| 摘要 |
<p>A nonvolatile semiconductor memory device is provided to write data at low voltage and with high efficiency by improving charge retention characteristics in a charge accumulation layer and reducing a thickness of a first insulating layer. A nonvolatile semiconductor memory device includes a semiconductor layer(14), a first insulating layer(18), a charge accumulating layer(20), a second insulating layer(22), and a control gate. A semiconductor layer(14) is formed on a substrate(10) having an insulating surface. An insulating layer(12) that functions as a base film is formed between the substrate(10) and the semiconductor layer(14). The insulating layer(12) is used to prevent diffusion and contamination by an impurity such as an alkali metal into the semiconductor layer(14) from the substrate(10), and the insulating layer(12) is formed as a blocking layer. The insulating layer(12) is made of an insulating material such as silicon oxide, silicon nitride, silicon containing oxygen and nitrogen by using a CVD method and a sputtering method.</p> |
