Survey on flash technology with specific attention to the critical process parameters related to manufacturing

In this paper, the history of flash processes will be presented, starting with the 1.2-μm technology to the most current technology. The front- and back-end process modules will be reviewed taking into account the main impact on cell functionality and reliability. In particular, the lithographic and mask issues, the diffusion and cleaning process steps, the chemical mechanical planarization technique to improve planarization, and the high-energy and large-tilted implant will be covered. Finally, the process and equipment trends for the next-generation flash technology will be presented.