Electrical Bistabilities and Conduction Mechanisms of Nonvolatile Memories Based on a Polymethylsilsesquioxane Insulating Layer Containing CdSe/ZnS Quantum Dots

Abstract

Nonvolatile memory (NVM) devices based on a metal–insulator–metal structure consisting of CdSe/ZnS quantum dots embedded in polymethylsilsesquioxane dielectric layers were fabricated. The current–voltage (I–V) curves showed a bistable current behavior and the presence of hysteresis. The current–time (I–t) curves showed that the fabricated NVM memory devices were stable up to 1 × 104 s with a distinct ON/OFF ratio of 104 and were reprogrammable when the endurance test was performed. The extrapolation of the I–t curve to 105 s with corresponding current ON/OFF ratio 1 × 105 indicated a long performance stability of the NVM devices. Schottky emission, Poole–Frenkel emission, trapped-charge limited-current and Child–Langmuir law were proposed as the dominant conduction mechanisms for the fabricated NVM devices based on the obtained I–V characteristics.