Memory method for nanocrystalline floating gate structure-based multi-value nonvolatile memory

Abstract

The invention relates to a memory method for a nanocrystalline floating gate structure-based multi-value nonvolatile memory, and belongs to the technical field of memories. In the memory method, hot electron injection is used as a programming mode, Fowler-Nordheim (FN) tunneling is used as an erasing mode, and four memory states of 00, 01, 10 and 11 are differentiated according to amplitude of read current, so that multi-value memory can be realized under the condition of the same area to double memory capacity. In the method, the new programming mode is adopted to simultaneously program at asource end and a drain end, and the multi-value memory is formed, so that the programming efficiency is greatly improved, a memory window is also increased, memory of more points is realized, and thememory capacity which is twice the conventional memory capacity is realized on a memory unit of the same size; in addition, a manufacturing process is not changed while the advantage is realized, andthe cost is greatly reduced.

Description

technical field [0001] The invention relates to the technical field of memory, in particular to a storage method of a multi-valued non-volatile memory based on a nanocrystal floating gate structure. Background technique [0002] In recent years, the growth rate of memory in integrated circuits has exceeded that of logic circuits. The proportion of memory in chip area has increased from 20% in 1999 to 71% in 2005, while logic circuits have decreased from 66% in 1999 to 2005. 16%. Among memory products, the fastest growing market demand is non-volatile memory. As a typical device of non-volatile memory, flash memory (Flash Memory) has been widely used in various handheld mobile storage electronic products such as U disk, MP3 player and mobile phone. However, the flash memory device structure widely adopted by the industry is facing serious challenges in terms of storage time and power consumption while developing to nanometer feature size. [0003] The floating-gate non-vol...

AI Technical Summary

Problems solved by technology

It can be seen that due to the separation and storage characteristics of nanocrystals, the traditional operation method can only inject electrons at the drain end, and most of the electrons are stored at the drain end, which greatly limits the effect of high-efficiency programming and reading methods of nanocrystal memory.

Images