3 V operation of pentacene-based floating-gate memory realized by the isolation process with Ar/N2-plasma nitridation for N-doped LaB6 metal and high-k LaBxNy insulator stacked structure


 In this paper, we have investigated low-voltage operation of pentacene-based floating-gate (FG) memory utilizing nitrogen-doped (N-doped) LaB6 metal and LaBxNy insulator stacked structure. The pentacene-based FG Au/pentacene/N-doped LaB6(Metal: M)/ LaBxNy (Insulator: I)/ N-doped LaB6(M)/LaBxNy(I)/n+-Si(100) (Semiconductor: S) MIMIS organic field-effect transistor (OFET) was fabricated by utilizing the Ar/N2-plasma nitridation to isolate the edge region of the N-doped LaB6 FG with Au source/ drain (S/D) electrodes. The Ar/N2-plasma nitridation was found to be effective in suppressing the leakage current between the Au S/D electrodes and N-doped LaB6 FG. The pentacene-based FG memory was successfully developed with the memory window (MW) of 0.71 V and the saturation mobility (µsat) of 1.8×10-2 cm2/(V·s), under pulse input of ±3.4 V/10 ms due to the small equivalent oxide thickness (EOT) of 3.1 nm. Furthermore, MW of 0.4 V was obtained under minimum program/erase pulse amplitude/width of ±3 V/100 µs at the process temperature of 200 °C.