New programming and erasing schemes for p-channel flash memory

In this work, a new programming scheme using a forward substrate bias during BBHE injection and a two-step erasing scheme has been suggested to improve the performances of p-channel flash memory. It has been found that applying a forward substrate bias increases the electron injection efficiency and improves the cell's endurance characteristics. The two-step erasing scheme, where a channel erase cycle is added after the source erase operation, is found to reduce the gate current degradation and also to improve the cell's endurance characteristics.