Data retention capability is the key to design a highly reliable non-volatile memory cell. We demonstrated in our previous work [1] that the use of p-type floating gate(FG), instead of the commonly used n-type doped FG in an n-channel cell, is feasible for high speed performance as well as better endurance. In this paper, a p-doped floating gate on both n-and p-channel flash cells can be achieved with superior data retention characteristics. Since the p-floating gate cell exhibits a larger tunnel oxide field and a smaller electric field across the ONO dielectric during programming, the p-type FG cell shows much better charge loss behavior as compared to n-type FG ones. Results have been demonstrated for both n-and p-channel flash cells. Along with the high speed, better disturb, and good endurance advantages, the p-type FG cell is very promising for high performance and high reliability applications.

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