The modelling of conventional and novel memory devices has gained significant traction in recent years. This is primarily because the need to store an increasingly larger amount of data demands a better understanding of the working of the novel memory devices, to enable faster development of the future technology generations. Furthermore, in-memory computing is also of great interest from the computational perspectives, to overcome the data transfer bottleneck that is prevalent in the von-Neumann architecture. These important factors necessitate the development of comprehensive TCAD simulation tools that can be used for modeling carrier dynamics in the gate oxides of the flash memory cells. In this work, we introduce the kinetic Monte Carlo module that we have developed and integrated within the Nano Electronic Simulation Software (NESS)-to model electronic charge transport in Flash memory type structures. Using the developed module, we perform retention time analysis for a polyoxometalate (POM) molecule-based charge trap flash memory. Our simulation study highlights that retention characteristics for the POM molecules have a unique feature that depends on the properties of the tunneling oxide. © 2002-2012 IEEE.