| 摘要 |
<p>A method for manufacturing a flash memory device is provided to improve the cycling characteristic and device reliability by using an HDP(High Density Plasma) oxide layer as an isolation layer and to improve a program operation speed by maximizing the contact area of a dielectric film using a cleaning process capable of recessing an exposed portion of the isolation layer between floating gates. A substrate(30) having a first polysilicon layer(32) is provided, wherein the first polysilicon layer is electrically isolated by an isolation layer(37). Both sidewalls of the first polysilicon layer are exposed to the outside by recessing selectively the isolation layer. A second polysilicon layer(38) is formed on the exposed portion of the first polysilicon layer. The isolation layer is recessed again from a portion between second polysilicon layers. A dielectric film(41) is formed along an upper surface of the resultant structure. A control gate(42) is formed on the dielectric film. The isolation layer is made of an HDP oxide layer.</p> |
