| 摘要 |
<p>A method for manufacturing a flash memory device is provided to prevent a current leakage and reduce EOT(Electric Oxide Thickness) by preventing impurity of the following floating gate from being diffused to a tunnel insulating layer by forming an ion implantation layer. A tunnel insulating layer(101) is formed on a semiconductor substrate(100). An ion implantation layer(102) is formed in an upper part of the tunnel insulating layer by performing a plasma nitrification process. A first conductive layer(103) for the floating gate having the grain of the cylinder structure is formed on the overall structure including the ion implantation layer. A second conductive layer(104) for the floating gate is formed on the overall structure including a first polysilicon layer. The dielectric film(107) and a control gate conductive layer(108) are formed on the overall structure including the second conductive layer for the floating gate. The plasma nitrification process is performed between 350 and 500 degrees centigrade. A ration of Ar gas and N2 gas is 1:1 to 3:1 in the plasma nitrification process.</p> |
