| 摘要 |
PURPOSE: A method for fabricating a semiconductor flash memory cell is provided to improve capacity and yield by basically preventing a residual ONO layer from being formed on a sidewall such that the ONO layer can function as a fatal defect of a subsequent process in removing the ONO layer and polysilicon for forming a logic region. CONSTITUTION: A tunneling oxide layer(2) is deposited on a silicon substrate(1). Polysilicon(3) for a floating gate is formed in a flash cell region, the polysilicon in the logic region is eliminated. After a buffer oxide layer is deposited on the polysilicon, an ion implantation process is performed. The buffer oxide layer is eliminated. After a tunneling ONO layer(4) is deposited in the flash cell region, a patterning process is performed to eliminate the ONO layer in the logic region. After a tunneling oxide layer(6) is deposited in the logic region, polysilicon(7) for a control gate and a logic gate is deposited. The polysilicon for the control gate and the logic gate is patterned and etched.
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