A Highly Reliable Logic NVM "eCFlash (Embedded CMOS Flash)" Utilizing Differential Sense-Latch Cell with Charge-Trapping Storage

A new logic NVM "eCFlash (embedded CMOS Flash)" has been developed without any additional process steps in a 0.25 um technology. In this architecture, a novel differential sense-latch cell with charge-trapping storage is adopted. This unique cell structure functions as a differential sense amplifier as well as a data latch, therefore mass data can be restored to each cell's latch simultaneously for static data output with high sensitivity and low power consumption. Furthermore the handling scheme of twice the breakdown voltage with novel charge pump circuit and high voltage driver is demonstrated. By utilizing these techniques, a highly reliable Logic NVM is realized; 100 K cycling endurance and data retention of 20 years at 150C.