| 摘要 |
<p>A semiconductor memory device and a method for manufacturing the same are provided to improve a threshold voltage of a semiconductor memory device by surrounding the surface of a floating gate with a nano-grain film. A tunnel insulation layer(101), a first nano grain layer(102), a floating gate conductive film(103), a second nano grain film(104), and a hard mask film are successively formed on a semiconductor substrate(100). After the hard mask film selectively is etched, the second nano grain film, the floating gate conductive film, the first nano grain film, the turner insulating layer, and the semiconductor substrate are successively etched through the etching process so that an element isolating trench(106) is formed. The insulating layer is formed on the whole surface of substrate and the element isolating trench is filled up. The planarization process of the substrate is performed so that a hard mask film is exposed, so forming the element isolation film(107).</p> |
