Metal Nanocrystal Memory Device Simulation And Modeling

As the feature size of integrated circuits process is scaling down to 50nm, traditional floating gate based structure won't be competent for non-volatile application resulting from slow P/E speed and poor data retention performance. Metal nanocrystal is considered as a potential subsititute of floating gate based structure. Thus, it's necessary to identify the factors that influence the program/erase (P/E) speed and the retention performance of metal nanocrystal memory.Works in this paper gives an extensive study about metal nanocrystal memory concerning floating-gate structure capactitor model calculation, TCAD simulation and data retention capability modeling. Research results indicate that:(a)Increasing workfunction of floating gate doesn't affect the programming speed of the device while slow the earse speed and improve the data retention capability. (b)Increasing workfunction of control gate decreases the devices's programming speed, increases the erasing speed and doesn't affect retention. (c) Increasing the density and diameter of the metal nanocrystal increases programming speed. (d)Coulomb Blockade can severely deteriorate the data retention capability of the device. (e)It's estimated that metal nanocrystal memory device can conservatively have 30 year data retention capability with Pt nanocrystal and 4nm thickness tunneling oxide.