摘要 |
A method of fabricating a non-volatile flash memory device, wherein a gate structure is formed on a substrate. The method includes at least the following steps. The substrate is implanted with first ions to form a source region in the substrate. A tunneling oxide layer is formed on the substrate. A silicon nitride layer is formed on the substrate. The silicon nitride is etched back to form a silicon nitride spacer on the sides of the gate structure. The substrate is implanted with second ions to form a drain region in the substrate. An oxide layer is formed over the substrate and the gate structure. Then, a polysilicon layer is formed on the oxide layer. The gate structure is used as a selection gate, the silicon nitride spacer is used to store electrons, and the polysilicon layer is used as a controlling gate. The flash memory device can free memory cells by from the influences of over-erased effect.
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