Abstract
The charge trap property of solution-processed zirconium acetylacetonate (ZAA) for solution-processed nonvolatile charge-trap memory (CTM) transistors is demonstrated. Increasing the annealing temperature of the ZAA from room temperature (RT) to 300°C in ambient, the carbon double bonds within the ZAA decreases. The RT-dried ZAA for the p-type organic-based CTM shows the widest threshold voltage shift (∆V(TH) ≈ 80 V), four distinct V(THs) for a multi-bit memory operation and retained memory currents for 10(3) s with high memory on- and off-current ratio (I(M,ON)/I(M,OFF) ≈ 5Ⅹ10(4)). The n-type oxide-based CTM (Ox-CTM) also shows a ∆V(TH) of 14 V and retained memory currents for 10(3) s with I(M,ON)/I(M,OFF) ≈ 10(4). The inability of the Ox-CTM to be electrically erasable is well explained with simulated electrical potential contour maps. It is deduced that, irrespective of the varied solution-processed semiconductor used, the RT-dried organic ZAA as CTL shows the best memory functionality in the fabricated CTMs. This implies that the high carbon double bonds in the low-temperature processed ZAA CTL are very useful for low-cost multi-bit CTMs in flexible electronics.