengths (L(G)'s) and fin widths (W(fin)'s). The multiplication factor and current gain of the parasitic BJT in SOI MOSFET are introduced as determinant factors. The experimental results clearly show that the value of V(latch) is reduced in a shorter L(G) and wider W(fin) device. It was found that the nonlocal effect retards the reduction of V(latch) as FinFET scales down.