A novel p-channel NAND-type flash memory with 2-bit/cell operation and high programming throughput (> 20 MB/sec)

A novel p-channel NAND-type non-volatile flash memory using nitride-trapping device is presented. The p-channel device is programmed by very efficient band-to-band tunneling hot electron (BBHE), and erased by self-converging channel hole tunneling. An ultra-thin bandgap engineered ONO tunneling dielectric as presented in H. T. Lue et al. (2005) is adopted to achieve efficient hole-tunneling erase at high electric field, but yet good data retention at low field. The operation of physically 2-bit/cell NAND-type architecture with depletion mode device (V/sub T/ > 0) is illustrated. Excellent P/E cycling endurance, data retention and read disturb immunity are demonstrated. This new non-volatile p-channel memory device is capable of very high-programming throughput (> 20 MB/sec) suitable for data Flash application.