Analysis of temperature-dependent electrical transport properties of nonvolatile organic field-effect transistor memories based on PMMA film as charge trapping layer

The temperature-dependent electrical transport properties of nonvolatile organic field-effect transistor (OFET) memories with Poly (methyl methacrylate) (PMMA) as a charge trapping layer were characterized at four typical temperatures (20°C, 60°C, 80°C and -78.5°C). It was found that the OFET memories showed strong temperature dependence. The performance degradations, including the memory windows and the retention characteristics, could be observed at both high and low temperatures. The degradations of the OFET memories at 60°C, 80°C and -78.5°C were attributed to both the less electrons trapped by the PMMA film and the easier release of the trapped electrons from the PMMA film, which is caused by the lower crystallinity of pentacene film and the larger contact area between pentacene film and PMMA film, respectively.