Electrical characteristics and operating mechanisms of nonvolatile memory devices fabricated utilizing core-shell CuInS2-ZnS quantum dots embedded in a poly(methyl methacrylate) layer

Abstract

Nonvolatile memory devices were fabricated with core-shell CuInS2-ZnS quantum dots (QDs) embedded in poly(methyl methacrylate) (PMMA). Capacitance-voltage (C-V) measurements at 300K on the Al/CuInS2-ZnS QDs embedded in PMMA layer/p-Si device showed capacitance hysteresis behaviors with a flatband voltage shift. The memory window of the device increased with increasing applied sweep voltage and saturated at high electric fields due to the current leakage. Capacitance-time measurements showed that the retention time was larger than 1 x 10(5) s that was more than 10 years. The operating mechanisms for the devices are described on the basis of the C-V curves.