Memory effect of an organic based trilayer structure with Au nanocrystals in an insulating polymer matrix

The memory effects of gold (Au) nanocrystal (NC) non-volatile memory structures consisting of polyvinylpyrrolidone (PVP) K-30 polymer tunneling and control layers are investigated. The trilayer structure (PV P/Au-NCs + PV P/PV P) on p-type Si substrate was fabricated by spin coating, and transmission electron microscopy study reveals that the average size of the Au-NCs formed is about 5nm in diameter. Capacitance-voltage (C-V) measurement on the memory structure shows a counter-clockwise hysteresis loop with a significant flat band voltage shift, revealing a memory effect of the Au-NCs with a charge density of up to 1 × 1012cm- 2 and a flat band voltage shift of 2.0V. A unique feature of the double loop in the C-V curves suggests double barriers during electron tunneling. The I-V hysteresis is also characterized, and a switching mechanism of resistive change is discussed.